Browsing by Author "Lin, Jau-Nan"

Now showing 1 - 3 of 3

A Discontinuous Space Vector PWM Algorithm in abc Reference Frame for Multilevel Three-Phase Cascaded H-Bridge Voltage Source Inverters
(2017-11-01)
Hu, Jwu-Sheng
;
Lin, Jau-Nan
;
Chen, Hung-Chi
;
電機工程學系
;
Department of Electrical and Computer Engineering
Previous space vector pulse-width modulation (SVPWM) methods for a multilevel three-phase voltage source inverter (VSI) have the problems including the computational complexity to identify the location of the reference voltage vector, the memory requirements of switching states and corresponding duty ratios, or no generalized switching pulse durations of switches. These problems are related to the level number, and they become critical at a high level number. In this paper, a discontinuous SVPWM algorithm in the abc reference frame is first proposed for a multilevel three-phase cascaded H-bridge (CHB) VSI. The L-level three-phase SVPWM problem is solved based on the two-level three-phase SVPWM one. Thus, the computational complexity to determine the nearest three switching states and corresponding duty ratios is independent of the level number. Furthermore, the proposed algorithm provides a systematic approach to calculate the switching pulse durations for a multilevel three-phase CHB VSI, and the approach can be extended to different multilevel three-phase VSIs. The proposed algorithm has no memory requirement and low computational complexity. It is verified by the simulation and experimental results for a five-level three-phase CHB VSI.
Voltage Source Inverter Drive Using Error-compensated Pulse Width Modulation
(2016-01)
Chen, Keng-Yuan
;
Hu, Jwu-Sheng
;
Lin, Jau-Nan
;
電控工程研究所
;
Institute of Electrical and Control Engineering
An error-compensated pulse width modulator (ECPWM) is proposed to improve the baseband harmonic performance and the switching loss of voltage source inverters (VSIs). Selecting between harmonic distortion and switching loss is a design tradeoff in the conventional space vector pulse width modulation. In this work, an accumulated difference in produced and desired phase voltages is considered to adjust the reference signal. This mechanism can compensate for the voltage error in the previous carrier period. With error compensation every half-carrier period, the proposed ECPWM allows one-half reduction in carrier frequency without scarifying baseband harmonic distortion. The proposed modulator is applied to a three-phase VSI with R-L load and a motor-speed-control system for experiments. The measured efficiency and operating temperature of switches confirm the effectiveness of the proposed scheme.
Voltage Source Inverter Drive Using Error-compensated Pulse Width Modulation
(2016-01-01)
Chen, Keng-Yuan
;
Hu, Jwu-Sheng
;
Lin, Jau-Nan
;
電控工程研究所
;
Institute of Electrical and Control Engineering
An error-compensated pulse width modulator (ECPWM) is proposed to improve the baseband harmonic performance and the switching loss of voltage source inverters (VSIs). Selecting between harmonic distortion and switching loss is a design tradeoff in the conventional space vector pulse width modulation. In this work, an accumulated difference in produced and desired phase voltages is considered to adjust the reference signal. This mechanism can compensate for the voltage error in the previous carrier period. With error compensation every half-carrier period, the proposed ECPWM allows one-half reduction in carrier frequency without scarifying baseband harmonic distortion. The proposed modulator is applied to a three-phase VSI with R-L load and a motor-speed-control system for experiments. The measured efficiency and operating temperature of switches confirm the effectiveness of the proposed scheme.