Recloser
A recloser is a self-controlled device for automatically interrupting and reclosing an AC circuit, with a predetermined sequence of opening and reclosing. Like a circuit breaker, a recloser can be used for
interrupting currents. The interrupting medium of a recloser is most commonly vacuum or oil. The recloser control can be electronic, electromechanical or hydraulic. A hydraulic recloser uses springs and hydraulic
systems for timing and actuation. In short, a recloser is a circuit breaker which is integrated with a relay and a reclosing control element.
Automatic reclosing is motivated by the fact that about 60-80% of all overhead distribution faults are temporary and last only a few cycles or a few seconds. For example, a branch may blow against a circuit and then fall to the ground. As a result, it becomes very attractive to reclose following an initial opening of the protection device.
Reclosers have many distribution applications:
• It can be used in the substation as feeder interrupters instead of circuit breakers. Reclosers are used more in smaller stations and circuit breakers more in larger stations.
• Three-phase reclosers can be used on the main feeder to provide necessary protection coverage on longer circuits, along with improved reliability.
• Reclosers are available as single-phase units, so they can be used on single-phase taps (laterals) instead of fuses.
• Another common application is in auto-loop automation schemes to automatically sectionalize customers after a fault.
• Three-phase reclosers are available that can operate each phase independently (so a single-phase fault will only open one phase)
The properties of the recloser object included in OpenDSS are as follows:
Property |
Description |
(1) MonitoredObj |
Full object name of the circuit element, typically a line, transformer, load, or generator, to which the Recloser's PT and/or CT are connected. This is the "monitored" element. There is no default; must be specified. |
(2) MonitoredTerm |
Number of the terminal of the circuit element to which the Recloser is connected. 1 or 2, typically. Default is 1. |
(3) SwitchedObj |
Name of circuit element switch that the Recloser controls. Specify the full object name.Defaults to the same as the Monitored element. This is the "controlled" element. |
(4) SwitchedTerm |
Number of the terminal of the controlled element in which the switch is controlled by the Recloser. 1 or 2, typically. Default is 1. |
(5) NumFast |
Number of Fast (fuse saving) operations. Default is 1. (See "Shots") |
(6) PhaseFast |
Name of the TCC Curve object that determines the Phase Fast trip. Must have been previously defined as a TCC_Curve object. Default is "A". Multiplying the current values in the curve by the "phasetrip" value gives the actual current. |
(7) PhaseDelayed |
Name of the TCC Curve object that determines the Phase Delayed trip. Must have been previously defined as a TCC_Curve object. Default is "D".Multiplying the current values in the curve by the "phasetrip" value gives the actual current. |
(8) GroundFast |
Name of the TCC Curve object that determines the Ground Fast trip. Must have been previously defined as a TCC_Curve object. Default is none (ignored). Multiplying the current values in the curve by the "groundtrip" value gives the actual current. |
(9) GroundDelayed |
Name of the TCC Curve object that determines the Ground Delayed trip. Must have been previously defined as a TCC_Curve object. Default is none (ignored).Multiplying the current values in the curve by the "groundtrip" value gives the actual current. |
(10) PhaseTrip |
Multiplier or actual phase amps for the phase TCC curve. Defaults to 1.0. |
(11) GroundTrip |
Multiplier or actual ground amps (3I0) for the ground TCC curve. Defaults to 1.0. |
(12) PhaseInst |
Actual amps for instantaneous phase trip which is assumed to happen in 0.01 sec + Delay Time. Default is 0.0, which signifies no inst trip. |
(13) GroundInst |
Actual amps for instantaneous ground trip which is assumed to happen in 0.01 sec + Delay Time.Default is 0.0, which signifies no inst trip. |
(14) Reset |
Reset time in sec for Recloser. Default is 15. |
(15) Shots |
Total Number of fast and delayed shots to lockout. Default is 4. This is one more than the number of reclose intervals. |
(16) RecloseIntervals |
Array of reclose intervals. Default for Recloser is (0.5, 2.0, 2.0) seconds. A locked out Recloser must be closed manually (action=close). |
(17) Delay |
Fixed delay time (sec) added to Recloser trip time. Default is 0.0. Used to represent breaker time or any other delay. |
(18) Action |
{Trip/Open | Close} Action that overrides the Recloser control. Simulates manual control on recloser "Trip" or "Open" causes the controlled element to open and lock out. "Close" causes the controlled element to close and the Recloser to reset to its first operation. |
(19) TDPhFast |
Time dial for Phase Fast trip curve. Multiplier on time axis of specified curve. Default=1.0. |
(20) TDGrFast |
Time dial for Ground Fast trip curve. Multiplier on time axis of specified curve. Default=1.0. |
(21) TDPhDelayed |
Time dial for Phase Delayed trip curve. Multiplier on time axis of specified curve. Default=1.0. |
(22) TDGrDelayed |
Time dial for Ground Delayed trip curve. Multiplier on time axis of specified curve. Default=1.0. |
(23) basefreq |
Base Frequency for ratings. |
(24) enabled |
{Yes|No or True|False} Indicates whether this element is enabled. |
(25) like |
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