Simulation of dynamic performance of  the PQ valvecontrolled hydraulic system

ZHANG Xinwei, ZHANG Hong
（School of Mechanical Engineering, Dalian University of Technology, Dalian 116023, China）

Abstract: In order to solve the problems in the control capacity of the hydraulic systems of rubber internal mixers, the proportional pressure/flow hydraulic valve (PQ valve) was investigated. The PQ valve, which is able to adjust both pressure and flow simultaneously, and to a large extent, decides the quality of the rubber products, was considered as an indispensible constituent of the hydraulic control system of modern rubber internal mixers. After the analysis of the structure and the operation principle of the PQ valve, the mathematical model to the dynamic performance of the PQ valvecontrolled hydraulic system was established, the way of drawing the power bond graph and that of carrying out dynamic performance simulation with the aid of Matlab/Simulink were presented, and finally the results of the dynamic simulation was evaluated. The experimental results show the theoretical basis helping to improve the control capacity of the PQ valve.
Key words: PQ valve; power bond graph; equation of state; dynamic performance simulation