基于无功补偿下的风电机组并网对暂态电压的稳定性分析

Stability Analysis of Transient Voltage of Wind Turbine Connected with Network Based on Reactive Power Compensation

为了提高风电机组在并网后暂态电压的稳定性,本文主要以6个1.5 MV的双馈风力发电机构成的风力发电机组为研究对象,研究风电机组并网后在不同风速下以及三相短路故障发生时对风电机组并网后暂态电压的影响。当风电机组并网后出现暂态电压不平衡的状态时,通过添加电容无功补偿装置和STATCOM无功补偿装置可对电网电压出现暂态不平衡状态进行无功补偿。在MATALAB/Simulink下进行建模和仿真可知,当添加STATCOM无功补偿装置后,它能够使风电机组并网后的暂态电压恢复到稳定的状态;然而电容无功补偿则不能完全达到这种效果。因此,为了保证风力发电机组并网后系统暂态电压的稳定性,使并网系统能够在受到扰动后很快恢复稳定状态,必须添加STATCOM无功补偿装置。

In order to improve the stability of transient voltage of wind turbines after grid connection,this paper mainly studies the wind turbines composed of six 1.5MV doubly-fed wind turbines,and studies the wind turbines at different wind speeds after grid connection.The influence of the three-phase short-circuit fault on the transient voltage after the wind turbine is connected to the grid.When the transient voltage imbalance occurs after the wind turbine is connected to the grid,the reactive power compensation device and the STATCOM reactive power compensation device can be used to compensate the transient imbalance of the grid voltage.Modeling and simulation under MATALAB/Simulink shows that when the STATCOM reactive power compensation device is added,it can restore the transient voltage after the wind turbine is connected to the grid to a stable state;however,the reactive power compensation cannot fully achieve this.effect.Therefore,in order to ensure the stability of the transient voltage of the wind turbine after the grid connection,the grid-connected system can restore the steady state quickly after being disturbed,and the STATCOM reactive power compensation device must be added.