The primary distribution system facilitates the transmission of electricity from high-voltage transmission lines to consumer-end distribution transformers.
The primary radial system, most prevalent in low-load density areas, consists of individual three-phase feeder mains.
Lightning flashovers or momentary contact incidents can cause temporary faults. These faults are effectively managed by automatic reclosing devices that momentarily open the circuit during a fault and then promptly reclose it.
Sectionalizing fuses and shunt capacitor banks play crucial roles in fault isolation and voltage management.
The primary loop system is designed for areas that require high service reliability. This system loops around a load area and reconnects to the distribution substation, providing a two-way feed and ensuring power supply even in a fault.
The system employs reclosers and tie switches to reduce customer interruptions and isolate faulted sections of the loop.
The primary network system is typically found in areas with high load densities. This system utilizes a grid of interconnected feeders supplied from multiple substations.
Smaller, self-contained unit substations at selected network locations can replace conventional distribution substations.
