Power storage resource management device and control method thereof

Abstract

The present invention discloses a management device for a power storage source and a control method thereof. In the management device according to the present invention, a control unit is configured to acquire operating characteristic information of the power storage source from a sensor unit to determine an operating power limit of the power storage source, determine a charging power or discharging power of the power storage source using the operating characteristic information while the power storage source is operating, and suspend the operation of the power storage source when a first operation suspension condition is satisfied in which the charging power or the discharging power is greater than a preset unstable power range of the power conversion system (PCS) and is greater than the operating power limit by a first threshold value, and suspend the operation of the power storage source when a second operation suspension condition is satisfied in which the charging power or the discharging power is within a preset unstable power range of the PCS and is greater than the operating power limit by a second threshold value (greater than the first threshold value).

Description

[Technical field]

[0001] The present invention relates to a power storage source management device and a control method thereof, and more particularly to a power storage source management device and a control method thereof that can prevent a phenomenon in which charging or discharging of a power storage source is interrupted in the latter half of the charging or discharging process of the power storage source.

[0002] This application claims priority to Korean Patent Application No. 10-2021-0149215, filed on November 2, 2021, and all contents disclosed in the specification and drawings of that application are incorporated herein by reference. [Background technology]

[0003] Recently, interest in energy has been exploding around the world due to resource depletion and serious climate change. As a result, smart grid and renewable energy technologies have been in the spotlight. Renewable energy has the disadvantage of not having a constant energy supply, so technologies to compensate for this are needed.

[0004] Energy Storage Systems (ESS) are used to make up for the shortcomings of renewable energy and to build smart grids more efficiently.

[0005] An ESS is a system that stores electricity produced through renewable energy sources or unused or excess electricity from the power grid in a power storage source, and supplies the stored electricity to the power system when it is needed, thereby increasing the efficiency of electricity usage.

[0006] The ESS includes a power storage source including multiple batteries, a power conversion system (PCS), an energy management system (EMS), and the like.

[0007] The PCS converts the current characteristics to output the power stored in the power storage source to the system, and performs functions such as monitoring and control, independent operation, and system linked protection. The EMS manages the ESS as a whole, and in particular plays a role in adjusting the charging and discharging conditions of the power storage source to operate the ESS more efficiently.

[0008] The PCS charges the power storage source using electricity supplied from the power grid or renewable energy power plants in accordance with the operation policy set by the EMS, and also discharges the power storage source to provide power to the power system in accordance with the operation policy set by the EMS.

[0009] The PCS has a controllable power specification. For example, if the power specification of the PCS is 5000 kW, the PCS can supply a maximum of 5000 kW of charging power to the power storage source, or can receive a maximum of 5000 kW of discharging power from the power storage source.

[0010] The PCS monitors the voltage and current of the power transmission line to ensure that the charging power and discharging power of the power storage source do not exceed the controllable power specifications. The voltage measurement sensor and current measurement sensor included in the PCS have a measurement error. If the voltage measurement sensor and current measurement sensor have an error within 1%, the accuracy of the power control of the PCS may decrease when the charging power and discharging power are low. In the above example, the power corresponding to an error of 1% is 50 kW. Therefore, when the charging power and discharging power are below 50 kW, the accuracy of the power control of the PCS may decrease. Hereinafter, the power specification range where the accuracy of the power control of the PCS decreases is defined as the unstable power range.

[0011] The power storage source has a management device. The management device determines an allowable operating power limit of the power storage source based on the state of charge and temperature of the power storage source. The operating power limit is the maximum value of charging power or discharging power that the power storage source can tolerate. If the charging power input to the power storage source or the discharging power output from the power storage source exceeds the operating power limit by a predetermined percentage, the management device of the power storage source interrupts charging and discharging of the power storage source in consideration of safety. For example, if the condition for interrupting charging and discharging is set to exceed the operating power limit by 10 to 20%, the management device immediately interrupts charging and discharging of the power storage source when the charging power or discharging power of the power storage source exceeds the operating power limit by 10 to 20%.

[0012] The power range in which the accuracy of the power control of the PCS decreases is when the charge state of the power storage source approaches full charge or full discharge. The closer to full charge or full discharge, the lower the charging power or discharging power becomes, and eventually it falls below the unstable power range of the PCS.

[0013] As described above, in the unstable power range, the accuracy of the power control of the PCS decreases. That is, it becomes difficult to accurately control the charging power and discharging power to the level required by the power storage source management device. Therefore, in the unstable power range, events corresponding to the charge / discharge interruption condition frequently occur. That is, there are frequent cases where the charging power supplied to the power storage source or the discharging power output from the power storage source exceeds the operating power limit by a certain percentage. For this reason, a phenomenon occurs in which the power storage source cannot be fully charged or fully discharged, causing the operation to suddenly stop. Summary of the Invention [Problem to be solved by the invention]

[0014] The present invention has been devised in light of the background of the conventional technology as described above, and has an object to provide a power storage source management device and a control method thereof, which have improved control logic to improve the phenomenon in which the operation of the power storage source suddenly stops even if the charging power or discharging power of the power storage source falls below the unstable power range of the PSC. [Means for solving the problem]

[0015] In order to achieve the above technical objective, a power storage source management device according to one aspect of the present invention includes a sensor unit that measures operating characteristics of the power storage source, and a control unit operably coupled to the sensor unit.

[0016] Preferably, the control unit may be configured to (i) acquire operating characteristic information of the power storage source from the sensor unit and determine an operating power limit of the power storage source, (ii) determine a charging power supplied from a power conversion system (PCS) or a discharging power provided to a PCS side using the operating characteristic information while the power storage source is operating, (iii) suspend operation of the power storage source when a first operation suspension condition is satisfied in which the charging power or the discharging power is greater than a preset unstable power range of the PCS and the charging power or the discharging power is greater than a first threshold value or greater than the operating power limit, and (iv) suspend operation of the power storage source when a second operation suspension condition is satisfied in which the charging power or the discharging power is within a preset unstable power range of the PCS and the charging power or the discharging power is greater than a second threshold value (greater than the first threshold value) greater than the operating power limit.

