Battery PACK switchable energy storage system

Abstract

The invention relates to the field of energy storage systems, in particular to an energy storage system with a switchable battery PACK. The technical problems that according to an energy storage system in the prior art, the number of PACKs in a battery cabinet is basically fixed and cannot be switched, the same PCS can only conduct charging and discharging circulation on a small number of PACKs, the utilization rate of the PCS is low, when a certain PACK is in an undervoltage or overvoltage state, use of other PACKs can be affected, and therefore the service life of the whole battery cabinet is affected are solved. According to the technical scheme, the battery PACK switchable energy storage system comprises an energy storage module, a battery management module, a PACK management module, an energy monitoring module, an energy management module and a cloud platform; according to the intelligent control system capable of freely switching the battery PACKs, more PACKs are accommodated in the battery cabinet, and a fixed number of PACKs are selected to be put into the charge-discharge cycle of the energy storage system according to a PACK scheduling algorithm, so that the use number of PCSs is reduced, the utilization rate of the PCSs is improved, and the cost of the whole energy storage system is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the field of energy storage systems, and in particular to an energy storage system with switchable battery PACKs. Background Art

[0002] At present, the number of battery PACKs in a single battery cabinet or DC cabinet is fixed, and the number of batteries in each PACK is also fixed. The batteries in the PACK are basically connected in series, and the PACKs are also connected in series. In the small and medium-sized energy storage systems used in industry and commerce, the total voltage of all PACKs connected in series is between several hundred volts and more than one thousand volts, and the power is generally between tens of kilowatts and hundreds of kilowatts. Generally, a single battery cabinet or multiple battery cabinets are equipped with a bidirectional converter, referred to as PCS. PCS is located between the battery cabinet and the power grid or load, and is a device that realizes the bidirectional conversion of electric energy. The PCS can be used to invert the DC power of the battery cabinet into AC power and transmit it to the power grid or use it for AC loads, or to rectify the AC power of the power grid into DC power to charge the battery. In the entire energy storage system, the PCS is the core and the most valuable equipment; however, the energy storage system under the existing technology basically has a fixed number of battery PACKs in a battery cabinet and cannot be switched. The same PCS can only charge and discharge a small number of PACKs, and the PCS utilization rate is low. In addition, when a PACK is in an undervoltage or overvoltage state, it will affect the use of other PACKs, thereby affecting the service life of the entire battery cabinet. Summary of the invention

[0003] For energy storage systems under existing technologies, the number of battery PACKs in a battery cabinet is basically fixed and cannot be switched. The same PCS can only charge and discharge a small number of PACKs, and the PCS utilization rate is low. When a PACK is in an undervoltage or overvoltage state, it will affect the use of other PACKs, thereby affecting the service life of the entire battery cabinet.

[0004] The technical solution of the present invention is: a battery PACK switchable energy storage system, comprising:

[0005] Energy storage module, used to store electric energy through combined batteries and provide continuous power supply to other equipment;

[0006] The battery management module is used to collect the cell voltage and temperature in the energy storage module and upload the collected data to the PACK management module;

[0007] PACK management module, used to collect the total battery voltage of the battery cabinet, collect the charge and discharge current, collect the insulation resistance of the positive and negative electrodes of the battery, collect the battery power, calculate the battery life, and transmit the data to the energy monitoring module;

[0008] Energy monitoring module, used to monitor the operating status of each device in the battery cabinet, control the temperature balance, charging and discharging process and charging and discharging power in the battery cabinet, and report the collected data to the energy management module;

[0009] Energy management module, which is used to complete fault management, energy management, scheduling and real-time monitoring of the energy storage system, transmit the collected data to the cloud platform through 4G communication equipment, and receive instructions issued by the cloud platform;

[0010] The cloud platform is used to receive data transmitted by the energy management module, analyze the data, and issue control instructions to the energy management module through 4G communication equipment.

[0011] Preferably, the energy storage module includes a battery PACK, which is composed of multiple battery cells connected in series. The battery PACK is used to store electrical energy and provide continuous power supply to other devices. When the external power supply has surplus electrical energy, the battery PACK in the energy storage module will absorb the electrical energy and convert it into chemical energy and store it in the battery cells. This process is achieved through the electrochemical reaction inside the battery. When charging, the current passes through the battery, so that the chemical reaction inside the battery is reversed, generating chemical energy for storage; when energy needs to be released, the battery PACK completes the chemical reaction through the internal electrolyte, converts the stored chemical energy into electrical energy, and transmits it to the external device through the electrical system. The energy storage module can provide continuous and stable power supply to other devices.

