**3.3 Operator Module**

The Operator Module is a replica of the real operation station, and it is formed by the IPD (operation interfaces) that links the control and process models providing and receiving variables between them. Other functions of the module are to call the operation modes of each IPD component (valves, pumps, buttons, etc.); to refresh each IPD periodically; and to coordinate the sequence of events in the operation consoles.

A total of 20 control screens, including the index, and as many tendencies displays as needed are available for the operator. As an example, the blade path and exhaust temperatures control screen of the operator, a replica of the Distributed Control System (DCS), is shown in Figure 5.

Fig. 5. Combustor blade path and exhaust temperatures control screens.

console and functions for the operators consoles. All the information is configurable for each

The global variables memory area is a dynamic memory created when the simulation starts. This special area is formed from information of data base and contains the direction of global variables for both models process and control. This function allows to modify and to

The Operator Module is a replica of the real operation station, and it is formed by the IPD (operation interfaces) that links the control and process models providing and receiving variables between them. Other functions of the module are to call the operation modes of each IPD component (valves, pumps, buttons, etc.); to refresh each IPD periodically; and to

A total of 20 control screens, including the index, and as many tendencies displays as needed are available for the operator. As an example, the blade path and exhaust temperatures control screen of the operator, a replica of the Distributed Control

coordinate the sequence of events in the operation consoles.

Fig. 5. Combustor blade path and exhaust temperatures control screens.

application that uses the *MAS*.

System (DCS), is shown in Figure 5.

consult variables.

**3.3 Operator Module** 

The flash movies have both, static and dynamic parts. The static parts are constituted by drawings of some particular control screens that are fixed on the screen. The dynamic parts are configured with graphic components stored in a library which are related to each one of the controlled equipments (pumps, valves, motors, etc.). These components have their own "moving" properties and they are employed during the simulation execution.

The main parts of the operator module are:


As a result of these functions, the student perceives his actions and simulator response in a very close way as it happens in the actual plant.

## **3.4 Models sequencer**

The models sequencer coordinates the execution of mathematical models in a parallel scheme on a distributed architecture of PCs or with multi-core equipment. This module also has a group of methods to initialise variables belonging to the mathematical models. These values (initial conditions) represent a particular state of the plant and are located in the global variables memory area.

The models themselves and its mathematical treatment are explained in Section 5.1.

### **3.5 Instructor console functions**

The Instructor console is presented in Figure 6.

Fig. 6. View of the instructor console.

The Instructor console has menus to activate different functions according the instructor necessities. The main functions are listed in this section.

Run/Freeze. The instructor may start or freeze a dynamic simulation session.

Initial conditions. The instructor may select an initial condition to initiate the simulation session, either from the general pre-selected list of initial conditions or from their own catalogue. Each instructor has access up to 100 initial conditions. Also in this function it is possible to create an initial condition or to erase an old one. As a instructional help, the

Models for Training on a Gas Turbine Power Plant 221

For an operators training simulation, the objective is to reproduce the behaviour of, at least, the reported variables in the plant control station in such a way the operator cannot distinguish between the real plant and the simulator performance considering both, the value of the parameters and their dynamics. The models were designed to work for all plant conditions, from 0% to 100% of load including all the possible transients that may be present during an operational session in the real plant. In order to accomplish with these objective, the "ANSI/ISA-S77.20-1993 Fossil-Fuel Power Plant Simulators Functional Requirements"

The gas turbine power plant was divided into a set of systems to be simulated, trying these to coincide with the real plant systems. A modelled system is a mathematical representation of the behaviour of the variables of the real system. The model of a simulated system (MSS) in the simulator responds to the operator's actions in the same way that the real system

Each MSS is divided in algebraic and ordinary differential equations (AE and ODE, respectively). The AE may have to be solved simultaneously if necessary but they are independent of their ODE. For this work, different solution methods were adapted for linear and non-linear equations: Newton-Raphson, Gaussian elimination and bisection partition search. They are used depending on the characteristics of each particular model. The final

Fig. 7. Simplified diagram of a gas turbine power plant.

norm was followed and adopted as design specification.

does, in tendency and time.

**5. Developing of the gas turbine models 5.1 Execution of the models in the simulator** 

simulator is capable of getting the automatic snapshooting function, every 15 seconds and may be configured up to a frequency of 10 minutes.

Simulation speed. From the beginning of the simulation session the simulator is executed in real time, but the instructor may execute the simulator up to ten times faster or ten times slower than real time.

Malfunctions. It is used to introduce, modify, or remove a simulated failure of plant equipment. For the case of the gas turbine simulator, there are 98 available malfunctions. Examples of malfunctions are: pumps trips, heat exchanger tubes breaking, heaters fouling, and valves obstructions. For the binary malfunctions (like trips), the instructor has the option to define its time delay and its permanence time. For analogical malfunctions (like percentage of a rupture), besides the mentioned time parameters, the instructor may define both intensity degree and evolution time.

Remote functions*.* The instructor has the option to simulate the operative actions not related with actions on the plant performed from the control screens. These actions are associated with the local actions made in the plant by auxiliary workers. Examples of them are: to open/close valves and to turn on/off pumps or fans. There are more than 200 of them and they may have time and intensity degree parameters as instructor options.

External parameters. The external conditions such as: atmospheric pressure and temperature (dry and wet bulb), voltage and frequency of the external system, fuel composition, gas fuel delivery pressure, etc. can be modified by the instructor.

Repetition. Simulation session may be repeated, exactly as operated by the trainees, including the trainer actions, as many times as the instructor considers it necessary. An action registration is the basis for this function.

Automatic exercises. This is a function that allows to create a file indicating a series of instructor functions to be automatically tripped along the simulation scenario in defined times.

Development tools. The simulator has implemented some others helpful tools to use during simulation session development, for example: to monitor and change on line the value of any selected list of global variables, tabulate any selected list of variables and plot them.
