An on-line battery capacity checking method and device for a distributed DC power supply system of a station

Abstract

The application discloses a kind of station with distributed DC power supply system battery on-line capacity checking method and device, comprising: when the battery in parallel power component reaches the time that needs to be checked, the output current limit value of distributed DC power supply module is calculated, and the output current limit value is sent to distributed DC power supply module;Send the instruction of stopping AC / DC unit work to distributed DC power supply module;Send given voltage value to distributed DC power supply module, and given voltage value is higher than current bus voltage value;Get the discharge current of battery, and adjust given current limit value according to discharge current;When checking parallel power component, the terminal voltage and discharge current of battery are detected, and the duration of checking capacity is recorded;When battery terminal voltage is lower than preset checking minimum voltage, end checking capacity;When battery terminal voltage is normal and checking time is equal to preset checking time, end checking capacity.On-line full capacity checking of battery is realized, and the intelligence of DC power supply system is improved.

Description

Technical Field

[0001] This invention relates to the field of power system technology, and in particular to a method and apparatus for online capacity assessment of batteries in a station-use distributed DC power supply system. Background Technology

[0002] As a crucial backup power source for DC systems, batteries directly impact the safe and reliable operation of the entire system. Performing a full-capacity discharge is an essential part of battery maintenance, determining whether the battery capacity meets system requirements. The full-capacity discharge requirement for batteries is 0.1C. 10 The battery is subjected to a verification discharge using a current, with a discharge duration not exceeding 10 hours. After discharge, the battery must be recharged. In actual operation and maintenance, most substations and power supply bureaus adopt two main methods for verification discharge: one is to use a discharge device to periodically perform half-capacity or full-capacity discharge on the battery; the other is to equip the DC system with an active inverter to perform verification discharge on the battery. The disadvantage of the first method is its low level of automation and high technical requirements for operators. With the acceleration of smart grid construction, various grid and provincial power maintenance companies have invested a lot of manpower and resources in battery verification discharge maintenance, but there are still instances of inadequate and untimely battery maintenance. The second method involves converting the battery's DC power into AC power through an active inverter and directly connecting it to the grid. This method can automate battery verification, but it places high demands on the inverter; otherwise, the connected AC power may interfere with the normal power grid, posing a risk of other problems. Summary of the Invention

[0003] The purpose of this invention is to provide a method and apparatus for online capacity verification of batteries in a station-use distributed DC power system. Without increasing the discharge circuit and battery discharge instrument of the batteries in the distributed DC power system, it achieves online full capacity verification of the batteries, improves the intelligence of the DC power system, and saves a lot of manpower and material resources.

[0004] To address the aforementioned technical problems, a first aspect of this invention provides an online capacity assessment method for a station-use distributed DC power supply system's battery. The station-use distributed DC power supply system includes: a DC bus, a DC monitoring component, and a parallel power supply component. The parallel power supply component comprises a distributed DC power supply module and a battery. The distributed DC power supply module includes: an AC / DC conversion unit, a DC / DC conversion unit, a charging DC / DC unit, a discharging DC / DC unit, a first controller, a second controller, and a communication circuit. The method includes the following steps:

[0005] When the battery in the parallel power supply assembly reaches the time when it needs to be recharged, calculate the output current limit value of the distributed DC power supply module of the parallel power supply assembly, and send the output current limit value to the distributed DC power supply module.

[0006] Send a command to the distributed DC power supply module to stop the AC / DC unit from operating;

[0007] Send a given voltage value to the distributed DC power supply module, the given voltage value being higher than the current bus voltage value;

[0008] Obtain the discharge current of the battery, and adjust the given current limit value according to the discharge current;

[0009] When calibrating the capacity of the parallel power supply assembly, the terminal voltage and discharge current of the battery are detected, and the duration of the calibration is recorded.

[0010] When the battery terminal voltage is lower than the preset minimum capacity voltage, the capacity approval process ends.

[0011] When the battery terminal voltage is normal and the capacity verification time is equal to the preset capacity verification time, the capacity verification ends.

[0012] Furthermore, the formula for calculating the output current limit value is as follows:

[0013]

[0014] Among them, U B I is the rated output voltage of the battery. 10 η is the battery discharge current value at a 10-hour rate, η is the module's conversion efficiency, and U is the DC bus voltage.

[0015] Further, the step of obtaining the discharge current of the battery and adjusting the given current limit value based on the discharge current includes:

[0016] Obtain the discharge current of the battery;

[0017] When the discharge current value is greater than the 10h rate discharge current value of the battery, the given current limit value is reduced.

