| 摘要 |
An apparatus for conversion of a three-phase voltage system into an electrically isolated DC voltage to be predetermined freely, and a method for controlling the same, include primary and secondary circuits. Each phase of the primary circuit has a series inductance connected to one input of a bidirectional, bipolar electronic switching apparatus. Second inputs of the switching apparatuses are directly connected. A positive primary voltage rail is fed through diodes, and a negative primary voltage rail is fed through other diodes. One winding end of a primary winding of a transformer is connected to a line connecting the second inputs of the switching apparatuses. A power transistor, which is connected to the positive primary voltage rail on the collector/drain side and has an antiparallel connected diode, is connected to another winding end of the primary winding. A further power transistor, which is connected to the negative primary voltage rail on the emitter/source side and has an antiparallel connected diode, branches off from the other winding end of the primary winding. A secondary winding of the transformer is connected to input terminals of a single-phase diode bridge having a capacitance disposed between output terminals and smoothing the output voltage as a full-wave bridge circuit.
|
