Battery parallel management device, system and method

Abstract

The present application relates to a battery parallel management device, system and method. The battery parallel management device includes a current sampler, a control unit, a variable AC source, a first solenoid, a second solenoid and a rectifying unit; the input end of the current sampler is connected to the output end of the device, the output end of the current sampler is connected to the input end of the control unit, the output end of the control unit is connected to the control end of the variable AC source, the output end of the variable AC source is connected to the first solenoid, the first solenoid and the second solenoid are coaxially wound, the second solenoid is connected to the input end of the rectifying unit, and the output end of the rectifying unit is the output end of the device.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly to a battery parallel management device, system, and method. Background Art

[0002] The capacity of a single battery is limited and its usage time is very short. Currently, multiple batteries are usually connected in parallel to expand the battery capacity, improve the overall capacity of the battery, and extend the usage time of the battery.

[0003] In traditional technologies, multiple batteries are first connected in series to form a cluster of batteries, and then multiple clusters of batteries are connected in parallel to form a battery system.

[0004] The voltages of the battery clusters in the battery system are the same, but the internal resistances of the battery clusters are different, so the currents of the battery clusters are also different. The current differences between the battery clusters cause charge and discharge between the battery clusters, resulting in premature battery failure, shortening the service life of the battery, and reducing the usability of the entire battery system. Summary of the Invention

[0005] Based on this, in view of the technical problem that when batteries are connected in parallel, due to the internal resistance difference, the current difference causes different charge and discharge currents of each battery, and further shortens the service life of the battery system, it is necessary to provide a battery parallel management device, system, and method that can balance the charge and discharge currents of parallel batteries.

[0006] A battery parallel management device, the device includes a current sampler, a control unit, a variable AC source, a first solenoid, a second solenoid, and a rectification unit; the input end of the current sampler is connected to the output end of the device, the output end of the current sampler is connected to the input end of the control unit, the output end of the control unit is connected to the control end of the variable AC source, the output end of the variable AC source is connected to the first solenoid, the first solenoid and the second solenoid are wound coaxially, the second solenoid is connected to the input end of the rectification unit, and the output end of the rectification unit is the output end of the device; wherein, the current sampler is used to collect the output signal current value of the device; the control unit is used to obtain the current average value according to the output signal current value of the device, and generate an adjustment voltage value according to the difference between the output signal current value of the device and the current average value; the variable AC source is used to generate an AC signal according to the adjustment voltage value; the first solenoid is used to access the AC signal and generate a changing magnetic field; the second solenoid is used to generate an induced current signal in the changing magnetic field; the rectification unit is used to convert the induced current signal into a DC signal and output it.

[0007] In one embodiment, the control unit includes a communication interface, a calculator, a static memory, and a data selector. The output terminals of the communication interface and the current sampler are respectively connected to the input terminal of the calculator. The output terminal of the calculator is connected to the control terminal of the data selector. The static memory is connected to the input terminal of the data selector. The output terminal of the data selector is connected to the input terminal of the variable AC source. Wherein, the communication interface is configured to receive the output signal current value of other devices; the calculator is configured to calculate the current average value of the output signal current value of other devices and the output signal current value of the device, and the difference between the output signal current value of the device and the current average value; the static memory is configured to store the correspondence table between the difference and the adjustment voltage value; the data selector is configured to generate the corresponding adjustment voltage value DSP chip and communication circuit based on the correspondence table according to the difference calculated by the calculator.

[0008] In one embodiment, the control unit includes a communication interface, a calculator, a static memory, and a data selector. The output terminals of the communication interface and the current sampler are respectively connected to the input terminal of the calculator. The output terminal of the calculator is connected to the control terminal of the data selector. The static memory is connected to the input terminal of the data selector. The output terminal of the data selector is connected to the input terminal of the variable AC source. Wherein, the communication interface is configured to send the output signal current value of the device and receive the current average value obtained according to the output signal current value of the device; the calculator is configured to calculate the difference between the output signal current value of the device and the current average value; the static memory is configured to store the correspondence table between the difference and the adjustment voltage value; the data selector is configured to generate the corresponding adjustment voltage value based on the correspondence table according to the difference calculated by the calculator.

[0009] In one embodiment, the variable AC source includes: a signal generator, connected to the control unit, for generating a pulse width modulation signal according to the adjustment voltage value; a DC power supply, for providing a DC signal; an inverter bridge circuit, respectively connected to the signal generator and the DC power supply, for converting the DC signal into an AC signal under the control of the pulse width modulation signal.

[0010] In one embodiment, the variable AC source includes: a signal generator, connected to the control unit, for generating a pulse width modulation signal according to the adjustment voltage value; a rectifier circuit, for converting the external AC input into a DC output to provide a DC signal; an inverter bridge circuit, respectively connected to the signal generator and the rectifier circuit, for converting the DC signal into an AC signal under the control of the pulse width modulation signal.

[0011] In one embodiment, the device includes: a metal core, and the first solenoid and the second solenoid are coaxially wound around the metal core.

[0012] In one embodiment, the winding directions of the first solenoid and the second solenoid coaxially wound can be the same or opposite.

[0013] In one embodiment, the rectifying unit includes a first switching tube S1, a second switching tube S2, a third switching tube S3, a fourth switching tube S4, a second capacitor C2, and a DSP chip. The control terminals of the first switching tube S1, the second switching tube S2, the third switching tube S3, and the fourth switching tube S4 are respectively connected to the DSP chip. The first ends of the first switching tube S1 and the third switching tube S3 are respectively connected to the first end of the second capacitor C2. The second end of the third switching tube S3 is connected to the first end of the fourth switching tube S4. The second end of the first switching tube S1 is connected to the first end of the second switching tube S2. The second ends of the second switching tube S2 and the fourth switching tube S4 are respectively connected to the second end of the second capacitor C2. Both ends of the second capacitor C2 are respectively connected to the DSP chip.

