Research on the Architecture of Highly Reliable Self-powered System for Modular Multilevel Medium Voltage DC Converters
Modular multi-level DC converters have received extensive attention from industry and academia with the rapid development of large-capacity medium-voltage DC power distribution technology.However,achieving highly reliable auxiliary power supply is one of the key technical bottlenecks to realize the application of DC converters in medium-voltage DC power distribution scenarios.To this end,this paper proposes a highly reliable self-powered system architecture for modular multi-level medium-voltage DC converters.The architecture realizes the medium-voltage direct power supply of the central controller and sub-modules,so that no additional low-voltage DC power supply is required,and the system startup speed is greatly improved.Based on this architecture design,the auxiliary power supply of the sub-module controller and the bypass switch for modular multi-level medium-voltage DC converters have achieved three times redundancy,which improves the fault-tolerant operation capability of the system.A voltage balancing method of sub-module capacitors based on the autonomous control of auxiliary power supply in the pre-charging stage is proposed,which ensures the reliable pre-charging of the modular multi-level DC converter.Finally,the feasibility of the proposed auxiliary power supply system architecture is verified by experiments.
modular multi-level DC converterself-poweredmedium-voltage direct power supplysub-module capacitor voltage balancing
国家科技期刊平台
NSTL
万方数据
维普
