Ford Motor Company Limited

Continental Automotive Systems Us, Inc.

Ballard Power Systems Corporation

Ecostar Electric Drive Systems L.l.c.

Ford Global Technolgoies, LLC

Kenneth James Farkas

Duo Deng

Jack H Xu

Kerry Eden Grand

Anil Tuladhar

Doug D Deng

Vinod Reddy

Mukunda V Prema

Cycle error correction is performed in an electronic power system to compensate for a difference between an AC grid side frequency and an AC load side frequency. The electronic power system can comprise an electronic power inverter, such as one usable with an uninterruptible power supply. Cycles of signals indicative of the AC grid power and the AC load power are counted and compared to obtain a cycle error value. If the cycle error value exceeds a first value to indicate that AC load side frequency is too high or too low, then compensation is performed to change the AC load side frequency to be closer to the AC grid side frequency. If the cycle error value falls below a second value to indicate that the AC grid side frequency and AC load side frequency are sufficiently close to one another, then the compensation is deactivated.

Method and apparatus for cycle error correction for a power converter device, such as an electronic power inverter

An encoder failure detector system and method for detecting failure of an encoder during time periods when a zero rotational speed is expected. For example, in one embodiment a test signal is applied during a period when a zero rotational speed is expected and a failure is indicated if no movement of a rotor is detected in response to the test signal.

System and method for encoder failure detection

Cycle error correction is performed in an electronic power system to compensate for a difference between an AC grid side frequency and an AC load side frequency. The electronic power system includes an electronic power inverter, such as one usable with an uninterruptible power supply. Cycles of signals indicative of the AC grid power and the AC load power are counted and compared to obtain a cycle error value. If the cycle error value exceeds a first value to indicate that AC load side frequency is too high or too low, then compensation is performed to change the AC load side frequency to be closer to the AC grid side frequency. If the cycle error value falls below a second value to indicate that the AC grid side frequency and AC load side frequency are sufficiently close to one another, then the compensation is deactivated.

A power system employs an outer voltage feedback loop and an inner current feedback loop to control a power converter, such as a DC to AC inverter for transferring electrical power between a power source, for example a photovoltaic array, and a load, for example a power grid. The outer loop accommodates variations in the output of the power source, for example accommodating anomalies in IV characteristics such as IV droop characteristic associated with photovoltaic cells. The outer loop may employ a first control regime or a second control regime, for example, dependent on whether a DC bus voltage or power is smaller than a value corresponding to measurement resolution or expected noise.

Method and apparatus for tracking maximum power point for inverters, for example, in photovoltaic applications

System and method for controlling the output torque of an electrical machine include a torque controller operable for receiving a motor input command, representative of a desired output torque, and generating a drive command to direct a motor to produce a predetermined output torque based on the motor input command. Further, the torque controller may include a sensor system for generating a feedback signal representative of an actual output torque of the motor. Additionally, the torque controller includes an input modulator and a speed modulator for adjusting the drive command based on the feedback signal and based on the motor input command to control a value of the predetermined output torque and to control a rate at which the predetermined output torque reaches the desired output torque.

System and method for controlling torque in an electrical machine

This invention provides a process for determining a desired torque (load) value for a load-dependent current generating system, such as a fuel cell system, in an electric vehicle. The process calculates load based on various driver demands such as accelerator position, brake position, Key on/off, Gear selector position, and system component temperatures. Additionally, the process considers the amount of current available from the load-dependent current generating system and matches that current to the current drawn by the electric motor. The process can be applied to a direct current (DC) electric traction motor or an alternating current (AC) induction motor.

Method of current interaction in an electric motor drive system having a load-dependent current generating system

An error detection method for use with a two channel increment encoder. The error detection method operates to detect errors over a wide range of rotational velocity of a rotating member. The error detection method employs the signal from one or two of the channels of the encoder and determines if pulse edges from the signals deviate from expected normal behavior. When an error is detected, actions can then be taken by the controller for the rotating member to prevent undesired results.

Increment encoder failure detection

An induction motor control system (,) for electric vehicles having a DC power supply (,), an inverter (,), an induction motor (,), and a clamping unit (,). The clamping unit (,) applies a clamping value iq_clamp to a real torque current command i,*. The clamping value iq_clamp is calculated in a maximum torque current calculation unit,and is based on predetermined maximum settings for the motor power P,and torque T,. The clamping value iq_clamp is applied such that the torque current command i,* cannot exceed the clamping value iq_clamp, whereby the induction motor produces,output power P,and torque T,that is always less than the predetermined maximum settings, P,and T,.

Induction motor power/torque clamping for electric vehicle performance

The present invention provides vibration control for a vehicle drivetrain. In one embodiment of the present invention, a vibration control method comprises generating a speed signal representing a rotational speed of the drivetrain. The method further includes half-wave rectifying the speed signal to generate a first signal. Also, the method comprises inverting the speed signal and half-wave rectifying the inverted signal to generate a second signal. Also, the method includes low-pass filtering the first signal to generate a third signal and low-pass filtering the second signal to generate a fourth signal. In addition, the method comprises selecting a minimum of the third and fourth signals to generate a fifth signal.

Vibration detection and control for a vehicle drivetrain

A method of controlling electric motor torque in an electric vehicle for improved vehicle performance and energy conservation includes receiving a throttle torque request and a brake torque request, and sensing the speed of the vehicle. The brake torque request is split into a creep cancellation component and a brake regenerative component. The throttle torque request is adjusted based upon the creep cancellation component and the brake regenerative component to produce a torque sum. The electric motor torque is then controlled based upon the torque sum.

Method of controlling electric motor torque in an electric vehicle

The present invention provides a method for substantially eliminating backlash in drivetrain gears of a vehicle propelled by an electric motor. The method includes detecting whether brakes of the vehicle are applied. The method further comprises only if the brakes are applied, applying a torque from the electric motor to move at least some teeth of the gears into contact with one another. The present invention further provides a system for substantially eliminating backlash in a drivetrain of a motor vehicle. In one embodiment, the system comprises a plurality of wheels and a drivetrain coupled to at least one of said wheels and comprising engaging gears. The embodiment also includes brakes proximate to at least one of the wheels and adapted to selectively apply braking torque to the at least one of the wheels to which the brakes are proximate. Additionally, the embodiment comprises an electric motor coupled to the drivetrain for applying a torque only while the brakes are applied to move at least the teeth of the gears into contact with one another.

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Dearborn, MI, United States of America

Kenneth James Farkas