[0018] When the discharge current value is less than the 10h rate discharge current value of the battery, the given current limit value is increased.

[0019] Furthermore, before calculating the output current limiting value of the distributed DC power supply module of the parallel power supply assembly, the method further includes:

[0020] Determine whether the parallel power supply assembly meets the capacity requirements;

[0021] If satisfied, then proceed with the step of calculating the output current limit value of the distributed DC power supply module of the parallel power supply assembly;

[0022] If the requirements are not met, the nuclear capacity will be terminated.

[0023] Accordingly, a second aspect of the present invention provides an online capacity assessment device for a station-use distributed DC power system battery. The station-use distributed DC power system includes: a DC bus, a DC monitoring component, and a parallel power supply component. The parallel power supply component consists of a distributed DC power module and a battery. The distributed DC power module includes: an AC / DC conversion unit, a DC / DC conversion unit, a charging DC / DC unit, a discharging DC / DC unit, a first controller, a second controller, and a communication circuit.

[0024] The first calculation module is used to calculate the output current limit value of the distributed DC power supply module of the parallel power supply assembly when the battery in the parallel power supply assembly reaches the time when it needs to be recharged, and send the output current limit value to the distributed DC power supply module.

[0025] The first control module is used to send a command to the distributed DC power supply module to stop the AC / DC unit from operating;

[0026] The second control module is used to send a given voltage value to the distributed DC power supply module, the given voltage value being higher than the current bus voltage value;

[0027] The second calculation module is used to obtain the discharge current of the battery and adjust the given current limit value according to the discharge current.

[0028] The data detection module detects the terminal voltage and discharge current of the battery when the parallel power supply assembly is being rated, and records the duration of the rating.

[0029] The third control module is used to terminate the capacity approval process when the battery terminal voltage is lower than the preset minimum capacity voltage.

[0030] The third control module is also used to end the capacity verification when the battery terminal voltage is normal and the capacity verification time is equal to the preset capacity verification time.

[0031] Furthermore, the formula for calculating the output current limit value is as follows:

[0032]

[0033] Among them, U B I is the rated output voltage of the battery. 10 η is the battery discharge current value at a 10-hour rate, η is the module's conversion efficiency, and U is the DC bus voltage.

[0034] Furthermore, the second computing module includes:

[0035] A calculation unit is used to obtain the discharge current of the battery;

[0036] A first control unit is configured to reduce the given current limit value when the discharge current value is greater than the 10-hour rate discharge current value of the battery.

[0037] The first control unit is also configured to increase the given current limit value when the discharge current value is less than the 10h rate discharge current value of the battery.

[0038] Furthermore, the online capacity assessment device for the station-use distributed DC power system battery also includes: a capacity assessment module, the capacity assessment module comprising:

[0039] A judgment unit is used to determine whether the parallel power supply assembly meets the capacity requirements;

[0040] The second control unit is used to perform the step of calculating the output current limit value of the distributed DC power supply module of the parallel power supply component when the parallel power supply component meets the capacity limit condition;

[0041] The second control unit is also configured to terminate the capacity approval process when the parallel power supply assembly fails to meet the capacity approval conditions.

[0042] Accordingly, a third aspect of the present invention provides an electronic device, including: at least one processor; and a memory connected to the at least one processor; wherein the memory stores instructions executable by the processor, the instructions being executed by the processor to cause the at least one processor to perform the above-described method for online capacity assessment of batteries in a station distributed DC power system.

[0043] Accordingly, a fourth aspect of the present invention provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-described method for online capacity verification of batteries in a station-use distributed DC power supply system.

[0044] The above-described technical solutions of the embodiments of the present invention have the following beneficial technical effects:

[0045] Without adding a battery discharge circuit or battery discharger to the distributed DC power system, online full-capacity verification of the battery was achieved, improving the intelligence of the DC power system and saving a lot of manpower and resources. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the station-use distributed DC power supply system provided in an embodiment of the present invention;

[0047] Figure 2 This is a schematic diagram of the distributed DC power supply module provided in an embodiment of the present invention;

[0048] Figure 3 This is a flowchart of the online capacity approval method for a station-use distributed DC power supply system battery provided in an embodiment of the present invention;

[0049] Figure 4 This is a logic diagram of the online capacity approval method for the battery of a station-use distributed DC power supply system provided in an embodiment of the present invention;

[0050] Figure 5 This is a block diagram of the online capacity verification device module for the battery of the station-use distributed DC power supply system provided in an embodiment of the present invention;

[0051] Figure 6 This is a block diagram of the second computing module provided in an embodiment of the present invention;

[0052] Figure 7 This is a block diagram of the capacity determination module provided in an embodiment of the present invention.

