Magnetic field calculation for indoor substation busbars based on analytical-numerical method

Power frequency magnetic field (PFMF) has possible health hazards for persons. In resent years PFMF of indoor substation has been paid more and more attention. Busbars with heavy current are the main source for PFMF. The paper presents the calculational model for the PFMF. Analytical approach and numerical approach are combined to calculate the magnetic flux density in the space nearby the busbars. The influencing structure factors of the busbars such as their length, spacing and breadth are discussed. This proposed method is more accurate and effective to evaluate the magnetic environment in the substation. The research results can be used as the reference to set the restrictive maximum values of power frequency magnetic flux density for construction.