On The Modularization Of Coal-fired Power Plant Control System

In modern coal-fired power plants, high temperature and high pressure units are broadly used. Their performance and reliability are mainly dependent on the control system. Distributed control system is widely adopted to design the control system due to its powerful control ability, operation simplicity, easiness to expanse and high reliability. Therefore, the control software which is in charge of control logic implementation in DCS is of great importance for power plant operation. This paper proposes a modular design approach for coal-fired power plant control system. Simulation results show that our approach can significantly reduce the workload and complexity of system design.The main contributions are listed as follows:1) Graph theory is used to give validation of the benefits of the modularized control system in comparison with unmodularized one, and the platform of coal-fired power plant control system’s modularization is set up.2) Common control strategies in coal-fired power plant are studied on the basis of engineering application requirements. Operation and secure issues should be considered when control strategies are applied in engineering, such as bumpless transfer between manual mode and automatic mode.3) Logic implementations of these control strategies are deduced. Analog control algorithms’schematic diagrams are drawn, and logic design of digital control algorithms are implemented.4) Modular design of coal-fired power plant control system is done. Encapsulation is implemented to ensure information shielding and modularization.5) During the implementation procedure of these algorithms, different methods are used to do this job as before, and the efficiency of these algorithms is increased with these methods.6) Verification platform for supercritical coal-fired power unit control system is established. Data communication between dynamic model of coal-fired power plant and control system is realized by using OPC software interface standard and database bridging. And then control strategies are tested by simulation in industrial control software.