Steam Pressure Control of 1 000MW Ultra-Supercritical Coal-Fired Power Unit Based on Multi-Model Predictive Control

doi:10.1007/s12204-018-2015-9

Abstract

Abstract: Ultra-supercritical (USC) coal-fired unit is more and more popular in these years for its advantages. But the control of USC unit is a difficult issue for its characteristic of nonlinearity, large dead time and coupling among inputs and outputs. In this paper, model predictive control (MPC) method based on multi-model and double layered optimization is introduced for coordinated control of USC unit running in sliding pressure mode and fixed pressure mode. Three inputs (i.e. valve opening, coal flow and feedwater flow) are employed to control three outputs (i.e. output power, main steam temperature and main steam pressure). The step responses for the dynamic matrix control (DMC) are constructed using the three inputs by the three outputs under both pressure control mode. Piecewise models are built at selected operation points. In simulation, the output power follows load demand quickly and main steam temperature can be controlled around the setpoint closely in load tracking control. The simulation results show the effectiveness of the proposed methods.

Key words: ultra-supercritical| coordinated control| multi-model| model predictive control| steam pressure control

摘要： Ultra-supercritical (USC) coal-fired unit is more and more popular in these years for its advantages. But the control of USC unit is a difficult issue for its characteristic of nonlinearity, large dead time and coupling among inputs and outputs. In this paper, model predictive control (MPC) method based on multi-model and double layered optimization is introduced for coordinated control of USC unit running in sliding pressure mode and fixed pressure mode. Three inputs (i.e. valve opening, coal flow and feedwater flow) are employed to control three outputs (i.e. output power, main steam temperature and main steam pressure). The step responses for the dynamic matrix control (DMC) are constructed using the three inputs by the three outputs under both pressure control mode. Piecewise models are built at selected operation points. In simulation, the output power follows load demand quickly and main steam temperature can be controlled around the setpoint closely in load tracking control. The simulation results show the effectiveness of the proposed methods.

关键词: ultra-supercritical| coordinated control| multi-model| model predictive control| steam pressure control

CLC Number:

TP 13

WANG Guoliang *(王国良), DING Baocang (丁宝苍), YAN Weiwu (阎威武). Steam Pressure Control of 1 000MW Ultra-Supercritical Coal-Fired Power Unit Based on Multi-Model Predictive Control[J]. Journal of Shanghai Jiao Tong University (Science), 2019, 24(1): 86-93.

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