摘要
直流侧电容电压的不平衡及其控制是链式STATCOM要解决的关键问题。笔者给出了链式STATCOM直流电容稳态数学模型,分析了逆变桥参数对电容电压不平衡的影响,指出开关脉冲延时不同、混合型损耗差异以及并联型损耗差异是造成电容电压不平衡的主要原因。结合十一电平STATCOM,提出采用基频开关法投和基频脉冲循环换位法可以有效的保持链式STATCOM直流电容电压的平衡稳定,STATCOM的PSCAD模型及其仿真验证了该方法的可行性和有效性。
The control of voltage balance of DC capacitors is very important for reliable operation of cascade STATCOM. The impact of inverter parameters on the capacitors＇ voltage distribution is investigated based on the proposed static mathematical model of cascade STATCOM DC capacitors, and the result shows that different switching loss, parallel loss, and time delay of gate pulse are the main causes of voltage unbalance. For a 11-level cascade STATCOM, fundamental frequency switching and pulse cycle transposition methods are proposed to keep the voltage balance of DC capacitors. Simulation of the PSCAD model of STATCOM verifies the feasibility and effectiveness of the proposed methods.
出处
《高压电器》
CAS
CSCD
北大核心
2010年第4期10-15,共6页
High Voltage Apparatus
基金
江苏大学高级人才专项基金(07JDG036)
江苏省工业攻关项目(BE2007069)
关键词
静止同步补偿器
链式STATCOM
电容电压不平衡
基频开关法
基频脉冲循环换位法
sctatic synchronous compensator（STATCOM）
cascade multilevel inverter
DC capacitor voltage unbalance
fundamental frequency switching（FFS）
pulse cycle transposition
