Flybackprincip

Flybackprincip, also known as the flyback transformer or switching transformer, is a type of transformer commonly used in switched-mode power supplies (SMPS). It differs from conventional transformers in that it stores energy in a magnetic field during one part of the switching cycle and then releases that energy during another part. This intermittent operation allows for efficient voltage conversion in a compact design.

The core of a flyback transformer is typically made of ferrite and is not continuously driven into saturation. Instead, it is magnetized and demagnetized with each switching cycle. This energy storage mechanism is crucial to its operation. The primary winding is connected to the input voltage source through a switching element, usually a MOSFET. When the switch is on, current flows through the primary winding, building up magnetic flux in the core and storing energy.

When the switch turns off, the magnetic field collapses. This rapid change in flux induces a voltage in the secondary winding. Because the primary circuit is interrupted, the energy stored in the core is transferred to the secondary circuit, often through a diode. The output voltage is regulated by controlling the duty cycle of the switching element. This makes the flyback topology suitable for applications requiring isolation and voltage step-up or step-down conversion.

Flyback converters are often used in low-power applications such as battery chargers, LED drivers, and small consumer electronics due to their simplicity and cost-effectiveness. Their ability to provide multiple isolated outputs from a single transformer also contributes to their popularity in certain designs.