ABSTRACT
An electric power grid is a complex interconnected arrangement of systems that have to work together to deliver electricity, while maintaining synchronized operation of all its generating units. A power grid is a sprawling network involving many separate utilities; each independent in its own control area and regulated by local bodies, to meet the demand for electricity reliably and economically. These organizations have to coordinate to operate the interconnected system, and this coordination can take many forms, from a loose agreement of operational principles to a strong pooling arrangement of operating together. In a loosely coordinated grid, each balancing utility is responsible for operating its own portion while exchanging all relevant information with its partners. Alternatively, groups of utilities may set up a pool where operational decisions may be made centrally and then implemented by each utility. Power-system operations can be divided into three stages: operations planning, real-time control, and after-the-fact accounting.
