Title:
CONTROLLING METHOD OF PWM SWITCHING FOR THREE-PHASE BRIDGE CURRENT TYPE INVERTER/CONVERTER
Document Type and Number:
Japanese Patent JPS56148182
Kind Code:
A
Abstract:
PURPOSE:To optionally obtain a 3-phase AC current wave form by a method wherein commutation pulse signals are obtained by comparing with two kinds of triangular wave forms different by 90 deg. in phase from each other and the wave form for comparison and made the signals in the 3-phase bridge circuit. CONSTITUTION:The two kinds of the triangular wave forms et1, et2 different by 90 deg. in phase from each other and absolute value wave forms eS1, eS2 of the other two phase currents excluding a current wave form in the phase of the largest absolute value among optional 3-phase set current wave forms iUS, iVS, iWS are compared with each other to obtain the commutation pulse signals P1, P2, and further, a commutation pulse signal P3 is obtained from those common pulse arrays. Those commutation pulse signals are allowed to select switching arms S1-S6 of the 3-phase bridge according to current polarities of the respective phases and to make short-circuit actions only in the section of a pulse signal P4 logically inverted and the same procedures are repeated at a time when the phase of the current wave form with the largest absolute value is changed over to get obtaining control signals, thereby allowing the 3-phase bridge circuit to be PWM switching-controlled.
Inventors:
OONISHI NORIO
Application Number:
JP5219380A
Publication Date:
November 17, 1981
Filing Date:
April 18, 1980
Export Citation:
Assignee:
ONISHI NORIO
International Classes:
H02M7/48; (IPC1-7): H02P13/20
Domestic Patent References:
| JPS55125082A | 1980-09-26 |