Rotation Speed and Wind Speed Indirect Measurement Methods for the Control of Windmills with Fixed Blades Turbine

Abstract

The implementation complexity of classical algorithms for wind turbines control limits the utilization of low-end microcontrollers for such applications. We conceived an original method that aims to optimize the efficiency of windmills with fixed blades with the variation ofthe wind speed. In the paper we present an original method to determine generator's efficiency values using measurements that were performed at the prototype's homologation, along with original simplified models of wind turbine and ofwind turbine -generator assembly.Measured values of the frequency, voltage and current of the generator are applied to determine the turbine rotation speed and the wind speed, reducing thus the number of needed sensors. A couple offamilies of regression functions were derived and tuned accordingly to the factory experimental characteristics to allow for afacile calculation ofthe generator's efficiency database table.To further speedup the assessment of the optimum /safety value of the windmill rotation speed, the generator's model is considered to provide the rotation as a function of the wind speed in a tabular format that is further used at run-time as a look-table for rapid interpolations in the control loop. The main advantages of the proposed approach are the simplicity and robustness of the implementation, being easily portable to low-end microcontroller platforms.

Issues regarding mathematical modeling of wind aggregates

“…The models of the considered turbine and the turbinegenerator conversion line of the Cleanfield Energy Corp. fixed blade vertical axis windmill with synchronous generator that we refer to in this paper were presented by [3]. The parameters of the considered wind turbine are the following: ȡ = 1.255 kg/m 3 , S = 7.5 m 2 , H = 3m (the height of the wind turbine tower), R = 1.25 m, a = 0.384, Į = 2, b = 0.24, ȕ = 2.3.…”

Wind speed calculation by using electrical output and wind turbine power curve

“…The wind speed indirect measurement method had previously been investigated as in [4] and [5]. The authors use the output frequency of the generator to calculate the wind speed.…”

Low-cost, rapid prototyping of IMU and pressure monitoring system using an open source hardware design

“…For example, a wearable sensor system [1], speed measurement for Formula One cars [2], and a soil moisture assessment system [3] all have previously reported using accelerometers or IMUs. There also have been a few rapid prototyping systems with various applications, such as that of Budisan et al in 2008, where there was discussion of a low cost solution using low-end microcontrollers as applied to indirect measurement methods for rotation speed and wind speed of windmills [4].…”