Decoupling design of the load control system in a single-extraction heating unit and its dynamic response characteristics

doi:10.3969/j.issn.1674-1951.2021.03.007

Abstract

Abstract:

The coupling of heat load and electric load in heating units makes it difficult to adjust the load independently. The adjustment cannot meet the requirements of Automatic Generation Control（AGC）. Taking increments equation to linearized the mathematical model of the heating unit, the static relative gain between each input and output of the heating unit is calculated. Then, the variables are paired. On this basis, the control system is decoupled with the help of multivariable decoupling theory. The dynamic characteristics of thermal and electric load regulation made by the control system before and after the decoupling are analysed. The results show that the optimized control system can improve the regulation of heat and electric load, and optimize the regulation characteristics of heating units.

Key words: heating unit, decoupling of thermal and electric load, relative gain, control system, multivariable decoupling, variable load, dynamic response

CLC Number:

TK323

QIN Haishan, LUAN Congchao, HOU Xiaoning, CHONG Daotong. Decoupling design of the load control system in a single-extraction heating unit and its dynamic response characteristics[J]. Huadian Technology, 2021, 43(3): 40-47.

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静态相对增益	数值
λ₁₁	0.981 6
λ₁₂	0.018 4
λ₁₃	0
λ₂₁	0.015 4
λ₂₂	0.981 7
λ₂₃	0.002 9
λ₃₁	-0.002 9
λ₃₂	0
λ₃₃	1.002 9