Ford Motor Company Limited

Ballard Power Systems Corporation

Ford Global Technolgoies, LLC

Ford Global Tech.inc

Ecostar Electric Drive Systems L.l.c.

Siemens Vdo Automotive Corporation

Doug D Deng

Kon-King Mike Wang

Xingyi Xu

Jack H Xu

Kenneth James Farkas

Kent Michael Harmon

Mukunda V Prema

Dumitru Raceu

Steven J Kowalec

Vijay Bhavaraju

Christos Aristotles Kambouris

A hybrid use of a phase-locked-loop controller and a microprocessor-based controller to synchronize the phase angles of a three-phase AC power source, such as a static power converter, with those of a three-phase power grid. The phase-angle synchronization may enable the AC power source to be safely connected to the power grid to provide additional power capacity.

Hybrid synchronization phase angle generation method

The present invention relates to a system and method for compensating the voltage distortion and minimizing the available voltage range loss both caused by switching dead-time of solid-state switch components in power conversion devices. As a result, the power quality supplied from the power conversion devices can be improved and the output voltage of such devices can be increased.

Dead-time compensation with narrow pulse elimination in solid- state switch devices

A power conversion system which comprises a controller and conversion assemblies which selectively rectify and invert an electrical signal. Conversion assemblies respectively comprise a plurality of integrated gate bipolar transistor assemblies. The power conversion system is effective to convert DC current to AC current, convert AC current to DC current, and to control the output frequency of a received electrical signal to a conventional operating range.

Power converter system

A method and system for detecting the negative sequence of three phase grid-connected inverter systems utilizes, for example, computer hardware and/or computer software to remove a direct current component from a direct-axis current feedback for a three phase current of the inverter system to yield a pure alternating current waveform signal. A first low pass filter eliminates high frequency noise from the alternating current waveform signal while passing a negative sequence signal. The filtered signal is rectified to an absolute value, and a second low pass filter flattens the rectified signal to an output signal that is indicative of the magnitude of the negative sequence current.

Method and system for detecting a negative sequence for three phase grid-connected inverter systems

A system for synchronizing the phase angle of an alternating current power source (&ldquo;APS&rdquo;) with the phase angle of a power grid . The system provides for reliable synchronization between the phase angle of the APS and the phase angle of the power grid during both normal and abnormal operating conditions.

System and method for synchronizing the phase angle for an AC power source in parallel operation with a grid

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

A system (,) and method (,) for connecting and synchronizing a supplemental power supply (,) and a power grid. The present invention detects current feedback signals i,and i,and grid phase voltage input signals U,, U,, and U,for controlling and synchronizing the three-phase output voltages U,, U,, and U,, of the supplemental power supply (,) with the power grid. The method (,) of the present invention detects the three-phase voltages of both the supplemental power supply, U,, U,, U,and the power grid U,, U,, U,, and converts the detected voltages into components U,, U,on a d-q plane.

System for connecting and synchronizing a supplemental power source to a power grid

An inverter circuit (,) has a plurality of voltage source inverters (VSI) coupled in parallel. Each of the voltage source inverters are coupled to a load (,). A synch signal source (,) generates a square wave from a fundamental operating frequency. The square wave generated by the synch signal source (,) is coupled to each voltage source inverter (VSI). Each voltage source inverter VSI has a timer counter (,), a microprocessor (,), and an inverter (,). The timer counter (,) is preferably a triangle wave generator that corresponds to the time since a rising edge of a synch signal (,) The microprocessor (,) samples the cyclic output signal (,) and determines a phase angle for the voltage source inverter. The phase angle and the voltage magnitude are provided to the inverter (,). The inverter (,) provides an output signal to the load that has the same phase angle as the outputs of the other phase inverters.

Method and circuit for synchronizing parallel voltage source inverters

A method for transmitting phase angle information between inverters in a parallel connected inverter system to synchronize the phase angles of the inverters includes transmitting a common phase angle signal to server inverters. The common phase angle signal is a function of the phase angle of a master inverter. The common phase angle signal is indicative of the absolute phase angle of the master inverter when the phase angle of the master inverter is equal to a phase angle value associated with a new phase cycle. The common phase angle signal is indicative of an incremental phase angle change of the phase angle of the master inverter in a given time period while the phase angle of the master inverter is different from the value associated with a new phase cycle. The server inverters control their phase angles in accordance with the common phase angle signal such that the phase angles of the master inverter and the server inverters are synchronized.

