METHOD AND DEVICE FOR THE DIAGNOSIS OF AN NOX SENSOR FOR AN INTERNAL COMBUSTION ENGINE

• Main Authors: WALDE TIM, KILINC MUAMMER, ARLT TINO, BAUMANN THOMAS
• Format: Patent
• Language: English
• Published: 31.03.2011
• Subjects: BLASTING; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TOTRANSPORTATION; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; ENGINE PLANTS IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; 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; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; STEAM ENGINES; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; WEAPONS

IN a method and a device for the diagnosis of an NOx sensor (54) for an internal combustion engine, during a homogenous operation of the internal combustion engine, a base diagnostic value (NOx_DIAG_BAS) of the NOx sensor (54) is determined as a function of a reference value (I_REF) of a measuring signal of the NOx sensor (54) determined in a new state of the NOx sensor (54) and a current value (I_AV) of the measuring signal of the NOx sensor (54). A time-dependent measuring value sequence (O2_EG_T) of the oxygen content of the exhaust gas in the exhaust gas system (14) is determined by the exhaust gas probe (53). Depending on the measuring value sequence (O2_EG_T) of the oxygen content of the exhaust gas, and the base diagnostic value (NOx_DIAG_BAS) of the NOx sensor (54), a corrected diagnostic value (NOx_DIAG_COR) is determined for the NOx sensor (54).