| 摘要 |
PROBLEM TO BE SOLVED: To control the density of residual magnetic fluxes in a transformer iron core to a desired value.SOLUTION: The method includes: an initializing step (S1) of applying a DC voltage to a transformer to bring it into a positive saturated state; a saturation energy calculating step (S2-S5) of applying a negative DC voltage, in a direction reverse to the initializing step, to the transformer brought into the saturated state by executing the initializing step to bring it into a saturated state, then interrupting the application of the DC voltage, and obtaining a first integrated value V1 obtained by integrating a voltage value Vi of the DC voltage according to the energy for saturation required from start of application of the DC voltage to interruption; and a step (S7-S10) of applying a positive DC voltage which is the same as the DC voltage applied in the initializing step to the transformer by the amount corresponding to energy which is one half the energy V1 obtained in the saturation energy calculating step. As a result, the density of residual magnetic fluxes is reduced to zero. The density of residual magnetic fluxes can be optionally set by setting energy applied by a positive DC voltage to X% of V1. |
