Brushless DC (BLDC) motor drives are becoming more popular in industrial and traction applications. Hence the control of BLDC motor in four quadrants is very vital. The flexibility of the drive system is increased using digital controller. In this paper the PWM signals for driving the power inverter bridge for BLDC motor have been successfully implemented using a dsPIC controller and the motor can be controlled in all the four quadrants without any loss of power .Energy is conserved during regenerative braking period. The digital controller dsPIC, is advantageous over other controller, as it combines the calculation capability of digital signal processor and controlling capability of PIC microcontroller to achieve a precise control. Simulation of the proposed model is done by using MATLAB/Simulink.
This project is designed to control the speed of a single-phase induction motor by using operating knob, which is commonly used in home automation applications. The main advantage of these motors is their ability to operate from a single-phase power supply
This project is designed to control the speed of a single-phase induction motor by using operating knob, which is commonly used in home automation applications. The main advantage of these motors is their ability to operate from a single-phase power supply
Er.Amit Chaurasiya studies at Azad Technical Campus Lucknow.All slide make very clear and easily understood suitable for Electrical Engineering students. I hope you will easily understand.
A reluctance motor is a type of electric motor that induces non-permanent magnetic poles on the ferromagnetic rotor. The rotor does not have any windings. It generates torque through magnetic reluctance.
Reluctance motor sub types include synchronous, variable, switched and variable stepping.
Reluctance motors can deliver high power density at low cost, making them attractive for many applications. Disadvantages include high torque ripple (the difference between maximum and minimum torque during one revolution) when operated at low speed, and noise due to torque ripple.
Inter Connected Power System(Turbine Speed Governing Mechanism)Raviraj solanki
Inter Connected Power SystemTOPIC : Turbine Speed Governing Mechanism
Introduction
Turbine Speed Governing Mechanism
Mathematical Modeling
Adjustment Of Governor Characteristics
The speed governing system consists of the following parts .
Speed governor
Linkage mechanism
Hydraulic amplifier
Speed changer
Effect of non sinusoidal waveform of a.c. machine performancevishalgohel12195
Effect of Non sinusoidal waveform of A.C. Machine performance
Nonsinusoidal Waveforms
Key Similarities and Differences between Sinusoidal and Nonsinusoidal Waveforms
Effect of harmonics in motor drives
Square wave inverter with 180° mode
Effect of leakage reactance on the harmonic content of current
Parasitic torques due to non-sinusoidal voltages
This predefined speed control of BLDC motor runs a motor at user desired speed by using EEPROM for storing speed. It is an effective speed control method.
The main objective of this project is controlling speed of BLDC motors with the help of microcontroller. To make the industry automation the equipment and machineries should be controlled automatically. So control of the machineries which involving this motor can be done accurately. It displays its speed using an IR method of speed sensor mechanism.
Torque Production & Control of Speed in Synchronous Motor.
Speed of synchronous motors can be controlled using two methods called open loop and close loop control.
Open loop contol is the simplest scalar control method where motor speed is controlled by independent frequency control of the converter.
In case of close loop self control mode, instead of controlling the inverter frequency independentaly, the frequency and the phase of the output waveform are controlled by an absolute position encoder mounted on the machine shaft giving an account of position of the rotor.
Electrical drives are integral part of industrial and automation processes, particularly where precise control of speed of the motor is the prime requirement. In addition, all modern electric trains or locomotive systems have been powered by electrical drives. Robotics is another major area where adjustable speed drives offer precise speed and position control.
Brushles DC motor are one type of motors that are rapidly gaining the popularity and are penetrating in industrial applications, home appliances, automotive, consumer, medical etc. Because of there many advantages such as high efficiency ,silent operation, compact form ,reliability, low maintenance (due to the absence of brushess), long operating life, high speed ranges etc. for the proper commution of current in inverter the rotar position information is necessary, this information is usually provided by the mechanical position sensors mounted within the motor. however it is well known that these position sensors have many drawbacks therefore a sensor less control of BLDC motor is developed which eliminates the sensing equipment ,reduces the cost of motor and increases the reliability of the BLDC motor. In this paper the position information is obtained from the zero crossing detection of the back EMF which is also called as the terminal voltage sensing method which is the simplest ,method of detecting the back EMF zero crossing ,here the motor voltages are sensed and give to the lowpass filter whose output is give to the ZCD which determines the zero crossing of the back EMF waveform and ZCD generates the signal required for the controller to provide the pulses for the inverter operation the controller used is a high performance controller(DSPic30F4011) which as both the features of microcontroller and digital signal processor .The complete model is simulated in MATLAB/SIMULINK software. the proposed hardware and simulation program are found to be efficient and the results are promising
This project is used to control the speed of brushless DC motor by using arduino development board with rpm display and pulse width modulation. It can be used in different industrial applications.
Er.Amit Chaurasiya studies at Azad Technical Campus Lucknow.All slide make very clear and easily understood suitable for Electrical Engineering students. I hope you will easily understand.
A reluctance motor is a type of electric motor that induces non-permanent magnetic poles on the ferromagnetic rotor. The rotor does not have any windings. It generates torque through magnetic reluctance.
Reluctance motor sub types include synchronous, variable, switched and variable stepping.
Reluctance motors can deliver high power density at low cost, making them attractive for many applications. Disadvantages include high torque ripple (the difference between maximum and minimum torque during one revolution) when operated at low speed, and noise due to torque ripple.
Inter Connected Power System(Turbine Speed Governing Mechanism)Raviraj solanki
Inter Connected Power SystemTOPIC : Turbine Speed Governing Mechanism
Introduction
Turbine Speed Governing Mechanism
Mathematical Modeling
Adjustment Of Governor Characteristics
The speed governing system consists of the following parts .
