新型交流励磁直驱风力发电机的空载特性

为解决现有双馈异步风力发电机低风速段运行范围窄和直驱永磁风力发电机励磁不可控的问题,提出一种新型的采用交流励磁的直驱式风力发电机.利用已经设计的发电机参数,推导新型直驱交流励磁风力发电机的数学模型,同时利用MATLAB的Simulink功能建立发电机空载模型.结果表明,励磁频率、定子频率及转子机械转速频率间存在线性关系;发电机机械转速在低风速段时,通过调节励磁频率和励磁电流,发电机仍能输出额定电压,最终增加了发电机的运行范围.

No-load characteristics of new AC excitation direct-drive wind generator

In order to solve the problems of both narrow operation range of doubly fed wind induction generator in lower wind velocity period and uncontrollable excitation of permanent magnetic direct drive wind generator, a new AC excitation direct drive wind generator was proposed. With the designed parameters for the generator, the mathematical model for new AC excitation direct drive wind generator was derived. Meanwhile, the no load model for the generator was established with the Simulink function in MATLAB. The results show that a linear relationship exists between the excitation frequency, stator frequency and mechanical rotational speed frequency of rotor. When the mechanical rotational speed of generator is in the low wind velocity period, the generator can still output the rated voltage though regulating the excitation frequency and excitation current, which finally extends the operation range of generator.