US Patent 9601003 Sensor and control systems for electrical machines

A system for detecting sensor failure and/or operating with a failed sensor in an electrical machine includes an electrical machine, three or more sensors configured to connect to the electrical machine, and a sensor module operatively connected to each sensor to receive sensor signals from the sensors. The sensor module includes a failure detection module operatively connected to each sensor and configured to determine if each sensor is a failed sensor or a functioning sensor. The sensor module also includes a virtual sensor module operatively connected to the failure detection module and configured to output simulated sensor signals for the failed sensor, wherein the sensor module is configured to output the sensor signals for each functioning sensor. The system includes a control module operatively connected to the sensor module and the electrical machine to receive sensor signals and simulated sensor signals to control operation of the electrical machine.