This document presents a comparative study of different sensorless speed estimation methods for permanent magnet synchronous motor (PMSM) drives. It discusses several categories of estimation methods, including fundamental excitation methods (both non-adaptive and adaptive), saliency and signal injection methods, and artificial intelligence methods. Fundamental excitation methods that use monitored voltages and currents or estimate flux are described. The document also highlights challenges with sensorless control at low speeds, such as errors from data acquisition, voltage distortion, and parameter variations. Overall, the document provides an overview of common sensorless speed estimation techniques for PMSMs and compares their advantages and disadvantages.
The document proposes a direct torque control (DTC) method for induction motors that combines space vector modulation (SVM) and an adaptive stator flux observer. It aims to preserve the fast dynamic response of DTC while improving steady-state performance and reducing torque ripple through SVM. An adaptive flux observer is designed using state feedback control theory to ensure stability and robustness. Simulation results validate the effectiveness of the proposed DTC-SVM approach with PI control and an adaptive flux observer in reducing torque ripple compared to conventional DTC.
This document summarizes a paper that models and simulates a switched reluctance motor (SRM) to minimize torque ripple through different converter topologies and control strategies. The paper develops a mathematical model of a 6/4 SRM in Matlab/Simulink. It simulates the motor with asymmetric, Miller, and modified Miller converters. Torque ripple is evaluated using power spectrum density analysis. The modified Miller converter shows better performance in minimizing torque ripple compared to the other topologies. The document concludes the modified Miller converter combined with closed-loop control can effectively reduce torque ripple in SRM for high-speed applications.
Comparison Between Two Different Speed Controls Of The Permanent Magnets Sync...Attou
This paper presents a comparison between two control strategies, field oriented control (FOC) and sliding mode control (SMC). The first study has been done on controlling the
Permanent Magnets Synchronous Machine (PMSM) by using field oriented control technique using a speed sensor to detect the rotor position of the motor. After we present the theory of sliding mode control .We can see from the simulation results that the second proposed control system (SMC), is a robust nonlinear
time optimal controller, that's will be more explained in the appendix.
A novel sliding-mode control of induction motor using space vector modulation...ISA Interchange
This document presents a novel sliding-mode control method for torque control of induction motors that integrates sliding-mode control and space vector modulation. The sliding-mode control provides robustness while the space vector modulation improves torque, flux and current performance by reducing ripple. Simulation results show the proposed control scheme provides robust dynamic characteristics with low torque ripple.
This document discusses techniques for mitigating conducted electromagnetic interference (EMI) in DC-DC converter topologies. It analyzes three random pulse width modulation techniques - Randomized Trailing Edge with Randomized Pulse Width Modulation, Randomized Trailing Edge with Randomized Pulse Position Modulation, and Constant Trailing Edge with Randomized Duty Ratio and Randomized Pulse Position Modulation with Fixed Carrier Frequency. Analytical derivations of the power spectral density are presented for each technique. The techniques aim to spread harmonic power in the frequency domain and reduce electromagnetic interference without using additional hardware components.
This document summarizes a research paper that proposes a Model Reference Adaptive Controller (MRAC) for online estimation of rotor time constant and speed for indirect field oriented control of an induction motor drive. The MRAC design is based on reactive power concepts and consists of a reference model that is independent of slip speed and an adjustable model that depends on slip speed. The difference between the instantaneous reactive power computed by the reference model and the steady-state reactive power computed by the adjustable model is used as an error signal for an adaptation mechanism to estimate the slip speed and rotor resistance. Simulation results show the proposed MRAC approach can accurately estimate rotor time constant and speed.
Direct Flux Vector Control of Induction Motor Drives with Maximum Efficiency ...IRJET Journal
This document proposes a direct flux vector control strategy for induction motor drives to maximize efficiency at a given torque demand. It involves computing an optimal "maximum efficiency per torque" stator flux map offline using no-load and short-circuit test data. During operation, the control system regulates the stator flux according to the desired torque level using the optimal flux reference from the precomputed map. This strategy significantly improves efficiency below rated torque compared to constant rated flux operation. The document also describes modeling the induction motor losses, including iron losses based on stator flux and frequency, to calibrate the machine loss model used for efficiency optimization.
This paper investigates a novel dual-rotor permanent magnet synchronous motor (DRPMSM) through modeling and simulation. The model of the DRPMSM is constructed in MATLAB/Simulink. Vector control and space vector PWM control strategies are used to simulate the motor model. The simulation results show the model operates correctly under both control strategies. The responses of torque, speed and current are analyzed and compared under the different control strategies. Key characteristics of the DRPMSM such as the relationship between the speeds of the inner and outer rotors are also analyzed.
The document proposes a direct torque control (DTC) method for induction motors that combines space vector modulation (SVM) and an adaptive stator flux observer. It aims to preserve the fast dynamic response of DTC while improving steady-state performance and reducing torque ripple through SVM. An adaptive flux observer is designed using state feedback control theory to ensure stability and robustness. Simulation results validate the effectiveness of the proposed DTC-SVM approach with PI control and an adaptive flux observer in reducing torque ripple compared to conventional DTC.
This document summarizes a paper that models and simulates a switched reluctance motor (SRM) to minimize torque ripple through different converter topologies and control strategies. The paper develops a mathematical model of a 6/4 SRM in Matlab/Simulink. It simulates the motor with asymmetric, Miller, and modified Miller converters. Torque ripple is evaluated using power spectrum density analysis. The modified Miller converter shows better performance in minimizing torque ripple compared to the other topologies. The document concludes the modified Miller converter combined with closed-loop control can effectively reduce torque ripple in SRM for high-speed applications.
Comparison Between Two Different Speed Controls Of The Permanent Magnets Sync...Attou
This paper presents a comparison between two control strategies, field oriented control (FOC) and sliding mode control (SMC). The first study has been done on controlling the
Permanent Magnets Synchronous Machine (PMSM) by using field oriented control technique using a speed sensor to detect the rotor position of the motor. After we present the theory of sliding mode control .We can see from the simulation results that the second proposed control system (SMC), is a robust nonlinear
time optimal controller, that's will be more explained in the appendix.
A novel sliding-mode control of induction motor using space vector modulation...ISA Interchange
This document presents a novel sliding-mode control method for torque control of induction motors that integrates sliding-mode control and space vector modulation. The sliding-mode control provides robustness while the space vector modulation improves torque, flux and current performance by reducing ripple. Simulation results show the proposed control scheme provides robust dynamic characteristics with low torque ripple.
This document discusses techniques for mitigating conducted electromagnetic interference (EMI) in DC-DC converter topologies. It analyzes three random pulse width modulation techniques - Randomized Trailing Edge with Randomized Pulse Width Modulation, Randomized Trailing Edge with Randomized Pulse Position Modulation, and Constant Trailing Edge with Randomized Duty Ratio and Randomized Pulse Position Modulation with Fixed Carrier Frequency. Analytical derivations of the power spectral density are presented for each technique. The techniques aim to spread harmonic power in the frequency domain and reduce electromagnetic interference without using additional hardware components.
This document summarizes a research paper that proposes a Model Reference Adaptive Controller (MRAC) for online estimation of rotor time constant and speed for indirect field oriented control of an induction motor drive. The MRAC design is based on reactive power concepts and consists of a reference model that is independent of slip speed and an adjustable model that depends on slip speed. The difference between the instantaneous reactive power computed by the reference model and the steady-state reactive power computed by the adjustable model is used as an error signal for an adaptation mechanism to estimate the slip speed and rotor resistance. Simulation results show the proposed MRAC approach can accurately estimate rotor time constant and speed.
Direct Flux Vector Control of Induction Motor Drives with Maximum Efficiency ...IRJET Journal
This document proposes a direct flux vector control strategy for induction motor drives to maximize efficiency at a given torque demand. It involves computing an optimal "maximum efficiency per torque" stator flux map offline using no-load and short-circuit test data. During operation, the control system regulates the stator flux according to the desired torque level using the optimal flux reference from the precomputed map. This strategy significantly improves efficiency below rated torque compared to constant rated flux operation. The document also describes modeling the induction motor losses, including iron losses based on stator flux and frequency, to calibrate the machine loss model used for efficiency optimization.
This paper investigates a novel dual-rotor permanent magnet synchronous motor (DRPMSM) through modeling and simulation. The model of the DRPMSM is constructed in MATLAB/Simulink. Vector control and space vector PWM control strategies are used to simulate the motor model. The simulation results show the model operates correctly under both control strategies. The responses of torque, speed and current are analyzed and compared under the different control strategies. Key characteristics of the DRPMSM such as the relationship between the speeds of the inner and outer rotors are also analyzed.
MODELLING AND IMPLEMENTATION OF AN IMPROVED DSVM SCHEME FOR PMSM DTCpaperpublications3
This document discusses modelling and implementing an improved direct self control (DSC) scheme for permanent magnet synchronous motors (PMSMs) using discrete space vector modulation (DSVM). It begins with an overview of field oriented control and direct torque control techniques for PMSMs. It then presents the PMSM model and basic direct torque control scheme. Issues with the basic DTC scheme like torque and flux ripples are discussed. The document reviews the existing DSVM DTC technique and proposes a new DSVM DTC scheme for PMSMs that takes motor speed and torque/flux errors into account. Comparisons of performance and switching losses between basic DTC and improved DSVM DTC are made through simulation and experiments.
DSP-Based Sensorless Speed Control of a Permanent Magnet Synchronous Motor us...IJPEDS-IAES
This document summarizes an experiment on sensorless speed control of a permanent magnet synchronous motor (PMSM) using a sliding mode current observer (SMCO). A SMCO was implemented to estimate the rotor position based on estimated back electromotive forces. The rotor speed was then calculated by differentiating the estimated rotor position. The control system was developed on a Texas Instruments TMS320LF2812 digital signal processor and tested on a Pittman 3441 series PMSM. Experimental results validated the real-time implementation and showed the effectiveness of the sensorless speed control approach using an SMCO.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document provides a review of different position estimation methods for permanent magnet synchronous motors (PMSMs). It discusses indirect methods based on back electromotive force (EMF) detection, model-based methods using flux linkage or inductance estimation, and saliency-based methods using high frequency signal injection. Model-based observer approaches like extended Kalman filters are highlighted as effective for medium- and high-speed operation due to good disturbance rejection and robustness. The review evaluates the performance and limitations of different position estimation techniques for sensorless control of PMSMs.
A NEW FUZZY LOGIC BASED SPACE VECTOR MODULATION APPROACH ON DIRECT TORQUE CON...csandit
The induction motors are indispensable motor types for industrial applications due to its wellknown
advantages. Therefore, many kind of control scheme are proposed for induction motors
over the past years and direct torque control has gained great importance inside of them due to
fast dynamic torque response behavior and simple control structure. This paper suggests a new
approach on the direct torque controlled induction motors, Fuzzy logic based space vector
modulation, to overcome disadvantages of conventional direct torque control like high torque
ripple. In the proposed approach, optimum switching states are calculated by fuzzy logic
controller and applied by space vector pulse width modulator to voltage source inverter. In
order to test and compare the proposed DTC scheme with conventional DTC scheme
simulations, in Matlab/Simulink, have been carried out in different speed and load conditions.
The simulation results showed that a significant improvement in the dynamic torque and speed
responses when compared to the conventional DTC scheme.
Novelty Method of Speed Control Analysis of Permanent Magnet Brushless DC MotorIRJET Journal
This document summarizes a study on speed control of permanent magnet brushless DC motors (PMBLDC). It begins with an introduction to PMBLDC motors and their closed-loop speed control system using a PI controller. It then presents the mathematical model developed to simulate the motor drive system in LabVIEW. Key aspects of the model include the motor equations, torque equation, voltage and current relationships, and mechanical model relating speed, position, load torque and friction. Simulation results are used to analyze the motor's dynamic response and tune the PI controller gains.
Numerous studies had been made to improve the switched reluctance motor operation depend on the modification of the machine design, proposing the converter designs and/or applying a suitable control method. This paper introduces the field orientation control method for that motor using a simple and very efficient DC-DC converter topology. This control method is presented by two techniques; first technique is the advance of the turn-on switching angle and the other technique is the retard/delay of the turn-off switching angle. Instantaneous and average motor characteristics are obtained using Matlab/Simulink software package. Comparison between the simulation results presented using two converter types. A precise speed and torque control are obtained. The average total torque per current is maximized.
