Answer: The trefoil formation is created by laying three single-core cables in a triangular configuration, held together by specialized cable cleats. This formation is commonly used for Medium Voltage (MV) and High Voltage (HV) applications.

The main advantages of the trefoil formation are:

• Reduced Induced Currents: The close proximity of the three phases balances the magnetic fields, significantly reducing induced currents and losses in the cable sheaths.

• Minimal Electromagnetic Interference: This balanced formation minimizes external magnetic fields, making it the preferred choice when laying cables near sensitive control or communication lines.

• Compact Installation: It requires less trench width compared to a flat formation, which can be advantageous in constrained or congested areas.