Speed governor
Linkage mechanism
Hydraulic amplifier
Speed changer
Effect of non sinusoidal waveform of a.c. machine performancevishalgohel12195
Effect of Non sinusoidal waveform of A.C. Machine performance
Nonsinusoidal Waveforms
Key Similarities and Differences between Sinusoidal and Nonsinusoidal Waveforms
Effect of harmonics in motor drives
Square wave inverter with 180° mode
Effect of leakage reactance on the harmonic content of current
Parasitic torques due to non-sinusoidal voltages
This predefined speed control of BLDC motor runs a motor at user desired speed by using EEPROM for storing speed. It is an effective speed control method.
The main objective of this project is controlling speed of BLDC motors with the help of microcontroller. To make the industry automation the equipment and machineries should be controlled automatically. So control of the machineries which involving this motor can be done accurately. It displays its speed using an IR method of speed sensor mechanism.
Torque Production & Control of Speed in Synchronous Motor.
Speed of synchronous motors can be controlled using two methods called open loop and close loop control.
Open loop contol is the simplest scalar control method where motor speed is controlled by independent frequency control of the converter.
In case of close loop self control mode, instead of controlling the inverter frequency independentaly, the frequency and the phase of the output waveform are controlled by an absolute position encoder mounted on the machine shaft giving an account of position of the rotor.
Electrical drives are integral part of industrial and automation processes, particularly where precise control of speed of the motor is the prime requirement. In addition, all modern electric trains or locomotive systems have been powered by electrical drives. Robotics is another major area where adjustable speed drives offer precise speed and position control.
Brushles DC motor are one type of motors that are rapidly gaining the popularity and are penetrating in industrial applications, home appliances, automotive, consumer, medical etc. Because of there many advantages such as high efficiency ,silent operation, compact form ,reliability, low maintenance (due to the absence of brushess), long operating life, high speed ranges etc. for the proper commution of current in inverter the rotar position information is necessary, this information is usually provided by the mechanical position sensors mounted within the motor. however it is well known that these position sensors have many drawbacks therefore a sensor less control of BLDC motor is developed which eliminates the sensing equipment ,reduces the cost of motor and increases the reliability of the BLDC motor. In this paper the position information is obtained from the zero crossing detection of the back EMF which is also called as the terminal voltage sensing method which is the simplest ,method of detecting the back EMF zero crossing ,here the motor voltages are sensed and give to the lowpass filter whose output is give to the ZCD which determines the zero crossing of the back EMF waveform and ZCD generates the signal required for the controller to provide the pulses for the inverter operation the controller used is a high performance controller(DSPic30F4011) which as both the features of microcontroller and digital signal processor .The complete model is simulated in MATLAB/SIMULINK software. the proposed hardware and simulation program are found to be efficient and the results are promising
This project is used to control the speed of brushless DC motor by using arduino development board with rpm display and pulse width modulation. It can be used in different industrial applications.
Traction Application Insight by Jaguar Land RoverAutomotive IQ
For today’s efforts to drive eMotor Innovation, the reduction of cost and weight of permanent magnets is essential! But what are the options? Is moving away from the Permanent Magnet Synchronous Motor the right thing to do? Dr. Alex Michaelides, Technical Specialist - Electrical Machines and Power Electronics at Jaguar Land Rover discusses these questions in the presentation here: http://bit.ly/Presentation-Michaelides
Arm Processor Based Speed Control Of BLDC MotorUday Wankar
The project is designed to control the speed of a DC motor using an ARM series processor. The speed of DC motor is directly proportional to the voltage applied across its terminals. Hence, if voltage across motor terminal is varied, then speed can also be varied. This project uses the above principle to control the speed of the motor by varying the duty cycle of the pulse applied to it (popularly known as PWM control). The project uses input button interfaced to the processor, which are used to control the speed of motor. PWM (Pulse Width Modulation) is generated at the output by the microcontroller as per the program. The program is written in Embedded C. The average voltage given or the average current flowing through the motor will change depending on the duty cycle (ON and OFF time of the pulses), so the speed of the motor will change. A motor driver IC is interfaced to the STM32 board for receiving PWM signals and delivering desired output for speed control of a small DC motor. Further the project can be enhanced by using power electronic devices such as IGBTs to achieve speed control higher capacity industrial motors.
Three-phase ac motors have been the workhorse of industry since the earliest days of electrical engineering. They are reliable, efficient, cost-effective and need little or no maintenance. In addition, ac motors such as induction and reluctance motors need no electrical connection to the rotor, so can easily be made flameproof for use in hazardous environments such as in mines.
In order to provide proper speed control of an ac motor, it is necessary to supply the motor with a three phase supply of which both the voltage and the frequency can be varied. Such a supply will create a variable speed rotating field in the stator that will allow the rotor to rotate at the required speed with low slip. This ac motor drive can efficiently provide full torque from zero speed to full speed, can overspeed if necessary, and can, by changing phase rotation, easily provide bi-directional operation of the motor. A drive with these characteristics is known as a PWM (Pulse Width Modulated) motor drive.
Drives and motors are an integral part of industrial equipment from packaging,robotics, computer numerical control (CNC), machine tools, industrial pumps,and fans. Designing next-generation drive systems to lower operating costs requires complex control algorithms at very low latencies as well as a flexibleplatform to support changing needs and the ability to design multiple-axis systems.
Traditional drive systems based on ASICs, digital signal processors (DSPs), and microcontroller units lack the performance and flexibility to address these needs. Altera’s family of FPGAs provides a scalable platform that can be used to offload control algorithm elements in hardware. You may also integrate the whole drive system with industry-proven processor architectures while supporting multipletypes of encoders and industrial Ethernet protocols. This “drive on a chip” system reduces cost and simplifies development.
Multi-phase Brush-less DC motor And Applications Zain Ul Abideen
The new technology permanent magnet motors have several advantages over the induction motor: most notably, they are smaller and more efficient. Recently permanent magnet BLDC motors and synchronous motors for warship propulsion are under development in Europe and America. Analysis of this paper shows that, applying asymmetric distributed multi 3-phase BLDC motors can simplify the converter system and reduce torque ripples in low speed. In order to optimize motors' structure and their control methods, a mathematical model of those multi-phase BLDC motors is established in this paper. Certain simulation and experiment methods are presented based on the model. As an example, a double three-phase BLDC motor is detailedly analysed by authors, simulation and experiment results are in good agreement, which confirms the validity of the proposed methods.
