入力側의 高調波低減을 위한 PWM 電流注入方式 = PWM Current Injection Method for Reducing the Harmonics of Input Side

다국어 초록 (Multilingual Abstract)

Thyristor converters have been widely used in the various industrial fields instead of the mechanical converters since the advent of power semiconductor devices. But the switching operation of these converters makes the current waveform changed abruptly in their input side. Also the nonlinearity of them to ac voltage source gives rise to harmonics and it can be regarded as the harmonic current generator by which many serious problems may be caused in ac power system.
In this paper, the PWM current injection method is suggested and analyzed which can suppress the harmonic contents in ac lines. As a result, the PWM current injection can make the contents of the current harmonics, particularly the lower-order harmonics, reduced to the small amounts. In case of adjusting the magnitude of injection current, its optimum value Id* can be determined to minimize the distortion factor of current.
AC chopper circuit with R-L load is considered as a nonlinear load model to investigate the harmonic-eliminating characteristics for the injection method. And all the computation results are obtained through the digital computer simulation.

목차 (Table of Contents)

• Ⅰ.서론
• Ⅱ.고조파전류 보상방식
• 1.고조파억제 원리
• 2.보상전류원의 실현
• Ⅲ.보상전류의 펄스폭변조
• Ⅳ.고조파저감특성의 해석
• 1.전원전류의 고조파스팩트럼
• 2.왜형율
• Ⅴ.결론