[0014] A battery parallel management system includes a plurality of devices. Each device includes a current sampler, a control unit, a variable AC source, a first solenoid, a second solenoid, and a rectifying unit. The input end of the current sampler is connected to the output end of the device. The output end of the current sampler is connected to the input end of the control unit. The output end of the control unit is connected to the control terminal of the variable AC source. The output end of the variable AC source is connected to the first solenoid. The first solenoid and the second solenoid are coaxially wound. The second solenoid is connected to the input end of the rectifying unit. The output end of the rectifying unit is the output end of the device. Wherein, the current sampler is used to collect the output signal current value of the device. The control unit is used to obtain the current average value according to the output signal current value of the device, and generate an adjustment voltage value according to the difference between the output signal current value of the device and the current average value. The variable AC source is used to generate an AC signal according to the adjustment voltage value. The first solenoid is used to access the AC signal and generate a changing magnetic field. The second solenoid is used to generate an induced current signal in the changing magnetic field. The rectifying unit is used to convert the induced current signal into a DC signal and output it. The control units of the plurality of devices are connected through a communication bus to realize data exchange between the control units of the plurality of devices.

[0015] A battery parallel management method includes: respectively collecting the current values of each branch where each battery cluster in multiple parallel-connected battery clusters is located; calculating the average current value based on the current values of the branches where the multiple parallel-connected battery clusters are located; and injecting a DC signal into each branch where a battery cluster is located according to the difference between the current value of each branch where a battery cluster is located and the average current value, so that the current value of each branch where a battery cluster is located is equal to the average current value.

[0016] In the above parallel management device, system and method, each battery parallel management device corresponds to each of the parallel-connected battery clusters one by one. The current sampler in the device collects the current of the corresponding battery cluster, and the control unit in the device is connected to the current sampler and can calculate the average current value according to the current values collected by the current samplers in each device, so as to obtain the average current value of the parallel-connected battery clusters. The control unit of each device generates an adjustment voltage value according to the difference between the current value collected by the current sampler in the device and the average current value, and transmits the adjustment voltage value to the connected variable AC source, and can control the variable AC source to generate a corresponding AC signal according to the adjustment voltage value. The first solenoid is connected to the variable AC source and can receive this AC signal to generate a changing magnetic field. The second solenoid is wound coaxially with the first solenoid and can generate an induced current signal in the changing magnetic field. The rectification unit is connected to the second solenoid and can convert this induced current signal into a DC signal for output. The output DC signal is converted from the induced current signal, the induced current signal is generated in the magnetic field generated by the AC signal, and the AC signal is generated according to the difference between the current value of the battery cluster and the average current value. Therefore, by outputting this DC signal to the battery cluster, the current value of the battery cluster can be adjusted to the average current value, so that the current values of each battery cluster are the same average current value, enabling the currents of each battery cluster to reach equilibrium, effectively avoiding charge and discharge between each battery cluster, thereby prolonging the service life of the battery and improving the usability of the entire battery system. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic structural diagram of a battery parallel management device in an embodiment;

[0019] Figure 2 It is a schematic structural diagram of a control unit in an embodiment;

[0020] Figure 3 It is a schematic structural diagram of a variable AC source in an embodiment;

[0021] Figure 4 Schematic diagram of the structure of another variable AC source in an embodiment;

[0022] Figure 5 Schematic diagram of a winding method of a first solenoid and a second solenoid in an embodiment;

[0023] Figure 6 Schematic diagram of another winding method of a first solenoid and a second solenoid in an embodiment;

[0024] Figure 7 Schematic diagram of yet another winding method of a first solenoid and a second solenoid in an embodiment;

[0025] Figure 8 Schematic diagram of yet another winding method of a first solenoid and a second solenoid in an embodiment;

[0026] Figure 9 Schematic diagram of the structure of a rectification unit in an embodiment;

[0027] Figure 10 Schematic diagram of the structure of another rectification unit in an embodiment;

[0028] Figure 11 Schematic diagram of the structure of a battery parallel management system in an embodiment;

[0029] Figure 12 Flowchart of a battery parallel management method in an embodiment;

[0030] Explanation of reference numerals: 10 - current sampler, 11 - input terminal, 12 - output terminal, 20 - control unit, 21 - input terminal, 22 - output terminal, 24 - communication interface, 25 - calculator, 26 - static memory, 27 - data selector, 30 - variable AC source, 32 - output terminal, 33 - control terminal, 34 - signal generator, 35 - DC power supply, 36 - inverter bridge circuit, 37 - rectification circuit, 41 - first solenoid, 42 - second solenoid, 50 - rectification unit, 51 - input terminal, 52 - output terminal, 100 - device, 200 - battery cluster, 300 - communication bus. Detailed implementation manners

[0031] For ease of understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. Embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the disclosure of the present application is more thorough and comprehensive.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0033] It can be understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, the first resistor can be referred to as the second resistor, and similarly, the second resistor can be referred to as the first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0034] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediate element. In addition, in the following embodiments, "connection", if there is a transfer of electrical signals or data between the connected objects, should be understood as "connection", "communication connection", etc.

[0035] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprise / include" or "have" etc. specify the presence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the related listed items.

