# US 12,003,107 B2 · Method and apparatus for storing and depleting energy > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,107 B2 - Document ID: US12003107B2 - Status: Granted - Kind: B2 - Application number: 17/885,177 - Filed: 2022-08-10 - Published: 2022-12-08 - Granted: 2024-06-04 - Earliest claimed: 2013-03-14 - Assignees: Solaredge Technologies Ltd. - Applicants: Solaredge Technologies Ltd. - Inventors: Meir Gazit - Web page: https://patentgrep.com/patent/US12003107B2 ## CPC - H02J 3/32: using batteries or super capacitors with converting means - H02J 7/00: Circuit arrangements for charging or discharging batteries or for supplying loads from batteries - H02J 7/02: for charging batteries from AC mains by converters - H02J 7/50: acting upon multiple batteries simultaneously or sequentially - H02J 7/56: Active balancing, e.g. using capacitor-based, inductor-based or DC-DC converters - H02J 7/865: {Battery or charger load switching, e.g. concurrent charging and load supply (H02J7/50 takes precedence)} - H02J 7/92: with prioritisation of loads or sources - H02M 3/1582: {Buck-boost converters (H02M3/1584 takes precedence)} - H02M 7/217: using semiconductor devices only - H02J 7/585: {Sequential battery discharge in systems with a plurality of batteries} - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - 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) ## Abstract A method to control storage into and depletion from multiple energy storage devices. The method enables an operative connection between the energy storage devices and respective power converters. The energy storage devices are connectible across respective first terminals of the power converters. At the second terminals of the power converter, a common reference is set which may be a current reference or a voltage reference. An energy storage fraction is determined respectively for the energy storage devices. A voltage conversion ratio is maintained individually based on the energy storage fraction. The energy storage devices are stored individually with multiple variable rates of energy storage through the first terminals. The energy storage is complete for the energy storage devices substantially at a common end time responsive to the common reference. ## Claims ### Claim 1 A method comprising: transferring, using a plurality of power converters in a first mode and a second mode, power between a plurality of energy storage devices and an electrical network, wherein each power converter of the plurality of power converters is respectively coupled to an energy storage device of the plurality of energy storage devices, and output terminals of the plurality of the power converters are coupled to form a series string; wherein the transferring in the first mode comprises: each power converter, of the plurality of power converters, discharging its respectively coupled energy storage device based on a state of charge of its respectively coupled energy storage device relative to a state of charge of another energy storage device of the plurality of energy storage devices; wherein the transferring in the second mode comprises: each power converter, of the plurality of power converters, charging its respectively coupled energy storage device based on the state of charge of its respectively coupled energy storage device relative to the state of charge of the another energy storage device; and wherein the transferring in the first mode further comprises: each power converter, of the plurality of power converters, maintaining a voltage conversion ratio based on a battery charge fraction of its respectively coupled energy storage device. ### Claim 2 (depends on 1) The method of claim 1, wherein the transferring in the first mode further comprises: a first power converter, of the plurality of power converters, discharging its respectively coupled energy storage device by: determining that the state of charge of its respectively coupled energy storage device is higher than the state of charge of a second energy storage device of the plurality of energy storage devices; and discharging its respectively coupled energy storage device at a first discharge rate; and a second power converter, of the plurality of power converters, discharging the second energy storage device at a second discharge rate lower than the first discharge rate. ### Claim 3 (depends on 1) The method of claim 1, wherein the transferring in the second mode further comprises: a first power converter, of the plurality of power converters, charging its respectively coupled energy storage device by: determining that the state of charge of its respectively coupled energy storage device is higher than the state of charge of a second energy storage device of the plurality of energy storage devices; and charging its respectively coupled energy storage device at a first charge rate; and a second power converter, of the plurality of power converters, charging the second energy storage device at a second charge rate higher than the first charge rate. ### Claim 4 (depends on 1) The method of claim 1, wherein the transferring in the second mode further comprises maintaining, by each power converter of the plurality of power converters and based on the battery charge fraction of its respectively coupled energy storage device, a second voltage conversion ratio. ### Claim 5 (depends on 1) The method of claim 1, wherein the transferring in the first mode and the second mode is further based on a common current reference provided to the plurality of power converters. ### Claim 6 (depends on 1) The method of claim 1, further comprising setting, by a central controller and during the transferring in the first mode, a discharge rate for each power converter of the plurality of power converters. ### Claim 7 (depends on 1) The method of claim 1, further comprising setting, by a central controller and during the transferring in the second mode, a charge rate for each power converter of the plurality of power converters. ### Claim 8 (depends on 1) The method of claim 1, further comprising regulating, by a central controller, a total voltage across the series string. ### Claim 9 (depends on 1) The method of claim 1, further comprising fixing, by a central controller, a total voltage, across the series string, to a predetermined value. ### Claim 10 (depends on 1) The method of claim 1, wherein the transferring in the first mode further comprises each power converter, of the plurality of power converters, being in a buck mode or a boost mode. ### Claim 11 (depends on 1) The method of claim 1, wherein the transferring in the second mode further comprises each power converter, of the plurality of power converters, being in a buck mode or a boost mode. ### Claim 12 (depends on 1) The method of claim 1, wherein the transferring in the first mode or the second mode comprises each power converter, of the plurality of power converters, being in a cascaded buck plus boost mode. ### Claim 13 (depends on 1) The method of claim 1, wherein the each power converter, of the plurality of power converters, comprises