Arc Voltage Measurement System And The Research On Electrical Endurance Of Contact

High voltage circuit breaker is an important equipment in power system, which plays protection and control function. High voltage circuit breakers can produce arc in the making and breaking process. Arc voltage is an important parameters of reflecting the breaker arcing chamber performance. It can be observed the position of arcing point and quenching moment with measuring high voltage circuit breaker arc voltage waveform, thus accurately calculate burning arc time. Contactor electricity abrasion mainly depends on the burning arc time and opening circuit current. Electrical endurance is the most instable factor among those factors that affects circuit breaker in using life. Develop a set of arc voltage test system, and make the research based on the test data of contactor electrical endurance. It is conducive to understand conditions of the breaker contactor electricity abrasion and make a evaluation for circuit breaker product electrical endurance capability.The hardware composition and software design of arc voltage measurement system were described in detail. Firstly, by analyzing and calculating, the type and main parameters of signal extraction device were determined. A signal measurement device that can measure the opening current and arc voltage in real time was designed. To restrain the effect of strong electromagnetic field effectively on the transmission of data, the transmission system of data that used fiber as transmission medium for the reliability of data transmission. The setting of communication protocol further ensure reliability of data transmission. Multi-machine communication provides technical reserves for the reform of the test system and online monitoring equipments. The arc voltage software can achieve drawing graphics, serial communication settings and saving history. The effect of the conducting loop's voltage drop was eliminated, using the software compensation method. Ratio coefficient of the nonlinear region of voltage divider was adjusted using Lagrange interpolation to ensure the accuracy of test data. The reliability and accuracy of this test system to arc voltage were verified by experiment. This paper analyzed the factors influencing the electrical endurance of contact. Based on the actual test data from the system of arc voltage, select the arcing time of the first and the last opening phases, the breaking currents, the breaking time and the distribution of the first opening phase as the main factors influencing electrical endurance of contact. By using the fuzzy theory, set up a set of methods for evaluating the electrical endurance of circuit breaker.