[0036] As described in the background art, there is a problem of short service life when multiple battery clusters are used in parallel in the prior art. After research by the inventor, it is found that the reason for this problem is that when the battery clusters are in parallel, the voltages of the battery clusters are the same, but the internal resistances of the battery clusters are different, resulting in different currents in the battery clusters. The battery clusters will charge and discharge each other, causing the batteries in the battery clusters to fail prematurely, thus shortening the service life of the batteries and reducing the availability of the entire battery system.

[0037] For the above reasons, the present invention provides a battery parallel management device, system and method to evenly regulate the charging and discharging currents of the parallel battery clusters, so that the charging currents of the individual battery clusters are equal, thereby increasing the availability of the entire battery system and extending the life of the entire battery system.

[0038] In one embodiment, as Figure 1As shown, a battery parallel management device is provided. The device includes a current sampler 10, a control unit 20, a variable AC source 30, a first solenoid 41, a second solenoid 42, and a rectification unit 50. The input terminal 11 of the current sampler 10 is connected to the output terminal of the device, the output terminal 12 of the current sampler 10 is connected to the input terminal 21 of the control unit 20, the output terminal 22 of the control unit 20 is connected to the control terminal 33 of the variable AC source 30, the output terminal 32 of the variable AC source 30 is connected to the first solenoid 41, the first solenoid 41 and the second solenoid 42 are coaxially wound, the second solenoid 42 is connected to the input terminal 51 of the rectification unit 50, and the output terminal 52 of the rectification unit 50 is the output terminal of the device. Among them, the current sampler 10 is used to collect the output signal current value of the device. The control unit 20 is used to obtain the average current value according to the output signal current value of the device, and generate an adjustment voltage value according to the difference between the output signal current value of the device and the average current value. The variable AC source 30 is used to generate an AC signal according to the adjustment voltage value. The first solenoid 41 is used to access the AC signal and generate a changing magnetic field. The second solenoid 42 is used to generate an induced current signal in the changing magnetic field. The rectification unit 50 is used to convert the induced current signal into a DC signal and output it.

[0039] Among them, both the first solenoid 41 and the second solenoid 42 are multi-wound wires, and the internal space of the wire winding is hollow. The first solenoid 41 and the second solenoid 42 are coaxially wound, which is equivalent to the wires of the first solenoid 41 and the second solenoid 42 being wound on the same mandrel.

[0040] In this embodiment, each battery parallel management device can be corresponding to each parallel-connected battery cluster one by one. The current of the corresponding battery cluster is collected by the current sampler in the device. The control unit in the device is connected to the current sampler and can calculate the average current value based on the current values collected by the current samplers in each device, so as to obtain the average current value of the parallel-connected battery clusters. The control unit of each device generates an adjustment voltage value according to the difference between the current value collected by the current sampler in the device and the average current value, and transmits the adjustment voltage value to the connected variable AC source, so as to control the variable AC source to generate a corresponding AC signal according to the adjustment voltage value. The first solenoid is connected to the variable AC source and can access this AC signal to generate a changing magnetic field. The second solenoid and the first solenoid are coaxially wound and can generate an induced current signal in the changing magnetic field. The rectifying unit is connected to the second solenoid and can convert this induced current signal into a DC signal for output. The output DC signal is converted from the induced current signal, and the induced current signal is generated in the magnetic field generated by the AC signal. The AC signal is generated according to the difference between the current value of the battery cluster and the average current value. Therefore, by outputting this DC signal to the battery cluster, the current value of the battery cluster can be adjusted to the average current value, so that the current values of each battery cluster are the same average current value, making the currents of each battery cluster reach equilibrium, effectively avoiding charge and discharge between each battery cluster, thereby prolonging the service life of the battery and improving the usability of the entire battery system.

[0041] Exemplarily, the current sampler 10 may include a current sensor and an analog-to-digital converter. The input end of the analog-to-digital converter is connected to the current sensor, and the output end of the analog-to-digital converter is connected to the control unit 20.

[0042] Exemplarily, the current sensor is a Hall current sensor.

[0043] In practical applications, the control units 20 in each device are connected through a communication bus. One of the control units 20 in a device can be set as the host through bus arbitration, and the control units 20 in other devices are set as slaves. Each slave sends the current value collected by the current sampler 10 in the device where it is located to the host through the communication bus. The host calculates the average current value based on the current values collected by the current samplers 10 in each device and sends the calculated average current value to each slave through the communication bus, so as to obtain the average current value according to the output signal current value of the device.

[0044] During bus arbitration, arbitration numbers and arbitrators can be set in each control unit 20. When a control unit 20 has a bus request, it sends the arbitration number of this control unit 20 to the communication bus, and the arbitrator of this control unit 20 compares the arbitration number on the communication bus with the arbitration number of this control unit 20. If the arbitration number of this control unit 20 is less than the arbitration number on the communication bus, the bus request of this control unit 20 is not responded to, and this control unit 20 withdraws its arbitration number from the communication bus. Finally, the control unit 20 corresponding to the arbitration number remaining on the communication bus is the host.

[0045] In one embodiment, as Figure 2 shown, the control unit 20 includes a communication interface 24, a calculator 25, a static memory 26, and a data selector 27. The output terminal 12 of the communication interface 24 and the current sampler 10 are respectively connected to the input terminal of the calculator 25. The output terminal of the calculator 25 is connected to the control terminal of the data selector 27. The static memory 26 is connected to the input terminal of the data selector 27. The output terminal of the data selector 27 is connected to the input terminal of the variable AC source 30.

[0046] Among them, the input terminal of the calculator 25 is the input terminal 21 of the control unit 20, and the output terminal of the data selector 27 is the output terminal 22 of the control unit 20.

