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 | — |
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
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 and the datasheet.
Every block in the catalogue is free to download, in every format it ships, with no purchase and no card. Browsing needs no account at all; downloading needs a signed-in one, so the block lands in your library and re-downloads whenever you need it.
Source is never published on this page. The implementation is released to a signed-in Ri Tech account — free of charge, but never anonymously.