Confused about analog EMC design

[rohscomplaint]

Hi everyone,

I am now dealing with a high voltage inverter design. The IGBT switches controlled by CPU in 18KHz, that means that the several kilo volts voltage changes rapidly which result in my analog circuit can not work in a expected way because of noise.

I know maybe I can shield the analog circuit. However, faced with this kind of problem, I do not have so many ideas. I try to find some books and tutorials focus on this subject. But almost all EMC books and tutorials I can find are relative to digital circuit design but not analog.

Could anyone recommend some books or tutorials I am looking for?

Thanks in advance.

 

[jiripolivka]

Use a shielded enclosure made of aluminum sheet and use capacitor feedthroughs for all passing lines. The problem will be the HV output which is difficult to filter.
Like on the CRT TV sets, the HV block was enclosed in a perforated box, and to filter the HV output, CRT anode to external shield was used as a capacitor.

 

[franciscorc]

Hi all

There are two ways the interference can reach your circuit.Through the air or power line.
In the first case use the shielded enclosure and in the second use a line filter in the primary side of the inverter.

I don´t know details of your project but you can try dithering or sweeping using a spread-spectrum oscillator. A good example is Dallas DS1090
you can find further informations at **broken link removed**

Best

Francisco