Research on the impacts of DC-bias on the loss and temperature rise of the transformer

The work point of the transformer under DC bias will shifts, and its iron will be saturated which affect the normal work of the transformer seriously. This gives rise to lots of bad influence, for example, the peak value of the exciting current increases significantly, and the waveform of the current is seriously distorted with a lot of harmonics; the heavy noise; the serious vibration; the increases of transformer’s leakage and losses and temperature build-up; the local heating of metal structures; the malfunction of relay protection devices of electric power system; which endanger the operation safety of the transformers and electric power system. So the DC bias phenomenon of the transformer is concerned.