AC/DC CONVERTER HAVING STEP-UP/STEP-DOWN CONVERTER PHASE MODULES

摘要

The invention relates to a converter for transmitting electrical energy between a direct current voltage (DC) system and an alternating current voltage system, comprising a positive DC input voltage rail (1) and a negative DC input voltage rail (2) on the DC voltage side and at least two output phase connections (a, b, c) on the AC voltage side. For each of the output phase connections (a, b, c) there is a phase converter (10a, 10b, 10c), which is connected to the positive DC input voltage rail (1) and the negative DC input voltage rail (2) on a first side, and to said out put phase connection (a; b; c) on a second side, and is designed as a step-up/step-down converter. The converter has a controller which is designed such that, during the operation of the converter, said controller operates each of the phase converters (10a, 10b, 10c) periodically either purely as a step-down converter or purely as a step-up converter, according to a relationship of a DC input voltage relative to instantaneous values of output phase voltages to be generated at the output phase connections (a, b, c).