David L Perreault

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:

20020089866, Jul 11, 2002

Filed:

Oct 22, 2001

Appl. No.:

10/080819

Inventors:

Thomas Keim - Boxborough MA, US
David Perreault - Brookline MA, US

International Classification:

H02M005/42

US Classification:

363/089000

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:

49374141, Jun 26, 1990

Filed:

Sep 12, 1988

Appl. No.:

7/242996

Inventors:

David J. Perreault - Exeter NH
Arun K. Chaudhuri - Florence SC
Roy White - Exeter NH
Richard A. Harris - Hampton Falls NH

International Classification:

B23H 710
B28B 1112

US Classification:

219 6912

Abstract:

A wire guide for EDM machining apparatus comprises a vacuum hot pressed titanium diboride block having a groove on a curved side of the block for positioning EDM wire. The block has a mounting hole therethrough lined with an electrically insulating sleeve.

US Patent:

20190006995, Jan 3, 2019

Filed:

Sep 10, 2018

Appl. No.:

16/126553

Inventors:

- Cambridge MA, US
David J. Perreault - Andover MA, US

International Classification:

H03F 1/02
H03H 7/38
H03F 3/24
H03F 1/56
H03F 3/217
H03F 3/21
H03F 3/19
H03F 3/193

Abstract:

Described are concepts, systems, circuits and techniques directed toward methods and apparatus for generating one or more pulse width modulated (PWM) waveforms with the ability to dynamically control pulse width and phase with respect to a reference signal.

US Patent:

20170373609, Dec 28, 2017

Filed:

Jun 28, 2017

Appl. No.:

15/635896

Inventors:

- Cambridge MA, US
David J. Perreault - Andover MA, US

International Classification:

H02M 7/493
H02M 1/08
H02M 1/00
H02M 7/48

Abstract:

Inverter systems, circuits and associated control techniques for providing efficient delivery of high-frequency (HF) power and radio-frequency (RF) power into variable load impedances while maintaining resistive/inductive loading of the constituent inverters for zero voltage switching (ZVS) are described. The inverter architecture and associated control techniques for providing efficient delivery of HF into variable load impedances includes a first inverter having an output coupled to an input of an immittance converter. An output of the immittance converter is coupled to a second inverter. The second inverter maybe either serially or parallel coupled between the output of the immittance converter and a load.

US Patent:

20170346283, Nov 30, 2017

Filed:

Jan 4, 2017

Appl. No.:

15/398172

Inventors:

- Cambridge MA, US
David J. Perreault - Andover MA, US
Rajeev J. Ram - Arlington MA, US
Daniel DeWitt Strawser - Cambridge MA, US

International Classification:

H02J 1/00
H02J 13/00
H02J 7/00

Abstract:

The systems and methods described herein are directed towards a microgrid having modular power management units to control and regulate power to maintain a stable energy environment and provide peer-to-peer electricity sharing within the microgrid. The microgrid includes a power source to generate power for the microgrid, a source power management unit coupled to the power source to receive the power, one or more load power management units coupled to the source power management unit to receive a portion of the power and a bi-directional communication system to couple the source power management unit to the one or more load power management units to control and allocate the power from the source power management unit to the one or more load power management units.

US Patent:

20170237351, Aug 17, 2017

Filed:

May 3, 2017

Appl. No.:

15/585676

Inventors:

- Cambridge MA, US
David J. Perreault - Andover MA, US
Robert C.N. Pilawa-Podgurski - Cambridge MA, US

International Classification:

H02M 3/158

Abstract:

A converter circuit and related technique for providing high power density power conversion includes a reconfigurable switched capacitor transformation stage coupled to a magnetic converter (or regulation) stage. The circuits and techniques achieve high performance over a wide input voltage range or a wide output voltage range. The converter can be used, for example, to power logic devices in portable battery operated devices.

US Patent:

20160190943, Jun 30, 2016

Filed:

Oct 29, 2014

Appl. No.:

14/911774

Inventors:

- Cambridge MA, US
David J. Perreault - Andover MA, US
Khurram K. Afridi - Boulder CO, US

International Classification:

H02M 3/335

Abstract:

A split drive transformer (SDT) and use of such a transformer in a power converter is described. The power converter includes a power and distributor circuit configured to receive one or more input signals and provides multiple signals to a first side of the SDT. The SDT receives the signals provided to the first side thereof and provides signals at a second side thereof to a power combiner and rectifier circuit which is configured to provide output signals to a load. In some embodiments, the SDT may be provided as a switched-capacitor (SC) SDT. In some embodiments, the power converter may optionally include a level selection circuit (LSC) on one or both of the distributor and combiner sides.