Numerical simulation of cable sheath damage detection based on torsional mode guided wave

Area of Science:

• Engineering
• Materials Science
• Non-destructive Testing

Background:

• Power cable sheaths are susceptible to cracking and damage from mechanical stress and impacts.
• Effective detection of sheath damage is crucial for maintaining power system reliability.
• Existing methods may lack the sensitivity or quantitative analysis needed for precise damage assessment.

Purpose of the Study:

• To investigate the echo parameters of cable sheath damage detection using torsional guided waves.
• To establish a quantitative relationship between cable sheath damage and guided wave echo characteristics.
• To develop a reliable method for identifying the location and size of sheath damage.

Main Methods:

• Solving the dispersion curve of magnetostrictive guided waves in cable sheaths using the Navier displacement equilibrium equation.
• Selecting the non-dispersive T(0,1) mode for guided wave propagation.
• Calculating displacement fields and echo parameters considering excitation frequency, loss rate, and damage direction.
• Analyzing time-domain signals to derive a cubic fitting function for damage assessment.

Main Results:

• The T(0,1) torsional guided wave mode was identified with a group velocity of 1198.8 m/s and no dispersion.
• A cubic fitting function was obtained relating the damaged section's loss rate to its echo coefficient.
• The study established a quantitative link between damage location/size and guided wave echo signals.

Conclusions:

• The proposed method effectively characterizes the quantitative relationship between cable sheath damage and guided wave echoes.
• This technique offers a promising approach for non-destructive detection and assessment of power cable sheath integrity.
• The findings contribute to improved power cable maintenance and reliability through advanced diagnostic tools.