一种简化的逆变器并联控制技术研究

依据输出有功功率差和无功功率差分别调节输出电压相位和幅值的控制技术较多地应用在逆变器并联控制中.但是,对于基于电压电流双闭环反馈的电压源型逆变器,输出有功功率、无功功率和输出电压相位、幅值均有耦合关系.本文推导出逆变器的等效输出阻抗,研究了有功功率、无功功率和输出电压相位、幅值的定量关系.讨论了器件精度对输出电压跟踪基准电压幅值和相位的影响,在此基础上提出一种简化的并联控制策略:即基准电压同步,根据环流大小调节基准电压幅值.建立了并联系统模型,分析了并联系统特性,给出了实验结果.

A Simplified Control Technique for Inverters in Parallel Operation

The control strategy that regulates the phase and the amplitude of the output voltage according to output active power difference and reactive power difference respectively is adopted generally in inverter parallel techniques. However, active power and reactive power are related to both voltage amplitude and voltage phase for voltage and current double closed-loop feedback voltage-source inverter. This paper deduces the equivalent output impedance of the inverter and discusses the quantitative relationship between active power, reactive power and amplitude and phase of output voltage. The influence of device tolerance on voltage track of output voltage to reference voltage is discussed. Then a simplified parallel control strategy based on phase synchronization and amplitude regulation of reference voltage is proposed and the model of parallel system is established. Performance of parallel system is analyzed and experimental results are given.