Adaption of motor paramenters in sensorless pmsm driverwarluck88
The document proposes an online method for estimating the stator resistance and permanent magnet flux in sensorless permanent magnet synchronous motor drives. An adaptive observer augmented with high-frequency signal injection is used. Excess information in the observer is used to adapt the motor parameters. At low speeds, stator resistance is estimated from a speed correction term. At medium and high speeds, permanent magnet flux is estimated from d-axis current estimation error. Steady-state and small-signal analyses investigate parameter estimation sensitivity. Adaptation laws are designed for parameter convergence shown via simulation and experiment. Stator resistance adaptation works down to zero speed in sensorless control.
Comparison of Different Rules Based Fuzzy Logic Controller for PMSM DrivesIOSR Journals
This document compares the performance of three different rule-based fuzzy logic controllers (FLCs) with 49, 25, and 9 rules for controlling the speed of a permanent magnet synchronous motor (PMSM) drive system. Simulation results show that a FLC with more rules (49 rules) provides superior performance in terms of speed tracking accuracy and settling time compared to FLCs with fewer rules (25 and 9 rules), but requires more computational resources. The performance decreases as the number of rules in the FLC decreases. Thus, there is a tradeoff between control performance and computational complexity depending on the number of rules used in the FLC for PMSM speed control applications.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document presents a comparison of two sliding mode observers for sensorless speed and position estimation of a permanent magnet synchronous motor (PMSM). The first observer uses a sigmoidal function, while the proposed observer uses a tan hyperbolic function. Simulation results show that the observer with the tan hyperbolic function produces smoother estimation of rotor speed and back electromotive force, with lower peak values compared to the sigmoidal observer. This reduces chattering and improves the accuracy of rotor position and speed estimation, demonstrating the effectiveness of the tan hyperbolic function for sliding mode observer applications.
This paper proposes a sensorless sliding mode control (SMC) for a five phase permanent magnet synchronous motor (PMSM) based on a sliding mode observer (SMO). The stability of the proposed strategy is proved in the sense of the Lyapunov theory. The sliding mode controller is designed with an integral switching surface and the sliding mode observer is developed for the estimation of rotor position and rotor speed. The proposed sensorless control strategy exhibits good dynamic response to disturbances. Simulation results are provided to prove the effectiveness of the proposed strategy.
3.[14 28]space vector based dual zero-vector random centered distribution pwm...Alexander Decker
This document presents a novel dual zero-vector random centered distribution PWM (DZRCDPWM) algorithm for direct torque controlled induction motor drive to reduce acoustic noise. The proposed algorithm uses two zero voltage vectors (V0 and V7) and selects one randomly based on the operating modulation index. Simulation results show the DZRCDPWM algorithm reduces acoustic noise harmonics compared to the conventional SVPWM algorithm by distributing the pulse patterns randomly. The DZRCDPWM provides better performance over the entire modulation index range for induction motor drive control with reduced acoustic noise.
11.space vector based dual zero vector random centered distribution pwm algor...Alexander Decker
This document presents a novel dual zero-vector random centered distribution PWM (DZRCDPWM) algorithm for direct torque controlled induction motor drive to reduce acoustic noise. The proposed algorithm uses two zero voltage vectors (V0 and V7) and selects one randomly based on the operating modulation index. Simulation results show the DZRCDPWM algorithm reduces acoustic noise harmonics compared to the conventional SVPWM algorithm by distributing the pulse patterns randomly. The DZRCDPWM provides better performance over the entire modulation index range for induction motor drive control with reduced acoustic noise.
An Implementation Mechanisms of SVM Control Strategies Applied to Five Levels...IJPEDS-IAES
In the area of the energy control with high voltage and power, the multilevel inverters constitute a relatively recent research orientation. The current applications of this technology are in the domains of the high voltage (over hundred kV), variable speed drives, transport and distribution of a good quality of electrical energy (HVDC, FACTS system, ....). To improve the output voltage for such inverters, many different modulation strategies have been developed. Among these strategies, the SVM (Space Vector Modulation). The technique provide the nearest switching vectors sequence to the reference vector without involving trigonometric functions and provide the additional advantages of superior harmonic quality. In this paper, we analyze different mechanisms of the output voltage synthesis and the problem of even order harmonic production. With the proposed a new trajectory SVM, which can eliminate all the even order harmonics for five levels inverter. Show clearly how to deduce the trajectories from the sequences allowing to have better performances among several possible trajectories. It is dedicated to the application of two particular trajectories.
TORQUE RIPPLE MINIMIZATION OF MATRIX CONVERTER-FED PMSM DRIVES USING ADVANCED...ijscmcj
An advanced direct torque control (DTC) technique using Model predictive control (MPC) is proposed for matrix converter (MC)-based permanent-magnet synchronous motor (PMSM) drive system, which reduces the torque ripples, does not need the duty cycle calculation, and ensures the fixed switching frequency. Analytical expressions of change rates of torque and flux of PMSM as a function of MC - dqo components are derived. The predictive model of PMSM and MC is realized by means of State model. Then, the advanced MC-fed DTC algorithm is implemented based on Cost function evaluation. The simulation results exhibit remarkable torque ripple reduction with the help of MPC. As a result, the proposed strategy is proved to be effective in minimizing the torque ripples for MC-based PMSM drives.
Position sensorless vector control of pmsm for electrical household applicanceswarluck88
This document proposes a position sensorless vector control method for permanent magnet synchronous motors (PMSMs) suitable for electrical household appliance motor drives. It presents a simple position estimation equation and describes its derivation. It also proposes a simplified vector control method that does not require an automatic speed or current regulator but can achieve similar drive performance to conventional vector control under steady state conditions. Simulation and experimental results on a battery-driven cordless vacuum cleaner motor demonstrate the effectiveness of the proposed high-speed sensorless drive system using a typical low-cost microcontroller.
This document reviews sliding mode observers for sensorless control of permanent magnet synchronous motor drives. It begins with an introduction to permanent magnet synchronous motors and their advantages over other motor types. It then discusses speed estimation schemes for sensorless PMSM drives, including adaptive methods using observers like Luenberger observers and sliding mode observers. The document focuses on sliding mode observers, explaining conventional sliding mode observers, observers using a sigmoid function instead of a signum function to reduce chattering, and terminal sliding mode observers. Sliding mode observers are widely used for sensorless control due to their robustness to parameter variations and simplicity.
This document summarizes a research paper on sensorless speed control of a permanent magnet synchronous motor (PMSM) using direct torque control (DTC) with a model reference adaptive system (MRAS). It first describes the structure and equations of a PMSM and provides an overview of DTC. It then introduces MRAS for sensorless speed estimation. Simulation results using MATLAB show that the proposed DTC method with MRAS provides precise estimated speed, fast torque response, and good dynamic performance under sudden load changes.
Speed and Torque Control Challenge of PMSMIJMTST Journal
This paper presents modeling and implementation Challenge of speed toqrue rotor field oriented control of
permanent magnet synchronous machine (PMSM)drive. An experimental setup consisting of IGBT inverters
and a -TMS320LF240 DSP based digital controller is developed in the laboratory in IIT Kharagpur to
implement the control algorithms. A voltage model based flux observer is used for estimating the speed and
position of PMSM. In order to get good starting characteristics a rotor initial position algorithm is also
implemented in the control algorithm. For control purpose PMSM is consider like dc motor. The torque and
speed in the dc motor can be controlled independently by controlling armature current and field current
respectively ensures that dc motor has good dynamic performance.
MODELLING AND IMPLEMENTATION OF AN IMPROVED DSVM SCHEME FOR PMSM DTCpaperpublications3
This document discusses modelling and implementing an improved direct self control (DSC) scheme for permanent magnet synchronous motors (PMSMs) using discrete space vector modulation (DSVM). It begins with an overview of field oriented control and direct torque control techniques for PMSMs. It then presents the PMSM model and basic direct torque control scheme. Issues with the basic DTC scheme like torque and flux ripples are discussed. The document reviews the existing DSVM DTC technique and proposes a new DSVM DTC scheme for PMSMs that takes motor speed and torque/flux errors into account. Comparisons of performance and switching losses between basic DTC and improved DSVM DTC are made through simulation and experiments.
DSP-Based Sensorless Speed Control of a Permanent Magnet Synchronous Motor us...IJPEDS-IAES
This document summarizes an experiment on sensorless speed control of a permanent magnet synchronous motor (PMSM) using a sliding mode current observer (SMCO). A SMCO was implemented to estimate the rotor position based on estimated back electromotive forces. The rotor speed was then calculated by differentiating the estimated rotor position. The control system was developed on a Texas Instruments TMS320LF2812 digital signal processor and tested on a Pittman 3441 series PMSM. Experimental results validated the real-time implementation and showed the effectiveness of the sensorless speed control approach using an SMCO.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document provides a review of different position estimation methods for permanent magnet synchronous motors (PMSMs). It discusses indirect methods based on back electromotive force (EMF) detection, model-based methods using flux linkage or inductance estimation, and saliency-based methods using high frequency signal injection. Model-based observer approaches like extended Kalman filters are highlighted as effective for medium- and high-speed operation due to good disturbance rejection and robustness. The review evaluates the performance and limitations of different position estimation techniques for sensorless control of PMSMs.
A NEW FUZZY LOGIC BASED SPACE VECTOR MODULATION APPROACH ON DIRECT TORQUE CON...csandit
The induction motors are indispensable motor types for industrial applications due to its wellknown
advantages. Therefore, many kind of control scheme are proposed for induction motors
over the past years and direct torque control has gained great importance inside of them due to
fast dynamic torque response behavior and simple control structure. This paper suggests a new
approach on the direct torque controlled induction motors, Fuzzy logic based space vector
modulation, to overcome disadvantages of conventional direct torque control like high torque
ripple. In the proposed approach, optimum switching states are calculated by fuzzy logic
controller and applied by space vector pulse width modulator to voltage source inverter. In
order to test and compare the proposed DTC scheme with conventional DTC scheme
simulations, in Matlab/Simulink, have been carried out in different speed and load conditions.
The simulation results showed that a significant improvement in the dynamic torque and speed
responses when compared to the conventional DTC scheme.
Novelty Method of Speed Control Analysis of Permanent Magnet Brushless DC MotorIRJET Journal
This document summarizes a study on speed control of permanent magnet brushless DC motors (PMBLDC). It begins with an introduction to PMBLDC motors and their closed-loop speed control system using a PI controller. It then presents the mathematical model developed to simulate the motor drive system in LabVIEW. Key aspects of the model include the motor equations, torque equation, voltage and current relationships, and mechanical model relating speed, position, load torque and friction. Simulation results are used to analyze the motor's dynamic response and tune the PI controller gains.
Numerous studies had been made to improve the switched reluctance motor operation depend on the modification of the machine design, proposing the converter designs and/or applying a suitable control method. This paper introduces the field orientation control method for that motor using a simple and very efficient DC-DC converter topology. This control method is presented by two techniques; first technique is the advance of the turn-on switching angle and the other technique is the retard/delay of the turn-off switching angle. Instantaneous and average motor characteristics are obtained using Matlab/Simulink software package. Comparison between the simulation results presented using two converter types. A precise speed and torque control are obtained. The average total torque per current is maximized.
Adaption of motor paramenters in sensorless pmsm driverwarluck88
The document proposes an online method for estimating the stator resistance and permanent magnet flux in sensorless permanent magnet synchronous motor drives. An adaptive observer augmented with high-frequency signal injection is used. Excess information in the observer is used to adapt the motor parameters. At low speeds, stator resistance is estimated from a speed correction term. At medium and high speeds, permanent magnet flux is estimated from d-axis current estimation error. Steady-state and small-signal analyses investigate parameter estimation sensitivity. Adaptation laws are designed for parameter convergence shown via simulation and experiment. Stator resistance adaptation works down to zero speed in sensorless control.
