Ming as a station with spare change to meet the reliability requirements

Generally of a large electricity substation DC system power rectifier circuit breaker operating mechanism of energy storage power, disconnector operating power supply and cooling transformer OLTC power supply, communication power, lighting, power production, supply and maintenance life significant load power supply is required to have high reliability. 220 kV substation electricity systems are generally installed two electric meter stations, which are connected to the high pressure side should be on a different power supply, spare each other. 500 kV Substation, mostly installed three stations with variable and has a station connected to the external power supply, as the other two stand out with spare change to meet the reliability  power transformers . Substation transformer low voltage side of the main circuit breaker is typically configured undervoltage release, when the grid instantaneous fluctuations, flicker, regardless of station power low voltage bus will run in parallel or breakdown of the low voltage side of the transformer station to use the main circuit breaker tripped. Due to the low voltage circuit breaker undervoltage trip function generally do not have the automatic reclosing function, especially unmanned substation to substation stable operation of impact, therefore, some large substation transformer substation canceled the low pressure side of the main breaker undervoltage trip function.