CN115395605A - Method for improving capacity utilization rate of high-voltage direct-hanging battery energy storage system - Google Patents

Method for improving capacity utilization rate of high-voltage direct-hanging battery energy storage system Download PDF

Info

Publication number
CN115395605A
CN115395605A CN202211027190.7A CN202211027190A CN115395605A CN 115395605 A CN115395605 A CN 115395605A CN 202211027190 A CN202211027190 A CN 202211027190A CN 115395605 A CN115395605 A CN 115395605A
Authority
CN
China
Prior art keywords
battery
discharge
maintenance
charging
deep
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202211027190.7A
Other languages
Chinese (zh)
Other versions
CN115395605B (en
Inventor
蔡旭
吴西奇
李睿
刘畅
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Jiaotong University
Original Assignee
Shanghai Jiaotong University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Jiaotong University filed Critical Shanghai Jiaotong University
Priority to CN202211027190.7A priority Critical patent/CN115395605B/en
Publication of CN115395605A publication Critical patent/CN115395605A/en
Application granted granted Critical
Publication of CN115395605B publication Critical patent/CN115395605B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0047—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with monitoring or indicating devices or circuits
    • H02J7/0048—Detection of remaining charge capacity or state of charge [SOC]
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/385—Arrangements for measuring battery or accumulator variables
    • G01R31/387—Determining ampere-hour charge capacity or SoC
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/28—Arrangements for balancing of the load in a network by storage of energy
    • H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
    • H02J7/0014—Circuits for equalisation of charge between batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)

Abstract

The invention provides a method for improving the capacity utilization rate of a high-voltage direct-hanging battery energy storage system, which comprises the following steps: step A1: starting a high-voltage direct-hanging battery energy storage system based on deep discharge according to the system running state and a maintenance instruction, and performing capacity utilization rate improvement control; step A2: reducing the discharge power of the system according to the discharge degree of the battery cluster, and finally stopping discharging and operating the system under a pure reactive working condition; step A3: and sequentially carrying out deep maintenance and charge state algorithm discharge correction on each battery cluster according to the charge state of the battery cluster. By the method, all the battery clusters of the high-voltage direct-hanging battery energy storage system can be subjected to deep charging and deep discharging maintenance, the battery cluster state-of-charge evaluation algorithm can be corrected, the problem of insufficient system capacity utilization caused by inaccurate evaluation of the state-of-charge of a single battery cluster is solved, and the capacity utilization rate of the high-voltage direct-hanging battery energy storage system is improved.

