Abstract: Methods and systems for controlling motor torque in a hybrid vehicle are provided. A current sensor provides a feedback current when the sensor is operating properly. A processor controls the motor torque using the feedback current if the current sensor is operating properly. The processor controls the motor torque using a slip value for the hybrid vehicle if the current sensor is not operating properly.

Abstract: Methods and systems are provided for motor torque control for hybrid vehicles having a motor and a communications bus. The motor torque is controlled using a first motor torque capacity if the communications bus is healthy. The motor torque is controlled using a second motor torque capacity if the communications bus is unhealthy. The first motor torque capacity has a first absolute value. The second motor torque capacity has a second absolute value that is less than the first absolute value.

Abstract: A method is provided for controlling an induction motor having a rotor. The method includes receiving a torque command; comparing the torque command to a threshold torque value; generating, with a first estimation module, a first estimated rotor resistance when the torque command is less than or equal to the threshold torque value; generating, with a second estimation module, a second estimated rotor resistance when the torque command is greater than the threshold torque value; and generating control signals for the induction motor based on the first estimated rotor resistance or the second estimated rotor resistance.

Abstract: A hybrid electric vehicle (HEV) has an algorithm for executing a method for diagnosing a high-voltage (HV) fault condition aboard the HEV. The HEV includes a high-voltage (HV) battery, an auxiliary power module (APM), a power inverter module (PIM), and a three-phase motor/generator unit (MGU). A controller executes the method to thereby measure a DC output current from the HV battery, a DC inlet current into the APM, and a pair of AC phase currents in the MGU. The method further includes calculating a DC inlet current into the PIM using the AC phase currents, diagnosing the HV fault condition using the DC output currents and the DC inlet currents, and executing a control action in response to the diagnosed condition. The method can include shutting off the APM to determine whether the APM is the root cause of the HV fault condition.

Abstract: Methods and apparatus are provided for determining whether one or more inverter sub-modules of an inverter module is operating properly. Amplitude of each stator current signal is regularly measured. For each current signal, a positive counter counts a number of consecutive times the amplitude of that current signal is less than a positive current threshold, while a negative counter counts a number of consecutive times the amplitude of that current signal is greater than a negative current threshold. If the positive counter or the negative counter exceeds a maximum count, it is determined that an inverter sub-module is operating abnormally.

Abstract: A control system is provided for an inverter assembly associated with an induction motor. The system includes a current determination module configured to generate q- and d-axis current commands based on a torque command. The current determination module is further configured to generate the q-axis current command based on an observed flux linkage and a flux linkage command. The system further includes a motor current control module coupled to the current determination module and configured to generate q- and d-axis voltage commands based on the q- and d-axis current commands generated by the current determination module and a PWM modulator coupled to the motor current control module configured to generate duty cycle signals for operating the inverter assembly based on the q- and d-axis voltage commands generated by the motor current control module.

Abstract: A method for controlling an induction machine having a rotor includes the steps of obtaining a torque command, calculating an estimated squared value of resistance of the rotor using the torque command, determining an offset for the resistance of the rotor, and generating an updated measure of rotor resistance using the estimated squared value and the offset.

Abstract: Methods and apparatus are provided for startup of a permanent magnet alternating current (AC) motor. The method comprises the steps of detecting startup of the permanent magnet AC motor; detecting a mechanical oscillation of the permanent magnet AC motor when startup of the permanent magnet AC motor is detected; and, in response to detection of the mechanical oscillation of the permanent magnet AC motor when startup is detected, suppressing the mechanical oscillation of the permanent magnet AC motor.

Abstract: A method of processing a resolver fault in a motor generator unit (MGU) includes receiving a position signal from a resolver describing a measured angular position of a rotor of the MGU, determining the presence of the resolver fault using the position signal, and calculating or extrapolating an estimated rotor position when the resolver fault is determined. A predetermined resolver fault state may be determined using a measured duration of the resolver fault, and the MGU may be controlled using the estimated rotor position for at least a portion of the duration of the resolver fault. A motor control circuit is operable for processing the resolver fault using the above method, and may automatically vary a torque output or a pulse-width modulation (PWM) of the MGU depending on the duration of the resolver fault.

Abstract: Methods and apparatus are provided for determining whether one or more inverter sub-modules of an inverter module is operating properly. Amplitude of each stator current signal is regularly measured. For each current signal, a positive counter counts a number of consecutive times the amplitude of that current signal is less than a positive current threshold, while a negative counter counts a number of consecutive times the amplitude of that current signal is greater than a negative current threshold. If the positive counter or the negative counter exceeds a maximum count, it is determined that an inverter sub-module is operating abnormally.

