基于差动轮系调速的风力发电机的动力学建模与分析

Dynamic Modeling and Analysis of Wind Turbine Based on Differential Gear Train Speed Regulation

对基于无级调速原理的风力发电机动力学建模,改变传统风力发电机的齿轮箱传动比固定而采用电子方法实现变速恒频的特性,通过增加差动轮系的自由度,采用机械调速方式进行前端调速,使输出转速与转矩恒定,达到变速恒频的目的。以实现调速功能的差动轮系为主要研究对象,将整个风力发电机传动链简化成三个部分:行星架输入轴、太阳轮输出轴和齿圈调速轴,并运用拉格朗日方程和差动轮系转速约束关系,建立动力学方程。结合风力发电机并网要求,此外还研究了该情形下的动力学关系,将并网后的动力学问题即转化为:输出转速恒定条件时,可变的风轮转矩作用下,调速电机的调速问题。

Based on the principle of stepless speed regulation, dynamic modeling of wind turbine has been done. Having changed fixed transmission ratio characteristic of gearbox in traditional wind turbines and the variable speed constant frequency characteristic realized by electronic method, the freedom of differential gear train is increased and the mechanical means have been used for the fore-end speed regulation in order to achieve constant output speed and torque. Taking the diffe-rential gear train as the main learning object, in this paper the wind turbine transmission chain is divided into three parts: planet carrier input shaft, sun wheel output shaft and ring gear speed- regulation shaft, and dynamic equations are established using the Lagrange equation and the speed constraint relations of differential gear train. Therefore, to satisfy the grid-connected requirement, the dynamic relationship in this circumstance is also learned. The dynamic problem can be transformed into the speed-regulation problem of speed-regulation motor under the variable wind turbine torque to achieve constant output speed.