快锻液压机速度位置复合控制特性仿真研究

为提高快锻液压机的控制精度与响应速度,在传统锻压机四通道负载口独立控制与位置闭环控制原理的基础上,提出快锻液压机速度-位置复合控制策略。根据给定的目标位置和运行速度,结合锻压机实际工况,设计出期望的位移曲线,利用速度位置复合控制策略,实现锻压机活动横梁按照所设计的位移曲线运行,并在接近上下顶点时精确定位。分析了锻压机的四象限工作特性,建立了锻压机液压系统理论模型,并在此基础上,搭建了锻压机机液联合仿真模型,仿真研究结果表明:采用速度-位置复合控制系统,使锻压机的活动横梁能够无滞后地按照设计的位移曲线与速度曲线运行并实现了高精度定位,定位精度能够达到0.3mm之内;随着加压工进行程的减少,定位精度逐渐提高。

Simulation on Compound Control Characteristics of Velocity and Position for Quick Forging Hydraulic Press

In order to improve control precision and respond speed of quick forging hydraulic press, a velocity-position compound control strategy is proposed based on independent metering control technology and position closed-loop control theory of quick forging hydraulic press. According to the given target position and operating velocity, an expected position curve is designed combining the actual working condition of forging press. By using the proposed velocity-position compound control strategy, we can operate the moving beam of forging press according to the designed position curve and it can be accurately positioned when the moving beam approaches to its upper and lower limit positions. In the research, the four-quadrant characteristics of forging press are analyzed and a theoretical model of the hydraulic system of forging press is established. On this basis, a mechatronics-hydraulics co-simulation model of forging press is established. The simulation results show that, by using the velocity-position compound control strategy, we can operate the moving beam of forging press according the designed position and velocity curves without delay and it can realize high precision positioning. The positioning accuracy is within 0.3 mm, and the positioning accuracy is gradually improved with the reduction of pressure feed stroke.