[0053] Figure label:

[0054] 1. First calculation module; 2. First control module; 3. Second control module; 4. Second calculation module; 41. Calculation unit; 42. First control unit; 5. Data detection module; 6. Third control module; 7. Capacity judgment module; 71. Judgment unit; 72. Second control unit. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0056] Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 The first aspect of this invention provides an online capacity verification method for a station-use distributed DC power system battery. The station-use distributed DC power system includes: a DC bus, a DC monitoring component, and a parallel power supply component. The parallel power supply component consists of a distributed DC power module and a battery. The distributed DC power module includes: an AC / DC conversion unit, a DC / DC conversion unit, a charging DC / DC unit, a discharging DC / DC unit, a first controller, a second controller, and a communication circuit. The method includes the following steps:

[0057] S200: When the battery in the parallel power supply component reaches the time when it needs to be recharged, calculate the output current limit value of the distributed DC power supply module of the parallel power supply component and send the output current limit value to the distributed DC power supply module.

[0058] S300 sends a command to the distributed DC power supply module to stop the AC / DC unit from operating.

[0059] S400 sends a given voltage value to the distributed DC power supply module. The given voltage value is higher than the current bus voltage value.

[0060] S500 obtains the battery discharge current and adjusts the given current limit value based on the discharge current.

[0061] The S600 detects the battery terminal voltage and discharge current when calibrating the capacity of parallel power supply components, and records the duration of the calibrated capacity.

[0062] S700: When the battery terminal voltage is lower than the preset minimum capacity voltage, the capacity verification ends.

[0063] S800: When the battery terminal voltage is normal and the capacity verification time is equal to the preset capacity verification time, the capacity verification ends.

[0064] Compared to traditional station DC power systems, distributed DC power systems fundamentally solve the inherent problem of a single battery failure affecting the entire battery pack. They also enable uninterrupted replacement of parallel power components, and allow for smooth and simple system expansion, significantly improving the safety, reliability, and flexibility of the DC power supply system. However, due to the limited widespread use of distributed DC power systems, research on online battery capacity assessment for this system is scarce. The method proposed in this invention addresses the implementation of online battery capacity assessment in distributed DC power systems.

[0065] The AC input of the distributed DC power module is converted into 220V or 110V DC power by the AC / DC conversion unit and the DC / DC conversion unit to supply power to the load. Simultaneously, the battery is charged via the charging DC / DC unit, and the battery voltage is boosted to the DC output via the discharging DC / DC unit, maintaining a hot backup state. In the event of AC power failure or battery capacity adjustment, the battery supplies power to the DC output load via the discharging DC / DC unit, ensuring uninterrupted power supply.

[0066] The DC monitoring component is responsible for receiving the status and information of the modules and batteries uploaded by the distributed DC power supply module, judging the status of the entire system, and performing online capacity discharge of the battery by issuing output voltage and current setpoints and capacity discharge commands to the distributed DC power supply module when the capacity conditions are met. It also ensures that the battery can be fully capacity-controlled by dynamically adjusting the output current setpoint.

[0067] Specifically, in step S200, the formula for calculating the output current limit value is as follows:

[0068]

[0069] Among them, U B I is the rated output voltage of the battery. 10 η is the battery discharge current value at a 10-hour rate, η is the module's conversion efficiency, and U is the DC bus voltage.

[0070] Further, in step S500, obtaining the battery's discharge current and adjusting the given current limit value based on the discharge current includes:

[0071] S510 obtains the battery discharge current.

[0072] S520: When the discharge current value is greater than the battery's 10h rate discharge current value, the given current limit value is reduced.

[0073] S530: When the discharge current value is less than the battery's 10-hour rate discharge current value, the given current limit value is increased.

[0074] Furthermore, before calculating the output current limiting value of the distributed DC power supply module of the parallel power supply components in step S200, the following steps are also included:

[0075] S110, determine whether the parallel power supply components meet the capacity requirements.

[0076] S120, if satisfied, then proceed with the step of calculating the output current limit value of the distributed DC power supply module of the parallel power supply components.

[0077] If S130 is not met, then the nuclear capacity will be terminated.

