Hi Prof. Can you suggest best random noise generator? It is very good to design jamming transmitter. I thought maybe one low biased diode in reverse to make a random source generator. Any idea??
Dear Sam, I had to use a copper shield between the primary and secondary to aviod EMI and partial discharge in a high voltage transformer, and I got a eddy current on the shield. How can I cope with this eddy current?
1. Make sure the copper is not acting as a short winding (closed loop) 2. Use as thin as possible copper sheet, like a tape. 3 rather than a sheet, use a winding layer as a shield with thin wire, one end open of course.
@@sambenyaakov How can I avoid partial discharge in a dc-dc transformer? I have potted the transformer and still some air is trapped inside the transformer causing ionization and partial discharge. Potting in the vacuum is not economical. Do you have any advice dear Sam?
Technically that's not an inverter, but ESC. Because I'm pretty sure due to efficiency demands, motors are connected to a battery "directly" via ESC after a BMS. Inverter is rather makes a stable voltage for different abstract consumers. SMPSes radiates more due to improper current path through PCB "antennas", rather than a pulsating current in wires (they have pretty big inductance). Thus even 3-stage EMI filters won't help if let's say a radio module catches this radiation emitted with the ESC "antennas".
Thank you for the interest, I am sorry but technically speaking you are mistaken. 1. Inverter is a unit that convert DC to AC. In an electrical vehicle this will normally be a three phase inverter. See www.nxp.com/applications/automotive/electrification-and-powertrain/electric-vehicle-ev-traction-inverter:EV-POWER-INVERTER#:~:text=The%20NXP%20EV%20traction%20inverter,high%20temperatures%20and%20be%20lightweight. 2. The battery is not connected to the inverter via a BMS. The BMS is in parallel to the battery while in may operate a contactor between the battery and the inverter. 3. The conducted EMI is measured on the cable between the inverter and battery, has nothing to do with the PCB. 4. The radiation EMI from the PCM is normally shielded by the housing and in any event negligible compared to the radiated EMI from the cables. Notice the long cables requires by the standard when testing for CSPR25. (slide 12 of video). 5. Filters ARE used to attenuate conducted EMI and shields to attenuate the radiated EMI. 6. And for your information: due to the high cost and size of the conducted EMI filters (which you can buy) manufacturers sometime forgo the testing of conducted and test only for radiated EMI of the inverter. This is possible since for the authorities, the approval is on the car and not on the components, and since the conducted EMI is just within the car it not relevant for passing the norm (although it may interfere internally).
I guess the high EMI caused the cars that crashed at 5:25 to be exactly the same model, but in different colors. Maybe their is some form of strong attraction between identical car models due to high EMI and this also caused them to crash at the same angle in the center of the street. But what are those things flying overhead?
😂😂AS for the flying objects, I think this is a hint by ChatGPT that EMI can be beneficial, jamming the communication of missiles and thereby causing them to explode, ha, ha!
Calling the ferrite "like a bagel" ... LOL never thought of a ferrite like a bagel. :) :)
batchen.cooking/recipe/%d7%91%d7%99%d7%99%d7%92%d7%9c%d7%a1-%d7%a2%d7%9d-%d7%a9%d7%95%d7%9e%d7%a9%d7%95%d7%9d-%d7%9c%d7%9c%d7%90-%d7%94%d7%aa%d7%a4%d7%97%d7%94/
Can I put a bit of butter on my ferrite ? 😀
@@k7iq 🥯ruclips.net/user/sgaming/emoji/7ff574f2/emoji_u1f96f.png
Sir could you make video on primary side control and secondary side control for isolated converter
To find videos in my channel: in search window of RUclips, type
sam ben yaakov x
E.g.
sam ben yaakov primary
Hi Prof.
Can you suggest best random noise generator?
It is very good to design jamming transmitter.
I thought maybe one low biased diode in reverse to make a random source generator.
Any idea??
A Zener diode is considered a good source of noise. Needs amplification of course.
Hhhg
Zener diode is considered a good noise source. You need amplification of course.
Dear Sam, I had to use a copper shield between the primary and secondary to aviod EMI and partial discharge in a high voltage transformer, and I got a eddy current on the shield. How can I cope with this eddy current?
1. Make sure the copper is not acting as a short winding (closed loop)
2. Use as thin as possible copper sheet, like a tape.
3 rather than a sheet, use a winding layer as a shield with thin wire, one end open of course.
@@sambenyaakov How can I avoid partial discharge in a dc-dc transformer? I have potted the transformer and still some air is trapped inside the transformer causing ionization and partial discharge. Potting in the vacuum is not economical. Do you have any advice dear Sam?
@@sambenyaakov thanks for the advice 🙏🙏🙏
@@Life64644 Try using a low viscosity potting material. Use vibrations to get rid of trapped air
Thanks. Can you do a video explaining common-mode and differential mode in a simple way? 🎉
Have you seen ruclips.net/video/5NRiLOvmXdA/видео.html ?
@@sambenyaakov No it seems not, thank you soooo much Professor! You are the best!
Thank you.
👍🙏
👍❤️🙏
🙏😊👍
Technically that's not an inverter, but ESC. Because I'm pretty sure due to efficiency demands, motors are connected to a battery "directly" via ESC after a BMS. Inverter is rather makes a stable voltage for different abstract consumers. SMPSes radiates more due to improper current path through PCB "antennas", rather than a pulsating current in wires (they have pretty big inductance). Thus even 3-stage EMI filters won't help if let's say a radio module catches this radiation emitted with the ESC "antennas".
Thank you for the interest, I am sorry but technically speaking you are mistaken.
1. Inverter is a unit that convert DC to AC. In an electrical vehicle this will normally be a three phase inverter. See www.nxp.com/applications/automotive/electrification-and-powertrain/electric-vehicle-ev-traction-inverter:EV-POWER-INVERTER#:~:text=The%20NXP%20EV%20traction%20inverter,high%20temperatures%20and%20be%20lightweight.
2. The battery is not connected to the inverter via a BMS. The BMS is in parallel to the battery while in may operate a contactor between the battery and the inverter.
3. The conducted EMI is measured on the cable between the inverter and battery, has nothing to do with the PCB.
4. The radiation EMI from the PCM is normally shielded by the housing and in any event negligible compared to the radiated EMI from the cables. Notice the long cables requires by the standard when testing for CSPR25. (slide 12 of video).
5. Filters ARE used to attenuate conducted EMI and shields to attenuate the radiated EMI.
6. And for your information: due to the high cost and size of the conducted EMI filters (which you can buy) manufacturers sometime forgo the testing of conducted and test only for radiated EMI of the inverter. This is possible since for the authorities, the approval is on the car and not on the components, and since the conducted EMI is just within the car it not relevant for passing the norm (although it may interfere internally).
I guess the high EMI caused the cars that crashed at 5:25 to be exactly the same model, but in different colors. Maybe their is some form of strong attraction between identical car models due to high EMI and this also caused them to crash at the same angle in the center of the street. But what are those things flying overhead?
😂😂AS for the flying objects, I think this is a hint by ChatGPT that EMI can be beneficial, jamming the communication of missiles and thereby causing them to explode, ha, ha!
Sir could you please make video on redundant power supply and change over circuit...
Have you seen ruclips.net/video/KS8U6C-mJvk/видео.html ?