Composite Control of DOC-out Temperature for DPF regeneration

Control of Diesel Oxidation Catalyst (DOC) outlet temperature is critical for the downstream Diesel Particulate Filter (DPF) regeneration. However, the disturbances, delay time variation and model uncertainties make it difficult to control DOC outlet temperature. A Composite Controller (CC) based on modified Active Disturbance Rejection Control (mADRC) with delay-time adaptation was proposed for DOC-out temperature control in this paper. The proposed controller includes a model-based Feedforward controller(FF) and a mADRC. The model based FF was designed based on the model between the reference temperature, inlet temperature, mass flow rate and the fuel injection. The mADRC was modified from regular Active Disturbance Rejection Contoller (rADRC) with an adaptation of input delay time. The input delay time is adapted according to the mass flow rate of exhaust gas. Simulation and test results through high-fidelity GT-Power model show that the proposed design can effectively control the DOC-out temperature.