Adaptive Engine Torque Compensation with Driveline Model

Jinrak Park,Seibum B Choi ,Joa Sub Oh

doi:10.1051/matecconf/201816604004

Abstract

Engine net torque is the total torque generated by the engine side, and includes the fuel combustion torque, the friction torque, and additionally the starter motor torque in case of hybrid vehicles. The engine net torque is utilized to control powertrain items such as the engine itself, the transmission clutch, also the engine clutch, and it must be accurate for the precise powertrain control. However, this net torque can vary with the engine operating conditions like the engine wear, the changes of the atmospheric pressure and the friction torque. Thus, this paper proposes the adaptive engine net torque compensator using driveline model which can cope with the net torque change according to engine operating conditions. The adaptive compensator was applied on the parallel hybrid vehicle and investigated via MATLAB Simcape Driveline simulation.

Highlights

This paper proposed the adaptive engine net torque compensator according to the multiplied uncertainty on the net torque
This is to compensate the net torque error which is caused by the slow variation of the engine model
The adaptive law of the torque constant for the engine net torque compensator was designed based on the variation of the engine net torque

Summary

Introduction

Eco-friendly automobile technology is attracting attention. So, the automotive precision control technology is developing with electronic control system to satisfy the fuel economy and the performance of a vehicle. In commercial vehicles, it is difficult to know the exact load torque because the air drag force, the rolling resistance and the gradient resistance cannot be exactly estimated. Another solution is needed to compensate the engine net torque instead of the method using the load torque. B. Choi suggested the adaptive estimator to estimate the quantity of the engine net torque compensation and the output shaft torque simultaneously using only the driveline model [2]. The compensator in this paper estimates only one unknown state, the multiplication factor on the engine net torque, using one error variable.

Detail algorithm of adaptive engine net torque compensator

Simulation result

Conclusions