[0012] Preferably, the battery management module includes a BMU battery management unit, which collects the voltage and temperature of the battery cells in the PACK and sends the data to the PACK management module; the battery management module includes the following steps when working:

[0013] S101: The BMU monitors the voltage of each cell in the battery PACK in real time through a high-precision voltage sensor or acquisition circuit;

[0014] S202: The temperature sensor built into the BMU can continuously monitor the temperature of the battery cell and the surrounding environment to ensure that the battery operates within a suitable temperature range;

[0015] S203: The BMU filters and calibrates the collected cell voltage and temperature data;

[0016] S204: The BMU uploads the processed data such as the cell voltage and temperature to the PACK management module in real time through the CAN bus.

[0017] Preferably, the PACK management module includes a BMS, which is a battery PACK management unit. The BMS calculates the voltage and power of each PACK through the voltage and temperature data of each battery cell reported by the BMU, and reports the data to the energy monitoring module.

[0018] Preferably, the PACK management module includes the following steps when operating:

[0019] S301: After receiving the data, the BMS verifies the data integrity, rationality and timeliness to ensure that the received data is valid and undamaged;

[0020] S302: filtering the voltage and temperature data of each battery cell to remove noise and abnormal values ​​and improve the accuracy of the data;

[0021] S303: Evaluate the health status (SOH) of each battery cell based on the voltage and temperature data, combined with the historical data of the battery cell and the specification parameters provided by the manufacturer;

[0022] S304: Add the voltages of all the cells to obtain the total voltage of the entire PACK;

[0023] S305: using the voltage and temperature of the battery cell and a pre-established battery model, i.e., an open circuit voltage-capacity relationship model, the remaining capacity SOC of each battery cell is estimated, and the remaining capacity of the entire PACK is calculated according to the capacity of the battery cell and the parallel and series relationship;

[0024] S306: Summarize the calculated total voltage, power SOC, health status SOH and other key parameters of the PACK;

[0025] S307: Upload the packaged data to the energy monitoring module via the communication interface CAN bus.

[0026] Preferably, the energy monitoring module includes an EMU energy management unit and a PCS power conversion unit. The EMU energy management unit is used to monitor the operating status of various devices in the battery cabinet, including the BMS battery management system, the PCS power conversion unit, the air conditioner, the electric meter and various sensors. The PCS power conversion unit bidirectional converter is located between the battery cabinet and the power grid or the load. It is a device for realizing bidirectional conversion of electric energy. It can invert the DC power of the battery cabinet into AC power and transmit it to the power grid or use it for the AC load. It can also rectify the AC power of the power grid into DC power to charge the battery. The EMU energy management unit ensures the temperature balance, charging and discharging process and reasonable distribution of charging and discharging power in the battery cabinet through precise control strategies. The EMU energy management unit cuts the PACK that meets the requirements into the power circuit in real time before the PCS charging and discharging is started or during the charging and discharging process according to the voltage and power of each PACK.

[0027] Preferably, the energy monitoring module performs power switching in the discharge state including the following steps:

[0028] S401: Measure PACK battery voltage and temperature;

[0029] S402: Calculate the power of each PACK;

[0030] S403: Determine whether there are cells with low voltage or power and large deviation in the PACK; if the determination result is yes, proceed to S404; if the determination result is no, proceed to S405;

[0031] S404: exclude the battery cells with low voltage or power and large deviation from the discharge power circuit, and re-enter S401;

[0032] S405: Selecting a fixed number of PACKs with similar voltages or electrical quantities;

[0033] S406: Switch the selected PACK and connect it in series to the power loop;

[0034] S407: Start the PCS to start discharging the battery;

[0035] S408: Determine whether the discharge time or the discharge cut-off voltage is satisfied; if the determination result is yes, proceed to S409; if the determination result is no, proceed to S410;

[0036] S409: Stop PCS and end battery discharge;

[0037] S410: Measure the PACK battery voltage and temperature; and re-enter S408.

[0038] Preferably, the energy monitoring module performs power switching in the charging state including the following steps:

[0039] S501: Measure PACK battery voltage and temperature;

[0040] S502: Calculate the power of each PACK;

[0041] S503: Determine whether there are cells with high voltage or power and large deviation in the PACK; if the determination result is yes, proceed to S504; if the determination result is no, proceed to S505;

[0042] S504: exclude the battery cells with higher voltage or power and larger deviation from the discharge power circuit, and re-enter S501;

[0043] S505: Select a fixed number of PACKs with similar voltages or electrical quantities;

[0044] S506: Switch the selected PACK and connect it in series to the power loop;

[0045] S507: Start the PCS to start charging the battery;

[0046] S508: Determine whether the charging time or the charging cut-off voltage is met; if the determination result is yes, proceed to S509; if the determination result is no, proceed to S510;

[0047] S509: Stop PCS and end battery charging;

[0048] S510: Measure the PACK battery voltage and temperature; and re-enter S508.

