DSpaceCRIS@UNITENhttp://dspace.uniten.edu.my/jspuiThe DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.Mon, 19 Aug 2019 15:07:52 GMT2019-08-19T15:07:52Z50191- Modified Direct torque control using algorithm control of stator flux estimation and space vector modulation based on fuzzy logic control for achieving high performance from induction motorshttp://dspace.uniten.edu.my/jspui/handle/123456789/5796Title: Modified Direct torque control using algorithm control of stator flux estimation and space vector modulation based on fuzzy logic control for achieving high performance from induction motors
Authors: Rashag, H.F.; Koh, S.P.; Abdalla, A.N.; Tan, N.M.L.; Chong, K.H.
Abstract: Direct torque control based on space vector modulation (SVM-DTC) protects the DTC transient merits. Furthermore, it creates better quality steady-state performance in a wide speed range. The modified method of DTC using SVM improves the electrical magnitudes of asynchronous machines, such as minimizing the stator current distortions, the stator flux with electromagnetic torque without ripple, the fast response of the rotor speed, and the constant switching frequency. In this paper, the proposed method is based on two new control strategies for direct torque control with space vector modulation. First, fuzzy logic control is used instead of the PI torque and a PI flux controller to minimizing the torque error and to achieve a constant switching frequency. The voltages in the direct and quadratic reference frame (Vd, V q) are achieved by fuzzy logic control. In this scheme, the switching capability of the inverter is fully utilized, which improves the system performance. Second, the close loop of stator flux estimation based on the voltage model and a low pass filter is used to counteract the drawbacks in the open loop of the stator flux such as the problems saturation and dc drift. The response of this new control strategy is compared with DTC-SVM. The experimental and simulation results demonstrate that the proposed control topology outperforms the conventional DTC-SVM in terms of system robustness and eliminating the bad outcome of dc-offset.
Tue, 01 Jan 2013 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/57962013-01-01T00:00:00Z
- Investigation of induction motor parameter identification using particle swarm optimization-based RBF neural network (PSO-RBFNN)http://dspace.uniten.edu.my/jspui/handle/123456789/5820Title: Investigation of induction motor parameter identification using particle swarm optimization-based RBF neural network (PSO-RBFNN)
Authors: Rashag, H.F.; Koh, S.P.; Tiong, S.K.; Chong, K.H.; Abdalla, A.N.
Abstract: High dynamic performance of induction motor drives is required for accurate system information. From the actual parameters, it is possible to design high performance induction motor drive controllers. In this paper, improving the induction motor performance using intelligent parameter identification was proposed. First, machine model parameters were presented by a set of time-varying differential equations. Second, estimation of each parameter was achieved by minimizing the experimental response based on matching of the stator current, voltage and rotor speed. Finally, simulation results demonstrate the effectiveness of the proposed method and great improvement of induction motor performance. © 2011 Academic Journals.
Sat, 01 Jan 2011 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/58202011-01-01T00:00:00Z
- High performance of space vector modulation direct torque control SVM-DTC based on amplitude voltage and stator flux anglehttp://dspace.uniten.edu.my/jspui/handle/123456789/5797Title: High performance of space vector modulation direct torque control SVM-DTC based on amplitude voltage and stator flux angle
Authors: Rashag, H.F.; Koh, S.P.; Chong, K.H.; Tiong, S.K.; Tan, N.M.L.; Abdalla, A.N.
Abstract: Various aspects related to controlling induction motor are investigated. Direct torque control is an original high performance control strategy in the field of AC drive. In this proposed method, the control system is based on Space Vector Modulation (SVM), amplitude of voltage in direct- quadrature reference frame (d-q reference) and angle of stator flux. Amplitude of stator voltage is controlled by PI torque and PI flux controller. The stator flux angle is adjusted by rotor angular frequency and slip angular frequency. Then, the reference torque and the estimated torque is applied to the input of PI torque controller and the control quadrature axis voltage is determined. The control d-axis voltage is determined from the flux calculator. These q and d axis voltage are converted into amplitude voltage. By applying polar to Cartesian on amplitude voltage and stator flux angle, direct voltage and quadratures voltage are generated. The reference stator voltages in d-q are calculated based on forcing the stator voltage error to zero at next sampling period. By applying inverse park transformation on d-q voltages, the stator voltages in α and β frame are generated and apply to SVM. From the output of SVM, the motor control signal is generated and the speed of the induction motor regulated toward the rated speed. The simulation Results have demonstrated exceptional performance in steadand transient states and shows that decrease of torque and flux ripples is achieved in a complete speed range. © Maxwell Scientific Organization, 2013.
