Phase Selection Method for 10 kV Three-Core Cables Under Single-Phase Grounding Fault Transient Based on Surface...

Area of Science:

• Electrical Engineering
• Power Systems
• Sensor Technology

Background:

• Single-phase grounding faults are common in urban power distribution.
• Existing sensors struggle to identify the faulted phase in belted cables due to unchanged magnetic flux.
• 10 kV belted cables are prevalent in distribution networks.

Purpose of the Study:

• To develop a method for distinguishing the faulted phase in 10 kV belted cables during single-phase grounding faults.
• To overcome limitations of traditional ferromagnetic zero-sequence current sensors.

Main Methods:

• A two-step methodology employing an annular Tunnel Magnetoresistance (TMR) magnetic sensor array.
• Measuring magnetic field intensity at six points on the cable surface.
• Calculating rotation angles using a differential evolution algorithm and identifying the fault phase via magnetic field intensity differences.

Main Results:

• The proposed method achieved relative errors of less than 1% in calculating rotation angles.
• Accurate identification of the faulted phase under single-phase grounding fault transients was demonstrated.
• Successful validation through both simulation and experimental verification.

Conclusions:

• The developed methodology effectively identifies the faulted phase in 10 kV three-core belted cables during single-phase grounding faults.
• The approach offers significant engineering application value for power distribution systems.
• This sensor-based technique provides a reliable solution for fault phase discrimination.