Pitch Test System Research And Analysis For Wind Turbine

Pitch system is the key equipment by which wind turbine is quickly connected ingrid,generation works stably and the safety is ensured. Because the randomness anduncertainty of the wind resources, especially with increasing unit capacity of wind turbine,not only engineers debug pitch system parameters directly on the wind turbine is difficultto achieve the desired results, but also the engineers and the turbine have a certain degreeof risk. By building a pitch simulation platform and servo motor which simulating the bladedisturbance torque dragging the motor of pitch system, not only the pitch parameters rangecan be determined, performance test of pitch system can be completed, the costs oftransporting and installing the pitch system is cut in the field test,but also engineers cansave R&D time and the risk that the engineers and the turbine crash can be avoided.The key technology of simulating the blade disturbance torque is the realization ofsimulation algorithmic. Firstly, by analysis and statistic of wind resource data of some windfarm over a year, the simulation of wind speed database for the wind farm is built.Secondly, on the basis of momentum-blade element theory, the profile for modeling ofvariable pitch wind turbine aerodynamic performance is established by using Schmitztheory, which comprehensively considered the effect of blades, blades tip and blades rootloss, hub loss, thickness and width of airfoil, meantime, the wind solidity (the sum of bladewindward area and hub windward area to rotor windward area ratio) during wind turbinestartup and no-load disk effect are also under the consideration. According to the structureparameters of wind turbine, the effect of yaw error and wind shear are also took intoaccount by coordinate transformation. Bases on the phenomenon that different position ofblade element produces different torque and numerical size; the distribution blade elementway of application experience weight is applied to the calculation of wind turbine torque,which solved the problem of wind turbine output accuracy under the limited number ofblade elements and completed the output of real-time power simulation parametersThirdly, after the accuracy of wind turbine model is validated, the model of bladedisturbed torque is established. On the basis of the analysis of the blade disturbance torquewhich consist of centrifugal moment, aerodynamic moment, resetting moment, inertia andresistance moment caused by the air acceleration, friction moment and gravity moment, their math models is established to compute the blade disturbance torque. The model ofpitch system is established for the system simulation, while operating environment of windturbine is complex and system parameters are easily effected, the fuzzy adaptive PIDcontrol system is introduced into position loop of three loops PID controller, whosesimulation results show that the pitch system robustness improve significantly. The systemnumerical model is simulated by matlab with variable pitch wind turbine parameters.Finally, pitch simulation platform whose numerical algorithms load into the PLCcontroller is set up to test the servo motor which simulates the blade disturbance torque...