Description

Method for improving capacity utilization rate of high-voltage direct-hanging battery energy storage system
Technical Field
The invention relates to the technical field of electric automation equipment, in particular to a method for improving the capacity utilization rate of a high-voltage direct-hanging battery energy storage system. In particular, the invention relates to a method for improving the capacity utilization rate of a high-voltage direct-hung battery energy storage system based on deep discharge, a method for improving the capacity utilization rate of a high-voltage direct-hung battery energy storage system based on deep charge, and a method for improving the capacity utilization rate of a high-voltage direct-hung battery energy storage system based on full charge and full discharge.
Background
The conventional battery energy storage system scheme is limited by the technologies such as battery safety, grouping mode and battery management system, the single machine capacity generally does not exceed 0.5MW, a plurality of battery energy storage systems are connected in parallel to form an energy storage power station with larger capacity, and finally the energy storage power station is connected into a medium-high voltage power grid after being stepped up step by step through a step-up transformer. The battery stack in the energy storage power station based on the conventional battery energy storage system framework has the defects of large inter-cluster circulation, obvious barrel effect, low battery utilization rate, easiness in causing safety problems and the like. In addition, the parallel connection of a plurality of energy storage converters can cause the complex structure of an energy storage power station, the occupied area is large, the parasitic parameter distribution is complex due to the long cable line, the system response time is slow due to the communication delay, and the whole power station control system is complex and difficult to coordinate and control, so that the requirements of building a hundred MW-level and GW-level energy storage power stations in the future are difficult to adapt. Therefore, it is necessary to change the architecture of the energy storage system to meet the challenge of the application of large capacity of energy storage.
The high-voltage direct-hanging battery energy storage system based on the cascaded H-bridge converter has a highly modularized structure, is convenient for capacity expansion and redundancy design, can save a power frequency transformer direct-hanging high-voltage power grid, and can eliminate loss caused by the transformer. The high-capacity battery stack is connected to each H-bridge circuit in a scattered manner by taking a single battery cluster as a unit, so that circulation in battery pushing is avoided, the circulation loss of a system is reduced, and the safety of the system is improved. Compared with the traditional energy storage system, the high-voltage direct-hanging battery energy storage system realizes the large capacity of a single machine, the number of the parallel-connected batteries is small when a large-scale energy storage power station is formed, the occupied area of the power station is reduced, the structure and the control strategy of the power station are simple, the system response speed is high, the problem of system stability is not easily caused, and the requirement for constructing the large-capacity battery energy storage power station can be met.
The battery cluster of the high-voltage direct-hanging battery energy storage system can be subjected to active charge state equalization through each H-bridge circuit, so that the battery capacity utilization rate of the whole battery system is greatly improved compared with that of the traditional energy storage system, however, the system is likely to cause the capacity capable of being charged and discharged to be greatly reduced due to the fact that the battery charge state equalization algorithm of some battery clusters deviates from the actual value, the battery management system is difficult to correct and maintain the battery cluster charge state evaluation algorithm, and the system capacity utilization rate is not high.
Patent document CN211958829U (application number: 202020790485. X) discloses an energy storage battery series-parallel connection equalization control system, which detects the charge state of each battery cell in a battery pack through a charge detection module, detects the voltage value of each battery cell in the battery pack through a voltage detection module, and controls the equalization switch module to open and close to change the series-parallel connection state of the battery pack through a battery management module, so as to equalize the situations of different residual capacities or different voltages of the battery cells, thereby improving the utilization rate of the battery pack and prolonging the service life of the battery pack.
Patent document CN216215976U (application number: 202122524866.0) discloses a rapid balancing device for a battery module of an energy storage system, which can rapidly and effectively complete the capacity balancing of the battery module, complete the field failure maintenance of the battery module, reduce the operation and maintenance cost, and improve the capacity utilization rate of the battery system. The problem that the available capacity of the batteries on the series circuit can only reach the capacity of the weakest battery module, the series mismatch of the battery modules is generated, and the capacity of other batteries cannot be fully utilized is solved, however, the method aims at improving the capacity utilization rate of the battery module level, and the problem of the mismatch of a direct-hanging energy storage system battery cluster cannot be solved.
Patent document CN114336700A (application number: 202111451302.7) discloses a capacity utilization rate control method for a medium-voltage direct-hanging energy storage system, which comprises the following steps: the average value of the voltage of each cluster of upper and lower limit short-plate batteries and the average value of the voltage of each phase of upper and lower limit short-plate batteries are calculated, so that the method is suitable for a balance control method of a medium-voltage direct-hanging type energy storage system which does not depend on an accurate SOC model, and the adaptability and reliability of the model are improved; meanwhile, a novel interphase and intra-phase balance control method for medium-voltage direct-hanging energy storage is provided. The method for globally optimizing the medium-voltage direct-hanging energy storage system improves the effective utilization rate of the system and improves the economy of the system, however, the method completely abandons the control of the battery charge state, and the balance of the battery cluster charge state is difficult to realize in a battery platform area.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a method for improving the capacity utilization rate of a high-voltage direct-hanging battery energy storage system.
The method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep discharge provided by the invention comprises the following steps:
step A1: starting a high-voltage direct-hanging battery energy storage system based on deep discharge according to the system running state and a maintenance instruction, and performing capacity utilization rate improvement control;
Step A2: reducing the discharge power of the system according to the discharge degree of the battery cluster, and finally stopping discharging and operating the system under a pure reactive working condition;
step A3: and sequentially carrying out deep maintenance and charge state algorithm discharge correction on each battery cluster according to the charge state of the battery cluster.
Preferably, the step A1 includes:
step A1.1: when the state of charge of the system is detected to be smaller than a preset threshold value, judging the difference of the open-circuit voltages of the system battery clusters, if the open-circuit voltages of the battery clusters are larger than the discharge protection threshold value and have obvious difference, judging that discharge maintenance is needed, otherwise, judging that the discharge maintenance is not needed;
