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Vector control is a more advanced and precise method of controlling AC induction motors compared to scalar control. It involves transforming the motor currents and voltages into a rotating reference frame to obtain decoupled control similar to a DC motor. This allows for independent control of flux and torque for faster dynamic response and better performance than scalar control. The basic implementation of vector control uses Clarke and Park transformations to convert between stationary and rotating reference frames in the controller. It provides DC motor-like precision in speed and torque control of induction motors.

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Choice of converter configuration

Choice of converter configuration

Automatic load frequency control

Automatic load frequency control

Updated field oriented control of induction motor.pptx

Updated field oriented control of induction motor.pptx

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Choice of converter configuration

The document discusses converter configurations and analyzes a 12 pulse converter. It begins by explaining pulse number and valve/switch types in converters. It then discusses how converter configuration is selected based on pulse number to maximize valve and transformer utilization. It provides equations for peak inverse voltage, utilization factor, and transformer rating calculations. Finally, it analyzes a 12 pulse converter, explaining how two transformers connected in star-star and star-delta configurations produce 12 pulses of output with each pulse having a 30 degree duration.

Automatic load frequency control

This topic belongs to Power System Operation and Control. It will help to all electrical engineering students as well as faculties.

Updated field oriented control of induction motor.pptx

It is a simulation work project done on a 5hp,440V/5A and 1440rpm Induction motor.It explains the control of induction motor using matlab-simulink algorithm by PI control as well as Fuzzy logic control.

Rotor Resistance Control and Slip Power Control using Chopper

Rotor Resistance Control and Slip Power Control using Chopper
Closed Loop Control of Induction Motor

Swing equation

The document discusses swing equation, which is used to model rotor dynamics in power systems. It defines swing equation as a second order differential equation that relates the change in rotor angle over time to the difference between mechanical and electrical power inputs. The document outlines the derivation of swing equation from the torque-speed relationship of a synchronous generator. It also discusses swing curves, which plot electrical power output versus rotor angle, and the equal area criteria method for assessing transient stability using swing curve plots.

Synchronous motor drive

The document discusses synchronous motors used to drive textile and paper mill equipment. It describes different types of synchronous motors including wound field, permanent magnet, synchronous reluctance, and hysteresis motors. It explains that synchronous motors can operate in an adjustable frequency control mode called self-controlled mode, where the supply frequency is controlled by an inverter receiving signals from a frequency controlled oscillator. In this mode, the motor exhibits constant torque behavior up to base speed and flux weakening at higher speeds, with fast transient response similar to a DC motor but smaller rotor inertia.

Permanent magnet motor drives.pptx

The document discusses several types of permanent magnet (PM) motors, including brushed DC motors, brushless DC motors, AC synchronous motors, PM stepper motors, switched reluctance motors, and linear PM motors. It notes the advantages and applications of each type. The document then focuses on brushless DC (BLDC) motors and permanent magnet synchronous motors (PMSM), comparing their drive configurations, which involve using an inverter and electronic commutation to control motor speed and torque based on position sensor feedback. It also discusses speed and torque control methods for BLDC and PMSM motors.

Unit 2.Converter and Chopper fed Dc drives

This document discusses different types of DC drives fed by converters or choppers. It describes phase controlled rectifier fed DC drives which can be single or three phase. It also discusses various types of chopper fed DC drives including one, two and four quadrant drives. Specific circuits are presented for single phase half wave and fully controlled rectifiers used in DC drives. Operation of two and four quadrant choppers for motoring, regenerative braking and reverse braking modes are also covered.

Comparision of svc and statcom

The document compares the characteristics of STATCOM and SVC devices. It discusses their V-I and V-Q characteristics, transient stability, response time (STATCOM is faster at 200-300 microseconds vs SVC at 2.5-5 milliseconds), capability to exchange real power (only STATCOM can do this), operation with unbalanced systems, loss characteristics, and physical size (STATCOM is 30-40% smaller without need for large capacitor and reactor banks).

Facts controller

This document discusses Flexible AC Transmission Systems (FACTS) controllers. It defines FACTS controllers as power electronic devices that control parameters of AC transmission systems. The document describes several types of FACTS controllers including STATCOM, SVC, TCSC, SSSC, and UPFC. It explains how each type of controller works and its benefits such as increasing power transfer capability and network reliability.

