Aiming at the active power oscillation problem generated when the virtual synchronous genera-tor(VSG)is operated in parallel,the mechanism of active power oscillation was analyzed by establishing a small-signal model of the dual VSG system,and a transient power equalization strategy based on the im-proved virtual impedance and a power oscillation suppression strategy based on the power differential term with adaptive inertia and damping were proposed to realize the combination of the active power differential term with angular acceleration to achieve the adaptive regulation of inertia,while the active power differ-ential term was introduced into the damping control link to replace the conventional damping term to real-ize the adaptive regulation of damping.The proposed strategy can make the angular frequency difference between the VSGs converge to zero more quickly during the dynamic time,so as to reduce the overshoot of the active power oscillation and improve the frequency dynamic response performance.A simulation model of VSGs connected in parallel was constructed,and the simulation results show that the proposed improved control strategy can realize active equalization in transient state,reduce the overshoot of active power oscillation by 41%and the oscillation process by 1 second in dynamic state.
维普
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