Patent ID: 7639021
Filing Date: 2009-12-29
Classification: B60L,B60W,G01R

Abstract:
1. A detection circuit for detecting a dielectric breakdown fault in an electric circuit having a high voltage battery, the circuit comprising: means for continuously monitoring the voltage of the high voltage battery; means for taking a first voltage reading of the high voltage battery at a first fixed time interval; means for taking a second voltage reading of the high voltage battery at a second fixed time interval; means for calculating the change between the first and second voltage readings over a change in time; means for comparing the first and second voltage readings to the voltage of the high voltage battery and generating a first output signal; means for storing the first output signal; means for taking a third voltage reading of the high voltage battery at a third fixed time interval; means for calculating the change between the second and third voltage readings over the change in time; means for comparing the change between the second and third voltage readings to the voltage of the high voltage battery and generating a second output signal; means for storing the second output signal; and means for adjusting at least one of the first, second or third time interval to estimate the steady state voltage wherein said output signals are used to determine the resistance of the dielectric breakdown fault.