【摘要】 准确界定负荷稳定与电压稳定的关系对于完善电力系统电压稳定理论基础有重要意义。利用非线性动力系统稳定理论,定义了负荷稳定,发现负荷失稳的有限性,即在负荷失稳后,负荷等值导纳模值只能在有限的范围内变化。研究了电压稳定问题的本质属性,认为电压稳定性应属于输出变量有界性问题。用戴维南等值定理分析了负荷稳定与电压稳定的关系。结果表明:负荷失稳的有界性决定了电力系统负荷稳定性不能等同于电压稳定性,负荷失稳不是电压失稳的充分条件;电力系统电压稳定性的本质属性决定了电压稳定性不仅与负荷稳定有关,而且与系统各元件和控制装置对电压的支持力度有关。对典型测试系统的仿真,证实了研究结果的正确性。更多还原

【Abstract】 It is important for improving the theoretical basis of power system voltage stability to demarcate the load stability and voltage stability. Based on the non-linear dynamical system stability theory,the load stability is defined and the boundedness of load instability is found,i.e.,after load instability,the equivalent admittance module only changes within limited range. The essential attribute of voltage stability is studied,and it is proposed that the voltage stability belongs to the problem of output variable boundedness. The relationship between the load stability and voltage stability is analyzed by using Thevenin theorem. The results indicate that the load stability is not equal to the voltage stability and the load instability is not the sufficient condition for the voltage instability determined by the boundedness of load instability. According to the essential attribute of voltage stability,the voltage stability not only relates to the load stability,but also relates to the ability of maintaining voltage of elements and control devices of power system. Simulation results of a typical testing system confirm the validity of the conclusions.更多还原