Comparison of Different Rules Based Fuzzy Logic Controller for PMSM DrivesIOSR Journals
This document compares the performance of three different rule-based fuzzy logic controllers (FLCs) with 49, 25, and 9 rules for controlling the speed of a permanent magnet synchronous motor (PMSM) drive system. Simulation results show that a FLC with more rules (49 rules) provides superior performance in terms of speed tracking accuracy and settling time compared to FLCs with fewer rules (25 and 9 rules), but requires more computational resources. The performance decreases as the number of rules in the FLC decreases. Thus, there is a tradeoff between control performance and computational complexity depending on the number of rules used in the FLC for PMSM speed control applications.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document presents a comparison of two sliding mode observers for sensorless speed and position estimation of a permanent magnet synchronous motor (PMSM). The first observer uses a sigmoidal function, while the proposed observer uses a tan hyperbolic function. Simulation results show that the observer with the tan hyperbolic function produces smoother estimation of rotor speed and back electromotive force, with lower peak values compared to the sigmoidal observer. This reduces chattering and improves the accuracy of rotor position and speed estimation, demonstrating the effectiveness of the tan hyperbolic function for sliding mode observer applications.
This paper proposes a sensorless sliding mode control (SMC) for a five phase permanent magnet synchronous motor (PMSM) based on a sliding mode observer (SMO). The stability of the proposed strategy is proved in the sense of the Lyapunov theory. The sliding mode controller is designed with an integral switching surface and the sliding mode observer is developed for the estimation of rotor position and rotor speed. The proposed sensorless control strategy exhibits good dynamic response to disturbances. Simulation results are provided to prove the effectiveness of the proposed strategy.
3.[14 28]space vector based dual zero-vector random centered distribution pwm...Alexander Decker
This document presents a novel dual zero-vector random centered distribution PWM (DZRCDPWM) algorithm for direct torque controlled induction motor drive to reduce acoustic noise. The proposed algorithm uses two zero voltage vectors (V0 and V7) and selects one randomly based on the operating modulation index. Simulation results show the DZRCDPWM algorithm reduces acoustic noise harmonics compared to the conventional SVPWM algorithm by distributing the pulse patterns randomly. The DZRCDPWM provides better performance over the entire modulation index range for induction motor drive control with reduced acoustic noise.
11.space vector based dual zero vector random centered distribution pwm algor...Alexander Decker
This document presents a novel dual zero-vector random centered distribution PWM (DZRCDPWM) algorithm for direct torque controlled induction motor drive to reduce acoustic noise. The proposed algorithm uses two zero voltage vectors (V0 and V7) and selects one randomly based on the operating modulation index. Simulation results show the DZRCDPWM algorithm reduces acoustic noise harmonics compared to the conventional SVPWM algorithm by distributing the pulse patterns randomly. The DZRCDPWM provides better performance over the entire modulation index range for induction motor drive control with reduced acoustic noise.
An Implementation Mechanisms of SVM Control Strategies Applied to Five Levels...IJPEDS-IAES
In the area of the energy control with high voltage and power, the multilevel inverters constitute a relatively recent research orientation. The current applications of this technology are in the domains of the high voltage (over hundred kV), variable speed drives, transport and distribution of a good quality of electrical energy (HVDC, FACTS system, ....). To improve the output voltage for such inverters, many different modulation strategies have been developed. Among these strategies, the SVM (Space Vector Modulation). The technique provide the nearest switching vectors sequence to the reference vector without involving trigonometric functions and provide the additional advantages of superior harmonic quality. In this paper, we analyze different mechanisms of the output voltage synthesis and the problem of even order harmonic production. With the proposed a new trajectory SVM, which can eliminate all the even order harmonics for five levels inverter. Show clearly how to deduce the trajectories from the sequences allowing to have better performances among several possible trajectories. It is dedicated to the application of two particular trajectories.
TORQUE RIPPLE MINIMIZATION OF MATRIX CONVERTER-FED PMSM DRIVES USING ADVANCED...ijscmcj
An advanced direct torque control (DTC) technique using Model predictive control (MPC) is proposed for matrix converter (MC)-based permanent-magnet synchronous motor (PMSM) drive system, which reduces the torque ripples, does not need the duty cycle calculation, and ensures the fixed switching frequency. Analytical expressions of change rates of torque and flux of PMSM as a function of MC - dqo components are derived. The predictive model of PMSM and MC is realized by means of State model. Then, the advanced MC-fed DTC algorithm is implemented based on Cost function evaluation. The simulation results exhibit remarkable torque ripple reduction with the help of MPC. As a result, the proposed strategy is proved to be effective in minimizing the torque ripples for MC-based PMSM drives.
Position sensorless vector control of pmsm for electrical household applicanceswarluck88
This document proposes a position sensorless vector control method for permanent magnet synchronous motors (PMSMs) suitable for electrical household appliance motor drives. It presents a simple position estimation equation and describes its derivation. It also proposes a simplified vector control method that does not require an automatic speed or current regulator but can achieve similar drive performance to conventional vector control under steady state conditions. Simulation and experimental results on a battery-driven cordless vacuum cleaner motor demonstrate the effectiveness of the proposed high-speed sensorless drive system using a typical low-cost microcontroller.
This document reviews sliding mode observers for sensorless control of permanent magnet synchronous motor drives. It begins with an introduction to permanent magnet synchronous motors and their advantages over other motor types. It then discusses speed estimation schemes for sensorless PMSM drives, including adaptive methods using observers like Luenberger observers and sliding mode observers. The document focuses on sliding mode observers, explaining conventional sliding mode observers, observers using a sigmoid function instead of a signum function to reduce chattering, and terminal sliding mode observers. Sliding mode observers are widely used for sensorless control due to their robustness to parameter variations and simplicity.
This document summarizes a research paper on sensorless speed control of a permanent magnet synchronous motor (PMSM) using direct torque control (DTC) with a model reference adaptive system (MRAS). It first describes the structure and equations of a PMSM and provides an overview of DTC. It then introduces MRAS for sensorless speed estimation. Simulation results using MATLAB show that the proposed DTC method with MRAS provides precise estimated speed, fast torque response, and good dynamic performance under sudden load changes.
Speed and Torque Control Challenge of PMSMIJMTST Journal
This paper presents modeling and implementation Challenge of speed toqrue rotor field oriented control of
permanent magnet synchronous machine (PMSM)drive. An experimental setup consisting of IGBT inverters
and a -TMS320LF240 DSP based digital controller is developed in the laboratory in IIT Kharagpur to
implement the control algorithms. A voltage model based flux observer is used for estimating the speed and
position of PMSM. In order to get good starting characteristics a rotor initial position algorithm is also
implemented in the control algorithm. For control purpose PMSM is consider like dc motor. The torque and
speed in the dc motor can be controlled independently by controlling armature current and field current
respectively ensures that dc motor has good dynamic performance.
A New QEA Based High Performance Sensorless Control of IM DriveIDES Editor
Quantum Evolutionary Algorithm (QEA) based
proportional-integral (PI) controller tuning is used for getting
fast speed response induction motor (IM) drive. A high
performance simple sensorless control of induction motor
drive is also presented in this paper. The control principle is
based on direct torque control (DTC) with space vector
modulation (SVM) technique. The SVM reduces the torque
and flux ripples and improve steady state performance. A
correlated real time recurrent learning (CRTRL) algorithm
based on recurrent neural network (RNN) is used to estimate
rotor flux which eliminates rotor position sensor. A simple
speed estimator for the induction motor is proposed to make
the controller cost effective and speed sensorless. The proposed
control methodologies and simulation results are given and
discussed.
Simulation and Analysis of Modified DTC of PMSMIJECEIAES
This research paper describes the simulation and analysis of the modified DTC for Surface mounted Permanent Magnet Synchronous Motor (SPMSM) using PI controller. Among all of the various drive systems,PMSM is widely used for accurate speed and torque control, with greater efficiency, superior torque to inertia and high power density.The Conventional DTC secheme widely used for this purpose but it is failed to achieve desirable performance of the system for which the modified DTC secheme is propsed.The modified DTC algorithm controls the voltage vectors, directly from a simple look up table depending on outcome of the torque and indirectly flux controllers.The overall drive system can be implemented in SIMULINK/MATLAB environment.The modified DTC is validated with loading conditions.The simulated results are focused on the speed, settling time at loaded conditions, torque and flux linkages ripple and THD in the phase current for modified DTC applied to SPMSM.
Vector Controlled Two Phase Induction Motor and To A Three Phase Induction MotorIJERA Editor
This paper presents vector controlled of single phase induction motor. some problems are with vector controlled SPIM.As SPIM’s are typically to maintain speed and also about the complex implementation of vector controlled SPIM.the implemantion of the proposed vector controlled TPIM compared to the vector controlled SPIM. The general modal sutable for vector control of the unsymmentrical two phase induction motor and also stator flux oriented controlled strategies are analized. the comparative performance of both has been presented in this work with help of a practical three phase motor.
The document describes two improved direct torque control (DTC) methods for a three-level inverter-fed induction motor drive. Method I selects voltage vectors based on torque and flux demands while inserting intermediate vectors to ensure neutral point balance and smooth switching. Method II uses discrete space vector modulation to synthesize vectors, decoupling vector selection from circuit limitations and solving neutral point and switching issues. Both methods were validated through MATLAB simulation and experiments to enhance DTC performance for three-level inverters while considering their unique challenges.
This document presents a novel particle swarm optimization technique to optimize PID controller parameters for controlling the speed of a linear brushless DC motor. The PSO algorithm is used to determine the optimal proportional, integral and derivative gains for the PID controller. Simulation results show that the proposed PSO-PID controller improves the dynamic performance of the motor system by reducing rise time, overshoot, settling time and steady state error.
Modeling & Simulation of PMSM Drives with Fuzzy Logic ControllerIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
This document summarizes a research paper that proposes a simple and low-cost speed and position estimator for sensorless permanent magnet synchronous motor (PMSM) drives using an adaptive controller. The estimator uses a simplified mathematical model based on the direct and quadrature reference currents without requiring a voltage probe. Experimental results using a dSPACE hardware implementation demonstrate that the proposed estimator is able to accurately control the PMSM's speed in both forward and reverse directions, as well as during acceleration, deceleration, and when subjected to load disturbances.
IRJET- Analysis the Speed Manage of BLDC Motor Drive using SensorsIRJET Journal
This document analyzes the speed control of a brushless DC motor (BLDC) using sensors. It begins with an introduction to BLDC motors and their advantages over brushed DC motors. It then presents the mathematical modeling of a BLDC motor, including voltage and flux linkage equations. It describes using Hall-effect sensors to sense the rotor position and control the motor. The document discusses using a PI controller for speed control and the challenges in selecting the PI gains. It concludes by presenting the methodology for mathematically modeling the motor, including the electrical and mechanical system dynamics equations.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Iaetsd estimation of damping torque for small-signalIaetsd Iaetsd
This document discusses using particle swarm optimization (PSO) to accurately estimate the damping torque coefficient for assessing small-signal stability in a single machine infinite bus power system. PSO is applied to optimize the damping torque coefficient to maximize damping ratio and improve stability. Time domain simulations were performed under various loading conditions and PSO provided better damping, reducing peak overshoots compared to estimating the coefficient randomly. The results demonstrate the effectiveness of PSO for stability assessment by optimizing the damping torque coefficient.
Performance Characteristics of Induction Motor with FielIJPEDS-IAES
With development of power electronics and control Theories, the AC motor
control becomes easier. So the AC motors are used instead of the DC motor
in the drive applications. With this development, a several methods of control
are invented. The field oriented control and direct torque control are from the
best methods to control the drive systems. This paper is compared between
the field oriented control and direct torque control to show the advantages
and disadvantages of these methods of controls. This study discussed the
effects of these methods of control on the total harmonic distortion of the
current and torque ripples. This occurs through study the performance
characteristics of the AC motor. The motor used in this study is an induction
motor. This study is simulated through the MATLAB program.
Fuzzy Gain-Scheduling Proportional–Integral Control for Improving the Speed B...IJPEDS-IAES
In this article, we have set up a vector control law of induction machine
where we tried different type of speed controllers. Our control strategy is of
type Field Orientated Control (FOC). In this structure we designed a Fuzzy
Gain-Scheduling Proportional–Integral (Pi) controller to obtain best result
regarding the speed of induction machine. At the beginning we designed a Pi
controller with fixed parameters. We came up to these parameters by
identifying the transfer function of this controller to that of Broïda (second
order transfer function). Then we designed a fuzzy logic (FL) controller.