[0017] According to one aspect, the control unit may be configured to receive operating characteristic information including a charge / discharge current, a voltage, and a temperature of the power storage source from the sensor unit, accumulate the charge / discharge current to determine a state of charge of the power storage source, and determine an operating power limit of the power storage source corresponding to the determined state of charge and the received temperature by referring to lookup information defining a correlation between the state of charge, temperature, and an operating power limit.

[0018] According to another aspect, the control unit may be provided with information from the PCS regarding a preset unstable power range of the PCS.

[0019] Preferably, the first threshold value may be between 10% and 30% of the operating power limit, and the second threshold value may be between 30% and 60% of the operating power limit.

[0020] Optionally, the second threshold value may be increased as the charging power or discharging power of the power storage source becomes lower.

[0021] According to yet another embodiment, the power storage source may include first to nth battery racks.

[0022] To achieve the above technical objective, a power storage source management device according to another aspect of the present invention may include first to nth slave control units provided in the first to nth battery racks, respectively, and a master control unit connected to the first to nth slave control units so as to be able to communicate with the first to nth slave control units.

[0023] Each of the first to nth slave control units may be configured to acquire operating characteristic information of the battery rack to which it is attached from a sensor unit, determine an operating power limit and charging power or discharging power of the battery rack using the operating characteristic information, and provide the determined operating power limit and charging power or discharging power to the master control unit.

[0024] Preferably, the master control unit may be configured to determine a total operating power limit and a total charging power or a total discharging power by adding up the operating power limit and the charging power or the discharging power transmitted from the first to nth slave control units, and provide an operation interruption message to the first to nth slave control units when a first operation interruption condition is satisfied in which the total charging power or the total discharging power is greater than a preset unstable power range of a PCS and the total charging power or the total discharging power is greater than the total operating power limit by a first threshold value, and to provide an operation interruption message to the first to nth slave control units when a second operation interruption condition is satisfied in which the total charging power or the total discharging power is within a preset unstable power range of a PCS and the total charging power or the total discharging power is greater than the total operating power limit by a second threshold value (greater than the first threshold value).

[0025] A control method for a power storage source management device according to yet another aspect of the present invention for achieving the above technical objective may include the steps of: acquiring operating characteristic information of the power storage source from a sensor unit that measures operating characteristics of the power storage source; determining an operating power limit of the power storage source using the operating characteristic information; determining a charging power supplied from a power conversion system (PCS) or a discharging power provided to a PCS side using the operating characteristic information while the power storage source is operating; interrupting the operation of the power storage source when a first operation interruption condition is satisfied in which the charging power or the discharging power is greater than a preset unstable power range of the PCS and the charging power or the discharging power is greater than a first threshold value or greater than the operating power limit; and interrupting the operation of the power storage source when a second operation interruption condition is satisfied in which the charging power or the discharging power is within a preset unstable power range of the PCS and the charging power or the discharging power is greater than a second threshold value (greater than the first threshold value) greater than the operating power limit.

[0026] In order to achieve the above technical objective, a control method for a power storage source management device according to yet another aspect of the present invention is a control method for a power storage source management device including first to nth slave control units respectively provided in first to nth battery racks, and a master control unit connected to the first to nth slave control units so as to be communicable with the first to nth slave control units, the control method including a step in which each of the first to nth slave control units acquires operating characteristic information from a sensor unit that measures operating characteristics of the battery rack provided therein, determines an operating power limit and a charging power or discharging power of the battery rack, and provides the operating power limit and the charging power or discharging power to the master control unit; a step in which the master control unit sums up the operating power limit and the charging power or discharging power transmitted from the first to nth slave control units to determine an overall operating power limit and an overall charging power or overall discharging power; The method may include a step of providing an operation interruption message to the first to nth slave control units when a first operation interruption condition is satisfied, where the total discharge power is greater than a preset unstable power range of the PCS and the total charging power or the total discharging power is greater than the total operating power limit by a first threshold value; a step of the master control unit providing an operation interruption message to the first to nth slave control units when a second operation interruption condition is satisfied, where the total charging power or the total discharging power is within a preset unstable power range of the PCS and the total charging power or the total discharging power is greater than the total operating power limit by a second threshold value (greater than the first threshold value); and a step of the first to nth slave control units interrupting operation of the battery rack to which they are attached in response to receiving the operation interruption message. Effect of the Invention

[0027] According to the present invention, the condition for interrupting charging / discharging is relaxed when the charging power or discharging power of the power storage source falls below the unstable power range of the PCS. Therefore, the power storage source can be charged to a fully charged state and discharged to a fully discharged state while preventing the phenomenon that the operation of the power storage source is interrupted in the latter half of charging or discharging. This allows the capacity of the power storage source to be utilized to the maximum.

[0028] The drawings attached to this specification are intended to illustrate preferred embodiments of the present invention and serve to facilitate a further understanding of the technical ideas of the present invention as well as the content of the invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in the drawings. [Brief description of the drawings]

[0029] [Figure 1] 1 is a schematic configuration diagram of a power storage source management device according to a first embodiment of the present invention. [Diagram 2] FIG. 11 is a schematic configuration diagram of a power storage source management device according to a second embodiment of the present invention. [Diagram 3] FIG. 2 is a flow diagram of a control method for a power storage resource management device according to a first embodiment of the present invention. [Figure 4] FIG. 6 is a flow chart showing a control method for a power storage resource management device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms and words used in this specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, but are to be construed as being in accordance with the meaning and concept of the technical idea of ​​the present invention, in accordance with the principle that the inventor himself can appropriately define the concept of the term in order to best describe the invention. Therefore, it should be understood that the embodiment described in this specification and the configuration shown in the drawings are merely the most preferred embodiment of the present invention, and do not represent the entire technical idea of ​​the present invention, and therefore there may be various equivalents and modifications that can be substituted therefor at the time of this application.