[0049] Preferably, when the energy monitoring module uses a power relay with a single-pole double-throw switch to perform PACK switching circuit operation, the following steps are included:

[0050] S601: Connect one end of the positive and negative electrodes of each PACK battery pack to the common end of the power relay; connect the other end of the PACK battery pack to the normally closed contact of the relay; connect the PACK bypass loop to the normally open contact of the relay;

[0051] S602: Set the initial state of the relay. The common terminal of the relay is connected to the normally closed contact by default to ensure that the PACK battery pack is normally connected to the circuit;

[0052] S603: When switching the PACK battery pack or connecting to the bypass circuit, current is applied to the relay coil through a signal from the BMS system;

[0053] S604: After the coil is energized, the magnetic circuit system generates a magnetic field to attract the contact return spring, so that the contact switches from the normally closed contact to the normally open contact; the positive or negative pole of the PACK battery pack is connected to the bypass circuit, and the PACK battery pack is bypassed;

[0054] S605: When it is necessary to restore the normal connection of the PACK battery pack, the current of the relay coil is cut off again through the control signal, and the contact is restored to the normally closed state under the action of the return spring, and the PACK battery pack is reconnected to the circuit;

[0055] When the energy monitoring module uses an electronic transistor to perform a PACK switching circuit operation, the following steps are included:

[0056] S701: Select appropriate PMOS tubes according to the current and voltage requirements of the PACK and bypass. Each pair of electronic switches consists of two PMOS tubes connected back to back to ensure that no matter which end has a higher voltage, the current will not flow back. The first pair of PMOS tubes is connected to the positive electrode of the PACK, and the second pair of PMOS tubes is connected to the bypass.

[0057] S702: Introduce two control signals to respectively control the electronic switch of the positive electrode of PACK, namely ControlPACK, and the electronic switch of the bypass, namely ControlBYPASS;

[0058] S703: Use a logic NAND gate circuit NAND Gate to ensure that the two control signals are not high at the same time;

[0059] S704: ControlPACK and ControlBYPASS are used as two inputs of a NAND gate; when any one of the inputs is high, the output of the NAND gate is low; the output is high only when both inputs are low;

[0060] S705: Adjust the output to adapt to the PMOS drive. Since the PMOS tube is turned off at a high level and turned on at a low level, a NOT gate or a logic inversion circuit is used to invert the output of the NOT gate to obtain a correct driving signal. Assuming that the output of the NAND gate is low, it means "safe", that is, it will not be turned on at the same time, then it is converted to a high level through the NOT gate to turn off the PMOS tube. When the output of the NAND gate is high, it is avoided by logic.

[0061] S706: Monitor and control the ControlPACK and ControlBYPASS through the microcontroller MCU so that they will not be set to high level at the same time;

[0062] S707: Connecting the adjusted driving signal to the gates of each pair of PMOS tubes respectively;

[0063] S708: When ControlPACK is high and ControlBYPASS is low, the electronic switch of the positive electrode of PACK is turned on, and PACK is connected to the circuit; conversely, when ControlBYPASS is high and ControlPACK is low, the electronic switch of the bypass is turned on, and PACK is bypassed;

[0064] Preferably, a relay is used to switch the PACK. When the PACK switching is completed, the main positive relay and the main negative relay on the DC bus of the battery cabinet are energized, the PCS is started, and charging and discharging begin. To avoid the relay from being stuck due to the relay being energized under a high current state, the PACK must not be switched when there is a large current on the DC bus of the battery cabinet during the charging and discharging process. While using an electronic transistor switching method, because the switching speed of the electron tube is fast and there is no relay sticking phenomenon, the PACK switching can be completed before charging and discharging, or the PACK can be switched dynamically in real time during the charging and discharging process according to actual needs, thereby ensuring the continuity of the charging and discharging circuit power.

[0065] Preferably, the energy management module includes an EMS energy management module, which is used to monitor the status parameters of each component inside the energy storage system in real time, such as voltage, current, temperature, insulation resistance, etc.; once abnormal data or parameters deviating from the normal range are detected, the EMS will immediately trigger the fault diagnosis mechanism; based on real-time data analysis and historical data comparison, the EMS can predict potential failure risks and issue early warning signals in advance; the EMS reports the collected data to the cloud platform in real time through wireless communication means such as 4G communication equipment, and receives control instructions and parameter settings issued by the cloud.

[0066] Beneficial effects of the present invention:

[0067] 1. In the energy storage system under the prior art, the number of battery PACKs in a battery cabinet is basically fixed and cannot be switched. The same PCS can only charge and discharge a small number of PACKs, and the PCS utilization rate is low. When a certain PACK is in an undervoltage or overvoltage state, it will affect the use of other PACKs, thereby affecting the service life of the entire battery cabinet. The present invention accommodates a larger number of PACKs in the battery cabinet through an intelligent control system in which the battery PACKs can be freely switched. According to the PACK scheduling algorithm, a fixed number of PACKs are selected to be put into the charge and discharge cycle of the energy storage system, thereby reducing the number of PCSs used, improving the utilization rate of PCSs, and significantly reducing the cost of the entire energy storage system.

