Making a tranformer

[RobertEagle]

Hi,

I want to make a transformer. These are the properties of the transformer I want:

• have high frequencies (eg. 10-25Khz, high saturation level)
• have high voltage limit (up to 1Kv)
• have a ratio between primary and secondary of 100:1

I've already got a ferrite core, E shape. I've already made the coils, with a ratio of 100. The problem is when I turn it on. On the oscilloscope it looks like it's oversaturated. I barely get a few mW out of 2W.
I've used the ferrite because I know it can handle frequencies up to 1Mhz.
The source signal has a frequency of 20Khz, at 900V, when it's not connected to the transformer.

What's the problem here? Should I use a different kind of core?

Thank you

 

[Harald Kapp]

Here's a tutorial on transformer design.
A shot from the hip: 20kHz is still too low a frequency to keep the core from saturating. On the other hand, 20kHz is a bit on the high side for a conventional metal core. You can either use a bigger core or a higher frequency (if you can).

You may try this software (free demo available)