[0047] When the control unit 20 is the host, the communication interface 24 is used to receive the output signal current value of other devices. The calculator 25 is used to calculate the current average value of the output signal current value of other devices and the output signal current value of this device, as well as the difference between the output signal current value of this device and the current average value. The static memory 26 is used to store the correspondence table between the difference and the adjustment voltage value. The data selector 27 is used to generate the corresponding adjustment voltage value based on the correspondence table according to the difference calculated by the calculator 25.

[0048] When the control unit 20 is a slave, the communication interface 24 is used to send the output signal current value of this device and receive the current average value obtained according to the output signal current value of this device. The calculator 25 is used to calculate the difference between the output signal current value of the device and the current average value. The static memory 26 is used to store the correspondence table between the difference and the adjustment voltage value. The data selector 27 is used to generate the corresponding adjustment voltage value based on the correspondence table according to the difference calculated by the calculator 25.

[0049] In this embodiment, the control unit 20 can communicate with the control units 20 in other devices through the communication interface 24, receive the output signal current values collected by the current sampler 10 in other devices, or send the output signal current values collected by the current sampler 10 in its own device to other devices. For the host, after collecting the output signal current values collected by the current sampler 10 in each device, the calculator 25 can calculate the average current value and send the average current value to each slave through the communication interface 24. For the slave, it can directly receive through the communication interface 24 to obtain the average current value. For both the host and the slave, the calculator 25 can calculate the difference between the output signal current value collected by the current sampler 10 in its own device and the average current value. A corresponding table of the difference and the adjustment voltage value is stored in the static memory 26. Based on the difference calculated by the calculator 25, the data selector can look up the corresponding table in the static memory 26 to generate the adjustment voltage value corresponding to the difference calculated by the calculator 25, so as to obtain the average current value according to the output signal current value of the device, and generate the adjustment voltage value according to the difference between the output signal current value of the device and the average current value.

[0050] Exemplarily, the communication interface 24 is a bus interface.

[0051] Exemplarily, the bus interface is a CAN communication circuit or a 485 communication circuit.

[0052] In one embodiment, as Figure 3 shown, the variable AC source 30 includes a signal generator 34, a DC power supply 35, and an inverter bridge circuit 36. The signal generator 34 is connected to the control unit 20 and is used to generate a pulse width modulation signal according to the adjustment voltage value. The DC power supply 35 is used to provide a DC signal. The inverter bridge circuit 36 is respectively connected to the signal generator 34 and the DC power supply 35 and is used to convert the DC signal into an AC signal under the control of the pulse width modulation signal.

[0053] In this embodiment, the variable AC source 30 includes a signal generator 34, a DC power supply 35, and an inverter bridge circuit 36. The signal generator 34 is connected to the control unit 20 and can generate a corresponding pulse width modulation signal according to the adjustment voltage value. The DC power supply 35 can provide a DC signal. The inverter bridge circuit 36 is respectively connected to the signal generator 34 and the DC power supply 35 and can convert the DC signal provided by the DC power supply 35 into an AC signal output under the control of the pulse width modulation signal generated by the signal generator 34. The formation process of the AC signal is controlled by the pulse width adjustment signal, and the pulse width modulation signal is generated according to the adjustment voltage value. Therefore, the AC signal corresponds to the adjustment voltage value. Through the signal generator 34, the DC power supply 35, and the inverter bridge circuit 36, the variable AC source 30 can generate a corresponding AC signal according to the adjustment voltage value.

[0054] Exemplarily, the DC power supply 35 is a battery pack or a DC regulated power supply device.

[0055] Exemplarily, as Figure 3 shown, the inverter bridge circuit 36 includes a first switching tube K1, a second switching tube K2, a third switching tube K3, and a fourth switching tube K4. The control terminals of the first switching tube K1, the second switching tube K2, the third switching tube K3, and the fourth switching tube K4 are respectively connected to the signal generator 34. The first terminal of the first switching tube K1 is connected to the first terminal of the third switching tube K3. The second terminal of the third switching tube K3 is connected to the first terminal of the fourth switching tube K4. The second terminal of the first switching tube K1 is connected to the first terminal of the second switching tube K2. The second terminal of the second switching tube K2 is connected to the second terminal of the fourth switching tube K4.

[0056] Wherein, the first terminal of the first switching tube K1 and the second terminal of the second switching tube K2 are respectively two input terminals of the inverter bridge circuit 36. The second terminal of the first switching tube K1 and the second terminal of the third switching tube K3 are respectively two output terminals of the inverter bridge circuit 36.

[0057] In practical applications, the two input terminals of the inverter bridge circuit 36 are connected to the DC power supply 35 or the rectifier circuit 37. The two output terminals of the inverter bridge circuit 36 are connected to both ends of the first solenoid.

[0058] Exemplarily, the first switching tube K1, the second switching tube K2, the third switching tube K3, and the fourth switching tube K4 can be field effect transistors. At this time, the control terminal is the gate of the field effect transistor, the first terminal is the drain of the field effect transistor, and the second terminal is the source of the field effect transistor.

[0059] In this embodiment, the signal generator 34 generates a PWM (Pulse Width Modulation) signal according to the adjusted voltage value, and adjusts the magnitude of the output voltage by changing the duty cycle of the PWM signal. Among them, when the PWM signal controls the first switching tube K1 and the fourth switching tube K4 to turn on and the second switching tube K2 and the third switching tube K3 to turn off, the positive part of the voltage value in the square wave signal can be output. When the PWM signal controls the second switching tube K2 and the third switching tube K3 to turn on and the first switching tube K1 and the fourth switching tube K4 to turn off, the negative part of the voltage value in the square wave signal can be output.

