The Topology Design And Protection Research Of Space Power Station Power Transmission System

The space power station(SPS)is not affected by atmospheric,seasonal and diurnal variations,and it can receive the stable solar radiation for 99%time of a year.Thus the SPS is suitable for the large-scale exploitation and utilization of solar energy.The power transmission system(PTS)is an indispensable part of SPS.The topology design and protection of PTS is an important part of SPS research.This paper focuses on MW-level non spotlight multi-rotary joints SPS,and the topology of the PTS is designed.The hybrid high voltage DC circuit breaker,which is necessary for detection of PTS,is studied,and the protection configuration scheme of the PTS is designed in this paper.This paper introduces briefly the scheme of the MW-level non spotlight multi-rotary joints SPS system,and designs a topology scheme of high-and low-voltage hybrid PTS.The designed scheme can improve the efficiency of PTS,reduce the volume and weight of PTS,and improve the reliability of the power supply to the service system equipment.The overall topology is narrated.Compared with two existing topology schemes,advantages of the proposed scheme are illustrated.The topology of high-voltage power transmission system(HVPTS)is designed.Combined with characteristics of space environment and microwave source,the control strategy of HVPTS is designed.The simulation model of HVPTS is built in PSCAD/EMTDC,and the stable operation state of HVPTS is simulated.Simulation results verify the feasibility of the designed topology and the effectiveness of the control strategy,which lays a foundation for studying fault characteristics and protection configuration scheme of HVPTS at the same time.Combined with requirements of SPS and particularity of space environment,this paper analyses the reason for using the forced-commutate hybrid high voltage DC circuit breaker(FC-HHVDCCB)in SPS.In view of the shortcoming of existing schemes,this paper propose a new scheme of FC-HHVDCCB.The proposed scheme can shorten the total time of fault current cut-off,accelerate the speed of short circuit fault removal,reduce the pressure on the arrester,prolong the useful life of the arrester,and reduce the difficulty of engineering technology.In addition,the cost of the scheme is low,and the volume of the scheme is small.Meanwhile,the proposed scheme can also solve the coordination problem of the circuit breaker with disconnecting switch in closing opration.In this paper,the topology and working principle are firstly narrated,and the working principle include the process of short circuit fault removal,the closing process,and the opening process.Next,the simulation verify feasibility and effectiveness of the proposed FC-HHVDCCB scheme.Finally,the features of the proposed scheme are further illustrated by comparing with the three existing schemes.In this paper,the fault characteristics of HVPTS is analyzed,and two kinds of fault cases are analyzed:the fault of the main bus and the fault of the sub bus.The requirements of the system protection are given,and the simulation analysis is carried out.Simulation results verify the correctness of the fault characteristics analysis.In view of the shortcomings of traditional protection configuration schemes of HVPTS,a new protection configuration scheme is designed by using the scheme of FC-HHVDCCB proposed in this paper.The designed protection configuration scheme has better protection selectivity,and the number of DC circuit breaker needed is less.The volume of the system is small,and the cost is low.In addition,the selection method of the current limiting inductance is given.Simulation results verify that the designed protection configuration scheme can meet the requirements of system protection,and has feasibility and better protection selectivity.In the end,considering the characteristics of service system facilities,the topology and control strategy of low-voltage STS is designed.The control strategy include the light period and the shadow period.The simulation model is built in PSCAD/EMTDC.Simulation results verify the feasibility of the designed topology and the effectiveness of the designed control strategy.