Zulkifilie Ibrahim

Dual motor drives for PMSM using average phase current technique

Dual motor drives designs are attractive for high power application because of their mechanical simplicity, traction and regenerative braking control on low friction surfaces. However, such configurations normally require two power inverters with coordinated control. The high cost and large size of packaging needs of the inverters make such dual inverter, dual motor drive configurations economically less competitive. Therefore, the need for dual motor drives fed by single inverter rising consequently to reduce sizes and costs with respect to the single motor drives, either in industrial or in traction application. This paper aims to investigate the behavior of dual motor drives fed by single inverter using averaging technique. MATLAB/Simulink has been chosen as the simulation tools. And the averaging technique that has been used is mean phase current method. The results show that the technique that has been applied gives the significant responses due to reference value given.

Comparative study of fuzzy logic speed controller in vector controlled PMSM drive: Minimum number of fuzzy rule-base

This paper presents a comparative study on fuzzy rule-base of fuzzy logic speed control with vector-controlled Permanent Magnet Synchronous Motor (PMSM) drive. Fuzzy rule-base design is viewed as control strategy. All fuzzy rules contribute to some degree in obtaining the desired performance. However, some rules fired weakly do not contribute significantly to the final result and can be eliminated. ‘Standard design’ of fuzzy rule-base of fuzzy logic controller is identified from numerous publications which is 49 rules is used in order to obtain great speed tracking response. It is possible to minimize the complexity of controllers design by reducing number of rule-base from standard 49 rules to 9 rules. Simulation results that verify appropriateness of the approach are included. A comparison of speed response between both designs is studied. Sensitivity of the designs to load disturbance and changes in command settings is studied and also being compared to demonstrate the effectiveness of the reduced rule-base.

Performance comparison of SVPWM and Hysteresis Current Control for Dual motor drives

Dual motor drives fed by single inverter are purposely designed to reduced sizes and cost with respect to single motor drives fed by single inverter. This paper presents the speed responses behavior of Dual Permanent Magnet Synchronous Motor (PMSM) driven base on two different PWM control schemes, which are Space Vector Pulse Width Modulation (SVPWM) and Hysteresis Current Controller. These two techniques are compared for wide range of speed and for variation of load. MATLAB/Simulink has been chosen as the simulation tools. The comparison between SVPWM controller and Hysteresis Current Controller for Dual PMSM fed by single inverter is presented. Both techniques show satisfactory speed regulation for a wide range of speed either with load, no load or variation of load.

Independent speed sensorless control of dual parallel PMSM based on Five-Leg Inverter

This paper introduces a sensorless technique to drive independently dual Permanent Magnet Synchronous Motors (PMSM) based on Five-Leg Inverter (FLI). The main purpose of the proposed method is to eliminate the usage of speed sensor and to reduce the number of inverter switches from twelve to ten switches in the case of dual three-phase PMSMs drives. Despite the needs of speed sensor as the speed feedback for the dual PMSMs drives, there are no research done using sensorless technique in order to control independently dual three-phase PMSMs. A FLI contents ten switches which two switches represent as on e leg. For the five legs available, one leg is commonly connected to both PMSMs. The drive is simulated by using MATLAB/Simulink. The simulation results of the performance for Dual PMSMs fed by a FLI at rated speed are successfully achieved and offer potential result for hardware implementation. The applied technique shows good speed regulation and proves that Dual PMSMs can independently control at different speed operation either in forward or reverse operating conditions as well as for load disturbance.

Performance improvement of induction motor drive using simplified FLC method

This paper presents the improvement method for simplified Fuzzy Logic Controller (FLC) for Induction Motor Drive. This method is aimed to enhance performance for variable speed drive performance in a rated forward and reverse operation. The implementation of simplified rules based is able to reduce the computational burden and memory space limitation. However, the speed performance shows some degradation with regards to simplification process. Thus, the propose improvement method is made to increase the error gain parameter. The membership function (MF) domain for error is increased from nominal 1 to 2. It increases the torque current and improves the speed response. The speed control is applied to the indirect Field Oriented Control method fed with Space Vector Pulse Width Modulation (SVPWM). The real time implementation is done using dSPACE DS1103 controller. The performance results are compared between simplified rules method, simplified rules improvement method and Anti-Windup Proportional Controller (AWPI). The results show improvement in terms of rise time, overshoot and settling time compared to its counterparts.

