Digital hydraulic variable pitch control of wind turbine generator

When the wind speed is higher than the rated value, the variable pitch control of wind power system, in order to stabilize the output power of the generator. At present, the conventional variable propeller pitch control way mainly for electric pitch and hydraulic variable pitch mode. The system has the advantages of compact structure, synchronization and accuracy, but it is easy to generate excess heat load, which is difficult to realize the variable pitch control of large inertia load. Hydraulic variable propeller pitch is easy to realize high inertia load pitch pitch control, but the valve controlled cylinder and piston rod form transmission mechanism, the transformation of linear displacement of the hydraulic cylinder for pitch angle displacement, due to the linear displacement and angular displacement between the nonlinear conversion, resulting in system control precision is low dynamic performance is poor.

Digital hydraulic motor variable pitch control, the control characteristics of fully digital hydraulic motor (motor angle and control pulse number corresponding, the motor angular speed and control pulse frequency corresponding) as the transmission and control of the core, the whole system constitute with and electric pitch from the same system simple, and a hydraulic variable propeller pitch is easy to achieve high inertia load of the variable pitch control advantages. The digital hydraulic variable pitch control system overcomes the disadvantages of easy to overheat and hydraulic variable pitch structure and low control precision. At the same time, wind power system due to the complexity of the working state, and often due to changes in the work environment and installation position and state mutation. Thus the integration for system modeling and identification techniques and data intelligent optimization control, to set precise control and stable operation has important significance.

Digital hydraulic motor variable pitch control system to promote the development of digital, information technology and intelligent innovation of wind power technology.