This paper presents considerations relating to the monitoring of power plants to meet the requirements of transmission grids for information on their dynamic behavior.

Nearly all power plants today are supervised by Digital Control Systems (DCS) and most, though not all, of these DCS provide some form of trend recording. Nearly all plants now have a Plant Information (PI) system, either as an integrated part of their DCS or as a free standing unit. These trend recorders and PI systems can usually provide a fair picture of how a plant has behaved in normal slowly varying operation and through normal load change maneuvers.

However it is still difficult to find good data on the dynamic behavior of plants when they are disturbed by events on the grid. This suggests that the present standard monitoring elements in a power plant, the DCS and PI systems, are oriented to in-plant interests and are not well suited to the needs of the grid through which the plant delivers its product to market.

The consideration presented here, then, describes a monitoring system that is in addition to standard DSC and PI system functions.