Optimum Utilization of Magnetization Characteristics for Power Capacity Enhancement of the Transformer and Considerable Saving in Core Cost

摘要

In the normal working of a transformer, the transition along the magnetization characteristics during each half cycle goes from zero value to its respective maximum value (limit up to knee point) on the positive side during the positive half cycle and on the negative side during the negative half cycle. The new concept introduced in this paper involves a square-wave excitation along with sinusoidal input. The square-wave excitation shifts the position of operating point on the B-H curve depending on the positive half cycle and the negative half cycle to exploit a double range of the linear portion of the B-H curve. This provides a double rate of change of flux, and therefore, voltage range can be doubled. If the voltage range can be doubled, then the current range can also be doubled (if the load impedance is kept constant) and the power capacity can be enhanced substantially, assuming that sufficient insulation level and proper conductor size are provided to withstand higher voltage and current.