定子双绕组感应电机风力发电系统励磁电容的优化选取

在定子双绕组感应电机(DWIG)风力发电系统中,励磁电容的优化选取对控制绕组励磁变换器(SEC)容量的最小化具有重要作用,它不仅与发电机参数、转速范围有很大关系,同时还受风力机功率曲线和负载性质的影响。本文以SEC容量最小化为目标,在分析该发电机励磁无功变化规律的基础上,研究了励磁电容优化选取的原则,采用图解法和迭代法得到带阻性负载下的优化励磁电容值。考虑到整流负载的非线性因素,利用仿真法对该值进行合理调整,最终得到带整流负载所需的优化励磁电容值。在一台18kW带整流负载的DWIG样机系统上进行了实验验证,结果表明,系统在宽转速范围内能稳定运行,励磁变换器容量约为额定输出功率的1/3,实现了励磁变换器容量最小化。

Optimal Selection of Excitation Capacitor for Dual Stator-Winding Induction Generator Wind Power System

In the dual stator-winding induction generator(DWIG) wind power system,the optimal selection of excitation capacitor is very important for minimizing the capacity of static excitation controller(SEC).The optimal excitation capacitor is not only related to the generator parameters and speed range,but also affected by the wind turbine power curve and the types of load.Based on the analysis of the change of excitation reactive power in DWIG,the optimal rule of excitation capacitor is investigated to minimize the capacity of SEC.The graphic and iterative methods are employed to achieve the optimal excitation capacitor with the resistance load.Considering the nonlinear influence of rectifier load,this capacitor is modified properly by simulation.Experiments are carried on the prototype of 18kW DWIG system with the rectifier load.The results illustrate that the system has good performance over a wide speed range,and the capacity of SEC accounts for about one third of the rated power.The implementation of minimizing the capacity of SEC is obtained.