Robust speed control of an automotive engine using second order sliding modes

Speed control of an automotive engine based on sliding mode techniques has been presented. A 2-sliding “super twisting” algorithm has been applied since it does not require the time derivative of the sliding variable, which in this case would involve estimating engine acceleration. This and the associated flatness properties enable a sliding mode controller to be constructed which uses only measured engine speed and does not require the use of an observer. The controller tracks not only the set point speed but also shows robustness to the parameter variations and load torque disturbances and is valid across a wide operating envelope. Simulation results using a two subsystem IC engine model have also been presented.