Voltage source Converters as a building block of HVDC and FACTS

This document discusses voltage source converters (VSCs) and their use in HVDC and FACTS systems. It provides background on VSCs and how they allow independent control of real and reactive power. The first HVDC transmission using VSC converters took place in 1997 in Sweden. VSCs generate AC voltage from DC and can control output voltage magnitude, phase, and frequency. When used for HVDC, multiple VSCs can be connected in series to reduce harmonics. FACTS devices using VSCs, such as STATCOMs, can control power flow and provide voltage regulation on transmission lines.

Control of electric drive

- Electrical drives enable control of motors in all aspects including starting, speed control, and braking. Control is necessary as these operations involve large transient changes in voltage, current, etc. that could damage the motor.
- Electrical drives operate in three modes: steady-state, acceleration, and deceleration. Closed-loop control is used for protection, fast response, and accuracy. Common closed-loop controls include current limiting, torque control, and speed control using feedback loops. Speed control is widely used and can involve inner current and outer speed loops.

Facts devices

The concept of FACTS (Flexible Alternating Current Transmission System) refers to a family of power electronics-based devices able to enhance AC system controllability and stability and to increase power transfer capability.

Motor drives

This document discusses DC motor drives. It provides an overview of DC drives, including their applications, advantages, and types. It describes the basic characteristics and operating modes of shunt, series, and separately excited DC motors, including motoring, regenerative braking, dynamic braking, and plugging modes. It also discusses four quadrant operation of DC motors.

Series & shunt compensation and FACTs Devices

Series compensation is used to improve the performance of extra high voltage transmission lines by connecting capacitors in series with the line. It allows for increased transmission capacity and improved system stability by reducing the phase angle between sending and receiving end voltages for the same power transfer. Shunt compensation controls the receiving end voltage by connecting shunt capacitors or reactors to meet reactive power demand and prevent voltage drops or rises. Flexible AC transmission systems use high-speed thyristors to switch transmission line components like capacitors and reactors to control parameters like voltages and reactances to optimize power transfer.

Firing angle control

This document discusses different types of firing angle control schemes for HVDC converters, including individual phase control (IPC) and equidistant phase control (EPC). IPC allows independent control of each phase's firing angle based on commutation voltages. EPC generates firing angles at equal intervals through a ring counter. Higher-level controllers are also discussed that can control DC power modulation for frequency regulation, emergency control, reactive power control, and damping of sub-synchronous oscillations. Voltage source converter control is mentioned, where the modulation index and phase angle are used to regulate active and reactive power flow.

Fixed and variable speed turbine

Fixed speed wind turbines always spin at the same speed regardless of wind speed, so their aerodynamic performance is only optimal at one wind speed. They use an induction generator directly connected to the power grid via a transformer to maintain a fixed frequency. Variable speed wind turbines allow the rotor speed to vary proportionally to wind speed between cut-in and rated speeds to maintain optimal aerodynamic performance through constant tip-speed ratio, and actively control torque above rated wind speed.

Load flow studies 19

Power System Analysis:
Load flow studies:Gauss siedel,newton Raphson,Fast decoupled,dc power flow equations,problems

PMSM

The presentation contains the details about types of PMSM,Speed control of PMSM and comparison of PMSM drives

Planning and modern trends in hvdc

The document discusses planning for HVDC transmission and modern trends in HVDC technology. When planning HVDC transmission, the key factors to consider are cost, technical performance, and reliability. Modern trends aim to reduce converter station costs while improving reliability and performance. This includes advances in power semiconductors, converter control technology, development of DC breakers, conversion of existing AC lines, and operation with weak AC systems. Emerging technologies discussed are active DC filters, capacitor commutated converters, and ultra-high voltage DC transmission.

