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Wind energy is being used extensively in various areas as an economically and environmentally friendly type of energy. The number of wind farms is continuously developing and it is foreseen a three time increase in contribution of wind energy to European electricity consumption for next twenty years. A complementary trend, of large potential and expectations, is the revival of the small wind turbines (SWT) (<100 kW), suitable for operating in rural areas with moderate winds. In the case of SWT one may use the hydraulic system to convey energy to the ground. When one consumer is used only, the structure of the hydraulic system may be conventional one meaning with impressed flow. For the case of two or more consumers with different loads, the secondary control concept is proposed which means a system with impressed pressure. In this paper, a model for the simulation of the hydraulic system with impressed flow was tested and the step response is presented. The proposed model may be used as an instrument for the design of a hydraulic system with impressed flow.

This paper presents a new type of actuator that uses the properties of a magnetorheological fluid. This actuator allows you to control the speed of a mechanical element and its positioning .The paper shows the conceptual model of the item, the schedule of experiments and their results. There are piston-cylinder type actuators that use magnetic fluid and have internal parts in relative motion. We propose an actuator does not have internal parts in relative motion and neither internal seals. There are shown the results obtained for the mechanical parameters of a new type of actuator with elastic elements, with linear motion. This actuator uses magnetorheological fluid properties. There are presented the constructive elements of the actuator, the properties of the magnetorheological fluid, the calculation procedure of the hydraulic and mechanical parameters and the obtained results. The results confirm the possibility of using it in various technical applications.