circuit provide 500 V DC pulse

[jatnc]

Hi friends!!

I'm not very good in designing circuits...I appreciate your help..Thanks in advance

Design two circuits (using source-able parts) that can provide the 500V pulse. The starting pulse should be initiated by a push button (But don’t put a push button in the 500V circuit). One circuit should be supplied by 120Vac, and the second supplied by 12Vdc. Provide schematics in both cases. (Note: The circuit needs to provide only minimal energy so current should be extremely low).

 

[jiripolivka]

You need first a DC source with 500 V output. For an "extremely low current" you can use a capacitor charged to 500 V.

From 120V AC, I would use a voltage tripler or a 120V/450V transformer and rectifier diodes rated to ~1 kV.

As "the push button" must not be in the 500 V circuit", you can use a relay to transfer the 500V from the charged capacitor to the load. You can also use a SCR or a thyristor for the purpose, or a HV MOSFET.

As there is no definition of the output pulse shape, no more details can be invented. Also the load must be well defined.

Please be aware that anything connected to 120V AC and generating 500V can be extremely dangerous; people can be killed by it.

I your teacher gave you such task, such person looks to me very uneducated; be careful of such wrong definitions.

 

[jatnc]

You need first a DC source with 500 V output. For an "extremely low current" you can use a capacitor charged to 500 V.

From 120V AC, I would use a voltage tripler or a 120V/450V transformer and rectifier diodes rated to ~1 kV.

As "the push button" must not be in the 500 V circuit", you can use a relay to transfer the 500V from the charged capacitor to the load. You can also use a SCR or a thyristor for the purpose, or a HV MOSFET.

As there is no definition of the output pulse shape, no more details can be invented. Also the load must be well defined.

Please be aware that anything connected to 120V AC and generating 500V can be extremely dangerous; people can be killed by it.

I your teacher gave you such task, such person looks to me very uneducated; be careful of such wrong definitions.

Thank you for your help. The 500 V Dc pulse is required ignition coil in order to ignite the gas inside of a flash lamp that is used to optically pump a alexandrite laser. Could you provide me the circuit diagram with the components, please?
Thanks in advance...

 

[jiripolivka]

Thank you for your help. The 500 V Dc pulse is required ignition coil in order to ignite the gas inside of a flash lamp that is used to optically pump a alexandrite laser. Could you provide me the circuit diagram with the components, please?
Thanks in advance...

I think 500 V pulse specification may not work. I used >3 kV to trigger a photo flash tube. The best advice is to try photoflash circuits used in single-use cheap cameras . They operate on 3 V DC.. If more voltage is needed, try to look on "www.allelectronics.com", they sell 12 VDC photoflash light circuits you can use. THe cost is ~$6 , easier than building your circuit.
If the repeat frequency should be higher than 1-2 Hz, use a car ignition coil driven from 12 VDC by a 2N3055 transistor or IRF 520 MOSFET.The driving pulse generator is a 555 IC. Lots of HV pulse circuits can be found on the Eda board forum. You can try also a low-cost electric fence pulse source.

 

[jatnc]

I think 500 V pulse specification may not work. I used >3 kV to trigger a photo flash tube. The best advice is to try photoflash circuits used in single-use cheap cameras . They operate on 3 V DC.. If more voltage is needed, try to look on "www.allelectronics.com", they sell 12 VDC photoflash light circuits you can use. THe cost is ~$6 , easier than building your circuit.
If the repeat frequency should be higher than 1-2 Hz, use a car ignition coil driven from 12 VDC by a 2N3055 transistor or IRF 520 MOSFET.The driving pulse generator is a 555 IC. Lots of HV pulse circuits can be found on the Eda board forum. You can try also a low-cost electric fence pulse source.

Again thank you for your explanation. It is an assignment that my professor gave me. I don't have much idea about electronic circuits very much. I spent a good time for this. I shall be grateful if anyone could help me to solve this..I need the circuit (2 of them) in order to finish this assignment...My professor gave me some hints what the circuit might look like..
Low voltage DC source-switcher/chopper/buckboost(don't know what is it)-transformer-rectifier stage-voltage multiplier-trigger pulse.

One question? Do we get DC pulses if we use a chopper which is fed by a constant DC source?

He also said about simmer power supply. Any idea what is it?

Thanks in advance

 

[jiripolivka]

I have built several similar circuits, mainly to fire the photoflash lamp with A rate of >10 Hz. I did it 35 years ago, so I have no schematics to offer. Please try the "www.allelectronics.com", they sell such kits for $6 or so, with a photoflash lamp included.
You can try if the circuit can fire your lamp. The trigger pulse transformer is the secret; you can make yours with a "longer" secondary if >3 kV is needed. This transformer must be located close to the triggered lamp, other components can be far from it.

A chopper interrupting a DC voltage does not generate "DC pulses" but rectangular ones. A "simmer" power supply means that it generates a much lower current than normal.

 

[jatnc]

I have built several similar circuits, mainly to fire the photoflash lamp with A rate of >10 Hz. I did it 35 years ago, so I have no schematics to offer. Please try the "www.allelectronics.com", they sell such kits for $6 or so, with a photoflash lamp included.
You can try if the circuit can fire your lamp. The trigger pulse transformer is the secret; you can make yours with a "longer" secondary if >3 kV is needed. This transformer must be located close to the triggered lamp, other components can be far from it.

A chopper interrupting a DC voltage does not generate "DC pulses" but rectangular ones. A "simmer" power supply means that it generates a much lower current than normal.

Hi again!!

Thank you very much for all your suggestion. I appreciate that...I will look into your suggestion.
May *** bless you!!
Bye