Sensorless And Independent Speed Control Of Dual-PMSM Drives Using Five-Leg Inverter (FLI)

This research aims to develop and implement a combined sensorless and independent speed control for dual-PMSM (Permanent Magnet Synchronous Motor) drives fed by a single Five-Leg Inverter (FLI). Dual-motor drives are widely used in high traction power industry such as propulsion system, aircraft, locomotive, Hybrid Electric Vehicle (HEV) and others. In general, dual-motor drives are designed to reduce size and cost with respect to single motor drives. However, dual-motor drives using a single three-leg inverter has its limitation in the case of operation at different operating conditions and independent speed control requirement. Recent research has shown that, dual motor drives can be independently controlled by using Five-Leg inverter (FLI). By employing this FLI topology, the dual-motor drives can be used for four-quadrant control, variable speed operation and load disturbance rejection. In other words, it can be operated for different applications. In the case of conventional dual-PMSM drives, the drives system still requires current sensors and voltage transducers for speed and rotor position estimation. In PMSM drives, the information of the feedback speed and rotor angular position is compulsory. Therefore, this research is trying to implement a combined sensorless and independent speed control for dual PMSM drives system and at the same time eliminating the usage of voltage transducers. This thesis investigates the behavior of sensorless and independent speed control for Dual-Permanent Magnet Synchronous Motor (PMSM) drives. Initially, a single PMSM drives is designed and simulated, followed by the development of Dual-PMSM drives model. The speed and current controllers are implemented in d-q rotor reference frame using Simulink/MATLAB and the switching signals are generated by the built-in function and dSPACE. Then, the sensorless drive system is developed based on adaptive speed and position estimator. The overall performance of the drives is investigated and evaluated in terms of speed responses overshoot under variation of speed reference and speed drop under load torque disturbances. The simulation results have proved that the performance characteristics of sensorless dual-PMSM are almost similar with system using sensor except during the start-up condition. The motor performance is degraded in terms of speed overshoot for small and medium speed reference or when the motor operates far from the designed operating condition (rated value). The proposed independent dual-PMSM drives fed by FLI have better load rejection capability compared with conventional dual-PMSM drives fed by single three-phase inverter. The experimental results of the drives under investigation have shown acceptable correlation between the theoretical and simulation

Comparative analysis of simplified and standard fuzzy logic controller in vector controller PMSM

This paper presents a comparative analysis of simplified fuzzy logic controller (FLC) for speed performance in vector-controlled permanent magnet synchronous motor (PMSM) drive. The control strategy focuses on fuzzy rule basewhich are contribute to some level of output in obtaining the desired performance. The objective of this research is minimizing the number of rule base used by the PMSM drive besides erform desired output. Two FLCs with reduced rule base (9- rules and 7-rules) are designed and the performance results are compared and ernluated with the standard FLC (49-rules). The simplification of rule base is determined by eliminating some of rule bases that are infrequently fired by the PMSM drive. The standard FLC consists of 49-rules which are determined based on common criteria from many literatures. Two simplified FLCs consist of 9-rules and 7-rules are obtained by knowledge and experience. The simulation results show both simplified FLCs obtain nearly equivalent performance with the standard FLC. The performance of all FLCs over load disturbance and parameter variations are compared a

Differential Evolution Technique Of HEPWM For Three-Phase Voltage Source Inverter

This paper presents the execution of Differential Evolution (DE) algorithm in order to understand the principle operation of Harmonic Elimination Pulse-Width Modulation (HEPWM) switching technique. HEPWM utilizing the DE technique is proposed to eliminate low frequency harmonic components of three-phase inverter output voltage. Explanation of DE algorithm execution is given and the best approach of mutation strategy used in DE has been investigated. Switching angles of HEPWM are calculated offline by using the DE technique. Subsequently, the calculated switching angles are used to operate the three-phase voltage source inverter. Computation of DE algorithm and simulation of voltage source inverter using the calculated switching angles are carried out by using Matlab/Simulink software package. Simulation results show the effectiveness of proposed DE technique in eliminating the low order harmonic components of output voltage for three-phase voltage source inverter

Simulation Single Phase Active Filter Based on p-q technique using MATLAB/Simulink Development Tools Environment

This paper presents a single phase shunt active power filter based on instantaneous power theory. The active filter will be connected directly to utility in order to reduce THD of load current, in this case the utility is TNB.The instantaneous power theory also known as p-q theory is used for three phase active filter and this paper proves that the p-q theory can also be implemented for single phase active filter. Since the system has only single phase signal for both voltage and current, thus the dummy signal with 120º different angels must be generated for input of the p-q theory. The p-q technique will generate six signals PWM for switching IGBT, but only two of the signals will be used to control the switching IGBT. The simulation results are on MATLAB/Simulink environment tools presented in order to demonstrate the performance of the current load on single phase shunt active power filter

