电力系统三相短路故障临界切除时间求解方法的在线应用  

Online Application of Solving Method for Critical Clearing Time of Three-Phase Short Circuit in Power System

作　　者：闫常友[1] 周孝信[1] 

机构地区：[1]中国电力科学研究院,北京市海淀区100192

出　　处：《电网技术》2009年第17期56-63,共8页Power System Technology

摘　　要：介绍了直接法的相关知识、单机无穷大系统模型和多机系统模型,详细讨论了PEBS方法的局限性。对单机无穷大母线系统进行了公式推导和仿真验证,从理论上探讨了多机系统的三相短路故障临界切除时间求解方法。重新定义了势能函数,对势能最大值的求解提出一些新建议,研究了系统的总动能和总势能,提出求解三相短路故障临界切除时间的新思路,完善了一些可能引起计算误差的技术细节。通过有代表性的真实故障算例验证了所提思路和方法的可行性。Based on the viewpoint of energy, the authors introduce the theoretical basis of direct method to calculate fault clearing time and describe single-machine infinite bus （SMIS） system model and multi-machine system （MMS） model, and analyze the limitation of potential energy boundary surface （PEBS） method in detail. The formulae for SMIS are derived and verified by case simulation, the solution of critical clearing time （CCT） of three-phase short fault in MMS is theoretically discussed. The potential energy function is redefined, and some suggestions on the solution of the maximum of potential energy are given; the total kinetic energy and potential energy of power system are researched and new thinking to solve the CCT of three-phase short fault is proposed, meanwhile, some problems that may cause calculation error are modified. The feasibility of the proposed thinking and method are verified by representative calculation examples of actual faults.

关 键 词：三相短路 临界切除时间 支路势能 

分 类 号：TM711[电气工程—电力系统及自动化]