[0031] FIG. 1 is a schematic diagram of a power storage resource management device 10 according to a first embodiment of the present invention.

[0032] 1, a power storage source management device 10 according to a first embodiment is coupled to a power storage source 11. The power storage source 11 is connected to a PCS 13 via a switch 12. The PCS 13 is included in an ESS, and converts current characteristics and performs monitoring and control, independent operation, and system-linked protection functions in order to output power stored in the power storage source 11 to a system and to supply power from the system to the power storage source 11.

[0033] The power storage source 11 includes a plurality of battery cells 14. The plurality of battery cells 14 may be connected in series and / or in parallel. In one example, the plurality of batteries may be mounted on a battery rack. The battery rack is widely used in ESSs and includes a rack structure on which the plurality of battery cells 14 can be loaded. Preferably, the battery rack may be a component included in the ESS.

[0034] The plurality of battery cells 14 may be lithium ion batteries, although the present invention is not limited by the type of battery cells 14 .

[0035] The switch 12 is a component that connects or disconnects the PCS 13 and the power storage source 11. The switch 12 may be a relay switch or a power semiconductor switch. However, the present invention is not limited by the type of the switch 12.

[0036] The power storage source management device 10 includes a sensor unit 15 that measures the operating characteristics of the power storage source 11. Preferably, the sensor unit 15 includes a voltage measurement unit 15a, a current measurement unit 15b, and a temperature measurement unit 15c.

[0037] The voltage measurement unit 15a measures the voltage of each battery cell at regular time intervals while the multiple battery cells 14 are being charged or discharged, and outputs the measured voltage values ​​to the control unit 16.

[0038] The voltage measurement unit 15a may be a voltage measurement circuit known in the art. Since voltage measurement circuits are well known, detailed description thereof will be omitted.

[0039] The current measuring unit 15b measures the charge / discharge current flowing through the multiple battery cells 14 at regular time intervals, and outputs the current measurement value to the control unit 16.

[0040] The current measuring unit 15b may be a current measuring circuit known in the art. The current measuring unit 15b may be a Hall sensor or a sense resistor that outputs a voltage value corresponding to the magnitude of the current. The voltage value can be converted into a current value according to Ohm's law.

[0041] The temperature measurement unit 15c measures the temperature of each battery cell 14 at regular time intervals while the battery cells 14 are being charged or discharged, and outputs the measured temperature value to the control unit 16.

[0042] The temperature measuring unit 15c may be a temperature measuring circuit known in the art. The temperature measuring unit 15c may be a thermocouple or a temperature measuring element that outputs a voltage value corresponding to the temperature. The voltage value can be converted to a temperature value using a voltage-temperature conversion lookup table (function).

[0043] The power storage source management device 10 includes a control unit 16. The control unit 16 acquires operating characteristic information of the power storage source 11 from the sensor unit 15 and determines an operating power limit of the power storage source 11. The operating characteristic information relates to the voltage, charge / discharge current, and temperature of the multiple battery cells 14 included in the power storage source 11. The operating power limit is the maximum value of charging power that can be applied to the power storage source 11 or the maximum value of discharging power that can be output from the power storage source 11 to the system.

[0044] The control unit 16 may accumulate the charge / discharge currents for each of the multiple battery cells 14 to determine the state of charge of each battery cell, and may sum up the states of charge of the battery cells to determine the state of charge (SOC) of the power storage source 11.

[0045] The charge / discharge current is accumulated using a coulomb counting method known in the technical field to which the present invention pertains. When accumulating the charge / discharge current, the initial value of the state of charge may be determined using a stabilized voltage measured after the plurality of battery cells 14 maintains a no-load state for a predetermined time. That is, the state of charge corresponding to the stabilized voltage may be looked up by referring to lookup information that predefines a correlation between the stabilized voltage and the state of charge, and the looked-up state of charge may be set as the initial value of the state of charge.

[0046] In another example, the control unit 16 may input information regarding the voltage, charge / discharge current, and temperature of each of the multiple battery cells 14 to an extended Kalman filter to determine the state of charge of each battery cell, and may sum up the states of charge of the battery cells to determine the state of charge of the power storage source 11. Extended Kalman filters capable of determining the state of charge from the voltage, charge / discharge current, and temperature of a battery cell are already known in the art.

[0047] For an example of estimation of the state of charge using an extended Kalman filter, refer to the paper by Gregory L. Plett, “Extended Kalman filtering for battery management systems of LiPB-based HEV battery packs Parts 1, 2 and 3” (Journal of Power Source 134, 2004, 252-261), and the above paper may be incorporated as part of this specification.

[0048] Preferably, the control unit 16 can determine an operating power limit corresponding to the current state of charge and the current temperature of the power storage source 11 by referring to lookup information that defines a correlation between the state of charge and temperature of the power storage source 11 and the operating power limit.

[0049] The power storage source 11 is kept at a uniform temperature by a heating, ventilation, and air conditioning (HVAC) device. Thus, the temperature of the power storage source 11 may be the average temperature of the battery cells. Or, alternatively, the temperature of the power storage source 11 may be the maximum temperature of the battery cells.

[0050] The operating power limit can be determined by other known methods in addition to referencing lookup information, and the present invention is not limited in any way to a specific method for determining the operating power limit.

[0051] In addition, the control unit 16 can determine the charging power supplied from the PCS 13 to the power storage source 11 while the power storage source 11 is being charged or discharged, or the discharging power provided from the power storage source 11 to the PCS 13 side.

