BUSBAR INSULATION RESISTANCE RESULTS FOR ELECTRICAL INSULATION TESTING AND DIAGNOSTICS

摘要

The electrical busbar insulation for an electrified vehicle is detected in which a DC power source is connected to a plus and a minus busbar. The plus busbar is connected to ground and a resulting first current is detected that flows through a minus busbar isolation resistor and a balanced isolation resistor. The negative bus bar is connected to ground and a resulting second current is detected which flows through a minus busbar isolation resistor and a balanced isolation resistor. The plus and minus busbar insulation resistance is estimated in response to respective ratios of the first and second currents. An isolation value is compared to a threshold, wherein the isolation value is obtained from a voltage of the DC power source and a smaller one of the positive and negative bus bar insulation resistance. An untypical isolation is signaled when the isolation value is less than the threshold.