Many large-scale processes like refineries or power generation plant are constructed using the multi-vendor system and a main co-ordinating engineering contractor. With such a methodology. the key process units are installed complete with local proprietary control systems in place. Re-assessing the so called lower level control loop design or structure is becoming less feasible or desirable. Consequently, future comp~titive gains in large-scale industrial systems will arise from the closer and optimised global integration of the process sub-units. This is one of the inherent commercial themes which motivated the research reported in this monograph. To access the efficiency and feasibility of different large-scale system designs, the traditional tool has been the global steady-state analysis and energy balance. The process industries have many such tools encapsu­ lated as proprietary design software. However, to obtain a vital and critical insight into global process operation a dynamic model and simulation is necessary. Over the last decade, the whole state of the art in system simulation has irrevocably changed. The Graphical User Interface (G UI) and icon based simulation approach is now standard with hardware platforms becoming more and more powerful. This immediately opens the way to some new and advanced large-scale dynamic simulation developments. For example, click-together blocks from standard or specialised libraries of process units are perfectly feasible now.

Inhalt

1 CC and CHP Systems: An Introduction.- 1.1 Introduction.- 1.2 Power Plants with Steam Turbines.- 1.3 Power Plants with Gas Turbines.- 1.4 Combined Heat and Power Configurations.- 1.4.1 CHP Configuration with a Steam Turbine.- 1.4.2 CHP Configuration with a Gas Turbine.- 1.5 Combined Cycle Configurations.- 1.6 The Main Components of Power Plant.- 1.6.1 Steam Turbine.- 1.6.2 Boiler.- 1.6.3 Gas Turbine.- 1.6.4 Condenser.- 1.6.5 Feedwater System.- 1.6.6 Miscellaneous Components.- 1.7 Operational Procedures.- 1.7.1 Operational Regimes.- 1.7.2 Main Control Loops.- 1.7.3 Safety Conditions.- 1.8 Block Diagrams for CC and CHP Schemes.- 1.8.1 CHP installation with Steam Turbine.- 1.8.2 CHP installation with Gas Turbine (or Diesel Engine).- 1.8.3 CHP installation with CC Process.- 1.8.4 A Component Based Block Diagram.- 1.8.5 Conclusion.- 1.9 Case Study: Skegton Unit.- 1.9.1 Introduction.- 1.9.2 Block Diagrams.- 1.10 Conclusions.- 1.11 References for the Chapter.- 2 Power Generation Plant Control.- 2.1 Introduction.- 2.2 Some Technological Background.- 2.2.1 DCS Architectures.- 2.2.2 DCS Technology.- 2.2.3 Technological Implications and Potential.- 2.3 Power Generation Plant Control.- 2.3.1 Task of Low Level Controllers.- 2.3.2 Process Variable Constraints.- 2.3.3 Top Level Control Considerations.- 2.4 Control of Skegton Unit.- 2.4.1 The Main Control Problems.- 2.4.2 Local Control Loops.- 2.5 Supervisory Control Problems Summarised.- 2.5.1 Load Management Strategies.- 2.5.2 Performance Optimization.- 2.5.3 Dynamic Set-Point Manoeuvres.- 2.5.4 Low Level Control Structures.- 2.5.5 Conclusions.- 2.6 Chapter Conclusions.- 2.7 References for the Chapter.- 3 Simulation Tools.- 3.1 Introduction.- 3.2 Engineering System Types.- 3.2.1 Discrete System Simulation.- 3.2.2 Process Control Systems.- 3.2.3 General Dynamical Systems.- 3.3 Dynamic System Simulation Tools: A Review.- 3.3.1 Icon Based Simulation.- 3.3.2 Simulation Tools: A Short Survey.- 3.4 An Assessment Exercise.- 3.4.1 The Assessment Basis.- 3.4.2 A Simple Boiler Model Test Case.- 3.4.3 The Assessment Results.- 3.5 Conclusions.- 3.6 References for the Chapter.- 3.7 Software Suppliers.- 4 Process Models.- 4.1 Introduction.- 4.2 State Space Modelling.- 4.3 Skegton Unit Component Models.- 4.3.1 Boiler.- 4.3.2 Gas Turbine.- 4.3.3 Steam Turbine.- 4.3.4 Condenser.- 4.3.5 Feedwater System.- 4.3.6 Electrical Generator.- 4.3.7 Gas Merge and Split.- 4.4 Controller Descriptions.- 4.4.1 Introduction.- 4.4.2 Criteria Applied to Eliminate Low Level Control Loops.- 4.4.3 Boiler Control Configuration.- 4.4.4 Gas Turbine Control Configuration.- 4.4.5 Steam Turbine Control Configuration.- 4.4.6 Condenser Control Configuration.- 4.4.7 Feedwater System Control Configuration.- 4.5 Conclusions.- 4.6 References for the Chapter.- 5 Simulation Studies.- 5.1 Introduction.- 5.2 Module Library Description.- 5.2.1 The Boiler.- 5.2.2 The Gas Turbine.- 5.2.3 The Steam Turbine.- 5.2.4 The Condenser.- 5.2.5 The Feedwater System.- 5.2.6 The Electrical Generator.- 5.2.7 Gas Merge and Splitting Process.- 5.2.8 The Valve (Gas).- 5.3 Skegton Unit Simulation Results.- 5.3.1 Introduction.- 5.3.2 Skegton Unit Sizing Data.- 5.3.3 Skegton Unit Simulation Data.- 5.3.4 Skegton Unit Dynamic Response Tests.- 5.3.5 An Example of Using MATRIXx to Determine a Static Model.- 5.3.6 Selected Frequency Responses for Sketon Unit - Bode Diagrams.- 5.4 Conclusions.- 5.5 References for the Chapter.- 6 Conclusions.- 6.1 Summary Conclusions.- 6.2 The Future Research Directions.- Appendix 1 Skegton Unit Simulation Data.- Appendix 2 Polynomial Representation for Saturated Steam and Water Conditions.