广东电网动态负荷实测建模及模型有效性的研究

MEASUREMENT-BASED DYNAMIC LOAD MODELING AND MODEL VALIDATION ON GUANGDONG GRID

该文给出了基于测量的负荷动特性建模的数据来源 :在变电站安装装置 ,等待扰动发生时记录电压电流和频率 ;建模原则 :建立负荷特性这个随机过程的外特性模型 ,用尽量简单的模型描述出多个数据样本的共性 ,即具有统计规律的负荷动特性 ;模型的数学表达为解耦二阶差分方程 ;并结合实测得到的数据 ,建立了某地区负荷动特性模型。将此模型用于某送出系统发电机摇摆和其他地区故障电流和功角摇摆仿真中 ,将仿真结果与现场记录的数据进行比较 ,比较结果表明实测建立的动态模型在短路电流计算中得到的结果比BPA静特性模型更接近实际 ,在功角摇摆仿真中两种模型得到的结果相当接近 ,实测动态模型比BPA静态模型计算出的截面功率极限提高了 5 %。

This paper gives a measurement based load modeling method.A measurement instrument was installed in load substation and waiting for the disturbances,during which the instrument started to record voltages and currents.Load characteristics are considered as a stochastic process.The goal of dynamic load modeling is to describe the stochastic character with a model as simple as possible.Uncoupled difference equations of second order are proposed as mathematical model.With the data measured from some grid,dynamic load models were obtained. The models were used in simulating generators phase swing and in fault current simulations for their validation.The simulation results show that short circuit currents simulated by the dynamic load models are more closed to real currents measured from the grid than that simulated by the static load models from BPA program.As for generator phase swing,the results simulated by both of models are closed to each other.The limited transmission power simulated by the dynamic load models is 5% higher than that simulated by the static load models.