step A1.2: when detecting that a certain battery cluster reaches a discharge protection threshold, judging the charge state of the system battery cluster and the open-circuit voltages of other battery clusters, if the discharge completion of the charge state of the battery cluster is greater than a preset threshold or the open-circuit voltage of the battery cluster is larger than the relative protection threshold, judging that discharge maintenance is needed, otherwise, judging that the discharge maintenance is not needed;
step A1.3: if the system needs to perform discharge maintenance, judging whether the energy storage system can perform discharge maintenance or not according to the external operating conditions of the system;
step A1.4: and if the system has the maintenance operation condition, starting a capacity utilization rate promotion control algorithm based on deep discharge, simultaneously closing an inter-phase equalization algorithm and an intra-phase equalization algorithm, and then executing the step A2.
Preferably, the step A2 includes:
step A2.1: the system discharges until a battery cluster voltage reaches a discharge three-level alarm value, and reduces the discharge power by half, wherein the discharge three-level alarm value voltage > the discharge two-level alarm value voltage > the discharge one-level alarm value voltage;
step A2.2: after the power is halved, continuing to discharge until the voltage of a battery cluster reaches a discharge three-level alarm value, and halving the discharge power again;
step A2.3: judging whether the discharge power is lower than a discharge power reduction threshold value, if so, keeping the discharge power threshold value to be discharged until a battery cluster voltage reaches a discharge secondary alarm value, marking the battery cluster as deeply-discharged maintenance, correcting the charge state of the battery cluster by a battery management system BMS, recording an x-phase y-th module to which the battery cluster belongs, and marking the x-phase y-th module as M xy ；
Step A2.4: the system stops discharging and the control system operates in a pure reactive working condition.
Preferably, in the step A3:
step A3.1: selecting a z-th module which belongs to the battery cluster without deep maintenance in the x phase and has a notation of M xz ；
Step A3.2: in module M xy A voltage V with amplitude meeting the preset condition and the same phase with the phase current of x is superposed on the modulation wave xy Module M xy Charging the middle battery cluster;
step A3.3: in module M xz Superimposing an amplitude and a voltage V on the modulated wave xy Voltage V in phase opposition to the x-phase current xz ＝V xy Module M xz Discharging the middle battery cluster;
step A3.4: module M xz Discharging until the voltage of the battery cluster reaches a discharging secondary alarm value, and obtaining a module M xy Stopping charging, module M xz Stopping discharging and marking the discharge as deep maintenance, and making y = z, and a module M xz Reset to M xy ；
Step A3.5: judging whether all the x-phase battery clusters complete deep maintenance or not, and returning to the step A3.1 to continue execution if the x-phase battery clusters do not complete deep maintenance; if the x phase is maintained, executing the step A3.6;
step A3.6: judging whether deep maintenance of all the three-phase battery clusters is finished, and if not, executing the step A3.7; if the three phases are completely maintained, the deep maintenance of the whole system is completed;
step A3.7: injecting zero sequence voltage to discharge the non-maintained phase x until the voltage of a battery cluster reaches a discharge secondary alarm value, recording the y-th module of the x phase to which the battery cluster belongs, and the notation is M xy And returning to the step A3.1 to continue the execution.
The method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep charging provided by the invention comprises the following steps:
step B1: starting a high-voltage direct-hanging battery energy storage system based on deep charging according to the system running state and a maintenance instruction, and performing capacity utilization rate improvement control;
And step B2: reducing the charging power of the system according to the charging degree of the battery cluster, and finally stopping charging and operating the system under a pure reactive working condition;
and step B3: and carrying out deep charge maintenance and charge state algorithm charge correction on each battery cluster in sequence according to the charge state of the battery cluster.
Preferably, the step B1 includes:
step B1.1: when the state of charge of the system is detected to be larger than a preset threshold value, judging the difference of the open-circuit voltages of the system battery clusters, if the open-circuit voltages of the battery clusters are larger than the charge protection threshold value and have obvious difference, judging that the charging maintenance is needed, otherwise, judging that the charging maintenance is not needed;
step B1.2: when a certain battery cluster is detected to reach a charging protection threshold, judging the state of charge of the system battery cluster and the open-circuit voltages of other battery clusters, if the state of charge of the battery cluster exceeds a preset range or the open-circuit voltage of the battery cluster is larger than the protection threshold, judging that charging maintenance is needed, otherwise, judging that the charging maintenance is not needed;
step B1.3: if the system needs to be charged and maintained, judging whether the energy storage system can be charged and maintained according to the external operating conditions of the system;
step B1.4: and if the system has the maintenance operation condition, starting a capacity utilization rate promotion control algorithm based on deep charging, simultaneously closing an inter-phase equalization algorithm and an intra-phase equalization algorithm, and then executing the step B2.
Preferably, the step B2 includes:
step B2.1: charging the system until a battery cluster voltage reaches a charging third-level alarm value, and reducing the charging power by half, wherein the charging third-level alarm value voltage is less than the charging second-level alarm value voltage and less than the charging first-level alarm value voltage;
step B2.2: after the power is halved, continuously charging until the voltage of one battery cluster reaches a charging three-level alarm value, and halving the charging power again;
step B2.3: judging whether the charging power is lower than a charging power reduction threshold value, if so, keeping the charging power threshold value charged until a battery cluster voltage reaches a charging secondary alarm value, marking the battery cluster as deeply charged maintenance, correcting the charge state of the battery cluster by a Battery Management System (BMS), recording an x-phase y-th module to which the battery cluster belongs, and marking the x-phase y-th module as M xy ；
Step B2.4: and the system stops charging and controls the system to operate under a pure reactive working condition.
Preferably, the step B3 includes:
step B3.1: selecting a z-th module which belongs to a battery cluster which is not subjected to deep charge maintenance in x phases and is marked as M xz ；
Step B3.2: in module M xy The modulating wave is superposed with a voltage V with amplitude meeting the preset condition and the opposite phase of the x-phase current xy Module M xy Discharging the middle battery cluster;
step B3.3: in module M xz Superimposing an amplitude and a voltage V on the modulated wave xy Voltage V of the same phase as x-phase current xz ＝V xy Module M xz Charging the middle battery cluster;
step B3.4: module M xz Charging until the voltage of the battery cluster reaches a charging secondary alarm value, and performing moduleM xy Stopping charging, module M xz Stopping charging and marking as deep charging maintenance is carried out, making y = z, and obtaining a module M xz Reset to M xy ；
Step B3.5: judging whether all the x-phase battery clusters complete deep charge maintenance or not, and returning to the module M3.1 to continue running if the x-phase battery clusters do not complete deep charge maintenance; if the x phase is maintained, the module M3.6 is operated;
step B3.6: judging whether deep charging maintenance is finished for all the three-phase battery clusters, and if not, operating the module M3.7; if the three phases are completely maintained, the deep charging maintenance of the whole system is completed;
step B3.7: injecting zero sequence voltage to charge the non-maintained phase x until the voltage of a battery cluster reaches a charging secondary alarm value, recording the y-th module of the x phase to which the battery cluster belongs, and the notation is M xy And returning to the module M3.1 to continue running.
