A control valve control method, device and intelligent valve positioner

Abstract

The invention provides an adjusting valve control method. The adjusting valve control method comprises the steps of obtaining the displacement between the current position and the initial position of an adjusting valve, wherein the initial position is the position formed when the adjusting valve is switched from the high speed area to the low speed area; determining the ideal speed corresponding to the displacement by referring to a preset standard reference line, wherein the standard reference line is the change line which is generated by the speed of the adjusting valve at the initial position and the difference value of the initial position and the target position and used for representing the decreasing of the speed of the adjusting valve at a uniform speed; comparing the actual movement speed corresponding to the displacement and the ideal speed, and adjusting and controlling the PWM duty ratio of the movement speed of the adjusting valve according to the comparison result so as to enable the actual movement speed to approach the corresponding ideal speed. By means of the adjusting valve control method and device, and an intelligent valve locator, the possibility that as the movement speed is too large, the adjusting valve does not stop timely at the target position is reduced, and then the probability of occurrence of overshoot is reduced.

Description

technical field [0001] The present application relates to the field of regulating valve control, in particular to a regulating valve control method, device and intelligent valve positioner. Background technique [0002] With the rapid development of chemical industry, metallurgy, electric power and pharmaceutical industries, people put forward higher requirements for the control quality of pneumatic control valves in the whole process control. As the core part of the pneumatic control valve, the intelligent valve positioner plays a decisive role in the performance of the entire control valve control system. [0003] At present, the intelligent valve positioner uses the "five-step switch" control algorithm to control the positioning of the regulating valve. Among them, in the "five-step switch" control algorithm, when the regulating valve is in the fast control area, the stick control method is adopted; when the regulating valve is in the low speed control area, the PWM (pul...

AI Technical Summary

Problems solved by technology

[0004] Since the "five-step switch" algorithm uses a fixed or simply changing PWM duty cycle to control the moving speed of the regulating valve in the low-speed control area, when the intelligent valve positioner controls the regulating valve, the regulating valve is approaching At the target position, the PWM duty cycle is still large, resulting in excessive movement speed, so that the regulating valve cannot stop in time at the target position, causing overshoot problems

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