Abstract: Systems and methods are provided for monitoring current in an electric motor. An electrical system includes a (DC) interface, an electric motor, an inverter module coupled between the DC interface and the electric motor, a first current sensor between a first phase leg of the inverter module and a first phase of the electric motor to measure a first current flowing through the first phase of the electric motor, a second current sensor between the first phase leg and the DC interface to measure a second current flowing through the first phase leg, and a control module coupled to the first current sensor and the second current sensor. The control module is configured to initiate remedial action based at least in part on a difference between the first current measured by the first current sensor and the second current measured by the second current sensor.

Abstract: Systems and methods are disclosed to improve torque linearity of an electric machine when operating in a field-weakening region. The systems and methods adjust the q-axis and the d-axis components of the stator current commands of the electric machine using a flux weakening control loop and a torque linearity control loop such that torque linearity is maintained when the machine operates in a field weakening region of operation.

Abstract: Systems and methods are disclosed for a dual voltage-source inverter system. The systems and methods selectively couple a first voltage source and a second voltage source to an inverter via a controllable switch.

Abstract: A system is provided for controlling two alternating current (AC) machines via a five-phase PWM inverter module. The system comprises a first control loop, a second control loop, and a current command adjustment module. The current command adjustment module operates in conjunction with the first control loop and the second control loop to continuously adjust current command signals that control the first AC machine and the second AC machine such that they share the input voltage available to them without compromising the target mechanical output power of either machine. This way, even when the phase voltage available to either one of the machines decreases, that machine outputs its target mechanical output power.

Abstract: A method for controlling a traction power inverter module (TPIM) in a vehicle includes determining a commanded output torque of the motor using a controller. The method further includes controlling the TPIM and motor using a discontinuous pulse width modulated (DPWM) signal when the commanded output torque is less than a calibrated torque threshold. A continuous pulse width modulated (CPWM) signal is used when the commanded output torque is greater than the threshold. The method may include determining a direction of a change in the commanded output torque, and controlling the TPIM, via the controller, using the DPWM signal only when the commanded output torque drops below a predetermined hysteresis level. A vehicle includes a traction motor producing a motor torque for propelling the vehicle, an ESS, a TPIM, and a controller configured as noted above.

Abstract: Methods and systems for controlling a power inverter in automobiles utilizing two-mode transmissions are provided. The various embodiments control the power inverter by, responsive to a commanded torque of the electric motor being below a first torque level, controlling the power inverter to set a switching frequency of the power inverter at a first set frequency; and, responsive to the commanded torque of the electric motor being between the first torque level and a second torque level, controlling the power inverter to determine the switching frequency of the power inverter as a function of the commanded torque of the electric motor while maintaining the switching frequency above a dynamic frequency limit. The method reduces switching frequencies in the inverter at high commanded torques, while maintaining the switching frequencies above dynamic frequency limit that provides effective control over the motor.

Abstract: Methods and systems are provided for assessing a vehicle transmission having a resolver. A memory is configured to store preliminary data pertaining to an error of the resolver. A processor is coupled to the memory, and is configured to determine a harmonic characteristic of the preliminary data, and to assess the vehicle transmission using the harmonic characteristic.

Abstract: A system is provided for controlling two AC machines. The system comprises a DC input voltage source that provides a DC input voltage, a voltage boost command control module (VBCCM), a five-phase PWM inverter module coupled to the two AC machines, and a boost converter coupled to the inverter module and the DC input voltage source. The boost converter is designed to supply a new DC input voltage to the inverter module having a value that is greater than or equal to a value of the DC input voltage. The VBCCM generates a boost command signal (BCS) based on modulation indexes from the two AC machines. The BCS controls the boost converter such that the boost converter generates the new DC input voltage in response to the BCS.

Abstract: Methods and systems for driving an automobile are provided. The system includes a prime mover power source and a two-mode, compound-split, electro-mechanical transmission, including first and second motors, coupled to the prime mover power source, a power inverter coupled to the first and second motors, and a processor coupled to the first and second motors and the power inverter. The processor is configured to modify a signal controlling the power inverter utilizing a first voltage distortion compensation method if a modulation index of the signal is less than a first modulation index value and modify the signal utilizing a second voltage distortion compensation method if the modulation index is at least equal to the first modulation index value.

Abstract: Methods and systems for operating an inverter coupled to an electric motor are provided. The inverter has a plurality of high switches and a plurality of low switches coupled to the electric motor. An event indicative of deceleration of the electric motor is detected. The inverter is alternated between a first mode of operation and a second mode of operation during the deceleration of the electric motor. In the first mode of operation, each of the plurality of high switches is activated and each of the plurality of low switches is deactivated. In the second mode of operation, each of the plurality of low switches is activated and each of the plurality of high switches is deactivated.

