Effects of Harmonics on Power Loss in XLPE Cables

W. Z. Gandhare, K. D. Patil

Principal, Government College of Engineering Amravati, India.
Research Scholar, Government College of Engineering Aurangabad, India.

DOI: 10.4236/epe.2013.54B234                

Abstract

Harmonics in power systems is increasingly at high level. Also, there has been an incredible growth in the use of cross linked polyethylene (XLPE) cables in distribution systems. Harmonics cause additional power loss/temperature rise; causing premature failure of cables. Catastrophic failure of power cables leads to great inconvenience to consumers and loss of system reliability and money. To avoid the overheating of power cables; the additional power loss due to harmonics should be accurately calculated and properly accommodated by derating the cable. The present method of calculating the power loss in cables in harmonics rich environment is very arduous. The aim of this paper is to present the reasonably accurate method for evaluating effects of harmonics on the power loss in XLPE cables. Computational model is developed in MATLAB for power loss calculation using conventional method. Using this model, calculations are performed for aluminium and copper conductor XLPE cables of different size and type; for three different types of harmonics spectrums having total harmonics distortion (THD) of 30.68%, including all odd harmonics components up to 49^th order. Using these results; a mathematical model in the form of simple empirical formula is developed by curve fitting technique. The results obtained by various models are presented and compared with error justification.

Keywords

Curve Fitting; Non-sinusoidal Power Loss; Per Unit Harmonic Load; Quadratic Polynomial; Sinusoidal Power Loss

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	IEEE Recommended Practices and Requirements for Harmonic Control in Electrical Power Systems, IEEE Standard 519-1992.
[2]	IEC Standard 60228 - Conductors of Insulated Cables, 3rd edition, 2004-11.
[3]	IEC Standard 60287-1-1 - Electric Cables - Calculation of the Current Rating, edition 1.2, 2001-11.
[4]	IEC Standard 60502-1-1 - Power Cables with Extruded Insulation and Their Accessories for Rated Voltages from 1 kV up to 30 kV, part-1: Cables for Rated Voltages of 1 kV and 3 kV, 2nd edition, 2004-04.
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