Control of power flow between systems

When MW capacity and MWh energy interchange contracts are made between neighbouring utilities, economic benefits are expected by both parties. If energy interchange is arranged as part of the normal scheduling of generators for economic dispatch, then to fulfil contracts entered into in advance, power flow levels and their duration must be scheduled across interconnecting transmission circuits. Maintaining the scheduled flows is part of the duties of the system control engineer, but the costing of the use of the system for them is an economic operational planning problem. The author outlines methods available to the control engineer to meet scheduled interchange flows on a high voltage transmission system