基于误差溯源的风电场等值模型参数校验方法研究

Parameter calibration of wind farm equivalent model based on error tracing

随着大规模风电场接入电力系统,定期对风电场模型参数进行校验是准确开展大电网安全稳定分析的前提和保障。在风电场模型参数校验过程中,如何实现模型的误差溯源,挑选出偏离其真实值而需要进行校验的问题参数是一个亟需解决的问题。与此同时,现有方法通常采用多台等值风机对风电场进行简化建模。相比于传统火电机组,大型风电场等值模型的参数个数显著增加,同时对多台等值风机的参数进行误差溯源和辨识是一项困难的工作。为此,建立了一种基于误差溯源的风电场等值模型参数校验方法。首先基于混合动态仿真技术,将各等值风机的外部系统简化为一个可变阻抗,实现各等值风机参数的分步校验。其次,理论证明了问题参数轨迹灵敏度曲线和模型输出误差曲线具有相似的频谱能量分布,并基于此提出了一种问题参数筛选方法。最后,基于扩展卡尔曼滤波算法对所选出的问题参数进行辨识。在改进后的IEEE 39节点标准系统中验证了所提方法的准确性。

With the integration of large-scale wind farms(WFs),regular calibration of WF model parameters is a prerequisite and guarantee for accurately carrying out security and stability analysis of the power grid.In parameter calibration of WF model,how to realize the error tracing of the model and select the problematic parameters,that deviate from their true values and need to be calibrated,is an urgent problem.At the same time,existing methods usually use multiple equivalent wind turbines for simplified modeling of WFs.Compared with the traditional thermal turbines,the number of parameters in the equivalent model increases significantly,and it is a difficult task to trace and identify the errors in the model parameters of multiple equivalent wind turbines at the same time.For this reason,this paper proposed a WF parameter calibration method based on error tracing.Firstly,based on the hybrid dynamic simulation technology,the external system of each equivalent wind turbine is simplified into a variable impedance to realize the step-by-step calibration of each equivalent wind turbine.Secondly,it is theoretically proved that the trajectory sensitivity curves of problematic parameter and the model output error curves have similar spectral energy distributions,and a problematic parameter screening method is proposed.Finally,the selected problematic parameters are identified based on the extended Kalman filter algorithm.The accuracy of the proposed method is verified in the improved IEEE 39-node standard system.