| 摘要 |
<p>PURPOSE:To get rid of bad effect on load with an improved output voltage accuracy by reducing imbalance of 3-phase output voltage when the proportion of the single- phase load increases in 3-phase output. CONSTITUTION:2 and 3-phase output unbalance is reduced with respect to single phase loads 1 and 2 within the self-sufficient range of power by a Scott connection type 3 phase 2 phase conversion transformer 13. When one of power converters breaks down, a load contacts 10 is released on the side of trouble to turn on a change-over contactor 12 whereby power is fed in extension from a power converter on the sound side to the trouble side. That is, route of U phase W phase, V phase U phase and W phase V phase is established. This makes it possible to hold 3-phase unbalance less than the normal level when single loads 1 and 2 of 2 units are viewed from the power converter.</p> |
