Multiple sliding surface control of idle engine speed and torque reserve with load torque estimation

A novel controller based on multiple sliding surface control is adopted to automotive engine control at idle condition. The control task is to maintain the engine speed and the torque reserve at their reference values despite parameter uncertainties and variations in the intake-to-torque-production delay. Additionally, a disturbance estimator is applied to reconstruct unknown load torque disturbances based on measurements of the engine speed. A validated nonlinear simulation model is used to evaluate the performance of the closed-loop system and it is shown that the system is robust with respect to the mentioned uncertainties and disturbances.