Range switching circuit and formation and capacity grading system

Abstract

The embodiment of the utility model provides a range switching circuit and a formation and capacity grading system, and belongs to the technical field of electronic circuits. The range switching circuit comprises: a reactor circuit comprising a plurality of reactors; a sampling circuit coupled to the reactor circuit to detect a current flowing through the reactor circuit; the range switching module comprises a switch control circuit and at least one bypass switch module, the bypass switch module is connected with the at least one electric reactor in parallel, a switch control pin of the bypass switch module is connected with the switch control circuit, and the rate of a switch signal output by the switch control circuit is larger than the sampling rate of the sampling circuit; and the current compensation module is connected with the sampling loop of the sampling circuit and is used for performing current compensation under the condition that the current of the sampling loop changes suddenly. According to the embodiment of the invention, the current measurement precision of the battery in the formation and capacity grading process is improved.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and in particular to a range switching circuit and a capacity conversion system. Background Technology

[0002] Formation and capacity testing is a crucial step in battery production. Through a formation and capacity testing system, batteries can be charged with both low and high currents, and undergo charge-discharge tests to determine their product grade standards. In this process, current measurement plays a vital role.

[0003] Different current measurement ranges need to be switched for different batteries. Although the relevant technologies can switch the range online, switching the range can easily lead to unstable current operation and current interruption during the switching process, affecting continuous current measurement and making accurate measurement impossible. Utility Model Content

[0004] The main objective of this application is to propose a range switching circuit that can improve the accuracy of current measurement of the battery during the formation and capacity testing process.

[0005] To achieve the above objectives, a first aspect of the embodiments of this application provides a range switching circuit, including:

[0006] A reactor circuit, comprising multiple reactors;

[0007] A sampling circuit, coupled to the reactor circuit, is used to detect the current flowing through the reactor circuit.

[0008] A range switching module includes a switch control circuit and at least one bypass switch module. The bypass switch module is connected in parallel with at least one reactor. The switch control pin of the bypass switch module is connected to the switch control circuit. The rate of the switch signal output by the switch control circuit is greater than the sampling rate of the sampling circuit.

[0009] A current compensation module is connected to the sampling circuit of the sampling circuit and is used to perform current compensation in the event of a sudden change in the current of the sampling circuit.

[0010] In some embodiments, the plurality of reactors includes a plurality of first reactors and a plurality of second reactors, wherein the first reactors and the second reactors are connected to form a series circuit, and the two ends of the series circuit are respectively coupled to the positive and negative terminals of the battery under test.

[0011] In some embodiments, the plurality of first reactors include a first inductor, a second inductor, and a third inductor, which are connected in series in sequence; the plurality of second reactors include a first resistor, a second resistor, and a third resistor, which are connected in series in sequence; and the third inductor is connected in series with the first resistor.

[0012] In some embodiments, the second inductor is connected in parallel with the first bypass switch module, the third inductor is connected in parallel with the second bypass switch module, the first resistor is connected in parallel with the third bypass switch module, and the second resistor is connected in parallel with the fourth bypass switch module.

[0013] In some embodiments, the switch control pins of both the first bypass switch module and the third bypass switch module are connected to the first switch signal output pin of the switch control circuit, and the switch control pins of both the second bypass switch module and the fourth bypass switch module are connected to the second switch signal output pin of the switch control circuit.

[0014] In some embodiments, the sampling circuit further includes a sampling loop switching switch, which includes a common terminal, a first terminal, a second terminal, a third terminal, and a switching component. One end of the switching component is connected to the common terminal, and the other end is controlled to be connected to the first terminal, the second terminal, and the third terminal. The first terminal is coupled to the connection between the third inductor and the first resistor, the second terminal is coupled to the connection between the first resistor and the second resistor, and the third terminal is coupled to the connection between the second resistor and the third resistor. A sampling loop is formed between the connection between the third resistor and the battery under test and the common terminal.

