| 摘要 |
<p>(U.S. 944,608) A converter includes a full-wave bridge network across which operating voltages of +E and -E volts are applied, diagonal legs of the bridge each including two semiconductor switches connected in series between individual operating voltage and output terminals, two diodes polarized in one direction being connected for conducting current from a point of reference potential to the centralmost switches of the two upper legs respectively, and another two diodes like polarized in another direction being connected for conducting current from the centralmost switches of the two lower legs, respectively, to the point of reference potential. Each diode and its associated switch form a unidirectional gated current path and the vertically opposingcentralmost switch and diode pairs of the upper and lower legs form a bidirectional gated current path. The switches are operable for providing zero, +E, +2E, -E and -2E volts across a load in some predetermined sequence for producing a desired AC voltage waveform across the load. The diodes also serve to clamp the common connections between their associated two semiconductor swithces to within a diode drop of the reference potential, thereby protecting the switches from overvoltage.</p> |
