现场总线控制系统时延特性及控制

分析了现场总线控制系统前向通道和反馈通道的传输时延特性，针对执行器的工作方式推导了线性被控对象在时间驱动方式下和在事件驱动方式下的离散时间模型，提出了2种现场总线控制系统的控制方法，1种是将随机时延转化为固定时延，进而对固定时延进行补偿；另1种是直接处理随机时延，这2种方法互为补偿，可有效地消除时延对现场总线控制系统性能的不良影响。

Characteristic and Control of Time Delay in Field Bus Control System

The characteristic of the transmitting delay of forward and feedback channels were analyzed. According to the working modes of actuators, a linear control object is converted into time-driven and event-driven discrete time models. Two control methods for field bus control system were proposed. The first method transforms random delay into constant delay that is then compensated; the sencond method processes random delay directly. These two methods compensate each other and can eliminate the deterioration of delay to the control system performances of field buses.