Solar panel manufacturing steps
·
Solar Cell Testing
The equipment is developed to an automated work unit which
characterizes PV cell efficiency using a current-voltage (I-V) test. I-V test
subjects a PV cell to a calibrated light source to generate electrical current
at different voltages. Using this data, the cell’s efficiency can be
characterized. The system then sorts the PV cells according to eight different
efficiency ratings for subsequent use in solar panels where cells with similar
efficiencies are grouped to maximize the overall panel efficiency.
·
Solar Cell Cutting
Solar cell standard size is 156mm × 156 mm size, sometime
cell having 125 mm × 125 mm size. For making different size panels the cell
must be needed to cut in custom size. After cell testing, the cell is cutting
in solar cell laser cutting machine. This machine is fully automated machine in
which size we want to cut cell that size is logged in automated software
system.
·
Solar Cell Tabbing and Stringing
Tabbing and bussing are two applications that link
individual solar cells together to form a solar module (or solar panel). These
applications also provide a method to transfer power from the solar cells to a
power output, the junction box. Solar cell interconnect occurs when individual
solar cells are joined together with tabbing ribbon (also called stringing
ribbon), forming a cluster of solar cells. This is frequently referred to as
cell tabbing (or stringing). The tabbing ribbon carries the solar cell’s
current to a larger ribbon, the bus ribbon, which then carries power from the
cell clusters to the module’s junction box for final output.
Tabbing ribbons are commonly applied as parallel strips that
weave from the top of one cell to the bottom of the next to connect the
positive and negative sides of the cells in series. The ribbon is soldered onto
the paste that was applied to the TCO. The tabbing application creates a
cluster of solar cells. Once all of the cells have been strung together with
tabbing ribbons, they are then placed onto a substrate, typically glass. Then
the thicker bus ribbon is soldered so that it connects to the tabbing ribbon of
each solar cell cluster. The tabbing ribbon collects electric current within
its cluster of solar cells and delivers it to the bus ribbon. The bus ribbon
then conducts the cumulative electric power from all of the solar cell clusters
to a junction box for final output. Imagine tabbing ribbon as a road that
travels across the solar cell. The bus ribbons serve as the highways to connect
and tie them together. Bus ribbon is larger in cross-section because it has
more electrical power to carry.
·
Solar Panel Lamination
Lamination
is the major process in solar module manufacturing. In this process, all
materials are pressed into laminate as a whole. In the first stage, air in the
chamber of the machine is pumped out and turned to vacuumed. Then, heating at
150 ° C and pressing will laminate all the materials together. Normally whole
lamination cycle (including loading and unloading time) is approximately 6
minute.
·
Trimming & Framing
Debris
and uneven edge surface of panel caused in lamination are trimmed to smooth and
even in this process by using knife. Silicon glue is spread on aluminum frames
manually, then operators collect the glued frames and fix them onto the panels
manually, after that, operators load the panels on the framing machine, and
frames are fastened and locked by framing machine.
·
Junction Box Fixing
In
this proposal, silicon glue is spread on back side of junction boxes manually,
and then the junction box is fixed manually on the back side of the panel.
·
Cable Connection
Cables are connected from the junction box for output
power of the panel. This cable called MC4
connector.