Method and system for synchronizing the phase angles of parallel connected inverters

A method for controlling regenerative energy in a system having an motor and having a power converter for converting regenerative energy from the motor for supply as electrical current to a receiving apparatus includes estimating a resistance to electrical current flow between the electrical power converter and the receiving apparatus and measuring a first voltage at the receiving apparatus. The method further comprises controlling a regenerative current from the power converter to the receiving apparatus in view of the resistance and the first voltage to limit a second voltage at the power converter.

Voltage control method for an electric motor control system

The present invention provides a method for reducing torsional vibration in a vehicle drivetrain. The method comprises detecting a rotational speed of the drivetrain to generate a rotational speed signal. The method also includes generating a vibration compensating torque command which is a function of a frequency content of the rotational speed signal. The present invention further provides a system for reducing torsional vibration in a vehicle drivetrain. The system includes a source of torque, a drivetrain coupled to receive torque from the source of torque and a speed detector adapted to detect a rotational speed of the drivetrain and generate a rotational speed signal. The system additionally includes an electronic controller coupled to the source of torque and programmed to provide operational command signals to the source of torque. The system further comprises a frequency detector having an input and an output, the input coupled in electrical communication with the speed detector to receive the rotational speed signal and the output coupled in electrical communication with the electronic controller.

Torsional oscillation compensation in the drivetrain of a motor 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.

Backlash elimination in the drivetrain of an electric vehicle

An induction motor control system for electric vehicles having a DC power supply, an inverter, and an induction motor, includes a current control mechanism having a flux controller. The flux controller reduces the stator flux to improve the torque output of a motor at the limit of the voltage supply from the inverter. The reduction in flux is adjustable as the actual limit of voltage available to power the motor varies. A flux reference .lambda..sub.so generated according to efficiency control requirements can be adjusted by a flux weakening quantity generated by the controller in the constant power range of operation. The DC bus voltage, the rotor speed and stator flux reference values are input to the flux controller so that the motor can be operated to achieve improved torque output approaching the theoretical maximum torque output or to maximize efficiency as needed. In addition, the flux control influences generation of a stator current that improves the torque output throughout the entire range of motor speed.

Induction motor drive controller

In one embodiment of the present invention, a control method for an induction motor includes calculating a desired quadrature-axis voltage and a desired direct-axis voltage according to both current control and voltage control. Below a predetermined motor speed, the motor is controlled in accordance with current control only. Above that predetermined speed, the two desired quadrature-axis voltages are combined in relative proportions, with the influence of voltage control being greater with higher motor speed. The two desired direct-axis voltages are likewise combined. The influence of voltage control thus increases with increasing motor speed. Above a second motor speed threshold, the motor is controlled in accordance with voltage control only.

Induction motor control method

When negative times are calculated for zero space vectors of a SVPWM controlled three phase inverter circuit, the zero vector times are set to zero, the non-zero space vector closer to a commanded space vector is preserved, and the non-zero space vector farther from the commanded space vector is truncated. Thus, control of the inverter circuit seamlessly transits from SVPWM to full six step operation. In one arrangement, for each negative calculated zero space vector time, the larger of the non-zero space vector times is set to the minimum of its calculated time and the pulse width modulation control period (TPWM), and the smaller of the calculated non-zero space vector times is set equal to TPWM less the set value of the larger of the non-zero space vector times. In another arrangement, each negative calculated zero space vector time is algebraically combined with the smaller of the non-zero space vector times. If the resulting non-zero space vector time is greater than or equal to zero, it is used together with the calculated time for the larger of the non-zero space vectors. If the resulting non-zero space vector time is less than zero, the time for the larger of the non-zero space vectors is set to TPWM and the time for the smaller of the non-zero space vectors is set to zero. For both of these arrangements, the zero space vector time is set to zero.

Growing community of inventors

Canton, MI, United States of America

Doug D Deng