In this paper a modelling of a hybrid actuator is proposed. The hybrid actuator consists of a piezo, a mechanical and a hydraulic ratio displacement. This paper deals with a hybrid actuator composed by a piezo, and a hydraulic part controlled using a regulator for camless engine motor applications. The discrete control law is derived using the well-known Backward Euler method. An analysis of the Backward and Forward Euler method is also presented. Simulations with real data are shown.