Patent ID: 8005632

Claim:
Method for monitoring a current sensing system operative to monitor electrical current in a transmission line between an electrical storage device and an electrical machine comprising: providing a current sensing system comprising a first current sensor located between an electrical storage device and an electrical machine and linearly operative over a first range of electrical current to monitor a transmission line electrical current comprising an electrical current flowing between the electrical storage device and the electrical machine and to provide a first output of magnitude of the transmission line electrical current, and a second current sensor located between the electrical storage device and the electrical machine and linearly operative over a second range of electrical current that includes said first range of electrical current to monitor the transmission line electrical current and to provide a second output of magnitude of the transmission line electrical current; and receiving the first and second outputs at a control module, the control module being programmed to compare the first and second outputs of the magnitudes of the transmission line electrical current when the first and second outputs of the magnitudes of the transmission line electrical current are within said first range of electrical current and to output an indication of a first fault in the current sensing system when a difference between the first and second outputs of the magnitudes of the transmission line electrical current exceeds a summation of a first measurement accuracy of the first current sensor and a second measurement accuracy of the second current sensor.