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REQUIREMENT  Approval item: 

Application concept

The recloser object is being adjusted to reflect the new simplified switch implementation. Rather than being a sub-class of switch, it will now be an add-on device providing functionality to switches.

Use Case

Updated recloser objects will be set up to open/close switch objects, based on the requirements below. This will maintain the legacy "simplified recloser" support (QSTS studies and reliability-driven IEEE 1366 metrics), as well as the updated current-checking functionality of feature/990. The basic function of the recloser is to provide fault-breaking and section reconfiguration capabilities, typically in conjunction with the reliability module.

General Requirements

The updated recloser is meant manipulate switch objects to open a section of a system when the proper fault current was registered through the device. It will either explicitly attempt reclosing counts (deltamode), or register them as momentary interruptions (QSTS).

The final implementation of the recloser will meet these requirements:

R1

The recloser will be interface with a switch object.

R1.1

Recloser will require a switch object as a parent

R1.2

Recloser open/close actions will be sent to the switch object, which will perform the action

R1.3

Recloser will use base link class connections to obtain current (Amps) values for actions

R2

The recloser will support two modes of operation

R2.1

The recloser will support a traditional mode of operation

R2.1.1

Traditional mode will support old quasi-steady-state time series (QSTS) approaches from prior GridLAB-D versions/files

R2.1.2

Traditional mode will behave like "pre-fault" and "post-fault" existing analysis - the transient portion will not be modeled.

R2.1.3

Traditional mode will require reliability, and related link-based functions, to open the recloser

R2.1.3.1

Recloser will not actually actuate the switch for the retry counter.

R2.1.3.2

Reliability will utilize the retry counter to influence IEEE 1366 metrics, such as MAIFI

R2.1.4

No fault current sensing or acting will occur in traditional mode. Any fault current calculations are informational only.

R2.2

The recloser will support a local/individual-based mode of operation

R2.2.1

The recloser will use local information to determine if it should open or close.

R2.2.1.1

The recloser will monitor current passing through it and determine if it is above the define protection threshold.

R2.2.1.2

The recloser will utilize time-over-current-capability (TCC) curves to determine trip points

R2.2.1.3

The recloser will support two TCC sets - a fast and a slow curve.

R2.2.1.4

The recloser will monitor the duration of exceeded current and determine if an action is needed (based on TCC)

R2.2.2

The recloser will have fault-current-breaking capabilities

R3

The recloser will work in both QSTS mode and deltamode

R3.1

The recloser will retain the same capabilities (traditional vs. local/individual) in both QSTS and deltamode simulation.

R3.2

The recloser will self-trigger deltamode, if available

R3.2.1

The recloser will only self-trigger deltamode in local/individual mode

R3.2.2

Deltamode triggering will be performed if an expected TCC time limit will occur at a partial second of the simulation

R4

Upon retry lockout, the recloser will need to be manually reclosed via a player or external method

See also