PRIMARY_FREQ_CTRL
Primary frequency control: governor-style droop with a settable deadband, response limit and actuator lag, for islanded operation.
When to use it
Use PRIMARY_FREQ_CTRL when a dispatchable unit — genset, CHP, grid-forming inverter — must share load with other units in an island by drooping its output against frequency, rather than holding a fixed setpoint.
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 |
| FREQ_OK | BOOL | — |
| F_NOM | REAL | Hz |
| DROOP_PCT | REAL | % |
| DEADBAND_HZ | REAL | Hz |
| P_RATED | REAL | kW |
| DP_MAX_PCT | REAL | % |
| TAU_S | REAL | s |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| DELTA_P | REAL | kW |
| DELTA_P_RAW | REAL | kW |
| ACTIVE | BOOL | — |
| AT_LIMIT | BOOL | — |
| VALID | BOOL | — |
| ALM_FREQ_FAULT | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Validation evidence
- Tests
- 9
- Simulated scans
- 355
- 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 PRIMARY_FREQ_CTRL — free
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