# US 11,114,882 B2 · Power converter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,114,882 B2 - Document ID: US11114882B2 - Status: Granted - Kind: B2 - Application number: 16/433,422 - Filed: 2019-06-06 - Published: 2020-01-30 - Granted: 2021-09-07 - Earliest claimed: 2018-07-25 - Assignees: Fuji Electric Co., Ltd. - Applicants: Fuji Electric Co., Ltd. - Inventors: Hiroki Muratsu - Web page: https://patentgrep.com/patent/US11114882B2 ## CPC - H02M 7/23: arranged for operation in parallel {(H02M7/2176 takes precedence)} - H02J 7/02: for charging batteries from AC mains by converters - H02J 7/06: using discharge tubes or semiconductor devices - H02J 7/865: {Battery or charger load switching, e.g. concurrent charging and load supply (H02J7/50 takes precedence)} - H02J 9/062: {for AC powered loads} - H02M 3/158: including plural semiconductor devices as final control devices for a single load - H02M 5/4585: {having a rectifier with controlled elements} - H02M 7/219: in a bridge configuration - H02M 7/493: the static converters being arranged for operation in parallel - H02M 7/5387: in a bridge configuration - H02J 7/34: Parallel operation in networks using both storage and other DC sources, e.g. providing buffering (H02J7/14 takes precedence) - H02M 1/007: {Plural converter units in cascade (push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826)} - H02M 1/08: Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters - H02M 7/487: Neutral point clamped inverters - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract A power converter includes a plurality of power conversion units connected to one another in parallel, each including an AC/DC converter (rectifier) that converts AC power from an AC input power supply (commercial power supply) into DC power, a DC/DC converter (DC power converter) that converts the DC power from the AC/DC converter, and a current detector that detects charge current flowing from the DC/DC converter as well as discharge current flowing to the DC/DC converter. The power converter further includes a battery (electrical storage unit) that is charged by a subset of DC/DC converters among the DC/DC converters of the plurality of power conversion units, as well as a CPU (controller) that controls the DC/DC converters of the plurality of power conversion units. ## Claims ### Claim 1 A power converter, comprising: an electrical storage unit; a plurality of power conversion units connected to one another in parallel, each of the power conversion units including: a rectifier that converts AC power from a commercial power supply into DC power, a DC power converter that is connected to the rectifier on one end and connected to the electrical storage unit on another end and that converts the DC power from the rectifier when charging the electrical storage unit and converts DC power from the electrical storage unit when discharging the electrical storage unit, and a current detector that detects charge current that flows from the DC power converter to the electrical storage unit as well as discharge current that flows to the DC power converter from the electrical storage unit; and a controller that controls the respective DC power converters of the plurality of power conversion units such that when charging the electrical storage unit, only a subset of the DC power converters, not all of the DC power converters, among the respective DC power converters of the power conversion units charges the electrical storage unit, wherein each of the plurality of power conversion units further includes an AC power converter that converts the DC power from the rectifier or DC power from the DC converter when the electrical storage unit is discharging into AC power and supplies the AC power to a load, and wherein the controller changes a number of active DC power converters in the subset when charging the electrical storage unit on the basis of current flowing from the AC power converters to the load. ### Claim 2 (depends on 1) The power converter according to claim 1, wherein when discharging from the electrical storage unit, the controller activates all of the DC power converters of the plurality of power conversion units. ### Claim 3 (depends on 1) A power converter according to claim 1, comprising: an electrical storage unit; a plurality of power conversion units connected to one another in parallel, each of the power conversion units including: a rectifier that converts AC power from a commercial power supply into DC power, a DC power converter that is connected to the rectifier on one end and connected to the electrical storage unit on another end and that converts the DC power from the rectifier when charging the electrical storage unit and converts DC power from the electrical storage unit when discharging the electrical storage unit, and a current detector that detects charge current that flows from the DC power converter to the electrical storage unit as well as discharge current that flows to the DC power converter from the electrical storage unit; and a controller that controls the respective DC power converters of the plurality of power conversion units such that when charging the electrical storage unit, only