In this paper,the short-circuit current characteristics of inverter-interfaced distributed generations and the corresponding calculation method are studied. Firstly,through the actual short-circuit current waveform of an inverter, the characteristics of short-circuit current are discussed,and then the influence of control strategy on short-circuit cur?rent is analyzed. Accordingly,the short-circuit current is divided into sub-transient,transient and steady stages,and the characteristic in each stage is analyzed. The equivalent models of short-circuit in sub-transient and steady stages are also set up. Secondly,a phase-sequence hybrid general calculation method is put forward based on node-voltage equa?tion,which can be applied to the calculation of short-circuit current in the sub-transient and steady stages. Through a test example,the correctness of the proposed theory and method is verified.%该文针对逆变型分布式电源的短路电流特性及计算方法展开研究.首先通过逆变器实际的短路电流波形探讨了短路电流的特性,进而分析控制策略对短路电流的影响,将短路电流分为次暂态、暂态及稳态3个阶段,并对各阶段短路电流的特性进行了分析,建立了次暂态及稳态的短路等效模型.其次提出一种基于节点电压方程的相序混合通用计算方法,可适用于次暂态及稳态短路电流求解,通过算例测试验证了文中理论及算法的正确性.
展开▼
