并联逆变器的输出功率分布研究

建立了电压电流双闭环反馈控制逆变器数学模型,指出逆变器PI参数和电流电压反馈系数对输出阻抗影响显著,并得到了输出阻抗计算公式。分析了逆变器并联时,各模块输出功率不平衡的原因。在一定情况下,两逆变器模块输出电压相位差和幅值差均能引起输出的有功功率和无功功率不平衡,并且输出的有功功率差和无功功率差存在一定的比例关系,最后通过仿真和实验验证了上述结论。

Study of the Output Power Distribution of Paralleling Inverter

The authors establish a mathematical model of the inverter which is based on instantaneous output-voltage and filter-inductor-current double closed-loop feedback control, and point out that not only the voltage and current feed-back modulus, but also the PI parameter can influence the inverter's output impedance,and give the formula about how to calculate the output-impedance. The cause of output power unbalance between paralleled inverters is analyzed. In some condition, the difference of amplitude and phase between paralleling module's output voltage will cause the difference of active and reactive output power. Furthermore, these two power differences will change in proportion. The simultion analy-sis and experimental results verify this characteristic.This work is supported by Aeronautics Science Fund of China (No.01F52032) and National Natural Science Fund of China (No.50337030).