A ground fault detection apparatus connected to an ungrounded battery supplying power via a step-up circuit to a load and calculating insulation resistance of a system provided with the battery to detect a ground fault includes a capacitor, a set of switches switching among a V0 measurement path, a Vcn measurement path, and a Vcp measurement path, a bypass resistor connected in parallel with the negative-electrode-side insulation resistance via a normally open switch, and a control unit configured to, when the insulation resistance is to be calculated based on a charge voltage measurement value of the capacitor in each of the measurement paths, in a case in which the charge voltage measurement value of the capacitor in the Vcn measurement path is regarded as 0, switch the normally open switch to a closed state and measure the charge voltage of the capacitor in the Vcn measurement path.
Ground fault detection apparatus
2020-04-07
Patent
Electronic Resource
English