Earthing and lightning protection system is an essential component of any solar power plant. Proper earthing and lightning protection system ensure the safety of equipment and personnel, prevents damage to equipment and interruption of power supply. In this article, we will discuss five key considerations for earthing and lightning protection system for your solar power plant.

  1. Earthing Calculation and Soil Resistivity

The first and foremost consideration for earthing is to calculate the earth fault current and soil resistivity. Earthing systems are designed to keep the earth potential rise (EPR) within safe limits. Earthing resistance depends on soil resistivity, and therefore, it is important to conduct soil resistivity tests. The GI strip size should be decided as per earthing calculation and soil resistivity.

  1. Earthing of Transformer and Power Conversion Unit (PCU)

Earthing of transformer and PCU is critical to ensure the safety of equipment and personnel. For neutral earthing of the transformer, treated earth pits will be provided. Since the PCU used in this power plant is of transformer-less type, all live parts of the PV installation shall be insulated from earth.

  1. Lightning Protection

Lightning protection is essential for the safety of the solar power plant. Lightning arrester shall be supplied for lightning protection of the array yard and monitoring system. Direct lightning strike covering a radial distance of maximum 107m should be considered during the design of the lightning protection system. Power transformers and lightning masts shall be provided with separate earth pits.

  1. Earth Mat for Pooling Substation

Pooling substation is an important component of a solar power plant, and it is essential to provide earth mat for the pooling substation. The earth mat provides a low impedance path for the earth fault current, thereby ensuring the safety of the equipment and personnel.

  1. Insulated Ground Wire for UPS and SCADA

The UPS and SCADA systems are critical components of the solar power plant, and therefore, it is important to earth these systems properly. An insulated ground wire should be used to earth the UPS and SCADA systems to a separate earth system.

Earthing and lightning protection system is a critical component of a solar power plant. Proper earthing and lightning protection system ensure the safety of equipment and personnel, prevents damage to equipment and interruption of power supply. The earthing calculation and soil resistivity, earthing of transformer and PCU, lightning protection, earth mat for pooling substation, and insulated ground wire for UPS and SCADA are the key considerations for earthing and lightning protection system for your solar power plant.