[0068] 2. The BMS calculates the voltage and power of each PACK based on the voltage and temperature data of each battery cell reported by the BMU, and reports the data to the EMU. Based on the voltage and power of each PACK, the EMU cuts the PACK that meets the requirements into the power circuit in real time before the PCS starts charging and discharging or during the charging and discharging process, thereby accommodating more PACKs in the battery cabinet, reducing the number of PCSs used, increasing the utilization rate of PCSs, and significantly reducing the cost of the entire energy storage system.

[0069] 3. By adopting the method of switching PACK by relays, when the PACK switching is completed, the main positive relay and the main negative relay on the DC bus of the battery cabinet are energized, the PCS is started, and charging and discharging begin. In order to avoid the relay being energized under high current state and causing the relay to stick, during the charging and discharging process, when there is a large current on the DC bus of the battery cabinet, the PACK must not be switched; by adopting the method of switching by electronic transistors, because the switching speed of the electron tube is fast and there is no relay sticking phenomenon, the PACK switching can be completed before charging and discharging according to actual needs, or the PACK can be switched dynamically in real time during the charging and discharging process, thereby ensuring the continuity of the charging and discharging circuit power. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1The internal topology diagram of the energy storage system with switchable battery PACK of the present invention is shown;

[0071] Figure 2 Shown is a schematic diagram of a single-pole double-throw switch PACK switching circuit of a battery PACK switchable energy storage system of the present invention;

[0072] Figure 3 Shown is a schematic diagram of a switching circuit of an electronic transistor switch PACK of an energy storage system with a switchable battery PACK according to the present invention;

[0073] Figure 4 Shown is a schematic diagram of the charging state PACK switching process of the energy storage system with switchable battery PACK of the present invention;

[0074] Figure 5 Shown is a schematic diagram of the discharge state PACK switching process of the battery PACK switchable energy storage system of the present invention. DETAILED DESCRIPTION

[0075] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0076] See also Figure 1-5 The present invention provides an embodiment: a battery PACK switchable energy storage system, comprising:

[0077] Energy storage module, used to store electric energy through combined batteries and provide continuous power supply to other equipment;

[0078] The battery management module is used to collect the cell voltage and temperature in the energy storage module and upload the collected data to the PACK management module;

[0079] PACK management module, used to collect the total battery voltage of the battery cabinet, collect the charge and discharge current, collect the insulation resistance of the positive and negative electrodes of the battery, collect the battery power, calculate the battery life, and transmit the data to the energy monitoring module;

[0080] Energy monitoring module, used to monitor the operating status of each device in the battery cabinet, control the temperature balance, charging and discharging process and charging and discharging power in the battery cabinet, and report the collected data to the energy management module;

[0081] Energy management module, which is used to complete fault management, energy management, scheduling and real-time monitoring of the energy storage system, transmit the collected data to the cloud platform through 4G communication equipment, and receive instructions issued by the cloud platform;

[0082] The cloud platform is used to receive data transmitted by the energy management module, analyze the data, and issue control instructions to the energy management module through 4G communication equipment.

[0083] Preferably, the energy storage module includes a battery PACK, which is composed of multiple battery cells connected in series. The battery PACK is used to store electrical energy and provide continuous power supply to other devices. When the external power supply has surplus electrical energy, the battery PACK in the energy storage module will absorb the electrical energy and convert it into chemical energy and store it in the battery cells. This process is achieved through the electrochemical reaction inside the battery. When charging, the current passes through the battery, so that the chemical reaction inside the battery is reversed, generating chemical energy for storage; when energy needs to be released, the battery PACK completes the chemical reaction through the internal electrolyte, converts the stored chemical energy into electrical energy, and transmits it to the external device through the electrical system. The energy storage module can provide continuous and stable power supply to other devices.

[0084] Preferably, the battery management module includes a BMU battery management unit, which collects the voltage and temperature of the battery cells in the PACK and sends the data to the PACK management module; the battery management module includes the following steps when working:

[0085] S101: The BMU monitors the voltage of each cell in the battery PACK in real time through a high-precision voltage sensor or acquisition circuit;

[0086] S202: The temperature sensor built into the BMU can continuously monitor the temperature of the battery cell and the surrounding environment to ensure that the battery operates within a suitable temperature range;

[0087] S203: The BMU filters and calibrates the collected cell voltage and temperature data;

[0088] S204: The BMU uploads the processed data such as the cell voltage and temperature to the PACK management module in real time via the CAN bus.

