GA Based Optimization Technique for Magnetic Field Attenuation around High Voltage Overhead Transmission Lines Using Mechanical Rearrangement of Power Conductors

Abstract

The magnetic field produced by overhead high voltage transmission lines has received extensive attention owing to its possible biological effects on humanity. The scientific community as well as general public are interested in the possible threats that living things may receive from the magnetic field. This research proposes a magnetic field mitigation approach near an overhead transmission line to avoid negative impact on the population around these lines. Apart from altering human brain activity and heart rate, magnetic fields can also lead to diseases like cancer. As a result, many techniques are employed to lessen that magnetic field. To reduce this magnetic field, scientists are looking for transmission line schemes. The suggested study investigates the influence of mechanical rearranging power conductors on magnetic field mitigation using genetic algorithm (GA) which is one of the evolutionary optimization techniques. The proposed GA has the objective to minimize the magnetic field as a fitness function and the location of conductors as genes considering their symmetry. The proposed method is tested using two published study cases of actual overhead transmission lines resulting in 48.4% and 57% reduction in magnetic field for case 1 and case 2, respectively. The contribution of the proposed method is to provide higher mitigation level of the mechanical rearrangement method depending on different sub-conductors spacing for one phase. The proposed mechanical rearrangement increases the geometric mean radius of the inner phase by optimizing its sub-conductors spacing within allowable critical ranges, thus the practical implementation of the proposed method requires a special design of the inner insulators string to support its sub-conductors.