Design of an Engine Load Simulator

Abstract

This paper discusses the design details of an engine load simulator. A proportional valve is used to regulate a resistant to the flow from a hydraulic pump. Due to the fact that pressure drop across an orifice is proportional to the square of the flow which is similar to an aerodynamic drag that is proportional to the velocity square. While this is true, more sophisticated control methods can be incorporated. However, the dynamic characteristics of the valve can not be included in designing a controller with an adaptive control method. As will be discussed, the valve effect can be eliminated mechanically or electronically. With the dynamic pressure compensation from the main valve to the pilot valve, the inertia effect of the spool can be reduced. On the other hand, the pressure in the pressure line can be read and compensated for the signal to the pilot valve directly. In addition, a variable structure control for a load simulator will be presented.