[0052] To this end, the control unit 16 may determine the charging power or discharging power by multiplying the total voltage of the battery cells 14 by the charging / discharging current. The total voltage may be determined by adding up the voltages of the individual battery cells. The voltage and the charging / discharging current of each battery cell are obtained by referring to the operating characteristic information obtained via the sensor unit 15.

[0053] The control unit 16 may directly measure the current and voltage of a power line connecting the PCS 13 and the power storage source 11 to determine the charging power supplied from the PCS 13 to the power storage source 11 or the discharging power provided from the power storage source 11 to the PCS 13. In this case, the power storage source management device 10 may separately include a current measuring unit (not shown) and a voltage measuring unit (not shown) for monitoring the current and voltage of the power line.

[0054] The control unit 16 can maintain or interrupt the operation of the power storage source 11 by determining whether the charging power or discharging power of the power storage source 11 falls within a preset unstable power range of the PCS 13 and whether the charging power or discharging power is greater than the operating power limit by a threshold value or more.

[0055] According to one embodiment, the control unit 16 may determine whether a condition (a first operation interruption condition) is met in which the charging power or discharging power of the power storage source 11 is greater than a preset unstable power range of the PCS 13 and the charging power or discharging power is greater than or equal to a first threshold value greater than the operating power limit of the power storage source 11. If the first operation interruption condition is met, the control unit 16 may turn off the switch 12 to interrupt the charging or discharging of the power storage source 11. Conversely, if the first operation interruption condition is not met, the control unit 16 may maintain the switch 12 turned on to maintain the charging or discharging of the power storage source 11.

[0056] According to another aspect, the control unit 16 may determine whether a condition (a second operation interruption condition) is met in which the charging power or discharging power of the power storage source 11 is within a preset unstable power range of the PCS 13 and the charging power or discharging power is equal to or greater than a second threshold (greater than the first threshold) than the operating power limit of the power storage source 11. If the second operation interruption condition is met, the control unit 16 may turn off the switch 12 to interrupt the charging or discharging of the power storage source 11. Conversely, if the second operation interruption condition is not met, the control unit 16 may maintain the switch 12 turned on to maintain the charging or discharging of the power storage source 11.

[0057] The first threshold value may be set to 10% to 30% based on the operating power limit. In this case, the control unit 16 may interrupt the operation of the power storage source 11 when the condition that the charging power or discharging power of the power storage source 11 is greater than the unstable power range preset in the PCS 13 and the charging power or discharging power is 10% to 30% or more higher than the operating power limit of the power storage source 11 is satisfied.

[0058] The second threshold value may be set to 30% to 60% based on the operating power limit. In this case, the control unit 16 may interrupt the operation of the power storage source 11 when the conditions that the charging power or discharging power of the power storage source 11 is within a preset unstable power range of the PCS 13 and the charging power or discharging power is 30% to 60% or more higher than the operating power limit of the power storage source 11 are satisfied.

[0059] According to the present invention, the second operation interruption condition is applied when the charging power or discharging power of the power storage source 11 is within the unstable power range preset by the PCS 13. The unstable power range is caused by the measurement error of the voltage and current of the PCS. In one example, if the measurement error of the voltage and current is 1%, the unstable power range is a power range equivalent to the output specification of the PCS multiplied by the measurement error. If the output specification of the PCS is 5000 kW, the unstable power range is a range of 0 to 50 kW.

[0060] The charging power or discharging power of the power storage source 11 enters the unstable power range when the power storage source 11 approaches a fully charged state or a fully discharged state. At this time, the charging power or discharging power becomes very low, so there is no safety issue even if the second threshold value is increased from the first threshold value. Since the power storage source 11 includes multiple battery cells 14, even if the second threshold value is greater than the first threshold value, from the viewpoint of each battery cell, the degree to which the operating power limit is exceeded is not at a level of concern.

[0061] As described above, if the charge / discharge interruption condition of the power storage source 11 is increased from the first threshold value to the second threshold value when the charge power or discharge power of the PCS 13 enters the unstable power range, the problem of the operation of the power storage source 11 being suddenly interrupted in the latter half of the charge or discharge can be solved without causing a safety problem for the battery cells, and the power storage source 11 can be utilized from a fully charged state to a fully discharged state, thereby improving the energy usage efficiency.

[0062] Meanwhile, the second threshold value may be adaptively changed according to the level of the charging power or discharging power of the power storage source 11. In one example, the smaller the charging power or discharging power of the power storage source 11 is within the unstable power range preset by the PCS 13, the more the second threshold value may be gradually increased. This is because the lower the charging power or discharging power is, the less likely it is that a safety issue will occur in the battery cells.

[0063] The power storage resource management device 10 may further include a storage medium 17 and a communication interface 18.

[0064] There is no particular limitation on the type of storage medium 17, so long as it is capable of recording and erasing data and / or information. As an example, storage medium 17 may be a random access memory (RAM), a read-only memory (ROM), a register, a flash memory, a hard disk, or a magnetic recording medium.

[0065] The storage medium 17 can be electrically connected to the control unit 16 via, for example, a data bus so as to be accessible by the control unit 16 .

[0066] The storage medium 17 stores and / or updates and / or erases and / or transmits programs including various control logics executed by the control unit 16, and / or data generated when the control logics are activated, and / or preset data, parameters, lookup information / tables, etc.

[0067] The control unit 16 transmits and receives information and / or data to and from the PCS 13 via the communication interface 18. Preferably, the control unit 16 may receive information regarding the unstable power range of the PCS 13 via the communication interface 18 and record the information in the storage medium 17. The information regarding the unstable power range stored in the storage medium 17 may be referred to when determining whether the first operation interruption condition and the second operation interruption condition are satisfied.

