from the diagram you do not show where your drive signal for the hbridge driver is comming from. can u please review. from the diagram in post 2 you could see that the 556 was also fed back with the voltage from the first conversion. but from my understanding of the circuit in post 2 one of the first 555 is use as an astable and the other a monostable.
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load vltage dropping can also be caused by the size of the transformer which in your cas is the hf. if they are not properly sized.
The left side of the Hbridge is fed from a micro with 50hz. The right side of the bridge is fed with 28k8kHz PWM. 50Hz is used for timing, pwm for building the sine-wave. With the right two pole filter a true sine is created. thats working fine.
Can anyone help me with some hftransformer design software?
if u are using a micro to drive the gates as said then u make your programme run in a close loop such that you compensate for the drop in voltage in your software.
@babatundeawe
As you see in the schematics the sg3525 is selfadjusting. I think the core is collapsing like you said in a previous post.
Do you have hf-transformer design software? Like the online poweresim?
There is advertising element of content I cant publish that. I dont want to change and modify original content of author or project poster. If I remember there was priece per PCB, phone and email for ordering on PCB (if I remember corectly).
I always sharing all with others, but I cant post something and get infranction + deleting post.
In few threads also there was conversation about some projects from SiliconChip or Elektor, but this cannot be posted here with complete article text and material, but I always help others to get help on one or another way, but looking to stay in forum rules range.
i dont have any software for hf design but there is a web page that has a java applet. i will try and dig it up or u can google it. pls just give me some time.
@babatundeawe
Thank for the link. Its very helpful. I shall make my own calculations and check it with this site.
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The PushPull on the site from the link has only one primary coil. My design is one with a centre tap. Can this be used with the same applet?
Or should i change my design?
but what i will suggest is that you should calculate the total voltage that would measured from end - end of the xformer that is. if u are going to use a 12v - 0 -12v primary then use 24volts as your primary voltage then you divide the number of turns for the primary side by 2 then you will get you center tap.
Hi Mr_Rohrich,
Be carefull while using a center taped transformer for smps because a slightly different ratio in primary turns can damage the core burn the Fets. It is better to use Half bridge.
Regards ani