Measurement And Controlling System Research Of Wind Turbine Pitch Bearing Test-bed

Wind turbine pitch bearing is arranged in the root of three wind turbine blades, with motor, reducer and gearing make up variable pitch system, used to adjust the frontal area of wind turbine blade to maintain power stabilization of wind power generator. Variable pitch bearings is not only bear the axial load and radial load, but also bear enormous overturning moment, so it sometimes can't swing in its duration of work. In the past wind turbine failure statistics, the damage proportion of wind turbine pitch bearings is high, so it must be make simulation tests for its performance before running in order to preventing any defective bearings are installed into the wind turbine.According to the performance test requirements of variable pitch bearings, this paper proposes a new testing theory of test machine, and researches the project of test machine's intelligent measurement and control system. This measurement and controlling system uses IPC as the hardware platform, with data acquisition and control card, sensors, proportional pressure-reducing valve, frequency converter and other implementing components constitute closed-loop control system of variable frequency speed-regulating and hydraulic loading. It uses four hydraulic loading devices to achieve dynamic simulation of axial load, radial load and overturning moment of variable pitch bearings. Based on the balance torque measuring principle, it uses dynamic torque sensor to measure the friction torque of variable pitch bearings under different loads. The software system of measurement and control system is based on Visual C++ 6.0. It can load precise press to the measured bearing according to the load spectrum of actual working conditions, and control automatic movement, collect, analyze and process experimental data automatically, achieve capability examination of friction torque of wind turbine pitch bearing.From the three main parts of the testing principle, hardware structure and software design, this paper introduces the development process of the measurement and control system detailedly. In the end, through simulation experiments, show that this measurement and control system can complete load test of variable pitch bearings, collect, process, display experimental data automatically, provide data support for performance testing of variable pitch bearings.