Agricultural tractors make massive use of hydraulic control technology. Being fuel consumption a big concern for agricultural applications, tractors typically use the latest state-of-the-art technology to allow efficient fluid power actuation. Nevertheless, the quantification of the energy loss within the hydraulic system of such applications represents an important step to drive the development of the current technology with cost-effective solutions.
In this paper, the load sensing (LS) circuit that typically equips of the hydraulic remotes is taken as reference. A simulation model has been developed within the Amesim software with the aim of accurately predict the operation of the system including the energy flow from the hydraulic supply to the hydraulic user. The paper particularly details the models of the LS pump and the hydraulic remote valves. Within the research, experimental tests on a reference tractor were designed and executed to allow the model validation. The comparison between the experimental results and the simulation data shows the validity of the model. Furthermore, the model allows highlighting the energy losses in the different components of the system as well as identifying the most favorable operating conditions of the system with respect to energy efficiency. The model can be used in support of future research aimed at formulating a more efficient solution for the hydraulic circuit of agricultural tractors.