基于逆变型电源暂态电流回代的系统级故障暂态解析

随着高比例电力电子设备和高比例新能源的接入,未来电力系统需要全时域量保护以应对系统复杂的故障特征.系统级故障暂态分析作为时域量保护的研究基础具有重要意义.鉴于逆变型电源(IIG)的受控特性,系统级故障暂态解析需应对机组输出电流的动态相位换算和多机系统方程高阶求解2个挑战.文中提出一种基于IIG暂态电流回代的系统级故障暂...

Transient Analysis of System-level Fault Based on Transient Current Back-substitution of Inverter Interfaced Generator

With the integration of high proportion of power electronic equipment and renewable energy,the future power system needs time-domain protection to deal with the complex fault characteristics of the system.System-level fault transient analysis is of great significance as the research basis of time-domain protection.In view of the controlled characteristics of inverter-interfaced generator(IIG),system-level fault transient analysis needs to deal with two challenges:dynamic phase conversion of output current of generation units and solving of high-order multi-generation system equations.A transient analysis method of system-level fault based on transient current back-substitution of IIG is proposed in this paper.By analyzing the dynamic relationship between the output power of generation unit and the terminal voltage phase,the dynamic phase conversion of IIG transient current to unified reference system is realized.The system equation is modified transiently to avoid high-order operation.On this basis,the transient voltage of the network nodes can be solved linearly by the transient current of each generation unit,and the time-domain accurate solution for the transient currents at the fault point and the whole network can be obtained.Simulation results show that the proposed method can achieve more accurate system-level fault transient analysis.