功率因数可调的转子变频性能分析和研究

Analysis and Study on Power Factor Regulator Rotor-side Variable Frequency System

基于晶闸管有源逆变的串级调速给电网注入了大量谐波,造成了严重的电网污染,而且在停电时,还存在逆变颠覆故障。鉴于此,提出一种功率因数可调的新型转子变频调速系统,其后端采用电压型PWM整流器进行有源逆变,以有效控制无功功率,从而提高整个系统的功率因数。此外,还分析了其主电路中Boost单元,得出其升压特性不同于传统Boost,而是一个反向过程的结论。最后,通过实验验证了系统设计和模型的可行性。

When the conventional cascade speed drive system is taken to save energy,much harmonic and inactive power is injected to power system.Inverter failure also can not be avoided in power off.Based on these,a power factor regulator rotor-side variable frequency system is presented.Because of the PWM technology,the inactive power of feedback winding can be controlled easily,so the system power factor can be improved.At the same time,the circuit topology and principle are simply introduced and the conclusion that the boost characteristic in rotor-side variable frequency system is different from usual boost circuit is gotten.Finally,the correctness of system design and the feasibility of PWM model are verified by experimental results.