Finally, dissipation due to the presence of a pump margin, which obliges the system to operate at a higher
pressure than that requested by the actuator, can be reduced by direct control on pump displacement. This algorithm is based on the integration of both flow rate control and pressure control. Generally, a flow rate control determines pump displacement, hence the displacement is regulated only on the basis of the sum of the flow requests. When the pressure supply value is higher than a limit value (default is 18MPa), the algorithm will control the pump in an electronic load sensing mode, in order to limit the supply pressure value (anti-saturation control). This algorithm is also able to implement anti-cavitation control when the pressure is lower than 0.05MPa. Moreover, in the virtual model of the independent metering distributor position transducers are introduced to realize a position control, one for each valve. In this way it’s possible to carry out a closed loop control, that is more precise than an open loop control and brings the same energy dissipation.