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1. #SOLAR ELECTRICAL SYSTEM DESIGN IMAGE TOOLS INSTALL#
2. #SOLAR ELECTRICAL SYSTEM DESIGN IMAGE TOOLS SOFTWARE#

! Note that if the substation earth grid is interconnected with that of the solar farm, then faults from the HV side of the substation transformers need to be used in the modelling which will likely result in higher touch and step voltages. If the solar farm has a substation for power grid connection, then this earthing system may be bonded together with that of the solar farm. In general, the amount of buried earthing conductor installed for solar farms is minimised just enough to bond each block of the arrays between the individual inverters and step-up transformers. A buried grading ring is typically run around the outside of any inverter/transformer equipment to reduce touch voltages. Galvanic corrosion caused by contact between dissimilar metals such as copper and steel must be avoided otherwise “tinned” connections may be used.įigure 3 below shows a sample PV panel support structure (part of the auxiliary earthing). The red mark-up on the figure depicts how these structures have been included in the earthing model – the section of metal post in the ground is treated as a rod and these rods have related to insulated conductors. Support posts must be protected from corrosion through galvanising.

The path between panels and supports must be truly electrically continuous. ! Note if the support structures are relied on as part of the earthing systems, then:

#SOLAR ELECTRICAL SYSTEM DESIGN IMAGE TOOLS INSTALL#

Unlike for a typical substation earthing system, the very large area covered by a solar farm makes it impractical to install buried meshes of conductors to achieve a near equipotential plane nor is it practical to install crushed blue metal rock everywhere on the surface to increase safety.Įach row of the solar panel array equipment and support structures is bonded to the main earth system either at each end or in some designs a continuous copper earth cable will be run from end-to-end of a row either above or below ground level. The main earthing system consists of buried bare copper conductors and rods ( Note: earthing rods are rarely beneficial for solar farms), along with the above-ground interconnected metal panel support structures, support posts and cable trays. The DC and AC grounding systems of the solar system are usually bonded to improve the overall earthing system performance. When it is grounded it is done at the ground fault protection device of the inverters. The DC side of the PV system may be either grounded or ungrounded. The DC and AC sides of the system are galvanically (functionally) isolated. The standard earthing system of a solar farm is as follows: The modelling results in this article were performed using SafeGrid Earthing Software. Note that the same practical approaches to earthing used for safe earthing system design of a substation cannot be used for solar farms which is due to their very large size, which results in comparatively higher touch and step voltage hazards. For large solar farms modelling the earth grid will usually involve compromises such the use of as partial, limited, or approximate models (even with the most powerful and sophisticated software), however accurate results are still achievable.

#SOLAR ELECTRICAL SYSTEM DESIGN IMAGE TOOLS SOFTWARE#

Standard rules and guides apply for the practical earthing layout designs while the assessment of safety involves software modelling.

Meticulous design of the solar farms earthing system is required to ensure a functional system as well as personal safety during faults. In this article we are dealing with solar farms of 5 MW or greater in capacity. ! The cost of large-scale solar farm earthing systems can reach millions of dollars hence a small percentage of overdesign will introduce a significant extra cost.

Solar farms can cover large areas (up to tens of square kilometres) which presents both safety and economical challenges for design of their earthing/grounding systems.