The method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on full charge and full discharge provided by the invention comprises the following steps:
if the high-voltage direct-hung battery energy storage system based on deep discharge is started to carry out capacity utilization rate improvement control according to the system operation state and a maintenance instruction, the system operates according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep discharge, after the discharge maintenance is finished, the system recovers normal charge operation until the charge maintenance condition is met, the high-voltage direct-hung battery energy storage system based on deep discharge operates according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep discharge, and after the charge maintenance is finished, the system finishes one-time full charge and full discharge maintenance;
If the high-voltage direct-hung battery energy storage system based on deep charging is started to carry out capacity utilization rate improvement control according to the system operation state and the maintenance instruction, the system operates according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep charging, after charging maintenance is finished, the system recovers normal discharging operation until the discharging maintenance condition is met, the system operates according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep discharging, and after discharging maintenance is finished, the system finishes one-time full-charging full-discharging maintenance.
Compared with the prior art, the invention has the following beneficial effects:
(1) According to the method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep discharge, disclosed by the invention, one-time deep discharge of all battery clusters of the chained battery energy storage system can be realized through the control method, the accuracy of the battery management system in evaluating the charge state of the battery clusters is corrected, and the capacity utilization rate of the system is favorably improved;
(2) According to the method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep charging, the control method can realize one-time deep charging of all battery clusters of the chained battery energy storage system, the accuracy of the battery management system in evaluating the charge state of the battery clusters is corrected, and the capacity utilization rate of the system is improved;
(3) The capacity utilization rate improving method of the high-voltage direct-hanging battery energy storage system based on full charge and full discharge provided by the invention can be used for carrying out one-time full charge and full discharge system maintenance and battery charge state evaluation algorithm correction on all battery clusters, is beneficial to the actual effect of inter-phase and intra-phase equalization algorithms of the battery clusters, and improves the capacity utilization rate of the system.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:
FIG. 1 is a diagram of a high voltage direct-mounted battery energy storage system according to a preferred embodiment of the present invention;
fig. 2 is a control flow diagram of a capacity utilization rate improvement method for a high-voltage direct-hanging battery energy storage system based on deep discharge in a preferred embodiment of the present invention;
fig. 3 is a block diagram of a control flow of a method for improving the capacity utilization of a high-voltage direct-hanging battery energy storage system based on deep charging in a preferred embodiment of the present invention.
Detailed Description
The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the invention.
Example (b):
referring to fig. 1, which is a structural diagram of a high-voltage direct-hanging battery energy storage system in an embodiment of the present invention, the high-voltage direct-hanging battery energy storage system is directly connected to a power grid of each voltage class, and includes: the system comprises an A-phase power module, a B-phase power module and a C-phase power module; each phase is formed by cascading n power modules, each power module mainly comprises an H-bridge power device and a driving circuit thereof, a bus capacitor, a direct current fuse and a battery side pre-charging device, the direct current side of the H-bridge power module is connected with a battery cluster through a high-voltage cable and a direct current side filter inductor, and the cascaded H-bridge converter is directly connected into a medium-high voltage power grid through the filter inductor, the alternating current side pre-charging device and the alternating current fuse at the alternating current side; in the figure v sa 、v sb 、v sc Voltage of three-phase network, v a 、v b 、v c For cascading H-bridge converters output voltage, i a 、i b 、i c Outputting current for the converter.
The method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep discharge, as shown in fig. 2, comprises the following steps:
step A1: starting the capacity utilization rate improvement control of the high-voltage direct-hanging battery energy storage system based on deep discharge according to the system running state and the maintenance instruction;
step A2: reducing the system discharge power according to the battery cluster discharge degree, and finally stopping the system discharge and operating in a pure reactive working condition;
Step A3: and sequentially carrying out deep maintenance and charge state algorithm discharge correction on each battery cluster according to the charge state of the battery cluster.
Specifically, in the step A1:
step A1.1: when the state of charge of the system is detected to be smaller than a certain value, judging the difference of the open-circuit voltages of the system battery clusters, if the open-circuit voltages of the battery clusters are larger than the discharge protection threshold value and have obvious difference, judging that the discharge maintenance is needed, otherwise, judging that the discharge maintenance is not needed;
step A1.2: when a certain battery cluster is detected to reach a discharge protection threshold, judging the charge state of the system battery cluster and the open-circuit voltages of other battery clusters, if the charge state of the battery cluster is relatively large after discharge or the open-circuit voltage of the battery cluster is relatively large relative to the protection threshold, judging that discharge maintenance is needed, otherwise, judging that the discharge maintenance is not needed;
step A1.3: if the system needs to carry out discharge maintenance, judging whether the energy storage system can carry out discharge maintenance or not according to the external operating conditions of the system;
step A1.4: and if the system has the maintenance operation condition, starting a capacity utilization rate promotion control algorithm based on deep discharge, simultaneously closing an inter-phase equalization algorithm and an intra-phase equalization algorithm, and entering the step A2.
Specifically, in the step A2:
step A2.1: when the system discharges until a battery cluster voltage reaches a discharge three-level alarm value (discharge three-level alarm value voltage > discharge two-level alarm value voltage > discharge one-level alarm value voltage), the discharge power is reduced by half;
step A2.2: after the power is halved, continuously discharging until the voltage of one battery cluster reaches a discharge three-level alarm value, and halving the discharge power again;
step A2.3: judging whether the discharge power is lower than a discharge power reduction threshold value, if so, keeping the discharge power threshold value to discharge until a battery cluster voltage reaches a discharge secondary alarm value, marking the battery cluster as deeply-discharged maintenance, correcting the charge state of the battery cluster by the BMS, recording an x-phase y-th module to which the battery cluster belongs, and marking the x-phase y-th module as M xy ；
Step A2.4: the system stops discharging and the control system operates in a pure reactive working condition.
Specifically, in the step A3:
step A3.1: selecting a z-th module which belongs to a battery cluster which is not subjected to deep maintenance in the x phase and is marked as M xz ；
Step A3.2: on the moduleM xy A voltage V with proper amplitude and the same phase with the phase current of the x phase is superposed on the modulation wave xy Module M xy Charging the middle battery cluster;
