A Three-Impulse Control Method for Reducing Boiler Liquid Level Overshoot

Abstract

The invention provides a three-impulse control method reducing the boiler liquid level overshoot. The opening degree of a water supply adjusting valve is controlled based on the three-impulse controlprinciple; by means of the control method, a variable vapor-water mismatch amplification coefficient is used for changing a feed forward signal, when the absolute value of the vapor-water mismatch rate is reduced, the vapor-water mismatch amplification coefficient is reduced, the specific gravity of the feed forward signal is greatly reduced, the frequent action of the water supply adjusting valvedue to small disturbance is avoided, the problem that the anti-interference capability of a dynamic feed forward control system is poor is solved, production energy consumption is reduced, and the service life of the water supply adjusting valve is prolonged; and when the absolute value of the vapor-water mismatch rate is increased, the vapor-water mismatch amplification coefficient is increased,the specific value of the feed forward signal is increased, a controller can rapidly change the water supply amount, dynamic balance of the water supply amount and steam flow is maintained, and the liquid level overshoot phenomenon is reduced.

Description

technical field [0001] The invention relates to the technical field of boiler water level control, in particular to a three-impulse control method for reducing boiler liquid level overshoot. Background technique [0002] Industrial boilers are important thermal power equipment, widely used in textiles, printing and dyeing, pharmaceuticals, chemicals, oil refining, etc., and are indispensable equipment for production and life in today's society. In the production process, if the water level is too high, it will destroy the normal operation of the steam-water separation device, resulting in water in the steam, increasing the scaling on the wall of the superheater. If the water level is too low, it will destroy the water cycle and cause the water-cooled wall tube to burst. If the liquid level of the boiler has a large overshoot or a large shock, it is easy to cause poor product quality, and in serious cases, a safety accident will occur. When the feed water flow rate, especial...

AI Technical Summary

Problems solved by technology

In the production process, if the water level is too high, it will destroy the normal operation of the steam-water separation device, resulting in water in the steam, increasing the scaling on the wall of the superheater. If the water level is too low, it will destroy the water circulation and cause the water-cooled wall tube to burst

If the liquid level of the boiler has a large overshoot or a large shock, it is easy to cause poor product quality, and in serious cases, a safety accident will occur

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