为了更加高效和快速替换模块化多电平换流器的故障子模块,提出一种基于动态调节的冗余子模块投入策略.利用冗余子模块进行了电压补偿,同时在每个控制周期内对替换子模块的导通时间进行了限幅控制,有效地避免了替换子模块投入充电过程中系统直流侧电压偏离正常值问题和直流侧由于替换子模块投入产生的较大有功电流冲击问题.仿真表明,该策略能极大地抑制冗余模块投入带来的交流输出侧电压波动,并有效抑制直流侧有功电流的冲击.%To replace the fault sub-module in an modular multilevel converter more efficiently and faster,a redundant sub-module replacement strategy based on dynamic regulation is proposed,which utilizes the redundant sub-module to compensate the voltage shortage and performs pulse width modulation to control the turning-on time of the substitution sub-module in each control cycle. In this way,the problems that arise during the charging process of the substitution sub-module,such as deviation of voltage from its normal value on DC-side and bigger active power current shock on DC-side due to the substitution module,are avoided effectively. Simulation results show that the proposed strategy can re-strain the fluctuations of AC output voltage caused by the substitution module to a great extent,and restrain the active power current shock on DC-side effectively.
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