Pavel Nevriva

Mathematical Modeling of Turbine as a Part of Flexible Energy System

Mathematical modeling and simulation are important parts in design and development of complex systems implemented in industrial applications. This paper gives a description of basic structure, implementation of the model and simulation of turbine unit which is a part of Flexible Energy System with respect to parameters predefined by turbine producers. Turbines are basic elements of power stations for transfer of energy from heated medium to movement of generator. Their parameters and dependencies are crucial for complex power system, which is composed of given function elements. In this paper, the simulation of the elementary characteristic state values and their dependencies of the turbines are discussed. The developed mathematical turbine model is basic part of complex system of power plant where it serves as one of the main elements. Model of turbine unit is implemented as graphical user interface application by use of mathematical environment of MATLAB.

Control circuit of the heat exchanger and its verification on real operation data

The paper deals with the description of the control circuit of the power plant output superheater. Presented control circuit is modeled based on documentation provided by a power plant operator. Its verification is done through testing the mathematical model with real measured operational data. Output power plant superheater is described by a set of partial differential equations of the first order. These equations describe heat exchange between media through a wall with unspecified proportions. Equations are assigned into Simulink S-functions. The Simulink models act as mathematical model of the set consisting of the heat exchangers, on which the experiments are carried out. Actuating device of the regulating circuit is mathematical model of the injection water/steam which keeps the required temperature of the steam at the superheater output. This injection is also implemented as S-function in Simulink.

The predictive protective control of the heat exchanger

The paper deals with the predictive control applied to flexible cogeneration energy system FES. FES was designed and developed by the VITKOVICE POWER ENGINEERING joint-stock company and represents a new solution of decentralized cogeneration energy sources. In FES, the heating medium is flue gas generated by combustion of a solid fuel. The heated medium is power gas, which is a gas mixture of air and water steam. Power gas is superheated in the main heat exchanger and led to gas turbines. To protect the main heat exchanger against damage by overheating, the novel predictive protective control based on the mathematical model of exchanger was developed. The paper describes the principle, the design and the simulation of the predictive protective method applied to main heat exchanger of FES.