New 132kV and 22kV GIS / Insulated busbar configurations will be adopted for HK
Electric’s MRS Substation. Unit busbar protection is used to ensure prompt and discriminative
isolation of the faulty busbar and to minimize the supply interruption to customers. Traditional
high impedance differential protection is applied as main protection for the busbars of the new
132kV and 22kV busbar configurations because it is simple, reliable and well-proven in HK
Electric
This paper