A hybrid actuator modelling and hysteresis effect identification in camless internal combustion engines control

This paper presents a hybrid actuator composed by a piezo and a hydraulic part. Moreover, a cascade PI-PID-PI control structure for camless engine motor applications is considered. The idea of this contribution is using the advantages of both: the high precision of the piezo and the force of the hydraulic part. Piezoelectric actuators (PEAs) are mostly used for precision positioning, despite PEAs' non-linearities, such as saturations, hysteresis and creep. In the control problem these kinds of non-linearities must be taken into consideration. The Preisach dynamic model of the PEA with the above mentioned non-linearities is considered. In particular, the hysteresis effect is considered and a model with a switching function is used also for the controller design. Simulations and measured results are presented.