[0068] Furthermore, the control unit 16 may transmit the operating power limit to the PCS 13 side via the communication interface 18. Then, the PCS 13 supplies charging power to the power storage source 11 so as not to exceed the operating power limit. At this time, the PCS 13 converts AC power of the power grid into DC power corresponding to the charging power and provides it to the power storage source 11. Furthermore, the PCS 13 may receive discharge power in the form of DC from the power storage source 11 within a range not exceeding the operating power limit, convert the DC into AC, and supply it to the power grid.

[0069] The communication interface 18 may be a known wired or wireless communication interface supporting short-range or long-range communication. By way of example, the communication interface 18 may be a controller area network (CAN) communication interface, a daisy-chain interface, an Ethernet communication interface, or a short-range wireless communication interface such as WI-FI, Bluetooth, or ZigBee, but the present invention is not limited thereto.

[0070] FIG. 2 is a schematic diagram of a power storage resource management device 20 according to a second embodiment of the present invention.

[0071] 2, in the second embodiment, the power storage source 11 includes first to n-th battery racks 11-1 to 11-n. Each battery rack includes a plurality of battery cells connected in series and / or parallel, similar to the power storage source 11 in the first embodiment.

[0072] The power storage source management device 20 includes first to n-th slave control units 16-1 to 16-n coupled to the first to n-th battery racks 11-1 to 11-n, respectively. The first to n-th slave control units 16-1 to 16-n include first to n-th sensor units 15-1 to 15-n coupled to the first to n-th battery racks 11-1 to 11-n, respectively. Each of the first to n-th sensor units 15-1 to 15-n includes a voltage measurement unit 15a, a current measurement unit 15b, and a temperature measurement unit 15c, similar to the first embodiment.

[0073] Moreover, the power storage source management device 20 includes first to n-th storage media 17-1 to 17-n coupled to the first to n-th slave control units 16-1 to 16-n, respectively. Furthermore, the power storage source management device 20 includes first to n-th communication interfaces 18-1 to 18-n coupled to the first to n-th slave control units 16-1 to 16-n, respectively. The configurations relating to the first to n-th storage media 17-1 to 17-n and the first to n-th communication interfaces 18-1 to 18-n are substantially similar to those in the first embodiment.

[0074] Furthermore, the power storage resource management device 20 includes a master control unit 21. The master control unit 21 can be operatively coupled to a storage medium 22 and a communication interface 23. The configurations of the storage medium 22 and the communication interface 23 are substantially similar to the storage medium 17 and the communication interface 18 of the first embodiment.

[0075] The master control unit 21 can transmit and receive data and / or information to and from the first to n-th slave control units 16-1 to 16-n via the communication interface .

[0076] In the following description, it is clear that when the master control unit 21 and the first to n-th slave control units 16-1 to 16-n transmit and receive data and / or information, the communication interfaces 18-1 to 18-n, 23 should be used. Therefore, when describing the transmission and reception of data and / or information between the control units, reference to the communication interfaces will be omitted.

[0077] Preferably, the first to n-th slave control units 16-1 to 16-n perform substantially the same operations.

[0078] Specifically, the first slave control unit 16-1 acquires operating characteristic information from a sensor unit 15-1 that measures the operating characteristics of the first battery rack 11-1 in which the first slave control unit 16-1 is installed, determines an operating power limit for the first battery rack 11-1, and transmits the operating power limit to the master control unit 21 through communication. The second slave control unit 16-2 to the n-th slave control unit 16-n also determine operating power limits for the second to n-th battery racks 11-2 to 11-n in which they are installed, respectively, and transmit the operating power limits to the master control unit 21 through communication. The method of determining the operating power limits is substantially similar to that in the first embodiment.

[0079] In addition, the first slave control unit 16-1 determines the charging power or discharging power while the first battery rack 11-1 is being charged or discharged, and provides the charging power or discharging power to the master control unit 21 through communication. The second slave control unit 16-2 to the n-th slave control unit 16-n also determine the charging power or discharging power of the second to n-th battery racks 11-2 to 11-n to which they are attached, and transmit them to the master control unit 21 through communication. The method of determining the charging power or discharging power is substantially similar to that of the first embodiment.

[0080] When the operating power limits are transmitted from the first to n-th slave control units 16-1 to 16-n, the master control unit 21 can determine the overall operating power limit of the first to n-th battery racks 11-1 to 11-n by adding up all the respective values.

[0081] Furthermore, when charging power or discharging power is transmitted from the first to nth slave control units 16-1 to 16-n, the master control unit 21 can add up all the values ​​to determine the total charging power or total discharging power of the first to nth battery racks 11-1 to 11-n.

[0082] Furthermore, according to one aspect, the master control unit 21 judges whether or not a condition (first operation interruption condition) is satisfied in which the total charging power or the total discharging power is greater than the unstable power range preset in the PCS 13 and the total charging power or the total discharging power is greater than the total operating power limit by a first threshold value. Preferably, the first threshold value can be set to 10% to 30% of the total operating power limit as in the first embodiment, but the present invention is not limited thereto.

[0083] If the first operation interruption condition is satisfied, the master control unit 21 transmits an operation interruption message to the first to n-th slave control units 16-1 to 16-n through communication. On the other hand, if the first operation interruption condition is not satisfied, the master control unit 21 transmits an operation maintenance message to the first to n-th slave control units 16-1 to 16-n through communication.

[0084] According to another aspect, the master control unit 21 judges whether or not a condition (second operation interruption condition) is satisfied in which the total charging power or the total discharging power is within a preset unstable power range of the PCS 13 and is equal to or greater than a second threshold (greater than the first threshold) than the total operating power limit. Preferably, the second threshold can be set to 30% to 60% of the total operating power limit, as in the first embodiment, but the present invention is not limited thereto.

[0085] If the second operation interruption condition is satisfied, the master control unit 21 transmits an operation interruption message to the first through n-th slave control units 16-1 through 16-n through communication. On the other hand, if the second operation interruption condition is not satisfied, the master control unit 21 transmits an operation maintenance message to the first through n-th slave control units 16-1 through 16-n through communication.

