Which type of transformer provides a steady secondary voltage from no load to full load?

The type of transformer that provides a steady secondary voltage from no load to full load is a constant-potential transformer. This type is specifically designed to maintain a relatively constant output voltage regardless of the load variations. In applications where stable voltage is crucial, such as in medical equipment, constant-potential transformers ensure that devices receive a reliable power supply.

When a constant-potential transformer operates, it adjusts to load changes without significant fluctuations in voltage. This steady performance is important for sensitive devices that require consistent power to function correctly, as voltage variations can affect performance and potentially harm the equipment.

In contrast, other transformer types, such as current or constant-current transformers, have their own distinct functionalities and typically do not focus on providing a steady voltage under varying load conditions. Similarly, varying-potential transformers do not maintain a constant output voltage and can fluctuate with load. Therefore, the design and functionality of a constant-potential transformer make it the ideal choice for applications needing stable voltage output.