Overview
The “Startup overcurrent protection” function protects Gas-turbine generators that can be started by static‑frequency converters (SFC) at low frequencies during the startup, Pumped-storage generators or motors that meet two special conditions, and Hydraulic power plant that is in the electric-braking mode.
For more detailed information on “Startup overcurrent protection” function, refer to SIPROTEC 5 devices, V8.30 & higher manuals.
To see other supported functions, click here.
Structure/Embedding of the Function
Setting Parameters
Setting parameters for Startup overcurrent protection
| Addr. | Parameter | C | Setting Options | Default Setting |
| Stage 1 | ||||
| _:17551:1 | Stage 1:Mode | off on test |
off | |
| _:17551:2 | Stage 1:Operate & flt.rec. blocked | no yes |
no | |
| _:17551:3 | Stage 1:Threshold | 1 A @ 100 Irated | 0.100 A to 35.000 A | 1.300 A |
| 5 A @ 100 Irated | 0.50 A to 175.00 A | 6.50 A | ||
| 1 A @ 50 Irated | 0.100 A to 35.000 A | 1.300 A | ||
| 5 A @ 50 Irated | 0.50 A to 175.00 A | 6.50 A | ||
| 1 A @ 1.6 Irated | 0.003 A to 1.600 A | 1.300 A | ||
| 5 A @ 1.6 Irated | 0.017 A to 8.000 A | 6.500 A | ||
| _:17551:7 | Stage 1:Dropout delay | 0.00 s to 60.00 s | 0.00 s | |
| _:17551:6 | Stage 1:Operate delay | 0.00 s to 60.00 s | 0.50 s | |
Logic Diagrams & highlights
Characteristic Quantities During Startup of a Gas Turbine
Operating Range and Possible Pickup Threshold of Short-Circuit Protection Functions
Logic Diagram of the General Functionality
Logic Diagram of the Startup Overcurrent Protection Stage
Short-Circuit Currents in the Generator During Startup (Srated, Gen = 300 MVA, Vrated, Gen = 15.75 kV, and frated = 50 Hz)
