Hoi M Wong

US Patent:

6474323, Nov 5, 2002

Filed:

Aug 8, 2001

Appl. No.:

09/924969

Inventors:

Niel Lenannes Beck - Bonira CA
Kresimir Gebert - San Diego CA
Hoi Ching Wong - Carlsbad CA

Assignee:

Servoject Products International - San Diego CA

International Classification:

F02B 2904

US Classification:

123679, 60599, 123689

Abstract:

The performance of a compression ignition internal combustion engine is improved by optimizing excess air ratio (lambda) and/or intake air charge temperature (ACT) on a full time, fall range basis. The basic procedure is to first determine the desired or optimum lambda and then to control ACT and intake manifold absolute pressure (MAP) to maintain them at the optimum values for the fuel quantity required at a particular operating point. This approach allows control of both temperature and pressure of the air entering the engine. Full range control requires that lambda and ACT be controlled both upward and downward to achieve optimal engine performance. Control of both lambda and ACT is further enhanced through the use of a supercharger with adjustable input power installed in series with a standard turbocharger compressor of the engine. Supercharger control may if desired be supplemented with turbo air bypass (TAB) control, turbocharger variable area nozzle or wastegate, turboexpander control, and intake and exhaust valve control including skip fire of both fuel and air. The essence of optimized lambda control is to measure the physical properties of the working fluid in the intake manifold, exhaust manifold, or both, compute the actual value of lambda, and compare that actual value with an optimum value for the prevailing engine operating conditions.

US Patent:

6742335, Jun 1, 2004

Filed:

Jul 11, 2002

Appl. No.:

10/193257

Inventors:

N. John Beck - Bonita CA
Hoi Ching Wong - San Diego CA
Kresimir Gebert - Villa Park IL

Assignee:

Clean Air Power, Inc. - San Diego CA

International Classification:

F02B 3344

US Classification:

606052, 12356817, 12356811, 23926511, 60295, 60278, 60298, 60291

Abstract:

EGR mass fraction or a value indicative thereof can be calculated based on temperature measurements rather than mass flow and/or pressure measurements, hence negating the need for expensive and relatively unreliable measurement devices in an active EGR system for an internal combustion engine. The EGR system may be a low pressure EGR system configured to direct cooled, filtered EGR to the engines air intake system using an effective, simple venturi and/or a continuously regenerated catalytic particulate trap. The resultant system can reduce NOx emissions in a diesel engine on the order of 50% and approximately 90% for CO, HC, and PM. NOx and other emissions can be reduced still further when the EGR system is combined with other pretreatment and/or after treatment devices. Many components of the low pressure EGR system are also usable in a passive EGR system.

US Patent:

6948475, Sep 27, 2005

Filed:

Nov 12, 2002

Appl. No.:

10/292115

Inventors:

Hoi Ching Wong - San Diego CA, US
John Payne - Vancouver WA, US
Niels Johannes Beck - Bonita CA, US

Assignee:

Clean Air Power, Inc. - San Diego CA

International Classification:

F02M051/00
F02P005/00

US Classification:

123299, 123304, 12356812, 12340619, 123478

Abstract:

An EGR equipped internal combustion engine is controlled to maximize the beneficial effects and minimize the detrimental effects of EGR on engine operation. Specifically, at least one parameter indicative of the Oconcentration in the intake mixture and/or at least one parameter indicative of the HO concentration in the intake mixture is monitored, and the monitored parameter is relied on to control one or more aspects of engine operation by open loop adjustment of other control strategies and/or by a separate closed loop control strategy. These controls are applicable to virtually any engine, and are particularly beneficial to lean burn engines such as diesel (compression ignition) engines, spark ignited natural gas engines, and dual fuel or other compression ignited natural gas engines. The engine may be equipped with either actively controllable EGR or passive and uncontrolled EGR.

US Patent:

7270089, Sep 18, 2007

Filed:

Jun 10, 2004

Appl. No.:

10/552894

Inventors:

Hoi Ching Wong - San Diego CA, US

Assignee:

Clean Air Power, Inc. - San Diego CA

International Classification:

F02D 19/00
F02B 7/00
F02M 21/00

US Classification:

123 27GE, 123526, 123431

Abstract:

At least one engine operating parameter other than total fuel energy content is taken into account when transitioning between operating modes in a dual fuel or other multimode engine () in order to maintain a smooth transition between modes. The parameter preferably comprises at least one of primary fuel excess air ratio (lambda) and ignition timing and preferably is controlled in addition to total fuel energy content control. Lambda control is especially beneficial because it permits the control system to compensate for the engine's inability to substantially alter the instantaneous air mass in the combustion chamber during the transition period. For instance, during a transition from pilot ignited gaseous fuel mode to diesel mode, the controlled parameter preferably comprises diesel lambda, and the controlling step comprises setting diesel lambda at a relatively high value at the beginning of the transition period and thereafter reducing diesel lambda during the transition period.

