SolarMagic, Solar Magic – Part 2

SolarMagic Outside Demo on the Freigelände at Intersolar 2009.

After visiting the SolarMagic stand, I managed to swing by the SolarMagic outside demo opposite Hall B5 before the National Semiconductor Corporation (NYSE:NSM) Intersolar 2009 SolarMagic press event (please see SolarMagic, Solar Magic).

I received a cordial reception in contrast to my previous experience as the Photovoltaic Blogger banned from SolarMagic “Sneak Peek” Show.

From Intersolar 2009: SolarMagic Outside Demo on the Freigelände

After waiting for a group to finish (yes, I can be patient at times), I got the demo run through by Ms. SolarMagic herself. The demonstration setup had two side by side arrays each consisting of two parallel strings with two modules each for a total of four (4) modules per array. Suntech Power Holdings Co., Ltd. (NYSE:STP) Model Number STP190-18Ub multicrystalline silicon photovoltaic (PV) modules were used in both arrays.

In the above photo, the left array was the Reference System while the right array was the SolarMagic System. First, the power and current in each string of the systems was verified. I didn’t snap a screenshot of the demo monitor at the start but I did photograph the equivalent at the end. It was overcast with the sun in and out, so the modules were only producing about 32% of rated power.

Next a pad cloth larger than a single solar cell was placed on the lower right module of each array at the same approximate location. The cloth had a lattice of material allowing light to pass through simulating shade conditions or an impairment. Going back to the demo monitor, the SolarMagic System delivered 25% percent more power (44 Watts) than the Reference System as shown in the photo below. The Reference System string current, I2, had been halved because of the cloth.

From Intersolar 2009: SolarMagic Outside Demo on the Freigelände

Once the cloth was removed, both arrays resumed producing close to 120 Watts per string as shown in the next photo. So the classic A to B comparison made for a compelling SolarMagic power recovery demo.

From Intersolar 2009: SolarMagic Outside Demo on the Freigelände

Behind the SolarMagic System, the SolarMagic Power Optimizer per module was obvious but the Blocking Diode per string could also be seen. As I recall, the Reference System was also fitted with one Blocking Diode per string for comparability. SolarMagic’s blue LED blinks like a heart beat function when powered. When I first saw this, I thought the blinking indicated a state where SolarMagic was compensating for some sort of mismatch. In my experience, blinking indicates a problem.

From Intersolar 2009: SolarMagic Outside Demo on the Freigelände

Later in the week, I returned to try another experiment. I was curious if it was possible to get the SolarMagic unit to turn off if a PV module was 100% bypassed. Once my idea was communicated and understood, the demo folks let me give it a try. Well, the string power never went below 20 Watts; plenty to meet SolarMagic’s 5 Watt minimum PV module power requirement.

One ironic twist of the SolarMagic demo was the importance of monitoring, even at the string level, to observe system performance. This is a capability SolarMagic equipped installations will not have relative to the competition’s per module performance monitoring.

Solmetric, Inc. VP of Sales and Marketing Peter Hoberg is scheduled to present “Shade Matters” at this Wednesday’s, June 10, 2009, meeting of the Silicon Valley Photovoltaics Society (SVPVS).

I trust he will demonstrate the PV Simulator tool for analyzing PV system design performance with National Semiconductor’s SolarMagic per “Solmetric to Develop Photovoltaic Layout and Estimation Software Tool for SolarMagic Power Optimizers”.

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