Design requirements and inductance of high frequency output transformer

- Feb 27, 2019-

In the design process of the high-frequency output transformer, the leakage inductance and distributed capacitance of the transformer must be minimized, because the high-frequency transformer in the switching power supply transmits a high-frequency pulse square wave signal. During transmission transients, leakage inductance and distributed capacitance can cause inrush currents and spikes, as well as top oscillations, resulting in increased losses. Usually, the leakage inductance of the transformer is controlled to be 1% to 3% of the primary inductance.

1. Leakage inductance of the primary coil: The leakage inductance of the transformer is directly caused by the fact that the magnetic flux between the turns and the turns is not fully coupled between the primary and secondary coils during operation.

2. Distributed capacitance: between the windings of the transformer windings, between the upper and lower layers of the same winding, between the different windings, the capacitance formed between the winding and the shielding layer is called the distributed capacitance.www.ctsensorducer.com