Power capability of PFS 7529H

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Hallo,

we have to design a power supply with dual power output of +- 21VDC for use in a Power amplifier. Power rating of the amoplifier is 12V/ 15A Rms. eg. 180W.
I want to use PFS 7529H combined with TFS7708H in an CV/CC configuration, because we have to generate also some minor outputs +-15V, 5V with approx. 15W Output power.
My question: because of using the main outputs in an Class AB Amplifier Power stage., the peak current of the stage will be about 21 Apeak. This means a power of 440W. Having an estimated efficiency of 90% of at TFS 7708 stage we get about 490W peak ooutput power for PFS7529H.
Referring to the data sheeet the maximum is 450W Output power for this device.
what is the behaviour of the device in this case?

Will it switch off completly or is it a kind of cc mode then with regulating output current rather then output voltage?
This would be helpful for me since the TFS 7708 Stage can deliver the desired output peak power and can use the enrgy stored in the bulk capacitor to hold up Power level for the time peak power is needed.

If so what about PFC regulation at this timeof beeing in peak power mode? Is this interrupted at this time?

Thank you for an answer.

Best regards

A. v. Müller

Hi Muller,

Thank you for your interest in PI products. May I know the input voltage range and peak power duty (on and off times)?

Hallo,
we have a worst case scenario with about 490W output power for the PFC regulator of about 1,5s with a duty cycle of 0,3, but this is a sinusoidal current flowing in the output and not a pulse load. so the average of this overload should be less than that of a pulse load with duty cycle 0,3.

Hi Muller,

For universal input range (90 to 265VAC) the peak power is limited to 450W @90VAC. When input operating voltage is increasing, output power goes up proportional to input voltage. It has two input peak current limits, one at low line and other one at high line. Peak current limit at lowline> high line. When load draws more output power than rated power, output voltage regulated below regulation voltage to limit the output power. Please check the datasheet for peak current limits at low and high lines.