[0089] Preferably, the PACK management module includes a BMS, which is a battery PACK management unit. The BMS calculates the voltage and power of each PACK through the voltage and temperature data of each battery cell reported by the BMU, and reports the data to the energy monitoring module.

[0090] Preferably, the PACK management module includes the following steps when operating:

[0091] S301: After receiving the data, the BMS verifies the data integrity, rationality and timeliness to ensure that the received data is valid and undamaged;

[0092] S302: filtering the voltage and temperature data of each battery cell to remove noise and abnormal values ​​and improve the accuracy of the data;

[0093] S303: Evaluate the health status (SOH) of each battery cell based on the voltage and temperature data, combined with the historical data of the battery cell and the specification parameters provided by the manufacturer;

[0094] S304: Add the voltages of all the cells to obtain the total voltage of the entire PACK;

[0095] S305: using the voltage and temperature of the battery cell and a pre-established battery model, i.e., an open circuit voltage-capacity relationship model, the remaining capacity SOC of each battery cell is estimated, and the remaining capacity of the entire PACK is calculated according to the capacity of the battery cell and the parallel and series relationship;

[0096] S306: Summarize the calculated total voltage, power SOC, health status SOH and other key parameters of the PACK;

[0097] S307: Upload the packaged data to the energy monitoring module via the communication interface CAN bus.

[0098] Preferably, the energy monitoring module includes an EMU energy management unit and a PCS power conversion unit. The EMU energy management unit is used to monitor the operating status of various devices in the battery cabinet, including the BMS battery management system, the PCS power conversion unit, the air conditioner, the electric meter and various sensors. The PCS power conversion unit bidirectional converter is located between the battery cabinet and the power grid or the load. It is a device for realizing bidirectional conversion of electric energy. It can invert the DC power of the battery cabinet into AC power and transmit it to the power grid or use it for the AC load. It can also rectify the AC power of the power grid into DC power to charge the battery. The EMU energy management unit ensures the temperature balance, charging and discharging process and reasonable distribution of charging and discharging power in the battery cabinet through precise control strategies. The EMU energy management unit cuts the PACK that meets the requirements into the power circuit in real time before the PCS charging and discharging is started or during the charging and discharging process according to the voltage and power of each PACK.

[0099] Preferably, the energy monitoring module performs power switching in the discharge state including the following steps:

[0100] S401: Measure PACK battery voltage and temperature;

[0101] S402: Calculate the power of each PACK;

[0102] S403: Determine whether there are cells with low voltage or power and large deviation in the PACK; if the determination result is yes, proceed to S404; if the determination result is no, proceed to S405;

[0103] S404: exclude the battery cells with low voltage or power and large deviation from the discharge power circuit, and re-enter S401;

[0104] S405: Selecting a fixed number of PACKs with similar voltages or electrical quantities;

[0105] S406: Switch the selected PACK and connect it in series to the power loop;

[0106] S407: Start the PCS to start discharging the battery;

[0107] S408: Determine whether the discharge time or the discharge cut-off voltage is satisfied; if the determination result is yes, proceed to S409; if the determination result is no, proceed to S410;

[0108] S409: Stop PCS and end battery discharge;

[0109] S410: Measure the PACK battery voltage and temperature; and re-enter S408.

[0110] Preferably, the energy monitoring module performs power switching in the charging state including the following steps:

[0111] S501: Measure PACK battery voltage and temperature;

[0112] S502: Calculate the power of each PACK;

[0113] S503: Determine whether there are cells with high voltage or power and large deviation in the PACK; if the determination result is yes, proceed to S504; if the determination result is no, proceed to S505;

[0114] S504: exclude the battery cells with higher voltage or power and larger deviation from the discharge power circuit, and re-enter S501;

[0115] S505: Select a fixed number of PACKs with similar voltages or electrical quantities;

[0116] S506: Switch the selected PACK and connect it in series to the power loop;

[0117] S507: Start the PCS to start charging the battery;

[0118] S508: Determine whether the charging time or the charging cut-off voltage is met; if the determination result is yes, proceed to S509; if the determination result is no, proceed to S510;

[0119] S509: Stop PCS and end battery charging;

[0120] S510: Measure the PACK battery voltage and temperature; and re-enter S508.

