基于最速下降法的自适应环流抑制

Adaptive Circulation Suppression Based on Steepest Descent Method

针对交直流混合微电网孤岛运行时,并联变流器硬件参数不能完全一致,控制信号无法完全同步以及负荷波动导致并联回路中存在多种循环电流问题,提出一种基于最速下降法(SDM)的虚拟同步发电机(VSG)控制策略。通过最速下降法迭代得到循环电流最小时的变流器输出电压并反馈给VSG控制器,既实现各工况下VSG输出电压的同步,又有效地完成了负荷波动时的电压自适应调整。为了验证所提控制策略的有效性,在MATLAB/Simulink中搭建仿真模型,仿真结果表明所提控制方法可有效抑制系统环流。

During isolated operation of AC/DC hybrid microgrid,the hardware parameters of the shunt converter cannot be completely consistent,the control signals cannot be fully synchronized,and load fluctuations cause a variety of circulating current problems in the shunt circuit.According to these problems,a control strategy for virtual synchronous generator(VSG)based on the steepest descent method(SDM)is presented.The output voltage of the converter with the lowest cycle current is obtained through the steepest descent method and fed back to the VSG controller,which not only realizes the synchronization of the VSG output voltage under various working conditions,but also effectively completes the adaptive adjustment of voltage when the load fluctuates.In order to verify the effectiveness of the proposed control strategy,a simulation model is built in MATLAB/Simulink.The simulation results show that the proposed control method can effectively suppress the system circulation.