基于不对称多电平逆变器的无功补偿器的实现

Realization of STATCOM Based on Asymmetrical Multi-level Inverter

随着多电平技术的发展,以多电平逆变器为主电路的静止同步补偿器(STATCOM)显示出其优越性。为了对目前应用的STATCOM进行改进,提出将不对称3H桥多电平逆变器拓扑应用到STATCOM的主电路中,分析了其工作原理。针对无功补偿,研究了不对称3H桥的分段载波层叠脉宽调制(PWM)控制方法,实现了输出谐波含量少的电压波形。完成了不对称3H桥多电平STATCOM的硬、软件设计,制作了单相STATCOM的原理样机,进行了无功补偿实验。结果表明,设计的STATCOM样机能有效补偿系统中的无功功率,并保证电流波形的质量,具有良好的补偿效果,与传统结构的STATCOM相比,在输出波形质量方面体现出多电平的优势。

With the development of multi-level technology, the STATCOM containing multi-level inverter shows its su- periority, in order to improve current STATCOM, the asymmetric 3H multi-level inverter is proposed as the main cir- cuit topology of STATCOM.The operation principle of asymmetric 3H inverter has been analyzed.Carrier wave dispo- sition method of part pulse width modulation（PWM） on asymmetric 3H inverter has been analyzed for reactive power compensation.Asymmetric 3H inverter has a good output voltage waveform with this control method.The hardware and software of the STATCOM based on the asymmetric 3H multi-level inverter have been designed.An experimental pro- totype has been made.Reactive power compensation experiments have been done.The results show that the experi- mental prototype of the STATCOM can be effective in compensating for the reactive power in the system, ensures the quality of the current waveform and have a good compensation effect.Compared with the traditional structure of STAT- COM, the quality of the output waveform reflects the advantages of multi-level.