中文摘要：

频率是电力系统的重要电气量，频率偏移的根本原因是有功功率不平衡。分析传统频率响应分析模型，如全状态分析法、平均系统频率模型和系统频率响应模型等的优缺点，提出一种新的基于直流潮流的电力系统频率响应分析方法。该方法忽略无功-电压变化对有功-频率动态的影响，假定发电机端电压恒定，对发电机组模型进行适当简化，并采用直流潮流近似考虑删络影响。仿真分析结果表明，该方法能较好地反映系统有功-频率动态过程，具有较高分析精度和较小计算量，能同时给出系统在功率扰动下的频率动态信息和有功动态信息，可用于功率扰动事故的快速频率响应分析和预想事故筛选。

英文摘要：

Frequency is a crucial index in the power system The essential cause of frequency deviation is the imbalance of active power. Conventional frequency response analysis methods, e.g. full-state analysis, average system frequency model （ASF） and system frequency response model （SFR）, are summarized, and a new direct-current-loadflow-based power system frequency response analysis method （DFR） is proposed. The DFR model neglects the dynamic impact imposed by reactive power-voltage on active power-frequency response. It is presumed that terminal voltages are constant. The dynamic models of generating units are simplified properly. Direct current loadflow is utilized to consider the influence of the network approximately. Simulation results of two test systems show thai the DFR model can reflect the dynamics of active power-frequency with high accuracy and less computation load. The DFR model can provide the dynamic information of frequency and that of active power. It can be used for the fast frequency response analysis and contingency screening of the active power perturbation.