[0078] The above technical solution achieves online battery capacity verification through the cooperation of DC monitoring components, distributed DC power modules, and batteries, replacing the traditional battery maintenance and management mode that relies on external discharge instruments, thus saving a significant amount of manpower and resources.

[0079] Accordingly, please refer to Figure 5 A second aspect of the present invention provides an online capacity assessment device for a station-use distributed DC power system battery. The station-use distributed DC power system includes: a DC bus, a DC monitoring component, and a parallel power supply component. The parallel power supply component consists of a distributed DC power module and a battery. The distributed DC power module includes: an AC / DC conversion unit, a DC / DC conversion unit, a charging DC / DC unit, a discharging DC / DC unit, a first controller, a second controller, and a communication circuit.

[0080] The first calculation module 1 is used to calculate the output current limit value of the distributed DC power supply module of the parallel power supply component when the battery in the parallel power supply component reaches the time when it needs to be re-capacitated, and send the output current limit value to the distributed DC power supply module.

[0081] The first control module 2 is used to send a command to the distributed DC power supply module to stop the AC / DC unit from operating;

[0082] The second control module 3 is used to send a given voltage value to the distributed DC power supply module. The given voltage value is higher than the current bus voltage value.

[0083] The second calculation module 4 is used to obtain the discharge current of the battery and adjust the given current limit value according to the discharge current.

[0084] Data detection module 5 detects the battery terminal voltage and discharge current during the capacity verification of parallel power supply components and records the duration of capacity verification.

[0085] The third control module 6 is used to terminate the capacity approval process when the battery terminal voltage is lower than the preset minimum capacity voltage.

[0086] The third control module 6 is also used to end the capacity verification when the battery terminal voltage is normal and the capacity verification time is equal to the preset capacity verification time.

[0087] Furthermore, the formula for calculating the output current limit value is as follows:

[0088]

[0089] Among them, U B I is the rated output voltage of the battery. 10 η is the battery discharge current value at a 10-hour rate, η is the module's conversion efficiency, and U is the DC bus voltage.

[0090] Further, please refer to Figure 6 The second calculation module 4 includes:

[0091] The calculation unit 41 is used to obtain the discharge current of the storage battery;

[0092] The first control unit 42 is used to reduce the given current limit value when the discharge current value is greater than the 10h rate discharge current value of the battery.

[0093] The control unit 42 is also used to increase the given current limit value when the discharge current value is less than the 10h rate discharge current value of the battery.

[0094] Further, please refer to Figure 7 The station-use distributed DC power system battery online capacity assessment device also includes: a capacity assessment module 7, which includes:

[0095] Judgment unit 71 is used to determine whether the parallel power supply components meet the capacity requirements;

[0096] The second control unit 72 is used to perform the step of calculating the output current limit value of the distributed DC power supply module of the parallel power supply component when the parallel power supply component meets the capacity conditions.

[0097] The second control unit 72 is also used to terminate the capacity verification when the parallel power supply assembly fails to meet the capacity verification conditions.

[0098] Accordingly, a third aspect of the present invention provides an electronic device, including: at least one processor; and a memory connected to the at least one processor; wherein the memory stores instructions executable by the processor, the instructions being executed by the processor to cause the at least one processor to perform the above-described method for online capacity assessment of batteries in a station distributed DC power system.

[0099] Accordingly, a fourth aspect of the present invention provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-described method for online capacity verification of batteries in a station-use distributed DC power supply system.

[0100] The embodiments of the present invention aim to protect an online capacity assessment method and apparatus for batteries in a station-use distributed DC power supply system, which has the following effects:

[0101] Without adding a battery discharge circuit or battery discharger to the distributed DC power system, online full-capacity verification of the battery was achieved, improving the intelligence of the DC power system and saving a lot of manpower and resources.

[0102] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0103] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0104] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0105] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for online capacity verification of batteries in a station-use distributed DC power supply system, characterized in that, The station's distributed DC power supply system includes: a DC bus, DC monitoring components, and parallel power supply components. The parallel power supply components consist of distributed DC power modules and batteries. Each distributed DC power module includes: an AC / DC conversion unit, a DC / DC conversion unit, a charging DC / DC unit, a discharging DC / DC unit, a first controller, a second controller, and a communication circuit. The system includes the following steps: When the battery in the parallel power supply assembly reaches the time when it needs to be recharged, calculate the output current limit value of the distributed DC power supply module of the parallel power supply assembly, and send the output current limit value to the distributed DC power supply module. Send a command to the distributed DC power supply module to stop the AC / DC unit from operating; Send a given voltage value to the distributed DC power supply module, the given voltage value being higher than the current bus voltage value; Obtain the discharge current of the battery, and adjust the given current limit value according to the discharge current; When calibrating the capacity of the parallel power supply assembly, the terminal voltage and discharge current of the battery are detected, and the duration of the calibration is recorded. When the battery terminal voltage is lower than the preset minimum capacity voltage, the capacity approval process ends. When the battery terminal voltage is normal and the capacity verification time is equal to the preset capacity verification time, the capacity verification ends. The formula for calculating the output current limit value is as follows: ; Among them, U B I is the rated output voltage of the battery. 10 η is the battery discharge current value at a 10-hour rate, η is the module's conversion efficiency, and U is the DC bus voltage.