[0121] Preferably, when the energy monitoring module uses a power relay with a single-pole double-throw switch to perform PACK switching circuit operation, the following steps are included:

[0122] S601: Connect one end of the positive and negative electrodes of each PACK battery pack to the common end of the power relay; connect the other end of the PACK battery pack to the normally closed contact of the relay; connect the PACK bypass loop to the normally open contact of the relay;

[0123] S602: Set the initial state of the relay. The common terminal of the relay is connected to the normally closed contact by default to ensure that the PACK battery pack is normally connected to the circuit;

[0124] S603: When switching the PACK battery pack or connecting to the bypass circuit, current is applied to the relay coil through a signal from the BMS system;

[0125] S604: After the coil is energized, the magnetic circuit system generates a magnetic field to attract the contact return spring, so that the contact switches from the normally closed contact to the normally open contact; the positive or negative pole of the PACK battery pack is connected to the bypass circuit, and the PACK battery pack is bypassed;

[0126] S605: When it is necessary to restore the normal connection of the PACK battery pack, the current of the relay coil is cut off again through the control signal, and the contact is restored to the normally closed state under the action of the return spring, and the PACK battery pack is reconnected to the circuit;

[0127] When the energy monitoring module uses an electronic transistor to perform a PACK switching circuit operation, the following steps are included:

[0128] S701: Select appropriate PMOS tubes according to the current and voltage requirements of the PACK and bypass. Each pair of electronic switches consists of two PMOS tubes connected back to back to ensure that no matter which end has a higher voltage, the current will not flow back. The first pair of PMOS tubes is connected to the positive electrode of the PACK, and the second pair of PMOS tubes is connected to the bypass.

[0129] S702: Introduce two control signals to respectively control the electronic switch of the positive electrode of PACK, namely ControlPACK, and the electronic switch of the bypass, namely ControlBYPASS;

[0130] S703: Use a logic NAND gate circuit NAND Gate to ensure that the two control signals are not high at the same time;

[0131] S704: ControlPACK and ControlBYPASS are used as two inputs of a NAND gate; when any one of the inputs is high, the output of the NAND gate is low; the output is high only when both inputs are low;

[0132] S705: Adjust the output to adapt to the PMOS drive. Since the PMOS tube is turned off at a high level and turned on at a low level, a NOT gate or a logic inversion circuit is used to invert the output of the NOT gate to obtain a correct driving signal. Assuming that the output of the NAND gate is low, it means "safe", that is, it will not be turned on at the same time, then it is converted to a high level through the NOT gate to turn off the PMOS tube. When the output of the NAND gate is high, it is avoided by logic.

[0133] S706: Monitor and control the ControlPACK and ControlBYPASS through the microcontroller MCU so that they will not be set to high level at the same time;

[0134] S707: Connecting the adjusted driving signal to the gates of each pair of PMOS tubes respectively;

[0135] S708: When ControlPACK is high and ControlBYPASS is low, the electronic switch of the positive electrode of PACK is turned on, and PACK is connected to the circuit; conversely, when ControlBYPASS is high and ControlPACK is low, the electronic switch of the bypass is turned on, and PACK is bypassed;

[0136] Preferably, a relay is used to switch the PACK. When the PACK switching is completed, the main positive relay and the main negative relay on the DC bus of the battery cabinet are energized, the PCS is started, and charging and discharging begin. To avoid the relay from being stuck due to the relay being energized under a high current state, the PACK must not be switched when there is a large current on the DC bus of the battery cabinet during the charging and discharging process. While using an electronic transistor switching method, because the switching speed of the electron tube is fast and there is no relay sticking phenomenon, the PACK switching can be completed before charging and discharging, or the PACK can be switched dynamically in real time during the charging and discharging process according to actual needs, thereby ensuring the continuity of the charging and discharging circuit power.

[0137] Preferably, the energy management module includes an EMS energy management module, which is used to monitor the status parameters of each component inside the energy storage system in real time, such as voltage, current, temperature, insulation resistance, etc.; once abnormal data or parameters deviating from the normal range are detected, the EMS will immediately trigger the fault diagnosis mechanism; based on real-time data analysis and historical data comparison, the EMS can predict potential failure risks and issue early warning signals in advance; the EMS reports the collected data to the cloud platform in real time through wireless communication means such as 4G communication equipment, and receives control instructions and parameter settings issued by the cloud; this makes the operation and management of the energy storage system more flexible and convenient.

[0138] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of those skilled in the art without departing from the spirit of the present invention.

Claims

1. A battery PACK switchable energy storage system, Features: Included are: Energy storage module, used to store electric energy through combined batteries and provide continuous power supply to other equipment; The battery management module is used to collect the cell voltage and temperature in the energy storage module and upload the collected data to the PACK management module; PACK management module, used to collect the total battery voltage of the battery cabinet, collect the charge and discharge current, collect the insulation resistance of the positive and negative electrodes of the battery, collect the battery power, calculate the battery life, and transmit the data to the energy monitoring module; Energy monitoring module, used to monitor the operating status of each device in the battery cabinet, control the temperature balance, charging and discharging process and charging and discharging power in the battery cabinet, and report the collected data to the energy management module; Energy management module, which is used to complete fault management, energy management, scheduling and real-time monitoring of the energy storage system, transmit the collected data to the cloud platform through 4G communication equipment, and receive instructions issued by the cloud platform; The cloud platform is used to receive data transmitted by the energy management module, analyze the data, and issue control instructions to the energy management module through 4G communication equipment.