Choice of converter configuration

Choice of converter configuration

Automatic load frequency control

Automatic load frequency control

Updated field oriented control of induction motor.pptx

Updated field oriented control of induction motor.pptx

Rotor Resistance Control and Slip Power Control using Chopper

Rotor Resistance Control and Slip Power Control using Chopper

Swing equation

Swing equation

Synchronous motor drive

Synchronous motor drive

Permanent magnet motor drives.pptx

Permanent magnet motor drives.pptx

Unit 2.Converter and Chopper fed Dc drives

Unit 2.Converter and Chopper fed Dc drives

Comparision of svc and statcom

Comparision of svc and statcom

Facts controller

Facts controller

Voltage source Converters as a building block of HVDC and FACTS

Voltage source Converters as a building block of HVDC and FACTS

Control of electric drive

Control of electric drive

Facts devices

Facts devices

Motor drives

Motor drives

Series & shunt compensation and FACTs Devices

Series & shunt compensation and FACTs Devices

Firing angle control

Firing angle control

Fixed and variable speed turbine

Fixed and variable speed turbine

Load flow studies 19

Load flow studies 19

PMSM

PMSM

Planning and modern trends in hvdc

Planning and modern trends in hvdc

Facts devices mayank

The document presents information on STATCOM (Static Synchronous Compensator), a type of FACTS (Flexible AC Transmission System) device. It begins with an objective to improve reliability, flexibility, response and accuracy in power systems. It then introduces STATCOM as a shunt controller that generates or absorbs reactive power without energy storage by circulating current among AC system phases using a voltage source converter. The basic principle, components, operation and control of STATCOM are described. Comparison is made between STATCOM and synchronous condenser, with advantages of STATCOM listed. The conclusion states that STATCOM allows a power system to be made more reliable, flexible, fast and accurate.

Vector control of induction motor

Vector control of AC induction motors provides superior dynamic performance compared to scalar control by decoupling torque and flux control. Vector control represents the stator currents as direct and quadrature components (Ids and Iqs) that independently control flux and torque. This allows precise and independent control of torque and flux to eliminate oscillations for applications requiring high performance like robotics. Vector control implementations determine the orientation of Ids and Iqs either directly by measuring airgap flux or indirectly by measuring slip speed to achieve independent control of the current components.

14. a variable speed, sensorless, induction motor drive

The document presents a new sensorless control strategy for a three-phase induction motor drive using only DC link current measurements. The strategy estimates motor speed and torque through signal reconstruction rather than direct sensor readings. It includes independent speed and torque control loops as well as current regulation. Simulation results on a 2.2 kW induction motor show fast dynamic response and good agreement between actual and estimated torque and speed values. The proposed drive requires only one current sensor in the DC link, making it suitable for low-cost sensorless motor applications.

IRJET- Vector Control of Three Phase Induction Motor

This document discusses vector control of a three-phase induction motor. Vector control, also called field-oriented control, allows independent control of torque and flux in induction motors, similar to DC motors. The document describes:
1) How vector control works by transforming stator currents into orthogonal d-q components representing flux and torque.
2) The principle of field-oriented control which locks the d-q reference frame to the rotor flux vector for decoupled control of flux and torque.
3) The simulation model built in MATLAB/Simulink to test vector control, including blocks for Clarke/Park transformations, current control, and a PI speed controller.

Performance Analysis Of Induction Motor For Voltage Mode And Current Mode Con...

This document discusses the performance analysis of an induction motor using voltage mode and current mode control. It compares hysteresis current control and space vector pulse width modulation (SVPWM). Hysteresis control directly limits current peaks but SVPWM provides higher voltage output and lower harmonic distortion. The document simulates an induction motor drive using SVPWM-based hysteresis current control in MATLAB. Key steps include Clark transformation to generate reference signals, switching between active and zero vectors to synthesize the reference signal, and using hysteresis control to generate PWM signals from current errors. Simulation results show the SVPWM controller provides good speed and current regulation for the induction motor.

NEURAL NETWORK BASED VECTOR CONTROL OF INDUCTION MOTOR

Stator current drift compensation of induction motor based on RBF neural network is proposed here. In vector control of induction motor decoupling of speed and rotor flux equations and their simultaneous control are used to achieve the highest efficiency and fast dynamic
performance. The highest efficiency is reached when the proper flux is selected and as a result of dynamic decoupling of speed and rotor flux equations, the rotor flux can be modified to achieve the highest efficiency and make the speed be at its desired value. The precise control of these changes can also be done using radial basis function neural network (RBFNN). Once
neural network gets trained then it is able to differentiate between normal and fault conditions and therefore acts in accordance to the change that could bring back the system to normal condition. Here, neural network is used to compute the appropriate set of voltage and frequency
to achieve the maximum efficiency for any value of operating torque and motor speed.

NEURAL NETWORK BASED VECTOR CONTROL OF INDUCTION MOTOR

Stator current drift compensation of induction motor based on RBF neural network is proposed here. In vector control of induction motor decoupling of speed and rotor flux equations and their simultaneous control are used to achieve the highest efficiency and fast dynamic performance. The highest efficiency is reached when the proper flux is selected and as a result
of dynamic decoupling of speed and rotor flux equations, the rotor flux can be modified to achieve the highest efficiency and make the speed be at its desired value. The precise control of
these changes can also be done using radial basis function neural network (RBFNN). Once neural network gets trained then it is able to differentiate between normal and fault conditions
and therefore acts in accordance to the change that could bring back the system to normal condition. Here, neural network is used to compute the appropriate set of voltage and frequency
to achieve the maximum efficiency for any value of operating torque and motor speed.

