METHOD FOR CORRECTING AN OFFSET OF AN AMMONIA-SENSOR

• Main Authors: CHRISTIAN HEIMANN, FRANK SCHWEIZER
• Format: Patent
• Language: Chinese; English
• Published: 09.10.2018
• Subjects: BLASTING; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TOTRANSPORTATION; 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; 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

The invention relates to a method for correcting an offset of an ammonia-sensor. The ammonia-sensor is arranged at the downstream of at least one SCR (Selective Catalytic Reduction)-catalyst in an SCR-system. The method for correcting an offset of an ammonia-sensor includes the following steps: identifying ammonia slip by means of the ammonia-sensor; setting the modeled ammonia-filling level (FNH3mod) to a maximum ammonia-filling level (FNH3max); performing low metering of a reducing agent on the SCR-system; when the modeled ammonia-filling level (FNH3mod) returns to the nominal ammonia-filling level (FNH3max), ending the low metering; determining the current offset; and correcting the offset by means of the difference which is the difference between the current offset and the predicted offset. 本发明涉及种用于校正氨-传感器的偏移量的方法，所述氨-传感器在SCR-系统中布置在至少个SCR-催化器的下游。所述方法包括以下步骤：首先，借助氨-传感器来识别氨-滑移；然后，将所建模的氨-填充水平（FNH3mod）设定到最大氨-填充水平（FNH3max）；并且随后，为SCR-系统执行还原剂的低计量。当所建模的氨-填充水平（FNH3mod）回到标称氨-填充水平（FNH3max）时，结束低计量。接着，进行当前的偏移量的确定，以及，借助差