Tue, 01 Jan 2013 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/57972013-01-01T00:00:00Z
- DTC-SVM based on PI torque and PI flux controllers to achieve high performance of induction motorhttp://dspace.uniten.edu.my/jspui/handle/123456789/5788Title: DTC-SVM based on PI torque and PI flux controllers to achieve high performance of induction motor
Authors: Rashag, H.F.; Tan, N.M.L.; Koh, S.P.; Abdalla, A.N.; Chong, K.H.; Tiong, S.K.
Abstract: The fundamental idea of direct torque control of induction machines is investigated in order to emphasize the property produced by a given voltage vector on stator flux and torque variations. The proposed control system is based on Space Vector Modulation (SVM) of electrical machines, Improvement model reference adaptive system, real time of stator resistance and estimation of stator flux. The purpose of this control is to minimize electromagnetic torque and flux ripple and minimizing distortion of stator current. In this proposed method, PI torque and PI flux controller are designed to achieve estimated torque and flux with good tracking and fast response with reference torque and there is no steady state error. In addition, design of PI torque and PI flux controller are used to optimize voltages in d-q reference frame that applied to SVM. The simulation Results of proposed DTC-SVM have complete excellent performance in steady and transient states as compared with classical DTC-SVM. © Maxwell Scientific Organization, 2014.
Wed, 01 Jan 2014 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/57882014-01-01T00:00:00Z
- Issues of matrix converters: Technical reviewhttp://dspace.uniten.edu.my/jspui/handle/123456789/5823Title: Issues of matrix converters: Technical review
Authors: Ghoni, R.; Abdalla, A.N.; Koh, S.P.; Rashag, H.F.; Razali, R.
Abstract: Matrix converter is a powerful AC-AC converter for the application of induction motor drives with sinusoidal input currents and no DC-link capacitor. It offers remarkable advantages over other alternatives in applications requiring improved utility interaction and critical weight/volume reduction. This paper presents a technical review on related issues of induction motor drive fed by matrix converters (MC). The first discussions presented the special difficulties involved in matrix converters. These are partly conceptual, partly concerning circuit topology, and current commutation technique. The second discussion analyzes the control and modulation which are of particular interest. The third discussion describes the hardware development modes studies. ©2011 Academic Journals.
Sat, 01 Jan 2011 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/58232011-01-01T00:00:00Z
- Issues and temperature compensation techniques for hot wire thermal flow sensor: A reviewhttp://dspace.uniten.edu.my/jspui/handle/123456789/5825Title: Issues and temperature compensation techniques for hot wire thermal flow sensor: A review
Authors: Khamshah, N.; Abdalla, A.N.; Koh, S.P.; Rashag, H.F.
Abstract: The hot-wire anemometer is used extensively to measure velocity and turbulence quantities. Hot-wire measurement of non-isothermal flows necessitate the use of thermal compensation or error correction. This paper focus of issues and techniques for thermal compensation and error correction in industrial application was studied. Firstly, comprehensive review on the theory of several types of the most commonly used hot-wires anemometry in the field. Secondly, it considered the compensation techniques both in CTA and CCA hot-wire anemometry. Results of compensating techniques are presented for both CTA and CCA and were compare with different techniques. Finally, computational intelligent can be suitable for those systems where it is very complex or impossible to obtain the model by means of classical methods. © 2011 Academic Journals.
Sat, 01 Jan 2011 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/58252011-01-01T00:00:00Z
- Modified Direct torque control using algorithm control of stator flux estimation and space vector modulation based on fuzzy logic control for achieving high performance from induction motorshttp://dspace.uniten.edu.my/jspui/handle/123456789/8998Title: Modified Direct torque control using algorithm control of stator flux estimation and space vector modulation based on fuzzy logic control for achieving high performance from induction motors
Authors: Rashag, H.F.; Koh, S.P.; Abdalla, A.N.; Tan, N.M.L.; Chong, K.H.
