Furnace pressure control method for four-stage alloying furnace based on lpv system model

Abstract

The invention discloses a control method for four-segment alloying furnace pressure based on an LPV system model. The method includes the steps that firstly, a cooling fan is arranged behind a furnace to blow air into a furnace, a linear parameter changing system model of a four-segment alloying furnace is built according to the relation of the furnace pressure of the alloying furnace and the rotating speed of the cooling fan, and a controller state-space equation of the LPV system is obtained and converted into an affine PID controller. Through the robust PID controller design, the convexification processing of performance indexes and solving, a offline simulation result meeting the requirement is obtained, then the result is applied in the practical production process, corresponding controller parameters are adjusted according to practical conditions on a field, and therefore the system can meet the requirement for stability, fastness and accuracy. The furnace pressure can be well controlled, the temperature in the furnace can be effectively controlled, the automatic closed-loop control function is achieved, quick responses can be achieved according to the set furnace pressure, errors are small, and the system stability is high.

Description

technical field [0001] The invention belongs to the technical field of furnace pressure control in the production process of cold rolling and galvanizing, and in particular relates to a furnace pressure control method of a four-stage alloying furnace based on an LPV system model. Background technique [0002] In the production of hot-dip galvanized alloying, the furnace temperature of the four-stage alloying furnace has a direct impact on the quality of the alloyed steel plate. However, the temperature of the alloying furnace is affected by the pressure in the alloying furnace. When the pressure in the furnace When it is insufficient, due to the poor heat preservation effect, the temperature of the steel plate in the alloying furnace is difficult to meet the set requirements. At present, the control of the furnace pressure of the alloying furnace in the world is to add a flap at the outlet of the alloying furnace, and the furnace pressure is changed by the degree of closure ...

AI Technical Summary

Problems solved by technology

However, the traditional finite frequency domain controller design often adopts the method of weighting function, which will cause the following problems: firstly, it is a cumbersome process to find a suitable weight function; secondly, the introduction of weight function will increase the order of the system, increasing the The complexity of the system, the final weight function can only give an approximate description of the frequency range, so it is not accurate

The Kalman-Yakubovich-Popov (KYP) lemma is one of the important system theories. It can convert various characteristics of the dynamic system in the frequency domain into the form of linear matrix inequalities, but this lemma can only be used in the full frequency domain. Internally handles frequency domain inequalities

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