Practical Study Of Fault Disposal In Feeder Automation System

As the development of the economy, the consumers hope the quality and dependability higher and higher. The structure and automation level of distribution can not meet the demands, more and more power suppliers are reconstructing the structure of distribution and adopting thedistribution automation. So it is very necessary to develop a set of distribution automation, which is of high dependability and powerful function. Aiming to this, the thesis analyzed and studied on some important problems of distribution automation, including DLC (distribution line carrier), the dependability of FTU (Feeder Terminal Unit) and selecting the distribution of earth fault. After acquiring the data of the experiment on a real distribution system, the thesis built the model of attenuation and analyzed the attenuation of DLC in the normal and default case, which proved that DLC is feasible and dependable. In order to improve the dependability of FTU, this thesis designed the circuit of power, watching and controlling, it also took some valid measurements to improve the capability of anti-jamming after analyzing the source and mode of jam, which assured the FTU passed the test successfully. The thesis also studied the method of select the line of earth fault, which is combining the negative sequence vector and injecting the modulated signal, the analysis and simulation proved it is a valid method. The PWM amplifier for injecting signal and the circuit of receiving signal were also made and tested, the result is as prospective. Dong xiawei(electric power engineering) Directed by prof. Qin lijun...