一种改进的CVCF逆变器直接重复控制策略

提出了一种改进型恒压恒频(CVCF)逆变器直接重复控制策略,通过电压微分内环反馈控制有效消除了逆变器固有的高谐振峰,使逆变器稳定性和开环动态特性得以极大的提高,不仅简化了重复控制器的设计,也可获得高品质的输出电压。将该控制策略用于10 kVA三相EPS逆变器中,获得了非线性负载下输出电压总谐波含量低(THD≈1.5%),误差收敛速度快(两个基波周期)的结果。实验证明了理论分析的正确性和控制策略的简单、实用性。

An Improved Direct Repetitive Control Strategy for CVCF Inverter

Combined with an output voltage differential inner loop,an improved direct repetitive control strategy for Con-stant Voltage Constant Freguence(CVCF) inverter is proposed.The output voltage differential feedback effectively elimi-nates the inherent high-resonant peak of the open-loop inverter.Since the stability and the transient characteristics are greatly improved,the repetitive controller is easily to be designed.This method achieves low THD%(about 1.5%) with nonlinear loads and fast error convergence(2 fundamental periods) by a 10 kVA three phase Emergency Power Supply(EPS) prototype developed in lab.It proves to be a simple and cost-effective solution for CVCF inverters.