【作者】 郭钰锋； 于达仁； 赵婷；

【Author】 GUO Yufeng, YU Daren, ZHAO Ting (Harbin Institute of Technology, Harbin 150001, China)

【机构】 哈尔滨工业大学；

【摘要】 在电网运行的指标中,电网频率的概率分布一般被认为是正态分布,但实测的电网频率的概率分布并非如此。本文用随机信号分析的方法,研究了具有正态分布的随机信号通过几种非线性环节后的概率分布特性,从而对电网中非线性环节对电网频率概率分布的影响进行了研究。结果表明电网频率概率分布在调频死区的影响下呈现双峰现象,在限荷机组及加减负荷速率、供需平街的影响下出现偏态分布等。探讨了利用电网的频率分布特性图来估计电网中发电机组调频死区的大小,限速的程度等,并指出现有的基于正态分布特性制定出的相应指标是不符合实际的。更多还原

【Abstract】 Power system is a complicated system influenced by various factors, power system frequency is a important random variable in power system, its probability distribution is generally regarded as a normal distribution, but in fact it is not so. In this paper the probability distribution is discussed when Gaussian signal passing through nonlinear function. And then several factors influencing on power system frequency probability distribution are presented. It concludes that two peaks happens by the influence of dead-band, that inclined distribution happens by the influence of limit power units and the speed of increasing and decreasing power and the balance of supply and demand. This paper point out that some index based on Gaussian distribution of power system frequency is unpractical.更多还原