基于子空间法的电网暂态频率扰动惯量估计

针对暂态频率扰动下传统惯量估计方法受扰动发生时刻和惯性响应持续时间判断敏感而导致估计误差偏大的问题,文章提出基于子空间法的电网惯量估计思想。通过分析暂态频率扰动发生前、惯性响应及一次调频响应各阶段的电网频率响应模型的冲激响应特征,获得各阶段的电网惯量统一性表达,并将各阶段电网频率响应模型作为相同待估计系统,应用子空间法进行系统模型参数辨识,最终估计出电网惯量。通过算例分析验证了文章方法对电网惯量估计的有效性及精确性。

Power System Inertia Estimation Based on Subspace Method Under Transient Frequency Disturbance

In order to solve the problem that traditional inertia estimation method under transient frequency disturbance is sensitive to the judgment of disturbance occurrence and inertial response duration, which leads to large estimation error, this paper proposes the idea of grid inertia estimation based on subspace method. By analyzing impulse response characteristics of the grid frequency response model at stages before transient frequency disturbance, inertial response and primary frequency-regulation response, the unified expression of grid inertia at each stage is obtained, and the grid frequency response model at all stages are taken as a system to be estimated. Subspace method is used to identify the parameters of the system model, and finally grid inertia is estimated. The effectiveness and accuracy of this method are verified by simulation.