The Proportion Of Wind Machine Digital Electro-hydraulic Brake Control System

With the wind power industry development, wind turbine have become increasingly demanding the safety and reliability. Among of them, wind turbine's braking performance as one of its main properties, gets more and more attention. The existing wind braking device's brake is installed in the high-speed shaft, thus braking torque is not adjustable, and the main defects are:the braking safety performance is poor; braking process does not run smoothly, which causes big impact, brake linings wear faster; and gear box easy to overload and shatter.Based on the above issues, this paper put forwards the brake control system program that brakes are installed in the gear case's high and low-speed axes, and the high, low-speed shaft braking force are adjusted in real-time by take use of digital electro-hydraulic proportional control technology, and then conducts the simulation analysis and experimental verification.Firstly, according to the principle of wind braking device this paper analyzes the performance of three different braking projects, and proposes brake control system scheme which the brakes are installed in the high and low speed shaft, and high-speed switching valve is considered as the control of the core for the program.Secondly, it analyzes high-speed switch valve dynamic and static characteristics, and their influence on system by taking use of the existing correlative theories, and establishes valve-control cylinder model, analyzing the static and dynamic characteristics, optimizing interrelated parameters; The simulation model of wind speed, braking rotor, transmission links friction torque etc. have been built. Combined with valve-control cylinder model, it also builds the simulation model of the wind turbine brake system. Under different wind conditions, it simulates the entire wind turbine brake system, and the simulation results show that the braking system can meet operational requirements.Finally, it builds the braking system test bed, and determines the carrier frequency of high-speed switching valve experiment, the effective duty cycle of the scope of work, and then take a pressure response test for the export of high-speed switching valve and brake system. The experimental results showed that the braking system program can follow the curve of the objective pressure, verifying the brake system rationality of this paper.Through this research project, a wind turbine realizes high, low-speed shaft braking force digital electro-hydraulic in real-time regulation, which provides new ideas for wind turbine brake system, and provide reference for future wind turbine braking technology research.