Method and device for measuring insulation resistance of metalized film capacitor under high field strength

Abstract

The invention discloses a method and a device for measuring insulation resistance of a metalized film capacitor. The method comprises the following steps: placing the capacitor in an environment with constant temperature and humidity; serially connecting a mega-ohm level sampling resistor RS with the capacitor; applying direct-current high voltage to the capacitor and the sampling resistor; and calculating the insulation resistance of the metalized film capacitor under high field strength according to an intrinsic standoff ratio of the sampling resistor and the capacitor under the direct-current high voltage. The invention also provides the device for realizing the method, which mainly comprises a constant temperature humidity chamber, a capacitance measuring meter, a direct current high voltage resistance meter, a mega-ohm level sampling resistor, a direct current high voltage bleeder and a high voltage probe. The device can be used for accurately measuring the insulation resistance of the metalized film capacitor under the high field strength. The defects of a conventional insulation resistance measuring meter that the size of output voltage is limited, a voltage-resistance time is insufficient, the measurement of the insulation resistance is unstable, and the like, are overcome.

Description

technical field [0001] The invention belongs to the field of resistance measurement, in particular to a method and device for measuring the insulation resistance of metallized film capacitors, which are suitable for measuring the insulation resistance of large-capacity capacitors under constant temperature, constant humidity and high electric field strength. Background technique [0002] The existence of leakage current of metallized film capacitors under high field strength is an important factor affecting the performance of energy storage capacitors in pulse power supply systems, and insulation resistance is a basic electrical parameter reflecting leakage. [0003] Insulation resistance is the ratio of the DC voltage applied between two conductors on an insulator to the leakage current flowing through the insulator. Under a certain humidity condition, when a DC voltage is applied to the insulating material, the following currents will be generated inside and on the surface...

AI Technical Summary

Problems solved by technology

At present, conventional insulation resistance measuring instruments have problems such as limited measurement voltage, insufficient withstand voltage time and unstable insulation resistance measurement in measuring the insulation resistance of metallized film capacitors, and cannot accurately measure the insulation resistance of capacitors.

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