摘要
模块化多电平变流器(MMC)子模块电容电压的平衡与否严重影响STATCOM对电网无功的补偿效果。文中针对传统PI控制器无法抑制环流对均压效果的影响,根据能量均分原则和电压均衡原则,使用PIR控制器对环流实现无静差调节。首先通过平衡控制器产生对应于每个子模块的参考电压,并结合载波移相调制策略(CPS-SPWM)来修正MMC每个子模块开关器件的调制波,确保各子模块的电容电压维持在一个较小的动态波动范围内,最终使STATCOM对系统具有较好的无功补偿效果。最后,运用MATLAB/SIMULINK仿真软件验证了所提策略具有较好的均压效果。
The balance of capacitor voltage of the sub-module of modular multilevel converter （MMC） has a serious impact on the compensation effect of STATCOM on the reactive power of the power grid. Aiming at the traditional PI controller can＇t restrain the effect of circulating current on the voltage balance control, a PIR controller is used to achieve the adjustment of circulating current without steady state error according to the principle of equipartition of energy and the principle of voltage balance. Combined with the characteristics of carrier phase shift modulation strategy （ CPS- SPWM）, a reference voltage corresponding to each sub-module＂ is generated by the balance controller to revise the MMC modulation wave in each module switching devices. This scheme could effectively ensure the capacitor voltage of each module in a small dynamic range, so that the STATCOM has a good effect of reactive power compensation of power grids. Finally, the MATLAB! Simulink simulation indicated the proposed schemes has a better effect on voltage balance.
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2017年第5期1685-1692,共8页
Journal of Guangxi University（Natural Science Edition）
基金
国家自然科学基金资助项目(61663021)
甘肃省科技支撑计划项目(1304GKCA023)
兰州市科技攻关计划项目(2013-4-18)
