ELECTRIC POWER CONVERSION DEVICE

摘要

An electric power conversion device has a transformer, a DC-AC conversion circuit, an AC-DC conversion circuit and a control circuit. The control circuit calculates an input current instruction value Iref based on a difference value ΔV between an output voltage Vout of the AC-DC conversion circuit and an output voltage instruction value Vref. A comparator compares an input current Iin of the DC-AC conversion circuit with the value Iref. The DC-AC conversion circuit is controlled by the comparison result of the comparator. The control circuit correctly determines an occurrence of an abnormality state of the electric power conversion device based on the operation state of the comparator, the difference value ΔV between the output voltage Vout of the AC-DC conversion circuit and the output voltage instruction value Vref, and the input voltage Vin of the DC-AC conversion circuit without using any output current of the AC-DC conversion circuit.

主权项

1. An electric power conversion device comprising:
a transformer comprising a primary winding and secondary windings; a direct current-alternating current conversion circuit connected to the primary winding, configured to receive an input current and convert the received input current to an alternating current, and supply the alternating current to the primary winding of the transformer; an alternating current-direct current conversion circuit connected to the secondary windings, configured to receive an alternating current supplied from the secondary windings, and convert the received alternating current to a direct current, and output the direct current; and a control circuit comprising a comparator, configured to calculate an input current instruction value on the basis of a difference between an output voltage of the alternating current-direct current conversion circuit and an output voltage instruction value, the comparator configured to compare the input current with the input current instruction value, and the control circuit configured to control operation of the direct current-alternating current conversion circuit, wherein the control circuit determines an occurrence of an abnormality state of the electric power conversion device on the basis of a comparison result of the comparator and the difference between the output voltage of the alternating current-direct current conversion circuit and the output voltage instruction value.