step A3.3: in module M xz Superimposing an amplitude and a voltage V on the modulated wave xy Voltage V in phase opposition to the x-phase current xz ＝V xy Module M xz Discharging the middle battery cluster;
step A3.4: module M xz Discharging until the voltage of the battery cluster reaches a discharging secondary alarm value, and obtaining a module M xy Stopping charging, module M xz Stopping discharging and marking the discharge as deep maintenance, and making y = z, and a module M xz Reset to M xy ；
Step A3.5: judging whether all the x-phase battery clusters complete deep maintenance or not, and if not, re-executing the M3.1 module; if the x phase is maintained, performing an M3.6 module;
step A3.6: judging whether deep maintenance of all the three-phase battery clusters is finished or not, and if not, performing an M3.7 module; if the three phases are completely maintained, the deep maintenance of the whole system is completed;
step A3.7: injecting zero sequence voltage to make the non-maintained phase x discharge until a battery cluster voltage reaches a discharge secondary alarm value, recording the x-phase y-th module of the battery cluster, and the notation is M xy And the M3.1 module is carried out again.
The method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep charging, as shown in fig. 3, comprises the following steps:
step B1: starting capacity utilization rate improvement control of the high-voltage direct-hanging battery energy storage system based on deep charging according to the system running state and the maintenance instruction;
And step B2: reducing the charging power of the system according to the charging degree of the battery cluster, and finally stopping charging and operating the system under a pure reactive working condition;
and step B3: and carrying out deep charge maintenance and charge state algorithm charge correction on each battery cluster in sequence according to the charge state of the battery cluster.
Specifically, in the step B1:
step B1.1: when the state of charge of the system is detected to be larger than a certain value, judging the difference of the open-circuit voltages of the system battery clusters, if the open-circuit voltages of the battery clusters are larger than the charging protection threshold value and have obvious difference, judging that charging maintenance is needed, otherwise, judging that the charging maintenance is not needed;
step B1.2: when detecting that a certain battery cluster reaches a charging protection threshold, judging the charge state of the system battery cluster and the open-circuit voltages of other battery clusters, if the charge state of the battery cluster is larger than the full charge state or the open-circuit voltage of the battery cluster is larger than the protection threshold, judging that charging maintenance is needed, otherwise, judging that the charging maintenance is not needed;
step B1.3: if the system needs to be charged and maintained, judging whether the energy storage system can be charged and maintained according to the external operating conditions of the system;
step B1.4: and if the system has the maintenance operation condition, starting a capacity utilization rate promotion control algorithm based on deep charging, simultaneously closing an inter-phase equalization algorithm and an intra-phase equalization algorithm, and entering the step B2.
Specifically, in the step B2:
step B2.1: charging the system until a battery cluster voltage reaches a charging third-level alarm value (charging third-level alarm value voltage < charging second-level alarm value voltage < charging first-level alarm value voltage), and halving the charging power;
step B2.2: after the power is halved, continuously charging until the voltage of one battery cluster reaches a charging three-level alarm value, and halving the charging power again;
step B2.3: judging whether the charging power is lower than a charging power reduction threshold value, if so, keeping the charging power threshold value to be charged until a battery cluster voltage reaches a charging secondary alarm value, marking the battery cluster as deeply charged for maintenance, correcting the charge state of the battery cluster by the BMS, recording an x-phase y-th module of the battery cluster, and marking as M xy ；
Step B2.4: the system stops charging and the control system operates in a pure reactive working condition.
Specifically, in the step B3:
step B3.1: selecting a z-th module which belongs to a battery cluster which is not subjected to deep charge maintenance in x phases and is marked as M xz ；
Step B3.2: in module M xy The modulating wave is superposed with a voltage V with proper amplitude and opposite phase to the phase current of x-phase xy Module M xy Discharging the middle battery cluster;
step B3.3: in module M xz Superimposing an amplitude and a voltage V on the modulated wave xy Voltage V of the same phase as x-phase current xz ＝V xy Module M xz Charging the middle battery cluster;
step B3.4: module M xz Charging until the voltage of the battery cluster reaches a charging secondary alarm value, and module M xy Stopping charging, module M xy Stopping charging and marking as deep charging maintenance is carried out, making y = z, and obtaining a module M xz Reset to M xy ；
Step B3.5: judging whether all the x-phase battery clusters complete deep charge maintenance or not, and if not, re-executing the M3.1 module; if the x phase is maintained, performing an M3.6 module;
step B3.6: judging whether deep charging maintenance is completed on all the three-phase battery clusters, and if not, performing an M3.7 module; if the three phases are completely maintained, the deep charging maintenance of the whole system is completed;
step B3.7: injecting zero sequence voltage to charge the non-maintained phase x until the voltage of a battery cluster reaches a charging secondary alarm value, recording the y-th module of the x phase to which the battery cluster belongs, and the notation is M xy And the M3.1 module is carried out again.
The invention provides a method for improving the capacity utilization rate of a high-voltage direct-hanging battery energy storage system based on full charge and full discharge, which comprises the following steps:
if the capacity utilization rate improvement control of the high-voltage direct-hung battery energy storage system based on deep discharge is started according to the system operation state and the maintenance instruction, the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep discharge is operated, after the discharge maintenance is finished, the system recovers the normal charge operation until the charge maintenance condition is met, the system is operated according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep charge, and after the charge maintenance is finished, the system finishes one-time full-charge full-discharge maintenance;
If the capacity utilization rate improvement control of the high-voltage direct-hanging battery energy storage system based on deep charging is started according to the system running state and the maintenance instruction, the system runs according to the capacity utilization rate improvement method of the high-voltage direct-hanging battery energy storage system based on deep charging, after the charging maintenance is completed, the system recovers normal discharging operation until the discharging maintenance condition is met, the system runs according to the capacity utilization rate improvement method of the high-voltage direct-hanging battery energy storage system based on deep discharging, and after the discharging maintenance is completed, the system completes one-time full-charging full-discharging maintenance.
It is known to those skilled in the art that, in addition to implementing the system, apparatus and its various modules provided by the present invention in pure computer readable program code, the system, apparatus and its various modules provided by the present invention can be implemented in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers and the like by completely programming the method steps. Therefore, the system, the device and the modules thereof provided by the present invention can be considered as a hardware component, and the modules included in the system, the device and the modules thereof for implementing various programs can also be considered as structures in the hardware component; modules for performing various functions may also be considered to be both software programs for performing the methods and structures within hardware components.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.

