先导式电液配流系统的动态特性

为了实现往复式压缩机排气量的无级调节,满足气量调节对配流过程响应快速性和平稳性的要求,提出一种基于双阀结构的先导式电液配流系统.建立压缩机吸气和回流过程中的配流气阀动力学模型,通过联合仿真研究主要设计参数对电液配流系统动态特性的影响.研究结果表明：电液执行机构的压力飞升和卸压速率是影响气阀动作快慢的关键因素；所设计的配流系统中气阀开启和关闭滞后时间均小于10 ms,气阀响应速度显著提高；供油压力10 MPa、阀片行程2 mm条件下阀片与阀座和行程限制器的撞击速度分别为0.214和1.35 m/s,充分满足可靠性许用要求；气阀动作试验曲线与仿真结果拟合程度高,所述联合仿真模型可以作为电液配流系统性能分析的研究平台.

Dynamic characteristics of pilot-operated electro-hydraulic flow distribution system

A novel pilot-operated electro-hydraulic flow distribution system based on a double-valve structure was proposed for the stepless capacity control of reciprocating compressors, satisfying the requirements of response speed and stability for flow distribution in capacity control. A dynamic mathematical model of distributing valve for the compressor suction and backflow process was established. The influence of main design parameters on the dynamic characteristics of flow distribution system was investigated by co-simulation. The results indicate that the rates of actuator pressure rise and discharge are most important for the response speed of distributing valve. Under normal conditions of proposed electro-hydraulic flow distribution system, the response speed of suction valve increases significantly with opening time and closing time that are both less than 10 ms. The impact velocities of distributing valve plate between valve seat and valve guard are 0.214 and 1.35 m/s respectively with 10 MPa oil pressure and 2 mm valve stroke, which can fully meet the requirements for reliable operation. The motion curves of suction valve accord well with the simulation, suggesting that the co-simulation model is quite suitable for the performance analysis of electro-hydraulic flow distribution system.