提出了基于全参数空间的静态电压稳定域的2种切平面计算方法:特征向量法和隐函数求导法。2种方法均可考虑各种因素对于电压稳定域的影响。其中隐函数求导法还能够计算状态变量对于独立参数变量的偏导数。在此基础上,建立了从功率注入空间到线路传输功率空间的映射关系,可以解析求出割集功率空阎电压稳定域的超平面近似表达式,从而避免了现有数据拟合算法的局限性,提高了计算速度。此外,文中考虑电力系统运行限制对于电压稳定的影响,提出了实用电压稳定域的概念,并计算了相应的切平面。进一步在电压静态稳定域切平面分析的基础上,提出了3类电压稳定指标,有利于综合评估系统电压稳定水平。IEEE9和IEEE39节点系统的仿真分析表明,所提出的电压静态稳定域的切平面分析法可准确评估系统的电压稳定水平,为电力系统的安全运行提供了决策依据。
The algorithm of the static voltage stability region' s tangent plane through the characteristic vector method or the implicit function derivative method is presented in the total parameter space, which can provide quantitatively the influence degree of all kinds of parameters on the voltage stability region. The implicit function derivative method can calculate the partial derivative of state variables to independent parameter variables. Hyper-plane approximation in the cut-set space can be derived analytically based on the partial derivative through the mapping from power injection space to cut-set space, which can bypass the data fitting algorithm and improve the calculating speed. The practical voltage stability region' s tangent plane, which is formed by constraints of the power system, is also presented. Three kinds of voltage stability indices based on the tangent plane analysis method are presented to assess the voltage stability level comprehensively. Simulations of the IEEE 9-bus and IEEE 39-bus system show that the research on the static voltage stability region's tangent plane can assess the voltage stability level objectively and lay the foundation for correct decision-making for secure and stable operation of power systems.