Abstract: Direct torque control based on space vector modulation (SVM-DTC) protects the DTC transient merits. Furthermore, it creates better quality steady-state performance in a wide speed range. The modified method of DTC using SVM improves the electrical magnitudes of asynchronous machines, such as minimizing the stator current distortions, the stator flux with electromagnetic torque without ripple, the fast response of the rotor speed, and the constant switching frequency. In this paper, the proposed method is based on two new control strategies for direct torque control with space vector modulation. First, fuzzy logic control is used instead of the PI torque and a PI flux controller to minimizing the torque error and to achieve a constant switching frequency. The voltages in the direct and quadratic reference frame (Vd, V q) are achieved by fuzzy logic control. In this scheme, the switching capability of the inverter is fully utilized, which improves the system performance. Second, the close loop of stator flux estimation based on the voltage model and a low pass filter is used to counteract the drawbacks in the open loop of the stator flux such as the problems saturation and dc drift. The response of this new control strategy is compared with DTC-SVM. The experimental and simulation results demonstrate that the proposed control topology outperforms the conventional DTC-SVM in terms of system robustness and eliminating the bad outcome of dc-offset.
Tue, 01 Jan 2013 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/89982013-01-01T00:00:00Z
- High performance of space vector modulation direct torque control SVM-DTC based on amplitude voltage and stator flux anglehttp://dspace.uniten.edu.my/jspui/handle/123456789/8999Title: High performance of space vector modulation direct torque control SVM-DTC based on amplitude voltage and stator flux angle
Authors: Rashag, H.F.; Koh, S.P.; Chong, K.H.; Tiong, S.K.; Tan, N.M.L.; Abdalla, A.N.
Abstract: Various aspects related to controlling induction motor are investigated. Direct torque control is an original high performance control strategy in the field of AC drive. In this proposed method, the control system is based on Space Vector Modulation (SVM), amplitude of voltage in direct- quadrature reference frame (d-q reference) and angle of stator flux. Amplitude of stator voltage is controlled by PI torque and PI flux controller. The stator flux angle is adjusted by rotor angular frequency and slip angular frequency. Then, the reference torque and the estimated torque is applied to the input of PI torque controller and the control quadrature axis voltage is determined. The control d-axis voltage is determined from the flux calculator. These q and d axis voltage are converted into amplitude voltage. By applying polar to Cartesian on amplitude voltage and stator flux angle, direct voltage and quadratures voltage are generated. The reference stator voltages in d-q are calculated based on forcing the stator voltage error to zero at next sampling period. By applying inverse park transformation on d-q voltages, the stator voltages in α and β frame are generated and apply to SVM. From the output of SVM, the motor control signal is generated and the speed of the induction motor regulated toward the rated speed. The simulation Results have demonstrated exceptional performance in steadand transient states and shows that decrease of torque and flux ripples is achieved in a complete speed range. © Maxwell Scientific Organization, 2013.
Tue, 01 Jan 2013 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/89992013-01-01T00:00:00Z
- Improved close loop stator flux estimation of direct torque control drivehttp://dspace.uniten.edu.my/jspui/handle/123456789/9004Title: Improved close loop stator flux estimation of direct torque control drive
Authors: Rashag, H.F.; Koh, S.P.; Abdalla, A.N.; Tan, N.M.L.; Chong, K.H.; Tiong, S.K.; Jaber, A.S.
Abstract: In conventional direct torque controlled (DTC) induction motor drive, there is usually undesired torque and flux ripple. In this paper close loop stator flux estimation of DTC with space vector modulation under heavy load at low speed was proposed. First, brief description of stator currents in direct-quadrature reference frame with voltage model. Second, close loop stator flux feedback used through PID controller to correct the value of stator flux estimation and eliminate error. In addition, low pass filter also used instead of pure integration to avoid saturation problem. Finally, simulation results show that the flux and torque ripples are greatly reduced when compared with open loop of stator flux estimation. © 2012 Published by Elsevier Ltd.
Sun, 01 Jan 2012 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/90042012-01-01T00:00:00Z
- An optimized 2.4GHz RF power amplifier performance for WLAN systemhttp://dspace.uniten.edu.my/jspui/handle/123456789/9320Title: An optimized 2.4GHz RF power amplifier performance for WLAN system
Authors: Ali, M.H.; Chakrabarty, C.K.; Abdalla, A.N.; Hock, G.C.