2. A battery PACK switchable energy storage system according to claim 1, Features: The energy storage module includes a battery PACK, which is composed of multiple battery cells connected in series. The battery PACK stores electrical energy and provides continuous power supply to other devices. When the external power supply has surplus electrical energy, the battery PACK in the energy storage module will absorb the electrical energy and convert it into chemical energy and store it in the battery cells. This process is achieved through the electrochemical reaction inside the battery. When charging, the current passes through the battery, which reverses the chemical reaction inside the battery and generates chemical energy for storage. When energy needs to be released, the battery PACK completes the chemical reaction through the internal electrolyte, converts the stored chemical energy into electrical energy, and transmits it to external devices through the electrical system. The energy storage module can provide continuous and stable power supply to other devices.

3. A battery PACK switchable energy storage system according to claim 1, Features: The battery management module includes a BMU battery management unit. The BMU collects the voltage and temperature of the battery cells in the PACK and sends the data to the PACK management module. The battery management module includes the following steps when working: S101: The BMU monitors the voltage of each cell in the battery PACK in real time through a high-precision voltage sensor or acquisition circuit; S202: The temperature sensor built into the BMU can continuously monitor the temperature of the battery cell and the surrounding environment to ensure that the battery operates within a suitable temperature range; S203: The BMU filters and calibrates the collected cell voltage and temperature data; S204: The BMU uploads the processed data such as the cell voltage and temperature to the PACK management module in real time through the CAN bus.

4. A battery PACK switchable energy storage system according to claim 1, Features: The PACK management module includes a BMS, which is a battery PACK management unit. The BMS calculates the voltage and power of each PACK through the voltage and temperature data of each battery cell reported by the BMU, and reports the data to the energy monitoring module.

5. A battery PACK switchable energy storage system according to claim 4, It is characterized by: The PACK management module includes the following steps when working: S301: After receiving the data, the BMS verifies the data integrity, rationality and timeliness to ensure that the received data is valid and undamaged; S302: filtering the voltage and temperature data of each battery cell to remove noise and abnormal values ​​and improve the accuracy of the data; S303: Evaluate the health status (SOH) of each battery cell based on the voltage and temperature data, combined with the historical data of the battery cell and the specification parameters provided by the manufacturer; S304: Add the voltages of all the cells to obtain the total voltage of the entire PACK; S305: using the voltage and temperature of the battery cell and a pre-established battery model, i.e., an open circuit voltage-capacity relationship model, the remaining capacity SOC of each battery cell is estimated, and the remaining capacity of the entire PACK is calculated according to the capacity of the battery cell and the parallel and series relationship; S306: Summarize the calculated total voltage, power SOC, health status SOH and other key parameters of the PACK; S307: Upload the packaged data to the energy monitoring module via the communication interface CAN bus.

6. A battery PACK switchable energy storage system according to claim 1, Features: The energy monitoring module includes an EMU energy management unit and a PCS power conversion unit. The EMU energy management unit is used to monitor the operating status of each device in the battery cabinet, including the BMS battery management system, the PCS power conversion unit, air conditioning, electric meters, and various sensors. The PCS power conversion unit bidirectional converter is located between the battery cabinet and the power grid or load. It is a device for realizing bidirectional conversion of electric energy. It can convert the DC power of the battery cabinet into AC power and transmit it to the power grid or use it for AC loads. It can also rectify the AC power of the power grid into DC power to charge the battery. The EMU energy management unit uses precise control strategies to ensure the temperature balance, charging and discharging process, and reasonable distribution of charging and discharging power in the battery cabinet. The EMU energy management unit cuts the PACK that meets the requirements into the power circuit in real time before the PCS charging and discharging is started or during the charging and discharging process according to the voltage and power of each PACK.

7. A battery PACK switchable energy storage system according to claim 6, Features: The energy monitoring module performs power switching in the discharge state including the following steps: S401: Measure PACK battery voltage and temperature; S402: Calculate the power of each PACK; S403: Determine whether there is a battery cell in the PACK with low voltage or power and large deviation; If the judgment result is yes, go to S404; if the judgment result is no, go to S405; S404: exclude the battery cells with low voltage or power and large deviation from the discharge power circuit, and re-enter S401; S405: Selecting a fixed number of PACKs with similar voltages or electrical quantities; S406: Switch the selected PACK and connect it in series to the power loop; S407: Start the PCS to start discharging the battery; S408: Determine whether the discharge time or the discharge cut-off voltage is satisfied; If the judgment result is yes, proceed to S409; If the judgment result is no, proceed to S410; S409: Stop PCS and end battery discharge; S410: measuring PACK battery voltage and temperature; And re-enter S408.

