David H Perreault

US Patent:

6346797, Feb 12, 2002

Filed:

Apr 26, 2000

Appl. No.:

09/557844

Inventors:

David J. Perreault - Brookline MA
Vahe Caliskan - Cambridge MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H02P 910

US Classification:

322 29, 322 28, 322 36

Abstract:

An alternator system having an ac machine includes a switched-mode rectifier operating at a duty cycle selected based upon at least one of the emf, frequency or speed of operation of the ac machine. The switched-mode rectifier operates such that the alternator system provides a load match which results in output power levels which are relatively high compared with output power levels of conventional alternator systems.

US Patent:

6456514, Sep 24, 2002

Filed:

Apr 26, 2000

Appl. No.:

09/558193

Inventors:

David J. Perreault - Brookline MA
Vahe Caliskan - Cambridge MA

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H02M 542

US Classification:

363 89

Abstract:

A system for charging a first source from a second source includes an alternating current (ac) voltage source having an internal inductance, a switching power converter coupled to the ac voltage source and the first source, a control circuit coupled to the switching power converter, a connecting system for selectively connecting a positive terminal of the second source to the ac voltage source and a jump charging controller coupled to the control circuit and operative to enable the switching power converter to be used in conjunction with the ac voltage source inductances as a dc/dc converter to charge the first source from the second source.

US Patent:

6551233, Apr 22, 2003

Filed:

Aug 8, 2001

Appl. No.:

09/924907

Inventors:

David J. Perreault - Brookline MA
Scott Mogren - Holliston MA

Assignee:

R. B. Carr Engineering, Onc. - Newton MA

International Classification:

A61N 200

US Classification:

600 9, 324657, 324673

Abstract:

An electromagnetic stimulator circuit has a precharge power supply, a capacitor, a set of switches, and a stimulator coil. The switches, which can be implemented using a variety of devices, enable flexible control over the coil current waveform without requiring the physical reconfiguration of circuit elements. The shape of the output current pulse is controlled by the modulation of the switches, and much of the energy applied to the coil is returned from the coil to the capacitor for reuse on the succeeding pulse. Less power is required and less heat energy is generated.

US Patent:

6671195, Dec 30, 2003

Filed:

May 6, 2002

Appl. No.:

10/139710

Inventors:

David J. Perreault - Brookline MA
Vahe Caliskan - Chicago IL

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H02M 542

US Classification:

363 89, 361 88

Abstract:

An alternator system having an alternating current voltage source includes a rectifier coupled to the voltage source, a sensor coupled to the voltage source and an engine and a control circuit coupled to the voltage source, the rectifier and the sensor. The control circuit provides control signals to the rectifier and the voltage source. The alternator system further includes a fault protection controller coupled to an output of the alternator system and coupled to the control circuit. The rectifier operates such that the alternator system provides a load match which results in output power levels which are relatively high compared with output power levels of conventional alternator systems and the fault protection controller operates under fault conditions (e. g. load dump), and overrides the other controllers in the alternator system based on output voltage when a load dump occurs.

US Patent:

6900997, May 31, 2005

Filed:

Jun 23, 2003

Appl. No.:

10/601366

Inventors:

David J. Perreault - Brookline MA, US
Vahe Caliskan - Chicago IL, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H02M007/217

US Classification:

363127

Abstract:

An alternator system having an alternating current voltage source includes a rectifier coupled to the voltage source, a sensor coupled to the voltage source and an engine and a control circuit coupled to the voltage source, the rectifier and the sensor. The control circuit provides control signals to the rectifier and the voltage source. The alternator system further includes a fault protection controller coupled to an output of the alternator system and coupled to the control circuit. The rectifier operates such that the alternator system provides a load match which results in output power levels which are relatively high compared with output power levels of conventional alternator systems and the fault protection controller operates under fault conditions (e. g. load dump), and overrides the other controllers in the alternator system based on output voltage when a load dump occurs.

US Patent:

6912142, Jun 28, 2005

Filed:

Oct 22, 2001

Appl. No.:

10/086069

Inventors:

Thomas A. Keim - Boxborough MA, US
David J. Perreault - Brookline MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H02M005/42

US Classification:

363 89

Abstract:

An alternator system having an alternating current (ac) voltage source includes a switched-mode rectifier (SMR) coupled to the ac voltage source and having an output port coupled to an output of the alternator system, and a controller coupled to said switched-mode rectifier so as to provide a controlled pulse sequence synchronized with an angular rotor position of the (ac) voltage source to activate and deactivate the switched-mode rectifier. The controller further includes a PWM generator having a first input to receive a total duty ratio signal synchronized with an angular rotor position of the (ac) voltage source. The switched mode rectifiers are controlled to increase power output levels at lower speeds near idle. The controller combines improved idle speed power output levels with load matching improvements from PWM control for more efficient operation when compared to circuits using conventional control or PWM load matching control alone.

US Patent:

6937115, Aug 30, 2005

Filed:

Feb 25, 2002

Appl. No.:

10/082616

Inventors:

David J. Perreault - Brookline MA, US
Joshua W. Phinney - Somerville MA, US
Timothy C. Neugebauer - Cambridge MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H03H007/01

US Classification:

333177, 333172

Abstract:

An electrical component includes a capacitive impedance and a shunt path inductance cancellation feature provided by coupled windings. A filter having a capacitor with capacitor-path inductance cancellation provides enhanced performance over frequency compared with conventional capacitors.

US Patent:

7242269, Jul 10, 2007

Filed:

May 2, 2005

Appl. No.:

11/119659

Inventors:

David J. Perreault - Brookline MA, US
Timothy C. Neugebauer - Cambridge MA, US
Joshua W. Phinney - Glen Oaks NY, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H03H 7/01
H03H 7/00

US Classification:

333177, 333172

Abstract:

An electrical component includes a capacitive impedance and a shunt path inductance cancellation feature provided by coupled windings. A filter having a capacitor with capacitor-path inductance cancellation provides enhanced performance over frequency compared with conventional capacitors.