What are advantages and disadvantages each for delta and Y power system?

Question

What are the advantages and disadvantages each for a delta power system and a grounded Y power system? I am referring this as a high voltage distribution system (2.2kv to 69kv).

Answer 1

Wye systems obviously have a convenient point to connect to ground. It is generally not the wye or delta system per se, power systems that have delta primaries on the transformers with wye secondaries do not pass ground fault currents through the transformer. Therefore, a power system that was established in this way has better, more sensitive protection, from ground faults. You only have to co-ordinate your ground fault protection back to the transformer.

You can also limit the ground fault current in a wye system with a resistor in the ground connection.

Answer 2

Grounding on a Y system is always at the source of the line so that any ground faults will operate a GF relay and open the breaker. Y grounded systems keep each leg at 120° to each other regardless of out of balance loads.
Delta systems are ungrounded and a short to ground will not necessarily trip the breaker. Unbalanced loads will cause a vector shift which can cause overheating in TXFMRS and motors and failures.

Answer 3

Sounds like an interested question

Answer 4

very good question