非解析复变电力系统电压稳定的动态分析方法

Comprehensive Dynamic Analysis Method for Power System Static Voltage Stability

由于电力系统是非解析复变系统,节点电压不是负荷电流的解析复变函数。在复数域内,节点电压不能直接对负荷电流求导,所以尚没有文献应用动态分析方法研究电力系统的电压稳定性。提出非解析复变电力系统的动态分析方法,定义电力系统综合动态等值阻抗,证明电力系统达到极大传输功率的必要条件是系统综合动态等值阻抗模等于负荷静态等值阻抗模。仿真计算表明:电力系统极大传输功率的必要条件是正确的;阻抗模裕度最小值决定系统电压稳定整体水平,重点监控最小阻抗模裕度节点的电压稳定水平最有价值。动态分析方法为进一步建立电力系统非线性等值模型及应用非线性等值模型快速准确计算极限潮流提供了理论基础。电力系统极大传输功率判据也可用于判断大规模电力系统潮流解是否可行。

As power system is a non-analytical complex variable system, node voltages are not analytical complex-variable function of load current. In the plural domain, node voltages are not directly derivative of the load current, so there are still no papers using dynamic analytic method to study power system voltage Stability. In this paper, the dynamic analytic method of non-analytical complex was derived; the comprehensive dynamic equivalent impedance of power system was defined; and the necessary condition when power system achieves limit transmission is that the comprehensive dynamic equivalence impedance mode is equal to load static equivalent impedance mode. By simulation and calculations, it proved that the necessary condition was right; load impedance modulus margin can accurately describe the system load node voltage stability level. Dynamic analytic method set a theoretical foundation to establish power system nonlinear equivalent model, and to apply nonlinear equivalent model to calculate limit power quickly and accurately. The maximum transmission power judgment criterion can be used to judge whether it is feasible to the solution of power flow equation for large-scale power system.