Abstract: Methods and systems for operating an inverter having a plurality of high switches and a plurality of low switches coupled to an electric motor are provided. An event indicative of deceleration of the electric motor is detected. The inverter is alternated between a first mode of operation and a second mode of operation during the deceleration of the electric motor. In the first mode of operation, each of the plurality of high switches is activated and each of the plurality of low switches is deactivated or each of the plurality of low switches is activated and each of the plurality of high switches is deactivated. In the second mode of operation, each of the plurality of high switches is deactivated and each of the plurality of low switches is deactivated.

Abstract: Methods and systems for operating an electric motor having a plurality of windings with an inverter having a plurality of switches coupled to a voltage source are provided. A first plurality of switching vectors is applied to the plurality of switches. The first plurality of switching vectors includes a first ratio of first magnitude switching vectors to second magnitude switching vectors. A direct current (DC) current associated with the voltage source is monitored during the applying of the first plurality of switching vectors to the plurality of switches. A second ratio of the first magnitude switching vectors to the second magnitude switching vectors is selected based on the monitoring of the DC current associated with the voltage source. A second plurality of switching vectors is applied to the plurality of switches. The second plurality of switching vectors includes the second ratio of the first magnitude switching vectors to the second magnitude switching vectors.

Abstract: A method for controlling an inverter coupled to an electric motor for a vehicle includes generating a discontinuous PWM signal for the inverter when a torque of the electric motor and a speed of the electric motor are substantially zero, and when at least one predetermined vehicle condition is met.

Abstract: Methods, system and apparatus are provided for overmodulation of a five-phase machine in a vector controlled motor drive system that includes a five-phase PWM controlled inverter module that drives the five-phase machine. Techniques for overmodulating a reference voltage vector are provided to optimize voltage command signals that control a five-phase inverter module to increase output voltages generated by the five-phase inverter module.

Abstract: Methods and systems are provided for controlling an electrical system of a vehicle. Sensors are used to obtain first data for a first path of calculations and second data for a second path of calculations. The first path comprises a first plurality of calculations of generating a value of a parameter pertaining to the electrical system, and the second path comprises a second plurality of calculations of monitoring the electrical system with respect to the first path. A processor is coupled to the plurality of sensors, and is configured to determine whether a data frozen flag is active, perform the first plurality of calculations of the first path using the first data if the first data flag is inactive, and perform the second plurality of calculations of the second path if the first data flag is active.

Abstract: Methods and systems are provided for monitoring an electrical system of a vehicle. Data pertaining to the electrical system is obtained. Calculation modules are performed using the data to generate intermediate determinations. An aggregate calculation module is performed using each of the intermediate determinations to generate an aggregate determination pertaining to the electrical system. Redundant intermediate calculations are performed using the data to generate redundant intermediate determinations. Each of the redundant intermediate determinations is used for comparison with a respective intermediate determination.

Abstract: A method of detecting a phase winding fault in a multi-phase electric machine is executable via a motor controller, and includes measuring feedback signals of the machine, including each phase current, and generating reference phase voltages for each phase. The method includes calculating a predetermined voltage value using the feedback signals and reference phase voltages, and comparing the voltage value to a corresponding threshold to determine the fault. A control action is executed when the voltage value exceeds the corresponding threshold. The voltage value is one or more of: a ratio of a normalized negative sequence voltage to a modulation index, an RMS voltage for each phase, and total harmonic distortion of each phase current. An apparatus detects the fault, and includes a motor controller and an algorithm as set forth above. The apparatus may include a voltage inverter for generating a multi-phase alternating current output for powering the machine.

Abstract: Systems and apparatus are provided for an inverter system for use in a vehicle. The inverter system comprises a six-phase motor having a first set of three-phase windings and a second set of three-phase windings and a three-phase motor having a third set of three-phase windings, wherein the third set of three-phase windings is coupled to the first set of three-phase windings and the second set of three-phase windings. The system further comprises a first energy source coupled to a first inverter adapted to drive the six-phase motor and the three-phase motor, wherein the first set of three-phase windings is coupled to the first inverter, and a second energy source coupled to a second inverter adapted to drive the six-phase motor and the three-phase motor, wherein the second set of three-phase windings is coupled to the second inverter. A controller is coupled to the first inverter and the second inverter.

Abstract: Methods and systems for controlling an electric motor are provided. The electric motor includes at least one winding. A winding current flowing through the at least one winding is monitored. The winding current has an oscillating component and an offset component. The offset component of the winding current is isolated from the oscillating component of the winding current. The electric motor is controlled based on the offset component of the winding current.

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.