【摘要】 为研究风力机功率在风电机组中传播、变换时与风电机组各环节的耦合关系及机组输出功率振荡特性，以双馈风电机组为例，首先计及塔影效应和风剪切、风速大小，推导各子系统的能量函数；考虑机组阻尼及风速变化，分析各子系统能量变化及机组输出功率的振荡特性；最后，在PSCAD/EMTDC上建模仿真，通过能量变化深入分析风力机功率在机组内传播机理及功率振荡特性。仿真结果表明：含低频振荡分量的风力机功率通过负阻尼双馈风电机组时，与机组的次同步振荡耦合，风力机子系统、发电机及励磁子系统输出能量大幅增加，机组输出功率中既有低频振荡也有次同步振荡，它们随机组阻尼和风速变化而变化；风速变化时双馈风电机组消耗的能量主要由风力机子系统决定。更多还原

【Abstract】 In order to study the coupling between the wind turbine power and each link of the unit and the influence on the output power of the unit,a double-fed wind turbine is used as an example,Firstly,the energy functions of each subsystem are derived taking into account the tower shadow effect,wind shear and wind speed. Then,the energy variation of each subsystem and the oscillation characteristics of the unit output power are analyzed considering the damping of the turbine and wind speed variation. Finally,the power propagation mechanism and power oscillation characteristics of wind turbine are analyzed through energy changes on the PSCAD/EMTDC platform. The simulation results show that the energy of each subsystem increases greatly when the low frequency oscillation power of the turbine passes through the negatively damped DFIG. The output power of the turbine contains low frequency oscillation and sub-synchronous oscillation,and the amplitude and frequency of oscillation vary with wind speed and damping of the turbine. The energy consumed by the DFIG is mainly determined by the wind turbine subsystem when the wind speed changes.更多还原