An alternative SCADA & AGC system development approach for a smaller size electric power system control

Abstract

Each EMS (Energy Management System) relies upon the SCADA system that gathers power system data, processes them and issues control commands. Among all the control functions of an EMS, the AGC (Automatic Generation Control) is the most important one. A SCADA system is characterized by geographical spread, a great amount of data, a complexity of belonging equipment, but by a very long period for the finalization and a very high investment costs, too. The long realization period compared with the extremely fast development of the available computer’s hardware and software on the world’s market, coupled with a permanent need for EMS upgrades caused by privatization of electric utility companies and deregulation of the electricity market, coerce some smaller size electric power companies to think in a different manner. This paper describes that manner - a unique control application, developed and implemented at the real power system. The specific feature of this control system is that it is based on the relatively poor set of power system data (around 70 input data), but a very good overall observability is achieved (around 300 output process informations). The second feature is the hardware – a single personal computer with the acquisition interface board in it as the SCADA host, and existing “hybrid” telemetric system for power system data gathering and AGC commands transport. Third - the choice of the Visual Basic language provides a lot of powerful features and unlimited possibilities for future easy–to-make upgrades and improvements, such as: object oriented code, encapsulation of functions, full GUI with animation, various communications including and Web-based one etc.