Abstract: Recently, the design of RF power amplifiers (PAs) for modern wireless systems are faced with a difficult tradeoff for example, cellphone; battery lifetime is largely determined by the power efficiency of the PA and high spectral efficiency which have ability to transmit data at the highest possible rate for a given channel bandwidth. This paper presents the design a multi stage class AB power Amplifier with high power added efficiency (PAE) and acceptable linearity for the WLAN applications. The open-circuited third harmonic control circuit enhances the efficiency of the PA without deteriorating the linearity of class-AB mode of the PA. The voltage and current waveforms are simulated to evaluate the appropriate operation for the modes. The effectiveness of the proposed controller has been verified by comparing proposed method with another methods using simulation study under a variety of conditions. The proposed circuit operation for a WLAN signals delivers a power-added efficiency (PAE) of 37.6% is measured at 31.6-dBm output power while dissipating 34.61 mA from a 1.8V supply. Finally, the proposed PA is show a good and acceptable result for the WLAN system. © Published under licence by IOP Publishing Ltd.
Tue, 01 Jan 2013 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/93202013-01-01T00:00:00Z
- DTC-SVM based on PI torque and PI flux controllers to achieve high performance of induction motorhttp://dspace.uniten.edu.my/jspui/handle/123456789/8990Title: DTC-SVM based on PI torque and PI flux controllers to achieve high performance of induction motor
Authors: Rashag, H.F.; Tan, N.M.L.; Koh, S.P.; Abdalla, A.N.; Chong, K.H.; Tiong, S.K.
Abstract: The fundamental idea of direct torque control of induction machines is investigated in order to emphasize the property produced by a given voltage vector on stator flux and torque variations. The proposed control system is based on Space Vector Modulation (SVM) of electrical machines, Improvement model reference adaptive system, real time of stator resistance and estimation of stator flux. The purpose of this control is to minimize electromagnetic torque and flux ripple and minimizing distortion of stator current. In this proposed method, PI torque and PI flux controller are designed to achieve estimated torque and flux with good tracking and fast response with reference torque and there is no steady state error. In addition, design of PI torque and PI flux controller are used to optimize voltages in d-q reference frame that applied to SVM. The simulation Results of proposed DTC-SVM have complete excellent performance in steady and transient states as compared with classical DTC-SVM. © Maxwell Scientific Organization, 2014.
Wed, 01 Jan 2014 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/89902014-01-01T00:00:00Z
- Dynamic inverse controller with Matrix Converter Drive Feed Three Phase Induction Motorhttp://dspace.uniten.edu.my/jspui/handle/123456789/11506Title: Dynamic inverse controller with Matrix Converter Drive Feed Three Phase Induction Motor
Authors: Keream, S.S.; Abdalla, A.N.; Daud, M.R.B.; Koh, J.
Abstract: Dynamic inversion (DI) is a controller technique by which existing undesirable dynamics are cancelled out and changed by desirable dynamics. The application of induction motor drives with sinusoidal input currents a matrix converter combined with DI is used which directly connects a three-phase input voltage source to a three-phase (AC-AC converter) without dc-link components. This paper presents a novelty of using nonlinear dynamic inverse controller with matrix converter topologies on three phase induction motor. The efficiency of the converter and their modulation techniques for the implementation of the strategies is increased. The speed response tracking and torque ripple minimization is achieved. The robustness of the proposed method has been confirmed from simulation and experimental model. © 2018 The Authors, published by EDP Sciences.
Mon, 01 Jan 2018 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/115062018-01-01T00:00:00Z
- Fuzzy logic enhanced direct torque control with space vector modulationhttp://dspace.uniten.edu.my/jspui/handle/123456789/11572Title: Fuzzy logic enhanced direct torque control with space vector modulation
Authors: Tan, J.-D.; Koh, S.-P.; Tiong, S.-K.; Ali, K.; Abdalla, A.
Abstract: Over the past few years, multiple types of modifications have been proposed onto the Direct Torque Control (DTC) scheme. Among others is the implementation of Space Vector Modulation (SVM). In this paper, two new control strategies are proposed onto an SVM-DTC. Instead of using PI torque and flux controllers, a fuzzy logic control method is implemented in the proposed modification to achieve a more constant switching frequency while minimizing the torque error. The fuzzy logic controller controls the voltages in direct and quadratic reference frame (Vd, Vq). This approach fully utilizes the switching capability of the inverter and thus improving the overall system performance. To overcome issues in open loop stator flux such as DC drift and saturation, a closed loop estimation method of stator flux is also proposed based on voltage model and low pass filter. The performance of the proposed control strategy is benchmarked with that of a conventional DTC– SVM. Simulations and experiments were carried out and the results show that the proposed method outperforms the conventional DTC-SVM in terms of DC-offset elimination and overall system robustness. © 2018 Institute of Advanced Engineering and Science. All rights reserved.
