Abstract: Systems and methods are provided for diagnosing stator windings in an electric motor. An exemplary method for diagnosing stator windings in an electric motor involves determining an input energy imbalance across phases of the stator windings for an electrical period of the electric motor and identifying a fault condition when the input energy imbalance is greater than a first threshold value. In some embodiments, an input energy ratio across phases of the stator windings is also determined for the electrical period, wherein the fault condition is identified as a phase-to-phase short circuit fault condition when the input energy ratio is greater than a second threshold value and the input energy imbalance is greater than the first threshold value, or alternatively, as an in-phase short circuit fault condition when the input energy ratio is less than the second threshold value.

Abstract: A system for and method of reducing the effects of preheat period variation in shape memory alloy actuation, include sensing the removal of motion delay due to slack, backlash, and/or compliance in the actuator and drive-train of the system, and determining actuator activation, as a result thereof.

Abstract: An electric machine includes a stator core defining a number of stator slots (Z). A rotor assembly is positioned at least partially within the stator core. The rotor assembly includes at least one permanent magnet and defines a number of poles (M). A plurality of stator windings are positioned in the number of stator slots and define a number of phases (M). The machine defines a non-integer slots per pole per phase value (X), which is expressed as a mixed fraction in the form of A.(B/C), where A, B and C are integers. Optimal configurations for the electric machine are specified that maximize torque while minimizing torque ripple, noise and manufacturing complexity. In one embodiment, the slots per pole per phase value (X) is 2½. In another embodiment, the slots per pole per phase value (X) is 3½.

Abstract: An on-vehicle DC/DC converter transforms high-voltage electric power originating from an on-vehicle high-voltage source to low-voltage electric power at a regulated voltage level. The low-voltage electric power is distributed by a low-voltage bus. A method for operating the DC/DC converter includes monitoring a state of charge and a temperature of a low-voltage battery connected to the low-voltage bus, setting a DC/DC converter command to a nominal voltage level as a function of the state of charge and temperature of the low-voltage battery, monitoring a total low-voltage electric load, and adjusting the DC/DC converter command to a minimum low-voltage reference voltage when the vehicle is operating below a predetermined speed and the total low-voltage electric load is greater than a predetermined load.

Abstract: A method for executing mechanical overload protection to prevent commanding a control signal to a linear actuator that may mechanically overload the linear actuator when an overload condition of the linear actuator is detected, the linear actuator utilized for controlling a movable element associated with the linear actuator responsive to the control signal, includes monitoring an overload condition based on position change of the movable element associated with the linear actuator during an integration period and excess energy during the integration period, de-energizing the linear actuator when an overload condition has been detected, monitoring an overload retry counter based on the number of cycles the overload condition is detected, comparing the overload retry counter to an overload retry threshold, an reenergizing the linear actuator when the overload retry counter is less than the overload retry threshold and maintaining de-energizing of the linear actuator when the overload retry counter is at least

Abstract: A stator phase circuit for an electric machine includes a phase winding circuit including a plurality of series coupled sub-winding circuits, each sub-winding circuit includes a respective sub-winding coupled in parallel across a respective first controllable switch.

Abstract: A field coil segment for an electric machine including a rotor and a stator includes a first wire element having a first cross sectional area electrically connected in parallel with a second wire element having a second cross sectional area greater than the first cross sectional area.

Abstract: A stator phase circuit for an electric machine includes a phase winding circuit including a plurality of series coupled sub-winding circuits, each sub-winding circuit includes a respective sub-winding coupled in parallel across a respective first controllable switch.

Abstract: A generator system that includes a six-phase AC machine and an active rectifier bridge employing low on-resistance switches, such as MOSFET switches, for converting the AC current from the machine to a DC current. The system also includes a switch control circuit to switch the MOSFET switches in synchronization with the six-phase current flow. The system determines the phase-to-ground voltages of the machine for inputs to the switch control circuit. The control circuit calculates the phase-to-phase voltages from the phase-to-ground voltages. The control circuit uses a specific control scheme to determine if each of the phase-to-phase voltages is above or below first and second predetermined threshold voltages, where if the phase-to-phase voltage is above the first threshold voltage, the control circuit closes the switch, and if the phase-to-phase voltage is below the second threshold voltage, the control circuit opens the switch.

