基于高速开关阀的液压AGC系统的控制算法研究

研究高速开关阀用于液压AGC系统的控制算法,使其代替伺服阀实现液压AGC的数字化控制。基于补偿滞后时间PWM控制与Bang-Bang控制相结合的思想提出三步消零算法,即对于所有的位移调节量,高速开关阀最多只需3次切换,同时消除其零位死区,实现其对位置的快速精确控制。高速开关阀的3次切换体现为6种情况,通过AMESim建立缸体压下仿真模型,并对6种情况的位移响应曲线和速度响应曲线进行仿真分析。理论与仿真分析表明:当初始调节量大于16μm时,运用该算法能够实现液压AGC系统的数字化控制,缸体在上抬和压下时其误差可分别控制在-12~12μm和-4~4μm内。

Control Algorithm Research of Hydraulic AGC System Based on High speed On off Valve

Research the control algorithm that made high-speed on-off valve to replace servo valve in order to realize the digital control of hydraulic automatic gain control ( AGC) system.The three-step elimination zero algorithm was presented, which was based on combining ideas of compensating lag time pulse width modulation ( PWM) control and Bang-Bang control.For all displacement ad-justment amounts, the high-speed on-off valve only was needed to switch three times to eliminate its zero dead zone, and achieved the purpose of controlling position quickly and accurately.The switch for three times of high-speed on-off valve was shown by six kinds of circumstances.The simulation model was created in AMESim software when the cylinder had downward movement.And the response curve of the speed and displacement was analyzed with simulation in six kinds of circumstances.The theoretical and simulation analysis results show that when the initial displacement is more than 16μm, the hydraulic AGC system controlled by this algorithm can realize its digital control.When the cylinder had upward movement and downward movement, the error can be limited within-12~12μm and-4~4μm respectively.