Abstract: In a motor controller, a modified interpolation technique uses an extrapolated torque command for the upper table to improve torque linearity under certain conditions. When the torque command input is greater than the max torque limit of a first look-up table, but less than the maximum torque limit of a second, adjacent look-up table, the desired current command is computed by interpolating between the maximum torque limit of the first table and a revised torque value for the second look-up table, wherein the revised torque value is determined by extrapolating from the maximum torque limit of the first look-up table through a torque value based on the torque command input.

Abstract: Methods and systems are provided for detecting loss of isolation of a motor, connections, or phase cables while an AC motor is operating. The system includes a power supply that is substantially isolated from the ground or chassis having a power supply voltage, and a power inverter electrically coupled to the power supply. The power inverter is configured to provide AC current from the power supply in an AC phase at an AC terminal, with the phase having current at a fundamental frequency that controls the motor speed. An electric motor is electrically coupled to the AC terminal of the power inverter and has a chassis that is substantially electrically isolated from the AC terminal of the power inverter under normal operating conditions. A processor is configured to control the AC current provided by the power inverter. The processor is configured to receive a first voltage signal related to current flowing through a motor chassis.

Abstract: A hybrid electric vehicle (HEV) has an algorithm for executing a method for diagnosing a high-voltage (HV) fault condition aboard the HEV. The HEV includes a high-voltage (HV) battery, an auxiliary power module (APM), a power inverter module (PIM), and a three-phase motor/generator unit (MGU). A controller executes the method to thereby measure a DC output current from the HV battery, a DC inlet current into the APM, and a pair of AC phase currents in the MGU. The method further includes calculating a DC inlet current into the PIM using the AC phase currents, diagnosing the HV fault condition using the DC output currents and the DC inlet currents, and executing a control action in response to the diagnosed condition. The method can include shutting off the APM to determine whether the APM is the root cause of the HV fault condition.

Abstract: A system and method for controlling an IPM synchronous machine in a vehicle that calculates an operating trajectory of the machine on-line. The system defines three operating ranges of the machine based on voltage magnitude, where a first operating range is controlled by a current limit of the machine and second and third operating regions are controlled by a voltage limit of the machine. The system calculates d- and q-axis current reference signals in the reference rotor frame for each of the three regions. The system determines which set of current reference signals will be used to control the machine based on the operating region. The third operating region is used during over-modulation of the machine.

Abstract: A control system for a hybrid powertrain includes an engine start detector that detects when an engine of the hybrid powertrain is activated via an electric motor during an auto start. An electric motor speed monitor determines a first speed of the electric motor for a first time and a second speed of the electric motor for a second time after detection of the engine in an active state. A control module determines a rate of change in speed of the electric motor based on the first speed and the second speed. The control module adjusts torque output of the electric motor during startup of the engine and based on the rate of change in speed.

Abstract: Methods and apparatus are provided for startup of a permanent magnet alternating current (AC) motor. The method comprises the steps of detecting startup of the permanent magnet AC motor; detecting a mechanical oscillation of the permanent magnet AC motor when startup of the permanent magnet AC motor is detected; and, in response to detection of the mechanical oscillation of the permanent magnet AC motor when startup is detected, suppressing the mechanical oscillation of the permanent magnet AC motor.

Abstract: Methods and apparatus are provided for generating zero-sequence voltages based on voltage commands and a motor output signal. At least one of the methods includes, but is not limited to, receiving a torque command and generating three-phase voltage commands based on the torque command. The method also includes, but is not limited to, generating a motor output responsive to the three-phase voltage commands and generating three-phase zero-sequence voltage samples based on the three-phase voltage commands and the motor output.

Abstract: Methods, apparatus, and systems are provided for regulating the operation of a drive system within a battery voltage and power range. The apparatus includes a PI regulator producing a signal for regulating a torque output of the drive system based on a DC voltage source limit and/or power limit, a converter normalizing the signal from the PI regulator to produce a new torque limit, and a switch selecting either the new torque limit or an available torque limit of the drive system. The PI regulator includes an integrator having an initial value based on the torque output of the drive system and a copper loss term.

Abstract: Methods, apparatus, and systems are provided for regulating the operation of a drive system within a battery voltage and power range. The apparatus includes a PI regulator producing a signal for regulating a torque output of the drive system based on a DC voltage source limit and/or power limit, a converter normalizing the signal from the PI regulator to produce a new torque limit, and a switch selecting either the new torque limit or an available torque limit of the drive system. The PI regulator includes an integrator having an initial value based on the torque output of the drive system and a copper loss term.

Abstract: Methods and system are provided for controlling permanent magnet motor drive systems. The method comprises the steps of adjusting a first current command in response to a first voltage error to produce a first adjusted current, adjusting a second current command in response to a second voltage error to produce a second adjusted current, limiting each of the first and second adjusted current below a maximum current, converting the first adjusted current to a first potential, converting the second current command to a second potential, and supplying the first and second potentials to the permanent magnet motor. The first voltage error is derived from the second current command, and the second voltage error is derived from the first current command.