摘要
Total harmonic distortion (THD) is one of the key technical indexes of inverter output voltage. Optimization o f switching points and filter parameters could ensure the switching-point-preset sinusoidal pulse width modulation (SPWM) inverters with low harmonyic content in theory.The THD value would be increased by switching time delay of power devices and control circuit. A new control coecuit with delay time compensation is presented in this paper. With this control scheme, the output of the inverter could be basically identified with the theory given.Test results of experimental circuit verify that the control circuit presented in this paper is feasible. The THD of the inverter output voltage could be reduced to a certain extent by this method.
输出电压总谐波含量（ＴＨＤ）是逆变器的关键技术指标之一．优选开关点和输出滤波器参数可以从理论上保证开关点预置ＳＰＷＭ逆变器具有较小的ＴＨＤ。实际电路中，功率器件和控制电路的开关延时会导致ＴＨＤ的增加，本文提出一种具有延时实时补偿的波形闭环控制电路，采用该控制方案，可以保证逆变器的实际输出和理论输出的基本一致，从而得到良好的输出电压波形。本文给出了电路主要部分的设计思想。通过实际电路测试，验证了本文提出的控制方案的可行性，较大程度地减小了逆变器输出电压的ＴＨＤ．
