Research On Power Capacitor Over-voltage Cycle Test Technology And Equipment

Power capacitor over-voltage cycle test is one type test to verify that repeated over-voltage cycle on power capacitor does not result in over-voltage dielectric breakdown from the lowest temperature rated (-40°C) to room temperature. It is the indispensable link in identification of new products. Type test is based on product standard; China’s power capacitor over-voltage cycle test standard is GB/T 11024.2-2001.This paper was aimed to meet the the actual requirement that the power capacitor plant must use high-power capacitor and high voltage power capacitor equipment to have the type test. By reading a lot of literature, the paper studied the power capacitor over-voltage cycle test technology combined with previous research practice. The power capacitor capacitor over-voltage cycle test equipment was designed. The following work was carried out:First of all, some current methods of power capacitors over-voltage cycle test were summarized. The actual state of the power capacitor over-voltage test technology development was introduced. The current power capacitors over-voltage cycle test methods were deeply analyzed. A new method to control the power capacitor over-voltage waveform directly was put forward and Matlab / Simulink simulation analysis was carried out. The cascade resonant method and parallel resonant method of the power capacitor over-voltage cycle test were deeply comparative analyzed, at the same time the paper expounded the mechanism of the parallel resonance test method to reduce power supply capacity.Second, this paper designed the power capacitors over-voltage cycle test equipment with advanced technology including power electronic technology, single-chip technology, and high-voltage testing techniques etc. This equipment can meet the requirements of 340kVar/4.5kV power capacitor over-voltage cycle test.The function of the equipment include automatic voltage regulation of resonance, monitoring and display, over-current and over-voltage protection. This equipment is able to carry out test data storage and management of power capacitors to provide a basis for type test.Third, this paper designed small-scale model experiment based on power capacitor over-voltage cycle test principle.The test data was analyzed and compared. The experiment in this paper proved that the principle of the power capacitors over-voltage cycle test circuit is correct, easy to control.