Implementation of Space Vector Two-Arm Modulation for Independent Motor Control Drive Fed by a Five-Leg Inverter

This paper presents the implementation of two-arm modulation (TAM) technique for the independent control of a two-induction motor drive fed by a five-leg inverter (FLI). A carrier-based space vector pulse width modulation technique for TAM is proposed to generate switching signals for FLI. Two independent three-phase space vecto modulators are utilized to control two motors. The motor drive system applies two separate indirect field-oriented control methods. The stationary voltage outputs from the vector control are synthesized in the three-phase space vector modulator to generate switching signals for FLI. The performance of the independent control of the motors and the voltage utilization factor are likewise analyzed. Simulation and experimental results verify the effectiveness of the proposed method for the independent control of the two-motor drive system. The proposed technique is successfully validated by dSPACE DS1103 experimental work.

Vector control drive of permanent Magnet Synchronous Motor based dSPACE DS1103 implementation

This paper presented a vector controlled drives of permanent Magnet Synchronous Motor (PMSM) by using Proportional-Integral (PI) Speed controller based dSPACE implementation. The concept of vector control is applied to PMSM to obtain linear dynamics similar to that of a DC motor. The model consist of two control loops, hysteresis current controller is used for inner loop current control and PI controller for outer loop speed control. PI speed controller selected due to simplicity compare to fuzzy, neutral etc. to make sure dSPACE DS1103 successfully implemented. The PMSM vector control algorithm for a theoretical basic has been verified by experimental results and created a rapid control prototype environment by using MATLAB/ Simulink and the DS1103 DSP of dSPACE.

A five level cascaded H-bridge inverter based on space vector pulse width modulation technique

Multilevel inverters brought a tremendous revolution in high power superior performance industrial drive applications. Minimizing harmonic distortion is a challenging issue for power electronic drive. This problem can be solved by developing suitable modulation technique. There are number of modulation techniques established in the last decade. Among them, the space vector pulse width modulation (SVPWM) is extensively used because of their easier digital realization, better DC bus utilization and lower THD. Conventional SVPWM requires different number of logical computations of on time calculations and different number of lookup table for each triangle due to having their different number of switching states. In this paper, a simple SVPWM is presented where proposed only four logical computations of on time calculation, four active switching states and four lookup table for each triangle. Five level cascaded h-bridge inverter (CHBI) based on SVPWM technique are modeled and analyzed by using MATLAB/Simulink and origin 6.1 with a passive R-L load that can be extended to any level. These results are compared with other lower levels of inverter and with previous established results. From these results, five level CHBI based on SVPWM shows better performance compared to others in terms of THD.

Sensorless adaptive speed control for PMSM drives

The simplified mathematical model of the permanent magnet synchronous motor is developed in this paper. Speed and torque controls of permanent magnet synchronous motors are usually attained by the application of position and speed sensors yet, speed and position sensors require the additional mounting space, reduce the reliability in harsh environments and increase the cost of the motor. Therefore, many studies have been performed for the elimination of speed and position sensors. Therefore, a V-I model based model reference adaptive control is proposed. A Model Reference Adaptive Control (MRAC) has been formed using parameter uncertainty cancellation to estimate the speed without using any sensor. Firstly, the speed estimation errors of a voltage and current model-based adaptive speed due to the parameter variation are analyzed. Consequently, an adaptation mechanism model is developed to cancel the effects of parameter variations on the estimated speed performance. Finally, the speed control with quantitative control performance considering the effect due to the feedback of estimated speed is presented. The results show that the MRAC is superior to the conventional PI controller in dynamic performance and steady precision. The effectiveness of the proposed controller is demonstrated by some simulation by using MATLAB/SIMULINK.

Hysteresis current control of induction motor drives using dSPACE DSP controller

Hysteresis current control is relatively a simple method for PWM technique with comparatively good current loop response. This paper presents the hardware implementation of hysteresis current control for vector controlled induction motor drives using dSPACE DSP. The analysis is focused on the effect of hysteresis bandwidth to the motor current quality. The hysteresis technique is implemented by using MATLAB/Simulink. The software is linked to the hardware by using dSPACE Real-Time Interface. The experimental rig consists of voltage source inverter, current sensor, induction motor equipped with encoder and PMDC motor coupled with resistor bank as a load. The speed response under various operating conditions and load disturbances are presented to evaluate the drive performance. In order to analyze the performance of hysteresis current controller, the size of the hysteresis band are varied and harmonic content within the stator current is measured in terms of Total Harmonic Distortion (THD). Based on the results, the hysteresis bandwidth has no major effect on the speed response but significantly affects the quality of the motor stator current. Therefore, the small hysteresis bandwidth is desired with consideration on the drives limitation.