Better protection for a delta circuit
Better protection for a delta circuit
(OP)
We have a delta configured circuit, that is several miles long. It runs through a mountainous area, so conversion to a wye isen't much of an option.
The problem is to detect ground faults, currents are close to zero (There is a wye connected generation source that sometimes runs).
At issue is if we use neutral voltage detection, we may see more third harmonic under normal conditions, then we may see during a fault.
Any better ground protection ideas?
The problem is to detect ground faults, currents are close to zero (There is a wye connected generation source that sometimes runs).
At issue is if we use neutral voltage detection, we may see more third harmonic under normal conditions, then we may see during a fault.
Any better ground protection ideas?






RE: Better protection for a delta circuit
Rafiq Bulsara
http://www.srengineersct.com
RE: Better protection for a delta circuit
RE: Better protection for a delta circuit
We are considering a wye transformer, or a zig-zag, however we wanted to know what other options might be available.
RE: Better protection for a delta circuit
Is the design for a delta network related for continued production for a phase-groud type fault ?
A zero sequence voltage detector network can work in most instances for a single phase to ground type fault. Basically consist of a Y-D set of PT's with open corner secondary connected to an UV relay or a voltage operated type inverse-time relay. Can also be used for ground alarm functions.
Loading resistor on the secodary a necesity for the circuit to operate realiably.