METHOD FOR THE SELF-DIAGNOSIS OF A CIRCUIT FOR MEASURING THE INSULATION RESISTANCE OF A HIGH-VOLTAGE SYSTEM

• Main Author: SCHUSTER, Franz-Josef
• Format: Patent
• Language: English; French; German
• Published: 05.06.2024
• Subjects: MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; TESTING

The invention relates to the self-diagnosis of a circuit for measuring the insulation resistance of a battery system, the circuit having a first switch, which connects the positive terminal of the battery system to earth via a series-connected first comparator resistor, and a second switch, which connects the negative terminal of the battery system to earth via a series-connected second comparator resistor. Current measurements are made via the closed first switch to obtain a measured first current flow and via the closed second switch to obtain a measured second current flow, wherein at any one time only one of the two switches closed, the theoretical current flow via the switches is calculated on the basis of the voltage of the battery system and the size of the comparator resistor, and the measured current flow, is compared with the associated theoretical current flow, wherein an error signal is output and/or an error action is carried out when the result of the comparison is above or below a predefined reference value range.