Online partial discharge measuring device and coupling capacitor used for it

摘要

PROBLEM TO BE SOLVED: To separate a voltage waveform of a low frequency component and a partial discharge waveform of a high frequency component without using a voltage sensor (high voltage probe or the like), reduce the number of parts, and make an online portion having a simple configuration. A discharge measuring device and a coupling capacitor used for the discharge measuring device are provided. SOLUTION: A coupling capacitor C and a detection impedance Z are connected in order to a feeding line 31, 32, 33 connecting a power supply 10 and a measurement target 20, and grounded, and a signal detected by the detection impedance Z is measured. In an online partial discharge measuring device that separates a voltage waveform of a low frequency component and a partial discharge waveform of a high frequency component at 50, the coupling capacitor C is composed of a parallel circuit of a capacitor (capacitance) and a resistor (resistance component). , An alternating current of about commercial frequency is passed by a resistor (resistance component), and the voltage waveform of the low frequency component is detected. [Selection diagram] Fig. 5