US Patent 11833910 Dynamic isolation monitoring with low sensitivity to noise

A method of monitoring a battery system includes connecting a voltage divider circuit to a battery of the battery system; measuring a first battery voltage; sampling a first chassis voltage for less than a settling time of the first chassis voltage and estimating a settled value of the first chassis voltage using sampled values of the first chassis voltage; changing a configuration of the voltage divider circuit; measuring a second battery voltage; sampling a second chassis voltage for less than a settling time of the second chassis voltage and estimating a settled value of the second chassis voltage using sampled values of the second chassis voltage; and determining isolation impedance of the battery to a chassis using the first and second battery voltages and the estimated settled values of the first and second chassis voltages.