Design And Research Of Rotary Water Hydraulic Servo Valve

Water hydraulic transmission technology has many advantages, such as environmental protection, safety, efficient, etc.It is much better than oil hydraulic transmission technology in many cases. With the continuous progress of science and technology, water hydraulic transmission technology has been paid more and more people’s attention.And water hydraulic transmission technology has a very broad application prospects in engineering machinery,underwater operation, manufacturing of food and drug and so on. Before the promotion of water hydraulic transmission technology, we should have developed High-performance water hydraulic components first.The precision requirement of water hydraulic transmission system is increasing too.Developing hydraulic servo control system is one of the important parts of hydraulic technology research and development.It is also in the field of academic frontiers of water hydraulic transmission technology and control technology. Servo valve, which is the core of the electro-hydraulic servo control system,should be developed and improved. In this paper, designed and developed a rotary hydraulic servo valve.The movement form of this servo valve spool is rotary, instead of straight acting movement form.Simulation experiment is done using Matlab/Simulink module to get the dynamic characteristis.The main works is as follows:1) According to the working principle of the servo valve and the structure of the existing design, designed and developed a rotary hydraulic servo valve. The DC torque motor is connected with the valve spool directly.The rotation angle and the amount of valve opening of the orifice are proportional. The preliminary design of the working principle and structure of rotary water hydraulic servo valve have been done. Discussed and calculated the stiffness of rotary servo valve and cavitation index which is used to determined the anti-cavitation performance. Ultimately determine the valve port is in the form of two stage throttle orifice valve port.2) According to the results of the valve orifice port, improved the design scheme of the servo valve.Using Pro-E 3D modeling for further structure design and improvement. By using two-stage throttle valve port instead of one stage throttle valve port.And valve sleeve have been designed as one part,instead of two parts.Redesigned the valve port distribution.The rotary working principle and structure of servo valve is adjusted. The selection of materials and standard parts is done. As well as the selection of servo motor, suitable encoding board.3) Calculated mathematical modeling of the servo valve. According to the voltage of DC torque motor equation, torque equation and torque of the motor output equation, calculated the transfer function. Using Pro-E software for analysis to valve spool and other parts of the servo valve, calculated all the parameters of transfer function.Using Matlab/Simulink simulation module, simulated the frequency response simulation. The response frequency, phase bandwidth of the servo valve. Compared with the existed servo valve performance parameters, to determine the rationality of plan.The frequency response of the rotary hydraulic servo valve in this paper is the dynamic performance parameters. Compared with the existed servo valve dynamic parameters, the results basically reached the servo valve design requirements.It can provide a theoretical basis for the future work of the prototype test and other follow-up works.