Modeling of a hydraulic wind power transfer system uitilizing a proportional valve

Hydraulic circuits can transfer remarkable amount of energy in the desired direction without taking large space. To implement this technology for harvesting energy of wind appropriately, models of the system are required. Hydraulic wind power technology has benefits of eliminating expensive and bulky variable ratio gearbox and its costly maintenance while enabling the integration of multiple wind turbines. In this paper, the dynamics of different hydraulic elements are studied, nonlinearities are taken into account, pressure dynamics in different parts of the system are studied, and the motor load effects are considered. Ultimately, a non-linear state space representation of the system is introduced. Results of the mathematical model and the Matlab SimHydraulics model are compared to verify of the proposed model. The comparison demonstrates that the mathematical model captures major functions of the hydraulic circuit and can model the system behavior under different operating conditions.