级联H桥SVG直流侧电容电压平衡控制方法  

A Balancing Control Method of DC Capacitor Voltage for Cascaded H-Bridge SVG

作　　者：田铭兴[1] 阎宏[1] 赵雨欣[1] 

机构地区：[1]兰州交通大学自动化与电气工程学院,甘肃省兰州市730070

出　　处：《电网技术》2013年第9期2632-2638,共7页Power System Technology

基　　金：国家自然科学基金项目(51167009)~~

摘　　要：直流侧各模块电容电压的稳定控制是保证级联H桥静止无功发生器(static var generator,SVG)正常运行的重要条件。推导了级联H桥SVG与电网交换的有功功率数学模型,得出了相间与相内各模块吸收有功功率的关系,总结了相内各模块直流侧电容电压不均衡的原因。为解决由脉冲延时造成的级联H桥SVG直流侧电容电压不平衡,提出了在全局调制信号的基础上叠加一个与补偿电流同向的有功电压来动态调节各模块有功功率的方法,并运用有功–无功解耦全局控制策略保证SVG设备实时无功补偿。仿真结果验证了所提方法的有效性。The stable control of capacitor voltages of all modules at DC side is an important condition to ensure normal operation of cascaded H-Bridge static vat generator （SVG）. The mathematical model of active power exchanged between cascaded H-bridge SVG and power grid is derived and the relation of the active power absorbed among phases and the active power absorbed by modules in a phase is obtained, and the reasons causing imbalance among capacitor voltages at DC side of modules in a phase are summarized. In allusion to capacitor voltage imbalance at DC side of cascaded H-bridge SVG, which is caused by pulse delay, a method to dynamically adjust the active power of each module is put forward, that is, an active voltage in the same direction with the compensating current is superimposed to global modulation signal, and the real-time compensation of reactive power by SVG is ensured by applying global control strategy with active-reactive power decoupling. Simulation results validate the effectiveness of the proposed method.

关 键 词：静止无功发生器 级联H桥 电容电压平衡控制 载波移相 

分 类 号：TM721[电气工程—电力系统及自动化]