[0086] When the first slave control unit 16-1 receives an operation interruption message from the master control unit 21 through communication, it turns off the switch 12-1 disposed in the first battery rack 11-1 in which it is installed, thereby interrupting the charging or discharging of the first battery rack 11-1. On the other hand, when the first slave control unit 16-1 receives an operation maintenance message from the master control unit 21 through communication, it maintains the turned-on state of the switch 12-1 disposed in the first battery rack 11-1 in which it is installed, thereby continuing to maintain the charging or discharging of the first battery rack 11-1.

[0087] Like the first slave control unit 16-1, the second to nth slave control units 16-2 to 16-n also suspend the operation of the battery rack in which they are installed if they receive an operation interruption message through communication, and conversely, if they receive an operation maintenance message through communication, they continue to maintain the operation of the battery rack in which they are installed.

[0088] FIG. 3 is a flow chart illustrating a control method for the power storage resource management device according to the first embodiment of the present invention.

[0089] The method shown in Fig. 3 is a control method of the power storage source management device 10 according to the first embodiment, and unless otherwise specified, the main body that executes the steps in Fig. 3 is the control unit 16 of the first embodiment. Also, the steps in Fig. 3 can be periodically repeated at regular time intervals.

[0090] 1 and 3, the control unit 16 acquires operating characteristic information of the power storage source 11 from the sensor unit 15 in step S10.

[0091] Next, in step S20, the control unit 16 determines an operating power limit for the power storage source 11 using the operating characteristic information.

[0092] Next, in step S30, the control unit 16 determines the charging power supplied from the PCS 13 to the power storage source 11, or the discharging power supplied from the power storage source 11 to the PCS 13 side.

[0093] Next, in step S40, the control unit 16 determines whether the charging power or discharging power of the power storage source 11 is greater than the unstable power range set in advance in the PCS 13.

[0094] If the determination in step S40 is YES, in step S50, the control unit 16 determines whether the charging power or discharging power of the power storage source 11 is equal to or greater than a first threshold value above an operating power limit corresponding to the state of charge and temperature of the power storage source 11.

[0095] If the determination in step S50 is YES, then in step S70, the control unit 16 turns off the switch 12 provided in the power line to interrupt the operation of the power storage source 11. On the other hand, if the determination in step S50 is NO, then in step S80, the control unit 16 maintains the switch 12 provided in the power line in the turned-on state to maintain the operation of the power storage source 11.

[0096] On the other hand, if the judgment in step S40 is NO, the control unit 16 determines in step S60 whether the charging power or discharging power of the power storage source 11 is equal to or greater than a second threshold value (greater than the first threshold value) than the operating power limit corresponding to the state of charge and temperature of the power storage source 11.

[0097] If the determination in step S60 is YES, then in step S90, the control unit 16 turns off the switch 12 provided in the power line to interrupt the operation of the power storage source 11. On the other hand, if the determination in step S60 is NO, then in step S100, the control unit 16 maintains the switch 12 provided in the power line in the turned-on state to maintain the operation of the power storage source 11.

[0098] According to the present invention, when the charging power or discharging power of the power storage source 11 falls within the unstable power range preset in the PCS 13, the charge / discharge interruption condition of the power storage source 11 is increased and relaxed, thereby preventing the operation of the power storage source 11 from being interrupted in the latter half of charging or discharging. This allows the power storage source 11 to be charged to a fully charged state and discharged to a fully discharged state, making the most of the capacity of the power storage source 11.

[0099] FIG. 4 is a flow chart showing a control method of the power storage resource management device 20 according to the second embodiment of the present invention.

[0100] The method shown in Fig. 4 is a control method of the power storage source management device 20 according to the second embodiment, and the steps in Fig. 4 are executed mainly by the first to n-th slave control units 16-1 to 16-n of the second embodiment or the master control unit 21. Moreover, the steps in Fig. 4 can be periodically repeated at regular time intervals.

[0101] 2 and 4, in step S200, the first slave control unit 16-1 acquires operating characteristic information from the sensor unit 15-1 that measures the operating characteristics of the first battery rack 11-1 to which the first slave control unit 16-1 is attached, determines an operating output limit for the first battery rack 11-1, and provides it to the master control unit 21. The second to n-th slave control units 16-2 to 16-n also determine operating output limits for the second to n-th battery racks 11-2 to 11-n, similar to the first slave control unit 16-1, and provide it to the master control unit 21.

[0102] Next, in step S210, the master control unit 21 adds up all the operating output limits transmitted from the first to n-th slave control units 16-1 to 16-n to determine an overall operating output limit.

[0103] Next, in step S220, the master control unit 21 determines the total charging power supplied from the PCS 13 or the total discharging power supplied to the PCS 13 side while the first and second battery racks 11-1 to 11-n are operating.

[0104] In order to determine the total charging power or total discharging power, the first to n-th slave control units 16-1 to 16-n may determine the charging power or discharging power of the battery rack to which they are attached and transmit it to the master control unit 21 through communication. Then, the master control unit 21 may determine the total charging power or total discharging power by adding up all the charging powers or discharging powers of the battery racks. Alternatively, the master control unit 21 may measure the voltage and current of the power line using a voltage measuring unit (not shown) and a current measuring unit (not shown) disposed on the power line, respectively, and multiply the voltage and current to determine the total charging power or total discharging power. The method of determining the charging power or discharging power of each battery rack has been described above.

[0105] After step S220, step S230 is performed.

[0106] In step S230, the master control unit 21 determines whether the total charging power or the total discharging power is greater than the preset unstable power range of the PCS 13.

[0107] If the determination in step S230 is YES, the master control unit 21 determines in step S240 whether the total charging power or the total discharging power is equal to or greater than the total operating output limit by a first threshold value.