8. A battery PACK switchable energy storage system according to claim 6, Features: The energy monitoring module performs power switching in the charging state including the following steps: S501: Measure PACK battery voltage and temperature; S502: Calculate the power of each PACK; S503: Determine whether there is a cell with a high voltage or power and a large deviation in the PACK; If the judgment result is yes, go to S504; if the judgment result is no, go to S505; S504: exclude the battery cells with higher voltage or power and larger deviation from the discharge power circuit, and re-enter S501; S505: Select a fixed number of PACKs with similar voltages or electrical quantities; S506: Switch the selected PACK and connect it in series to the power loop; S507: Start the PCS to start charging the battery; S508: Determine whether the charging time or the charging cut-off voltage is met; if the determination result is yes, proceed to S509; if the determination result is no, proceed to S510; S509: Stop PCS and end battery charging; S510: Measure the PACK battery voltage and temperature; and re-enter S508.

9. A battery PACK switchable energy storage system according to claim 6, Features: When the energy monitoring module uses a power relay with a single-pole double-throw switch to perform PACK switching circuit operation, the following steps are included: S601: Connect one end of the positive and negative electrodes of each PACK battery pack to the common end of the power relay; connect the other end of the PACK battery pack to the normally closed contact of the relay; connect the PACK bypass loop to the normally open contact of the relay; S602: Set the initial state of the relay. The common terminal of the relay is connected to the normally closed contact by default to ensure that the PACK battery pack is normally connected to the circuit; S603: When switching the PACK battery pack or connecting to the bypass circuit, current is applied to the relay coil through a signal from the BMS system; S604: After the coil is energized, the magnetic circuit system generates a magnetic field to attract the contact return spring, so that the contact switches from the normally closed contact to the normally open contact; the positive or negative pole of the PACK battery pack is connected to the bypass circuit, and the PACK battery pack is bypassed; S605: When it is necessary to restore the normal connection of the PACK battery pack, the current of the relay coil is cut off again through the control signal, and the contact is restored to the normally closed state under the action of the return spring, and the PACK battery pack is reconnected to the circuit; When the energy monitoring module uses an electronic transistor to perform a PACK switching circuit operation, the following steps are included: S701: Select appropriate PMOS tubes according to the current and voltage requirements of the PACK and bypass. Each pair of electronic switches consists of two PMOS tubes connected back to back to ensure that no matter which end has a higher voltage, the current will not flow back. The first pair of PMOS tubes is connected to the positive electrode of the PACK, and the second pair of PMOS tubes is connected to the bypass. S702: Introduce two control signals to respectively control the electronic switch of the positive electrode of PACK, namely ControlPACK, and the electronic switch of the bypass, namely ControlBYPASS; S703: Use a logic NAND gate circuit NAND Gate to ensure that the two control signals are not high at the same time; S704: ControlPACK and ControlBYPASS are used as two inputs of a NAND gate; when any one of the inputs is high, the output of the NAND gate is low; the output is high only when both inputs are low; S705: Adjust the output to adapt to the PMOS drive. Since the PMOS tube is turned off at a high level and turned on at a low level, a NOT gate or a logic inversion circuit is used to invert the output of the NOT gate to obtain a correct drive signal. Assuming that the output of the NAND gate is low, it means "safe", that is, it will not be turned on at the same time, then it is converted to a high level through the NOT gate to turn off the PMOS tube. When the output of the NAND gate is high, it is avoided by logic. S706: Monitor and control the ControlPACK and ControlBYPASS through the microcontroller MCU so that they will not be set to high level at the same time; S707: Connecting the adjusted driving signal to the gates of each pair of PMOS tubes respectively; S708: When ControlPACK is high and ControlBYPASS is low, the electronic switch at the positive electrode of PACK is turned on, and PACK is connected to the circuit; conversely, when ControlBYPASS is high and ControlPACK is low, the electronic switch of the bypass is turned on, and PACK is bypassed.

10. A battery PACK switchable energy storage system according to claim 1, Features: The energy management module includes the EMS energy management module, which is used to monitor the status parameters of each component inside the energy storage system in real time, such as voltage, current, temperature, insulation resistance, etc.; once abnormal data is detected or parameters deviate from the normal range, the EMS will immediately trigger the fault diagnosis mechanism; based on real-time data analysis and historical data comparison, the EMS can predict potential failure risks and issue early warning signals in advance; the EMS reports the collected data to the cloud platform in real time through wireless communication means such as 4G communication equipment, and receives control instructions and parameter settings issued by the cloud.

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