IEEE 859-2018 pdf download

IEEE 859-2018 pdf download.IEEE Standard Terms for Reporting and Analyzing Outage Occurrences and Outage States of Electrical ‘ Transmission Facilities
NOTE—In generaL a component-based system of outage data collection for a system will be based on an inventors’ of components (the “population” which is intended to be exhaustive: every relevant portion of the system is a part of one and only one component. A comprehensive inventory of subcomponents is not usually developed, although an inventory of a particular class or catorv of subcomponents may be developed to support a particular study. Performance indices such cS failure rate are systematically calculated for all components in the relevant population but are rarely calculated for subcomponents. Examples include: line segments. towers. and buses might he subcomponents of a line section: hushing. tank. and windirn might be subcomponents of a transformer.
3.2.1 Line segment
A portion of a line section that has a particular typeof construction or isexposed to a particular type of failure, and therefore which may be regarded as a single entity for the purpose of reporting and analyzing failure and exposure data.
NOTE —A line segment is a subcomponent of a line section.
3.3 Unit
A group of components that which are functionally related and are regarded as an entity for purposes of recording and analyzing data on outage occurrences.
NOTE 1—A unit can be defined in a number of ways. For ample. it may be: (1) A group of components th,aj which constitute an operating entity bounded by automatic fault interrupting devices which isolate it from other such entifies for faults on any component within the group; (2) A group of components protected by and within the sensing zone of a particular system of protective relays. Examples include a transformer or an overhead line and associated terminal facilities switched with it; (3) A group of components induding a transmission line, one or more transformers s-upplied by the line, and a subtransmission or distribution network radially supplied from the transformer. These components are so configured that the subtransmission network is in the outage state during outage occurrences of the transmission line.
NOTE 2-A unit may be single-terminal, two-terminal or multi-terminal. A multi-terminal unit is connected to three or more terminals.
NOTE 3-It is recognized that certain components (for ex ample, circuit breakers) may be part of more than one unit.
NOTE 4- Different types of units inclu de transmission unit (overhead or cable), transformer unit,bus unit, and special units that consist of any equipment protected by separate breakers, such as shunt capacitors.
3.4 Terminal
A functional facility (substation, generating station, or load center) which incudes components such as bus sections, circuit breakers, and protection systems where transmission units terminate.
4. Component and unit states and events
Except as noted, the terms in this section apply to either “component” or “unit” performancereporting. However, it is assumed that in any particular context one viewpoint or the other is adopted, as in some instances a term may apply in one viewpoint but not another.
4.1 State .
Component or unit state is a particular condition or status of a component or a unit, which is important for outage reporting purposes.
4.1.1 In-service state
The component or unit is energized and fully connected to the system.
4.1.2 Outage state
The component or unit is not in the in-service state; that is, it is partally or fully isolated from the systerm.
NOTE 1-A unit may be in the outage state due to a failure of a component within the unit or due to the outage occurrence of another unit or component.
NOTE 2- A two-terminal transformer disconnected on one or both sides is in the ou tage state
NOTE 3- A three terminal overhead transmission line disconnected from one terminal is, as a unit,in the outage stage. However, the two overhead line sections still carrying power are, as components, in the in- service state. A drcuit breaker. which is not energized on either side. is in the outage state. Whether the circuit breaker is open or closed does not aft its in -service or Joutage state status.
4.1.2.1 Complete outage state
The component or unit is completely de-energized or is connected so that it is not serving any of its functions within the power system.
4.1.2.2 Partial outage state
The component or unit is at least partially energized, or is not fullyl connected to all of its terminals,or both, so that it is not serving some of its functions within the power system.
NOTE-A unit composed of a three-terminal line would be in the partial outage state if it were disconnected from one ter minal with two line sections still carrying power.IEEE 859 pdf download.IEEE 859-2018 pdf download