Neural network based vector control of induction motor

1) The document presents a study on using a radial basis function neural network (RBFNN) to compensate for drift in the stator currents of an induction motor under vector control. Stator current data with implemented errors was collected to train the RBFNN.
2) An RBFNN with 3 input, 125 hidden, and 3 output nodes trained on 960 data points achieved a root mean square error of 0.34525. When tested, the network was able to restore stator currents close to their original values, validating that it can compensate for drift.
3) Using an RBFNN with k-means clustering to select hidden nodes was able to learn the compensation behavior accurately from data and generalize

Vector control of induction motor

This document provides an overview of vector control of AC induction motors compared to scalar control. Vector control decouples the torque and flux produced by the motor, allowing for more precise independent control. It does this by controlling the direct current (Id) that produces flux and quadrature current (Iq) that produces torque. There are two approaches to vector control - direct field oriented control that directly measures the rotor angle and indirect field oriented control that indirectly measures it using slip speed. Key benefits of vector control are fast transient response since torque can be controlled without affecting flux, and ability to control speed in all four quadrants.

Performance of PWM Rectifier with Different Types of Load

The paper presents the decoupled vector control of the PWM rectifier with the nonlinear DC-link voltage regulation and the load compensating feed forward. The concept of the proposed control system is based on Voltage Oriented Control with Space-Vector Pulse Width Modulation (SV-PWM). For the high-performance operation of the PWM rectifier and the satisfactory current tracing the decoupled current control has been introduced. The performance of the linear PI controller of the DC-link voltage is strictly dependent on its settings and it may introduce a disadvantageous voltage overshoot under a heavy load impact. In order to improve the transient response of the DC-link voltage control loop a load compensation has been proposed. The different approach to the control of the DC-link voltage based on the regulation of the square power of the DC voltage has been introduced.

78201910

1) The document describes a system for controlling the speed of a CUK converter-fed BLDC motor using a PI controller.
2) A CUK converter is used to provide power to the BLDC motor and PI control is applied to regulate the output voltage of the CUK converter in order to control the motor speed.
3) Simulation results show that the proposed PI controller is able to effectively control the motor speed while maintaining low current ripple and reducing torque ripples.

F05613947

This document presents a sensor-less speed control method for induction motors using alpha-cut fuzzy logic field oriented control (FOC). It develops a non-linear induction motor model that accounts for errors in flux estimation. FOC is used to decouple the current components for flux generation and torque generation. Clarke and Park transformations are applied to control the d-q axis currents for flux and torque regulation using PI controllers. Simulations show the motor speed closely follows the reference speed even under load, maintaining stability. The stator current and electromagnetic torque responses indicate the control system effectively regulates load current and torque.

H04945260

- The document describes a unified power flow controller (UPFC) which consists of two voltage source converters connected respectively in series and shunt with a transmission line, with a common DC link.
- It proposes modeling the UPFC using a discrete simulator in MATLAB with 12-pulse converters to reduce voltage harmonics, and controlling the series and shunt converters separately while coordinating them.
- Simulation results showed the UPFC model reflected static and dynamic characteristics, and harmonics analysis was performed on the output during different system conditions including faults.

VSC BASED HVDC SYTEM DESIGN AND PROTECTION AGAINST OVER VOLTAGES

High Voltage Direct Current system based on voltage source converter (VSC-HVDC) is becoming
more effective solution for offshore wind plants and supplying power to remote regions. In this paper, the
control of a VSC-based HVDC system (VSC-HVDC) is described. Based on this control strategy, appropriate
controllers utilizing PI controllers are designed to control the active and reactive power at each end station.The
operation performance of a voltage source converter (VSC) based HVDC (VSC-HVDC system) system is
explained under some characteristic faulted conditions with and without protection measures. A protection
strategy is proposed to enhance the continuous operation performance of the VSC-HVDC system. The strategy
utilizes a voltage chopper to suppress over-voltages on the DC side of the VSC. Digital simulation is done to
verify the validity of the proposed control strategy and protection strategy

