串联阀芯阀口独立控制多路阀设计及特性研究

Design and Characteristics of Independent Metering Control Multi-way Valve with Spool in Series

现有多路阀存在大流量低压损控制难、动态特性差等问题,且阀芯机械固联,压损大、自由度低,难以满足高端主机对操纵性、节能性、智能化、负载适应性的需求。为此,基于插装阀大流量控制特性好和滑阀微动性能好的优点,创新提出换向滑阀的进出口串接两个流量放大型比例插装阀的新构型,研制串联阀芯阀口独立控制多路阀。两个插装阀可以根据控制需求设计为流量控制或压力控制功能,系统自由度高,具有很高的智能化潜力。为了实现流量和压力的高精度冗余控制,设计串联式双级位移闭环+并联式流量/压力闭环控制策略,通过仿真研究位置、流量、压力三种工作模式下阀的特性。并试制样阀,搭建试验台对压损特性、位移滞环、流量控制特性、动态响应特性和稳态负载特性进行了测试。结果表明,样阀额定流量达到300 L/min,主阀位移滞环小于1%;主阀阶跃响应小于35 ms,具有较高的动态特性;流量最大偏差小于5%,流量控制精度高。

Existing multi way valves have problems such as difficulty in controlling large flow and low pressure losses,and poor dynamic characteristics.The inlet and outlet of the multi way valve are coupled,resulting in large pressure loss at the valve port and low system freedom.The existing multi way valve is difficult to meet the requirements of high-end hosts for maneuverability,energy conservation,intelligence,and load adaptability.Therefore,based on the advantages of high flow control characteristics of cartridge valves and good slide valve micromotion performance,a new configuration is innovatively proposed.This new configuration is to connect two flow amplification proportional cartridge valves in series at the inlet and outlet of the reversing spool valve,and further develop a series spool valve port independently controlled multi way valve.The two cartridge valves can be designed as flow control or pressure control functions based on control requirements.The valve has a high degree of freedom in the system and has a high potential for intellectualization.In order to achieve high-precision redundant control of flow and pressure,a series two-stage displacement closed-loop+parallel flow/pressure closed-loop control strategy is designed.The characteristics of the valve under three operating modes of position,flow,and pressure were studied through simulation.Further,a sample valve was trial-produced.A test rig was built to test the pressure loss characteristics,displacement hysteresis,flow control characteristics,dynamic response characteristics,and steady-state load characteristics.The results show that the rated flow rate of the sample valve reaches 300 L/min,and the displacement hysteresis of the main valve is<1%;Main valve step response<35 ms,with high dynamic characteristics;Maximum flow deviation<5%,high flow control accuracy.