Five key considerations in AC side system sizing for your solar power plant

The AC side design of a solar power plant is critical to ensure that the generated energy is efficiently distributed to the grid. The design should be such that it provides reliable, safe, and cost-effective power transmission. In this article, we will discuss five key considerations in AC side design of your solar power plant.

1. Fault Breaking Capacity: One of the most crucial considerations in AC side design is fault breaking capacity. It refers to the ability of the switchgear to break the fault current safely and reliably without damaging the equipment. The fault current is the current that flows in the circuit when there is a fault in the system. The fault breaking capacity of the switchgear must be higher than the maximum fault current expected in the system. In this regard, the HT switchgear with a fault breaking capacity of 25 kA for 1 sec is suitable for the solar power plant.
2. Switchgear: The choice of switchgear plays a vital role in AC side design. The switchgear should be reliable, efficient, and easy to maintain. In this regard, a draw-out type vacuum circuit breaker is suitable for the solar power plant. The breaker current rating should be as per design requirements. The switchgear’s enclosure degree of protection should be IP 4X for indoor and IP 54 for outdoor applications, which ensures protection from dust and water.
3. Bus Bars: Bus bars are the electrical conductors that distribute power from the switchgear to the load. The bus bar should be made of copper, as it has high conductivity and is corrosion-resistant. The bus bar rating should be as per design requirements.
4. Surge Arrestors: Lightning strikes and switching surges can cause voltage surges in the system, leading to equipment damage. Surge arrestors are installed to protect the system from such surges. It is essential to provide surge arrestors at the outgoing feeder of the switchgear.
5. Cable Accessories: The selection of cable accessories is another critical consideration in AC side design. The accessories should be compatible with the cable size and insulation type. Heat shrinkable jointing kits are suitable for HT cables. The accessories must conform to relevant standards such as IS 1255 and IS 7098.

The AC side design of a solar power plant is crucial to ensure reliable and efficient power transmission. The above-discussed key considerations are essential to ensure the proper functioning of the system. It is essential to adhere to relevant standards such as IS 2516, IS 2705, IS 3156, and IS 13118 for switchgear and IS 1255, IS 7098 for cable accessories. By considering these factors, solar power plant owners can ensure their system’s safety, reliability, and cost-effectiveness.