Research On Adblue Injection Control Strategy Based On LADRC Technology

The diesel engine need to install SCR system to solve the problem of high NO_X emission.The control quality of SCR system adblue injection control strategy directly affects the NO_X purification effect.Now the main stream SCR adblue injection control strategy can be divided into open-loop control strategy based on MAPs,open-loop control strategy based on model and closed-loop control strategy.The open-loop control strategy needs a lot of calibration work,and it has control precision problem.The mainstream closed loop control strategy is just closed loop modification based on the open loop strategy Although the closed-loop control strategy can improve control precision,but it cannot reduce calibration work.LADRC control technology has higher accuracy,simpler arithmetic and less calibration parameters.This paper researched the adblue injection closed loop control strategy based LADRC for SCR system.The research mainly include four parts:?1?Mathematical model of LADRC controlled object.Simplified the SCR model.Simplified the three-dimensional model into one-dimensional model and chose proper SCR chemical reaction kinetic model.Solved the SCR reaction rate with MATLAB/Simulink and then solved NO_X and NH₃ concentrations in catalyst unit.Calibrated the simulation model parameters using experiment data.?2?Researched the LADRC adblue injection control strategy and built the simulation model.The LADRC is the liner simplification of ADRC.LADRC has less calibration parameters and it inherits the advantages of ADRC.Researched the adbule inject control strategy based on LADRC technology.Built the simulation model with MATLAB/Simulink.And Coupled the LADRC simulation model with Urea-SCR simulation model.?3?Analyzed the LADRC adblue injection control strategy based on Simulation model.With the LADRC adblue injection control strategy simulation model,optimized the LADRC control parameters.Simulated the control strategy robustness and applicability for test cycle.The simulation results showed that the LADRC adblue injection control strategy is robust under a variety of disturbances,also the control strategy performs well under ESC and ETC cycle.?4?Tested the LADRC adblue injection control strategy on test bench.Programmed the LADRC adblue injection control strategy and validated the strategy on the test bench.The bench experiment result showed that the control strategy can fulfill the requirement of the national IV and V emission standards.Also the experiment result showed that control strategy has good control precision and dynamic response ability.