Title |
A Study on 6-pulse-shift Current-source PWM Inverterfor Photovoltaic System |
Authors |
Joung-Min Lim ; Sang-Hun Lee ; Sung-Jun Park ; Chae-Joo Moon ; Young-Hak Chang ; Man-Hyung Lee |
Keywords |
Grid-Connected Photovoltaic System; Current-Source PWM inverter; Buck-Boost Converter; Digital Signal Processor |
Abstract |
In order to increase reliability and reduce system cost, this paper studies particularly applicable method for sensorless PM BLDCM drive system. The waveform of the motor internal voltages(or back emf) contains a fundamental and higher order frequency harmonics. Therefore the third harmonic component is extracted from the stator phase voltage. The resulting third harmonic signal keeps a constant phase relationship with the rotor flux for any motor speed and load condition, and is practically free of noise that can be introduced by the inverter switching, making this a robust sensing method. In addition, a simple starting method and a speed estimation approach are also proposed. Some experimental results are provided to demonstrate the validity of the proposed control method. |