摘要
通常情况下由于各种原因三相电网电压是不完全平衡的.这就使得常规的PWM整流器整流效率较低,为了提高电网不平衡条件下PWM整流器的整流效率,本文讨论了一种在电网不平衡条件下PWM整流的控制方法,在分析不平衡电网数学模型的基础上,建立了正、负序双电流控制策略的数学模型,利用Simplorer7.0对系统进行了仿真,通过对不平衡条件下常规的PWM整流器和不平衡条件下正、负序双电流控制的仿真结果进行对比,表明正、负序双电流控制可以提高网侧功率因数,改善系统的动态性能,同时得到较平稳的整流输出电压,有利于提高系统整体的运行效率。
For various reasons the Three-phase grid voltage is unbalanced which lead the PWM recetifier to low factor.In order to inprove the PWM recetifier factor under unbalanced input voltage,One method is proposed,In this way the thesis researces the work principle of PWM converter deeply starts from the reason and characteristics of the asymmetry power system and found the dual current control scheme for PWM rectifier under unbalanced conditions simulationmodel using SIMPLORER Simulation Center 7.0,Compare with the old PWM recetifier it is proved that this method can improve the PWM recetifier factor,obtain quickly following performance and it is better in restraining DC voltage.Above all this method can reduce enery loss.
出处
《变频器世界》
2010年第7期57-59,64,共4页
The World of Inverters
关键词
PWM整流器
不平衡电网
功率因数
动态性能
PWM recetifier
Unbalanced input voltage
Power factor
Dynamic performance
