Fuzzy proportion integration differentiation (PID) control method and device for industrial environment high-precision air conditioner

Abstract

The invention discloses a fuzzy proportion integration differentiation (PID) control method and a fuzzy PID control method device for an industrial environment high-precision air conditioner. The method comprises the following steps of: selecting an input quantity of a fuzzy PID controller as a deviation e between an expected value and an actual output and a deviation change rate ec, and establishing a bivariate continuous function relation between parameters Kp, Ki and Kd and the absolute value of the deviation and the absolute value of the deviation change, wherein output quantities are the correction quantities delta Kp, delta Ki and delta Kd of the PID parameters; and determining a fuzzy relation between the three PID parameters and the deviation e and the deviation change rate ec, continuously detecting e and ec in operation, adjusting the three parameters on line according to a fuzzy control theory to obtain adjusted Kp, Ki and Kd, and inputting Kp, Ki and Kd into the PID controller. The control device comprises a fuzzy control circuit on a circuit board, wherein a self-setting mechanism circuit for setting the parameters on line is also arranged on the fuzzy control circuit. The precision of the temperature, humidity and pressure difference control of the industrial environment high-precision air conditioner is improved by introducing the fuzzy control into the conventional PID controller and comprehensively using the characteristics of the conventional PID controller and the fuzzy controller.

Description

technical field [0001] The invention relates to the field of automatic control of air conditioners, in particular to a fuzzy PID control method and device for air conditioners in industrial environments. Background technique [0002] Conventional air conditioning control often uses a PID controller to control the temperature, humidity, and pressure difference of the air conditioner. Proportional-integral-derivative (PID) controller is the most common control regulator in industrial process control. It is controlled by using proportional, integral and differential to calculate the control amount according to the error of the system. The system is controlled by PID It is composed of the device and the controlled object. [0003] Conventional PID control principle such as figure 1 shown. PID controller is a kind of linear controller, which forms a control deviation according to the given value r(t) and the actual output value u(t): e(t)=r(t)-u(t) [0004] The proportional (...

AI Technical Summary

Problems solved by technology

However, the conventional PID controller has great limitations, it is mainly aimed at the field of linear control and the control system that can establish an accurate mathematical model

For example, through the application of high-precision air conditioners in the laboratory, the temperature control range of conventional control is 21.6°C-24.4°C, compared with the laboratory room temperature design of 22°C-24°C, it cannot meet the requirements

[0008] High-precision air conditioners in industrial environments require constant temperature, constant humidity, and strict positive and negative pressures. Among its control objects, temperature and humidity are thermal objects, and mathematical models cannot be established

In addition, due to the non-linearity, hysteresis, parameter time-varying and model uncertainty in the control process, the conventional PID control cannot achieve satisfactory control results in the control of the temperature and room pressure difference of high-precision air conditioners in industrial environments. , so we introduce fuzzy control to achieve

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