[0060] Optionally, as Figure 3 shown, the variable AC source 30 further includes a first filter circuit 38, and the first filter circuit 38 is connected in series between the DC power supply 35 and the inverter bridge circuit 36.

[0061] Exemplarily, as Figure 3As shown, the first filter circuit 38 includes a first inductor L1 and a third capacitor C3. The first end of the first inductor L1 is connected to the DC power supply 35, the second end of the first inductor L1 is connected to the first end of the third capacitor C3, and the first end and the second end of the third capacitor C3 are respectively connected to the inverter bridge circuit 36.

[0062] The LC filter circuit composed of the first inductor L1 and the third capacitor C3 can make the DC output more stable.

[0063] Optionally, as Figure 3 shown, the variable AC source 30 further includes a second filter circuit 39, and the second filter circuit 39 is connected to the inverter bridge circuit 36.

[0064] Exemplarily, as Figure 3 shown, the second filter circuit 39 includes a second inductor L2.

[0065] In another embodiment, as Figure 4 shown, the variable AC source 30 includes a signal generator 34, a rectifier circuit 37 and an inverter bridge circuit 36. The signal generator 34 is connected to the control unit 20 and is used to generate a pulse width modulation signal according to the adjusted voltage value. The rectifier circuit 37 is used to provide a DC signal. The inverter bridge circuit 36 is respectively connected to the signal generator 34 and the rectifier circuit 37, and is used to convert the DC signal into an AC signal under the control of the pulse width modulation signal.

[0066] In this embodiment, the rectifier circuit 37 is used to replace the DC power supply 35, and the rectifier circuit 37 is connected to the L / N AC bus. The rectifier circuit 37 can convert the AC signal provided by the L / N AC bus into a DC signal, so as to realize the provision of the DC signal. Moreover, compared with the DC power supply 35, the rectifier circuit 37 can effectively reduce the implementation cost.

[0067] Exemplarily, as Figure 4 shown, the rectifier circuit 37 includes a first diode J1, a second diode J2, a third diode J3 and a fourth diode J4. The negative electrode of the first diode J1 is connected to the negative electrode of the third diode J3, the positive electrode of the first diode J1 is connected to the negative electrode of the second diode J2, the positive electrode of the third diode J3 is connected to the negative electrode of the fourth diode J4, and the positive electrode of the second diode J2 is connected to the positive electrode of the fourth diode J4.

[0068] Wherein, the positive electrodes of the first diode J1 and the third diode J3 are respectively the two input ends of the rectifier circuit 37, and the negative electrode of the first diode J1 and the positive electrode of the second diode J2 are respectively the two output ends of the rectifier circuit 37.

[0069] In practical applications, the two input terminals of the rectifier circuit 37 can be connected to the L / N AC bus, and the two output terminals of the rectifier circuit 37 can be connected to the inverter bridge circuit 36.

[0070] When the voltage value of the AC signal on the L / N AC bus is positive, the first diode J1 and the fourth diode J4 are forward-conducted, and the second diode J2 and the third diode J3 are reverse-blocked. The current direction at the output terminal of the rectifier circuit 37 is from the negative electrode of the first diode J1 to the positive electrode of the fourth diode J4. When the voltage value of the AC signal on the L / N AC bus is negative, the first diode J1 and the fourth diode J4 are reverse-blocked, and the second diode J2 and the third diode J3 are forward-conducted. The current direction at the output terminal of the rectifier circuit 37 is from the negative electrode of the third diode J3 to the positive electrode of the second diode J2. Since the negative electrode of the first diode J1 and the negative electrode of the third diode J3 are the same output terminal of the rectifier circuit 37, and the positive electrode of the fourth diode J4 and the positive electrode of the second diode J2 are the same output terminal of the rectifier circuit 37, the rectifier circuit 37 outputs a DC signal.

[0071] Optionally, as Figure 4 shown, the variable AC source 30 further includes a first filter circuit 38, and the first filter circuit 38 is connected in series between the rectifier circuit 37 and the inverter bridge circuit 36.

[0072] Exemplarily, as Figure 4 shown, the first filter circuit 38 includes a first inductor L1 and a third capacitor C3. The first end of the first inductor L1 and the second end of the third capacitor C3 are respectively connected to the rectifier circuit 37. The second end of the first inductor L1 is connected to the first end of the third capacitor C3. The first end and the second end of the third capacitor C3 are respectively connected to the inverter bridge circuit 36.

[0073] The LC filter circuit composed of the first inductor L1 and the third capacitor C3 can make the DC output more stable.

[0074] Optionally, as Figure 4 shown, the variable AC source 30 further includes a second filter circuit 39, and the second filter circuit 39 is connected to the inverter bridge circuit 36.

[0075] Exemplarily, as Figure 4 shown, the second filter circuit 39 includes a second inductor L2.

[0076] In one embodiment, the device further includes a metal core 43, and the first solenoid 41 and the second solenoid 42 are coaxially wound around the metal core 43.

[0077] By coaxially winding the first solenoid 41 and the second solenoid 42 around the metal core 43, the magnetic field intensity can be enhanced, which is beneficial to generating an induced current.

[0078] In one embodiment, as Figure 5 and Figure 6 shown, the coaxial winding directions of the first solenoid 41 and the second solenoid 42 can be the same.

[0079] When the winding directions of the first solenoid 41 and the second solenoid 42 are the same, the induced current generated has the same direction as the charging current of the L / N AC bus in the main circuit.

[0080] In another embodiment, as Figure 7 and Figure 8 shown, the coaxial winding directions of the first solenoid 41 and the second solenoid 42 are opposite.

