Pragmatic Method to Obtain Optimal Control Laws for Small Windgenerators

The chapter presents a pragmatic method to obtain optimal implementable control methods of variable speed fixed blades small windgenerators, depending of available information values about the control object (wind speed, rotation speed, air density, blade’s position in the air flow). The elaborated method presumes the existence off a laboratory model having: an electromechanical analog model of considered turbine in accordance with a pre-established turbine theoretical mathematical model and the full generator-grid system, identical with the implemented on the site one. The pre-established turbine theoretical model allows to calculate for different wind speed values, in the established working domain, the optimum turbine values

n

T opt k

,

M

T opt k

,

P

T opt k

, k=

1, 2, ... .Having the obtained optimum turbine operation values, these optimum regimes may be experimentally obtained on the laboratory model, and all operation values of different elements of the conversion line “generator - power electronic interface – grid” may be measured. Different obtained parameter pairs may be use to determine regression functions that may be used as optimum wind control laws. Considering the hardware structure of studied windgenerator were chosen some optimum control laws. The obtained control laws was implemented and verified on Matlab / Simulink model considering different wind speed variations. The simulation results confirm the opportunity and the quality of the adopted optimal control law.