基于能量平衡的降低模块化多电平变换器子模块电容电压波动控制策略

发布时间：2018-08-19 18:13

【摘要】：电容器是模块化多电平变换器(MMC)子模块的关键部件,降低子模块电容电压波动是提高电容器可靠性和降低变换器成本的双重要求。首先分析不同环流对MMC电容电压波动的影响,指出注入典型2次环流是降低电容电压波动和减少器件损耗较好的折中方案。然后,在介绍已有基于工频周期的能量平衡控制策略基础上,提出基于控制周期的能量平衡控制策略,在达到注入典型2次环流降低MMC电容电压稳态波动的同时又能取得较好的暂态性能。所提出的基于能量平衡的控制策略,与常规PI控制器相比避免了繁琐的参数整定过程,并适应各种工况。最后,通过仿真和实验验证了所提控制策略的有效性。
[Abstract]:Capacitor is the key component of the modularized multilevel converter (MMC) submodule. Reducing the voltage fluctuation of the submodule capacitor is the dual requirement to improve the reliability of the capacitor and reduce the cost of the converter. Firstly, the influence of different circulation on the voltage fluctuation of MMC capacitor is analyzed, and it is pointed out that injecting typical second circulation is a good compromise scheme to reduce the voltage fluctuation of capacitance and reduce the device loss. Then, on the basis of introducing the existing energy balance control strategy based on the power frequency period, the energy balance control strategy based on the control period is proposed. At the same time the stable fluctuation of MMC capacitor voltage can be reduced by injecting typical second circulation at the same time better transient performance can be obtained. Compared with the conventional Pi controller, the proposed control strategy based on energy balance avoids the tedious parameter setting process and adapts to various working conditions. Finally, the effectiveness of the proposed control strategy is verified by simulation and experiments.
【作者单位】：清华大学电机系电力系统及发电设备安全控制和仿真国家重点实验室;昆明理工大学电力工程学院;
【基金】：国家自然科学基金重大项目资助(51490680,51490683)
【分类号】：TM46

【参考文献】