CONTROL DEVICE OF NEUTRAL-POINT-CLAMPED POWER CONVERTER APPARATUS, AND CONTROL METHOD OF NEUTRAL-POINT-CLAMPED POWER CONVERTER APPARATUS

摘要

According to one embodiment, there is provided a control device of a neutral-point-clamped power converter apparatus including a converter configured to convert current which were obtained by passing a d-axis current and a q-axis current of a rotating coordinate system through a filter having a time constant which is greater than an inverse number of a fundamental wave frequency of a three-phase currents, to three-phase currents, and a controller configured to calculate, based on the three-phase currents converted, a zero-phase voltage instruction value for controlling voltages into which a DC input voltage is divided at a neutral point, as an instruction value which is superimposed on three-phase voltage instruction values.

主权项

1. A control device of a neutral-point-clamped power converter apparatus, comprising:
a 3-phase/2-phase converter configured to convert three-phase currents flowing to three-phase loads, which are driven by the neutral-point-clamped power converter apparatus that is connected to a DC power supply having three potentials and is capable of outputting voltages of three levels, to a d-axis current and a q-axis current of a rotating coordinate system; a 2-phase/3-phase current converter configured to convert a d-axis filter current and a q-axis filter current, which were obtained by passing the d-axis current and the q-axis current through a filter having a time constant which is greater than an inverse number of a fundamental wave frequency of the three-phase currents, to three-phase currents; and a neutral-point potential controller configured to calculate, based on the three-phase currents converted by the 2-phase/3-phase current converter, a zero-phase voltage instruction value for controlling voltages into which a DC input voltage is divided at a neutral point of the power converter apparatus, as an instruction value which is superimposed on three-phase voltage instruction values for the power converter apparatus.