Based on simulation results, we highlight the performances of each
controller. To improve the speed behaviour of the induction machine, we
have designend a controller called “Fuzzy Gain-Scheduling Proportional–
Integral controller” (FGS-PI controller) which inherited the pros of the
aforementioned controllers. The simulation result of this controller will
strengthen its performances.
Performance Analysis of a DTC and SVM Based Field- Orientation Control Induct...IJPEDS-IAES
This study presents a performance analysis of two most popular control strategies for Induction Motor (IM) drives: direct torque control (DTC) and space vector modulation (SVM) strategies. The performance analysis is done by applying field-orientation control (FOC) technique because of its good dynamic response. The theoretical principle, simulation results are discussed to study the dynamic performances of the drive system for individual control strategies using actual parameters of induction motor. A closed loop PI controller scheme has been used. The main purpose of this study is to minimize ripple in torque response curve and to achieve quick speed response as well as to investigate the condition for optimum performance of induction motor drive. Depending on the simulation results this study also presents a detailed comparison between direct torque control and space vector modulation based field-orientation control method for the induction motor drive.
Speed Control and Parameter Variation of Induction Motor Drives using Fuzzy L...IRJET Journal
This document compares the speed control of an induction motor using auto-disturbance rejection controllers (ADRC) and fuzzy logic controllers. It presents the mathematical models and control schemes for both approaches. Simulation results show that the fuzzy logic controller has better performance characteristics than the ADRC controllers in responding to load disturbances, motor parameter variations, and model uncertainty. The fuzzy logic controller is able to settle to the reference speed faster after a disturbance and has a lower steady state error.
Speed Observer Based Load Angle Control of Induction Motor DriveIDES Editor
The performance of induction motor drives
gets improved in the scalar control mode with various
algorithms with speed /position feedback. In this paper
load angle control of induction motor with speed observer
is presented. This eliminates the physical presence of
speed sensor. The basic control of rotor flux vector with
stator current defines the dynamics of torque control. In
this scheme, estimation of feedback variables is obtained
by using algorithm with minimum number of machine
parameters. The speed obtained is thus used in feedback
loop to improve the machine performance. The proposed
algorithm also has a capability to estimate the active and
reactive power of the machine. This is further
incorporated to improve the operating efficiency of the
machine. The observer developed is tested for various
dynamics condition to verify its operating performance in
MATLAB/SIMULINK.
Recently of the main topic of research is the sensorless vector control of induction motor drive, In this paper presents the predictive model reference adaptive system (PMRAS) rotor speed observer, This observer developed from the classical MRAS rotor flux scheme associated with predictive adaptation mechanism designed from the Finite Control Set Model Predictive Control (FCS–MPC) by using a search optimization algorithm for calculate the rotor position which guarantee a minimum speed tuning error signal at each sampling period. The effectiveness of the proposed observer proved with the simulation results, show high dynamic performance speed and position observed in sensorless vector control process at low and zero speed as well robustness against motor parameter variation with different loading conditions.
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A synthetic review of contraceptive supplies in punjabAlexander Decker
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A synthesis of taylor’s and fayol’s management approaches for managing market...Alexander Decker
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A survey paper on sequence pattern mining with incrementalAlexander Decker
This document summarizes four algorithms for sequential pattern mining: GSP, ISM, FreeSpan, and PrefixSpan. GSP is an Apriori-based algorithm that incorporates time constraints. ISM extends SPADE to incrementally update patterns after database changes. FreeSpan uses frequent items to recursively project databases and grow subsequences. PrefixSpan also uses projection but claims to not require candidate generation. It recursively projects databases based on short prefix patterns. The document concludes by stating the goal was to find an efficient scheme for extracting sequential patterns from transactional datasets.
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1. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 5, 2011
Comparative Study of Sensorless Control Methods of PMSM
Drives
Arafa S. Mohamed, Mohamed S. Zaky, Ashraf S. Zein El Din and Hussain A. Yasin
Electrical Engineering Dept., Faculty of Engineering, Minoufiya University,
Shebin El-Kom (32511), Egypt
E-mail: arafamnsr@yahoo.com
Abstract
Recently, permanent magnet synchronous motors (PMSMs) are increasingly used in high performance
variable speed drives of many industrial applications. This is because the PMSM has many features, like
high efficiency, compactness, high torque to inertia ratio, rapid dynamic response, simple modeling and
control, and maintenance-free operation. In most applications, the presence of such a position sensor
presents several disadvantages, such as reduced reliability, susceptibility to noise, additional cost and
weight and increased complexity of the drive system. For these reasons, the development of alternative
indirect methods for speed and position control becomes an important research topic. Many advantages of
sensorless control such as reduced hardware complexity, low cost, reduced size, cable elimination,
increased noise immunity, increased reliability and decreased maintenance. The key problem in sensorless
vector control of ac drives is the accurate dynamic estimation of the stator flux vector over a wide speed
range using only terminal variables (currents and voltages). The difficulty comprises state estimation at
very low speeds where the fundamental excitation is low and the observer performance tends to be poor.
The reasons are the observer sensitivity to model parameter variations, unmodeled nonlinearities and
disturbances, limited accuracy of acquisition signals, drifts, and dc offsets. Poor speed estimation at low
speed is attributed to data acquisition errors, voltage distortion due the PWM inverter and stator resistance
drop which degrading the performance of sensorless drive. Moreover, the noises of system and
measurements are considered other main problems. This paper presents a comprehensive study of the
different methods of speed and position estimations for sensorless PMSM drives. A deep insight of the
advantages and disadvantages of each method is investigated. Furthermore, the difficulties faced sensorless
PMSM drives at low speeds as well as the reasons are highly demonstrated.
Keywords: permanent magnet, synchronous motor, sensorless control, speed estimation, position
estimation, parameter adaptation.
1. Introduction
Permanent magnet synchronous motor (PMSM) drives are replacing classic dc and induction motors drives
in a variety of industrial applications, such as industrial robots and machine tools [1-3]. Advantages of
PMSMs include high efficiency, compactness, high torque to inertia ratio, rapid dynamic response, and
simple modeling and control [4]. Because of these advantages, PMSMSs are indeed excellent for use in
high-performance servo drives where a fast and accurate torque response is required [5, 6]. Permanent
magnet machines can be divided in two categories which are based on the assembly of the permanent
magnets. The permanent magnets can be mounted on the surface of the rotor (surface permanent magnet
synchronous motor - SPMSM) or inside of the rotor (interior permanent magnet synchronous motor -
IPMSM). These two configurations have an influence on the shape of the back electromotive force (back-
EMF) and on the inductance variation. In general, there are two main techniques for the instantaneous
torque control of high-performance variable speed drives: field oriented control (FOC) and direct torque
control (DTC) [7, 8]. They have been invented respectively in the 70’s and in the 80’s. These control
strategies are different on the operation principle but their objectives are the same. They aim both to control
effectively the motor torque and flux in order to force the motor to accurately track the command trajectory
44
2. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 5, 2011
regardless of the machine and load parameter variation or any extraneous disturbances. The main
advantages of DTC are: the absence of coordinate transformations, the absence of a separate voltage
modulation block and of a voltage decoupling circuit and a reduced number of controllers. However, on the
other hand, this solution requires knowledge of the stator flux, electromagnetic torque, angular speed and
position of the rotor [9]. Both control strategies have been successfully implemented in industrial products.
The main drawback of a PMSM is the position sensor. The use of such direct speed/position sensors
implies additional electronics, extra wiring, extra space, frequent maintenance and careful mounting which
detracts from the inherent robustness and reliability of the drive. For these reasons, the development of
alternative indirect methods becomes an important research topic [10, 11]. PMSM drive research has been
concentrated on the elimination of the mechanical sensors at the motor shaft (encoder, resolver, Hall-effect
sensor, etc.) without deteriorating the dynamic performances of the drive. Many advantages of sensorless
ac drives such as reduced hardware complexity, low cost, reduced size, cable elimination, increased noise
immunity, increased reliability and decreased maintenance. Speed sensorless motor drives are also
preferred in hostile environments, and high speed applications [12, 13].
The main objective of this paper is to present a comparative study of the different speed estimation methods
of sensorless PMSM drives with emphasizing of the advantages and disadvantages of each method.
Furthermore, the problems of sensorless PMSM drives at low speeds are demonstrated.
2. PMSM Model
The PMSM model can be derived by taken the following assumptions into consideration:
The induced EMF is sinusoidal
Eddy currents and hysteresis losses are negligible
There is no cage on the rotor
The voltage and flux equations for a PMSM in the rotor reference (d-q) frame can be expressed as [8]:
d ds
ds R s i ds qs (1)
dt
d
qs R s i qs qs ds (2)
dt
ds Ld i ds r (3)
qs Lq i qs (4)
The torque equation can be described as:
3
Te P [ r i qs (Lq Ld )i ds i qs ] (5)
2
The equation for the motor dynamic can be expressed as:
d r 1
(T e T L F r ) (6)
dt J
where the angular frequency is related to the rotor speed as follows:
d
P r (7)
dt
where P is the number of pole pairs, R s , is the stator winding resistance, is the angular frequency, ds ,
qs , and i ds , i qs are d-q components of the stator winding current and voltage, ds and qs are d-q
components of the stator flux linkage, Ld and Lq are d and q axis inductances, and r is the rotor flux
45
3. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 5, 2011
linkage. F is the friction coefficient relating to the rotor speed; J is the moment of inertia of the rotor; is
the electrical angular position of the rotor; and T e and T L are the electrical and load torques of the
PMSM.
3. Speed Estimation Schemes of Sensorless PMSM Drives
Several speed and position estimation algorithms of PMSM drives have been proposed [14]. These methods
can be classified into three main categories. The first category is based on fundamental excitations methods
which are divided into two main groups; non-adaptive or adaptive methods. The second category is based
on saliency and signal injection methods. The third done is based on artificial intelligence methods. These
methods of speed and position estimation can be demonstrated in Figure 1.
Sensorless Control of PMSM
Fundamental Saliency & signal Artificial intelligence
excitations methods injection methods methods
Adaptive methods
Non-adaptive
methods
Figure 1. Speed estimation schemes of sensorless PMSM drives.
3.1. Fundamental Excitations Methods
3.1.1 Non-adaptive Methods
Non-adaptive methods use measured currents and voltages as well as fundamental machine equations of the
PMSM. The characteristic of this method is easy to be computed, responded quickly and almost no delay.
But it required high accurate Motor parameters, more suitable for Motor parameters online identification
[2].
A. Estimators using monitored stator voltages, or currents
For estimating the rotor angle using measured stator voltages and currents different authors follow
different approaches regarding to the used reference frame. This section shows examples for the
perspective in three axis and γ-δ coordinates.
[15, 16] propose the approach with the three axis model. Firstly transformation from the d-q coordinates to
the α-β coordinates have to be done. The transformation matrix as follows:
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cos sin
T dq (8)
sin cos
The transformation matrix from the α-β coordinates to the three axis model is illustrated in equation:
1
1
2 2
3 3
T 23 (9)
2 2
2 2 2
The final equation for the rotor position angle can be found as:
A
r tan 1 ( ) (10)
B
Where
A bs cs R s (i bs i cs ) Ld p (i bs i cs )
(11)
3r (Lq Ld )i as
B 3( as R s i as Ld pi as )
(12)
r (Lq Ld )(i bs i cs )
The position of rotor can thus be obtained in terms of machine voltages and currents in the stator frame
provided r in equation can be evaluated in terms of voltages and currents.
[17] Proposes a voltage model and current model based control which works in the γ-δ reference frame
with the assumption that Ld Lq L . The required speed r can be calculated as follows:
C
r (13)
D
C ( as R s i as Ls pi as )2
(14)
1
( bs cs R s (i bs i cs ) Ls p (i bs i cs ))2
3
D r (15)
The initial position of the rotor at t=0 can be determined by substitution r =0 in above equation:
E
ro tan 1 ( ) (16)
F
Where:
1
E ( bs cs R s (i bs i cs ) Ld p (i bs i cs )) (17)
3
F as R s i as Ld pi as (18)
The currents are detected by a current sensor and the voltages are obtained by calculation which using
information on PWM pattern, dc voltage and dead time.
