Control method for capacity calibration of energy storage battery

Abstract

The invention discloses a control method for capacity calibration of an energy storage battery. The control method comprises the following steps that 1, an optical storage charging equipment master controller obtains battery information reported by the energy storage battery; 2, the optical storage, charging and switching equipment master control judges whether capacity calibration of the energy storage and switching battery is carried out or not according to the battery information and the load state in a switching cabinet of the optical storage, charging and switching equipment; 3, after the optical storage charging equipment power supply module receives the optical storage charging equipment master control capacity calibration instruction, capacity calibration is executed, and capacity calibration of full discharge and full charge is carried out on the energy storage battery; and step 4, after the full-discharge capacity calibration charging process is completed, updating the latest capacity value of the energy storage battery. According to the invention, through full discharge and full charge, the electric quantity of the energy storage battery is more accurate; through reasonable utilization of the energy storage pack in the optical storage, charging and conversion device and the charging energy in the optical storage, charging and conversion device, the discharging energy in the second stage is transferred instead of being consumed, so that the whole capacity process is more energy-saving.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a control method for calibrating the capacity of an energy storage battery. Background Art

[0002] At present, the main use of photovoltaic storage and charging and swapping products is to provide energy replenishment for energy storage and swapping batteries. The sources of energy are divided into two types, one is municipal electricity, and the other is energy from photovoltaic storage.

[0003] However, after the energy storage battery is replaced by the user after replenishment, during use, the SOC has not been calibrated for a long time, and the accumulated error is large, which affects the BMS SOC integral calculation result on time, resulting in errors in the SOC calculation result. Therefore, there is a problem that the SOC jumps from a high value to 0%, which directly affects the user experience. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the above-mentioned technology and to provide a control method for calibrating the capacity of an energy storage battery.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A control method for calibrating the capacity of an energy storage battery, characterized in that it comprises the following steps:

[0007] Step 1: The main control of the solar storage charging and swapping device obtains the battery information reported by the energy storage swapping battery, and the battery information includes the number of charge and discharge cycles of the energy storage swapping battery;

[0008] Step 2: The main control of the photovoltaic charging and swapping equipment determines whether the energy storage battery needs to be calibrated according to the number of charge and discharge cycles of the energy storage battery. If yes, proceed to step 3, otherwise return to step 1;

[0009] Step 3: Determine whether to calibrate the capacity of the energy storage battery to be calibrated according to the load status in the battery cabinet of the photovoltaic storage and charging equipment. Otherwise, return to step 1. If yes, proceed to step 4. The capacity calibration of the energy storage battery to be calibrated adopts the method of full discharge and full charge, which is specifically divided into three stages: the first stage is a charging capacity calibration process, the second stage is a discharging capacity calibration process, and the third stage is a secondary charging capacity calibration process.

[0010] The method for determining whether the capacity calibration of the energy storage battery can be performed is as follows:

[0011] The time taken by the energy storage battery to be calibrated to complete the second stage is ΔT, and the capacity value of the energy storage battery currently recorded by the energy storage battery to be calibrated is C D; The energy consumed by the remaining energy storage batteries in the current photovoltaic storage and charging equipment, except for the energy storage battery to be calibrated, within the ΔT time is expected to be ΔC Sn The energy consumed by the energy storage pack in the photovoltaic storage and charging device within ΔT time is expected to be ΔC E ; then if ΔC Sn +ΔC E >C D , then calibrate the energy storage battery to be calibrated;

[0012] Step 4: After receiving the capacity calibration instruction from the main control of the photovoltaic storage and charging and swapping equipment, the power module of the photovoltaic storage and charging and swapping equipment executes capacity calibration to perform full discharge and full charge capacity calibration on the energy storage and swapping battery; wherein, in the second stage of the calibration, the energy in the energy storage and swapping battery to be calibrated is used as the energy consumption of the remaining energy storage and swapping batteries and the energy storage packs in the photovoltaic storage and charging and swapping equipment except for the energy storage and swapping battery to be calibrated;

[0013] Step 5. After completing the full capacity calibration charging process, the energy storage battery updates the latest capacity value.