These slides describe the effect of increasing the phases on a brush-less DC motor.
It also includes why we use Brush-less Motor instead of Brushed DC Motor.
It includes the driver circuitry explanation too.
If you need further help feel free to catch me at
livezaain@yahoo.com
Analysis and control of four quadrant operation of three phase brushless dc (...eSAT Publishing House
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
Fuzzy Logic Controller for Four Quadrant Operation of Three Phase BLDC MotorIJTET Journal
Abstract— Brushless DC (BLDC) motors are one of the electrical drives that are rapidly gaining popularity in industries. In this paper, proposed system gives a three phase Brushless DC (BLDC) in all four quadrant operation by using fuzzy logic controller. The average settling time delay in conventional PI controller drastically overcome by the fuzzy logic controller in order to achieve the constant speed of the motor in any one of the direction respectively. The back EMF is generated during the reverse motoring. In quadrant operation the breaking is applied leads to waste the kinetic energy as heat energy. Utilization of wasted kinetic energy is stored in a battery possible by proposed scheme. The four quadrant operations are Forward Motoring, Forward Braking, Reverse motoring and Reverse Braking. In forward driving the input feed to the BLDC motor up to the set time fastened. Subsequently the Forward Braking is applied then the motor speed reduced to zero. This helps to create a back emf and that is being converted to DC and stored in a battery. Then the Reverse Motoring is applied for rotating the motor at the reverse direction. At last the Reverse Braking is applied it also create the back emf and the converted energy stored in a battery. Rotor position is obtained by the Hall Sensor signal. The system consist of Input source, Fuzzy logic controller, Three phase inverter, Relay, Brushless DC motor (BLDC), Battery, Hall sensor.
Speed Torque Characteristics of BLDC Motor with Load Variationsijtsrd
Nowadays, Brushless DC motors are in high demand due to its high efficiency and other significant features. As there is no use of brushes, this type of motor is having many advantages like high torque to inertia ratio, high speed, and power density and low cost compared to conventional brushed motors. This paper determines speed torque characteristics of brushless dc motor with different load variation by using the proposed method and the developed controller. The variation in motor speed torque characteristics for half load, full load, and overloading condition is analyzed. This research has been conducted to analyze the model and compared with the simulation results which are very useful in studying the performance of motor system. The simulation is carried out in MATLAB Simulink environment. Ishita Gupta | Akash Varshney "Speed-Torque Characteristics of BLDC Motor with Load Variations" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-4 , June 2020, URL: https://www.ijtsrd.com/papers/ijtsrd31197.pdf Paper Url :https://www.ijtsrd.com/engineering/electrical-engineering/31197/speedtorque-characteristics-of-bldc-motor-with-load-variations/ishita-gupta
Closed Loop Speed Control of a BLDC Motor Drive Using Adaptive Fuzzy Tuned PI...IJERA Editor
Brushless DC Motors are widely used for many industrial applications because of their high efficiency, high
torque and low volume. This paper proposed an improved Adaptive Fuzzy PI controller to control the speed of
BLDC motor. This paper provides an overview of different tuning methods of PID Controller applied to control
the speed of the transfer function model of the BLDC motor drive and then to the mathematical model of the
BLDC motor drive. It is difficult to tune the parameters and get satisfied control characteristics by using normal
conventional PI controller. The experimental results verify that Adaptive Fuzzy PI controller has better control
performance than the conventional PI controller. The modeling, control and simulation of the BLDC motor have
been done using the MATLAB/SIMULINK software. Also, the dynamic characteristics of the BLDC motor (i.e.
speed and torque) as well as currents and voltages of the inverter components are observed by using the
developed model.
Solar fed BLDC motor drive for mixer grinder using a buck-boost converterjournalBEEI
In existing mixer grinders, the universal motor is used due to its high starting torque than the induction motor. To achieve higher speed for smaller devices, the implementation of the universal motor becomes cheaper. The absence of brushes and the reduction of noise in the BLDC extends its lifetime, making it ideal for a mixer grinder. The solar-powered BLDC motor drive for a mixer grinder is presented in this paper. A DC-DC buck boost (BB) converter is utilised to operate the PV (photovoltaic) array at its highest power. The proposed hysteresis current (HC) control BLDC system is developed in the MATLAB. A comparison performance is demonstrated between the commercially available mixer grinder and the simulated proposed system.
Stand-alone applications of Photovoltaic (PV) can be found in water pumping systems for rural area. The proper electric motor must be chosen for optimal considerations. One of the modern electric motor called brushless motor (BLDC) can be an alternative for this application although it has complexity in control. Powering such a motor by using electric energy generating by PV modules will be an interesting problem. In this paper, a PV powered BLDC motor system is proposed. The PV modules must produce maximum power at any instant time and then this power must be able to rotate the motor. By combining sequential stator energizing due to a rotor detection and a PWM concept, the speed of BLDC can be controlled. Meanwhile, to get maximum power of PV modules, detection of voltage and current of the modules are required to be calculated. Digital Signal Control (DSC) is implemented to handle this control strategy and locks the width of the PWM signal to maintain the PV modules under maximum power operation. The effectiveness of the proposed system has been verified by simulation works. Finally the experimental works were done to validate.
Power Quality Analysis of Vienna Rectifier for BLDC Motor Drive ApplicationIJPEDS-IAES
This paper presents the power quality improvements for a BLDC driver using
Vienna rectifier as front end converter. The major drawbacks in the BLDC
motor drive and non linear load applications are the line pollution and
depreciation of the power factor. The conventional power factor correction
method is not economical and efficient. It requires bulky components as load
changes and produce high THD and less Power factor. The front end
converter of BLDC bridge inverter drive is proposed by the Vienna rectifier,
which can contribute more significantly in improving the power factor and
reduce the line pollution. The Vienna rectifier topology is controlled by the
constant switching frequency control technique for wide range of load
variation and it reduces the THD, improve the power factor and provide a
steady DC link voltage to the bridge inverter to drive the BLDC motor. The
design calculation and performance characteristics of BLDC motor and
Vienna rectifier are verified by using Matlab simulation.
