Title:
CONTROLLING FOR CHOPPER
Document Type and Number:
Japanese Patent JPS5480514
Kind Code:
A
Abstract:
PURPOSE:To surely minimze the turn-on ratio of a chopper, by the output signal of a saturable reactor having no time relation with the operation of the chopper. CONSTITUTION:A pulse width comparator circuit PWC is used so that the pulse width of a reference pulse signal equal to the commutation period of the chopper is subtracted from the pulse width of the output signal of the saturable reactor SCT. The output signal of the pulse width comparator circuit is pulse-converted by a controller CE into a turn-off gate signal. The turn-off gate signal is applied to an OR gate to be applied as a turn-on gate signal to the copper CH to minimize its turn-on ratio. At whichever timing the saturable reactor operates, no continuous gate signal is applied during the commutation period of the chopper. Thus, the commutation failure of the chopper and the damage of circuit elements are prevented.
Inventors:
SATOU HIROSHI
NOZAKI YOSHIO
NOZAKI YOSHIO
Application Number:
JP14815077A
Publication Date:
June 27, 1979
Filing Date:
December 12, 1977
Export Citation:
Assignee:
HITACHI LTD
International Classes:
H02P3/12; H02M3/135; (IPC1-7): H02M3/135; H02P13/32