The calculation is direct and easy with a very quick dynamic response, and no complicated observer is
needed. However, the stator current deviation used in above equations will introduce calculation error due
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to measurement noise. And any uncertainty of motor parameters will cause trouble to the motor position
estimation, which is the biggest problem of this method [18, 19].
B. Flux based position estimators
In this method, the flux linkage is estimated from measured voltages and currents and then the position is
predicted by use of polynomial curve fitting [20, 21]. The fundamental idea is to take the voltage equation of the
machine,
d
V Ri (19)
dt
t
(V Ri )dt (20)
0
Where, V is the input voltage, i is the current, R is the resistance, and ψ is the flux linkage, respectively. Based
on the initial position, machine parameters, and relationship between the flux linkage and rotor position, the rotor
position can be estimated. At the very beginning of the integration the initial flux linkage has to be known
precisely to estimate the next step flux linkages. This means that the rotor has to be at a known position at the
start [14, 16, and 20]. Last equation (20) written in α-β coordinates depends on the terminal voltage and the
stator current. Using the α-β frame the equation for the rotor angle can be written as follows [14, 22]:
Li s
tan 1 ( s ) (21)
s Li s
where L is the winding inductance.
The actual rotor angle using the d-q frame can be calculated with [14, 22]:
tan 1 ( ds ) (22)
qs
This method also has an error accumulation problem for integration at low speeds. The method involves lots of
computation and is sensitive to the parameter variation. An expensive floating-point processor would be required
to handle the complex algorithm [20].
Because of the noise, in the last decade a pure investigation of the rotor position has gained less attention.
Solutions with adaptive or observer methods are more common [23, 24].
C. Position estimators based on back-EMF
In PM machines, the movement of magnets relative to the armature winding causes a motional EMF. The
EMF is a function of rotor position relative to winding, information about position is contained in the EMF
waveform [14].
Paper [25] propagates the determination of the back EMF without the aid of voltage probes which reduces
the cost of the system and improves its reliability. Instead of the measured voltages reference voltages are
used. The back EMF is not calculated by the integration of the total flux linkage of the stator phase circuits
because of the integrator drift problem. The estimation of the rotor position is given by the difference of the
arguments of the back EMF in the α-β reference frame and the arguments of the same one in the rotating d-
q frame:
es r
tan 1 ( ) tan 1 ( ) (23)
e s Lq i qs
Previous equation shows, that there is only a quadrature current dependency of the rotor position.
Furthermore the back-EMF in subject to the reference voltage in α-β coordinates can be described as
following function:
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s Rs i s
ƒ(s , s ) tan 1 ( ) (24)
s R s i s
The relation between the actual and reference voltages may be written in the form in which the variations
s and s are due to the phase difference.
*
s s s (25)
*
s s s (26)
Substituting from previous equations into equation (24), one gets:
儍
儍*
( s , s )
s s s s
*
( s , s )
* (27)
s Rs i s V
= tan ( 1
*
) rT
E
s R s i s
The second term in this equation is the dependent of the back EMF on the rotor speed. V, E and T are the
rms values of the stator voltages, the back EMF and the lag time introduced by the inverter respectively.
*
Thus, we get for the “estimated” position :
*
* s Rs i s
V
tan ( * 1
) rT tan 1 ( r ) (28)
s R s i s E Lq i qs
The proposed algorithm in [25] appears to be robust against parameter variation. Furthermore the electrical
drive has a good dynamic performance.
Many control methods suitable for SPMSM cannot be used directly to IPM. In the mathematical model of
the IPM, position information is included not only in the flux or EMF term but also in the changing
inductance because of its saliency. The model of SPMSM is a special symmetrical case of IPM, which is
relatively easy for mathematical procession. In order to apply the method suitable for SPM to a wide class
of motors, i.e. the IPM, in [26-28] a novel IPM models are suggested with an extended EMF (EEMF).
By rewriting motor voltage equations into a matrix form:
ds R s pLd - r Lq i ds
=
qs r Ld
R s pLq i qs
(29)
0
r r
There are two trigonometric functions of 2θ, which result from changing stator inductance. A reason why
2θ terms appear can be concluded as that the impedance matrix is asymmetrical. If the impedance matrix is
rewritten symmetrically as:
ds R s pLd - r Lq i ds
=
qs r Lq
R s pLd i qs
(30)
0
(Ld Lq )(r i ds pi qs ) r r
The circuit equation on α-β coordinate can be derived as follows, in which there is no 2θ term.
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s R s pLd r ( L d L q ) i s
= - (L L )
R s pLd i s
s r d q
(31)
sin
{( Ld Lq )(r i ds pi qs ) r r }
cos
The second term on the right side of (31) is defined as the extended EMF (EEMF). In this term, besides the
traditionally defined EMF generated by permanent magnet, there is a kind of voltage related to saliency of
IPMSM. It includes position information from both the EMF and the stator inductance. If the EEMF can be
estimated, the position of magnet can be obtained from its phase just like EMF in SPMSMs. Generally the
position estimation calculated from the EEMF [14, 18]:
e s
e
e s (32)
sin
{(Ld Lq )(r i ds pi qs ) r r }
cos
e s
tan 1 ( )
e s
(33)
(R s pLd )i s r (Ld Lq )i s
( s )
s (R s pLd )i s r (Ld Lq )i s
The problem is that, the EEMF is influenced by stator current ids and iqs, which vary during motor transient
state. This will cause troubles to the speed estimation. In the low speed range, the signal to noise ratio of
the EEMF is relatively small and the speed estimation result is still not so good. To overcome this difficulty
several authors uses observer and adaptive methods [14].
3.1.2 Adaptive Methods
In this category, various types of observers are used to estimate rotor position. The fundamental idea is that
a mathematical model of the machine is utilized and it takes measured inputs of the actual system and
produces estimated outputs. The error between the estimated outputs and measured quantities is then fed
back into the system model to correct the estimated values adaptation mechanism. The biggest advantage of
using observers is that all of the states in the system model can be estimated including states that are hard to
obtain by measurements. Also, in the observer based methods, the error accumulation problems in the flux
calculation methods do not exist [20], but the weakness is poor speed adjustable at low speed, complicated
algorithm and huge calculation [2]. Observers have been implemented in sensorless PM motor drive
systems. The adaption mechanism base on the following three methods criteria of super stability theory
(Popov), kalman filter, and method of least error square [29]. Methods using the Popov are criteria model
reference adaptive system and luenberger observer.
A. Estimator Based on Model Reference Adaptive System
A model reference adaptive system (MRAS) can be represented by an equivalent feedback system as shown
in Figure 2.
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us
Reference x +
is Model
-
Adaptive
Model
ˆ
y Adaptation
mechanism
Figure 2. Rotor speed estimation structure using MRAS.
Where represents the error between the reference model and the adaptive model. The difference between
real and estimated value can be expressed with the dynamic error equation [29]:
d d ˆ
(x x ) Ax Ax K (Cx Cx )
垐 ?
dt dt (34)
(A - KC ) (A - A ˆˆ )x
Where x is the state vector, u the system input vector, y the output vector, the matrices A , B and C the
parameter of the PMSM and the matrix K a gain coefficient respectively. All elements with ^ are the
estimated vectors and matrices.
It should be noted that, speed estimation methods using MRAS can classified into various types according
to the state variables. The most commonly used are the rotor flux based MRAS, back-emf based MRAS,
and stator current based MRAS. For all mentioned states can be applied one adaption model [29]:
T
y k p (x q x d x q x d ) k i (x q x d x q x d ) dt (35)
垐 垐 ?
0
Stability and speed of the calculation of ˆ
y depends on the proportional and integral part of (35). x q and
x d represent the states of the PMSM in quadrature and direct coordinates.
As the rotor speed is included in current equations, we can choose the current model of the PMSM as the
adaptive model, and the motor itself as the reference model. These two models both have the output i ds
and i qs , According to the difference between the outputs of the two models, through a certain adaptive
mechanism, we can get the estimated value of the rotor speed. Then the position can be obtained by
integrating the speed [30].
The equations (1) to (4) can be written as below form:
di ds
Ld -R s i ds Lq i qs ds (36)
dt
di
Lq qs -R s i qs - Ld i ds - r qs (37)
dt
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The d-q axis currents i ds , i qs are the state variables of the current model of the PMSM, which is described
by (36) and (37).
By rewriting equations (36) and (37) into a matrix form as below:
R L
r s q r
d i ds Ld Ld i ds
Ld Ld
dt L Rs
i qs
-
d
i qs
Lq
Lq
(38)
ds R s r
L L
d d
qs
Lq
For the convenience of stability analysis, the speed has been confined to the system matrix:
Rs Lq
Ld Ld
A (39)
Ld R
- s
Lq
Lq
To be simplified, define:
r
x 1 i ds
x Ld
(40)
x2
i qs
ds R s r
L
u1 Ld d
u (41)
u 2 qs
Lq
Then the reference model can be rewritten as:
d
x Ax u (42)
dt
The adaptation mechanism uses the rotor speed as corrective information to obtain the adjustable parameter
current error between two models in order to drive the current error to zero, when we can take the
estimation value as a correct speed. The process of speed estimation can be described as follows:
Rs Lq
ˆ
垐
d x 1 Ld
Ld x 1 u1
?
垐 R x u
(43)
dt x 2 Ld
s 2 2
?
- ˆ
Lq
Lq
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Where is to be estimated, (43) can be simplified as below:
ˆ
d
垐 ˆ
x Ax u? (44)
dt
The error of the state variables is:
e x x ˆ (45)
According to equation (42) and (44), estimation equation can be written as:
d
e Ae Iw (46)
dt
De (47)
ˆ
Where w (A A )x , choose D I , then
ˆ
Ie e (48)
According to Popov super stability theory, if
(1) H (s ) D (SI - A )1 is a strictly positive matrix,
t0
(2) (0, t 0 ) T wdt , t 0 0 , where 02 is a limited positive number, then lim e (t ) 0 .
t
0
The MARS system will be stable.
Finally, the equation of can be achieved as:
ˆ
t
k 1 (x 1x 2 x 2 x 1 ) dt
ˆ 垐
0 (49)
k 2 (x 1x 2 x 2 x 1 ) (0)
垐 ˆ
Where k1, k 2 ≥ 0
Replacing x with i :
t
r
k 1 (i ds i垐 i qs i ds
ˆ qs (i qs i? ))dt
qs
0
Ld
(50)
r
k 2 (i ds i垐 i qs i ds
qs (i qs i? )) (0)
qs
ˆ
Ld
In the equation (50), iˆds , iˆqs can be calculated through the adjustable model, i ds , i qs can be obtained by
the transformation of the measured stator currents.
The rotor position can be obtained by integrating the estimated speed:
t
ˆ
dt
ˆ (51)
0
The MRAS scheme is illustrated in Figure 3.
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uαs iαs ids
Coordinate
uβs PMSM iβs iqs
Transform
uds iˆds
Coordinate Adjustable
Transform uqs Model iˆqs
ˆ
t
r
k 1 (i ds iˆqs i qs iˆds
ˆ (i qs iˆqs ))dt
ˆ
0
Ld
r
k 2 (i ds iˆqs i qs iˆds (i qs iˆqs )) (0)
ˆ
Ld
Figure 3. Control block scheme of MRAS
B. Observer-Based Estimators
Observer methods use instead of the reference model the real motor. The observer is the adaptive model
with a constantly updated gain matrix K which is selected by choosing the eigenvalues in that way, that the
system will be stable and that the transient of the system will be dynamically faster than the PM machine
[29].
1) Luenberger Observer
A full order state observer with measureable estimated state variables, generally stator current, and not
measurable variables like rotor flux linkages, back-EMF and rotor speed can be described in the form of
state space equations for control of time invariant systems [29]:
x Ax Bu
(52)
y Cx
where A is the state matrix of the observer a function of the estimated rotor speed, B the input matrix and C
output matrix.
In the following example the estimation algorithm observer based on back-EMF in α-β frame is considered.