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.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Speed Control of Brushless Dc Motor Using Fuzzy Logic Controlleriosrjce
This paper presents a control scheme of a fuzzy logic for the brushless direct current (BLDC)
permanent magnet motor drives. The mathematical model of BLDC motor and fuzzy logic algorithm is derived.
The controller is designed to tracks variations of speed references and stabilizes the output speed during load
variations. The BLDC has some advantages compare to the others type of motors, however the nonlinearity of
the BLDC motor drive characteristics, because it is difficult to handle by using conventional proportionalintegral
(PI) controller. The BLDC motor is fed from the inverter where the rotor position and current
controller is the input. In order to overcome this main problem, the fuzzy logic control is learned continuously
and gradually becomes the main effective control. The effectiveness of the proposed method is verified by
develop simulation model in MATLAB-Simulink program. The simulation results show that the proposed fuzzy
logic controller (FLC) produce significant improvement control performance compare to the PI controller for
both condition controlling speed reference variations and load disturbance variations. Fuzzy logic is introduced
in order to suppressing the chattering and enhancing the robustness of the controlled system. Fuzzy boundary
layer is developed to provide smother transition to the equivalent control. Smaller overshoot in the speed
response and much better disturbance rejecting capabilities.
Torque Ripple Minimization of a BLDC Motor Drive by Using Electronic Commutat...AI Publications
Brushless DC motors are having a major problem with harmonics in torque. The variations in speed and production of noise should be minimized by using proper topologies. BLDC motors have been gaining attention from different Industrial and domestic appliance manufacturers, because of their high efficiency, high power density and easy maintenance and low cost. This paper presents a three phase BLDC motor with low cost drive to be driven without DC link capacitor. The proposed technique uses an electronic commutation and operates the machine exclusive of the intermediate DC link capacitor. The designing of Brushless DC motor drive system along with control system for torque ripple minimization, speed controller and current controllers are presented using MATLAB / SIMULINK and results are evaluated.
Due to availability of internet and evolution of embedded devices, Internet of things can be useful to contribute in energy domain. The Internet of Things (IoT) will deliver a smarter grid to enable more information and connectivity throughout the infrastructure and to homes. Through the IoT, consumers, manufacturers and utility providers will come across new ways to manage devices and ultimately conserve resources and save money by using smart meters, home gateways, smart plugs and connected appliances. The future smart home, various devices will be able to measure and share their energy consumption, and actively participate in house-wide or building wide energy management systems. This paper discusses the different approaches being taken worldwide to connect the smart grid. Full system solutions can be developed by combining hardware and software to address some of the challenges in building a smarter and more connected smart grid.
A Survey Report on : Security & Challenges in Internet of Thingsijsrd.com
In the era of computing technology, Internet of Things (IoT) devices are now popular in each and every domains like e-governance, e-Health, e-Home, e-Commerce, and e-Trafficking etc. Iot is spreading from small to large applications in all fields like Smart Cities, Smart Grids, Smart Transportation. As on one side IoT provide facilities and services for the society. On the other hand, IoT security is also a crucial issues.IoT security is an area which totally concerned for giving security to connected devices and networks in the IoT .As, IoT is vast area with usability, performance, security, and reliability as a major challenges in it. The growth of the IoT is exponentially increases as driven by market pressures, which proportionally increases the security threats involved in IoT The relationship between the security and billions of devices connecting to the Internet cannot be described with existing mathematical methods. In this paper, we explore the opportunities possible in the IoT with security threats and challenges associated with it.
In today’s emerging world of Internet, each and every thing is supposed to be in connected mode with the help of billions of smart devices. By connecting all the devises used in our day to day life, make our life trouble less and easy. We are incorporated in a world where we are used to have smart phones, smart cars, smart gadgets, smart homes and smart cities. Different institutes and researchers are working for creating a smart world for us but real question which we need to emphasis on is how to make dumb devises talk with uncommon hardware and communication technology. For the same what kind of mechanism to use with various protocols and less human interaction. The purpose is to provide the key area for application of IoT and a platform on which various devices having different mechanism and protocols can communicate with an integrated architecture.
Study on Issues in Managing and Protecting Data of IOTijsrd.com
This paper discusses variety of issues for preserving and managing data produced by IoT. Every second large amount of data are added or updated in the IoT databases across the heterogeneous environment. While managing the data each phase of data processing for IoT data is exigent like storing data, querying, indexing, transaction management and failure handling. We also refer to the problem of data integration and protection as data requires to be fit in single layout and travel securely as they arrive in the pool from diversified sources in different structure. Finally, we confer a standardized pathway to manage and to defend data in consistent manner.
Interactive Technologies for Improving Quality of Education to Build Collabor...ijsrd.com
Today with advancement in Information Communication Technology (ICT) the way the education is being delivered is seeing a paradigm shift from boring classroom lectures to interactive applications such as 2-D and 3-D learning content, animations, live videos, response systems, interactive panels, education games, virtual laboratories and collaborative research (data gathering and analysis) etc. Engineering is emerging with more innovative solutions in the field of education and bringing out their innovative products to improve education delivery. The academic institutes which were once hesitant to use such technology are now looking forward to such innovations. They are adopting the new ways as they are realizing the vast benefits of using such methods and technology. The benefits are better comprehensibility, improved learning efficiency of students, and access to vast knowledge resources, geographical reach, quick feedback, accountability and quality research. This paper focuses on how engineering can leverage the latest technology and build a collaborative learning environment which can then be integrated with the national e-learning grid.
Internet of Things - Paradigm Shift of Future Internet Application for Specia...ijsrd.com
In the world more than 15% people are living with disability that also include children below age of 10 years. Due to lack of independent support services specially abled (handicap) people overly rely on other people for their basic needs, that excludes them from being financially and socially active. The Internet of Things (IoT) can give support system and a better quality of life as well as participation in routine and day to day life. For this purpose, the future solutions for current problems has been introduced in this paper. Daunting challenges have been considered as future research and glimpse of the IoT for specially abled person is given in the paper.
