一种自主降额运行的负荷虚拟同步机控制方法

A load virtual synchronous machine control method for autonomous derating operation

大量低惯量、欠阻尼的电力电子负荷接入电网影响电力系统的稳定性。文章针对DC/DC负荷,提出了一种前级采用负荷虚拟同步机,后级采用频率-输出电压下垂和电压电流闭环的控制策略;针对DC/AC负荷,提出了一种前级采用负荷虚拟同步机,后级采用频率-转速下垂和矢量控制系统的变频器控制方法。所提方法能够提高负荷在弱网下的适应能力,增强电力系统的稳定性。最后,通过Matlab验证了理论分析的正确性。

As a large number of power electronic loads are connected to the grid,the load side’s threat to the safety of the power system is increasingly prominent.Aiming at the DC/DC loads represented by electric vehicle charging pile,this paper proposes a control method of autonomous derating operation using the load virtual synchronous machine in the front stage,and the frequency and output voltage droop and voltage and current double closed loop in the latter stage.For the DC/AC load represented by synchronous motor,this paper proposes a frequency converter control method that uses the load virtual synchronous machine to control the front stage and the frequency-speed droop and vector control system in the latter stage.The load controlled by the proposed method not only improves its adaptability under the weak network,but also enhances the stability of the power system.Finally,the correctness of the proposed theory is verified on Matlab.