DEVICE AND METHOD FOR MONITORING AN ELECTRICAL INSULATION IN A VEHICLE ELECTRICAL SYSTEM

摘要

A device for monitoring an electrical insulation in the case of a vehicle electrical system of a vehicle, includes: a voltage source for generating direct voltages having a first and a second voltage value; a voltage-measuring unit between a positive and a negative power supply line of the vehicle electrical system for measuring a voltage between the positive and the negative power supply line; a current path between a positive current connection of the voltage source and the positive power supply line; a current-measuring unit in the current path for measuring a current flowing through the current path; a determining unit designed to determine an insulation resistance between the vehicle electrical system and an electrical ground from voltage measurement values of the voltage-measuring unit, current measurement values of the current-measuring unit, and the first and the second voltage value.

主权项

1. A device for monitoring an electrical insulation in an on-board system, the device comprising:
a voltage source for generating a first DC voltage with a first voltage value and a second DC voltage with a second voltage value; a voltage-measuring unit between a positive power supply line of the on-board system and a negative power supply line of the on-board system for the measurement of a voltage between the positive and negative power supply line; a current path between a positive power connection of the voltage source and the positive or the negative power supply line; a current-measuring unit in the current path for the measurement of a current-flowing in the current path; and an evaluation unit electrically connected via a first signal input to a signal output from the voltage-measuring unit and via a second signal input to a signal output from the current-measuring unit, the evaluation unit designed to determine, from a first measured voltage value measured in response to the first DC voltage and from a second measured voltage value measured in response to the second DC voltage on the voltage-measuring unit from a first measured current value measured in response to the first DC voltage and a second measured current value measured in response to the second DC voltage on the current-measuring unit, and from the first voltage value and the second voltage value, an insulation resistance between the on-board system and electrical ground.