International Journal of Engineering Research and Development (IJERD)

journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal

Induction motor harmonic reduction using space vector modulation algorithm

The vector control was proposed as an alternative to the scalar control for AC machines control. Vector control provide high operation performance in steady state and transient operation. However, the variable switching frequency of vector control causes high flux and torque ripples which lead to an acoustical noise and degrade the performance of the control scheme. The insertion of the space vector modulation was a very useful solution to reduce the high ripples level inspite of its complexity. Numerical simulation results obtained in MATLAB/Simulink show the good dynamic performance of the proposed vector control technique and the effectiveness of the proposed sensorless strategy in the presence of the sudden load torque basing on the integral backstepping approach capabilities on instant perturbation rejection.
Keywords

PWM

The document discusses pulse width modulation (PWM) variable speed drives that are increasingly used in industrial applications. It describes how PWM is used to generate variable voltage and frequency for AC drives from a three-phase voltage source inverter. Space vector PWM (SVPWM) is highlighted as it provides superior harmonic quality and larger modulation range compared to sinusoidal PWM. SVPWM represents the inverter states as voltage space vectors to calculate duty cycles for adjacent vectors and zero vectors to synthesize the desired output voltage vector. The document outlines the theory of SVPWM and compares different sequencing methods. It also discusses simulations and advantages of PWM including proportional average value, fast switching, noise resistance and less heat.

Study of Vector Control Algorithm and Inverter design for BLDC Motor, V/f con...

This document summarizes a study on vector control algorithms and inverter design for BLDC motors. It discusses the objectives of studying BLDC motor operation, different control algorithms including vector control, and inverter design. It also covers V/F control of induction motors. Key topics covered include Clarke/Park transformations, sensorless control, inverter topologies, and a comparison of vector and V/F control techniques. The document is authored by engineering students and provides an overview of various motor control concepts and algorithms.

K10913 dhirendra gocher me 6th sem

The document discusses DC motor control using Simscape. It describes using various Simscape blocks like a DC voltage source, current sensor, rotational electromechanical converter and rotational damper to model a DC motor. It also uses a rotational motion sensor to measure the motor shaft position and velocity. The model shows good speed and position control of the motor under varying load conditions during simulation.

Control Strategy for PWM Voltage Source Converter Using Fuzzy Logic for Adjus...

Control Strategy for PWM Voltage Source Converter Using Fuzzy Logic for Adjus...International Journal of Power Electronics and Drive Systems

This document describes a control strategy for a PWM voltage source converter (PWM-VSC) using fuzzy logic to provide variable DC voltage for controlling the speed of a DC motor. A fuzzy logic controller is proposed to minimize errors in the DC voltage and stabilize it by regulating the amplitude of the network current. Simulation results show the fuzzy logic controller produces a stable DC voltage without overshoot to drive the DC motor, with less than 5% total harmonic distortion in the network current and a power factor near unity. The DC motor speed is also stable without overshoot in response to variations in the controlled DC voltage.Facts devices mayank

Facts devices mayank

Vector control of induction motor

Vector control of induction motor

14. a variable speed, sensorless, induction motor drive

14. a variable speed, sensorless, induction motor drive

IRJET- Vector Control of Three Phase Induction Motor

IRJET- Vector Control of Three Phase Induction Motor

Performance Analysis Of Induction Motor For Voltage Mode And Current Mode Con...

Performance Analysis Of Induction Motor For Voltage Mode And Current Mode Con...

NEURAL NETWORK BASED VECTOR CONTROL OF INDUCTION MOTOR

NEURAL NETWORK BASED VECTOR CONTROL OF INDUCTION MOTOR

NEURAL NETWORK BASED VECTOR CONTROL OF INDUCTION MOTOR

NEURAL NETWORK BASED VECTOR CONTROL OF INDUCTION MOTOR

Neural network based vector control of induction motor

Neural network based vector control of induction motor

Vector control of induction motor

Vector control of induction motor

Performance of PWM Rectifier with Different Types of Load

Performance of PWM Rectifier with Different Types of Load

78201910

78201910

F05613947

F05613947

H04945260

H04945260

VSC BASED HVDC SYTEM DESIGN AND PROTECTION AGAINST OVER VOLTAGES

VSC BASED HVDC SYTEM DESIGN AND PROTECTION AGAINST OVER VOLTAGES

International Journal of Engineering Research and Development (IJERD)

International Journal of Engineering Research and Development (IJERD)

Induction motor harmonic reduction using space vector modulation algorithm

Induction motor harmonic reduction using space vector modulation algorithm

PWM

PWM

Study of Vector Control Algorithm and Inverter design for BLDC Motor, V/f con...