With the assumption that the back-EMF vector has the following form:
e s
e
e s (53)
sin
{(Ld Lq )(r i ds pi qs ) r r }
cos
and that electrical systems time constant is much smaller than the mechanical one. r is regarded as a
constant parameter. The linear state equation can be described as follows [26, 28, and 29]:
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d i s i s
A B u s
W (54)
dt e s
e s
i s
i s C . (55)
e s
Where,
i s [i s i s ]T , e s [e s e s ]T
Rs - r ( L d L q ) -1 0
1 r ( Ld Lq ) Rs 0 -1
A
Ld 0 0 0 - r
0
0 r 0
1 0
1 0 1 1 0 0 0
B ,C
Ld 0 0 0 1 0 0
0 0
晻 ? sin
W (Ld Lq )(r i ds i qs )
cos
The term W is the unknown linearization error and appears only, when i ds or i qs is changing.
The state equation of the Luenberger observer can be written as:
i垐s u s
d
A ˆ i s B
dt 垐
e s e s
u s
(56)
K ( i iˆ
s s )
iˆ s
iˆ s C . (57)
ˆ
e s
ˆ
Where ^ denotes estimated values. A is a function of the rotor speed. Therefore the speed r must also be
estimated. The estimated speed can be calculated with a PI-controller which has the form of equation (58).
r k p (es e s ) k i (es e s ) dt (58)
垐 垐 ?
Where k p and k i are proportional and integral gain constants respectively, i s iˆ s and
i s iˆ s are the α-β axis current errors respectively. For obtaining error dynamic (34) can be used. It
can be seen, that the dynamics are described by the eigenvalues of A - KC . To determine the stability of
the error dynamics of the observer it can be used Popov’s super stability theorem or Lyapunov’s stability
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theorem which gives a sufficient condition for the uniform asymptotic stability of non-linear system by
using the Lyapunov function V. A sufficient condition for the uniform asymptotic stability is that the
derivate of V is negative definite. If the observer gain K is chosen that (A - KC )T is negative semi-
definite, then the speed observer will be stable [29].
Further literature in flux-based observer can be found in [31, 32].
Systems with a Luenberger observer generally have a better performance than MRAS based Systems.
MRAS based systems have a higher error in the estimated values. Furthermore, the Luenberger approach
has a less tendency to oscillate in the range of low speed and need in comparison with the kalman Filter
method less computation time and memory requirement [29, 33].
2) Reduced Order Observer
Paper [34] is included on the idea of the reduced order observer. The design method considers a general
dynamic system in the form of equation (52).
Where the pair (C, A) is observable. If the output y can be written as a combination of the state vector as:
y C 1x 1 C 2 x 2 ; det(C 2 ) 0 (59)
ˆ
Then, it is sufficient to design an observer for the partial state x 1 . If x 1 is the estimate of x 1 , the partition
x 2 of the state vector can be calculated as:
x 2 C 21 ( y C 1x 1 )
垐 (60)
The reduced order observer allows for order reduction, is simpler to implement and the state partition x 2 is
found using the algebraic equation (60).
The design methodology of the reduced order observer requires transformation of the original system to the
form:
x 1 A11x 1 A12 y B1u (61)
y A21x 1 A22 y B 2u (62)
A new variable x is introduced:
x x 1 L1 y (63)
where L1 is a nonsingular gain matrix. After the differentiation and algebraic manipulation of (63), the
following form is obtained:
x (A11 L1A 21 )x (A12 L1A 22 A11L1 L1A 21L1 ) y
(64)
( B 1 L1B 2 )u
An observer for x is designed in the form:
ˆ
x ( A11 L1A 21 )x (A12 L1A 22 A11L1 L1A 21L1 ) y
ˆ
(65)
( B 1 L1B 2 )u
After subtraction, the dynamics of the mismatch is:
x (A11 L1A 21 )x (66)
With the known matrices A11 and A21, the gains in L1 can be selected to obtain desired eigenvalues.
ˆ
Therefore, the mismatch tends to zero with the desired rate of convergence. Once x ' has been estimated,
the state partition x 1 follows from (63) and x 2 is calculated using (60).
Further literature in reduced order observer can be found in [35-37].
3) Sliding Mode Observer
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In [38, 39] present a sliding mode observer (SMO) for the estimation of the EMFs and the rotor position of
the PMSM. The observer is constructed based on the full PMSM model in the stationary reference frame.
The proposed sliding mode observer is developed based on the equations of the PMSM with respect to the
currents and EMFs:
pe s e s (67)
pe s e s (68)
Rs 1 1
pi s i s e s s (69)
L L L
R 1 1
pi s s i s e s s (70)
L L L
The voltages s , s and currents i s , i s are measured and considered known. In the observer, a speed
estimate is used according to (71); the speed estimate is considered different than the real speed (note
that is unknown).
ˆ (71)
The observer equations are:
pes ( )e s l11us
垐 (72)
pe s ( )e s l 22 u s
垐 (73)
R 1 1 1
pi垐 s i s e s s u s
s
ˆ (74)
L L L L
Rs 1 1 1
pi垐 i s e s s u s
s
ˆ (75)
L L L L
where the switch (sliding mode) controls u s , u s are:
u M . sign (s )
s s iˆ i
s s
; (76)
u s M . sign (s ) s iˆ s i s
Note that M is a design gain, M> 0; l11 and l22 are design parameters. After the original equations (67) to
(70) are subtracted from (72) to (75), system is obtained by following equations:
pe s e s e s l11u s
ˆ (77)
pe s e s e s l 22 u s
ˆ (78)
Rs 1 1
s s e s u s (79)
L L L
Rs 1 1
s s es u s (80)
L L L
In the last two equations (79) and (80), note that if the sliding mode gain M is high enough, the
manifolds s , s and their time derivatives have opposite signs. As a result, the manifolds tend to zero and
sliding mode occurs; i.e. s 0 and s 0 . Once sliding mode starts, s , s and their derivatives are
identically equal to zero. The equivalent controls are:
u s ,eq e s
(81)
u s ,eq e s
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In order to study the behavior of the mismatches e s , e s , the terms u s and u s are replaced with the
equivalent controls in the first two equations of (77) and (78). The resulting dynamics of the EMF
mismatches is:
pe s e s e s l11e s
ˆ (82)
pe s e s e s l 22 e s
ˆ (83)
Next, select the candidate Lyapunov function which is positive definite, V> 0.
1
V (e s 2 e s 2 ) (84)
2
After differentiation, the expression of V is:
V e s e s e s e s (85)
After replacing the derivatives from (82) and (83), this becomes:
V l11e s 2 l 22 e s 2 e s e s e s e s (86)
垐
If l11 l 22 k where k 0 , the derivative of V is:
V k (e s 2 e s 2 ) (e s e s e s e s ) (87)
垐
Equation (87) will be used to study the convergence of the observer. Note that V 0 If 0 and the
observer is asymptotically stable. There are two terms in (87): the first one is always negative (and can be
increased using the design parameter k) while the second one has unknown sign. As long as the mismatches
e s and e s are significant, the first term overcomes the second and V is negative (as a result, function
V decays). The Lyapunov function stops decaying when V 0 and this is equivalent to:
k (e s e s ) (e s e s e s e s )
2 2
垐 (88)
Since the mismatches e s , e s should be of the same order of magnitude, using the notation me s e s
(where m is unknown), equation (88) is manipulated to give the value of the mismatch e s at which the
function V stops decaying:
m e s e s
垐
e s (89)
k (1 m 2 )
The Lyapunov function settles to the vicinity given by the mismatch in (89), and the size of this vicinity
(and the mismatch) can be reduced by increasing k (which is a design parameter). The analysis shows that
the influence of the speed mismatch (caused by the speed observer) can be made irrelevant by proper
design of the SM observer gains; the mismatch between the real and estimated EMFs can be made as small
as desired according to (89). Once the EMFs have been found, the rotor position is computed directly with:
ˆ ˆ
e s
tan 1 ( ) (90)
ˆ
es
Further literature in sliding mode observer (SMO) can be found in [40-43].
The main difference between the Luenberger and the Sliding mode observer (SMO) lies in the observer
structure. The SMO uses a sign-function of the estimation error instead of the linear value as correction
feedback [44].
4) Kalman Filter
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The kalman filter is in principle a state observer that establishes the approximation for the state variables of
a system, by minimization of the square error, subjected at both its input and output to random
disturbances. If the dynamic system of which the state is being observed is non-linear, then the kalman
filter is called an extended kalman filter (EKF). The EKF is basically a full-order stochastic observer for the
recursive optimum state estimation of a nonlinear dynamical system in real time by using signals that are in
noisy environments. The EKF can also be used for unknown parameter estimation or joint state [45]. The
linear stochastic systems are described by relations [7]:
x (t ) Ax (t ) Bu (t ) w (t ) ; x (t o ) x o (91)
y (t ) Cx (t ) (92)
z (t ) y (t ) (t ) (93)
Where:
x , y , u , A , B , C have the significance known from deterministic system; w (t ) represents the vector
of disturbances applied at the system input; z (t ) is the vector of the measurable outputs, affected by the
random noise (t ) .
w (t ) includes some uncertainties referring
It can be considered that, besides the input disturbances, vector
to the process model. It will be assumed that the vector functions w (t ) and (t ) are not correlated and
zero-mean stochastic processes. From statistic point of view, the stochastic processes w (t ) and (t ) are
characterized by the covariance matrices Q and R, respectively. It is further assumed that the initial state
x o is a vector of random variables, of mean x o and covariance P0 , not correlated with the stochastic
processes w (t ) and (t ) over the entire interval of estimation.
The covariance matrices Q, R, P0 characterizing the noise sources of system (94)-(96) are, by definition,
symmetrical and positively semi-definite, of dimensions (n x n), (m x m) and (n x n) respectively, where n
and m represent the number of state and output variables, respectively.
For linear time invariant systems, the following relations of recurrent computation describe the general
form of the kalman filter implementation algorithm:
K k Pk k 1C T (CPk k 1C T R )1 (94)
x k k x k k 1 K k ( y k Cx k k 1 )
垐 ? (95)
Pk k (I n - K k C )Pk k 1 (96)
x k 1 k Ad x k k T s Bu k
垐 (97)
Pk 1 k Ad Pk k Ad T Q (98)
Where Ts represents the sampling period and Ad is the matrix of the discrete linearized system:
Ad I n T s A (99)
In these relationships, the (n x m) matrix K represents the kalman gain; P represents the covariance state
matrix and In is the (n x n) unit matrix. In the recurrent computation relationships, the subscript index
notations of type k/k-1 show that the respective quantities (state vectors or their covariance matrices) are
computed for sample k, using the values of similar quantities from the previous sample.
For non-linear stochastic systems, the dynamic state model is described by the following expressions:
x (t ) f (x (t ),u (t ), t ) w (t ) (100)
y (t ) h (x (t ), t ) (101)
z (t ) h (x (t ),t ) (t ) (102)
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where f and h are (n x 1) and (m x 1) function vectors, respectively. The A and C matrices of the EKF
structure are dependent now upon the state of the system and are determined by:
f (x (t ),u (t ), t )
A (x (t ), t )
ˆ x (t ) x (t )
ˆ (103)
x T (t )
h (x (t ), t )
C (x (t ), t )
ˆ x (t ) x (t )
ˆ (104)
x T (t )
Additionally to the fact that matrices A and c have now become dependent on the state of the system, the
algorithm suffers some further changes, which affect relationships (95) and (97), now expressed as:
x k k x k k 1 K k [ y k h (x k k 1 )]
垐 ? (105)
x k 1 k x k k T s f (x (t ),u (t ))
垐 ? (106)
The kalman filter algorithm is initiated by adopting adequate values for the covariance matrix of the initial
state P0 P0 1 , as well as for the weighting matrices Q and R, the latter two being constant during the
estimation.
EKF is known for its high convergence rate, which significantly improves transient performance. However,
the long computation time is a main drawback of the EKF [45]. Although last-generation floating-point
digital signal processors can easily overcome the EKF real-time calculations [46], this is not suitable for
low-cost PMSM applications. Moreover, long computation requirements disturb other program service
routines such as fault diagnosis or custom programs installed in products. [47] presents the optimal two-
stage kalman estimator (OTSKE) which is composed of two parallel filters: a full order filter and another
one for the augmented state. This estimator has the advantage of reducing the computational complexity
compared to the classical EKF.
The application of the EKF in the sensorless PMSM drive system will be increased a lot [29, 48]. The main
steps for a speed and position sensorless PMSM drive implementation using a discredited EKF algorithm
can be found in [45, 48-51].
