US Patent No. 10,924,024

REGENERATIVE POWER CONVERSION SYSTEM WITH INVERTER AND CONVERTER


Patent No. 10,924,024
Issue Date February 16, 2021
Title Regenerative Power Conversion System With Inverter And Converter
Inventorship Takaaki Norisada, Osaka (JP)
Keiji Akamatsu, Hyogo (JP)
Fumito Kusama, Osaka (JP)
Go Yamada, Osaka (JP)
Yutaka Kamon, Kyoto (JP)
Makoto Ozone, Osaka (JP)
Assignee PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO, LTD., Osaka (JP)

Claim of US Patent No. 10,924,024

1. A power conversion system comprising:a first connection terminal to which a first connection target is connected;
a second connection terminal to which a second connection target is connected;
a primary winding and a secondary winding magnetically coupled to the primary winding;
an inverter circuit connected between the first connection terminal and the primary winding and configured to perform power conversion;
a converter circuit including a plurality of bidirectional switch units; and
a control circuit configured to control the inverter circuit such that polarity of a first voltage across the primary winding alternately inverts,
the secondary winding having a first terminal and a second terminal,
the plurality of bidirectional switch units being bridge-connected between the first terminal and the second terminal of the secondary winding,
the control circuit being configured to control the converter circuit so as to allow no power to be transmitted between the converter circuit and the inverter circuit in a first period including an inversion period during which the first voltage across the primary winding has its polarity inverted,
the control circuit being configured to control the converter circuit so as to allow power to be transmitted either in a first direction from the converter circuit toward the inverter circuit, or in a second direction opposite from the first direction, in a second period different from the first period, wherein
the second connection terminal includes a plurality of terminals associated with the plurality of bidirectional switch units, respectively,
each of the plurality of bidirectional switch units includes a first bidirectional switch unit which is connected to the first terminal of the secondary winding and a second bidirectional switch unit which is connected between the first bidirectional switch unit and the second terminal of the secondary winding,
a node of the first bidirectional switch unit and the second bidirectional switch unit which are included in each of the plurality of bidirectional switch units is connected to one of the plurality of terminals associated with the each of the plurality of bidirectional switch units,
the control circuit is configured to control amplitude of at least one of an output voltage or an output current of the second connection terminal by shifting a first timing and a second timing,
the first timing is a timing when, in a positive polarity period during which the secondary winding has a positive voltage, the converter circuit changes from a first state where a first current flows through the second bidirectional switch units into a second state where a second current flows through the first bidirectional switch units,
the second timing is a timing when, in a negative polarity period which follows the positive polarity period and during which the secondary winding has a negative voltage, the converter circuit changes from the second state where the second current flows through the first bidirectional switch units into the first state where the first current flows through the second bidirectional switch units,
the first bidirectional switch units and the second bidirectional switch units each include a first switch unit and a second switch unit connected to the first switch unit in series,
the control circuit is configured to:
turn the first switch unit of any one of the second bidirectional switch units from ON to OFF when a first predetermined period passes, during the positive polarity period, since the control circuit has turned the first switch unit of a corresponding one of the first bidirectional switch units from OFF to ON;
turn the second switch unit of the second bidirectional switch unit from ON to OFF when a second predetermined period passes, during the positive polarity period, since the control circuit has turned the second switch unit of the first bidirectional switch unit from OFF to ON;
turn the first switch unit of the first bidirectional switch unit from ON to OFF when a third predetermined period passes, during the negative polarity period, since the control circuit has turned the first switch unit of the second bidirectional switch unit from OFF to ON; and
turn the second switch unit of the first bidirectional switch unit from ON to OFF when a fourth predetermined period passes, during the negative polarity period, since the control circuit has turned the second switch unit of the second bidirectional switch unit from OFF to ON.