Reserch On Leakage Magnetic Field And Additional Loss Intransformer With Characteristic Harmonics

Transformer is very important in the electrical equipment, its safety and reliability is getting more attention and focus of the manufacture and operation department. As one of the special transformers, the use of the phase-shifting rectifier transformer is very wide and it contains(6n+1) times the harmonic. Because of the special structure of the phase-shifting rectifier transformer, the current of the network side and the valve side is uneven in the half through runtime. All this causes asymmetry of leakage magnetic field. In the actual application,harmonic will cause greater additional losses and local overheating. So the simulation of the rectifier transformer leakage magnetic field and the additional loss under the harmonic is very important.In this article, the structure characteristics of rectifier transformer is analyzed and the two-dimensional simplified model is established. The leakage magnetic field of transformer is analyzed by both time harmonic field and transient field. And according to the IEC61378-1 calculating method, the harmonic additional loss is calculated. Through the study of the comparison and analysis of load loss under the two conditions, some application results are concluded, this provided the basis for calculating the additional loss of the Phase-shifting rectifier transformer.The last, the 3D model of rectifier transformer has established. Eddy current field and stray loss of transformer have analyzed by the field-circuit coupled method(FCCM). The eddy current loss distribution, leakage magnetic field distribution and the maximum loss density in unit volume of tank wall and clip pieces are calculated. According to the analysis of the factors of affecting the stray loss and the validation of the load loss, showing the calculation method is reasonable.