[0108] If the determination in step S240 is YES, the master control unit 21 transmits an operation interruption message to the first to n-th slave control units 16-1 to 16-n through communication in step S250. Then, in step S260, the first to n-th slave control units 16-1 to 16-n turn off the switches of the battery racks to which they are attached, interrupting the operation of the battery racks.

[0109] If the determination in step S240 is NO, the master control unit 21 transmits an operation maintenance message to the first to n-th slave control units 16-1 to 16-n through communication in step S270. Then, in step S280, the first to n-th slave control units 16-1 to 16-n maintain the switches of the battery racks to which they are attached in the turned-on state to maintain the operation of the battery racks.

[0110] On the other hand, if the determination in step S230 is NO, the master control unit 21 determines in step S255 whether the total charging power or the total discharging power is equal to or greater than the total operating output limit by a second threshold value (greater than the first threshold value).

[0111] If the determination in step S255 is YES, the master control unit 21 transmits an operation interruption message to the first to n-th slave control units 16-1 to 16-n through communication in step S290. Then, in step S300, the first to n-th slave control units 16-1 to 16-n turn off the switches of the battery racks to which they are attached, interrupting the operation of the battery racks.

[0112] If the determination in step S255 is NO, the master control unit 21 transmits an operation maintenance message to the first to n-th slave control units 16-1 to 16-n through communication in step S310. Then, in step S320, the first to n-th slave control units 16-1 to 16-n maintain the switches of the battery racks to which they are attached in the turned-on state to maintain the operation of the battery racks.

[0113] According to the present invention, when the total charging power or total discharging power of the first to nth battery racks 11-1 to 11-n falls within the unstable power range preset in the PCS 13, the charge / discharge interruption conditions of the first to nth battery racks 11-1 to 11-n are increased and relaxed, thereby preventing the operation of the first to nth battery racks 11-1 to 11-n from being interrupted in the latter half of charging or discharging. This allows the first to nth battery racks 11-1 to 11-n to be charged to a fully charged state and discharged to a fully discharged state, making maximum use of the capacity of the first to nth battery racks 11-1 to 11-n.

[0114] In the present invention, the control units 16, 16-1 to 16-n, and 21 may be control circuits. The control units 16, 16-1 to 16-n, and 21 may selectively include a processor, application specific integrated circuits (ASICs), other chipsets, logic circuits, registers, communication modems, data processing devices, and the like, known in the art, in order to activate the various control logics described above. When the control logic is realized by software, the control units 16, 16-1 to 16-n, and 21 may be realized by a collection of program modules. In this case, the program modules may be stored in a memory and may be activated by a processor. The memory may be present inside or outside the processor, and may be connected to the processor by various well-known computer parts. The memory may be included in the storage media 17, 17-1 to 17-n of the present invention. Furthermore, the memory refers to a collective term for devices in which information is stored, regardless of the type of device, and does not refer to a specific memory device.

[0115] At least one of the various control logics of the control units 16, 16-1 to 16-n, and 21 may be combined, and the combined control logic may be created by a computer-readable code system and recorded in a computer-readable recording medium. There is no particular limit to the type of the recording medium as long as it is accessible by a processor included in the computer. As an example, the recording medium may include at least one selected from the group including a read-only memory (ROM), a random access memory (RAM), a register, a compact disk read-only memory (CD-ROM), a magnetic tape, a hard disk, a floppy disk, and an optical data recording device. In addition, the code system may be distributed and stored and executed in computers connected by a network. Furthermore, functional programs, codes, and code segments for realizing the combined control logic may be easily inferred by a programmer in the technical field to which the present invention pertains.

[0116] In describing various embodiments of the present invention, components designated as "units" should be understood to be functionally distinct elements, not necessarily physically distinct elements. Thus, each component may be selectively integrated with other components, or each component may be divided into subcomponents for efficient execution of control logic. However, it is obvious to those skilled in the art that even if components are integrated or divided, the integrated or divided components should also be interpreted as falling within the scope of the present invention as long as the same function is recognized.

[0117] Although the present invention has been described above using limited embodiments and drawings, the technical concept of the present invention is in no way limited thereto, and it goes without saying that a person having ordinary knowledge in the technical field to which the present invention pertains can make various modifications and variations within the scope of the technical concept of the present invention and the equivalent scope of the claims. [Explanation of symbols]

[0118] 10 Management device 11. Energy storage sources 11-1~n Battery rack 12,12-1 Switch 14 Battery Cells 15 Sensor section 15-1~n Sensor section 15a Voltage measurement section 15b Current measurement section 15c Temperature measurement part 16 Control section 16-1~n Slave control unit 17 Storage medium 17-1~n Storage medium 18 Communication Interface 18-1~n Communication Interface 20 Management device 21 Master control section 22 Storage medium 23 Communication Interface

Claims

1. A sensor unit that measures an operating characteristic of the power storage source, and a control unit operably coupled to the sensor unit, The control unit is (i) acquiring operating characteristic information of the power storage source from the sensor unit to determine an operating power limit of the power storage source; (ii) determining a charging power provided from a power conversion system (PCS) or a discharging power provided to a power conversion system (PCS) side using the operating characteristic information while the power storage source is operating; (iii) interrupting the operation of the power storage source when a first interruption condition is met in which the charging power or the discharging power is greater than a preset unstable power range of the power conversion system (PCS) and the charging power or the discharging power is greater than the operating power limit by a first threshold; (iv) interrupting the operation of the power storage source when a second interruption condition is satisfied, in which the charging power or the discharging power is within a preset unstable power range of the power conversion system (PCS) and the charging power or the discharging power is equal to or greater than a second threshold value above the operating power limit; The unstable power range indicates a power range in which the accuracy of the power control of the PCS may be degraded, The second threshold is greater than the first threshold.

