Power supply system and power supply unit
Provided is a power supply system in which two or more power supply units are optionally connected and used in any operation mode. The present invention includes a power supply main circuit 30 that converts AC power 21 into DC power; a current detection unit 302 that detects an output current Io; a voltage detection unit 301 that detects an output voltage Vo; a parameter storage unit 34 that rewritably holds, as a target value Cr, operation mode information Cm selectively indicating constant current operation or constant voltage operation, and one of a target current Iref and a target voltage Vref corresponding to the operation mode information Cm; a control unit 36 that controls the power supply main circuit 30 such that one of the output current Io and the output voltage Vo corresponding to operation mode information Cm matches the target value Cr; a balance information transmission unit 32 that transmits the other of the output current Io and the output voltage Vo as balance information Bi; and a balance information reception unit 32 that receives, as balance information Bi, the other of the output current Io and the output voltage Vo from another one of the power supply units, in which the control unit 36 controls the power supply main circuit 30 based on balance information Bi of the own unit and of the another power supply unit and performs balance adjustment with the another power supply unit.
1 . A power supply system that includes two or more optionally connectable power supply units, the power supply units cooperating to supply DC power to a shared load,
wherein each of the power supply units includes:
a power supply main circuit that converts AC power supplied from a power grid into DC power;
a current detection unit that detects an output current;
a voltage detection unit that detects an output voltage;
a parameter storage unit that rewritably holds, as a target value, operation mode information selectively indicating constant current mode or constant voltage mode, and one of a target current or a target voltage, whichever corresponds to the operation mode information;
a control unit that controls the power supply main circuit such that one of the output current or the output voltage, whichever corresponds to the operation mode information, matches the target value;
a balance information transmission unit that transmits, as balance information, the output voltage when the operation mode information indicates the constant current mode in case of series connection of the power supply units and the output current when the operation mode information indicates the constant voltage mode in case of parallel connection of the power supply units; and
a balance information reception unit that receives, as balance information, the output voltage when the operation mode information indicates the constant current mode in case of series connection of the power supply units and the output current when the operation mode information indicates the constant voltage mode in case of parallel connection of the power supply units from another one of the power supply units, and
wherein the control unit performs balance adjustment with the another power supply unit by controlling the power supply main circuit to operate from beginning to end of the balance adjustment in either the constant current mode or the constant voltage mode indicated by the balance information of an own unit and the another power supply unit based on a difference between the output voltage of the own unit and an average of the output voltage of the another power supply unit in case of the constant current mode and a difference between the output current of the own unit and an average of the output current of the another power supply unit in case of the constant voltage mode.
2 . The power supply system according to claim 1 ,
wherein the parameter storage unit rewritably holds balance adjustment target information for identifying the another power supply unit serving as a reference target for balance adjustment,
wherein the balance information transmission unit transmits balance information on the own unit to an inter-unit communication line of a bus communication type, and
wherein the balance information reception unit selectively receives the balance information from the inter-unit communication line based on the balance adjustment target information.
3 . The power supply system according to claim 2 , wherein another power supply unit connected in series to the own unit is set as the reference target for the balance adjustment during the constant current mode, whereas, during the constant voltage mode, another power supply unit connected in parallel to the own unit is set as the reference target for the balance adjustment.
4 . The power supply system according to claim 2 , wherein the balance adjustment target information is generated by a control terminal based on a user operation and transmitted to the power supply units.
5 . A power supply unit connected in series or in parallel with another power supply unit, the power supply unit cooperating with the another power supply unit to supply DC power to a shared load, the power supply unit comprising:
a power supply main circuit that converts AC power supplied from a power grid into DC power;
a current detection unit that detects an output current;
a voltage detection unit that detects an output voltage;
a parameter storage unit that rewritably holds, as a target value, operation mode information selectively indicating constant current mode or constant voltage mode, and one of a target current or a target voltage, whichever corresponds to the operation mode information;
a control unit that controls the power supply main circuit such that one of the output current or the output voltage, whichever corresponds to the operation mode information, matches the target value;
a balance information transmission unit that, as balance information, the output voltage when the operation mode information indicates the constant current mode in case of series connection of the power supply unit and the another power supply unit and the output current when the operation mode information indicates the constant voltage mode in case of parallel connection of the power supply unit and the another power supply unit; and
a balance information reception unit that receives, as balance information, the output voltage when the operation mode information indicates the constant current mode in case of series connection of the power supply unit and the another power supply unit and the output current when the operation mode information indicates the constant voltage mode in case of parallel connection of the power supply unit and the another power supply unit, from the another power supply unit, and
wherein the control unit performs balance adjustment with the another power supply unit by controlling the power supply main circuit to operate from beginning to end of the balance adjustment in either the constant current mode or the constant voltage mode indicated by the balance information of an own unit and the another power supply unit based on a difference between the output voltage of the own unit and an average of the output voltage of the another power supply unit in case of the constant current mode and a difference between the output current of the own unit and an average of the output current of the another power supply unit in case of the constant voltage mode.