[0014] Further improvements,

[0015] Where, ΔC Sn U represents the energy consumed by all energy storage batteries except the energy storage battery to be calibrated within ΔT time, n represents the number of grids except the grid where the energy storage battery to be calibrated is located, that is, the maximum number of energy storage batteries supported; U Si Represents the current charging voltage of the i-th energy storage battery; I Si represents the current charging current of the bottom i energy storage batteries; T Si represents the remaining charging time of the i-th energy storage battery. If T Si If it is greater than ΔT, then take T Si =ΔT.

[0016] 3. The control method for energy storage battery capacity calibration according to claim 1, characterized in that ΔC E =C Fe -C Le ; ΔC E : represents the available energy of the energy storage pack in the photovoltaic storage and charging equipment, C Fe Indicates the full charge capacity of the energy storage pack in the photovoltaic storage and charging equipment; C Le Indicates the remaining capacity of the energy storage pack in the solar-storage charging and swapping device.

[0017] 4. The control method for energy storage battery capacity calibration according to claim 1, characterized in that in step 2, the capacity calibration of the energy storage battery adopts a full discharge and full charge method as follows:

[0018] Phase 1: One-time charge capacity calibration process:

[0019] Charge the energy storage battery to be calibrated according to the charging voltage and charging current required by the battery until the battery capacity reaches 100%, and then proceed to the second stage;

[0020] Phase 2: Discharge Capacity Calibration Process:

[0021] The energy storage battery to be calibrated is discharged according to the set discharge current until the energy storage battery is completely discharged, and the discharge capacity of the energy storage battery from being fully charged to being completely discharged is recorded as the capacity value of the energy storage battery to be calibrated, and then the process proceeds to the third stage;

[0022] Phase 3: Secondary charging capacity calibration process:

[0023] Charge according to the charging voltage and current required by the energy storage battery to be calibrated until the battery is fully charged.

[0024] 5. The control method for energy storage battery capacity calibration as described in claim 2, characterized in that ΔT = 2h.

[0025] Further improvement, in step 3, if

[0026] ΔC Sn +ΔC E +ΔC M +ΔC C +ΔC H >C D Then calibrate the energy storage battery to be calibrated;

[0027] Where: ΔC M : Indicates the energy available to the main control system in the photovoltaic storage and charging equipment within ΔT time;

[0028] ΔC C : represents the energy available to the monitoring system in the photovoltaic storage and charging equipment within ΔT time;

[0029] ΔC H : Represents the energy available in the heat exchange system of the solar-storage-charging-swap equipment within ΔT time.

[0030] As a further improvement, in step 2, the number of charge and discharge cycles of the energy storage battery is within 640 times, and the calibration cycle interval is 1 capacity calibration every 80 times;

[0031] The number of charge and discharge cycles of the energy storage battery is between 640 and 1000 times, and the calibration cycle interval is 1 capacity calibration every 60 times;

[0032] The number of charge and discharge cycles of the energy storage battery is greater than 1000 times, and the calibration cycle interval is 1 capacity calibration every 45 times. The beneficial effects of the present invention are:

[0033] 1. By fully discharging and fully charging, the power of the energy storage battery can be made more accurate.

[0034] 2. By rationally utilizing the energy storage packs in the photovoltaic storage and charging equipment and the energy charged in the photovoltaic storage and charging equipment, the energy discharged in the second stage will be transferred instead of consumed, making the entire capacity process more energy-efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Flowchart for calibration of the present invention.

[0036] Figure 2 This is a structural diagram of the photovoltaic storage and charging and swapping equipment. DETAILED DESCRIPTION

[0037] The following is a further description of the embodiments of the present invention in conjunction with the accompanying drawings and examples. It should be noted that the examples do not limit the scope of protection claimed by the present invention.

[0038] Example 1

[0039] like Figure 1 As shown, for the energy storage battery, the main control of the photovoltaic charging and swapping equipment, and the power module of the photovoltaic charging and swapping equipment, the working process is as follows:

[0040] 1) The main control of the photovoltaic storage charging and swapping equipment reports the number of charge and discharge cycles and the number of cumulative capacity calibrations in the battery information reported by the energy storage swapping battery.

[0041] 2) Based on the battery information reported by the energy storage battery and the load status in the battery cabinet of the photovoltaic storage charging and swapping equipment, the main control of the photovoltaic storage charging and swapping equipment sends a capacity calibration instruction to the power module of the photovoltaic storage charging and swapping equipment.

