Transformer for switching power supply of video intercom system and preparation method thereof

Abstract

The invention discloses and provides a transformer for a switching power supply of a video intercom system with simple structure, low production cost and relatively low leakage inductance without reducing power supply efficiency and a preparation method thereof. The method is to add a shielding layer during the winding process, firstly wind the primary winding and auxiliary primary winding, and then reversely wind the secondary winding. The transformer for the switching power supply of the video intercom system includes a skeleton, a magnetic core, a coil winding and a copper foil shielding layer. The coil winding includes a primary winding, an auxiliary primary winding and a secondary winding, and the copper foil shielding layer includes The first copper foil shielding layer and the second copper foil shielding layer, the auxiliary primary windings are all forward wound, the secondary windings are reverse wound, and the bonding layer of the primary winding and the auxiliary primary winding is The bonding layer of the secondary winding is the terminal with the same name, the first copper foil shielding layer is connected to the ground of the primary winding, and the second copper foil shielding layer is connected to the ground of the secondary winding.

Description

technical field [0001] The invention relates to a transformer for a switching power supply of a video intercom system and a preparation method thereof. Background technique [0002] With the rapid development of power electronics technology, the relationship between electronic equipment and people's work and life is increasingly close, and electronic equipment is inseparable from a reliable power supply. In the 1980s, computer power supplies fully realized switching power supplies, and took the lead in completing computer power supplies. In the 1990s, switching power supplies entered various electronic and electrical equipment fields one after another. Switching power supplies have been widely used in program-controlled switches, communications, electronic testing equipment power supplies, and control equipment power supplies, which has promoted the rapid development of switching power supply technology. . In recent years, switching power supply has been widely used. Switch...

AI Technical Summary

Problems solved by technology

In recent years, switching power supply has been widely used. Switching power supply is also used in the second-line system of security intercom system. It generally adopts the power supply mode of series regulated power supply. In the actual working process, with the increase of switching frequency , the electromagnetic environment of the switching power supply is becoming more and more complex, and the corresponding electromagnetic interference is more and more seriously affecting the normal operation of the switching power supply itself and its surrounding electronic equipment

The leakage inductance of the high-frequency transformer is one of its main sources of electromagnetic interference. This is because when the switching tube in the switching power supply is turned off quickly, an induced potential is generated on the leakage inductance of the transformer. This induced potential is superimposed on the closing of the transformer winding. The peak turn-off voltage is generated on the cut-off voltage. The peak turn-off voltage causes electromagnetic interference and produces a large voltage stress on the switch tube, which will not only cause noise in the audio signal and snowflakes in the video signal, but may also damage the switch tube. And increase the switching loss, so it is very necessary to reduce the leakage inductance of the transformer. In order to effectively reduce the leakage inductance of the transformer, most of the methods are to increase the inductance in the circuit to block the clutter, which will reduce the efficiency of the switching power supply. Cause product volume to increase and the increase of production cost, this just exists certain inconvenience

Images