[0015] In some embodiments, when the first bypass switch module, the second bypass switch module, the third bypass switch module, and the fourth bypass switch module are in the off state, the range switching circuit is in the first range, and the switching component is connected to the common terminal and the first terminal;

[0016] When the first bypass switch module and the third bypass switch module are in the closed state, and the second bypass switch module and the fourth bypass switch module are in the closed state, the range switching circuit is in the second range, and the switching component is connected to the common terminal and the second terminal;

[0017] When the first bypass switch module, the second bypass switch module, the third bypass switch module, and the fourth bypass switch module are in the closed state, the range switching circuit is in the third range, and the switching component is connected to the common terminal and the third terminal.

[0018] In some embodiments, the bypass switch module includes a first MOSFET and a second MOSFET, which are connected in reverse series, and the control pins of the first MOSFET and the second MOSFET are connected.

[0019] In some embodiments, the current compensation module includes a compensation circuit, the input terminal of which is connected to the current output terminal of the sampling circuit, and the output terminal of which is used to output the compensated sampling current. The compensation circuit is used to compensate the sampling current through at least one of a capacitor, an inductor, and a current control chip.

[0020] Secondly, embodiments of this application provide a batching and capacity-regulating system, including the range switching circuit described in the first aspect.

[0021] The range switching circuit and formation / capacity testing system proposed in this application have the following beneficial effects: The range switching circuit is equipped with multiple reactors forming a reactor circuit, and a bypass switch module connected in parallel with the reactor is provided. By controlling the switching state of the bypass switch module through the switch control circuit, the resistance of the reactor circuit can be changed, thereby changing the measurement range of the range switching circuit. Furthermore, the rate of the switching signal output by the switch control circuit is set to be greater than the sampling rate of the sampling circuit, thereby avoiding data interruption of the sampling current when switching ranges. On the other hand, the current compensation module compensates for current fluctuations during range switching, suppressing sudden changes and fluctuations in the sampling current data. Therefore, the above-mentioned range switching circuit can overcome the problems of current interruption and sudden changes that occur during range switching, thereby improving the accuracy of current measurement of the battery during the formation / capacity testing process.

[0022] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the description and the accompanying drawings. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the range switching circuit provided in the embodiments of this application;

[0024] Figure 2 This is a circuit diagram of the range switching circuit provided in the embodiments of this application;

[0025] Figure 3 This is a schematic diagram of the formulation and compatibilization system provided in the embodiments of this application. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0027] It should be noted that although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. The terms "first," "second," etc., in the specification, claims, and the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0028] 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 belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0029] Formation and capacity testing is a crucial step in battery production. Through a formation and capacity testing system, batteries can be charged with both low and high currents, and undergo charge-discharge tests to determine their product grade standards. In this process, current measurement plays a vital role.

[0030] Different current measurement ranges need to be switched for different batteries. Although the relevant technologies can switch the range online, switching the range can easily lead to unstable current operation and current interruption during the switching process, affecting continuous current measurement and making accurate measurement impossible.

[0031] To address the aforementioned issues, this embodiment provides a range switching circuit and a capacity formation system. The range switching circuit comprises multiple reactors forming a reactor circuit, with a bypass switch module connected in parallel to each reactor. By controlling the switching state of the bypass switch module through a switch control circuit, the resistance of the reactor circuit can be altered, thereby changing the measurement range of the range switching circuit. Furthermore, the rate of the switching signal output by the switch control circuit is set to be greater than the sampling rate of the sampling circuit, thus preventing data interruption of the sampling current during range switching. On the other hand, a current compensation module compensates for current fluctuations during range switching, suppressing sudden changes and fluctuations in the sampling current data. Therefore, the aforementioned range switching circuit overcomes problems such as current interruption and sudden changes during range switching, thereby improving the accuracy of current measurement of the battery during capacity formation.

[0032] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the range switching circuit provided in the embodiments of this application.

[0033] In some embodiments, the range switching circuit includes a reactor circuit 100, a sampling circuit 200, a range switching module 300, and a current compensation module 400. The reactor circuit 100 includes multiple reactors. The sampling circuit 200 is coupled to the reactor circuit 100 to detect the current flowing through the reactor circuit 100. The range switching module 300 includes a switch control circuit 350 and at least one bypass switch module 360. The bypass switch module 360 ​​is connected in parallel with at least one reactor. The switch control pin of the bypass switch module 360 ​​is connected to the switch control circuit 350. The rate of the switch signal output by the switch control circuit 350 is greater than the sampling rate of the sampling circuit 200, thereby avoiding data interruption of the sampling current when switching ranges, maintaining the stability of the sampling current, and further maintaining stable data transmission.

