| 摘要 |
In a conventional power converting device, control for eliminating or suppressing a beat phenomenon is performed by a control microcomputer. Since computation time is required by the control microcomputer, control delay is generated. Because of the control delay, the effect of fully reducing the pulses of current and torque cannot be obtained. Further, a method for detecting a pulse component using a band-pass filter does not cope with a train in which the frequency of an alternating-current power is switched while the train is running, since a plurality of band-pass filters are required to be provided and switched according to the frequency of the power. A power converting device according to the present invention stores a direct-current voltage value at the predetermined times of sampling from the latest, estimates a direct-current voltage estimation value after the passage of predetermined time from the latest sampling using the stored direct-current voltage value, and controls the amplitude or the frequency of alternating-current power outputted from an inverter using the estimated direct-current voltage estimation value so that the variation of the alternating-current power outputted from the inverter caused by a pulse in the direct current side of the inverter is suppressed. |
