Mechanical analysis of second order helical structure in electrical cable

A new model for calculating the response of electrical cables to bending has been developed accounting for multi-order helical structure and frictional effects. Stresses occurring in wires and the number of slipping wires were suggested as key properties in terms of expectation of cable life time. The model was applied to chosen cables and the magnitudes of the mentioned key properties were calculated. Parametric study was also done to investigate how these values are affected by changing the properties of the cable. It has been shown that increasing the pressure from jacket or insulation material causes larger stress while it prevents the slippage of wires. Applying a tensile force to the cable produces the same result, whereas using larger lay angles for both conductors and wires decreases internal stress and prevents the slippage.