A Study of the Adverse Effects of IoT on Student's Lifeijsrd.com
Internet of things (IoT) is the most powerful invention and if used in the positive direction, internet can prove to be very productive. But, now a days, due to the social networking sites such as Face book, WhatsApp, twitter, hike etc. internet is producing adverse effects on the student life, especially those students studying at college Level. As it is rightly said, something which has some positive effects also has some of the negative effects on the other hand. In this article, we are discussing some adverse effects of IoT on student’s life.
Pedagogy for Effective use of ICT in English Language Learningijsrd.com
The use of information and communications technology (ICT) in education is a relatively new phenomenon and it has been the educational researchers' focus of attention for more than two decades. Educators and researchers examine the challenges of using ICT and think of new ways to integrate ICT into the curriculum. However, there are some barriers for the teachers that prevent them to use ICT in the classroom and develop supporting materials through ICT. The purpose of this study is to examine the high school English teachers’ perceptions of the factors discouraging teachers to use ICT in the classroom.
In recent years usage of private vehicles create urban traffic more and more crowded. As result traffic becomes one of the important problems in big cities in all over the world. Some of the traffic concerns are traffic jam and accidents which have caused a huge waste of time, more fuel consumption and more pollution. Time is very important parameter in routine life. The main problem faced by the people is real time routing. Our solution Virtual Eye will provide the current updates as in the real time scenario of the specific route. This research paper presents smart traffic navigation system, based on Internet of Things, which is featured by low cost, high compatibility, easy to upgrade, to replace traditional traffic management system and the proposed system can improve road traffic tremendously.
Ontological Model of Educational Programs in Computer Science (Bachelor and M...ijsrd.com
In this work there is illustrated an ontological model of educational programs in computer science for bachelor and master degrees in Computer science and for master educational program “Computer science as second competence†by Tempus project PROMIS.
Understanding IoT Management for Smart Refrigeratorijsrd.com
Lately the concept of Internet of Things (IoT) is being more elaborated and devices and databases are proposed thereby to meet the need of an Internet of Things scenario. IoT is being considered to be an integral part of smart house where devices will be connected to each other and also react upon certain environmental input. This will eventually include the home refrigerator, air conditioner, lights, heater and such other home appliances. Therefore, we focus our research on the database part for such an IoT’ fridge which we called as smart Fridge. We describe the potentials achievable through a database for an IoT refrigerator to manage the refrigerator food and also aid the creation of a monthly budget of the house for a family. The paper aims at the data management issue based on a proposed design for an intelligent refrigerator leveraging the sensor technology and the wireless communication technology. The refrigerator which identifies products by reading the barcodes or RFID tags is proposed to order the required products by connecting to the Internet. Thus the goal of this paper is to minimize human interaction to maintain the daily life events.
DESIGN AND ANALYSIS OF DOUBLE WISHBONE SUSPENSION SYSTEM USING FINITE ELEMENT...ijsrd.com
Double wishbone designs allow the engineer to carefully control the motion of the wheel throughout suspension travel. 3-D model of the Lower Wishbone Arm is prepared by using CAD software for modal and stress analysis. The forces and moments are used as the boundary conditions for finite element model of the wishbone arm. By using these boundary conditions static analysis is carried out. Then making the load as a function of time; quasi-static analysis of the wishbone arm is carried out. A finite element based optimization is used to optimize the design of lower wishbone arm. Topology optimization and material optimization techniques are used to optimize lower wishbone arm design.
A Review: Microwave Energy for materials processingijsrd.com
Microwave energy is a latest largest growing technique for material processing. This paper presents a review of microwave technologies used for material processing and its use for industrial applications. Advantages in using microwave energy for processing material include rapid heating, high heating efficiency, heating uniformity and clean energy. The microwave heating has various characteristics and due to which it has been become popular for heating low temperature applications to high temperature applications. In recent years this novel technique has been successfully utilized for the processing of metallic materials. Many researchers have reported microwave energy for sintering, joining and cladding of metallic materials. The aim of this paper is to show the use of microwave energy not only for non-metallic materials but also the metallic materials. The ability to process metals with microwave could assist in the manufacturing of high performance metal parts desired in many industries, for example in automotive and aeronautical industries.
Web Usage Mining: A Survey on User's Navigation Pattern from Web Logsijsrd.com
With an expontial growth of World Wide Web, there are so many information overloaded and it became hard to find out data according to need. Web usage mining is a part of web mining, which deal with automatic discovery of user navigation pattern from web log. This paper presents an overview of web mining and also provide navigation pattern from classification and clustering algorithm for web usage mining. Web usage mining contain three important task namely data preprocessing, pattern discovery and pattern analysis based on discovered pattern. And also contain the comparative study of web mining techniques.
APPLICATION OF STATCOM to IMPROVED DYNAMIC PERFORMANCE OF POWER SYSTEMijsrd.com
Application of FACTS controller called Static Synchronous Compensator STATCOM to improve the performance of power grid with Wind Farms is investigated .The essential feature of the STATCOM is that it has the ability to absorb or inject fastly the reactive power with power grid . Therefore the voltage regulation of the power grid with STATCOM FACTS device is achieved. Moreover restoring the stability of the power system having wind farm after occurring severe disturbance such as faults or wind farm mechanical power variation is obtained with STATCOM controller . The dynamic model of the power system having wind farm controlled by proposed STATCOM is developed . To validate the powerful of the STATCOM FACTS controller, the studied power system is simulated and subjected to different severe disturbances. The results prove the effectiveness of the proposed STATCOM controller in terms of fast damping the power system oscillations and restoring the power system stability.