3.2 Saliency and Signal Injection Methods
In signal injection methods, the feature of salient-pole PMSMs such that the inductance varies with the
rotor position is used. High frequency voltage or current signal is injected on the top of the fundamental,
and signal processing (vector filters with inevitable time delay) is employed to extract currents harmonics
that contain rotor position. Thus, the position can be estimated even at standstill and low speeds, robustly to
parameter variations [52]. For wide speed range, hybrid methods are used [53]. High frequency signal
injection techniques, Figure 4, are considered to be superior to other sensorless control schemes of ac
machines for low and zero speed operation.
Fundamental
excitation
PWM AC Band pass Heterodyning Speed
ˆ
High Inverter Machine filter demodulation estimation
frequency
signal
Position ˆ
estimation
Figure 4. High frequency signal injection block diagram
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Based on the injection direction of the excitation signal, the high frequency injection schemes could be
classified as rotating injection method, in which the carrier signal is a rotating sinusoidal signal in the
stationary reference frame; pulsating injection method, in which an ac voltage signal is injected on the
estimated rotor d-axis, rotating with the rotor and the rotor position offset could be observed from the high
frequency component of the estimated q-axis current. However, the drive efficiency of the schemes is hard
to be accessed and the development of the sensorless strategies suffers the unknown nonlinearity of the
model [54].
Other methods are based on the signal processing of PWM excitation without signal injection. The SV-
PWM waveforms provide sufficient excitation to extract the position signal from the stator current. These
methods are: Indirect Flux detection by On-line Reactance Measurement (INFORM) method, and methods
based on the measurements of di/dt of the stator currents induced by SV-PWM. Typically, the injected
signal is a sinusoidal type. To eliminate the time delay introduced by filters, a new square wave signal
injection method is proposed, based only on the measurement of the corresponding induced stator current
variations, which leads to high dynamics and robust position estimation [52].
Magnetic saliency methods are relatively complicated for real time implementation and are less portable
from one machine to another; however, they work well at low speed. The rotor position of the PMSM can
also be estimated at standstill; as a result, the motor can be started with the correct rotor position from the
beginning of the motion [38].
Further literatures which use the magnetic saliency methods can be found in [55-58].
3.3 Artificial Intelligence Methods
Artificial intelligence describe neural network (NN), fuzzy logic based systems (FLS) and fuzzy neural
networks (FNN). The use of artificial intelligence (AI) to identify and control nonlinear dynamic systems
has been proposed because they can approximate a wide range of nonlinear functions to any desired degree
of accuracy [59]. Moreover, they have been the advantages of immunity from input harmonic ripples and
robustness to parameter variations. However, ANN controller synthesis requires design of the control
structure which includes selecting the neural network structure, weight coefficients and activation function.
The selection of neural structure as the initial step is done by trial and error method since there is no proper
procedure for this [60]. The complex of the selected neural network structure is a compromise between the
high quality of control robustness and the possibility of control algorithm calculation in real time. This
gives rise to inaccuracies [60]. Recently, there have been some investigations into the application of AI to
power electronics and ac drives, including speed estimation [60-63].
Paper [64] presents a robust control strategy with NN flux estimator for a position sensorless SPMSM
drive. In the proposed algorithm stator flux is estimated from stationary α-β axis stator currents and speed
error, Eω. An equivalent Recurrent Neural Network (RNN) is then proposed which results in the following
matrix equation:
s ( k 1) W 11 0 s ( k ) W 13
( k 1) 0 W ( k ) W i s ( k )
s 22 s 23 (107)
W 14 W 15
i s (k ) E w (k )
W 24 W 25
where, W11 , W13 ,W22 , W23 , W14 etc. are the weights of the RNN.
The estimated stator flux using RNN is used to find out the rotor position as following:
(108)
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Where, is the flux angle, and is the torque angle. Where tan 1 ( s )
s
4. Parameter Adaptation
Motion-sensorless PMSM drives may have an unstable operating region at low speeds. Since the back
electromotive force (EMF) is proportional to the rotational speed of the motor, parameter errors have a
relatively high effect on the accuracy of the estimated back EMF at low speeds [65]. Improper observer
gain selections may cause unstable operation of the drive even if the parameters are accurately known [66].
In practice, the stator resistance varies with the winding temperature during the operation of the motor, so
there is often a mismatch between the actual winding resistance and its corresponding value in the model
used for speed estimation. This may lead not only to a substantial speed estimation error but to instability as
well.
Parameter variation not only degrades the control performance but also causes an error in the estimated
position [67]. As consequence, numerous online schemes for parameter identification have been proposed,
recently [65-69].
5. Conclusion
Recently, permanent magnet synchronous motor (PMSM) drives are replacing classic dc and induction
machine drives in a variety of industrial applications. PMSM drive research has been concentrated on the
elimination of the mechanical sensors at the motor shaft without deteriorating the dynamic performances of
the drive. Many advantages of sensorless ac drives such as reduced hardware complexity, low cost, reduced
size, cable elimination, increased noise immunity, increased reliability and decreased maintenance.in this
paper, a review of different speed and rotor position estimation schemes of PMSM drives has been
introduced. Each method has its advantages and disadvantages. Although numerous schemes have been
proposed for speed and rotor position estimation, many factors remain important to evaluate their
effectiveness. Among them are steady state error, dynamic behavior, noise sensitivity, low speed operation,
parameter sensitivity, complexity, and computation time. In particular, zero-speed operation with
robustness against parameter variations yet remains an area of research for speed sensorless control.
As a final comment, each speed estimation method of sensorless application requires a specific design,
which takes into consideration the required performance, the available hardware and the designer skills.
References:
[1] S. Yu, Z. Yang, S. Wang and K. Zheng, "Sensorless Adaptive Backstepping Speed Tracking Control of
Uncertain Permanent Magnet Synchronous Motors", in Conf. Rec., IEEE-ISCAA, June 2010, pp. 1131-
1135.
[2] Q. Gao, S. Shen, and T. Wang, "A Novel Drive Strategy for PMSM Compressor", in Conf. Rec., IEEE-
ICECE, June 2010, pp. 3192 – 3195.
[3] Z. Peroutka, K. Zeman, F. Krus, and F. Kosten, "New Generation of Trams with Gearless Wheel
PMSM Drives: From Simple Diagnostics to Sensorless Control", in IEEE Conf. Rec., 14th International
Power Electronics and Motion Control Conference EPE-PEMC, September 2010, pp. 31-36.
[4] H. Peng, H. Lei, and M. Chang-yun, "Research on Speed Sensorless Backstepping Control of
Permanent Magnet Synchronous Motor", in Conf. Rec., IEEE-ICCASM, October 2010, Vol. 15, pp.
609-612.
[5] J. Sung Park, S. Hun Lee, C. Moon, and Y. Ahn Kwon, "State Observer with Stator Resistance and
Back-EMF Constant Estimation for Sensorless PMSM", IEEE Region 10 Conference, TENCON 2010,
November 2010, pp. 31-36.
[6] T. J. Vyncke, R. K. Boel and J. A. A. Melkebeek, "Direct Torque Control of Permanent Magnet
Synchronous Motors – An Overview", 3rd IEEE Benelux Young Researchers Symposium in Electrical
Power Engineering, April 2006, pp. 1-5.
62
20. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 5, 2011
[7] V. Comnac, M. N. Cirstea, F. Moldoveanu, D. N. Ilea, and R. M. Cernat, "Sensorless Speed and Direct
Torque Control of Interior Permanent Magnet Synchronous Machine Based on Extended Kalman
Filter", in Proc. of the IEEE-ISIE Conf., Vol. 4, November 2002, pp. 1142-1147.
[8] M. S. Merzoug, and F. Naceri, "Comparison of Field-Oriented Control and Direct Torque Control for
Permanent Magnet Synchronous Motor (PMSM)", in World Academy of Science, Engineering and
Technology, Vol. 48, 2008, pp. 299-304.
[9] Y. Xu, and Y. Zhong, "Speed Sensorless Direct Toque Control of Interior Permanent Magnet
Synchronous Motor Drive Based on Space Vector Modulation", in Conf. Rec., IEEE-ICECE, June
2010, pp. 4226-4230.
[10] J. Arellano-Padilla, C. Gerada, G. Asher, and M. Sumner, "Inductance Characteristics of PMSMs and
their Impact on Saliency-based Sensorless Control", in IEEE Conf. Rec., 14th International Power
Electronics and Motion Control Conference EPE-PEMC, September 2010, pp. 1-9.
[11] K. Jezernik, R. Horvat, "High Performance Control of PMSM ", in Conf. Rec., IEEE-SLED, July
2010, pp. 72-77.
[12] S. Sumita, K. Tobari, S. Aoyagi, and D. Maeda, "A Simplified Sensorless Vector Control Based on
the Average of the DC Bus Current", in Conf. Rec., IEEE-IPEC, June 2010, pp.3035-3040.
[13] R. Mustafa, Z. Ibrahim and J. Mat Lazi, "Sensorless Adaptive Speed Control for PMSM Drives", in
IEEE Conf. Rec., 4th International Power Engineering and Optimization Conf., PEOCO'10, June 2010,
pp. 511-516.
[14] O. Benjak, and D. Gerling, "Review of Position Estimation Methods for IPMSM Drives Without a
Position Sensor Part I: Nonadaptive Methods", in Conf. Rec., IEEE-ICEM, September 2010, pp. 1-6.
[15] M. A. Jabbar, M. A. Hoque, and M. A. Rahman, "Sensorless Permanent Magnet Synchronous Motor
Drives", IEEE Canadian Conference on Electrical and Computer Engineering, CCECE'97, Vol. 2, May
1997, pp. 878-883.
[16] J. P. Johnson, M. Ehsani, and Y. Guzelgunler, "Review of Sensorless Methods for Brushless DC", in
Conf. Rec., IEEE-IAS'99, Annual Meeting, Vol. 1, October 1999, pp. 143-150.
[17] S. Kondo, A. Takahashi and T. Nishida, "Armature Current Locus Based Estimation Method of Rotor
Position of Permanent Magnet Synchronous Motor without Mechanical Sensor", in Conf. Rec., IEEE-
IAS'95, Annual Meeting, Vol. 1, October 1995, pp. 55-60.
[18] L. Yongdong, and Z. Hao, "Sensorless Control of Permanent Magnet Synchronous Motor – A
Survey", in Conf. Rec., IEEE-VPPC'08, September 2008, pp. 1-8.
[19] T. D. Batzel, and K. Y. Lee, "Electric Propulsion with the Sensorless Permanent Magnet
Synchronous Motor: Model and Approach", IEEE Transactions on Energy Conversion, Vol. 20, No. 4,
December 2005, pp. 818-825.
[20] T. Kim, H. Lee, and M. Ehsani, "State of the Art and Future Trends in Position Sensorless Brushless
DC Motor/Generator Drives", Proc. of the 31th Annual Conference of the IEEE-IECON, November
2005, pp. 1718-1725.
[21] N. Bekiroglu, S. Ozcira, "Observerless Scheme for Sensorless Speed Control of PMSM Using Direct
Torque Control Method with LP Filter", Advances in Electrical and Computer Engineering (AECE),
Vol. 10, No. 3, August 2010, pp. 78-83.
[22] D. Yousfi, A. Halelfadl, and M. EI Kard, "Sensorless Control of Permanent Magnet Synchronous
Motor", in Conf. Rec., IEEE-ICMCS'09, April 2009, pp. 341-344.
[23] D. Paulus, J.-F. Stumper, P. Landsmann, and R. Kennel, "Robust Encoderless Speed Control of a
Synchronous Machine by direct Evaluation of the Back-EMF Angle without Observer", in Conf. Rec.,
IEEE-SLED, July 2010, pp. 8-13.
[24] S. Shimizu, S. Morimoto, and M. Sanada, "Sensorless Control Performance of IPMSM with Over-
modulation Range at High Speed", in Conf. Rec., IEEE-ICEMS'09, November 2009, pp. 1-5.
[25] F. Genduso, R. Miceli, C. Rando, and G. R. Galluzzo, "Back EMF Sensorless-Control Algorithm for
High-Dynamic Performance PMSM", IEEE Transactions on Industrial Electronics, Vol. 57, No. 6, June
2010, pp. 2092-2100.
