三相并网逆变器内模控制的改进型GDPWM算法(英文)

A Modified GDPWM Algorithm Based on Internal Model Control for Three-phase Grid-connected Inverters

针对单位功率因数并网的三相逆变器,推导三相并网逆变器内模控制方程,建立逆变器输出侧功率因数角随逆变器输出电流幅值变化的函数关系,深入分析传统常规化不连续脉宽调制(general discontinuous pulse width modulation,GDPWM)的特点,提出一种改进型最小开关损耗不连续调制(modified general discontinuous pulse width modulation,M-GDPWM)算法,该算法通过比较三相正弦参考电压之间的瞬时大小关系,或者逆变器输出三相电流的瞬时大小关系,来计算需要注入到三相正弦参考电压中的零序分量,从而无需像传统最小开关损耗不连续调制那样需要实时计算功率因数角,即可实现最小开关损耗控制。仿真与实验结果验证了所提M-GDPWM算法的正确性和有效性。

The internal model control equation of a three-phase grid-connected inverter with a unitary power factor was deduced. The function relationship between the power factor angle and output current at the inverter side was studied. The characteristic of traditional general discontinuous pulse width modulation （GDPWM） was analyzed in detail. A modified GDPWM （M-GDPWM） algorithm with the minimum switching loss was proposed in this paper. Zero-sequence voltage components injected into three-phase sinusoidal reference voltages were generated by comparing instantaneous three-phase sinusoidal reference voltages, or by judging instantaneous three-phase output currents at the inverter side, rather than calculating the power factor angle to minimize switching loss in the traditional GDPWM algorithm. Simulation and experimental results verify the correctness and validity of the proposed M-GDPWM.