A primary and secondary equipment integrated intelligent distribution system breaker to better locate and isolate faults

Abstract

As electrification deepens and the society relies more and more on electricity, dependability and safety standard of the power distribution system becomes higher and higher. What’s more, to minimize carbon emission, high percentage of renewable energy resources penetration is becoming a reality, which further complicates the distribution system. Because of equipment failure, animal intrusion and other causes, power system faults are inevitable. Fault section identification, location and isolation is a critical mission in distribution system operation [1]. As the distribution system develops and evolves, two main ways to accomplish this goal were established in distribution system: a) Substation overcurrent relay detects the fault and the corresponding substation breaker isolates the fault Then trial-and-error method is used to identify and isolate the fault section; b) Distributed sensors are deployed in the distribution system. Distribution system automation software in the operation center then collects fault information sent from all the distributed sensors. Operation stuff make a judgement on the fault section and fault isolation is done on a remote control or manual operation fashion.These methods leave a lot of room for improvements, which will be elaborated in the paper. A primary and secondary equipment integrated intelligent distribution system breaker is proposed, depending on which the shortcomings of the aforementioned methods can be overcome. This integrated breaker acquires and analyzes traveling wave signals and fundamental frequency signals, and then locate and isolate faults based on fault analysis results under various scenarios, including renewable energy resources integration. With this breaker, fault location accuracy and fault isolation selectivity and speed can be improved, which helps with distribution system reliability, safety, and economic operation.