负载敏感变速同步驱动原理与特性研究

Load Sensitive Variable Speed Synchronous Drive Principle and Characteristics

液压分流同步驱动以分流元件(如分流阀、分流马达)为控制元件,通过等量分流原理来实现多执行器的同步驱动,具有结构简单、成本低的优点,但在时变负载或大偏载工况下分流元件的分流精度显著降低,难以满足高精度同步需求。据此,提出负载敏感变速同步驱动系统,其由负载敏感变量泵和负载敏感分流阀构成,其中负载敏感分流阀是一种新型的分流阀,其利用负载敏感压力补偿原理可以消除时变负载和偏载对同步精度的影响,并具有调速以及负载敏感的功能。首先,阐述负载敏感分流阀及变速同步驱动系统的结构和工作原理;然后,基于AMESim建立系统仿真模型;最后,在变速、时变负载、大偏载等工况下研究了新型分流阀及其同步系统的同步特性。结果表明:在时变负载和大偏载下,分流阀的分流误差小于1‰,其远远低于现有分流阀的分流误差,并实现了高精度的变速同步驱动,且系统效率较高,可取代一部分价格昂贵、维护困难的闭环同步驱动。为高精度的分流阀及变速同步驱动奠定了理论基础,可丰富液压同步驱动的理论和形式。

The hydraulic flow dividing synchronous drive uses the flow divider(such as flow dividing valve and motor)as the control elements,and realizes the synchronous drive of multiple actuators by the principle of equal amount of flow dividing.It has the advantages of simple structure and low cost,but the flow dividing accuracy of flow divider is significantly reduced under the condition of time-varying load or large bias load,so it is difficult to meet the demand of high-precision synchronization.In view of the above problems,a load sensitive variable speed synchronous drive system is proposed,which is composed of a load sensitive variable pump and a load sensitive flow dividing valve.Load sensitive flow dividing valve is a new type of flow dividing valve,and can eliminate the influence of time-varying load and bias load on the synchronous accuracy by using the load sensitive pressure compensation principle,and has the functions of speed regulation and load sensitivity.First,the structure and working principle of load sensitive diverter valve and variable speed synchronous drive system are described.Then,the simulation model of the system is established based on AMESim platform.Finally,the synchronization characteristics of the new valve and its synchronization system are studied under the conditions of variable speed,time-varying load and large bias load.The results show that the error of the flow dividing valve is less than 1‰under time-varying load and large bias load,which is far lower than that of the existing flow divider,and realizes high-precision variable speed synchronous drive.The system efficiency is high,and can replace some closed-loop synchronous drives which are expensive and difficult to maintain.It lays a theoretical foundation for high-precision diverter valve and variable-speed synchronous drive,and enriches the theory and form of hydraulic synchronous drive.