虚拟同步控制构网型双馈风电机组功角振荡量化分析及抑制OA

Virtual synchronous generator(VSG)controlled grid-forming doubly-fed wind turbines exhibit inertia and damping characteristics similar to synchronous generators,and their synchronization processes rely on multi-level loop coupling effects,but are susceptible to active power-angle oscillations and associated stability risks.Therefore,an active power-angle transfer function for VSG-controlled grid-forming doubly-fed wind turbines considering multiple control loops is first established,and the instability mechanism of weakly damped active power-angle oscillations caused by multi-level loop coupling is revealed.Then,the influence and variation laws of key control parameters,including the power-synchronization loop and the voltage control loop,on the system dynamic performance are quantified based on the root-locus analysis,and the corresponding parameter stability region is described.On this basis,an active suppression method for active power-angle oscillations based on frequency damping is proposed.By feeding the virtual speed signal into the virtual synchronous angle,it enhances the power-angle response and tracking speed,avoids transient underdamping caused by response lag,expands the parameter stability domain,and improves the stable operation capability of grid-forming doubly-fed wind turbines in complex-disturbance scenarios.Finally,based on the time-domain and controller hardware-in-the-loop simulation of a grid-connected system with 2.5 MW grid-forming doubly-fed wind turbines,the accuracy and effectiveness of the theoretical analysis and the power-angle oscillation suppression strategy are jointly verified.