INTERNATIONAL JOURNAL OF CIRCUITS, SYSTEMS AND SIGNAL PROCESSING
Simulation of Power Plant Superheater Using
Advanced Simulink Capabilities
Pavel Nevriva, Stepan Ozana, Martin Pies
Abstract — The paper deals with simulation of both dynamics and control of power plant superheaters by means of Simulink Sfunctions. Superheaters are heat exchangers that transfer energy from flue gas to superheated steam. A composition of superheater, its input and output pipelines, and fittings is called a superheater assembly. Inertias of superheater assembly are often decisive for design of a steam temperature control system. Mathematical model of a
superheater assemble is described by sets of nonlinear partial differential equations. To analyze accuracy of the mathematical model, the system was agitated by test signals. Experiments carried out at the power plant were simulated mathematically. Data obtained by the measurement was compared with simulation results.
in . Mathematical model of a pipeline or a header can be
developed from the mathematical model of the heat exchanger
by introducing zero heat transfer coefficient from the
surrounding (making the pipeline isolated). The models
comprise many coefficients. Coefficients of pipelines and
headers are usually known with the relatively good accuracy. Let us consider the mathematical model of the superheater
assembly comprising superheater, its associated pipelines and pipe fittings. The accuracy of the model would depend on both the accuracy and correctness of coefficients of the model of the superheater. In this paper, the deterministic verification of the mathematical model of the superheater and its associated parts is presented. The verification process was as follows. The superheater assembly of operating 200 MW power plant
was agitated by the set of long term forced input signals. The dynamic responses were both measured and simulated. The
measured and calculated results were compared. The paper
presents results of selected experiments.
Keywords — modeling, simulation, Matlab&Simulink,
New high-temperature heat exchangers are being developed
nowadays. They are built using new constructions, they may
operate under new conditions or may use new materials and
working media, such as mixture of CO2/water vapor or
air/water vapor. New facilities and blocks for transformation of primary fossil energy into electrical energy are being
developed, with a focus on reducing CO2 as a greenhouse gas. There are several branches in development of such blocks.
One of them is concentrated on reducing CO2 in burning
process; this category covers development of systems with as high efficiency of primary energy transformation as possible. One of the examples can be energy blocks using Rankin –
Clausius cycle with supercritical parameters that have about 45% efficiency, or energy blocks working on so called vaporgas principals using combination of Brayton and Rankin – Clausius cycles that can reach up to 60% efficiency. The
interchange of energy from chemical to electrical one made in fossil thermal power plant is a complex process. Mathematical model of this process enables operator to optimize the control of the actual plant and the designer to optimize the design of the future plants.
There are many units that are situated in the main
technological chain of the thermal power plant. All of them
can be described mathematically and included in the
mathematical model of the plant. This paper deals with power plant heat exchangers, particularly with superheaters.
Superheaters are parts of the power plant boiler. They transfer heat energy from flue gas to superheated steam. Superheaters are connected to the other parts of the boiler by pipelines and headers. Inertias of heat exchangers and their pipelines are often decisive for the design of the power plant steam
temperature control system.
Mathematical model of the steam...
References: steady states according the measurements
Issue 1, Volume 5, 2011
IHI, Steam Generators, Technical Note of Ishikawajima-Harima Heavy
Industries Japan, 2004.
Cook R. D. at al., Applications of Finite Element Analysis, John Wiley
and Sons, 2002, ISBN 0-471-350605-0
Haberman R., Applied Partial Differential Equations with Fourier Series
and Boundary Value Problems, 4th Edition, Pearson Books, 2003,
Jaluria Y., Torreance K.E., Computational Heat Transfer. Taylor and
Francis, New York, 2003 ISBN 1-56932-477-5
Chen Chi-Tsong, System and Signal Analysis, Second Edition, Sundere
College Publishing, 1989
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