A multi-step prediction method for over-temperature warning of heating surface tube wall of ultra-supercritical boiler

Abstract

The invention relates to a multi-step prediction method for early warning of overtemperature of the tube wall of the heating surface of an ultra-supercritical boiler, comprising: step 1, collecting training data in the training stage, and constructing a time series network model after preprocessing the collected training data And carry out offline training; step 2, collect the input data in the use stage as the input of the time series network model, and obtain the prediction result of the metal wall temperature data. The beneficial effects of the present invention are: the temperature of the tube wall on the heating surface can be predicted in advance, and guidance can be provided for over-temperature control; longer time-series characteristic information can be captured, and the prediction accuracy can be improved; by sinusoidal encoding of time, the transition of each day can be smoothed, It is more in line with the actual operating conditions; it can not only solve the problem that the sensor cannot work for a long time by direct measurement, but also realize the prediction of wall temperature at different positions; it can easily add the latest data and retrain the model, and has good anti-interference.

Description

technical field [0001] The invention belongs to the technical field of boiler safety, and in particular relates to a multi-step prediction method for early warning of overtemperature of a tube wall on a heating surface of an ultra-supercritical boiler. Background technique [0002] With the continuous improvement of power demand and energy saving and emission reduction requirements, the steam temperature and pressure of boilers are constantly increasing. Ultra-supercritical boilers and superheaters work in harsh environments, which are more likely to cause over-temperature tube explosion. [0003] The temperature of the tube wall on the heating surface of the ultra-supercritical boiler is high, the flue gas flow rate is large, and the working conditions are harsh, so the temperature sensor cannot measure the temperature of the metal tube wall for a long time, and the temperature change of the tube wall is hysteretic, nonlinear, non-stationary, and strongly coupled. character...

AI Technical Summary

Problems solved by technology

The patent No. 201010183756.6 is equipped with a series of thermocouple sensors on the pipeline to collect the boiler heating surface wall temperature signal, which optimizes the sensor layout; however, the internal environment of the ultra-supercritical boiler is harsh and the temperature is high, and the sensors cannot work for a long time and can only monitor current wall temperature

Patent No. 201611123426.1 collects flue gas and steam-water variables through the boiler DCS system or SIS system, and calculates the metal wall temperature through empirical formulas. This method has a large error in calculating the wall temperature and cannot be predicted in advance

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