[0081] When the winding directions of the first solenoid 41 and the second solenoid 42 are opposite, the induced current generated has the opposite direction to the charging current of the L / N AC bus in the main circuit.

[0082] In one embodiment, as Figure 9 shown, the rectifying unit 50 includes a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4. The negative electrode of the first diode D1 is connected to the negative electrode of the third diode D3, the positive electrode of the first diode D1 is connected to the negative electrode of the second diode D2, the positive electrode of the third diode D3 is connected to the negative electrode of the fourth diode D4, and the positive electrode of the second diode D2 is connected to the positive electrode of the fourth diode D4.

[0083] In practical applications, the input end of the rectifying unit 50 can be connected to the L / N AC bus and the second solenoid. When the voltage value of the AC signal on the L / N AC bus is positive, the first diode D1 and the fourth diode D4 are forward-conductive, and the second diode D2 and the third diode D3 are reverse-blocked. The current direction at the output end of the rectifying circuit 37 is from the negative electrode of the first diode D1 to the positive electrode of the fourth diode D4. When the voltage value of the AC signal on the L / N AC bus is negative, the first diode D1 and the fourth diode D4 are reverse-blocked, and the second diode D2 and the third diode D3 are forward-conductive. The current direction at the output end of the rectifying unit 50 is from the negative electrode of the third diode D3 to the positive electrode of the second diode D2. Since the negative electrode of the first diode D1 and the negative electrode of the third diode D3 are the same output end of the rectifying unit 50, and the positive electrode of the fourth diode D4 and the positive electrode of the second diode D2 are the same output end of the rectifying unit 50, the rectifying unit 50 outputs a DC signal.

[0084] Optionally, as Figure 9 shown, the rectifying unit 50 may further include a first capacitor C1. Both ends of the first capacitor C1 are respectively connected to the positive electrode of the fourth diode D4 and the negative electrode of the third diode D3, and both ends of the first capacitor C1 are the output ends of the rectifying unit 50.

[0085] In another embodiment, as Figure 10 shown, the rectification unit 50 includes a first switching tube S1, a second switching tube S2, a third switching tube S3, a fourth switching tube S4, and the control terminals of the first switching tube S1, the second switching tube S2, the third switching tube S3, and the fourth switching tube S4 are respectively connected to, the first end of the first switching tube S1 is connected to the first end of the third switching tube S3, the second end of the third switching tube S3 is connected to the first end of the fourth switching tube S4, the second end of the first switching tube S1 is connected to the first end of the second switching tube S2, and the second end of the second switching tube S2 is connected to the second end of the fourth switching tube S4.

[0086] In this embodiment, when the rectification unit 50 is connected to an AC input, the DSP chip samples the current value at the output end of the rectification unit 50. When the voltage value of the AC signal on the L / N AC bus is positive, the DSP chip sends a PWM pulse signal to each switching tube, and the second switching tube S2 and the third switching tube S3 are turned on according to the PWM pulse signal, and the first switching tube S1 and the fourth switching tube S4 are kept off at a low level according to the PWM pulse signal. At this time, the current direction at the output end of the rectification unit 50 is from the first end of the third switching tube S3 to the second end of the second switching tube S2. When the voltage value of the AC signal on the L / N AC bus is negative, the DSP chip sends a PWM pulse signal to each switching tube, and the second switching tube S2 and the third switching tube S3 are kept non-conductive at a low level according to the PWM pulse signal, and the first switching tube S1 and the fourth switching tube S4 are turned on according to the PWM pulse signal. At this time, the current direction at the output end of the rectification unit 50 is from the first end of the first switching tube S1 to the second end of the fourth switching tube S4. Since the first end of the first switching tube S1 and the first end of the third switching tube S3 are the same output end of the rectification unit 50, and the second end of the second switching tube S2 and the second end of the fourth switching tube S4 are the same output end of the rectification unit 50, the rectification unit 50 outputs a DC signal.

[0087] Optionally, as Figure 10 shown, the rectification unit 50 may further include a second capacitor C2. The two ends of the second capacitor C2 are respectively connected to the first end of the third switching tube S3 and the second end of the fourth switching tube S4, and the two ends of the second capacitor C2 are the output ends of the rectification unit 50.

[0088] In one of the embodiments, the DSP chip uses a chip of the TMS320F28XX series from Texas Instruments.

[0089] In one embodiment, as Figure 11As shown in the figure, a battery parallel management system is provided. The system includes a plurality of parallel management devices 100. The control units 20 of the plurality of parallel management devices 100 are connected through a communication bus 300. The rectification units of the plurality of parallel management devices 100 are connected to their corresponding battery clusters 200.

[0090] In this embodiment, each device in the battery parallel management system can be corresponding to each of the parallel-connected battery clusters one by one. The current sampler in the device is used to collect the current of the corresponding battery cluster. The control unit in the device is connected to the current sampler, and the control units of each device are connected through a communication bus. Therefore, the currents collected by the current samplers in each device can be centralized. The average current value of the parallel-connected battery clusters can be calculated according to the current values collected by the current samplers in each device. The control unit of each device generates an adjustment voltage value according to the difference between the current value collected by the current sampler in the device and the average current value, and transmits the adjustment voltage value to the connected variable AC source, so as to control the variable AC source to generate a corresponding AC signal according to the adjustment voltage value. The first solenoid is connected to the variable AC source and can receive this AC signal to generate a changing magnetic field. The second solenoid and the first solenoid are coaxially wound and can generate an induced current signal in the changing magnetic field. The rectification unit is connected to the second solenoid and can convert this induced current signal into a DC signal for output. The output DC signal is converted from the induced current signal, the induced current signal is generated in the magnetic field generated by the AC signal, and the AC signal is generated according to the difference between the current value of the battery cluster and the average current value. Therefore, when this DC signal is output to the battery cluster, the current value of the battery cluster can be adjusted to the average current value, so that the current values of each battery cluster are the same average current value, making the currents of each battery cluster reach equilibrium, effectively avoiding charge and discharge between each battery cluster, thereby prolonging the service life of the battery and improving the usability of the entire battery system.