2. The method for online capacity verification of batteries in a station-use distributed DC power supply system according to claim 1, characterized in that, The step of obtaining the discharge current of the battery and adjusting the given current limit value based on the discharge current includes: Obtain the discharge current of the battery; When the discharge current value is greater than the 10h rate discharge current value of the battery, the given current limit value is reduced. When the discharge current value is less than the 10h rate discharge current value of the battery, the given current limit value is increased.

3. The method for online capacity verification of batteries in a station-use distributed DC power supply system according to claim 1, characterized in that, Before calculating the output current limiting value of the distributed DC power supply module of the parallel power supply assembly, the method further includes: Determine whether the parallel power supply assembly meets the capacity requirements; If satisfied, then proceed with the step of calculating the output current limit value of the distributed DC power supply module of the parallel power supply assembly; If the requirements are not met, the nuclear capacity will be terminated.

4. An online capacity assessment device for storage batteries in a station-use distributed DC power supply system, characterized in that, The station's distributed DC power supply system includes: a DC bus, DC monitoring components, and parallel power supply components. The parallel power supply components consist of distributed DC power modules and batteries. Each distributed DC power module includes: an AC / DC conversion unit, a DC / DC conversion unit, a charging DC / DC unit, a discharging DC / DC unit, a first controller, a second controller, and a communication circuit. The first calculation module is used to calculate the output current limit value of the distributed DC power supply module of the parallel power supply assembly when the battery in the parallel power supply assembly reaches the time when it needs to be recharged, and send the output current limit value to the distributed DC power supply module. The first control module is used to send a command to the distributed DC power supply module to stop the AC / DC unit from operating; The second control module is used to send a given voltage value to the distributed DC power supply module, the given voltage value being higher than the current bus voltage value; The second calculation module is used to obtain the discharge current of the battery and adjust the given current limit value according to the discharge current. The data detection module detects the terminal voltage and discharge current of the battery when the parallel power supply assembly is being rated, and records the duration of the rating. The third control module is used to terminate the capacity approval process when the battery terminal voltage is lower than the preset minimum capacity voltage. The third control module is also used to end the capacity verification when the battery terminal voltage is normal and the capacity verification time is equal to the preset capacity verification time; The formula for calculating the output current limit value is as follows: ; Among them, U B I is the rated output voltage of the battery. 10 η is the battery discharge current value at a 10-hour rate, η is the module's conversion efficiency, and U is the DC bus voltage.

5. The online capacity verification device for the battery of the station-use distributed DC power system according to claim 4, characterized in that, The second calculation module includes: A calculation unit is used to obtain the discharge current of the battery; A first control unit is configured to reduce the given current limit value when the discharge current value is greater than the 10-hour rate discharge current value of the battery. The first control unit is also configured to increase the given current limit value when the discharge current value is less than the 10h rate discharge current value of the battery.

6. The online capacity verification device for the battery of the station-use distributed DC power system according to claim 4, characterized in that, Also includes: The capacity determination module includes: A judgment unit is used to determine whether the parallel power supply assembly meets the capacity requirements; The second control unit is used to perform the step of calculating the output current limit value of the distributed DC power supply module of the parallel power supply component when the parallel power supply component meets the capacity limit condition; The second control unit is also configured to terminate the capacity approval process when the parallel power supply assembly fails to meet the capacity approval conditions.

7. An electronic device, characterized in that, include: At least one processor; And a memory connected to the at least one processor; wherein the memory stores instructions executable by the processor, the instructions being executed by the processor to cause the at least one processor to perform the online capacity approval method for a station-use distributed DC power system battery as described in any one of claims 1-3.

8. A computer-readable storage medium, characterized in that, It stores computer instructions that, when executed by a processor, implement the online capacity verification method for the battery of a station-use distributed DC power system as described in any one of claims 1-3.

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