1.5kVA @ 2.1kV = 714mA / 1.5-2 (RMS derating) = around 400mA. You can draw more at the expense of greater temp rise and voltage drop.
Tim
Tim
Are you sure that's right? The diodes only conduct near the peaks of the voltage waveform, and so you can't just divide by the RMS. At 400 mA, LTSpice shows RMS about 2.4 kW!
In the image, the load has 100 mA sine superimposed on the 400 mA DC because I wanted to simulate how much voltage would vary; the voltage source sine amplitude is 3050 as that's peak voltage, giving close to 2100 RMS.
In the image, the load has 100 mA sine superimposed on the 400 mA DC because I wanted to simulate how much voltage would vary; the voltage source sine amplitude is 3050 as that's peak voltage, giving close to 2100 RMS.
An externally hosted image should be here but it was not working when we last tested it.
Well, whatever. Standard derating is 1.4 (equivalent to AC RMS > DC peak change) to 2 times (good SOA).
Tim
Tim
SOA? I'm not familiar with that abbreviation.
OK, so 400 then. I'm just curious what's wrong with the simulator. Or is there nothing wrong and I should be looking at the Average number (1.25 kW) instead of the RMS?
BTW, the only mains IEC plugs with built in EMI/RFI filters I could get cheaply go up to 10 A. I wonder how conservatively rated they are. The only series device inside is a common mode choke, the rest are capacitors and in parallel. I'll have to measure the power factor somehow and correct it if it's not 1, otherwise I'll fry these mains filters.
OK, so 400 then. I'm just curious what's wrong with the simulator. Or is there nothing wrong and I should be looking at the Average number (1.25 kW) instead of the RMS?
BTW, the only mains IEC plugs with built in EMI/RFI filters I could get cheaply go up to 10 A. I wonder how conservatively rated they are. The only series device inside is a common mode choke, the rest are capacitors and in parallel. I'll have to measure the power factor somehow and correct it if it's not 1, otherwise I'll fry these mains filters.
What do you think about that, using a 10 A mains filter? I was hoping to run the transformer at 1200 W, but if the power factor is not 1, wouldn't it draw more than 10 A from the mains, and overheat the choke in the filter? BTW, would the use of a mains DC blocker as discussed in other threads change the power factor?
The transformer is leaking. A lot. The steel chassis it's in sings loudly with magnetostriction.
Hmm, I just calculated that Bmax looks to be about 1.7 T, which is above saturation for the core material. Looks like I'll have to add more turns to the primary and loose some secondary voltage. Dropping secondary voltage to 2.6 kV brings Bmax just below 1.5 T, which is probably just under saturation, but I can't afford more loss in output voltage.
Hmm, I just calculated that Bmax looks to be about 1.7 T, which is above saturation for the core material. Looks like I'll have to add more turns to the primary and loose some secondary voltage. Dropping secondary voltage to 2.6 kV brings Bmax just below 1.5 T, which is probably just under saturation, but I can't afford more loss in output voltage.
peak voltage
I have tonnes of these transformers. I tore the "I" section off of 2 of the same transformers, and stacked the "E" s together. Potted them in a coffee can. I get 2500VDC unloaded off just one secondary. Loaded up it goes down to 1750VDC. And is rock stable into a bank of 175WVDC caps 20 of them in series for 3500WVDC. One transformer is the same just half the power. The secondary's of these transformers make great chokes too.
The caveat is they have welds on the laminations to hold together the core. These welds act a shorted turns, and draw copious amounts of power up to 800 watts depending on the transformer. And that's with no load.
Lastly these suckers can kill you. I've been lucky I've only lost my 2 best DMM's to the ways of 1750VDC.
I have tonnes of these transformers. I tore the "I" section off of 2 of the same transformers, and stacked the "E" s together. Potted them in a coffee can. I get 2500VDC unloaded off just one secondary. Loaded up it goes down to 1750VDC. And is rock stable into a bank of 175WVDC caps 20 of them in series for 3500WVDC. One transformer is the same just half the power. The secondary's of these transformers make great chokes too.
The caveat is they have welds on the laminations to hold together the core. These welds act a shorted turns, and draw copious amounts of power up to 800 watts depending on the transformer. And that's with no load.
Lastly these suckers can kill you. I've been lucky I've only lost my 2 best DMM's to the ways of 1750VDC.
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