Method and device for detecting faults of gas exhaust pipeline of diesel engine

Abstract

the invention discloses a method and a device for detecting faults of a gas exhaust pipeline of a diesel engine. The method and the device are used for detecting whether the gas injection valve is blocked or not in time. A temperature sensor is mounted on the gas exhaust pipeline of the diesel engine and is positioned downstream from a DOC (diesel oxidation catalyst) and upstream from a DPF (diesel particulate filter). The method for detecting the faults includes: judging whether the time for the diesel engine to enter a recycled diesel oil injection stage reaches to preset time or not; if yes, judging whether a temperature value sensed by the temperature sensor exceeds a preset temperature or not; if not, controlling a diesel injector to inject diesel oil in a distance backwards for a certain time, and judging whether the temperature value sensed by the temperature sensor exceeds the preset temperature or not again, and if yes, outputting a first indication signal which indicates thatthe DOC is normal but the diesel oil injection valve is blocked.

Description

technical field [0001] The invention relates to the technical field of fault location, in particular to a fault detection method and device for a diesel engine exhaust pipeline. Background technique [0002] A DPF (Diesel Particulate Filter, particle trap) needs to be installed in the exhaust pipe of the diesel engine to capture unburned carbon particles in the exhaust of the diesel engine. When the carbon particles captured by the DPF reach a certain level, it needs to be regenerated, that is, the carbon particles in the DPF are burned off through high temperature, so that the DPF can regain the ability to capture carbon particles. The source of "high temperature" is often to inject fuel into the exhaust pipe upstream of the DOC (diesel oxidation catalyst, oxidation catalyst) through the fuel injection valve 100. The injected fuel enters the DOC with the exhaust gas, and releases heat after being oxidized by the DOC. Provided to the DPF downstream of the DOC, such as figu...

AI Technical Summary

Problems solved by technology

[0003] However, the working environment of the fuel injection valve 100 in the exhaust pipe is harsh, and it is easy to block, causing the DPF to fail to obtain a high temperature environment. Therefore, it is necessary to detect in time whether the fuel injection valve is blocked on the exhaust pipe of the diesel engine.

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