Control Applied to a Reciprocating Internal Combustion Engine Test Bench under Transient Operation: Impact on Engine Performance and Pollutant Emissions

Ismael Payo,Luis Sánchez,Enrique Caño,Octavio Armas

doi:10.3390/en10111690

Abstract

This work presents a methodology to adjust the electronic control system of a reciprocating internal combustion engine test bench and the effect of the control parameters on emissions produced by the engine under two extreme situations: unadjusted and adjusted, both under transient operation. The aim is to provide a tuning guide to those in charge of this equipment not needed to be experts in control engineering. The proposed methodology covers from experimental plant modelling to control parameters determination and experimental validation. The methodology proposed includes the following steps: (i) Understanding of test bench and mathematical modeling; (ii) Model parameters identification; (iii) Control law proposal and tuning from simulation and (iv) Experimental validation. The work has been completed by presenting a comparative experimental study about the effect of the test bench control parameters on engine performance profiles (engine speed, engine torque and relative fuel air ratio) and on regulated gaseous emissions (nitrogen oxides and hydrocarbons concentrations) and the profile of number of particles emitted. The whole process, including experimental validation, has been carried out in a test bench composed of a turbocharged, with common rail injection system, light duty diesel engine coupled to a Schenck E-90 eddy current dynamometric brake and its related Schenk X-act control electronics. The work demonstrates the great effect of the test bench control tuning under transient operation on performance and emissions produced by the engine independently of the engine accelerator position demanded before and after the test bench tuning.

Highlights

Nowadays, the applications of electronic control to the operating processes of engines and vehicles are varied
In a simple way the engine can be modeled as a linear first order system, non linearity introduced by some elements such as the turbocharger and the electronic control unit (ECU) [17] have to be considered when analyzing simulation results
This work has demonstrated the importance of using a suitable control law and adjusting the controller parameters in a reciprocating internal combustion engine test bench

Summary

Introduction

The applications of electronic control to the operating processes of engines and vehicles are varied. Other works have focused the application of electronic control techniques directly on Diesel engines with the objective of reducing fuel consumption and pollutant emissions by means of a switching strategy between both the high and low pressure exhaust gas recirculation systems [8] or Energies 2017, 10, 1690; doi:10.3390/en10111690 www.mdpi.com/journal/energies. Different EGR and injection strategies have been compared in order to study the effect of biodiesel fuels on performance and emissions of Diesel light-duty engines [12]. No less important have been those works related to the assessment of other types of techniques, as the use of biharmonic maps, to predict performance and emissions of vehicles working in captive fleets. In this work authors indicated the possibility of introducing the use of this technique in ECU operation [13]

Methods

Results

Conclusion