Multivariable torque tracking control for E-IVT hybrid powertrain

This study deals with the control of a hybrid vehicle powertrain, composed of three actuators (one engine, two electric machines). This powertrain belongs to the electric-infinitely variable transmission class. In order to achieve low fuel consumption, drivability and electric power management, controllers must achieve simultaneously three specifications: tracking engine speed, wheel-torque and battery power references. Decoupled controlled-output behaviours and maximal performances are also required. In order to imitate a classical powertrain control structure, the control structure is split into two parts. The interest is to decouple transmission speed ratio control and wheel torque control. A model-based design approach is proposed, that directly deals with robustness and decoupling, in a full multivariable and frequency-dependent framework (H ∞ synthesis). Closed-loop simulations are presented. Stability and performances faced to disturbances and non-linearities are also evaluated, using the theory of linear parameter varying systems.