Making model of dual axis solar tracking with Maximum Power Point Trackingijsrd.com
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Speed Control of BLDC Motor with Four Quadrant Operation Using dsPIC
1. IJSRD - International Journal for Scientific Research & Development| Vol. 2, Issue 07, 2014 | ISSN (online): 2321-0613
All rights reserved by www.ijsrd.com 479
Speed Control of BLDC Motor with Four Quadrant Operation Using
dsPIC
Savitri L. Medegar1
M. S. Aspalli2
1
M.Tech student 2
Assistant Professor
1,2
Department of Electrical & Electronics Engineering
1,2
PDA College of Engineering, Gulbarga, Karnataka, India
Abstract— Brushless DC (BLDC) motor drives are
becoming more popular in industrial and traction
applications. Hence the control of BLDC motor in four
quadrants is very vital. The flexibility of the drive system is
increased using digital controller. In this paper the PWM
signals for driving the power inverter bridge for BLDC
motor have been successfully implemented using a dsPIC
controller and the motor can be controlled in all the four
quadrants without any loss of power .Energy is conserved
during regenerative braking period. The digital controller
dsPIC, is advantageous over other controller, as it combines
the calculation capability of digital signal processor and
controlling capability of PIC microcontroller to achieve a
precise control. Simulation of the proposed model is done
by using MATLAB/Simulink.
Key words: BLDC motor, dsPIC, Regenerative braking, four
quadrant
I. INTRODUCTION
In conventional DC motors with brushes, the field winding
is on the stator and armature winding is on the rotor. The
motor is expensive and needs maintenance because of the
brushes, the accumulation of the brush debris and dust, and
commutator surface wear. Moreover, in certain hazardous
locations, the application of DC brushed motors is limited
because of the arcing. This could be solved by replacing the
mechanical switching components (commutator and
brushes) with electronic semiconductor switches. Brushless
DC (BLDC) motor has a permanent magnet rotor and a
wound field stator connected to a power electronic
switching circuit. BLDC motor drives have high efficiency,
low maintenance and long life, low noise, control simplicity,
low weight, and compact construction [1].
The Brushless DC motor is driven by rectangular
or trapezoidal voltage strokes coupled with the given rotor
position. The voltage strokes must be properly aligned
between the phases, so that the angle between the stator flux
and the rotor flux is kept close to 90 to get the maximum
developed torque BLDC motors often incorporate either
internal or external position sensors to sense the actual rotor
position or its position can also be detected without sensors
[2].
BLDC motors are used in Automotive, Aerospace,
Consumer, Medical, Industrial Automation equipments and
instrumentation. In addition, the ratio of torque delivered to
the size of the motor is higher, making it useful in
applications where space and weight are critical factors.
BLDC motor requires an inverter and position sensors that
exposes rotor position for appropriate alternation of current
[2]. To switch the motor stator coils in the correct sequence
and at the correct time, the position of the rotor field
magnets must be known. The exact location of the rotor
field magnets can be detected by Hall Effect sensors or by
an encoder. In this paper, the position information fed to the
controller will be implemented using Hall Effect sensors.
Fig. 1:BLDC motor
The braking of BLDC motors is quite easier as
these machines employ a permanent magnet as its rotor. The
braking methods of a BLDC motor are similar to that of a
direct current machine they are plugging, dynamic and
regenerative[3]. This paper deals with regenerative braking
and simulation results are presented. The braking energy can
be given back to the power source. But it increases the
complexity of the circuit. To overcome this problem an
additional arrangement is used in this paper, it consists of
rectifier, relay and battery. During motoring the relay
contact is opened but when break is applied the relay contact
gets closed. The generated energy is converted into DC by
using rectifier and stored in battery.
Design of robust controllers for a new generation
of full variable-speed control of brushless motor types that
have lower manufacturing cost and higher reliability, saving
up to 25% of the energy used by fixed-speed controllers,
reduced manufacturing and maintenance costs, more
efficient and quieter operation due to less generation of
torque ripple, resulting in less loss of power, lower
vibration, and longer life [6]. In this paper the dsPIC
controllers aredesigned to meet the needs of control-based
applications.
Fig. 2: IGBT inverter
II. BLDC MOTOR AND CONTROLLERS
BLDC motors are a type of synchronous motor as shown in
fig 1. This means the magnetic field generated by the stator
and Brushless DC Motors are driven by DC voltage the
2. Speed Control of BLDC Motor with Four Quadrant Operation Using dsPIC
(IJSRD/Vol. 2/Issue 07/2014/106)
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magnetic field generated by the rotor rotate at the same
frequency. BLDC motors do not experience the “slip” that is
normally seen in induction motors. Brushless DC motors
have been used in various industrial and domestic
applications. Due to overweighing merits of this motor,
there is continuing trend to propose improved control
schemes to enhance the performance of the motor. Current
commutation is controlled by solid state switches. The
commutation instants are determined by the rotor position.
The rotor shaft position is sensed by a Hall Effect sensor,
which provides signals. Whenever the rotor magnetic poles
pass near the Hall sensors, they give a high or low signal,
indicating either N or S pole is passing near the sensors.
Based on the combination of these three Hall sensor signals,
the exact sequence of commutation can be determined.
These signals are decoded by combinational logic to provide
the firing signals for 120° conduction on each of the three
phases. The rotor position decoder has six outputs which
control the upper and lower phase leg IGBTs. IGBT is
selected as power switch for the inverter as shown in fig 2
instead of MOSFET because the former is more suitable for
low voltage and high speed switching application.
Hall
sensor
A
Hall
sensor
B
Hall
sensor
C
Phase
A
Phase
B
Phase
C
1 0 0 NC
1 0 1 NC
0 0 1 NC
0 1 1 NC
0 1 0 NC
1 1 0 NC
Table 1: Commutation sequence for rotating the motor in
clockwise direction
Hall
sensor
A
Hall
sensor
B
Hall
sensor
C
Phase
A
Phase
B
Phase
C
1 0 0
1 1 0
0 1 0
0 1 1 NC
0 0 1 NC
1 0 1
Table 2: Commutation Sequence for rotating the motor in
Counter-clockwise direction
III. FOUR QUADRANT CONTROL OPERATION
There are four possible modes or quadrants of operation as
shown in fig 3 using a Brushless DC Motor. In an X-Y plot
of speed versus torque, Quadrant I is forward speed and
forward torque. The torque is propelling the motor in the
forward direction. Conversely, Quadrant III is reverse speed
and reverse torque. Now the motor is “motoring” in the
reverse direction, spinning backwards with the reverse
torque. Quadrant II is where the motor is spinning in the
forward direction, but torque is being applied in reverse.
