[Embedded System Application] Control System for Solar Energy Equipment

Fanless Embedded System as the Control System for Solar Energy Equipments

Project

Demand for alternative energy sources is growing amid concerns over global warming, especially in China, where the government has vowed to invest heavily in renewable energies, which has resulted in a surging demand for solar energy equipment.  Our customer is one of the biggest suppliers of solar energy equipment in China, whose products include single crystal pullers, poly-crystal growers, cutting machines and solar cell makers.

Advantech has been cooperating with this company by providing rugged, compact, low-power, fanless, embedded ARK-3360 IPCs, which the customer mainly uses as control units in the single crystal growing apparatuses which compose a large portion of their product line. The monocrystalline silicon ingots these machines produce are ultimately sliced into wafers and made into high efficiency solar cells.

System

The single crystal growers manufactured by our customer use the Czochralski, or CZ, method of pulling single-crystal silicon cylinders.  A load of 95kg, 120kg or 135 kg of granular silicon powder (the material loads vary with different machine types) is placed into a crucible and heated until molten. When the temperature is just right, a seed crystal is dipped into the molten mass and withdrawn slowly, spinning all the while. Lift rate is on the order 10 mm per hour; and spin, 15 rpm. The mass of silicon crystallizes around the seed and may be pulled into a large, single-crystal cylinder, a maximum of 200 cm in length and 6 or 8 inches in diameter. The operating temperature in the furnace can be as high as 1600 degrees Celsius. Temperature, spin, and pull rate are all precisely controlled (by complex, secret formulas) in order to produce a homogenous crystal of the desired diameter. Needless to say, this is a process where dependability and accuracy are crucial. Each single crystal growth apparatus has two ARK-3360 units inside, and they are connected to various components, including the furnace, the mechanical pump, the water cooling unit, the control panel, and the display.

Conclusion

The development of clean and renewable energy sources helps protect our planet and preserve it for coming generations. The practical application of green energies depends not only on the availability of the technology, but also on whether the price of that technology is affordable. While the solar industry shares similar wafer production processes with those of the semiconductor industry, the latter often has more stringent requirements for cleanliness and quality control.  But for the solar industry, the goal is to generate maximum quantities in the shortest amount of time to realize cost-effective mass production. The ARK-3360 is able to edge out its competitors in this field with its compact size, reliable operation, power efficiency, and attractive price.