Ground capacitance measuring apparatus and ground capacitance measuring method

摘要

An object of the present invention is to provide a ground capacitance measuring apparatus and a ground capacitance measuring method capable of accurately calculating a capacitance without accurately measuring an actual impedance of a facility. The ground capacitance measuring device always connects a limiting resistor to a tertiary side of a grounded transformer GPT connected to an ungrounded power system, and connects to a tertiary side of the grounded transformer GPT via a cable. Is a ground capacitance measuring device comprising a switch and a measurement resistor for measuring the ground capacitance of the three-phase batch of the power system, the resistance value between the limiting resistance to the measurement resistance as a variable, The ground capacitance is calculated using the maximum value of an arithmetic expression relating to the product of the ground capacitance and the angular frequency based on the circuit constant of the tertiary circuit of the power system and the ground transformer GPT. [Selection diagram] Fig. 1