Study of Vector Control Algorithm and Inverter design for BLDC Motor, V/f con...

K10913 dhirendra gocher me 6th sem

K10913 dhirendra gocher me 6th sem

Control Strategy for PWM Voltage Source Converter Using Fuzzy Logic for Adjus...

Control Strategy for PWM Voltage Source Converter Using Fuzzy Logic for Adjus...

- 1. Vector Control of Induction Motors Pranjal Barman Research Scholar Department of Electronics and Communication Engineering Tezpur University
- 2. Two control approaches of AC drives Scalar Control : Scalar control is the term used to describe a simpler form of AC motor control. Controlled by the adjustable magnitude of stator voltages and frequency in such a way that the air gap flux is always maintained at the desired value at the steady-state Vector Control : The machine current and voltage space vectors, the transformation of a 3 phase speed and time dependent system into a two co- ordinate time invariant system and effective PWM pattern generation
- 3. Scalar Control vs Vector Control Scalar Simpler form of motor control Good steady state performance Poor dynamic response Low performance drives Higher power dissipation Vector Complex mathematical model Precise control of ac motors Excellent dynamic response High performance drives Low power dissipation
- 4. Analogy with DC motor control There is a close parallel between torque control of a DC motor and vector control of an AC motor. The DC motor field flux produced by field current is orthogonal to the armature flux produced by the armature current . Because the vectors are orthogonal, they are decoupled, i.e. the field current only controls the field flux and the armature current only controls the armature flux.
- 5. Analogy with DC motor control DC motor-like performance can be achieved with an induction motor if the motor control is considered in the synchronously rotating reference frame (de-qe) where the sinusoidal variables appear as dc quantities in steady state. With vector control: ids (induction motor) If (dc motor) iqs (induction motor) Ia (dc motor)
- 6. Principles of Vector Control The basic conceptual implementation of vector control is illustrated in the below block diagram:
- 7. Principles of Vector Control The motor phase currents, ia, ib and ic are converted to ids s and iqs s in the stationary reference frame. These are then converted to the synchronously rotating reference frame d-q currents, ids and iqs. In the controller two inverse transforms are performed: 1) From the synchronous d-q to the stationary d-q reference frame; 2) From d*-q* to a*, b*, c*.
- 8. Time invariant coordinate transform (a,b,c)⇒(α,β) (the Clarke transformation) which outputs a two co-ordinate time variant system (α,β)⇒(d,q) (the Park transformation) which outputs a two co-ordinate time invariant system
- 11. Inverse Park transformation Voltage transformation that modifies the voltages in d,q rotating reference frame in a two phase orthogonal system
- 12. Vector control types There are two approaches to vector control: 1) Direct field oriented current control - here the rotation angle of the iqs e vector with respect to the stator flux is being directly determined (e.g. by measuring air gap flux) 2) Indirect field oriented current control - here the rotor angle is being measured indirectly, such as by measuring slip speed
- 13. Field Orientation Control • In direct FOC the field angle is calculated by using terminal voltages and current or Hall sensors or flux sense windings.
- 14. Salient Features of Vector Control Transient response will be fast because torque control by iqs does not affect flux. Vector control allows for speed control in all four quadrants (without additional control elements Automatically limits operation to the stable region.
- 15. Space Vector PWM Inverter switches are driven with two complementary pulsed signals, providing care is taken to ensure that there is no overlap in the power switch transitions. SVPWM is a technique for generating such pulsed signals Minimizes the harmonic contents
- 16. These eight switch combinations determine eight phase voltage configurations The vectors divide the plan into six sectors The binary representations of two adjacent basic vectors differ in only one bit SVPWM, vectors and sectors
- 17. Conclusion Vector control/FOC used in high performance drives where oscillations in air gap flux linkages are intolerable, e.g. robotic actuators, centrifuges, servos, etc. Field Orientated Controlled AC machines thus obtain every DC machine advantage Since high computational power silicon devices, came to market it has been possible to realize far more precise digital vector control algorithms More computational effort and high speed processors are suitable
- 18. References 1. “Field Orientated Control of 3-Phase AC-Motors”; Literature Number: BPRA073,Texas Instruments Europe, February 1998 2. “Comparison of scalar and vector control strategies of Induction Motors”; G.Kohlrusz, D.Fodor 3. “Scalar (V/f) Control of 3-Phase Induction Motors”; Application Report SPRABQ8–July 2013
- 19. Thank You