James D Walters

US Patent:

6407531, Jun 18, 2002

Filed:

Jan 9, 2001

Appl. No.:

09/757187

Inventors:

James E. Walters - Carmel IN
Fani S. Gunawan - Westfield IN
Yanhong Xue - Westfield IN

Assignee:

Delphi Technologies, Inc. - Troy MI

International Classification:

H02P 700

US Classification:

318805, 318807

Abstract:

System and method for controlling a synchronous machine are provided. The method allows for calculating a stator voltage index. The method further allows for relating the magnitude of the stator voltage index against a threshold voltage value. An offset signal is generated based on the results of the relating step. A respective state of operation of the machine is determined. The offset signal is processed based on the respective state of the machine.

US Patent:

6565479, May 20, 2003

Filed:

Jul 5, 2001

Appl. No.:

09/899725

Inventors:

Gerald Thomas Fattic - Fishers IN
James E. Walters - Carmel IN
Michael Scott Sullivan - Noblesville IN

Assignee:

Delphi Technologies, Inc. - Troy MI

International Classification:

B60K 102

US Classification:

477 3

Abstract:

A method for and apparatus for preventing oscillations of a vehicle. The engine speed is monitored and filtered, the filtered engine speed being compared to a natural frequency of the vehicle. The natural frequency corresponds to a gear ratio of the vehicle. A torque command is provided to an electric machine coupled to a driveline of the vehicle, the electric machine provides a counteracting torque to the driveline in order to eliminate oscillations in the vehicle.

US Patent:

6566830, May 20, 2003

Filed:

Aug 17, 2001

Appl. No.:

09/932602

Inventors:

James E. Walters - Carmel IN

Assignee:

Delphi Technologies, Inc. - Troy MI

International Classification:

H02P 100

US Classification:

318445, 318431, 318720, 318799

Abstract:

Method and system for controlling the start of a permanent magnet machine are provided. The method allows to assign a parameter value indicative of an estimated initial rotor position of the machine. The method further allows to energize the machine with a level of current being sufficiently high to start rotor motion in a desired direction in the event the initial rotor position estimate is sufficiently close to the actual rotor position of the machine. A sensing action allows to sense whether any incremental changes in rotor position occur in response to the energizing action. In the event no changes in rotor position are sensed, the method allows to incrementally adjust the estimated rotor position by a first set of angular values until changes in rotor position are sensed. In the event changes in rotor position are sensed, the method allows to provide a rotor alignment signal as rotor motion continues. The alignment signal allows to align the estimated rotor position relative to the actual rotor position.

US Patent:

6590361, Jul 8, 2003

Filed:

Jul 19, 2001

Appl. No.:

09/909356

Inventors:

James E. Walters - Carmel IN
Fani S. Gunawan - Westfield IN
Gerald Thomas Fattic - Fishers IN

Assignee:

Delphi Technologies, Inc. - Troy MI

International Classification:

H02P 142

US Classification:

318727, 318804, 318805, 318806, 318807, 318808, 318809, 318810, 318811

Abstract:

Method and system for controlling an induction machine are provided. The method allows to sense rotor position of the induction machine using a relatively low-resolution rotor position sensor configured to supply a stream of pulses indicative of angular increments as the rotor position changes. A memory device is used for storing a synchronous angle boost function. The method further allows to retrieve from the memory device at least one function parameter for providing a synchronous angle boost during a start up mode of operation of the induction machine. Upon sensing a predetermined number of pulses from the rotor position sensor, the method allows to switch from the start up mode of operation to a normal mode of operation, wherein the boost provided to the synchronous angle is discontinued upon switching to the normal mode of operation.

US Patent:

6639371, Oct 28, 2003

Filed:

Aug 17, 2001

Appl. No.:

09/932197

Inventors:

James E. Walters - Carmel IN
Ronald John Krefta - Noblesville IN

Assignee:

Delphi Technologies, Inc. - Troy MI

International Classification:

H02K 2300

US Classification:

318254, 318430, 318439, 318138, 290 40 R, 290 51

Abstract:

Method and system for controlling a permanent magnet machine are provided. The method provides a sensor assembly for sensing rotor sector position relative to a plurality of angular sectors. The method further provides a sensor for sensing angular increments in rotor position. The method allows starting the machine in a brushless direct current mode of operation using a calculated initial rotor position based on an initial angular sector position information from the sensor assembly. Upon determining a transition from the initial angular sector to the next angular sector, the method allows switching to a sinusoidal mode of operation using rotor position based on rotor position information from the incremental sensor.

US Patent:

6741060, May 25, 2004

Filed:

Apr 5, 2001

Appl. No.:

09/827052

Inventors:

Ronald John Krefta - Noblesville IN
James E. Walters - Carmel IN
Fani S. Gunawan - Westfield IN

Assignee:

Delphi Technologies, Inc. - Troy MI

International Classification:

H02P 124

US Classification:

318727

Abstract:

Method and system for controlling a permanent magnet machine driven by an inverter is provided. The method allows for monitoring a signal indicative of a fault condition. The method further allows for generating during the fault condition a respective signal configured to maintain a field weakening current even though electrical power from an energy source is absent during said fault condition. The level of the maintained field-weakening current enables the machine to operate in a safe mode so that the inverter is protected from excess voltage.

US Patent:

6774592, Aug 10, 2004

Filed:

Dec 3, 2001

Appl. No.:

10/007793

Inventors:

James E. Walters - Carmel IN
John Derek Williams - New Palestine IN

Assignee:

Delphi Technologies, Inc. - Troy MI

International Classification:

H02K 2300

US Classification:

318254, 318138, 318430, 318431, 318439, 318700, 318720, 318721, 318722, 318723, 318724

Abstract:

Method and system for controlling a permanent magnet machine are provided. The method provides a sensor assembly for sensing rotor sector position relative to a plurality of angular sectors. The method allows starting the machine in a brushless direct current mode of operation using a calculated initial rotor position based on angular sector position information from the sensor assembly. Upon reaching a predefined mode-crossover criterion, the method allows switching to a sinusoidal mode of operation using rotor angle position based on extrapolating angular sector position information from the sensor assembly.

US Patent:

7026776, Apr 11, 2006

Filed:

Jun 30, 2005

Appl. No.:

11/171664

Inventors:

James E. Walters - Carmel IN, US

Assignee:

Delphi Technologies, Inc. - Troy MI

International Classification:

H02K 17/32

US Classification:

318434, 318430, 318432, 318433

Abstract:

The invention provides a method for controlling current in a direct current motor having a back emf constant (k), which may be a function of field current if the direct current motor is a field wound machine, and motor resistance (R) in all 4 quadrants of operation. The method includes the step of rotating a motor shaft of the direct current motor with a controller by applying a first voltage across the direct current motor's terminals. The first voltage corresponds to a first value of current passing through the armature windings of the direct current motor. The method also includes the step of determining a maximum value of current to pass through the armature windings of the direct current motor. The maximum value of current is selected to prevent undesirable over current conditions, such as thermal overload as one example. The method also includes the step of receiving a signal corresponding to a desired motor speed (ω*) with the controller during the rotating step.