AIR-FUEL RATIO CONTROL METHOD OF LEAN-BURN GAS ENGINE FOR GAS ENGINE HEAT PUMP

• Main Authors: NAKAGAWA KENJI, MASUKO TOKUSHIGE
• Format: Patent
• Language: English
• Published: 30.01.1996
• Edition: 6
• Subjects: BLASTING; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TOTRANSPORTATION; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MECHANICAL ENGINEERING; SUPPLYING COMBUSTION ENGINES IN GENERAL, WITH COMBUSTIBLEMIXTURES OR CONSTITUENTS THEREOF; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; WEAPONS

PURPOSE:To control speed by using an engine speed variation in a lean-burn gas engine for a gas engine heat pump having a wide dead zone by performing operation on the engine speed variation by using only engine speed in a section where throttle opening is constant as the object, and performing operation on this engine speed variation, and controlling the air-fuel ratio so that this engine speed variation becomes a target value. CONSTITUTION:An air-fuel ratio control device 10 measures actual engine speed with every single rotation on the basis of a signal from a rotation sensor 9, and calculates an engine speed average value after a certain constant time passes after data is started to be gathered. Next, whether or not there exists data on which a difference between the actual engine speed and an average value is not less than 30 RPM is judged instead of judging whether or not a throttle 6 is moved. When it exists, an engine speed variation in the section is calculated. Next, opening of a bypass valve 8 is changed on the basis of the obtained engine speed variation, and the air-fuel ratio is controlled. In this case, when the engine speed variation is within a range of target engine speed, the NOX concentration is more reduced by putting it on the lean side by control.