1khz 100v 500w power supply

Thread Starter

jaangalab

Joined Mar 28, 2010
12
hi frnds i want to make a power supply 1khz 100v 500w pls sugest me circuit ihave a circuit but it igbt due to cost i want to mate it from transiter if any body have circuit pls share me
thanks
 

beenthere

Joined Apr 20, 2004
15,819
Could you give some more information? Most power supplies are for DC power. The 1 KHz requirement is hard to understand. What is this power for?
 

SgtWookie

Joined Jul 17, 2007
22,230
Along with the information Beenthere asked for, what kind of input power do you plan to use?

Mains power at 120v/60Hz, 220V/50Hz, battery power?

If battery power, what battery type, output voltage and AH rating?
 

rogs

Joined Aug 28, 2009
279
I use what you describe all the time in my work, but I don't call it a power supply - I call it a 100 volt line audio power amplifier!
100 volt line is the common output for distributed public address systems, here in the UK. (I believe the US uses 70 volts).

Use a class 'D' audio amplifier, and a linear toroidal transformer, and you should get something like 85- 90% efficiency.
 

Thread Starter

jaangalab

Joined Mar 28, 2010
12
the circuit i want is used for strips mill my input is 415v 50hz i need constant current 100v 1khz 500w output is conect to a coil winding on a soft iron plate
 

JDT

Joined Feb 12, 2009
657
I assume this is for inductive heating? If it was resistive heating then the frequency would be unimportant.

I think the cheapest way will be to get a large audio amplifier. I have some that are 2 channel at 500W per channel (but you are not having them!) These are rack mounted "2U".These can be "bridge connected" with a switch on the back making them single 1000W. You would get more than 100V without a transformer.

Build a simple 1KHz sine wave oscillator. Feed this into the input. Monitor the current with a DVM on AC current range in series with the load. Increase gain SLOWLY from zero and see what happens!

Try ebay for the amplifier. Disco and professional audio section. Expect to pay £150 plus. Better quality amplifiers have better overload protection. Not worth building one.
 

rogs

Joined Aug 28, 2009
279
If cost is an issue, then as both JDT and I have suggested, a high power audio amplifier would probably be your best option. You are unlikely to be able to build one for less than you can buy one, but if you feel you can, just Google audio amplifier schematics -there are lots of them out there!
 

Thread Starter

jaangalab

Joined Mar 28, 2010
12
i get a 800w audio amp schematics from google can it solve my tention and i have to attach it 1khz how can i make it and how can i make feedbake cirent limit voltage limit in it pls sugest me
thanks
 

Attachments

rogs

Joined Aug 28, 2009
279
That circuit appears to be based on the original Hitachi circuit from the 1980's that was published as an application for their lateral mosfet output devices. It should work OK, but there are one or two points you need to be aware of:

1) You're going to need a fairly massive heatsink to be able to dissapate the heat generated by a class A-B audio amplifier, providing a continuous 500W output. You'll probably need to dissapate in the order of 400 to 500W of heat, on a continuous basis.
I would guess that will require a forced cooling (fan) arrangement of some sort.

2) Class A-B amplifiers are not efficient - typically 35-55%, depending on load conditions, so you are going to have to generate at least 1000W of DC power at +/-85V to supply an amplifier based on the circuit published.

This is going to cost you a lot more money, for a one off project, than simply buying a commercial class D amplifier of the required rating. Are you sure you really need to build your own, if it's more expensive?
 

Thread Starter

jaangalab

Joined Mar 28, 2010
12
i want to buld efficency is the mater i use water cooled heat seank i have these heat sink in lot i get them from a old things shop at the @ scrap
thanks
 

JDT

Joined Feb 12, 2009
657
Your circuit shows 2 amplifiers - bridge connected.

It does not show the power supply. You need to think about the cost of this.

For high efficiency you need a Class D amplifier. Can be built. Google for circuit diagrams. Not an easy thing to make. Definitely not a beginners project.

Because you only need a fixed 1KHz output and if the harmonic content of the output is not so important (if you do not need low distortion) - you might be able to take some shortcuts that will make the design more simple.

Is your load coil very inductive? Can you make it resonate at 1kHz?

You will still need a power supply. Slightly smaller due to the higher efficiency. But still quite expensive.
 
Top