鼠笼型全功率风电变换器控制策略研究与实验

摘要

全功率风电机组的发电机定子侧通过双PWM变换器接入电网,相比双馈型发电机组具有更好的抗电网电压波动能力.在低电压穿越过程中发电机和机侧变换器几乎不受电网电压变化的影响,因此低电压穿越控制策略相对双馈型发电机组而言较简单,且更易于实现.机组并网输入有功功率和无功功率控制主要在网侧变换器中实现,无功功率调节简单方便,可实现任意功率因数运行.在分析异步发电机和PWM整流器数学模型及控制策略的基础上,在实验室搭建了一套鼠笼型异步全功率的风电实验平台进行实验验证.实验结果表明,采用该控制策略能够控制异步发电机的平稳发电运行,具有并网过渡时间短,并网电流冲击小等优点.%Since stator winding connected to the grid through the dual PWM converters,the full-scale power wind turbine has better ability to resist grid voltage perturbation and easier low voltage ride through control method to implement than double-fed wind turbine.The combined grid active and reactive power control are realized in the grid-side converter,the reactive power control is quite simple and the arbitrary power factor can be acquired easily.The mathematical models and the control theories of the asynchronous induction motor and the PWM rectifier are presented.The squirrel-cage induction motor full-scale wind power platform is built and relevant experiments are performed.The resuits show that the presented control strategy can control the generator operation smoothly and has merits of short time and small flashing current in the course of combing gird process.