Power conversion apparatus and charging apparatus

A power conversion apparatus, comprising:

• an alternating current-direct current (AC-DC) conversion circuit;
• a power controller connected to the AC-DC conversion circuit, and the power controller is configured to control the AC-DC conversion circuit to receive an alternating current, convert the alternating current into a first direct current, and output the first direct current;
• and a circulating current controller configured to receive a synchronization signal from another power conversion apparatus through a controller area network (CAN) bus and the synchronization signal is used to synchronize a carrier of the power conversion apparatus with a carrier of the another power conversion apparatus;
• and
• a circulating current detection circuit, the AC-DC conversion circuit comprises a plurality of switches, the circulating current detection circuit is connected to an input end of the AC-DC conversion circuit and the circulating current controller, and the circulating current detection circuit is configured to:
• detect a circulating current value at the input end of the AC-DC conversion circuit, and transmit the circulating current value to the circulating current controller;
• and the circulating current controller is further configured to:
• receive a first modulated wave from the power controller and adjust the first modulated wave based on the circulating current value, to obtain a second modulated wave, the second modulated wave is used to determine a drive signal, and the drive signal is used to control turn-on time of the plurality of switches.

A charging apparatus, comprising a plurality of power conversion apparatuses and a direct current bus, wherein the plurality of power conversion apparatuses are disposed in parallel, and each of the plurality of power conversion apparatuses comprises:

• an alternating current-direct current (AC-DC) conversion circuit;
• a power controller connected to the AC-DC conversion circuit, and the power controller is configured to:
• control the AC-DC conversion circuit to receive an alternating current, convert the alternating current into a first direct current, and output the first direct current through the direct current bus;
• and a circulating current controller;
• the plurality of power conversion apparatuses comprise a primary power conversion apparatus and at least one secondary power conversion apparatus, a circulating current controller of the primary power conversion apparatus is a primary circulating current controller, and a circulating current controller of the secondary power conversion apparatus is a secondary circulating current controller;
• and the primary circulating current controller is configured to:
• send a synchronization signal to the secondary circulating current controller through a controller area network (CAN) bus, and the synchronization signal is used to synchronize a carrier of the secondary power conversion apparatus with a carrier of the primary power conversion apparatus;
• and
• a circulating current detection circuit, the AC-DC conversion circuit comprises a plurality of switches, the circulating current detection circuit is connected to an input end of the AC-DC conversion circuit and the circulating current controller, and the circulating current detection circuit is configured to:
• detect a circulating current value at the input end of the AC-DC conversion circuit and transmit the circulating current value to the circulating current controller;
• and the circulating current controller is configured to:
• receive a first modulated wave from the power controller and adjust the first modulated wave based on the circulating current value, to obtain a second modulated wave, and the second modulated wave is used to determine a drive signal, and the drive signal is used to control turn-on time of the plurality of switches.