[0034] In current measurement, the thermal effect of the shunt resistor and the influence of parasitic thermocouples may lead to increased errors and drift. In this embodiment, the current compensation module 400 is connected to the sampling circuit 200 to perform current compensation in the event of a sudden current change in the sampling circuit, suppressing sudden changes and fluctuations in the sampled current data. This allows it to adapt to different measurement needs and improve the dynamic range and accuracy of the measurement.

[0035] Please refer to Figure 2 , Figure 2 This is a circuit diagram of the range switching circuit provided in the embodiments of this application.

[0036] In some embodiments, the plurality of reactors include a plurality of first reactors 110 and a plurality of second reactors 120. The first reactors 110 and the second reactors 120 are connected to form a series circuit, and the two ends of the series circuit are respectively coupled to the positive and negative terminals of the battery under test.

[0037] Specifically, the plurality of first reactors 110 include a first inductor L1, a second inductor L2, and a third inductor L3, which are connected in series. The second inductor L2 is connected to both the first inductor L1 and the third inductor L3. The plurality of second reactors 120 include a first resistor R1, a second resistor R2, and a third resistor R3, which are connected in series. That is, the second resistor R2 is connected to both the first resistor R1 and the third resistor R3. The third inductor L3 is connected in series with the first resistor R1.

[0038] In some embodiments, the second inductor L2 is connected in parallel with the first bypass switch module 310 to connect or disconnect the second inductor L2 through the first bypass switch module 310; the third inductor L3 is connected in parallel with the second bypass switch module 320 to connect or disconnect the third inductor L3 through the second bypass switch module 320; the first resistor R1 is connected in parallel with the third bypass switch module 330 to connect or disconnect the first resistor R1 through the third bypass switch module 330; and the second resistor R2 is connected in parallel with the fourth bypass switch module 340 to connect or disconnect the second resistor R2 through the fourth bypass switch module 340.

[0039] It is understood that the first bypass switch module 310, the second bypass switch module 320, the third bypass switch module 330 and the fourth bypass switch module 340 in the embodiments of this application are respectively used to connect or disconnect the second inductor L2, the third inductor L3, the first resistor R1 and the second resistor R2, thereby changing the resistance value in the circuit and further changing the range of the range switching circuit. This will be described in detail below, and will not be repeated here.

[0040] In some embodiments, the switch control pins of both the first bypass switch module 310 and the third bypass switch module 330 are connected to the first switch signal output pin of the switch control circuit 350, that is, the signal output by the first switch signal output pin can simultaneously change the switch state of the first bypass switch module 310 and the third bypass switch module 330; the switch control pins of both the second bypass switch module 320 and the fourth bypass switch module 340 are connected to the second switch signal output pin of the switch control circuit 350, that is, the signal output by the second switch signal output pin can simultaneously change the switch state of the second bypass switch module 320 and the fourth bypass switch module 340.

[0041] For example, when the first switch signal output pin outputs a high-level signal, the first bypass switch module 310 and the third bypass switch module 330 are in a closed state; when the first switch signal output pin outputs a low-level signal, the first bypass switch module 310 and the third bypass switch module 330 are in an open state, and so on. Similarly, when the second switch signal output pin outputs a high-level signal, the second bypass switch module 320 and the fourth bypass switch module 340 are in a closed state; when the second switch signal output pin outputs a low-level signal, the second bypass switch module 320 and the fourth bypass switch module 340 are in an open state, and so on. The embodiments of this application do not impose specific limitations.

[0042] In some embodiments, the sampling circuit 200 further includes a sampling loop switching switch, which includes a common terminal I0, a first terminal I1, a second terminal I2, a third terminal I3, and a switching component. One end of the switching component is connected to the common terminal I0, and the other end is controlled to be connected to the first terminal I1, the second terminal I2, and the third terminal I3. In this embodiment, the common terminal I0 can be connected to different terminals by receiving signals from the controller or by manual switching.

