Ford Global Technolgoies, LLC

Rimma Isayeva

Balakrishna Rao

Jonathan Andrew Butcher

Daniel Richard Luedtke

Michael W Degner

William Reynolds

David Crist Gabriel

Hongjie Wu

Yuqing Tang

Liwen Xu

Daniel R Parks

Chang-jiang Wang

A vehicle is provided including an electric machine and at least one controller. The controller, or controllers, are configured to, in response to a reset of the at least one controller while a speed of the vehicle is greater than a threshold value, provide a current command to the electric machine in accordance with calibration values calculated prior to the reset such that inoperability of the electric machine due to the reset is less than one second.

Control strategy for an electric machine in a vehicle

A vehicle having at least two electric machines includes an oil circulation path that circulates oil through the electric machines. A controller commands the electric machines to fulfill torque demands. The controller utilizes the oil temperature in the oil circulation path to control the commanded torque output by the electric machines. In the event of a failure or fault in an oil temperature sensor, the controller estimates the oil temperature from the temperature of coils within at least one of the electric machines. The estimated oil temperature is utilized instead of the sensed oil temperature to control the torque outputs to satisfy torque demands.

Temperature based electric machine control

A vehicle includes at least one electric machine and an inverter for selectively transmitting power to the electric machine. The inverter includes a power module. At least one controller controls the electric machine and the inverter. The controller at least temporarily disables the inverter during a power cycle such that power to the electric machine is inhibited. In response to the disabling of the inverter, the controller resets the duty cycle commands for the power module, and re-enables the inverter during the same power cycle.

Vehicle electric machine control strategy

A method for operating a hybrid electric vehicle having a variable voltage converter (VVC) includes commanding a first voltage across a VVC in response to a signal requesting a VVC test, continuously monitoring a first VVC voltage difference over a first calibratable time period, and generating a diagnostic signal if the first voltage difference exceeds a first calibratable threshold for the duration of a first calibratable time period. The method further includes, in response to the first voltage difference dropping below the first calibratable threshold, commanding a second voltage across the VVC, continuously monitoring a second VVC voltage difference over a second calibratable time period, generating a diagnostic signal if the second voltage difference exceeds a second calibratable threshold for the duration of a second calibratable time period, and signaling a test pass in response to the second voltage difference dropping below the second calibratable threshold.

Hybrid electric vehicle power-up sequencing with VVC test

Systems, apparatus, and methods detect a current sensor error in an FOC electric machine system. A voltage command is monitored to detect the presence of an ac component that indicates that an error has occurred at a current sensor. For example, a sensor fault detection module can be configured to determine the deviation between an actual voltage command and an ideal voltage command to provide a complex deviation vector. By transforming the deviation vector to a reference frame rotating at the fundamental frequency of the command voltage, a dc component of the positive and negative sequences can be filtered, and their amplitudes determined. Error detection can be based on the total amplitude of the fundamental component, determined by positive and negative component amplitudes. Sensor error detection enables an FOC system to operate with two current sensors, rather than three, and provides a dedicated fault diagnostic for a current sensor.

Detection method of current sensor faults in the e-drive system by using the voltage command error

A vehicle having at least one electric machine capable of propelling the vehicle is provided. An oil circulation path is provided that circulates oil through the electric machines. A controller commands the electric machines to fulfill torque demands. The controller utilizes the oil temperature in the oil circulation path in order to control the commanded torque output by the electric machines. In the event of a failure or fault in the oil temperature sensors, the controller estimates the oil temperature from the temperature of coils within the electric machine. The estimated oil temperature is utilized instead of the sensed oil temperature to control the torque outputs to maintain torque demands.

A hybrid-electric vehicle and method of controlling a hybrid-vehicle is provided. The vehicle includes a traction battery, at least one electric-machine, and a controller. The controller is configured to alter a voltage between the battery and the electric-machine based on a measured voltage of the battery or the high voltage bus. In response to an indication that the measured voltage is faulty during a drive cycle, the controller instead alters the voltage between the battery and the electric machine based on a substituted battery voltage signal such that the electric-machine remains operable for the drive cycle.

A hybrid-electric vehicle method of controlling a hybrid electric vehicle is provided. The vehicle includes a traction battery, at least two electric-machines, and a controller. The controller is configured to, in response to a faulted condition one of the electric-machines during a drive cycle, command the other of the electric-machines to function in a mode in which torque output is restricted to a threshold value that depends on a voltage of the battery to maintain vehicle propulsion during the drive cycle.

A system and method for controlling an electric vehicle include at least one controller configured to detect an over-voltage condition when an electric-machine voltage exceeds an over-voltage threshold. In response to the over-voltage condition, the electric machine and a variable voltage controller (VVC) are disabled. Upon determining the electric-machine voltage is decreased to at least a second threshold being less than the over-voltage threshold, the controller is configured to set the VVC to a limited-operation mode. Upon determining the electric-machine voltage is decreased to at least a third threshold being less than the second threshold and the over-voltage threshold, the controller is configured to re-enable the electric machine and set the VVC to a normal-operation mode. The limited operation-mode enables the vehicle to maintain vehicle propulsion during the drive-cycle as the electric machine is recovered from a transient condition causing the over-voltage condition.

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Farmington Hills, MI, United States of America

Rimma Isayeva