Calculation Methods of Power Frequency Magnetic Field around the Three-phase Heavy Current Bus Bars

In this paper,it builds the calculation model for the three-phase heavy current bus bars and studies difference methods to calculate the magnetic field distribution around bus bars. The results show that the distributing trend of magnetic field is assumable consistence. Under the condition of accuracy is not very high,the simple numerical approach can be used,but if it requests the error is very small,the skin effect of large current bus bars must be considerate,and the simulation current method of analytical approach is more precise.