Variable input Constant output DC to DC converter for photovoltaic application.?

Question

I'm currently now doing a research of photovoltaic application in generating power for consumer. My problem is that I need to find circuit of the variable input constant output dc to dc converter in the photovoltaic application to do the analysis. Where can I found such circuit?

Answer 1

If you want voltage to vary on the input and remain constant out, try using this chip: AP34063.  Available at digikey.ca

Answer 2

IF INPUT VOLTAGE IS HIGH:

A boost regulator (converter with feedback) circuit can do the trick for you. Be wary though. Boost converters are hard to regulate.

IF INPUT IS Voltage is LOW:

Use a buck regulator can do the trick for you. They are easier to build than boost regulators.

Answer 3

Are you serious?  I'm doing the same thing, but not as a product, just playing around.

My intention is to use an LM5020-1 as the PWM controller, accept a variable 150 to 350 VDC input, and generate a selectable outputs:

1) 160 VDC to power devices with switching power supplies meant for 120 VAC.

2) 320 VDC to power devices with switching power supplies with a switch on the back to select between 120 or 240 VAC (it has to do with the internal double/no-double design of these older supplies).

3) 100 VDC to power devices such as small power tools.  Many AC motors will actually run off DC, but you have to watch the voltage because the windings have lower impedance at DC.

My device uses a heavy gauge, 20 uH torroid, and a number of other parts that I was able to harvest out of junked server power supplies.  About the only thing I had to buy was the main switch (FET), and a high current, high voltage, ultrafast diode.  It's a buck-boost topology, and has really crappy output regulation, but that doesn't matter for the purposes listed above.

If you email me (see my profile), I can send you a schematic.

Power circuits are nothing to be trifled with.  My circuit is a first-order design, and I guarantee NOTHING about it.  It's probably unsafe.  You'd need all sorts of other things, like proper fusing, to pass UL.  There is no other protection on the circuit.  The output is NOT isolated.  The snubbers have not been tuned, so not only would the circuit probably not pass EMI requirements, it would be less than optimally efficient, and could burn itself out quickly.  Only use the schematic as a concept, and get a seasoned switching power supply designer to clean it up, ok?

Answer 4

This is basically a DC-DC switching type converter.

here is one low power example

http://www.national.com/pf/LM/LM2698.htm...