[0091] In practical applications, the devices 100 and the battery clusters 200 are corresponding one by one. The communication interfaces 24 of the control units 20 of the plurality of devices 100 are connected through a communication bus 300 for data exchange. The current sampler 10 of each device 100 is connected to the corresponding battery cluster 200 for collecting the current value of the battery cluster 200. The rectification unit 50 of the device 100 is connected to the battery cluster 200.

[0092] In this embodiment, the current sampler 10 in each device 100 collects the current value of the corresponding battery cluster 200, and transmits the collected current value to the control unit 20 in one device 100 through the communication bus 300. The control unit 20 in this device calculates the average current value from the current values collected by each device 100, and feeds back the average current value to the control unit 20 in other devices 100 through the communication bus 300. The control unit 20 in each device 100 generates an adjustment voltage value based on the difference between the sampled current value it collects and the average current value. The variable AC source 30 in each device 100 generates a corresponding AC signal according to the adjustment voltage value. The first solenoid 41 in each device 100 is connected to the AC signal to generate a changing magnetic field. The second solenoid 42 in each device 100 generates an induced current signal in the changing magnetic field. The rectification unit in each device 100 converts the induced current signal into a DC signal and outputs it to the battery cluster, so as to adjust the current on each battery cluster 200 to be equal.

[0093] The following description is only an exemplary description made under a specific circumstance to show the adjustment process of the battery parallel management system, and should not be construed as a limitation on the scope of the invention patent.

[0094] In one embodiment, the winding directions of the first solenoid 41 and the second solenoid 42 are the same: N parallel management devices 100 start to charge N battery clusters. Let the internal resistances of each cluster of batteries be R1, R2... RN respectively. Assume that R1 < R2 <... < RN. Therefore, I1 > I2 >... > IN, that is, due to the internal resistance, the charging currents of the N clusters of batteries are not exactly equal. Set the average current as IAVE. Assume that at this time the average current satisfies I1 > I2 > IAVE >... > IN. The control units 3... control unit N all send control signals to the variable AC source to increase the output voltage of the variable AC source, enhance the intensity of the alternating magnetic field generated by the first solenoid 41, and then increase the current induced in the second solenoid 42, so that the charging current of the charging circuits corresponding to the control units 3... control unit N rises until it is equal to the average current IAVE. Therefore, I1 > I2 > IAVE =... = IN. At the same time, the control units 1 and 2 send control signals to the variable AC source to reduce the output voltage of the variable AC source, weaken the intensity of the alternating magnetic field generated by the first solenoid 41, and then reduce the induced current of the second solenoid 42, so that the charging current of the charging circuits corresponding to the control units 1 and 2 decreases until it is equal to the average current IAVE, and finally makes I1 = I2 =... = IN. The process of discharging the battery cluster is the same as the above process.

[0095] In another embodiment, the winding directions of the first solenoid 41 and the second solenoid 42 are opposite: N parallel management devices 100 start to charge N battery clusters. Let the internal resistances of each cluster of batteries be R1, R2... RN respectively. Assume that R1 < R2 <... < RN. Therefore, I1 > I2 >... > IN, that is, due to the internal resistance, the charging currents of the N clusters of batteries are not exactly equal. The average current is set as IAVE. Assume that at this time the average current satisfies I1 > I2 > IAVE >... > IN. Control unit 3... control unit N all send control signals to the variable AC source to reduce the output voltage of the variable AC source and weaken the intensity of the alternating magnetic field generated by the first solenoid 41, thereby reducing the current induced in the second solenoid 42, so that the charging currents of the charging circuits corresponding to control unit 3... control unit N rise until they are equal to the average current IAVE. Therefore, I1 > I2 > IAVE =... = IN. At the same time, control unit 1 and control unit 2 send control signals to the variable AC source to increase the output voltage of the AC source and enhance the intensity of the alternating magnetic field generated by the first solenoid 41, thereby increasing the induced current of the second solenoid 42, so that the charging currents of the charging circuits corresponding to control unit 1 and control unit 2 decrease until they are equal to the average current IAVE, and finally make I1 = I2 =... = IN. The process of discharging the battery clusters is the same as the above process.

[0096] In one embodiment, as Figure 12 shown, a battery parallel management method is provided, and the method includes:

[0097] Step S901, respectively collect the current values of each branch where each battery cluster in multiple parallel battery clusters is located.

[0098] Step S902, calculate the average current according to the current values of the branches where multiple parallel battery clusters are located.

[0099] Step S903, according to the difference between the current value of each branch where each parallel battery cluster is located and the average current, pass a DC signal into each branch where each battery cluster is located, so that the current value of each branch where each battery cluster is located is equal to the average current.

[0100] In this embodiment, by respectively collecting the current values of each branch where each battery cluster in multiple parallel battery clusters is located, the average current can be calculated according to the current values of the branches where multiple parallel battery clusters are located. Furthermore, according to the difference between the current value of each branch where each parallel battery cluster is located and the average current, a DC signal is passed into each branch where each battery cluster is located, so that the current value of each branch where each battery cluster is located is equal to the average current, and the currents of each battery cluster reach equilibrium, which can effectively avoid charge and discharge between each battery cluster, thereby prolonging the service life of the battery and improving the usability of the entire battery system.

