Twowinding

Two-winding transformers, also known as twowinding transformers, are electrical devices that contain two separate windings—the primary and the secondary—on a common magnetic core. The windings are electrically isolated from each other, and energy is transferred by magnetic coupling rather than direct conduction.

When alternating current is applied to the primary winding, it generates a changing magnetic flux in the core. This flux links both windings and induces a voltage in the secondary winding. The relationship between the input and output voltages is determined by the turns ratio Np/Ns, so Vs = Vp × Ns/Np under ideal conditions. Current in the secondary induces a proportional flux in the core, and the transformer meets power balance within design limits.

Two-winding transformers can function as step-up or step-down devices, and they are common for impedance matching and galvanic isolation. They differ from autotransformers, which use a single winding with taps and provide smaller size and cost but lack full isolation.

Construction typically involves laminated iron or ferrite cores, insulated windings, and protective enclosures. The windings may be designed for high voltage, high current, or specialized frequencies. Real transformers exhibit losses due to resistance, core hysteresis, stray capacitances, and leakage inductance, so efficiency and voltage regulation depend on load and frequency.

Applications include power distribution, power supplies for electronics, isolation for measurement equipment, and audio or instrumentation contexts. While multi-winding transformers (with three or more windings) exist, the two-winding configuration remains a fundamental and widely used arrangement for voltage transformation with galvanic isolation.