[0042] 3) After receiving the capacity calibration instruction from the main control unit of the photovoltaic storage charging and swapping equipment, the power module of the photovoltaic storage charging and swapping equipment performs capacity calibration and fully discharges and fully charges the energy storage battery.

[0043] 4) After completing the full discharge and full charge process, the energy storage battery will update the latest capacity value.

[0044] The strategy for the main control of the photovoltaic storage charging and swapping equipment to determine whether to enter the capacity calibration:

[0045] Before the energy storage battery enters the capacity calibration, calculate the energy ΔC that can be consumed by all other batteries in the photovoltaic storage charging and swapping equipment within the time ΔT to complete the second stage of discharge capacity calibration Sn The energy available in the energy storage pack in the solar storage and charging equipment ΔC EIs the sum greater than the energy C required for the energy storage battery to discharge in the second stage? D If yes, it will enter the capacity calibration, otherwise it will not enter the capacity calibration and will switch to normal charging.

[0046] in:

[0047] ΔT: Determined according to the discharge capacity calibration time of the second stage, generally 2h (@0.5C discharge)

[0048] ΔC Sn : Indicates the energy that all energy storage and replacement batteries are expected to consume within ΔT time. Specific calculation method:

[0049]

[0050] Where, ΔC Sn U represents the energy consumed by all energy storage batteries except the energy storage battery to be calibrated within ΔT time, n represents the number of grids except the grid where the energy storage battery to be calibrated is located, that is, the maximum number of energy storage batteries supported; U Si Represents the current charging voltage of the i-th energy storage battery; I Si represents the current charging current of the bottom i energy storage batteries; T Si represents the remaining charging time of the i-th energy storage battery. If T Si If it is greater than ΔT, then take T Si =ΔT.

[0051] ΔC E : Indicates the energy available in the energy storage pack in the photovoltaic storage and charging equipment. Specific calculation method:

[0052] ΔC E =C Fe -C Le

[0053] Among them, C Fe Indicates the full charge capacity of the energy storage pack in the photovoltaic storage and charging equipment; C Le Indicates the remaining battery capacity.

[0054] C D : Indicates the maximum energy consumed by the energy storage battery to be calibrated in the second stage. For example, for a 4820 battery, the maximum energy consumed in the second stage is 960Wh.

[0055] Phase 1: One-time charge capacity calibration process

[0056] The battery is charged according to the required charging voltage and current until it is fully charged, and then it goes to the second stage.

[0057] Phase 2: Discharge Capacity Calibration Process (Full Discharge)

[0058] The energy storage battery to be calibrated is discharged according to the set discharge current (the default is 0.5C, which can be adjusted according to the operating conditions) until the battery is completely discharged. Then it goes to the third stage.

[0059] Stage 3: Secondary charging capacity calibration process (full charge)

[0060] The battery is charged according to the required charging voltage and current until the battery is fully charged.

[0061] In order to improve the capacity calibration rate, the available capacity is calculated before the energy storage battery enters the capacity calibration. In addition to the above-mentioned solar storage charging and swapping equipment, all other batteries can consume energy ΔC within the time ΔT to complete the second stage of discharge capacity calibration. Sn The energy available in the energy storage pack in the Heguang storage and charging equipment ΔC E It is also possible to introduce other energy within the system of the photovoltaic storage and charging equipment, such as the energy consumed by the main control system, monitoring system, and heat exchange system.

