Multi-model prediction control method of carbon dioxide after combustion capture system

Abstract

The present invention discloses a multi-model prediction control method of a carbon dioxide after combustion capture system. The prediction control method takes the carbon dioxide after combustion capture system based on the chemisorptions as a controlled object, takes the barren liquor valve opening and the turbine low pressure cylinder steam extraction valve opening as the system control input, takes the carbon dioxide capture rate and the reboiler temperature as the system output, and comprises the steps of firstly, based on a sub-space identification method, utilizing the data generated by the system operation to establish a local state space model of the system at different working condition points; then using a gap measurement method to research the nonlinear distribution of the controlled object; and further establishing a prediction controller at an appropriate local working condition point, designing a degree of membership function to weight and combine, and establishing a multi-model prediction control system of the carbon dioxide after combustion capture system. The method of the present invention has a good global nonlinear control capability, can adapt to the large-range variable working condition demands of the system effectively, rapidly tracks a carbon dioxide capture rate setting value, and enables the deep, rapid and flexible operation level of the carbon dioxide capture system to be improved.

Description

technical field [0001] The invention relates to the technical field of predictive control methods, in particular to a post-combustion CO 2 A multi-model predictive control approach for capture systems. Background technique [0002] With the increasing severity of the greenhouse effect and related climate and ecological problems, reducing CO emissions 2 It has become a key measure for the international community to deal with climate change. As the main equipment for power supply, thermal power units are CO 2 The most stable and concentrated emission source, 30%-40% of the world and 40%-50% of my country's CO 2 Emissions come from thermal power units. While actively developing new energy technologies and striving to improve the power generation efficiency of thermal power units, the CO of thermal power units 2 Capture is recognized by many authoritative organizations as the realization of large-scale CO in the next 30 years 2 The most direct and effective technical means...

AI Technical Summary

Problems solved by technology

However, with CO 2 The capture equipment operates under a wide range of variable working conditions, and its system presents strong nonlinear characteristics, which leads to a decrease in the control performance and stability of traditional predictive controllers designed based on linear models

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