Improved integral separation type PID control method

Abstract

The invention discloses an improved integral separation type PID control method, belonging to the field of the PID control. Because the upper limit value umax and the lower limit value umin of the theoretical output value are set, too large or small control amount can be avoided. Even if the integral saturation phenomenon occurs, the overshoot can exit quickly due to less integral accumulation, and hereby the response speed of the overshoot is increased and the overshoot is reduced. In addition, the increment delta P of the theoretical output value and the difference delta U of the theoretical output value and the set threshold value are calculated, and the increment delta P is compared with the difference delta U: the smaller one of the increment delta P and the difference delta U is compared with xi if the overshoot phenomenon is possible to occur, wherein, the integral coefficient ki is easy to be neglected at the moment and the occurrence of overshoot is prevented hereby, and the smaller one of the increment delta P and the difference delta U is compared with the xi if the static errors of the system are likely difficult to be eliminated, wherein the integral coefficient Ki is easy to be considered at the moment and the static errors of the system are easy to be eliminated hereby. The improved integral separation type PID control method can also realize the positive and negative adjustment, thus the adjustment precision of the system can be improved.

Description

technical field [0001] The invention relates to a PID control method, in particular to an improved integral separation type PID control method. Background technique [0002] The PID control method is the most widely used control law in process control. There are three coefficients in the PID control law: proportional coefficient k p , integral coefficient k i and differential coefficient k d . The proportionality factor k p The function is to speed up the response speed of the system and improve the adjustment accuracy of the system: the proportional coefficient k p If it is too large, it is easy to produce overshoot; the proportional coefficient k p If it is too small, the adjustment accuracy will be reduced, and the response speed will be slowed down, thereby prolonging the adjustment time. The integral coefficient k i The function is to eliminate the static error of the system: the integral coefficient k i If it is too large, integral saturation will occur in the ...

AI Technical Summary

Problems solved by technology

[0004] However, the integral-separation PID control method still has the problems of slow response to exiting overshoot, inability to achieve forward and reverse regulation, and low regulation accuracy.

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