Technical discussions of CEDM power supply using PWM methodology

The design elements of CEDM power supply system were analyzed based on reviews of electro-mechanical phenomena of CEDM. Several improved items were discovered as the results of reviewing conventional CEDM power supply systems. The major items is to supply over-power to CEDM due to applying over-estimated design margin of holding current, because of unstable power quality of the conventional system. While the suggested method based on pulse width modulating methodology can be reduced the amount of supplied power and dissipated heat of coils when holding power is supplied. In addition, as a method to reduce the drop out delay, the negative voltage applied method was suggested. But there are still remain some shortcomings such as increase of component complexity, etc. regarding the suggested power supply method