Torque is being used to “brake” the motor, and the motor is
now generating power as a result. Finally, Quadrant IV is
exactly the opposite. The motor is spinning in the reverse
direction, but the torque is being applied in the forward
direction. Again, torque is being applied to attempt to slow
the motor and change its direction to forward again. Once
again, power is being generated by the motor i.e. during
breaking motor acts as generator converts the KE into
electrical energy.
The BLDC motor is initially made to rotate in
clockwise direction, but when the speed reversal command
is obtained, the control goes into the CW regeneration mode,
which brings the rotor to the standstill position. Instead of
waiting for the absolute standstill position, continuous
energization of the main phase is attempted. In this paper
instead of energization of main phase energization of battery
is done through rectifier. This rapidly slows down the rotor
to a standstill position. Therefore, there is the necessity for
determining the instant when the rotor of the machine is
ideally positioned for reversal. Hall-effect sensors are used
to ascertain the rotor position and from the Hall sensor
outputs, it is determined whether the machine has reversed
its direction. This is the ideal moment for energizing the
stator phase so that the machine can start motoring in the
CCW direction. Commutation sequence for rotating motor
in clockwise and anti-clockwise diection is shown in table 1
and table 2 respectively.
Fig. 3: Four quadrant operation
Fig. 4:.operating modes
IV. PROPOSED DRIVE SYSTEM
A. Open Loop System
In open loop speed control, the duty cycle is directly
calculated from the set reference speed and there is no actual
speed feedback for control purpose.
The DC voltage source is applied to the inverter;
Inverter output is connected to the 3 phase BLDC motor.
The PWM module of the controller generates appropriate
PWM signals, which are applied to driver circuit which
provides interface between power switch and the control
signal. The PWM signal from driver circuit is given to three
phase IGBT inverter as shown in fig 5. Whenever there is a
3. Speed Control of BLDC Motor with Four Quadrant Operation Using dsPIC
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reversal of direction of rotation it implies there is a change
in the quadrant. When the motor is operating in the motoring
mode, in the clockwise direction, the relay contacts are
normally open. But when braking is applied or when a speed
reversal command is received, the relay contacts are closed.
The kinetic energy which will be wasted as heat energy is
now converted into electric energy which is rectified and
stored in a chargeable battery.
Fig. 5: block diagram of open loop
B. Closed Loop System
The DC voltage source is applied to the inverter; Inverter
output is connected to the 3 phase BLDC motor. The Hall
sensors give the position of the rotor which is fed to the
controller. The controller compares actual speed with the
reference speed and generates an error signal. Depending on
the error signal the PWM module of the controller generates
appropriate PWM signals, and applied to driver circuit
which provides interface between power switch and the
control signal. The PWM signal from driver circuit is given
to three phase IGBT inverter as shown in fig 6.
The position signals obtained from the Hall sensors
of the motor are read by the I/O lines of the dsPIC
controller. Whenever there is a reversal of direction of
rotation it implies there is a change in the quadrant. When
the motor is operating in the motoring mode, in the
clockwise direction, the relay contacts are normally open.
But when braking is applied or when a speed reversal
command is received, the relay contacts are closed. The
kinetic energy which will be wasted as heat energy is now
converted into electric energy which is rectified and stored
in a chargeable battery. The frequent reversal of direction of
rotation will result in the continuous charging of the battery.
The energy thus stored can be used to run the same motor
when there is an interruption of power supply.
Fig. 6: block diagram of closed loop
C. dsPIC Controller
The digital pulse width modulation control of BLDC motor
will be efficient and cost effective. Different types of dsPIC
controllers available like dsPIC30F2011,
dsPIC30F4011/4012. In this paper the digital control of the
four quadrant operation of the three phase BLDC motor is
achieved with dsPIC30F4011. This digital controller
combines the Digital Signal Processor features and
microcontroller features, making it versatile. The
dsPIC30F4011 device contains extensive Digital Signal
Processor (DSP) functionality within high performance 16-
bit microcontroller (MCU) architecture. The PWM module
generates multiple synchronized Pulse width modulation
(PWM) outputs. It has six PWM I/O pins with three duty
cycle generators. The three PWM duty cycle registers are
double buffered to allow updates of PWM outputs. For each
duty cycle, there is a duty cycle register that will be
accessible by the user while the second duty cycle registers
holds the actual compared value used in the present PWM
period. The output compare module generates an interrupt to
trigger the relay circuit during regenerative mode. The
device is programmed in open loop and closed loop using
MPLAB Integrated Development Environment (IDE) tool.
For execution of C-code, MPLAB compiler is used.
D. Relay
The relay circuit is shown in fig 7 whenever there is a
reversal of direction of rotation it implies there is a change
in the quadrant. When the motor is operating in the motoring
mode, in the clockwise direction, the relay contacts are
normally open. But when braking is applied or when a speed
reversal command is received from dsPIC, the relay contacts
are get closed. The K.E which is wasted as heat is rectified
and stored in battery. This energy can be used further when
there is an interruption of power supply.
Fig. 7: Relay
V. REGENERATIVE BRAKING
In locomotives, precise control over stopping of machine is
important along with start. In such a case to stop the
machine quickly and accurately, braking methods are useful.
Braking is nothing but stopping the machine at a desired
position. Braking of locomotive can be done as electric
braking or mechanical braking. In mechanical braking the
motion is restricted by the friction applied by mechanical
brakes which is preferred during low speeds. In electric
braking the motor works as a generator developing a
negative torque which restricts the motion. The purpose of
electrical braking is to restrict the motion of the machine as
quick as possible. In regenerative braking, instead of
wasting the power in external resistance the power
generated during retardation is fed back towards the source
i.e., the motor works as a generator developing a negative
torque which opposes the motion and the generated energy
is supplied to the source. For the generated energy to be
supplied to the source two conditions should be satisfied [4].