Claims (9)

1. A method for improving the capacity utilization rate of a high-voltage direct-hanging battery energy storage system based on deep discharge is characterized by comprising the following steps:
step A1: starting a high-voltage direct-hanging battery energy storage system based on deep discharge according to the system running state and a maintenance instruction, and performing capacity utilization rate improvement control;
step A2: reducing the system discharge power according to the battery cluster discharge degree, and finally stopping the system discharge and operating in a pure reactive working condition;
step A3: and sequentially carrying out deep maintenance and charge state algorithm discharge correction on each battery cluster according to the charge state of the battery cluster.
2. The method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep discharge according to claim 1, wherein the step A1 comprises the following steps:
step A1.1: when the state of charge of the system is detected to be smaller than a preset threshold value, judging the difference of the open-circuit voltages of the system battery clusters, if the open-circuit voltages of the battery clusters are larger than the discharge protection threshold value and have obvious difference, judging that discharge maintenance is needed, otherwise, judging that the discharge maintenance is not needed;
Step A1.2: when a certain battery cluster is detected to reach a discharge protection threshold, judging the state of charge of the system battery cluster and the open-circuit voltages of other battery clusters, if the state of charge of the battery cluster is greater than a preset threshold after discharge or the open-circuit voltage of the battery cluster is larger than the relative protection threshold, judging that discharge maintenance is needed, otherwise, judging that the discharge maintenance is not needed;
step A1.3: if the system needs to perform discharge maintenance, judging whether the energy storage system can perform discharge maintenance or not according to the external operating conditions of the system;
step A1.4: and if the system has the maintenance operation condition, starting a capacity utilization rate promotion control algorithm based on deep discharge, simultaneously closing an inter-phase equalization algorithm and an intra-phase equalization algorithm, and then executing the step A2.
3. The method for improving the capacity utilization rate of the energy storage system of the deep-discharge-based high-voltage direct-hanging battery according to claim 2, wherein the step A2 comprises the following steps:
step A2.1: the system discharges until a battery cluster voltage reaches a discharge third-level alarm value, and the discharge power is halved, wherein the discharge third-level alarm value voltage is larger than the discharge second-level alarm value voltage and is larger than the discharge first-level alarm value voltage;
step A2.2: after the power is halved, continuing to discharge until the voltage of a battery cluster reaches a discharge three-level alarm value, and halving the discharge power again;
Step A2.3: judging whether the discharge power is lower than a discharge power reduction threshold value, if so, keeping the discharge power threshold value to be discharged until a battery cluster voltage reaches a discharge secondary alarm value, marking the battery cluster as deeply-discharged maintenance, correcting the charge state of the battery cluster by a battery management system BMS, recording an x-phase y-th module to which the battery cluster belongs, and marking the x-phase y-th module as M xy ；
Step A2.4: the system stops discharging and the control system operates in a pure reactive working condition.
4. The method for improving the capacity utilization rate of the energy storage system of the deep-discharge-based high-voltage direct-hanging battery according to claim 3, wherein in the step A3:
step A3.1: selecting a z-th module which belongs to a battery cluster which is not subjected to deep maintenance in the x phase and is marked as M xz ；
Step A3.2: in module M xy A voltage V with amplitude meeting the preset condition and the same phase with the phase current of x is superposed on the modulation wave xy Module M xy Charging the middle battery cluster;
step A3.3: in module M xz Superimposing an amplitude and a voltage V on the modulated wave xy Voltage V in phase opposition to the x-phase current xz ＝V xy Module M xz Discharging the middle battery cluster;
step A3.4: module M xz Discharging until the voltage of the battery cluster reaches a discharging secondary alarm value, and obtaining a module M xy Stopping charging, module M xz Stopping discharging and marking the discharge as deep maintenance, and making y = z, and a module M xz Reset to M xy ；
Step A3.5: judging whether all the x-phase battery clusters complete deep maintenance or not, and returning to the step A3.1 to continue execution if the x-phase battery clusters do not complete deep maintenance; if the x phase is maintained, executing the step A3.6;
step A3.6: judging whether deep maintenance of all the three-phase battery clusters is finished, and if not, executing the step A3.7; if the three phases are completely maintained, the deep maintenance of the whole system is completed;
step A3.7: injecting zero sequence voltage to make the non-maintained phase x discharge until a battery cluster voltage reaches a discharge secondary alarm value, recording the x-phase y-th module of the battery cluster, and the notation is M xy And returning to the step A3.1 to continue the execution.
5. A method for improving the capacity utilization rate of a high-voltage direct-hanging battery energy storage system based on deep charging is characterized by comprising the following steps:
step B1: starting a high-voltage direct-hanging battery energy storage system based on deep charging according to the system running state and a maintenance instruction, and performing capacity utilization rate improvement control;
and step B2: reducing the charging power of the system according to the charging degree of the battery cluster, and finally stopping charging and operating the system under a pure reactive working condition;
and step B3: and carrying out deep charge maintenance and charge state algorithm charge correction on each battery cluster in sequence according to the charge state of the battery cluster.
6. The method for improving the capacity utilization rate of the energy storage system of the high-voltage direct-hanging battery based on the deep charging according to claim 5, wherein the step B1 comprises the following steps:
