Patent ID: 9423446
Filing Date: 2016-08-23
CPC Classification: B60L,G01R

Claim Text:
1. An insulation state detecting device comprising: a positive side input terminal connected to a positive side power line of a high voltage DC power supply; a negative side input terminal connected to a negative side power line of the high voltage DC power supply; a ground electrode; a controller that detects insulation states between the positive side power line and the negative side power line and the ground electrode based on a charge voltage of a flying capacitor; and an equilibrium state forming circuit that promotes an operation of transiting a charge state of an electrostatic capacitance of a positive side capacitor between the positive side power line and the ground electrode and a charge state of an electrostatic capacitance of a negative side capacitor between the negative side power line and the ground electrode from non-equilibrium states to equilibrium states, wherein in the non-equilibrium states, amounts of electricity charges on the positive side capacitor and the negative side capacitor fluctuate; and wherein in the equilibrium states, the amounts of electricity charges on the positive side capacitor and the negative side capacitor are not changed.