Single Phase Transformers

Single - phase transformers, as the "adaptation expert" at the end of the power system, are designed for single - phase alternating current. They have a simple structure, focus on voltage adaptation in low - power and single - phase scenarios, and serve as a "terminal supplement" to the power system. Structurally, they consist of a single - phase iron core (double - column type / shell type) and a set of primary and secondary coils (multiple secondary sides can output multiple voltages). Small - capacity ones are mostly dry - type (such as ring - shaped and EI - type) and only equipped with basic overload protection like temperature fuses. In terms of performance, they have a small rated capacity (from several VA to several hundred kVA). Small - capacity ones have relatively low efficiency (80% - 90%) and high cost per unit capacity, but there is no three - phase balance problem and they are flexible in adaptation. Their core applications include low - voltage conversion (220V→12V/5V) for household appliances (air conditioners, refrigerators) and electronic devices (power adapters), as well as voltage adaptation for imported equipment (110V appliances), power supply for single - phase lighting (street lamps), and small single - phase industrial equipment (electric welding machines).