step B1.1: when the state of charge of the system is detected to be larger than a preset threshold value, judging the difference of the open-circuit voltages of the system battery clusters, if the open-circuit voltages of the battery clusters are larger than the charge protection threshold value and have obvious difference, judging that the charging maintenance is needed, otherwise, judging that the charging maintenance is not needed;
step B1.2: when a certain battery cluster is detected to reach a charging protection threshold, judging the state of charge of the system battery cluster and the open-circuit voltages of other battery clusters, if the state of charge of the battery cluster exceeds a preset range or the open-circuit voltage of the battery cluster is larger than the protection threshold, judging that charging maintenance is needed, otherwise, judging that the charging maintenance is not needed;
step B1.3: if the system needs to be charged and maintained, judging whether the energy storage system can be charged and maintained according to the external operating conditions of the system;
step B1.4: and if the system has the maintenance operation condition, starting a capacity utilization rate promotion control algorithm based on deep charging, simultaneously closing an inter-phase equalization algorithm and an intra-phase equalization algorithm, and then executing the step B2.
7. The method for improving the capacity utilization rate of the energy storage system of the high-voltage direct-hanging battery based on the deep charging of claim 6, wherein the step B2 comprises the following steps:
step B2.1: charging the system until a battery cluster voltage reaches a charging third-level alarm value, and reducing the charging power by half, wherein the charging third-level alarm value voltage is less than the charging second-level alarm value voltage and less than the charging first-level alarm value voltage;
step B2.2: after the power is halved, continuing to charge until the voltage of a battery cluster reaches a charging three-level alarm value, and halving the charging power again;
step B2.3: judging whether the charging power is lower than a charging power reduction threshold value, if so, keeping the charging power threshold value to be charged until a battery cluster voltage reaches a charging secondary alarm value, marking the battery cluster as deeply charged for maintenance, correcting the charge state of the battery cluster by a battery management system BMS (battery management system) and recording an x-phase y-th module of the battery cluster, wherein the symbol is M xy ；
Step B2.4: the system stops charging and the control system operates in a pure reactive working condition.
8. The method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep charging according to claim 7, wherein the step B3 comprises the following steps:
Step B3.1: selecting a z-th module which belongs to a battery cluster which is not subjected to deep charge maintenance in x phases and is marked as M xz ；
Step B3.2: in module M xy Superimposing an amplitude value on the modulation wave according with the preset condition and x-phase powerVoltage V in phase opposition xy Module M xy Discharging the middle battery cluster;
step B3.3: in module M xz Superimposing an amplitude and a voltage V on the modulated wave xy Voltage V of the same phase as the x-phase current xz ＝V xy Module M xz Charging the middle battery cluster;
step B3.4: module M xz Charging until the voltage of the battery cluster reaches a charging secondary alarm value, and module M xy Stopping charging, module M xz Stopping charging and marking as deep charging maintenance, and making y = z, and a module M xz Reset to M xy ；
Step B3.5: judging whether all the x-phase battery clusters complete deep charge maintenance or not, and returning to the module M3.1 for continuous operation if the x-phase battery clusters do not complete deep charge maintenance; if the x phase is maintained, the module M3.6 is operated;
step B3.6: judging whether deep charging maintenance is completed on all the three-phase battery clusters, and if not, operating a module M3.7; if the three phases are completely maintained, the deep charging maintenance of the whole system is completed;
step B3.7: injecting zero sequence voltage to make the non-maintained phase x charge until a battery cluster voltage reaches a charging secondary alarm value, recording the x-phase y-th module of the battery cluster, and the notation is M xy And returning to the module M3.1 to continue running.
9. A method for improving the capacity utilization rate of a high-voltage direct-hanging battery energy storage system based on full charge and full discharge is characterized in that the method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep discharge in claim 1 and the method for improving the capacity utilization rate of the high-voltage direct-hanging battery energy storage system based on deep charge in claim 5 comprise the following steps:
if the high-voltage direct-hung battery energy storage system based on deep discharge is started to carry out capacity utilization rate improvement control according to the system operation state and a maintenance instruction, the system operates according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep discharge, after the discharge maintenance is finished, the system recovers normal charge operation until the charge maintenance condition is met, the high-voltage direct-hung battery energy storage system based on deep discharge operates according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep discharge, and after the charge maintenance is finished, the system finishes one-time full charge and full discharge maintenance;
if the high-voltage direct-hung battery energy storage system based on deep charging is started to carry out capacity utilization rate improvement control according to the system operation state and the maintenance instruction, the system operates according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep charging, after charging maintenance is finished, the system recovers normal discharging operation until the discharging maintenance condition is met, the system operates according to the capacity utilization rate improvement method of the high-voltage direct-hung battery energy storage system based on deep discharging, and after discharging maintenance is finished, the system finishes one-time full-charging full-discharging maintenance.
CN202211027190.7A 2022-08-25 2022-08-25 Capacity utilization rate raising method for high-voltage direct-hanging battery energy storage system Active CN115395605B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211027190.7A CN115395605B (en) 2022-08-25 2022-08-25 Capacity utilization rate raising method for high-voltage direct-hanging battery energy storage system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211027190.7A CN115395605B (en) 2022-08-25 2022-08-25 Capacity utilization rate raising method for high-voltage direct-hanging battery energy storage system