2. The control unit is receiving operational characteristic information including a charge / discharge current, a voltage, and a temperature of the power storage source from the sensor unit; accumulating the charge / discharge current to determine a state of charge of the power storage source; The power storage source management device of claim 1 , further comprising: a power storage source management unit that determines an operating power limit of the power storage source corresponding to the determined state of charge and the received temperature by referring to lookup information that defines a correlation between the state of charge, temperature, and an operating power limit.

3. The power storage source management device according to claim 1 , wherein the control unit is provided with information about a preset unstable power range of the power conversion system (PCS) from the power conversion system (PCS).

4. The power storage resource management device according to any one of claims 1 to 3, wherein the first threshold value is between 10% and 30% of the operating power limit.

5. The power storage resource management device according to any one of claims 1 to 3, wherein the second threshold value is between 30% and 60% of the operating power limit.

6. The power storage source management device according to claim 5 , wherein the second threshold value increases as the charging power or discharging power of the power storage source decreases.

7. The power storage source management device according to claim 1 , wherein the power storage source includes first to nth battery racks.

8. The battery rack includes first to n-th slave control units provided in the first to n-th battery racks, respectively, and a master control unit connected to the first to n-th slave control units so as to be capable of communicating with the master control units, Each of the first to nth slave control units acquires operating characteristic information of a battery rack to which the first to nth slave control units are attached from a sensor unit, determines an operating power limit and a charging power or discharging power of the battery rack using the operating characteristic information, and provides the determined operating power limit and charging power or discharging power to the master control unit; The master control unit is summing the operating power limit and the charging power or discharging power transmitted from the first to n-th slave control units to determine a total operating power limit and a total charging power or a total discharging power; When a first operation interruption condition is satisfied, the total charging power or the total discharging power is greater than a preset unstable power range of a power conversion system (PCS) and the total charging power or the total discharging power is greater than the total operating power limit by a first threshold value, the first operation interruption condition is satisfied, and an operation interruption message is provided to a first to n-th slave controller; If a second operation interruption condition is satisfied, the total charging power or the total discharging power is within a preset unstable power range of a power conversion system (PCS) and the total charging power or the total discharging power is equal to or greater than a second threshold value of the total operating power limit, providing an operation interruption message to first to n-th slave controllers; The unstable power range indicates a power range in which the accuracy of the power control of the PCS may be degraded, The second threshold is greater than the first threshold.

9. 1. A method for controlling a management device for a power storage resource, comprising: acquiring operational characteristic information of the power storage source from a sensor unit that measures an operational characteristic of the power storage source; using the operational characteristic information to determine an operational power limit for the power storage source; determining a charging power provided from a power conversion system (PCS) or a discharging power provided to a power conversion system (PCS) side using the operating characteristic information while the power storage source is operating; interrupting the operation of the power storage source when a first interruption condition is met, the first interruption condition being that the charging power or the discharging power is greater than a preset unstable power range of the power conversion system (PCS) and the charging power or the discharging power is greater than the operating power limit by a first threshold; interrupting the operation of the power storage source when a second interruption condition is met, the charging power or the discharging power being within a preset unstable power range of the power conversion system (PCS) and the charging power or the discharging power being greater than the operating power limit by a second threshold, the second threshold being greater than the first threshold; Including, The method of claim 1, wherein the unstable power range indicates a power range where accuracy of power control of the PCS may be degraded.

10. receiving operational characteristic information including a charge / discharge current, a voltage, and a temperature of the power storage source from the sensor unit; accumulating the charge / discharge current to determine a state of charge of the power storage source; determining an operating power limit of the power storage source corresponding to the determined state of charge and the received temperature by referring to lookup information that defines a correlation between the state of charge, the temperature, and an operating power limit; 10. The method of claim 9, comprising:

11. 10. The method of claim 9, further comprising the step of receiving from the power conversion system (PCS) information regarding a preset unstable power range of the PCS.

12. The method of claim 9 , wherein the first threshold is between 10% and 30% of the operating power limit.

13. The method of claim 9 , wherein the second threshold is between 30% and 60% of the operating power limit.

14. The method of claim 13 , wherein the second threshold value increases as the charging or discharging power of the power storage source becomes lower.

15. 1. A method for controlling a management device for a power storage resource, comprising: The power storage source management device includes first to nth slave control units respectively installed in the first to nth battery racks, and a master control unit connected to the first to nth slave control units so as to be communicable with the first to nth slave control units, and the method includes: Each of the first to nth slave control units acquires operational characteristic information from a sensor unit that measures operational characteristics of the battery rack to which the first to nth slave control units are attached, determines an operational power limit and a charging power or discharging power of the battery rack, and provides the determined operational power limit and charging power or discharging power to the master control unit; The master control unit sums up the operating power limit and the charging power or discharging power transmitted from the first to nth slave control units to determine a total operating power limit and a total charging power or a total discharging power; The master control unit provides an operation interruption message to the first to nth slave control units when a first operation interruption condition is satisfied, in which the total charging power or the total discharging power is greater than a preset unstable power range of a power conversion system (PCS) and the total charging power or the total discharging power is greater than the total operating power limit by a first threshold value; a step of the master control unit providing an operation interruption message to the first to nth slave control units when a second operation interruption condition is satisfied, in which the total charging power or the total discharging power is within a preset unstable power range of the power conversion system (PCS) and the total charging power or the total discharging power is equal to or greater than the total operating power limit by a second threshold value, the second threshold value being greater than the first threshold value; The first to nth slave control units interrupt the operation of the battery rack to which they are attached in response to receiving the operation interruption message; Including, The method of claim 1, wherein the unstable power range indicates a power range where accuracy of power control of the PCS may be degraded.

16. A computer program comprising instructions for causing a management device of the power storage source to carry out the method according to any one of claims 9 to 14.

17. A computer program comprising instructions for causing the power storage resource management device to carry out the method according to claim 15.

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