Implementation of an AGC-algorithm in different power systems and on different control levels

The scheduling and control of power generation are vital aspects in the daily operation of power systems. Their overall objective is to control the electrical power output generated so as to supply ever changing customer demand for power as economically as possible. An automatic generation control (AGC) program operating within a computer control centre can provide the necessary means to the dispatchers to perform this continuous task. The authors present an overview of the functional requirements for generation control software, and design principles enabling flexibility and easy maintenance when integrating such a closed loop, time critical function into a control system. Operating philosophies used in various countries to which ABB has supplied VAX based EMS systems, and how the basic AGC software package is used to satisfy the required criteria, are discussed