Bifurcation of operation modes of small wind power stations and optimization of their characteristics

Abstract

Wind stations of small power (small WPS) are intended to ensure the operation of a small number of electric devices. Under these conditions, the connection of even a single additional consumer may result in operation disturbances. In [1,2], a mathematical model of a small WPS operation was proposed, which allowed a qualitative explanation of the energy output hysteresis phenomenon experimentally observed under variation in the external load. In the present paper, on the basis of this model, we study the problems of existence and stability of steady-state modes and describe their attraction domains. We show that there exist different types of bifurcations of these modes, which result, in particular, in the onset of finite-amplitude periodic motions. For the first time, the performance of a power plant is estimated by the maximal consumption power criterion. The results are compared with the results obtained by other criteria.

Darrieus-Magnus Type Wind Turbine: Dynamics and Control

“…To determine the lateral force and the drag force acting on the Darrieus rotor, we use a quasi-static model (similar to [22][23][24][25][26][27]). We consider a separate Darrieus rotor rotating around its central axis C. Let the rotor be located in a uniform air flow, the velocity U of which is orthogonal to the rotor's axis of rotation.…”

“…We neglect the difference between the air velocities of the blade's points, assuming that the distance OC significantly exceeds the length of the Darrieus rotor blade and length r of the holders and in turn r is significantly larger than the chord of the profile. Such assumptions are quite standard when applying a quasi-static model, for example [22][23][24][25].…”

“…The expression for it is similar to the one in the works [12,13,15]: Here, is the coefficient of electromechanical interaction (constant determined by the properties of the generator) and is the internal resistance of the generator (constant). The expression for the electromechanical torque is based on the publications [23,25], in which a mathematical model is proposed and analyzed, including the equation for changing the current in the local generator circuit.…”

Counter-Rotating Savonius Wind Turbine

“…The interaction between the rotor and the stator of the generator is described by the electromechanical torque T e (from the model [11]): In relation (4), C is the constant coefficient of electromechanical interaction, and σ is the internal resistance of the generator.…”