Browsing by Author "Wang, Chao-Min"

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A novel twelve-step sensorless drive scheme for a brushless DC motor
(2007-06-01)
Wang, Chao-Min
;
Wang, Shyh-Jier
;
Lin, Shir-Kuan
;
Lin, Hsing-Yu
;
電控工程研究所
This paper presents a novel twelve-step sensorless drive scheme for a three-phase brushless DC motor, which combines the traditional six-step 120 degrees and 180 degrees conduction modes and has varied active angular period. The proposed scheme is implemented on a single FPGA-chip. Several experiments for various active angle periods from 124 degrees to 168.75 degrees are undertaken. The experimental results show that the torque constant is larger for the larger active angular period.
A Simple Single Shunt Current Reconstruction Approach for Low-Cost Permanent Magnet Synchronous Motor Drives
(2015)
Wang, Chao-Min
;
Lin, Shir-Kuan
;
電控工程研究所
;
Institute of Electrical and Control Engineering
This paper presents a simple single-shunt current reconstruction approach in the direct current link (DC-link) for a three-phase voltage source inverter. A space vector pulse width modulation (SVPWM) technique with an adjusting scheme for switching states is investigated. Since three-phase input currents cannot be reconstructed in the unmeasurable area, a unified method for modifying the switching state of the pulse width modulation (PWM) rectifier is proposed. The proposed method can maintain the symmetrical double-sided modulation without changing the total duty cycle of the voltage vector, and the reconstructed three-phase currents approximate the currents measured from the traditional three-shunt sensing circuit. The comparison between a conventional SVPWM technique with adjusting scheme and the proposed approach is demonstrated. Significant simulation results for performance comparison and experimental verification of the current reconstruction scheme show that the proposed method can offer lower current distortion. Hardware implementation is carried out on the basis of an electric fan composed of a three-phase permanent magnet synchronous motor (PMSM) drive system by using a single DC current sensor and an embedded microsystem.
Design and implementation of antihandshaking position control for a voice coil motor
(2008-04-01)
Lin, Shir-Kuan
;
Wang, Chao-Min
;
Wang, Shyh-Jier
;
電控工程研究所
;
Institute of Electrical and Control Engineering
This paper deals with the position control of the voice coil motor (VCM) with handshaking. A disturbance observer is proposed to estimate the low-frequency handshaking disturbance, so that a handshaking-robust controller can be constructed. While a handshaking stabilizer can compensate for the vibration of the whole lens set, a robust controller is still required to precisely hold the autofocusing lens by rejecting the handshaking disturbance. To meet the request of miniaturization, the control is implemented on a field programmable gate array chip. (C) 2008 American Institute of Physics.