Mon, 01 Jan 2018 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/115722018-01-01T00:00:00Z
- Fuzzy logic enhanced direct torque control with space vector modulationhttp://dspace.uniten.edu.my/jspui/handle/123456789/10622Title: Fuzzy logic enhanced direct torque control with space vector modulation
Authors: Tan, J.-D.; Koh, S.-P.; Tiong, S.-K.; Ali, K.; Abdalla, A.
Abstract: Over the past few years, multiple types of modifications have been proposed onto the Direct Torque Control (DTC) scheme. Among others is the implementation of Space Vector Modulation (SVM). In this paper, two new control strategies are proposed onto an SVM-DTC. Instead of using PI torque and flux controllers, a fuzzy logic control method is implemented in the proposed modification to achieve a more constant switching frequency while minimizing the torque error. The fuzzy logic controller controls the voltages in direct and quadratic reference frame (Vd, Vq). This approach fully utilizes the switching capability of the inverter and thus improving the overall system performance. To overcome issues in open loop stator flux such as DC drift and saturation, a closed loop estimation method of stator flux is also proposed based on voltage model and low pass filter. The performance of the proposed control strategy is benchmarked with that of a conventional DTC– SVM. Simulations and experiments were carried out and the results show that the proposed method outperforms the conventional DTC-SVM in terms of DC-offset elimination and overall system robustness. © 2018 Institute of Advanced Engineering and Science. All rights reserved.
Mon, 01 Jan 2018 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/106222018-01-01T00:00:00Z
- S55c carbon steel for heat treatment process with different medium in attenuation measurement using ultrasonic testinghttp://dspace.uniten.edu.my/jspui/handle/123456789/11721Title: S55c carbon steel for heat treatment process with different medium in attenuation measurement using ultrasonic testing
Authors: Ali, K.; Paw, J.K.S.; Aizat M.Sulaiman, M.; Abdalla, A.N.; Hen, C.K.; Ding, T.J.
Abstract: Ultrasonic testing or commonly known as UT is one of the non-destructive testing technique and widely used in oil and gas industrial inspection. This technique mostly used in defect or crack identification of the pipeline and also used for flaw detection/evaluation, dimensional measurements, and material characterization. This paper presents the effect of heat treatment for S55C carbon steel in attenuation measurement by using ultrasonic testing including annealing, tempering, and quenching process. Seawater and oil are used as a medium of quenching process. The fixed excitation frequency at 4 MHz is used and 0 degrees with double crystal is implemented in this measurement. The thicknesses of blocks used are as the sample from 30mm until 80mm. The result shows that the measurement of material attenuation will be decreased after annealing, tempering and quenching process from 40% until 99% compared to before the heat treatment process. The highest attenuation decreasing can be seen on the sample block with the 30mm thickness in the heat treatment process. © 2018 Authors.
Mon, 01 Jan 2018 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/117212018-01-01T00:00:00Z
- A novel eddy current testing error compensation technique based on mamdani-type fuzzy coupled differential and absolute probeshttp://dspace.uniten.edu.my/jspui/handle/123456789/11577Title: A novel eddy current testing error compensation technique based on mamdani-type fuzzy coupled differential and absolute probes
Authors: Abdalla, A.N.; Ali, K.; Paw, J.K.S.; Rifai, D.; Faraj, M.A.
Abstract: Eddy current testing (ECT) is an accurate, widely used and well-understood inspection technique, particularly in the aircraft and nuclear industries. The coating thickness or lift-off will influence the measurement of defect depth on pipes or plates. It will be an uncertain decision condition whether the defects on a workpiece are cracks or scratches. This problem can lead to the occurrence of pipe leakages, besides causing the degradation of a company’s productivity and most importantly risking the safety of workers. In this paper, a novel eddy current testing error compensation technique based on Mamdani-type fuzzy coupled differential and absolute probes was proposed. The general descriptions of the proposed ECT technique include details of the system design, intelligent fuzzy logic design and Simulink block development design. The detailed description of the proposed probe selection, design and instrumentation of the error compensation of eddy current testing (ECECT) along with the absolute probe and differential probe relevant to the present research work are presented. The ECECT simulation and hardware design are proposed, using the fuzzy logic technique for the development of the new methodology. The depths of the defect coefficients of the probe’s lift-off caused by the coating thickness were measured by using a designed setup. In this result, the ECECT gives an optimum correction for the lift-off, in which the reduction of error is only within 0.1% of its all-out value. Finally, the ECECT is used to measure lift-off in a range of approximately 1 mm to 5 mm, and the performance of the proposed method in non-linear cracks is assessed. © 2018 by the authors. Licensee MDPI, Basel, Switzerland.
