逆变器参数不匹配微电网改进下垂策略

针对逆变器线路阻抗和逆变器参数不匹配以及本地负载不均衡的微电网系统,提出一种改进的P-V控制策略,该策略计算各个分布式发电单元输出有功功率的平均值,然后将平均值与本地有功功率测量值作差,利用该差值的积分项对输出电压幅值进行补偿,从而实现高精度的功率均分。该方法使系统具有很好的稳定性和动态性能,在复杂的微电网结构中也能得到很好的功率均分效果,能够实现不同功率等级逆变器间功率的精确分配。仿真和实验结果证明了方案的正确性。

Improved droop control strategy for inverters of mismatch parameters in microgrid

In view of inverters line impedance and inverters parameters mismatch as well as local loads imbalance in microgrid,an improved real power-voltage ( PV) control strategy was proposed.Averaged output real power of all distributed generation ( DG) units was calculated,and then locally measured real power was subtracted to get power error.An integral term for real power error was added to regulate DG output voltage.With this integral control,the high accurate sharing of both real power and reactive power was achieved.The control strategy makes system have good stability and dynamic performance,which is suitable for complex microgrid structure.Even in the system with different capacity,accurate proportional load sharing among DGs can be obtained.Simulation and experimental results validate the correctness of the proposed strategy.