感应电动机惯性对电力系统低频振荡的影响

研究感应电动机惯性时间常数HD对电力系统低频振荡(LFO)的影响.在单机无穷大系统中运用积分流形理论对系统高阶状态方程进行降阶处理,以推导系统的振荡频率和阻尼比,从机理上就HD对低频振荡的影响进行定性分析.理论分析结果表明HD主要影响系统的低频振荡阻尼,影响趋势还与系统结构和初始运行状态有关.运用特征值分析方法分别对单机无穷大系统(SMIBS)和简单的两区域系统进行实例仿真,SMIBS仿真结果验证了理论分析.并且两区域系统的仿真结果表明了HD对系统区间振荡模式的影响.研究表明,在实际电力系统LFO分析中,等值感应电动机的惯性常数的选择非常重要.

The Influence of Induction Motor Inertia on Low Frequency Oscillation of Power System

The influence of inertia constant (H_D) of induction motor on low frequency oscillation (LFO) was studied.Integral manifolds theory was introduced to reduce the order of the system state equations in order to determine the oscillation frequency and the damping ratio in single-machine infinite bus system (SMIBS). The theoretical analysis shows that H_D influences mainly the damping of LFO, the extent of which is also associated with the system structure and initial operating condition. The eigenvalue analysis of SMIBS verifies the theoretical analysis of LFO local modes, and the result of a simple two-area system shows the influence of H_D on the inter-area oscillation modes of LFO. In summary, the appropriate H_D of equivalent induction motor in real power system is very important in the study of LFO.