a subset of the DC power converters, not all of the DC power converters, among the respective DC power converters of the power conversion units charges the electrical storage unit, wherein the controller changes a number of active DC power converters in the subset for charging the electrical storage unit on the basis of the charging current value detected by the current detectors. ### Claim 4 A power converter, comprising: an electrical storage unit; a plurality of power conversion units connected to one another in parallel, each of the power conversion units including: a rectifier that converts AC power from a commercial power supply into DC power, a DC power converter that is connected to the rectifier on one end and connected to the electrical storage unit on another end and that converts the DC power from the rectifier when charging the electrical storage unit and converts DC power from the electrical storage unit when discharging the electrical storage unit, and a current detector that detects charge current that flows from the DC power converter to the electrical storage unit as well as discharge current that flows to the DC power converter from the electrical storage unit; and a controller that controls the respective DC power converters of the plurality of power conversion units such that when charging the electrical storage unit, only a subset of the DC power converters, not all of the DC power converters, among the respective DC power converters of the power conversion units charges the electrical storage unit, wherein the controller selects the DC power converters in the subset that charges the electrical storage unit based on priority rankings that are assigned to the respective DC power converters of the plurality of power conversion units. ### Claim 5 (depends on 4) The power converter according to claim 4, wherein the priority rankings used to select the DC power converters in the subset from among the DC power converters of the plurality of power conversion units are updated each time a prescribed period of time elapses. ### Claim 6 (depends on 4) The power converter according to claim 4, wherein the controller determines the priority rankings on the basis of cumulative operation times of the DC power converters or temperatures of cooling air that cools the DC power converters. ### Claim 7 (depends on 3) The power converter according to claim 3, wherein when discharging from the electrical storage unit, the controller activates all of the DC power converters of the plurality of power conversion units. ### Claim 8 (depends on 3) The power converter according to claim 3, wherein the controller selects the DC power converters in the subset that charges the electrical storage unit based on priority rankings that are assigned to the respective DC power converters of the plurality of power conversion units. ### Claim 9 (depends on 8) The power converter according to claim 8, wherein the priority rankings used to select the DC power converters in the subset from among the DC power converters of the plurality of power conversion units are updated each time a prescribed period of time elapses. ### Claim 10 (depends on 8) The power converter according to claim 8, wherein the controller determines the priority rankings on the basis of cumulative operation times of the DC power converters or temperatures of cooling air that cools the DC power converters. ### Claim 11 (depends on 4) The power converter according to claim 4, wherein when discharging from the electrical storage unit, the controller activates all of the DC power converters of the plurality of power conversion units. ### Claim 12 (depends on 4) The power converter according to claim 4, wherein each of the plurality of power conversion units further includes an AC power converter that converts the DC power from the rectifier or DC power from the DC converter when the electrical storage unit is discharging into AC power and supplies the AC power to a load, and wherein the controller changes a number of active DC power converters in the subset when charging the electrical storage unit on the basis of current flowing from the AC power converters to the load. ### Claim 13 (depends on 1) The power converter according to claim 1, wherein the controller selects the DC power converters in the subset that charges the electrical storage unit based on priority rankings that are assigned to the respective DC power converters of the plurality of power conversion units, and wherein the priority rankings used to select the DC power converters in the subset from among the DC power converters of the plurality of power conversion units are updated each time a prescribed period of time elapses. ### Claim 14 (depends on 1) The power converter according to claim 1, wherein the controller selects the DC power converters in the subset that charges the electrical storage unit based on priority rankings that are assigned to the respective DC power converters of the plurality of power conversion units, and wherein the controller determines the priority rankings on the basis of cumulative operation times of the DC power converters or temperatures of cooling air that cools the DC power converters.