逆变型分布式电源的灵活正负序电流控制方法与等值序网模型

逆变型分布式电源的控制方法对电网有显著影响,但现有方法难以兼顾逆变型分布式电源在故障穿越、继电保护以及故障分析等方面的要求。提出了一种逆变型分布式电源的灵活正负序电流控制方法,在电网发生不对称故障时向电网中注入正序和负序无功电流。在此基础上建立了逆变型分布式电源在故障状态下的等值序网模型。仿真结果表明,所提方法能够增强逆变型分布式电源的故障穿越能力,在电网发生不对称故障时保留电流的序分量特征。

Flexible positive and negative sequence current control strategy and equivalent sequence network model of inverter interfaced distributed generation

The Inverter Interfaced Distributed Generation (IIDG) control strategy affects the power system significantly. However, the current strategies are difficult to take into account the requirements of fault ride-through, relay protection, and fault analysis. This paper proposes a flexible positive and negative sequence current control strategy of IIDG to inject positive and negative sequence reactive current into the grid under asymmetrical fault conditions. Based on this strategy, the equivalent sequence network model of IIDG is proposed. Simulation results show that the proposed strategy can improve the fault ride-through capability of IIDG, and can keep the sequence component characteristics of fault current under asymmetrical fault conditions. This work is supported by National Key Research and Development Program of China (No. 2017YFB0903201).