A self-excited push-pull converter

Abstract

The invention discloses a self-excited push-pull type converter which comprises a Royer circuit. An inductor connects a power supply terminal of the Royer circuit with a center tap of a transformer primary winding in the Royer circuit. An inductance value of the inductor is less than one-tenth of an inductance value of a primary winding in the transformer. The center tap of the primary winding isa connection point of two primary windings of the transformer. The self-excited push-pull type converter of the present invention has the characteristics of high consistency, easy debugging, low technology requirement, and good short circuit protection performance.

Description

technical field [0001] The invention relates to a self-excited push-pull converter, in particular to a self-excited push-pull converter in DC-DC or DC-AC in industrial control and lighting industries. Background technique [0002] The existing self-excited push-pull converter, the circuit structure comes from the self-excited oscillation push-pull triode single-transformer DC converter invented by G.H.Royer in 1955, which is also the beginning of realizing high-frequency conversion control circuit; some circuits From the self-excited push-pull double-transformer circuit invented by Jen Sen in the United States in 1957, it was later called the self-oscillating Jensen circuit; these two circuits are collectively referred to as the self-excited push-pull circuit pull converter. Compared with the self-oscillating Jensen circuit, the Royer circuit has an advantage. When the output load of the Royer circuit is short-circuited, the circuit design can realize the short-circuit prot...

AI Technical Summary

Problems solved by technology

[0012] 2. The efficiency and short-circuit protection performance of the existing Royer self-excited push-pull converter are not well balanced

That is, the efficiency and short-circuit protection performance of the existing Royer self-excited push-pull converter are contradictory. During the design, it often occurs that: the short-circuit protection performance is good, and the conversion efficiency is low; poor protection

[0014] 3. For the Royer self-excited push-pull converter circuit (such as image 3 ), the existing technology cannot achieve a good output short-circuit protection function. Basically, when the load is short-circuited, due to the existence of the damping inductance L1, the circuit cannot work at a relatively high frequency, and the first triode will be burned in a short period of time. TR1 and the second transistor TR2

[0015] 4. When the load is short-circuited, the existing Royer self-excited push-pull converter consumes a lot of power, and the short-circuit time is slightly longer, ranging from a few minutes to half an hour, and the circuit is easily damaged due to heat.

Images