Abstract: During a transient operating condition in an electric machine, a diagnostic routine associated with the electric machine may erroneously indicate a fault. According to the disclosure, a flag is set when a transient condition is detected. The flag is communicated to the diagnostic routine. The output of the diagnostic routine may be altered when the flag is set, i.e., when a transient is detected.

Abstract: A High Voltage Interlock Strategy (HVIS) uses feedback current to detect cable connectivity status for a high-voltage cable configured to connect a power conversion circuit with a remote permanent magnet synchronous machine (PMSM). One or more feedback factors are calculated based on detected feedback current. Various algorithms for calculating a feedback factor, and for determining connectivity status based on calculated feedback factors, can be practiced, according to the PMSM operational mode. Fault detection action can be performed in response to detecting a cable disconnect. The HVIS can be implemented by software, making it a safe, economical solution for cable connectivity detection.

Abstract: During a transient operating condition in an electric machine, a diagnostic routine associated with the electric machine may erroneously indicate a fault. According to the disclosure, a flag is set when a transient condition is detected. The flag is communicated to the diagnostic routine. The output of the diagnostic routine may be altered when the flag is set, i.e., when a transient is detected.

Abstract: A pulse width modulation (PWM) Frequency Adaptation Mechanism (PFAM) is configured to receive vehicle state input, and in response to the vehicle state input, provide a PWM parameter for PWM switching of electronics in a power conversion circuit of an electric drive system (EDS) for a hybrid electric vehicle. In one example, a PWM parameter that reduces the audible noise generated by PWM switching can be designated by the PFAM. A PFAM can be configured to receive user input regarding user preference for a default mode or a noise reduction mode. Vehicle state input can include input related to vehicle motion, climate control system state, engine state, EDS state, vehicle body state and audio system state. By way of example, a PWM noise reduction parameter can comprise a high PWM switching frequency, or a random frequency hopping about a low PWM switching frequency.

Abstract: A High Voltage Interlock Strategy (HVIS) uses feedback current to detect cable connectivity status for a high-voltage cable configured to connect a power conversion circuit with a remote permanent magnet synchronous machine (PMSM). One or more feedback factors are calculated based on detected feedback current. Various algorithms for calculating a feedback factor, and for determining connectivity status based on calculated feedback factors, can be practiced, according to the PMSM operational mode. Fault detection action can be performed in response to detecting a cable disconnect. The HVIS can be implemented by software, making it a safe, economical solution for cable connectivity detection.