# US 2020/0401175 A1 · Constant voltage dc supply device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0401175 A1 - Document ID: US20200401175A1 - Status: Published application - Kind: A1 - Application number: 16/979,142 - Filed: 2019-02-26 - Published: 2020-12-24 - Earliest claimed: 2018-03-12 - Assignees: Takashi Kamezawa; Yoshio Takimoto; Akihiko Tanaka - Inventors: Takashi KAMEZAWA; Akihiko TANAKA; Masaki SAKAGUCHI - Web page: https://patentgrep.com/patent/US20200401175A1 ## CPC - G05F 1/577: for plural loads - H02J 7/34: Parallel operation in networks using both storage and other DC sources, e.g. providing buffering (H02J7/14 takes precedence) - H02J 7/342: {The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging (with circuits for polarity protection H02J7/68)} - H02J 7/35: with light sensitive cells - H02J 7/585: {Sequential battery discharge in systems with a plurality of batteries} - H02J 2207/50: Charging of capacitors, supercapacitors, ultra-capacitors or double layer capacitors - Y02T 10/70: Energy storage systems for electromobility, e.g. batteries - G05F: SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract To provide a constant voltage DC supply device capable of supplying a direct current at a predetermined voltage for a long time irrespective of characteristics of a storage battery and the like. The constant voltage DC supply device for supplying a direct current at a predetermined voltage from a specific power generation unit, including: a plurality of power storage units 10a, 10b; a drive units 30 that is connected to the power storage units and rotating/driving by power supplied from any one of the power storage units; a plurality of the power generation units 40a, 40b connected to the drive units, respectively, and generating power by driving of the drive units; and a control unit 30 for controlling connection between the plurality of power storage units and the driving unit and between the power generation units other than the specific power generation unit 40b and the power storage units 40a, in which wherein the control unit executes control such that, when a voltage of the power storage unit supplying the power to the drive unit falls to a first voltage or less, the power is supplied from the power storage unit other than power storage part and to charge at least one power storage part other than that power storage unit is charged. ## Claims ### Claim 1 A constant voltage DC supply device for supplying a direct current at a predetermined voltage from a specific power generation unit, comprising: a plurality of power storage units; a drive unit connected to the plurality of power storage units and rotating/driving by power supplied from any one of the power storage units; a plurality of the power generation units connected to the drive units, respectively, and generating power by driving of the drive units; and a control unit for controlling connection between the plurality of power storage units and the driving unit and between the power generation units other than the specific power generation unit and the power storage units, wherein the control unit executes control such that, when a voltage of one power storage unit supplying the power to the drive unit falls to a first voltage or less, the power is supplied from the power storage unit other than the one power storage unit and that at least one power storage unit other than the one power storage unit is charged. ### Claim 2 (depends on 1) The constant voltage DC supply device according to claim 1, wherein the constant voltage DC supply device is composed of the drive unit and the power generation unit, capable of charging such that a voltage of the power storage unit to be charged becomes the first voltage or more before the voltage of the power storage unit supplying the power to the drive unit falls below the first voltage. ### Claim 3 (depends on 1) The constant voltage DC supply device according to claim 1, wherein at least one of the power generation units is connected to the drive unit through a converter which converts a torque of the drive unit. ### Claim 4 (depends on 1) The constant voltage DC supply device according to any one of claim 1, wherein the control unit executes control such that, when the voltage of one power storage unit being charged becomes a second voltage higher than the first voltage or more, the power storage unit other than the one power storage unit and other than the power storage unit supplying the power is charged or charging to the one power storage unit is stopped. ### Claim 5 (depends on 1) The constant voltage DC supply device according to any one of claim 1, wherein at least a part of the power storage unit is covered with a heat insulating material. ### Claim 6 (depends on 1) The constant voltage DC supply device according to any one of claim 1, wherein the predetermined voltage is 40 V or more. ### Claim 7 (depends on 2) The constant voltage DC supply device according to claim 2, wherein the control unit executes control such that, when the voltage of one power storage unit being charged becomes a second voltage higher than the first voltage or more, the power storage unit other than the one power storage unit and other than the power storage unit supplying the power is charged or charging to the one power storage unit is stopped.