| 摘要 |
PROBLEM TO BE SOLVED: To give duties equivalently to actual operation for switching elements by setting an arbitrary phase to a switching state under a specified operating condition, specifying the current phase of the remaining one phase as with respect to the voltage of this phase, and performing phase and amplitude adjustments. SOLUTION: A first phase voltage reference value is set to a rated operating condition, and the phase of a second phase voltage reference value is caused to lead an output line voltage by 90 deg. with respect to the first phase voltage reference value. As a result of this, the phase of a current flowing in a reactor 3 is delayed by 90 deg. with respect to the output line voltage, and becomes the same as that of the first phase voltage reference value. This is the same as the state of outputting an effective power as seen from the first phase switching elements, and a current having a specified current waveform flows in the first phase switching elements. As a result, it is possible to obtain a similar effect to a self-excited converter of single phase bridge configuration, and to perform a test giving duties equivalent to an actual operating condition to the switching elements with the same power as usual. |
