Arc Light Protection System Of Marine Medium Voltage Switchgear

With the development of the marine industry,the capacity of ship power system keeps growing,and it has a tendency to grow in medium voltage.Medium voltage equipments may cause arc short circuit fault due to their own shortcomings,unusual working conditions,resonant overvoltage,insulation problems,poor current carrying loop,entry of external objects and personnel mishandlings,causing gas breakdown and igniting the arc.Because of limited space and more equipments in ship power system,the probability of causing problems has greatly increased.Based on the above reasons,it is necessary to install bus protections,that is,an arc protection of marine medium voltage switchgear.Firstly,this paper introduces the development of arc light protection system at home and abroad,and describes the differences of ship power system and land power system.This paper expounds the neutral grounding methods and arc grounding research of the present ship power system.Based on pscad software,models of single-phase metal grounding faults and single-phase arc light grounding faults are completed,and simulations are carried out according to the different grounding methods.Through Matlab software,the waveforms of different working conditions are obtained and analyzed.The Fourier transform and the wavelet transform are used to extract the characteristics of steady state and transient from the zero sequence current respectively,and getting the basis for judging the fault.This paper presents an device of arc light protection which is suitable for marine medium voltage switchgear and introduces its configuration strategy.