a non-isolating power converter. ### Claim 14 (depends on 1) The method of claim 1, further comprising: regulating a first total voltage across the series string and a second total voltage across a second series string, wherein the second series string comprises a second plurality of power converters, and wherein each power converter, of the second plurality of power converters, is respectively coupled to an energy storage device of a second plurality of energy storage devices, and wherein the second plurality of power converters are non-isolating power converters; providing a first current reference signal to each power converter of the plurality of power converters; and providing a second current reference signal to each power converter of the second plurality of power converters. ### Claim 15 (depends on 1) The method of claim 1, wherein the transferring in the first mode further comprises: each power converter, of the plurality of power converters, discharging its respectively coupled energy storage device based on the state of charge of its respectively coupled energy storage device relative to states of charge of all other energy storage devices of the plurality of energy storage devices and wherein the transferring in the second mode further comprises: each power converter, of the plurality of power converters, charging its respectively coupled energy storage device based on the state of charge of its respectively coupled energy storage device relative to the states of charge of the all other energy storage devices. ### Claim 16 A system comprising: a plurality of energy storage devices; and a plurality of power converters, wherein output terminals of the plurality of the power converters are coupled to form a series string, and wherein each power converter, of the plurality of power converters, is: respectively coupled to an energy storage device of the plurality of energy storage devices; configured, in a first mode, to discharge power from its respectively coupled energy storage device based on a state of charge of its respectively coupled energy storage device relative to a state of charge of another energy storage device of the plurality of energy storage devices; configured, in a second mode, to charge its respectively coupled energy storage device based on the state of charge of its respectively coupled energy storage device relative to the state of charge of the another energy storage device; and configured to maintain a voltage conversion ratio based on a battery charge fraction of its respectively coupled energy storage device. ### Claim 17 (depends on 16) The system of claim 16, further comprising a central controller configured to: determine that the state of charge of a first energy storage device of the plurality of energy storage devices is higher than a state of charge of a second energy storage device of the plurality of energy storage devices; instruct, based on the determining, a first power converter, respectively coupled to the first energy storage device, to discharge the first energy storage device at a first discharge rate; and instruct, based on the determining, a second power converter, respectively coupled to the second energy storage device, to discharge the second energy storage device at a second discharge rate lower than the first discharge rate. ### Claim 18 (depends on 16) The system of claim 16, further comprising a central controller configured to: determine that a state of charge of a first energy storage device of the plurality of energy storage devices is higher than a state of charge of a second energy storage device of the plurality of energy storage devices; instruct, based on the determining, a first power converter, respectively coupled to the first energy device, to charge the first energy storage device at a first charge rate; and instruct, based on the determining, a second power converter, respectively coupled to the second energy device, to charge the second energy storage device at a second charge rate higher than a first discharge rate. ### Claim 19 (depends on 16) The system of claim 16, wherein each power converter of the plurality of power converters is further configured to transfer power in the first mode and the second mode based on a common current reference provided to the plurality of power converters. ### Claim 20 (depends on 16) The system of claim 16, further comprising a central controller configured to set: in the first mode, a discharge rate for each power converter of the plurality of power converters; and in the second mode, a charge rate for each power converter of the plurality of power converters. ### Claim 21 (depends on 16) The system of claim 16, further comprising a central controller configured to regulate a total voltage across the series string. ### Claim 22 (depends on 16) The system of claim 16, further comprising a central controller configured to fix a total voltage, across the series string, to a predetermined value. ### Claim 23 (depends on 16) The system of claim 16, wherein each power converter, of the plurality of power converters, comprises a buck stage or a boost stage. ### Claim 24 (depends on 16) The system of claim 16, wherein each power converter, of the plurality of power converters, comprises a buck stage coupled in cascade with a boost stage. ### Claim 25 (depends on 16) The system of claim 16, wherein each power converter, of the plurality of power converters, comprises a non-isolating power converter. ### Claim 26 (depends on 16) The system of claim 16, further comprising: a second plurality of energy storage devices; a second plurality of power converters, wherein each power converter, of the second plurality of power converters, is respectively coupled to an energy storage device of the second plurality of energy storage devices, and output terminals of the second plurality of the power converters are coupled to form a second series string, and the second plurality of power converters are non-isolating power converters; and a central controller configured to: regulate a first total voltage across the series string and a second total voltage across a second series string; provide a first current reference signal to each power converter of the plurality of power converters; and provide a second current reference signal to each power converter of the second plurality of power converters. ### Claim 27 (depends on 16) The system of claim 16, wherein, in the first mode, each power converter, of the plurality of power converters, is configured to discharge its respectively coupled energy storage device based on the state of charge of its respectively coupled energy storage device relative to states of charge of all other energy storage devices of the plurality of energy storage devices and wherein, in the second mode, each power converter, of the plurality of power converters, is configured to charge its respectively coupled energy storage device based on the state of charge of its respectively coupled energy storage device relative to the states of charge of the all other energy storage devices.