船舶直流电网模块化电力变换器短路保护研究

Study on Short Circuit Protection of Modular Power Converters for Shipboard DC Power System

针对大功率电力变换器模块化设计带来的内部模块发生短路故障可能性增加的问题,提出模块短路时模块与整机之间的选择性保护方案。由于受限于采用固态断路器带来的尺寸和重量的显著增加,研究提出了利用模块化电力变换器与内部变换模块之间输入回路电流级差,在变换器以及内部模块输入回路串联不同限流熔断器的方案,仿真结果验证了该方案的可行性,并做了扩展讨论分析,结果表明该方案具有实现简单,可靠的特点,提高了船舶直流电网电力变换器的运行可靠性。

Aiming at the problem of increasing possibility of short circuit failure of internal module caused by modular design of high-power power converter the selective protection scheme between the module and the whole machine is proposed when the module is short circuit.Aiming at the heavy size and weight of solid state breakers and considering the current gradation difference of power converter and inside conversion modules,the solution of installing different hybrid current limiting fuses at the input loop of whole power converter and within conversion modules is proposed.The simulation results shows that the functions of selective protection can be achieved easily and reliability.The extended discussion and analysis of the scheme are made.The results show that the scheme has the characteristics of simple implementation and reliability,and the operation reliability of the power converter of the ship DC power grid is improved.