CAJ | 학술논문

三相PWM变换器并联以及载波移相的使用能够显著增大变流器的容量并提高交流侧的电能质量，但直接并联会使系统内部产生环流，从而导致变换器损耗增加甚至系统崩溃。通过分析模块并联系统零序环流产生的原理，得出环流大小与零序开关状态相关，从而提出了一种双载波正弦脉宽调制(sinusoidal pulse width modulation，SPWM)控制方法，通过对开关状态的调整来实现抑制环流。该方法不需要增加额外的硬件，具有动态响应快、环流抑制效果好等优点。仿真和实验结果验证了所提控制策略的有效性。
삼상PWM변환기병련이급재파이상적사용능구현저증대변류기적용량병제고교류측적전능질량，단직접병련회사계통내부산생배류，종이도치변환기손모증가심지계통붕궤。통과분석모괴병련계통령서배유산생적원리，득출배류대소여령서개관상태상관，종이제출료일충쌍재파정현맥관조제(sinusoidal pulse width modulation，SPWM)공제방법，통과대개관상태적조정래실현억제배류。해방법불수요증가액외적경건，구유동태향응쾌、배류억제효과호등우점。방진화실험결과험증료소제공제책략적유효성。
The utilization of parallel connection of three-phase PWM converter and carrier phase-shifting can enlarge the capacity of converters obviously and improve the power quality at AC side, however the direct parallel connection of PWM will cause circulating current inside the converter system, it leads to the increase of power loss in converters and even makes the converter system collapsed. On the basis of analyzing the reason to produce zero-sequence circulating current in parallelly connected module system, a conclusion that the size of circulating current is related with the state of zero-sequence switch, and a dual carrier sinusoidal pulse width modulation (SPWM) control strategy, which suppress the circulating current by adjusting the switch state and needs not additional hardware, is proposed. The proposed control strategy possesses advantages such as fast dynamic response and satisfied circulating current suppression effect. Results of both simulation and experiments show that the proposed control strategy is effective.