At present,the direct drive permanent magnet synchronous generator(DD-PMSG)grid connected system based on virtual synchronous generator(VSG)control will experience power oscillation at sub synchronous frequencies.The ...At present,the direct drive permanent magnet synchronous generator(DD-PMSG)grid connected system based on virtual synchronous generator(VSG)control will experience power oscillation at sub synchronous frequencies.The mechanism and characteristics of this new type of sub-synchronous interaction(SSI)are not yet clear,and the system cannot recover to steady state solely based on the characteristics of VSG itself.Especially when connected to a weak current network,oscillations are more pronounced,affecting the stability of the system.In severe cases,the systemmay trigger shutdown protection and be disconnected from the network.Existing research has only analyzed the oscillation mechanism under this phenomenon and has not proposed corresponding control strategies.This article proposes aVSM control strategy based on the VSG control algorithm,which balances the dq axis component of voltage and current,and improves the voltage and current loop of VSG control to reduce the impact of sub-synchronous oscillation(SSO)on the power grid.In MATLAB/Simulink,a simulation model of the proposed control strategy was built to verify its correctness and effectiveness.展开更多
文摘At present,the direct drive permanent magnet synchronous generator(DD-PMSG)grid connected system based on virtual synchronous generator(VSG)control will experience power oscillation at sub synchronous frequencies.The mechanism and characteristics of this new type of sub-synchronous interaction(SSI)are not yet clear,and the system cannot recover to steady state solely based on the characteristics of VSG itself.Especially when connected to a weak current network,oscillations are more pronounced,affecting the stability of the system.In severe cases,the systemmay trigger shutdown protection and be disconnected from the network.Existing research has only analyzed the oscillation mechanism under this phenomenon and has not proposed corresponding control strategies.This article proposes aVSM control strategy based on the VSG control algorithm,which balances the dq axis component of voltage and current,and improves the voltage and current loop of VSG control to reduce the impact of sub-synchronous oscillation(SSO)on the power grid.In MATLAB/Simulink,a simulation model of the proposed control strategy was built to verify its correctness and effectiveness.