(1) Back emf should be greater than supply voltage (E
> V) for all speeds.
(2) Current has to reverse its direction.
4. Speed Control of BLDC Motor with Four Quadrant Operation Using dsPIC
(IJSRD/Vol. 2/Issue 07/2014/106)
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The regenerative breaking in proposed system is as shown in
fig 8. In proposed system when break is applied the relay
contacts are gets closed. The kinetic energy which will be
wasted as heat energy is now converted into electrical
energy and is given back to the power source. But it
increases the complexity of the circuit. To overcome this
additional rectifier, relay and battery is used. Now the
generated energy is rectified and stored in a chargeable
battery. The frequent reversal of direction will result in the
continuous charging of the battery. The stored energy can be
used to run the same motor when there is interruption of
power supply.
Fig. 8: regenerative breaking
VI. Result
The motor is operated in four steady state operating modes
of torque-speed plane. At first, the motor is operated in
forward motoring mode, after 1.5 secbrake is applied i.e.
when a speed reversal command is given; the motor
undergoes braking operation in forward direction, with
speed tending to zero and starts rotating in reverse direction.
When a speed reversal command is issued again i.e, at time
2.3 sec the motor undergoes reverse braking and operates in
Forward Motoring mode. The simulation results for four
quadrant are shown in figure 10 to 14. The Hall sensor
signals are shown in figure 10, the three phase currents Ia,
Ib, Ic are shown in figure 11, the Back EMF Ea ,Eb, Ec is
shown in figure 12,actual speed and reference speed is
shown in figure 13. In this paper 800 rpm is taken as
reference speed. Energization of battery is shown in figure
14. The speed is controlled by proportional integral
controller.
A. simulation result
Fig. 9: Simulation model
Fig. 10: Hall sensor signal A,B,C
Fig. 11: Phase currents Ia, Ib, Ic
BLDC motor simulation model is shown in fig 9 is
simulated using MATLAB/SIMULINK software. The
inputs for the motor model are three phase terminal voltages
and the torque..the motor model gives the three phase
currents, back EMF, speed and rotor position as output. Hall
sensor gives the rotor position. The gate signals are
generated by comparing the actual speed with reference
speed. Thus closed loop control is achieved with the help of
PI control
Fig. 12: Back EMF Ea, Eb,Ec
Fig. 13: Reference speed and Actual speed
5. Speed Control of BLDC Motor with Four Quadrant Operation Using dsPIC
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Fig. 14: Energization of battery
B. Experimental result
Fig 15 shows the hardware implementation of proposed
system consist of power supply board, three phase inverter
board with driver circuit, dsPIC control board, relay
arrangement and a three phase BLDC motor. The
developed three phases Inverter Bridge is connected to
dsPIC through driver circuit (IR2011) which provides
isolation between the power and control side and turns on
and turns off the corresponding switches according to
sequences. A Hall sensor gives the rotor position of motor.
Hall sensor signals A,B are shown in fig 16 .The Hall sensor
inputs give the position of the rotor which is fed to the
dsPIC4011 controller. The controller compares it with the
reference speed and generates an error signal. The required
direction of rotation either clockwise or counter clockwise
can also be fed to the digital controller. Controller generates
the PWM pulses for g1 and g2 are shown in fig 17. These
PWM pulses are applied to the inverter bridge at the
appropriate time to trigger the appropriate switches. Fig 18
shows back EMF Eab similar waveforms are obtained for
back EMF Ebc and Eca but they are displaced one another by
120˚. The phase currents Iais shown in fig 19 respectively.
Initially moor is running in forward motoring mode, after a
time interval break is applied, the motor stops decelerating
at this point the battery starts charging. Output of rectifier is
shown in fig 20. A Digital Storage Oscilloscope has been
used to store
Fig. 15: Hard ware Kit
Fig. 16: Hall Sensor A, C Signal
Fig. 17: PWM gate pulses g1, g2
Fig. 18: Back EMF Eab
Fig. 19: Phase Current Ia
Description Value
Rated voltage 24 V
Rated current 2.3 A
Rated speed 3000 rpm
Rated power 60 W
Number of poles 8
Table 3: BLDC Motor Specification
Experimental values for open loop
Duty Cycle Actual Speed (Rpm)
15 740
25 1285
50 2096
75 2495
85 2597
Table 4: values for Open loop control
Duty Cycle Voltage(V)
15 3.2
25 6.5
6. Speed Control of BLDC Motor with Four Quadrant Operation Using dsPIC
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50 11.8
75 20
Table 5: Generated Voltage during Regenerative Braking
Experimental values for closed loop
Set Speed
(Rpm)
Actual Speed
(Rpm)
300 295
1000 1004
1500 1497
2000 2003
2500 2497
Table 6: Speed Values For Closed Loop
Speed (rpm) Voltage (V)
300 1.8
1000 7.2
1500 11.4
2000 16.7
Table 7: Generated Voltage during Regenerative Braking
VI. CONCLUSION
In this paper a control scheme is proposed for BLDC motor
to change the direction from CW to CCW and the speed
control is achieved. A dsPIC4011 controller is used to
control the speed of the BLDC motor. Speed control is done
in open loop and closed loop by a IGBTs inverter. The
generated voltage during the regenerative mode is stored in
battery which will result in considerable saving of power.
The generated energy can be used to run the motor
whenever there is a power supply failure. This concept may
well be utilized in the rotation of spindles, embroidery
machines, washing machine, fans insmall power application.
In large power application like in industry, electric
locomotive and in satellite where there is frequent reversal
of direction of rotation of the motor taking place.
Advantages of this proposed method are: simple
hardware circuit, excellent speed control, smooth transition
between the quadrants and efficient conservation of energy
during regenerative breaking.
REFERENCES
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