Mon, 01 Jan 2018 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/115772018-01-01T00:00:00Z
- An optimized 2.4GHz RF power amplifier performance for WLAN systemhttp://dspace.uniten.edu.my/jspui/handle/123456789/5695Title: An optimized 2.4GHz RF power amplifier performance for WLAN system
Authors: Ali, M.H.; Chakrabarty, C.K.; Abdalla, A.N.; Hock, G.C.
Abstract: Recently, the design of RF power amplifiers (PAs) for modern wireless systems are faced with a difficult tradeoff for example, cellphone; battery lifetime is largely determined by the power efficiency of the PA and high spectral efficiency which have ability to transmit data at the highest possible rate for a given channel bandwidth. This paper presents the design a multi stage class AB power Amplifier with high power added efficiency (PAE) and acceptable linearity for the WLAN applications. The open-circuited third harmonic control circuit enhances the efficiency of the PA without deteriorating the linearity of class-AB mode of the PA. The voltage and current waveforms are simulated to evaluate the appropriate operation for the modes. The effectiveness of the proposed controller has been verified by comparing proposed method with another methods using simulation study under a variety of conditions. The proposed circuit operation for a WLAN signals delivers a power-added efficiency (PAE) of 37.6% is measured at 31.6-dBm output power while dissipating 34.61 mA from a 1.8V supply. Finally, the proposed PA is show a good and acceptable result for the WLAN system. © Published under licence by IOP Publishing Ltd.
Tue, 01 Jan 2013 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/56952013-01-01T00:00:00Z
- Improved close loop stator flux estimation of direct torque control drivehttp://dspace.uniten.edu.my/jspui/handle/123456789/5814Title: Improved close loop stator flux estimation of direct torque control drive
Authors: Rashag, H.F.; Koh, S.P.; Abdalla, A.N.; Tan, N.M.L.; Chong, K.H.; Tiong, S.K.; Jaber, A.S.
Abstract: In conventional direct torque controlled (DTC) induction motor drive, there is usually undesired torque and flux ripple. In this paper close loop stator flux estimation of DTC with space vector modulation under heavy load at low speed was proposed. First, brief description of stator currents in direct-quadrature reference frame with voltage model. Second, close loop stator flux feedback used through PID controller to correct the value of stator flux estimation and eliminate error. In addition, low pass filter also used instead of pure integration to avoid saturation problem. Finally, simulation results show that the flux and torque ripples are greatly reduced when compared with open loop of stator flux estimation. © 2012 Published by Elsevier Ltd.
Sun, 01 Jan 2012 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/58142012-01-01T00:00:00Z
- Dynamic inverse controller with Matrix Converter Drive Feed Three Phase Induction Motorhttp://dspace.uniten.edu.my/jspui/handle/123456789/11089Title: Dynamic inverse controller with Matrix Converter Drive Feed Three Phase Induction Motor
Authors: Keream, S.S.; Abdalla, A.N.; Daud, M.R.B.; Koh, J.
Abstract: Dynamic inversion (DI) is a controller technique by which existing undesirable dynamics are cancelled out and changed by desirable dynamics. The application of induction motor drives with sinusoidal input currents a matrix converter combined with DI is used which directly connects a three-phase input voltage source to a three-phase (AC-AC converter) without dc-link components. This paper presents a novelty of using nonlinear dynamic inverse controller with matrix converter topologies on three phase induction motor. The efficiency of the converter and their modulation techniques for the implementation of the strategies is increased. The speed response tracking and torque ripple minimization is achieved. The robustness of the proposed method has been confirmed from simulation and experimental model. © 2018 The Authors, published by EDP Sciences.
Mon, 01 Jan 2018 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/110892018-01-01T00:00:00Z