[0101] In the description of this specification, the descriptions referring to terms such as "some embodiments", "other embodiments", "ideal embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0102] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as within the scope described in this specification.

[0103] The above-described embodiments merely represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A battery parallel management device, characterized in that, the device includes a current sampler (10), a control unit (20), a variable AC source (30), a first solenoid (41), a second solenoid (42) and a rectification unit (50); the input end (11) of the current sampler (10) is connected to the output end of the device, the output end (12) of the current sampler (10) is connected to the input end (21) of the control unit (20), the output end (22) of the control unit (20) is connected to the control end (33) of the variable AC source (30), the output end (32) of the variable AC source (30) is connected to the first solenoid (41), the first solenoid (41) and the second solenoid (42) are coaxially wound, the second solenoid (42) is connected to the input end (51) of the rectification unit (50), and the output end (52) of the rectification unit (50) is the output end of the device; wherein, the current sampler (10) is used to collect the output signal current value of the device; the control unit (20) is used to obtain the current average value according to the output signal current value of the device, and generate an adjustment voltage value according to the difference between the output signal current value of the device and the current average value; the variable AC source (30) is used to generate an AC signal according to the adjustment voltage value; the first solenoid (41) is used to access the AC signal and generate a changing magnetic field; the second solenoid (42) is used to generate an induced current signal in the changing magnetic field; the rectification unit (50) is used to convert the induced current signal into a DC signal and output it.

2. The device according to claim 1, characterized in that, the control unit (20) includes a communication interface (24), a calculator (25), a static memory (26) and a data selector (27), the communication interface (24) and the output end (12) of the current sampler (10) are respectively connected to the input end of the calculator (25), the output end of the calculator (25) is connected to the control end of the data selector (27), the static memory (26) is connected to the input end of the data selector (27), and the output end of the data selector (27) is connected to the input end of the variable AC source (30); wherein, the communication interface (24) is used to receive the output signal current value of other devices; the calculator (25) is used to calculate the current average value of the output signal current value of other devices and the output signal current value of the device, and the difference between the output signal current value of the device and the current average value; the static memory (26) is used to store the corresponding table of the difference and the adjustment voltage value; the data selector (27) is used to generate a corresponding adjustment voltage value according to the difference calculated by the calculator (25) based on the corresponding table.

3. The device according to claim 1, characterized in that, The control unit (20) includes a communication interface (24), a calculator (25), a static memory (26), and a data selector (27). The communication interface (24) and the output terminal (12) of the current sampler (10) are respectively connected to the input terminal of the calculator (25). The output terminal of the calculator (25) is connected to the control terminal of the data selector (27). The static memory (26) is connected to the input terminal of the data selector (27). The output terminal of the data selector (27) is connected to the input terminal of the variable AC source (30); wherein, The communication interface (24) is configured to send the output signal current value of the device and receive the average current value obtained based on the output signal current value of the device; The calculator (25) is configured to calculate the difference between the output signal current value of the device and the average current value; The static memory (26) is configured to store a correspondence table between the difference value and the adjusted voltage value; The data selector (27) is configured to generate a corresponding adjusted voltage value based on the correspondence table according to the difference value calculated by the calculator (25).

4. The device according to any one of claims 1 to 3, wherein, the variable AC source (30) includes: a signal generator (34), connected to the control unit (20), configured to generate a pulse width modulation signal according to the adjusted voltage value; a DC power supply (35), configured to provide a DC signal; an inverter bridge circuit (36), respectively connected to the signal generator (34) and the DC power supply (35), configured to convert the DC signal into an AC signal under the control of the pulse width modulation signal.

5. The device according to any one of claims 1 to 3, wherein, the variable AC source (30) includes: a signal generator (34), connected to the control unit (20), configured to generate a pulse width modulation signal according to the adjusted voltage value; a rectifier circuit (37), configured to provide a DC signal; an inverter bridge circuit (36), respectively connected to the signal generator (34) and the rectifier circuit (37), configured to convert the DC signal into an AC signal under the control of the pulse width modulation signal.

6. The device according to any one of claims 1 to 3, wherein, the device further includes: a metal core (43), on which the first solenoid (41) and the second solenoid (42) are coaxially wound.

7. The device according to any one of claims 1 to 3, wherein, the coaxial winding directions of the first solenoid (41) and the second solenoid (42) can be the same or opposite.

8. The device according to any one of claims 1 to 3, wherein, The rectifying unit (50) includes a first switching transistor S1, a second switching transistor S2, a third switching transistor S3, a fourth switching transistor S4, a second capacitor C2, and a DSP chip. The control terminals of the first switching transistor S1, the second switching transistor S2, the third switching transistor S3, and the fourth switching transistor S4 are respectively connected to the DSP chip. The first ends of the first switching transistor S1 and the third switching transistor S3 are respectively connected to the first end of the second capacitor C2. The second end of the third switching transistor S3 is connected to the first end of the fourth switching transistor S4. The second end of the first switching transistor S1 is connected to the first end of the second switching transistor S2. The second ends of the second switching transistor S2 and the fourth switching transistor S4 are respectively connected to the second end of the second capacitor C2. Both ends of the second capacitor C2 are respectively connected to the DSP chip.

9. A battery parallel management system characterized in that the battery parallel management system includes a plurality of devices (100) as described in any one of claims 1 to 8, and the control units (20) of the plurality of devices (100) are connected through a communication bus (300).

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