Upload
solar-scot
View
440
Download
4
Tags:
Embed Size (px)
DESCRIPTION
Visit http://buildyourownsolarpanelshelp.com for more information
Citation preview
2. PV Components
The module is the smallest component of the PV system. This is a
connected set of solar cells which have been sealed to protect
themselves from the environment.
A group of modules attached together is known as a panel.
Groups of panels are then put together to make a sub-array, which
is the part of an array assembly that can be considered a unit and
delivers some fraction of the total system output.
An array, is an assembly of subarray, panels or modules (or a
combination of these) which includes a support structure but no
non-pv components.
The array-field is a collection of all the arrays in the
system.
3. Modules
The module is a collection of solar PV cells connected in series
and sealed for protection against the environment.
Generally sold in any size (5-150W).
Typically the cells sit in an encapsulant (EVA) sandwiched between
the front cover and the back protection.
Moisture proof backing is generally used. There is also a terminal
box where the cables to connect the module are found.
4. Array Field
Modules are connected into series strings to provide the correct
voltage.
Modules in a string are matched as the module with the lowest
current determines the string current.
By pass diodes are also used across the modules to limit any damage
due to mismatch (hotspots).
The strings are then matched in terms of total voltage and
connected in parallel to provide the required system current.
A blocking diode is connected in series with each string to prevent
battery discharge at night.
5. Array Field
Modules are connected into series strings to provide the correct
voltage.
Modules in a string are matched as the module with the lowest
current determines the string current.
By pass diodes are also used across the modules to limit any damage
due to mismatch (hotspots).
The strings are then matched in terms of total voltage and
connected in parallel to provide the required system current.
A blocking diode is connected in series with each string to prevent
battery discharge at night.
6. Balance Of System Components
The BOS components, non-PV components, contribute significantly to
the system. They are separated into electrical and mechanical
components.The electrical components include the following:
Battery, cables, fuses, earthing, inverters, Maximum Power Point
tracker, protection against lightning, charge regulation.
Mechanical components include the mountings which can be fixed or
track the sun. Trackers must work automatically so add to the
complexity of the system. Array racks can be stand alone or
integrated into building structures. This requires consideration of
the roof and wall materials.
7. System Configuration and Performance
System Configurations
PV Systems can be stand-alone, with storage / backup (battery) and
grid connected (ie. Deliver power to the electricity grid). Storage
/ Backup is needed if the system is to deliver continuous power.
Grid connected systems can be made to supply all power to the grid
and also just to use the grid as a backup.
System Performance
Performance of a PV system measured by the performance ratio.
(Ratio of actual energy obtained over a period to the ratio of
theoretical energy). Good systems have PRs of over 80% with
anything under 60% needing investigation.
8. Find Out More At:
http://buildyourownsolarpanelshelp.com