ISLAND_DETECT
Passive islanding detection combining ROCOF, vector shift and a voltage/frequency window.
When to use it
Use ISLAND_DETECT when a microgrid or DER site needs a supervisory answer to whether the utility source is still present, from PCC voltage, frequency and phase-angle measurements it already has, alongside (not instead of) the active anti-islanding running inside the inverters.
Interface
The published port signature. This is the whole of what the block exposes to your program — the implementation body is not shown here and ships with the download.
Inputs
| Port | Type | Unit |
|---|---|---|
| ENABLE | BOOL | — |
| FREQ | REAL | Hz |
| ANG | REAL | deg |
| V_PU | REAL | pu |
| MEAS_OK | BOOL | — |
| F_NOM | REAL | Hz |
| DFDT_LIM | REAL | Hz/s |
| SHIFT_DEG | REAL | deg |
| V_LO_PU | REAL | pu |
| V_HI_PU | REAL | pu |
| F_LO_HZ | REAL | Hz |
| F_HI_HZ | REAL | Hz |
| FILT_S | REAL | s |
| CONFIRM_T | TIME | — |
| GRID_OK_T | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| ISLANDED | BOOL | — |
| GRID_OK | BOOL | — |
| METHOD | USINT | — |
| DETECT | BOOL | — |
| DFDT | REAL | Hz/s |
| ANG_SHIFT | REAL | deg |
| VALID | BOOL | — |
| ALM_MEAS_FAULT | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 10
- Simulated scans
- 166
- Simulator
- v0.1.0
Complete IEC 61131-3 implementation with a published test suite that runs on the vplant simulator. The counts above are that suite, executed on this build.
- Conforms to IEC 61131-3
- Conforms to IEC 61499
Download ISLAND_DETECT — free
Create a free Ri Tech account to download the block. You get the Structured Text body, the Rockwell Add-On Instruction (.L5X), the Schneider Control Expert DFB (.XDB), PLCopen XML, the IEC 61499 function block type (.fbt) and the datasheet.
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Source is never published on this page. The implementation is released to a signed-in Ri Tech account — free of charge, but never anonymously.