About "Coupled SEPIC"

PowerAnts

About "Coupled SEPIC" [Copy link]

The coupling capacitor can be either very small or very large, small enough to only provide clamping for the main switch, or large enough that the voltage at its end is "almost unchanged";

The degree of inductive coupling can either have extremely small leakage inductance or be very large, almost as large as the self-inductance.

The leakage inductance of a toroidal double-wire winding is not actually so small that it cannot be ignored, and it is difficult to reduce it to less than 2%.

In addition, the working principles of the coupled and uncoupled second inductors are completely different, so the "coupled SEPIC" circuit only looks similar to the SEPIC. From a biological point of view, the two are at most of the same genus but different species.

PowerAnts

If we regard it as a flyback clamped by a coupled capacitor and an output diode, we can use a small capacitor to break the iron rule that the turns ratio of the "coupled SEPIC" must be 1, and freely play with the transformation ratio! ! !

maychang

"The leakage inductance of a toroidal core with two parallel wires is not actually small enough to be ignored, and it is difficult to reduce it to less than 2%."

If the two wires of the bifilar winding are twisted together and then wound around the magnetic ring, can the leakage inductance be lower?

PowerAnts

[quote]maychang posted on 2019-10-13 19:52 "The leakage inductance of the ring-core double-wire winding is not necessarily small enough to be ignored, and it is difficult to be less than 2%." If the double-wire winding is a twisted pair, it will be much better. I don't know if there is such an application. I will try the feasibility and cost-effectiveness of mass production if I have a chance (I have projects and cooperation resources)

PowerAnts

maychang posted on 2019-10-13 19:52 "The leakage inductance of a toroidal core bifilar winding is not necessarily small enough to be ignored, and it is difficult to reduce it to less than 2%." If the bifilar winding...

This is an inductor made of three 1mm diameter enameled wires. The gap between the outer wires is very large. If two windings are wound with twisted pair wires, the utilization rate of the inner wire will decrease. Does Mr. Zhang have any good ideas?

maychang

PowerAnts posted on 2019-10-14 09:18 maychang posted on 2019-10-13 19:52 “The leakage inductance of the toroidal core double-wire parallel winding is not necessarily so small that it cannot be ignored. It is difficult to reduce it to less than 2%...

There is no silver bullet.

I think: unless the inner circle is folded up and wound around, the window area utilization rate cannot be improved.

PowerAnts

maychang posted on 2019-10-14 10:43 There is no magic trick. I think: unless the inner circle is stacked up, the window area utilization rate cannot be improved.

The calculation of working hours before mass production of inductors is for reference!

70a26c190fad2162828c405cf60ba4af.mp4 (1.39 MB, downloads: 129)

2019-10-14 11:40 上传

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maychang

PowerAnts posted on 2019-10-14 11:42 The calculation of working hours before mass production of inductors is for reference! Nylon hook needles are used

If we have to consider the working hours when we go around the loop, I have no idea.

不亦心

PowerAnts posted on 2019-10-14 11:42 The calculation of working hours before mass production of inductors is for reference! Nylon hook needles are used

This video is so exaggerated...

The labor cost saved by changing the machine operation on the Leeds line can make up for the price difference of wire materials.

PowerAnts

Bu Yixin posted on 2019-10-14 23:03 This video is so exaggerated. . . If the Leeds line is changed to machine operation, the labor cost saved can make up for the price difference of wire materials.

Each time I place an order for more than 20 models, each model costs several K. The ring winding machine has not been programmed yet, and the manual winding machine has finished winding.

tg205205

PowerAnts posted on 2019-10-14 11:42 The calculation of working hours before mass production of inductors is for reference! Nylon hook needles are used

This video is so exaggerated. At this speed, the workers on the production line must be exhausted.