智能烘箱温度控制器设计-英文翻译(4)

engineering setting method, it mainly depends on engineering experience, directly in the test of the control system, and the method is simple, easy to grasp, is widely used in engineering practice. Engineering setting method of PID controller parameters, mainly has the critical ratio method, reaction curve method and decay method. Three methods have their characteristics, their common ground is through test, and then according to the engineering experience formula for setting controller parameters. But no matter which kind of method of controller parameter, the need for final adjustment and improvement in the actual operation. Now commonly used is the critical ratio method. Using the method of PID controller parameter setting procedure is as follows: (1) to first select a short enough sampling period make the system work; (2) only in proportional control link, until the system step response of input appears critical oscillation, jot down at this time the proportion of the amplification coefficient and the critical oscillation period; (3) under a certain degree of control is obtained by the formula to calculate the parameters of PID controller.

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