割集功率空间上静态电压稳定域的实用边界

Practical Boundary of Static Voltage Stability Region in Cut-set Power Space of Power Systems

提出了电力系统在割集功率空间上静态电压稳定域边界的实用表达方法。用临界割集将系统分为地理上互不连通的两部分,即相对集中的弱节点区域和非弱节点区域,利用连续潮流,搜索大量的电压稳定临界点,以临界割集上线路的有功和无功潮流为坐标,并通过最小二乘法,将获得的临界点以超平面的形式拟合出电压稳定域的边界,其误差可满足工程应用的要求。这种方法既达到了使复杂电力系统降维的目的,又方便了运行人员监视系统稳定性。同时,电压稳定域边界以超平面形式表示,为电力系统的在线安全分析、评估和优化提供了简明、方便的解析工具。该方法在IEEE 14节点、IEEE 39节点、IEEE 118节点等系统和EPRI 1000节点系统的算例中得到了很好的验证,均以较小误差满足工程需要。

A method to approximate the boundaries of static voltage stability region (SVSR) m cut-set power space of electrical power systems is presented. Firstly, a critical cut-set in the sense of voltage stability divides the system into two separate parts, i.e. concentrated weak-node region and non weak-node region. Then with the active and reactive power flow in the branches of a critical cut-set as coordinates, the boundary of SVSR in cut-set power space is obtained by fitting lots of critical points searched by continuous power flow (CPF) with a hyper-plane through the least-square approach. This method not only gives an efficient way to reduce the power system dimensions, but also is convenient for operators to monitor power systems security. The hyper-plane which describes the boundary of SVSR in cut-set power space makes it very useful in analyzing, assessing and optimizing power system security. Examples on various IEEE test systems and EPR! 1000 power system show that this method can approximate the SVSR boundaries with a satisfied accuracy.