| 摘要 |
PURPOSE:To detect abnormality in a water injection system in a very short time by means of detection of the rate of change of exhaust temperature by detecting and recognizing abnormality in the water injection system, and detecting actual NOx and O2 at the same time, and comparing the actual NOx with limit NOx via a comparator. CONSTITUTION:A water injection control unit includes a device for detecting abnormality in a water injection valve using a proximity switch, and devices 6, 1, 2 for detecting the abnormality as excess in the rate of change of exhaust temperature when loads are leveled, or as temperature deviation. The control unit also includes a device which stops water after detection, performs diagnosis of the exhaust temperature again during fueloil operation and recognizes any abnormality in a water injection system. The control unit further includes a device which detects actual NOx and O2, compares limit NOx with the actual NOx by means of a comparator 10, and continues the fuel operation of the abnormal cylinder if the actual NOx is not full, and a device 11 for lowering intake temperature. Even if a plurality of cylinders become abnormal, operation at less than the limit NOx is made possible. Abnormality in a water injector is therefore clearly detected at early stages as necessary and lowering of one operating ratio of the water injector can be prevented. |