Simulation single phase shunt active filter based on P-Q technique using matlab simulink development tools environment

This paper presents a single phase shunt active power filter based on instantaneous power theory. The active filter will be connected directly to utility in order to reduce THD of load current, in this case the utility is TNB. The instantaneous power theory also known as p-q theory is used for three phase active filter and this paper proves that the p-q theory can also be implemented for single phase active filter. Since the system has only single phase signal for both voltage and current, thus the dummy signal with 120 o different angels must be generated for input of the p-q theory. The p-q technique will generate six signals PWM for switching IGBT, but only two of the signals will be used to control the switching IGBT. The simulation results are on MATLAB/Simulink environment tools presented in order to demonstrate the performance of the current load on single phase shunt active power filter

Speed drive based on torque slip characteristic of the single phase induction motor

Most of the researches for adjustable speed drive focused on voltage amplitude control. However, its only control speed in the constraint limits. Adjustable frequency drives have not been widely used with single-phase induction motors. The scalar control law used for many three-phase inductions motor cannot be used in all operating regimes of the single-phase motor. Calculations show that the slip of the single-phase induction motor is not constant with changes in frequency at a constant load torque. A constant 'volts per hertz' law is found to give approximate rated torque over a portion of the upper speed range, but the maximum available torque decays rapidly below 50% of the base frequency. This paper aims to study the behavior of the single phase induction motor's torque and slip characteristic under variable frequency operation. By holding the level of magnetization constant, a control law can be achieved. This method is implemented for the practical adjustable speed of the single-phase induction motor. If time permit, the final draft paper includes the practical experimental results to compare the simulation results in order to achieve satisfactory agreement for torque and slip behavior of single-phase induction motors driven from variable frequency supplie

Computer aided education on special transformer as interactive approach in power engineering education

Due to the popularity of the internet, e-learning has become a new method of learning in recent years. Through the internet, users can freely absorb new knowledge without the restriction of time and place. With this method, there is no need for books because the references materials can be downloaded. The usage of books as reference might be boring and may not attract certain students to study in a long period. Hence, e-learning might be option method to overcome the problem. E-learning provides interactive graphic, animation and interaction between users and the program itself. This paper proposed the usage of e-learning in power engineering education environment. The Computer Aided Education on Special Transformer (CAEOST) software has been developed to provide information about the equipments used in power engineering such as autotransformer, current transformer and voltage transformer. This software has covered the basic operation, applications, tutorial and also virtual lab of the special transformers in interactive and attractive approaches.The usage of interactive animations graphic, buttons and the user friendly approaches attracted users to use the e-learning and able to understand the content easily

Investigation Of Different Rules Size FLSC Performance Applied To Induction Motor Drive

Fuzzy Logic Controller (FLC) has been widely used in speed controller due to its superior performance results. It is suitable when the system is difficult to model mathematically due to its nonlinearity and complexity. There are three common number of rules design which are commonly used in FLSC known as 49, 25 and 9 rules. However, the majority of the previous research report mainly focused on the dedicated rules size design either 49, 25 or 9 rules for the optimum performance. There is lack of performance comparison between 49, 25 and 9 rules size. Thus, it is difficult to understand how the rules size affects the motor performance. This research tries to fill up the gap by comparing the controller performance using the same platform. The fuzzy logic speed controllers (FLSC) with a different type of rules base are applied to the induction motor drive system. The FLSC with 49, 25 and 9 rules are investigated through MATLAB/SIMULINK and performance comparisons are made covering a wide speed range operations and load disturbance. The simulation results are evaluated based on the rise time

Speed sensorless control for PMSM drives using Extended Kalman Filter

In this paper, Sensorless Permanent Magnet Synchronous Motor (PMSM) using Extended Kalman Filter (EKF) is presented. The previous PMSM drive uses a sensor to measure the motor’s speed. Then the idea is to replace the sensor by using sensorless drives based on the observer. For the conventional observer, it’s only good for low current and low-speed applications. Moreover, it is hard to detect the phase voltage due to the non-existence of neutral wire. Therefore, this project proposes sensorless control using an EKF. This method provides an optional estimation algorithm for the non-linear system that can produce a fast and accurate estimation of state variables. The accurate estimation will reduce the noise and ripple of the system. Additionally, the EKF do not require the information of mechanical parameters and the initial position of the rotor, making the construction is easy and simple. In this paper, the fundamental of the EKF algorithm is explained and the simulation results for different speeds and loads are presented. The noise reduction test is also conducted to measure the flux current with and without the filter. The simulation study is achieved using MATLAB/Simulink to verify the effectiveness of the proposed method. The results of the simulation show that the sensorless PMSM drives using EKF have lower overshoot and faster rise time during start-up conditions and have lower undershoot during the loaded condition. It also can be concluded that the proposed sensorless PMSM drive using EKF has good speed control accuracy and can reduce the current noise