不同旋转备用容量下电网频率稳定特性研究

Research on Frequency Stability Characteristics of Power Grid Under Different Spinning Reserve Capacity

随着多条特高压直流线路的投运,受端电网的发电容量随开机数目的减少而快速降低,随之而来的是一次调频的备用容量减少,从而导致受端电网的频率稳定控制愈加艰难。为了反映不同旋转备用的频率特性引入旋转备用容量占可用容量比值这一参数,提出改进的SFR模型。使用模型分别对系统高频和低频稳定进行分析,得出拥有旋转备用的电力系统对发生掉机故障的承载能力优于无旋转备用的电力系统。在系统机组出力相同时,可以通过提高系统旋转备用来提升系统的低频稳定性。最后通过算例仿真验证了所提旋转备用容量优化配置方案的有效性。

With the operation of several ultra-high voltage DC lines,the generating capacity of the receiving end grid decreases rapidly as the number of start-ups decreases,followed by a reduction of the reserve capacity of the primary frequency modulation,which makes the frequency stability control of the receiving end power grid more difficult.In order to reflect the frequency characteristics of different spinning reserves and introduce the ratio of spinning reserve capacity to available capacity,an improved SFR model was proposed.The model was used to analyze the high-frequency and low-frequency stability of the power system,and it was concluded that the power system with spinning reserve was better than the power system without spinning reserve.When the output of the system units was the same,the low frequency stability of the system can be improved by increasing the system spinning reserve.Finally,a calculation example was used to verify the effectiveness of the proposed optimal allocation scheme of spinning reserve capacity.