US Patent:

8527186, Sep 3, 2013

Filed:

Sep 8, 2010

Appl. No.:

12/877487

Inventors:

Hoi Ching Wong - San Diego CA, US
Madhusudhan Chellappa - San Diego CA, US
Carlos Gamez - Ocala FL, US

Assignee:

Clean Air Power, Inc. - Poway CA

International Classification:

F02D 41/14
G06F 19/00

US Classification:

701109, 123674, 123695, 701103, 701106

Abstract:

A computer-implemented method is used to correct deviations between a predicted gas excess air ratio and a calculated excess air ratio in a dual fuel engine or other gas fueled compression ignition engine. The method includes determining gas excess air ratio for the engine based at least in part on at least one detected current operating parameter and calculating a predicted exhaust gas oxygen concentration engine based on the predicted gas excess air ratio. A time based filtered predicted exhaust gas oxygen concentration value may then be calculated and compared to a time-based filtered measured exhaust gas oxygen concentration value. The resultant oxygen concentration deviation value may be used to generate a corrected predicted gas excess air ratio.

US Patent:

20110213545, Sep 1, 2011

Filed:

Feb 25, 2011

Appl. No.:

13/034946

Inventors:

Robert Oaten - Lancashire, GB
Hoi Ching Wong - San Diego CA, US

Assignee:

Clean Air Power, Inc. - Poway CA

International Classification:

F02D 41/30
F02D 45/00

US Classification:

701103, 701102

Abstract:

The timing of a controlled event is advanced or retarded in an IC engine by emulating the engine speed and position signal pattern prior to transmission of that signal pattern to an output such as a fuel injector. In a multi-controller engine in which a second controller is controlled at least in part by signals delivered by first controller, the signal preferably is emulated in the first controller prior to transmission to the second engine controller in order to allow the shifting of a timing of a controlled event without direct data transfer from the second controller to the first controller. The technique is particularly well-suited for controlling diesel fuel injection in a dual fuel or other multi-fuel engine. In this case, the first controller must be a dual fuel controller and the second controller may be a diesel controller.

US Patent:

20140076291, Mar 20, 2014

Filed:

Jul 30, 2012

Appl. No.:

14/115472

Inventors:

Hoi Ching Wong - San Diego CA, US

Assignee:

Clean Air Power, Inc - Poway CA

International Classification:

F02M 25/07

US Classification:

12356811

Abstract:

A method of fueling an internal combustion engine including operating the internal combustion engine in a dual-fuel mode in which the engine is fueled by a pre-mixed charge of fresh air, recirculated exhaust gases, gaseous fuel as primary fuel and early injected liquid fuel as a secondary fuel, ignited by a late injected pilot fuel to provide low temperature combustion. The method further includes adjusting EGR and/or fresh airflow to the engine to maintain peak in-cylinder temperature in a desired range, preferably between 1500 K and 2000 K. EGR preferably is controlled to obtain a desired in-cylinder Omole fraction, and fresh airflow preferably is controlled to obtain a desired fresh air lambda.

US Patent:

62730762, Aug 14, 2001

Filed:

Dec 16, 1997

Appl. No.:

8/991413

Inventors:

Niel Lenannes Beck - Bonita CA
Kresimir Gebert - San Diego CA
Hoi Ching Wong - Carlsbad CA

Assignee:

Servojet Products International - San Diego CA

International Classification:

E02D 4104

US Classification:

123679

Abstract:

The performance of a compression ignition internal combustion engine is improved by optimizing excess air ratio (lambda) and/or intake air charge temperature (ACT) on a full time, full range basis. The basic procedure is to first determine the desired or optimum lambda and then to control ACT and intake manifold absolute pressure (MAP) to maintain them at the optimum values for the fuel quantity required at a particular operating point. This approach allows control of both temperature and pressure of the air entering the engine. Full range control requires that lambda and ACT be controlled both upward and downward to achieve optimal engine performance. Control of both lambda and ACT is further enhanced through the use of a supercharger with adjustable input power installed in series with a standard turbocharger compressor of the engine. Supercharger control may if desired be supplemented with turbo air bypass (TAB) control, turbocharger variable area nozzle or wastegate, turboexpander control, and intake and exhaust valve control including skip fire of both fuel and air. The essence of optimized lambda control is to measure the physical properties of the working fluid in the intake manifold, exhaust manifold, or both, compute the actual value of lambda, and compare that actual value with an optimum value for the prevailing engine operating conditions.