REQUIREMENT Approval item:
Application concept
The sectionalizer 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 sectionalizer objects will be set up to open/close switch objects, based on the requirements below. This will maintain the legacy "simplified sectionalizer" support (QSTS studies), as well as the updated current-checking functionality of feature/990. The basic function of the sectionalizer is to provide fault/section isolation capabilities, typically in conjunction with a recloser object and the reliability module.
General Requirements
The updated sectionalizer is meant manipulate switch objects to open a section of a system when the proper fault current was registered through the device.
The final implementation of the sectionalizer will meet these requirements:
R1
The sectionalizer will be interface with a switch object.
R1.1
Sectionalizer will require a switch object as a parent
R1.2
Sectionalizer open/close actions will be sent to the switch object, which will perform the action
R1.3
Sectionalizer will use base link class connections to obtain current (Amps) values for actions
R2
The sectionalizer will support two modes of operation
R2.1
The sectionalizer 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 require reliability, and related link-based functions, to open the sectionalizer
R2.1.3
Traditional mode will behave like "pre-fault" and "post-fault" existing analysis - the transient portion will not be modeled.
R2.1.4
No fault current sensing or acting will occur in traditional mode. Any fault current calculations are informational only.
R2.2
The sectionalizer will support a local/individual-based mode of operation
R2.2.1
The sectionalizer will use local information to determine if it should open or close.
R2.2.1.1
The sectionalizer will monitor current passing through it and determine if it is above the define protection threshold.
R2.2.1.2
The sectionalizer will monitor the duration of exceeded current and determine if an action is needed
R2.2.2
The sectionalizer is assumed to not have fault-current-breaking capabilities
R2.2.2.1
Once an open is required, the sectionalizer will only perform the open action once the current flowing through it has dropped to zero.
R2.2.2.2
The sectionalizer will need to be deployed with another device or control capability, such as a recloser elsewhere, to provide the fault-current-breaking.
R3
The sectionalizer will work in both QSTS mode and deltamode
R3.1
The sectionalizer will retain the same capabilities (traditional vs. local/individual) in both QSTS and deltamode simulation.
R3.2
The sectionalizer will not self-trigger deltamode, instead relying on another object to handle that transition.
R4
Upon opening for fault conditions, the sectionalizer will need to be manually closed via a player or external method