Abstract: A system and method may identifying an overcharged cell from among a plurality of cells of a battery pack. An undercharged cell may be identified from among any of the plurality of cells of the battery pack. A switch may be operated to connect the overcharged cell to the undercharged cell via a direct current (DC)-DC converter. The DC-DC converter may be operated to transfer charge from the overcharged cell to the undercharged cell.

Abstract: An equivalent power method for reducing the effects of voltage variation during at least one active material actuation event, includes determining an applied real output based on the ideal voltage of a voltage source, the corresponding ideal output of a controller, and a measured real voltage, and for providing voltage out of bounds compensation, by further determining a difference based on the maximum available power output of the controller during said at least one event, and applying the difference to determine the applied real output during subsequent event(s).

Abstract: A linear actuator associated with an actuator system for a device includes a wire cable fabricated from an active material. The linear actuator couples to the device and to the moveable element. The active material induces strain in the linear actuator in response to an activation signal. The linear actuator translates the moveable element relative to the device in response to the induced strain. An activation controller electrically connects to the linear actuator and generates the activation signal. A position feedback sensor monitors a position of the moveable element.

Abstract: A system for and method of reducing the effects of preheat period variation in shape memory alloy actuation, include sensing the removal of motion delay due to slack, backlash, and/or compliance in the actuator and drive-train of the system, and determining actuator activation, as a result thereof.

Abstract: A field coil segment for an electric machine including a rotor and a stator includes a first wire element having a first cross sectional area electrically connected in parallel with a second wire element having a second cross sectional area greater than the first cross sectional area.

Abstract: A method for determining a temperature of an electric motor including stator windings includes injecting an AC current into a D-axis current of a stator winding at a frequency that is synchronized with a control frequency of the electric motor, determining a DC-phase current, determining a resistance of the stator winding corresponding to the DC-phase current and an applied voltage, and determining a temperature of the electric motor as a function of the resistance of the stator winding.

Abstract: A stator phase circuit for an electric machine includes a phase winding circuit including a plurality of series coupled sub-winding circuits, each sub-winding circuit includes a respective sub-winding coupled in parallel across a respective first controllable switch.

Abstract: A method of controlling and/or predicting the remaining useful life of an active material actuator, such as a shape memory alloy wire, includes obtaining historical actuation data of an inherent system variable, such as electrical resistance, over a secondary variable, such as time, determining a normal operating envelope having upper and lower bounds based on the data, determining a current profile for a given actuation cycle, and comparing the shape of the current profile to the envelope to determine an out-of-bounds event.

Abstract: A permanent magnet electric machine drive system that includes a plurality of magnets for generating a first magnetic field and a stator is disposed radially outward from the plurality of magnets for generating a magnetic field. The stator includes a plurality of stator poles separated by slots with each respective stator pole having a concentrated winding with a respective number of turns formed around each respective stator pole. Each respective concentrated winding within the stator comprising non-overlapping phases. The concentrated windings form a dual three-phase winding configuration that includes a first set of three-balanced phase windings and a second set of three-balanced phase windings. The first set of three-balanced phase windings is phase shifted in the range of 15 to 45 electrical degrees from the second set of three-balanced phase windings for reducing the torque ripple.

Abstract: An on-vehicle DC/DC converter transforms high-voltage electric power originating from an on-vehicle high-voltage source to low-voltage electric power at a regulated voltage level. The low-voltage electric power is distributed by a low-voltage bus. A method for operating the DC/DC converter includes monitoring a state of charge and a temperature of a low-voltage battery connected to the low-voltage bus, setting a DC/DC converter command to a nominal voltage level as a function of the state of charge and temperature of the low-voltage battery, monitoring a total low-voltage electric load, and adjusting the DC/DC converter command to a minimum low-voltage reference voltage when the vehicle is operating below a predetermined speed and the total low-voltage electric load is greater than a predetermined load.

Abstract: An active material actuator adapted for use in a circuit includes an active material member, and a piezoelectric or piezoresistive element or otherwise force sensing device, wherein the element or device is communicatively coupled to the member and operable to vary the current within the circuit when the member is caused to achieve a predetermined stress, such that, in one aspect, the element presents an overload protection mechanism.