A main control feed-forward method for thermal power unit desuperheating water boiler

Abstract

The invention discloses a main control feed-forward method for a thermal power unit desuperheating water boiler. The method aims at the different influences of the desuperheating water of the superheater and the desuperheating water of the reheater on the main steam pressure and the load of the unit under the coordinated control mode of the unit respectively. Set the static feed-forward component and dynamic feed-forward component of superheater desuperheating water and reheater desuperheating water respectively. The pressure deviation corrects the dynamic feed-forward component, superimposes it into the boiler main control feed-forward of the unit coordination control system, and quickly adjusts the fuel amount to eliminate the superheater desuperheating water and reheater desuperheating water caused by the operation of the unit. The disturbance of the main steam pressure and the unit load can be controlled, and the dynamic response performance of the thermal power unit load and the stability of the steady-state load condition can be improved.

Description

technical field [0001] The invention relates to the field of boiler main control feedforward in a coordinated control system of a thermal power unit unit, in particular to a feedforward method for eliminating the action disturbance of desuperheating water by the boiler main control of a thermal power unit unit. Background technique [0002] The main steam temperature in a thermal power generation unit is a very important operating parameter. The control of the main steam temperature is a particularly critical part of the unit. With the power grid dispatching, there are higher requirements for the AGC adjustment function of the thermal power unit. In order to quickly respond to the AGC of the unit Load orders generally set a higher rate of load change. Due to the inherent large delay and large inertia characteristics of the boiler pulverization, combustion and heat transfer process, the main control of the boiler generally adopts the method of drastically increasing or decrea...

AI Technical Summary

Problems solved by technology

Due to the inherent large delay and large inertia characteristics of the boiler pulverization, combustion and heat transfer process, the main control of the boiler generally adopts the method of drastically increasing or decreasing the fuel volume and primary air volume to quickly change the combustion conditions of the boiler during the rapid load change process, thereby Improve the response speed of the boiler, but the main steam temperature fluctuates greatly during this process, followed by rapid changes in the superheater desuperheating water, and even the reheater desuperheating water (including accidental desuperheating water) also operates frequently, resulting in the main steam pressure and unit load. Obvious fluctuations occur, even in the high load section, the main steam pressure exceeds the alarm value due to the rapid injection of accident desuperheating water

[0003] Through the analysis of the operation data under the coordinated control mode of the unit, it is found that the rapid change of the desuperheating water of the superheater has a direct impact on the main steam pressure, and the rapid change of the desuperheating water of the reheater first causes the change of the inlet pressure of the intermediate pressure cylinder, which has a great impact on the actual pressure of the unit. The power generation has a direct impact, and the main control of the steam turbine quickly adjusts the opening of the high-pressure main steam regulating valve to eliminate the load deviation, thereby destroying the energy balance of the original organic furnace and causing fluctuations in the main steam pressure

In the traditional unit coordinated control system, the boiler master control is generally equipped with load dynamic feedforward to improve the response requirements of the boiler to the unit load, but it does not take into account the difference between the superheater desuperheating water and the reheater desuperheating water on the main steam pressure and load. Influence sets the corresponding boiler feed-forward component

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