Which three-phase transformer connection yields a displacement of 0 degrees by conventional means?

The Wye-Wye connection in a three-phase transformer configuration results in a phase displacement of 0 degrees. This means that the voltages in each phase are in alignment and not shifted in time relative to each other.

In a Wye-Wye connection, each phase is connected in a "Y" configuration, where each transformer's neutral point is typically grounded. This configuration is significant because it offers a balanced load and reduces the line-to-line voltage as distributed across the phases. Moreover, the absence of phase displacement ensures that the system operates efficiently with minimal phase shift, making it ideal for systems where synchronous operation of phases is critical.

The other configurations lead to various degrees of phase displacement, which can introduce complications such as harmonics or imbalances in systems. For example, a Delta-Delta connection causes a 30-degree displacement, while Wye-Delta and Delta-Wye connections create a 30-degree phase shift as well, thus impacting the overall performance of the system compared to a zero-degree shift in the Wye-Wye configuration.