Limit the impact of the fault within the installation
In the event of a fault, the voltage of the installation is severely affected and risks causing a loss of loads. In particular the management of faults related to short circuits within a critical installation using static transfer systems (STS) is particularly important.
In order to guarantee the continuity of the supply to their load, the STS must:
- Operate autonomously
- Be able to detect and differentiate a short-circuit downstream or upstream
- Carry out a transfer of sources without overlap to avoid the propagation of the fault
- Ensure the islanding of a short-circuited load
In the event of a short-circuit downstream of an STS, it must isolate the fault to prevent its propagation and alert the operator. The other STS connected to the same source must protect their load by immediately transferring it to an alternative source without propagating the fault.
A short-circuit appears on a load supplied by source B and induces a voltage disturbance on the distribution of source B.
The local STS isolates the fault on source B by preventing its transfer. The other STS immediately transfer their load to source A without overlap.
The fault has been isolated on source B and the other loads are protected by source A.
A fault occurs upstream of an STS supplied by source B causing a voltage disturbance on the distribution of source B.
The STS immediately transfer their load to source A without overlap.
The fault has been isolated on source B and the other loads are protected by source A.
Socomec solution
STATYS static transfer systems
The STATYS range of static transfer systems (STS) incorporates in its design more than 30 years of experience and 4 generations of STS. The thousands of hours of operation and the many units installed have improved the detection and qualification of faults. It maximizes availability by guaranteeing transfer without overlap as well as fault isolation in the event of a downstream short-circuit.