[26] Z. Chen, M. Tomita, S. Doki, and S. Okuma, "An Extended Electromotive Force Model for
Sensorless Control of Interior Permanent Magnet Synchronous Motors", IEEE Transactions on
Industrial Electronics, Vol. 50, No. 2, April 2003, pp. 288-295.
63
21. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 5, 2011
[27] S. Morimoto, K. Kawamoto, M. Sanada, and Y. Takeda, "Sensorless Control Strategy for Salient-
Pole PMSM Based on Extended EMF in Rotating Reference Frame", IEEE Transactions on Industry
Applications, Vol. 38, No. 4, July/August 2002, pp. 1054-1061.
[28] S. Ichikawa, Z. Chen, M. Tomita, S. Doki, and S. Okuma, "Sensorless Control of an Interior
Permanent Magnet Synchronous Motor on the Rotating Coordinate Using an Extended Electromotive
Force", Proc. of the 27th Annual Conference of the IEEE-IECON, Vol. 3, November/December 2001,
pp. 1667-1672.
[29] O. Benjak, D. Gerling, "Review of Position Estimation Methods for IPMSM Drives without a
Position Sensor Part II: Adaptive Methods", in Conf. Rec., IEEE-ICEM, September 2010, pp. 1-6.
[30] Y. Shi, K. Sun, H. Ma, and L. Huang, "Permanent Magnet Flux Identification of IPMSM based on
EKF with Speed Sensorless Control", Proc. of the 36th Annual Conference of the IEEE-IECON,
November 2010, pp. 2252-2257.
[31] T. F. Chan, W. Wang, P. Borsje, Y. K. Wong, and S. L. Ho, "Sensorless permanent-magnet
synchronous motor drive using a reduced-order rotor flux observer", Electric Power Applications, IET,
Vol. 2, No. 2, March 2008, pp. 88-98.
[32] P. Vaclavek, and P. Blaha, "PMSM Position Estimation Algorithm Design based on the Estimate
Stability Analysis", in Conf. Rec., IEEE-ICEMS'09, November 2009, pp. 1-5.
[33] B. S. Bhangu, and C. M. Bingham, "GA-tuning of Nonlinear Observers for Sensorless Control of
Automotive Power Steering IPMSMs", in Conf. Rec., IEEE-VPPC, September 2005, pp. 772-779.
[34] M. Comanescu, and T. D. Batzel, "Reduced Order Observers for Rotor Position Estimation of
Nonsalient PMSM", in Conf. Rec., IEEE-IEMDC'09, May 2009, pp. 1346-1351.
[35] D. Yousfi, A. Halelfadl, and M. EI Kard, "Review and Evaluation of Some Position and Speed
Estimation Methods for PMSM Sensorless Drives ", in Conf. Rec., IEEE-ICMCS'09, April 2009, pp.
409-414.
[36] C. H. De Angelo, G. R. Bossio, J. A. Solsona, G. O. Garcia, and M. I. Valla, "Sensorless Speed
Control of Permanent Magnet Motors Driving an Unknown Load", in Conf. Rec., IEEE-ISIE'03, Vol. 1,
June 2003, pp. 617-620.
[37] S. Ichikawa, C. Zhiqian, M. Tomita, S. Doki, and S. Okuma, "Sensorless Control of an Interior
Permanent Magnet Synchronous Motor on the Rotating Coordinate Using an Extended Electromotive
Force", Proc. of the 27th Annual Conference of the IEEE-IECON, Vol. 3, November/December 2001,
pp. 1667-1672.
[38] M. Comanescu, "Rotor Position Estimation of PMSM by Sliding Mode EMF Observer under
improper speed", in Proc. of the IEEE-ISIE Conf., July 2010, pp. 1474-1478.
[39] M. Comanescu, "Cascaded EMF and Speed Sliding Mode Observer for the Nonsalient PMSM", Proc.
of the 36th Annual Conference of the IEEE-IECON, November 2010, pp.792-797.
[40] M. Ezzat, J. de Leon, N. Gonzalez, and A. Gluminea, "Observer-Controller Scheme using High Order
Sliding Mode Techniques for Sensorless Speed Control of Permanent Magnet Synchronous Motor",
Proc. of the 49th Conference of the IEEE-CDC, December 2010, pp. 4012-4017.
[41] Y. Nan, and T. Zhang, "Research of Position Sensorless Control for PMSM Based on Sliding Mode
Observer", 2nd international conference of the IEEE-ICISE, December 2010, pp. 5282-5285.
[42] L. Jun, W. Gang, and Y. JinShou, "A Study of SMO Buffeting Elimination in Sensorless Control of
PMSM", in Proc. of the IEEE-WCICA Conf., July 2010, pp. 4948-4952.
[43] Zhang Niaona, Guo yibo and Zhang Dejiang, "Sliding Observer Approach for Sensorless Operation
of PMSM Drive", in Proc. of the IEEE-WCICA Conf., July 2010, pp. 5809-5813.
[44] L. Jiaxi, Y. Guijie, and L. Tiecai, "A New approach to Estimated Rotor Position for PMSM Based on
Sliding Mode Observer", in Conf. Rec., IEEE-ICEMS'07, October 2007, pp. 426-431.
[45] J. Jang, B. Park, T. Kim, D. M. Lee, and D. Hyun, "Parallel Reduced-Order Extended Kalman Filter
for PMSM Sensorless Drives", Proc. of the 34th Annual Conference of the IEEE-IECON, November
2008, pp. 1326-1331.
[46] S. Bolognani, R. Oboe, and M. Zigliotto, "Sensorless Full-Digital PMSM Drive with EKF Estimation
of Speed and Rotor Position", IEEE Transactions on Industrial Electronics, Vol. 46, No. 1, February
1999, PP. 184-191.
64
22. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 5, 2011
[47] A. Akrad, M. Hilairet, and D. Diallo, "Performance Enhancement of a Sensorless PMSM drive with
Load Torque Estimation", Proc. of the 36th Annual Conference of the IEEE-IECON, November 2010,
pp. 945-950.
[48] T. J. Vyncke, R. K. Boel, and J. A. A. Melkebeek, "On Extended Kalman Filters with Augmented
State Vectors for the Stator Flux Estimation in SPMSMs", in Proc. of the Twenty-Fifth Annual IEEE-
APEC Conf., February 2010, pp. 1711-1718.
[49] A. Titaouinen, F. Benchabane, o. Bennis, K. Yahia, and D. Taibi, "Application of AC/DC/AC
Converter for Sensorless Nonlinear Control of Permanent Magnet Synchronous Motor", in Conf. Rec.,
IEEE-SMC, October 2010, pp. 2282-2287.
[50] F. Benchabane, A. Titaouine, o. Bennis, K. Yahia, and D. Taibi, "Systematic Fuzzy Sliding Mode
Approach Combined With Extented Kalman Filter for Permanent Magnet Synchronous Motor control",
in Conf. Rec., IEEE-SMC, October 2010, pp. 2169-2174.
[51] S. Carriere, S. Caux, M. Fadel, and F. Alonge, "Velocity sensorless control of a PMSM actuator
directly driven an uncertain two-mass system using RKF tuned with an evolutionary algorithm", in
Proc. of the IEEE-(EPE/PEMC) Conf., September 2010, pp. 213-220.
[52] G.-D. Andreescu and C. Schlezinger, "Enhancement Sensorless Control System for PMSM Drives
Using Square-Wave Signal Injection", Proceedings of the International Symposium on Power
Electronics, Electrical Drives, Automation and Motion (SPEEDAM), June 2010, pp. 1508-1511.
[53] D. Xiao, G. Foo, and M. F. Rahman, "A New Combined Adaptive Flux Observer with HF Signal
Injection for Sensorless Direct Torque and Flux Control of Matrix Converter Fed IPMSM over a Wide
Speed Range", IEEE Energy Conversion Congress and Exposition, ECCE’10, September 2010, pp.
1859-1866.
[54] Y. Wang, J. Zhu, Y. Guo, Y. Li, and W. Xu, "Torque Ripples and Estimation Performance of High
Frequency Signal Injection based Sensorless PMSM Drive Strategies", IEEE Energy Conversion
Congress and Exposition, ECCE’10, September 2010, pp. 1699-1706.
[55] Z. Anping, and W. Jian, "Observation Method for PMSM Rotor Position Based on High Frequency
Signal Injection", in Conf. Rec., IEEE-ICECE, June 2010, pp. 3933-3936.
[56] D. Basic, F. Malrait, and P. Rouchon, "Initial Rotor Position Detection in PMSM based on Low
Frequency Harmonic Current Injection", in IEEE Conf. Rec., 14th International Power Electronics and
Motion Control Conference EPE-PEMC, September 2010, pp. 1-7.
[57] W. Staffler, and M. Schrö "Extended mechanical observer structure with load torque estimation for
dl,
sensorless dynamic control of permanent magnet synchronous machines", in IEEE Conf. Rec., 14th
International Power Electronics and Motion Control Conference EPE-PEMC, September 2010, pp. 18-
22.
[58] F. De Belie, P. Sergeant, and J. A. Melkebeek, "A Sensorless Drive by Applying Test Pulses Without
Affecting the Average-Current Samples", IEEE Transactions on Power Electronics, Vol. 25, No. 4,
April 2010, pp. 875-888.
[59] H. Chaoui, W. Gueaieb, and M. C.E. Yagoub, "Neural Network Based Speed Observer for Interior
Permanent Magnet Synchronous Motor Drives", in Conf. Rec., IEEE-EPEC, October 2009, pp. 1-6.
[60] J. L. F. Daya, V. Subbiah, "Robust Control of Sensorless Permanent Magnet Synchronous Motor
Drive using Fuzzy Logic", in Conf. Rec., IEEE-ICACC, June 2010, pp. 14-18.
[61] H. Chaoui, and P. Sicard, "Sensorless Neural Network Speed Control of Permanent Magnet
Synchronous Machines with Nonlinear Stribeck Friction", IEEE/ASME International Conference on
Advanced Intelligent Mechatronics (AIM), July 2010, pp. 926-931.
[62] A. Accetta, M. Cirrincione, and M. Pucci, "Sensorless Control of PMSM by a Linear Neural
Network: TLS EXIN Neuron", Proc. of the 36th Annual Conference of the IEEE-IECON, November
2010, pp. 974-978.
[63] C. B. Butt, M. A. Hoque, and M. A. Rahman, "Simplified Fuzzy-Logic-Based MTPA Speed Control
of IPMSM Drive", IEEE Transactions on Industry Applications, Vol. 40, No. 6, November/December
2004, pp. 1529-1535.
[64] K. K. Halder, N. K. Roy, and B. C. Ghosh, "A High Performance Position Sensorless Surface
Permanent Magnet Synchronous Motor Drive Based on Flux Angle", in Conf. Rec., IEEE-ICECE,
December 2010, pp. 78-81.
65
23. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 2, No 5, 2011
[65] M. Hinkkanen, T. Tuovinen, L. Harnefors, and J. Luomi, "Analysis and Design of a Position
Observer with Stator-Resistance Adaptation for PMSM Drives", in Conf. Rec., IEEE-ICEM, September
2010, pp. 1-6.
[66] S. Koonlaboon, and S. Sangwongwanich, "Sensorless Control of Interior Permanent Magnet
Synchronous Motors Based on A Fictitious Permanent Magnet Flux Model", in Conf. Rec., IEEE-
IAS'05, Vol. 1, October 2005, pp. 311-318.
[67] Y. Inoue, Y. Kawaguchi, S. Morimoto, and M. Sanada, "Performance Improvement of Sensorless
IPMSM Drives in a Low-Speed Region Using Online Parameter Identification", IEEE Transactions on
Industry Applications, Vol. 47, No. 2, March/April 2011, pp. 798-804.
[68] M. Hinkkanen, T. Tuovinen, L. Harnefors, and J. Luomi, "A Reduced-Order Position Observer With
Stator-Resistance Adaptation for PMSM Drives", in Proc. of the IEEE-ISIE Conf., July 2010, pp. 3071-
3076.
[69] Magnus Jansson, Lennart Harnefors, Oskar Wallmark, and Mats Leksell, "Synchronization at Startup
and Stable Rotation Reversal of Sensorless Nonsalient PMSM Drives", IEEE Transactions on Industrial
Electronics, Vol. 53, No. 2, April 2006, pp. 379-387.
66