Study on the oscillation characteristics of doubly-fed wind turbine considering the variation of operating parameters in microgrid
To study the coupling and oscillation characteristics of power equipment in microgrid,the energy functions of the wind turbine subsystem,generator and excitation subsystem in the doubly-fed wind turbine are deduced based on the transient energy flow method taking into account the wind speed and the control strategy of the unit.Then,the mechanism of the change of the energy consumption of each subsystem is investigated when the wind speed,the control parameters of the unit and other operational parameters change,and the oscillation characteristics of the unit are analyzed.Finally,the energy change and power oscillation characteristics of the doubly-fed wind turbine when the operation parameters change are analyzed by modeling and simulation on PSCAD/EMTDC platform,and the results are compared with the eigenvalue calculation results to verify the reasonableness of the analysis.At last,the influence mechanism of wind speed change on the oscillation of doubly-fed wind turbine is obtained.