DPF temperature control system and control method of low energy consumption tail gas treatment system

Abstract

The invention discloses a DPF temperature control system of a low energy consumption exhaust gas treatment system, comprising a change rate limiter, a feedforward controller, a PID controller, a PWM calculation module and a protection module. The change rate limiter calculates a temperature command value, and the feedforward The controller calculates the feedforward control command according to the exhaust gas temperature Exh_T, the ambient temperature Ambient_T, the fresh air mass flow rate Fresh_MF, the exhaust mass flow rate Exh_MF and the temperature command value, the PID controller calculates the feedback control command, and the PWM calculation module calculates the feedforward control command according to the feedback control command and feedforward The calculated value obtained by adding the control command and the fuel pressure value are calculated to obtain the PWM duty cycle value. The protection module calculates the PWM duty cycle command used to control the fuel solenoid valve according to the PWM duty cycle value and the fresh air mass flow Fresh_MF. The present invention does not rely on engine operating state information and is very suitable for retrofitting of in-use vehicles.

Description

technical field [0001] The invention relates to a DPF temperature control system and a control method, in particular to a DPF temperature control system and a control method of a low energy consumption tail gas treatment system. Background technique [0002] Engine exhaust has been identified as a major contributor to air pollution. In order to remove air pollutants in the exhaust gas, an exhaust gas treatment system is required. Diesel particulate filters (DPFs) are commonly used in exhaust treatment systems to capture particulate matter (PM), which may include unburned hydrocarbon particles or soot and small amounts of other particles such as metal oxide particles or ash. PM particles accumulate in the DPF, increasing the engine back pressure, and before the engine back pressure becomes too high, a regeneration process is required to remove the accumulated soot. [0003] Typically, during regeneration, a heating device is used to raise the temperature of the exhaust gas ...

AI Technical Summary

Problems solved by technology

However, DOC requires a higher PGM (precious metal) load, and only when the exhaust gas temperature is higher than the light-off temperature (usually higher than 200 ° C), the metered injection of fuel can only be started

At the same time, the PGM in DOC is sensitive to the sulfur content in fuel oil, because the high sulfur content in the exhaust gas can poison and make the PGM catalyst ineffective

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