On Identification of Parameters of Mathematical Model of the System for Charging Battery from a Small Wind Power Generator

Savonius wind turbines, like all vertical-axis turbines, do not require a wind orientation system and they start rotating at low wind speeds. These features along with the relative simplicity of manufacturing such wind turbines, allow considering them as a promising design option, including for operation in remote areas. This paper considers a small wind power generator consisting of a Savonius wind turbine, a three-phase permanent magnet electric generator, a rectifier, a battery, and a unit intended to control voltage at the battery input. The charging process is controlled by regulating the voltage supplied to the battery. A closed mathematical model is developed that describes both the mechanical and electrical parts of the system under consideration. The aerodynamic moment acting on the wind turbine blades is described using the quasi-steady approach. A qualitative analysis of the resulting dynamic system is carried out. A laboratory model of the described setup is manufactured. A series of experiments with this model are carried out in the wind tunnel of the Institute of Mechanics of Moscow State University. During these experiments, steady modes of the system were studied at different states of battery charge and different values of the control voltage generated by the control unit. An algorithm to control this voltage is proposed intended to carry out the parameter identification procedure. Based on the obtained data, parameters of the developed mathematical model are identified. It is shown that the parameter values found in the result of this procedure provide a good agreement between the results of numerical simulation and the experimental data.

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