带有虚拟阻抗的逆变器并联改进型下垂控制

给出了一种单相电压源逆变器(VSI)并联系统的控制策略.该控制策略应用dq变换得到有功电流和无功电流来替代传统下垂控制中的有功功率和无功功率,降低了负载电压波动对下垂控制方程的影响.为了进一步提高逆变器的输出特性及更大程度上消除环流,在下垂控制的基础上加入了虚拟阻抗控制.相比其他控制方法,该控制策略不但可以使逆变器工作过程实现输出有功功率的均分,而且具有良好的动态特性.同时,无互联线控制方式使得该方法便于逆变器的热插拔和冗余设计.仿真结果证明了该控制方法的可行性和优良性能.;A control strategy for single-phase parallel inverter system is proposed. The control method replace the active and reactive power in conventional droop control by active and reactive current derived from dq transformation. This improvement can decrease the influence from output voltage disturbance. To achieve a better performance in current sharing, virtual impedance concept is applied based on droop control. The parallel system controlled by proposed control strategy not only achieves power uncoupling and power sharing, but also has a better dynamic performance. Meanwhile,the system can achieve hot swappability and scalability with a redundancy option. Finally, the simulation proves the correctness of theoretical analysis