Publications (2)

Publication Number Publication Date
CN115395605A true CN115395605A (en) 2022-11-25
CN115395605B CN115395605B (en) 2023-07-07

Family

ID=84122530

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211027190.7A Active CN115395605B (en) 2022-08-25 2022-08-25 Capacity utilization rate raising method for high-voltage direct-hanging battery energy storage system

Country Status (1)

Country Link
CN (1) CN115395605B (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104617621A (en) * 2015-01-28 2015-05-13 杭州高特电子设备有限公司 Improved battery pack maintaining method
CN108701876A (en) * 2016-02-17 2018-10-23 丰田自动车欧洲公司 System and method for battery discharge control
CN111555328A (en) * 2020-06-05 2020-08-18 南京工程学院 Intelligent state judgment and mode switching method for high-voltage direct-hanging energy storage system
US10992149B1 (en) * 2020-10-08 2021-04-27 Element Energy, Inc. Safe battery energy management systems, battery management system nodes, and methods
CN114336700A (en) * 2021-12-01 2022-04-12 国网江苏省电力有限公司盐城供电分公司 Method for controlling capacity utilization rate of medium-voltage direct-hanging energy storage system
CN114447970A (en) * 2022-01-21 2022-05-06 上海交通大学 High-voltage direct-hanging battery energy storage system and control method thereof
CN114884078A (en) * 2022-01-28 2022-08-09 上海交通大学 High-voltage direct-hanging system integrating reactive compensation and energy storage

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104617621A (en) * 2015-01-28 2015-05-13 杭州高特电子设备有限公司 Improved battery pack maintaining method
US20180183245A1 (en) * 2015-01-28 2018-06-28 Hangzhou Gold Electronic Equipment Inc., Ltd. Improved maintenance method of power battery pack
CN108701876A (en) * 2016-02-17 2018-10-23 丰田自动车欧洲公司 System and method for battery discharge control
CN111555328A (en) * 2020-06-05 2020-08-18 南京工程学院 Intelligent state judgment and mode switching method for high-voltage direct-hanging energy storage system
US10992149B1 (en) * 2020-10-08 2021-04-27 Element Energy, Inc. Safe battery energy management systems, battery management system nodes, and methods
CN114336700A (en) * 2021-12-01 2022-04-12 国网江苏省电力有限公司盐城供电分公司 Method for controlling capacity utilization rate of medium-voltage direct-hanging energy storage system
CN114447970A (en) * 2022-01-21 2022-05-06 上海交通大学 High-voltage direct-hanging battery energy storage system and control method thereof
CN114884078A (en) * 2022-01-28 2022-08-09 上海交通大学 High-voltage direct-hanging system integrating reactive compensation and energy storage

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
CHANG LIU等: "Self-Adaptation Control of Second-Life Battery Energy Storage System Based on Cascaded H-Bridge Converter", 《 IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS》 *
陈强: "高压直挂大容量电池储能功率转换***", 《中国优秀博硕士学位论文全文数据库(博士) 工程科技Ⅱ辑》 *
韩啸;陈强;李睿;: "储能型MMC电池荷电状态均衡策略", 电力电子技术, no. 04 *

Also Published As

Publication number Publication date
CN115395605B (en) 2023-07-07

Similar Documents

Publication Publication Date Title
Piao et al. Lithium‐ion battery cell‐balancing algorithm for battery management system based on real‐time outlier detection
CN111431231B (en) Battery grouping architecture based on flexible connection and redundancy
Kim et al. A series-connected self-reconfigurable multicell battery capable of safe and effective charging/discharging and balancing operations
CN104247201A (en) Power storage system and cartridge
Chen et al. A modular and reconfigurable battery system
CN109728369B (en) Self-adaptive control method and system of chain type energy storage system based on power battery
CN209982089U (en) Energy storage system primary topological structure based on PCS and DC-DC converter stack
Ahmad et al. State-of-charge balancing control for On/OFF-line internal cells using hybrid modular multi-level converter and parallel modular dual L-bridge in a grid-scale battery energy storage system
CN102842937B (en) Charging/discharging controlling system of serial storage battery set and charging/discharging optimizing method
CN112564149A (en) Medium-voltage direct-hanging energy storage system and online redundancy control method thereof
Babu et al. Comparative analysis of passive and active cell balancing of li ion batteries
Chen et al. Sneak circuit theory based approach to avoiding short-circuit paths in reconfigurable battery systems
Ahmad et al. State-of-charge balancing control for optimal cell utilisation of a grid-scale three-phase battery energy storage system using hybrid modular multilevel converter topology without redundant cells
CN112134319B (en) Energy feedback type echelon battery charge-discharge equalization system and control method thereof
CN116388345B (en) Battery PACK circuit system and control method
Daneshvardehnavi et al. A case study for connecting bidirectional PEV station for reactive power support to the GLEAMM prototype microgrid
Wang et al. Reconfigurable battery energy storage system for utility-scale applications
CN116488304A (en) Energy storage converter of energy storage system and electricity supplementing method
CN115395605B (en) Capacity utilization rate raising method for high-voltage direct-hanging battery energy storage system
Wang et al. State of charge balancing control of a multi-functional battery energy storage system based on a 11-level cascaded multilevel PWM converter
Kamel et al. Smart SOP architectures and power control managements between light DC railway and LV distribution network
Mathe et al. State of charge balancing after hot swap for cascaded H-bridge multilevel converters
Kim et al. Self-reconfigurable multicell batteries
Chen et al. A unified control scheme of battery energy storage system based on cascaded H-bridge converter
Liang et al. A comparison of the battery fault tolerance of modular multilevel converters with half-bridge and full-bridge submodules

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant