Study on Vibration Characteristics of Electro-Hydraulic Excitation System Controlled by Alternating Flow Distribution Rotary Valve

Taking advantage of the superiority of valve controlled electro-hydraulic excitation system with wide vibration frequency and adjustable amplitude, a rotary valve controlled electro-hydraulic excitation system is proposed. The structural composition of system and the excitation principle of alternating flow distribution due to rotary valve are formulated. The system mathematical model is derived and a simulation model is constructed based on Matlab/Simulink, and the accuracy of the simulation model is verified by prototype experiments. In accordance with this model, the influence law of main structural parameters of rotary valve and excitation hydraulic cylinder on the vibration characteristics of electro-hydraulic excitation system are indicated. The results reveal that the system vibration waveform obtained from model simulation and prototype experiment are almost identical with only 8.97% error. The effective length of spool groove and the spool radius increased, the system vibration displacement improved. The number of oil grooves increased, the system vibration frequency expanded. With the increase of the spool radius, the vibration displacement of the system increases greatly and the vibration characteristics of the system has affected significantly. The effective working area of hydraulic cylinder piston and equivalent mass increased, the system vibration displacement decreased. The vibration characteristics of the system have remarkable adjustability and prominent working output characteristics.