Solar Simulator (Power Supply)

[Trevor Lim]

Hi Peepz,

I have a project at hand which requires me to use a LM723 IC to create a solar simulator, which actually is a power supply that simulates to be like a Photovolatic Cell.

Anyone has any ideas on the go about for this project?

Warmest regards,
Trevor

 

[MikeMl]

How realistic do you want the "solar simulator" to be?

Look at the attached I-V plot. It shows the output current vs the output terminal voltage of a panel that I own. Note that it has a very soft curve; not a like a current-limited regulated power-supply such as a 723 chip would provide. You will have to obtain the I-V curve(s) of the specific panel(s) you want to model from the Panel's maker.

One way to simulate the I-V behavior is to built a voltage regulator which controls the simulated panel voltage as a function of panel current. Sample the panel current being drawn from the simulated panel, convert it to a voltage, feed that back to an OpAmp which has several diodes/zener diodes and resistors in the feed-back loop so as to do a piece-wise linear fit of the Panel's I-V curve.

Another way is to control the simulated panel current as a function of the simulated panel voltage.

You might be able to fit the diodes/resistors in the feedback loop of a 723?

 

[Trevor Lim]

Solar Simulator

Hi MikeMI,

I don't really get the picture on the feedback loop thingy.

My supervisor didnt really indicate how realistic he wants it to be, but he did pass me one of the BP's PV cell IV chart.

Do you have any example circuit that I can reference?
Thanks.

Best regards,
Trevor

 

[ericgibbs]

Hi MikeMI,

I don't really get the picture on the feedback loop thingy.

My supervisor didnt really indicate how realistic he wants it to be, but he did pass me one of the BP's PV cell IV chart.

Do you have any example circuit that I can reference?
Thanks.

Best regards,
Trevor

hi,
If you are familiar with operational amplifiers [opa] then the method is to use a combination of resistors and diodes/zeners as part of the feedback path.

By doing this, the gain curve of the opa can be made to approximate the 'shape' of the PV cell. Sometimes called 'chords' or PWL piece wise.

OK.?

EDIT:
To suggest a circuit we need to see the profile of the PV under test also the PV spec.