[0062] In order to maximize the use of available energy, the capacity calibration rate is improved while also saving the energy consumed during discharge capacity calibration.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A control method for calibrating the capacity of an energy storage battery, characterized in that: The following steps are involved: Step 1: The main control of the solar storage charging and swapping device obtains the battery information reported by the energy storage swapping battery, and the battery information includes the number of charge and discharge cycles of the energy storage swapping battery; Step 2: The main control of the photovoltaic charging and swapping equipment determines whether the energy storage battery needs to be calibrated according to the number of charge and discharge cycles of the energy storage battery. If yes, proceed to step 3, otherwise return to step 1; Step 3: Determine whether to calibrate the capacity of the energy storage battery to be calibrated according to the load status in the battery cabinet of the photovoltaic storage and charging equipment. Otherwise, return to step 1. If yes, proceed to step 4. The capacity calibration of the energy storage battery to be calibrated adopts the method of full discharge and full charge, which is specifically divided into three stages: the first stage is a charging capacity calibration process, the second stage is a discharging capacity calibration process, and the third stage is a secondary charging capacity calibration process. The method for determining whether the capacity calibration of the energy storage battery can be performed is as follows: The time taken by the energy storage battery to be calibrated to complete the second stage is ΔT, and the capacity value of the energy storage battery currently recorded by the energy storage battery to be calibrated is C D ; The energy consumed by the remaining energy storage batteries in the current photovoltaic storage and charging equipment, except for the energy storage battery to be calibrated, within the ΔT time is expected to be ΔC Sn The energy consumed by the energy storage pack in the photovoltaic storage and charging device within ΔT time is expected to be ΔC E ; then if ΔC Sn +ΔC E >C D , then calibrate the energy storage battery to be calibrated; Step 4: After receiving the capacity calibration instruction from the main control of the photovoltaic storage and charging and swapping equipment, the power module of the photovoltaic storage and charging and swapping equipment executes capacity calibration to perform full discharge and full charge capacity calibration on the energy storage and swapping battery; wherein, in the second stage of the calibration, the energy in the energy storage and swapping battery to be calibrated is used as the energy consumption of the remaining energy storage and swapping batteries and the energy storage packs in the photovoltaic storage and charging and swapping equipment except for the energy storage and swapping battery to be calibrated; Step 5. After completing the full capacity calibration charging process, the energy storage battery updates the latest capacity value.

2. The control method for energy storage battery capacity calibration according to claim 1, characterized in that: Where, ΔC Sn U represents the energy consumed by all energy storage batteries except the energy storage battery to be calibrated within ΔT time, n represents the number of grids except the grid where the energy storage battery to be calibrated is located, that is, the maximum number of energy storage batteries supported; U Si Represents the current charging voltage of the i-th energy storage battery; I Si represents the current charging current of the bottom i energy storage batteries; T Si represents the remaining charging time of the i-th energy storage battery. If T Si If it is greater than ΔT, then take T Si =ΔT.

3. The control method for energy storage battery capacity calibration according to claim 1, characterized in that: ΔC E =C Fe -C Le ; ΔC E : represents the available energy of the energy storage pack in the photovoltaic storage and charging equipment, C Fe Indicates the full charge capacity of the energy storage pack in the photovoltaic storage and charging equipment; C Le Indicates the remaining capacity of the energy storage pack in the solar-storage charging and swapping device.

4. The control method for energy storage battery capacity calibration according to claim 1, characterized in that: In step 2, the capacity calibration of the energy storage battery is carried out by a full discharge and full charge method as follows: Phase 1: One-time charge capacity calibration process: Charge the energy storage battery to be calibrated according to the charging voltage and charging current required by the battery until the battery capacity reaches 100%, and then proceed to the second stage; Phase 2: Discharge Capacity Calibration Process: The energy storage battery to be calibrated is discharged according to the set discharge current until the energy storage battery is completely discharged, and the discharge capacity of the energy storage battery from being fully charged to being completely discharged is recorded as the capacity value of the energy storage battery to be calibrated, and then the process proceeds to the third stage; Phase 3: Secondary charging capacity calibration process: Charge according to the charging voltage and current required by the energy storage battery to be calibrated until the battery is fully charged.

5. The control method for calibrating the capacity of an energy storage battery as claimed in claim 2, characterized in that: ΔT=2h.

6. The control method for energy storage battery capacity calibration according to claim 1, characterized in that: In step 3, if ΔC Sn +ΔC E +ΔC M +ΔC C +ΔC H >C D Then calibrate the energy storage battery to be calibrated; Where: ΔC M : Indicates the energy available to the main control system in the photovoltaic storage and charging equipment within ΔT time; ΔC C : represents the energy available to the monitoring system in the photovoltaic storage and charging equipment within ΔT time; ΔC H : Represents the energy available in the heat exchange system of the solar-storage-charging-swap equipment within ΔT time.

7. The control method for energy storage battery capacity calibration according to claim 1, characterized in that: In the step 2, the number of charge and discharge cycles of the energy storage battery is within 640 times, and the calibration cycle interval is 1 capacity calibration every 80 times; The number of charge and discharge cycles of the energy storage battery is between 640 and 1000 times, and the calibration cycle interval is 1 capacity calibration every 60 times; The number of charge and discharge cycles of the energy storage swap battery is greater than 1000 times, and the calibration cycle interval is 1 capacity calibration every 45 times.

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