A control method for adjusting the amount of fuel into the boiler by using the oxygen content signal of the flue gas

Abstract

The invention relates to a control method for fuel supply, in particular to a control method for adjusting the amount of fuel fed into a boiler by utilizing the oxygen content signal of flue gas. The method includes the following steps: establishing a control law that is better than the optimization target according to the load and temperature distribution, obtaining the optimal flue gas oxygen content from the optimal control law, and making a calculation based on the current flue gas oxygen content signal and the optimal flue gas oxygen content. The offset calculation yields a total fuel correction signal. According to the total fuel correction signal, the amount of fuel into the furnace is precisely controlled. Incremental PID algorithm is selected for the control operation. According to the optimal change rule of flue gas oxygen content with load and steam temperature, the present invention intervenes in advance and accurately on the amount of fuel, improves the response speed of coal-fired unit load; improves the safety and stability of the boiler operation process, Effectively improve the thermal efficiency of the power plant and reduce energy consumption.

Description

technical field [0001] The invention relates to a control method for fuel supply, in particular to a control method for adjusting the amount of fuel fed into a boiler by utilizing the oxygen content signal of flue gas. Background technique [0002] Effectively improving the thermal efficiency of power plant operation and reducing energy consumption has always been an inevitable requirement for the development of my country's economy and power industry. Among them, whether the control and adjustment method of air volume and fuel volume is effective is an important factor affecting the thermal efficiency of boiler combustion. For coal-fired power plants, the main task of the combustion control system is to control the amount of fuel during operation to meet the requirements of steam pressure or load output, and to adjust the air supply volume through the deviation of flue gas oxygen content, while ensuring the boiler operation process. Safety, stability and economy. [0003] ...

AI Technical Summary

Problems solved by technology

This control method is based on the control strategy of "air-to-coal ratio" and "water-to-coal ratio", and adopts the adjustment method of relevant parameter deviation-feedback-output to realize the adjustment of fuel into the furnace. The detection signal and the control of a single loop do not analyze and utilize the "massive data" in each operating condition of the unit, and cannot timely analyze the fuel volume, air volume, damper opening, water supply, etc. according to the coal quality and load changes. Coordinated optimization control cannot adapt to rapidly changing load conditions, and cannot adapt to changes in regulation performance caused by changes in the characteristics of external equipment such as fans, and the system has poor anti-disturbance ability

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