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I am developing a PCB project but i want to use the PCB in noisy environments (which usually contains 7.5-45 kW multiple motors with frequency inverters and also ignition transformers). I made some basic test and test circuits passed them but I want to create a really noisy environment in order to test my PCB under conditions which are more noisy than the real environment. How can i generate this noisy environment?

I thought that some big coil with a high frequency square wave (square wave because frequency domain of it contains more harmonics (am I right?)) generator can produce instantly changing magnetic field and it can induce voltage drop between my traces. But I couldn't be sure that it is enough.

Actually, I want to learn what is noise and what types of noise there are. And I want to test my PCB's vulnerability to noisy environments by learning step by step EM theory. I also want to learn mathematics beyond this but my first purpose creating a noisy environment (whatever it means, i don't really know) and then understand how these things work.

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  • \$\begingroup\$ There are standards for this. Check out MIL-STD-462 and MIL-STD-461 \$\endgroup\$
    – Aaron
    Commented Sep 12, 2019 at 20:20
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    \$\begingroup\$ The book Electromagnetic Compatibility Engineering book is written to teach you exactly everything there is to know about this. \$\endgroup\$
    – pipe
    Commented Sep 12, 2019 at 20:43
  • \$\begingroup\$ bring a kitchen-mixer near. One of those mixers with lots of sparks from the motors. \$\endgroup\$
    – analogsystemsrf
    Commented Sep 13, 2019 at 1:56

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If you can't afford a full-size EMC chamber you could consider a TEM cell (and maybe an EMC "bag").

It is basically a piece of waveguide that you can put small things in. It works both for measuring the emissions from your PCB (when connected to a spectrum analyzer) and for testing immunity (you connect an RF amplifier on one end and a dummy load on the other).

It looks like this: https://www.telonic.co.uk/Tekbox-TBTC2-TEM-Cell-p/tbtc2.htm https://www.emcfastpass.com/test-equipment/shop/gtem-tem-cells/compact-tem-cell-tbtc1/

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  • \$\begingroup\$ yes. If you determine the most sensitive node in the circuit you can inject noise into it with a transformer and monitor the output response. Spectrum Analyzers are purpose built for this, they sweep through the entire frequency range and read the output response at each point. \$\endgroup\$
    – Tony
    Commented Sep 13, 2019 at 0:31

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