AN ADVANCED TRANSPORTABLE OPERATOR TRAINING SIMULATOR J.G. Waight, K. Nodehi, M. Rafian, H. Van Meeteren* A. Bose Empros Systems International Arizona State University R. Wasley E. Stackfleth E. Dobrowolski Macro Corporation Hughes Training Systems Philadelphia Electric Company ABSTRACT widely accepted in other contexts, was first introduced as a tool for operator training with the announcement and demonstration Since the introduction of the first Dispatcher Training of the Dispatcher Training Simulator (DTS) at PICA in 1977 [1]. Simulator (DTS) at PICA in 1977, DTS systems have evolved in This DTS had limited capabilities in terms of model size and in scope, complexity and performance. This paper outlines the the fidelity of the simulation, the User Interface, and the control design of an advanced, transportable Operator Training functions. Simulator (OTS) which was developed as part of EPRI research project 1915-2. Advanced modeling technology and instructor In the following years many vendors introduced DTS systems, capabilities are described along with training examples which mostly integrated with new energy management systems [2], demonstrate the capabilities of this OTS. [3], [4], [5]. Model sizes grew, and improvements were made in the fidelity of the training devices. Yet certain limitations persisted especially in the area of simulation of complex INTRODUCTION voltage phenomena, in instructor tools, and in capabilities for trainee evaluation. The Electric Power Research Institute During the past few decades, the complexity of the job of the undertook the development of an advanced Operator Training power system control center operator has increased Simulator (OTS) with improvements over other simulators then dramatically. Several factors have contributed to this change in on the market. Research Project 1915-1, [6] laid out the complexity. The utilities of the United States have become guidelines which could be used to develop a such a simulator. increasingly interconnected, coalescing today into three major interconnections. Later environmental and economic factors This paper reports the research and development of the advanced combined to favor the construction of new generating stations transportable simulator. at sites remote from existing load centers and with limited transmission access to these load centers. The increase in the cost of petroleum fuels and the availability of relatively cheaper REQUIREMENTS hydroelectric power from Canada has led to transmission of electric power over long distances over a strained transmission The overall requirement was to develop an Operator Training network. During the late 1980's, large unforecasted increases in Simulator suitable for simulation of normal, emergency, and peak summer demand has further aggravated the situation. The restorative conditions of an electric power system and to have a nature of operating problems has changed in many instances useful simulation tool for operations, planning and after-the­ from concern about thermal problems, to concern over fact analysis. The overall requirement was subdivided into five VoltNAR coordination and the potential for voltage collapse. specific requirements. All of these factors have increased the complexity of the jobs of The first requirement was to develop simulation capabilities system control center operators. To meet these challenges, needed for system operator training. This led to the utilities have procured and installed computer based SCADA and development of requirements and specifications for models and EMS systems. Sophisticated tools such as state estimators, algorithms suitable for simulation based training of operators contingency analysis, and optimal power flows have been in emergency conditions including complex voltage placed in the hands of system operators as operating aids in the phenomena in real time. Fidelity requirements were stated in new environment. These new tools have brought with them the two ways. The simulator must behave as the real world does as need for more training of system operators in the use of these seen by the operator. The man machine interface and the tools, especially during emergency operating conditions. control functions used by the trainee must be the same as those used by the operator in the Energy Management System (EMS). At the same time other economic factors and the deregulation of utilities have led to the downsizing of utility operations staff. The second requirement was to develop the OTS on a practical, In many cases early retirement options may lead to the loss of realizable platform. This meant that the OTS must run on veteran operators with many years of operating experience. commercially available, all digital computer hardware. Custom These positions are then filled with junior operators with less built hardware, such as analog or hybrid simulators, was not on-the-job experience. considered as a development option. All of these factors have accentuated the need for training The third requirement was to develop improved instructor system control center operators in all phases of system capabilities. These capabilities support the instructor in operations: normal operations, emergency operations, and in preparing the training sessions, executing the training system restoration. Simulation based training, which has been sessions, and evaluating the performance of the trainee. The fourth requirement was to develop a simulator which is *Mr. Van Mecteren is now with Energy Control Consultants. transportable and applicable to a broad range of utilities. This objective was established to ensure that the developed OTS is of benefit to as many utilities as possible. The fifth requirement was to demonstrate and evaluate the OTS in the operational environment of a host utility. Philadelphia Electric was selected by EPRI as the result of a formal process which included proposal solicitation, evaluation, and selection. Reprinted from IEEE Proceedings of the PICA Conference, pp. 164-170, May 1991. 278 OTS CONFIGURATION Trainee Consoles Primary Secondary CPU CPU The OTS is comprised of three major hardware components: the (EMS) (CCM) Power System Modeling (PSM) computer, the Control Center Modeling (CCM) computer and the Instructor Position(s) (lP). Communications Processors The PSM computer is used to simulate the Power System Modeling and Educational Subsystems. The Power System Modeling subsystem consists of the models for the electrical network, generating units, prime movers, loads, relays, local Controllers controls for the system, the AGC systems of external companies, and possible power pool controllers. The Disk Educational Subsystem allows the instructor to set up events InstructorConsoles which occur during the simulation. The PSM has an instructor PSM interface that allows personnel other than the system control Tape CPU center operator to control the electrical power system. Typically, such persons include substation operators, power Line plant operators, and system control operators of neighboring Printer utilities and possible power pools. The instructor interface is provided through the Instructor Position(s). The PSM also has ~ = New EqlApmenl an interface to the CCM. This interface includes simulations of the SCADA RTU traffic and of inter-utility data links. o = Exlslng EquIpment The CCM computer contains a model which replicates the user Figure 1. Generic Configuration of OTS utility's EMS. Functions included in the user utility's EMS are modified to communicate data to and from the PSM instead of Software Implementation the RTUs and other utility or power pool computer systems. These functions typically include: One of the requirements was to develop an OTS that is transportable and can be made available to a broad range of Alarm Processor utilities either as part of a new EMS or an an extension to an Data Acquisition existing EMS. In order to fulfill these requirements a Economic Dispatch configuration was selected whereby the CCM could be Interchange Scheduling implemented on redundant control center hardware and the PSM Load Frequency Control and IP could be implemented on additional hardware. A further Man-Machine Interface Network Analysis Applications requirement was that the PSM software could be ported from the Scheduling Applications selected hardware platform to other hardware with minimal Supervisory Control efforts. At the time of the design, software standards for portable operating systems, user interfaces, and data base The Instructor Position is based on a workstation. This management systems were not widely accepted nor available. workstation has features to support instructor activities during simulation. These features include: In the OTS design the portability requirement was satisfied by the construction of an OTS Executive which includes the Instructor MMI necessary subset of the capabilities available in proprietary Education subsystem interface EMS executives. The PSM software contains interfaces to the Logging OTS Executive which in tum is interfaced to the proprietary operating system available on the selected hardware. Figure 1 shows the generic configuration of the OTS. The PSM software is made up of a number of tasks which are In order to implement the OTS software, the Central Processing executed concurrently, both on a periodic and demand basis. Unit (CPU) used for the PSM should be a computer with the The OTS Executive was developed in ANSI Fortran to schedule following main features as a minimum: tasks and