[0043] In this embodiment, the first terminal I1 is coupled to the connection between the third inductor L3 and the first resistor R1, the second terminal I2 is coupled to the connection between the first resistor R1 and the second resistor R2, and the third terminal I3 is coupled to the connection between the second resistor R2 and the third resistor R3. A sampling circuit is formed between the connection between the third resistor R3 and the battery under test and the common terminal I0 to measure the current flowing through the battery under test, thereby achieving accurate current measurement.

[0044] In some embodiments, when the first bypass switch module 310, the second bypass switch module 320, the third bypass switch module 330, and the fourth bypass switch module 340 are in the off state, the first inductor L1, the second inductor L2, and the third inductor L3 in the circuit are all in the on state, and the first resistor R1, the second resistor R2, and the third resistor R3 in the circuit are all in the on state. The range switching circuit is in the first range, and the switching component is connected to the common terminal I0 and the first terminal I1 to achieve accurate measurement of the current within the first range.

[0045] When the first bypass switch module 310 and the third bypass switch module 330 are in the closed state, and the second bypass switch module 320 and the fourth bypass switch module 340 are in the closed state, the second inductor L2 and the first resistor R1 in the circuit are in the open state, and the first inductor L1, the third inductor L3, the second resistor R2 and the third resistor R3 are in the connected state. The first range switching circuit is in the second range, and the switching component is connected to the common terminal I0 and the second terminal I2 to achieve accurate measurement of the current in the second range.

[0046] When the first bypass switch module 310, the second bypass switch module 320, the third bypass switch module 330, and the fourth bypass switch module 340 are in the closed state, the first inductor L1, the second inductor L2, the third inductor L3, the first resistor R1, the second resistor R2, and the third resistor R3 in the circuit are all in the connected state. The range switching circuit is in the third range, and the switching component is connected to the common terminal I0 and the third terminal I3 to achieve accurate measurement of the current in the third range.

[0047] It should be noted that in the embodiments of this application, the measurement range of the first range, the measurement range of the second range, and the measurement range of the third range increase sequentially. Specifically, the measurement range of the first range is 0 to 300 mA, the measurement range of the second range is 300 mA to 3 A, and the measurement range of the third range is 3 A to 12 A.

[0048] In some embodiments, the bypass switch module 360 ​​includes a first MOSFET and a second MOSFET, which are connected in reverse series and the control pins of the first MOSFET and the second MOSFET are connected together.

[0049] It is understood that the first bypass switch module 310, the second bypass switch module 320, the third bypass switch module 330 and the fourth bypass switch module 340 in the embodiments of this application each include two MOSFETs, and the control pins of the MOSFETs in each bypass switch module are connected.

[0050] Specifically, in the embodiments of this application, the control pins of the two MOSFETs in the first bypass switch module 310 are connected to the first switch signal output pin, the control pins of the two MOSFETs in the second bypass switch module 320 are connected to the second switch signal output pin, the control pins of the two MOSFETs in the third bypass switch module 330 are connected to the first switch signal output pin, and the control pins of the two MOSFETs in the fourth bypass switch module 340 are connected to the second switch signal output pin.

[0051] In some embodiments, the current compensation module 400 includes a compensation circuit. The input terminal of the compensation circuit is connected to the current output terminal of the sampling circuit 200. The output terminal of the compensation circuit is used to output the compensated sampling current. The compensation circuit is used to compensate the sampling current through at least one of a capacitor, an inductor, and a current control chip, thereby suppressing sudden changes and fluctuations in the sampling current data, achieving seamless switching between different ranges, and improving the stability of range switching.

[0052] Please refer to Figure 3 , Figure 3 This is a schematic diagram of the formulation and compatibilization system provided in the embodiments of this application.

[0053] In some embodiments, this application also provides a formation and capacity control system, which includes the range switching circuit as described above. The specific implementation of the formation and capacity control system is basically the same as the specific implementation of the range switching circuit described above, and will not be repeated here.

[0054] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0055] It will be understood by those skilled in the art that Figures 1 to 3 The technical solutions shown herein do not constitute a limitation on the embodiments of this application.

[0056] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0057] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0058] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0059] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0060] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A range switching circuit, characterized by comprising: The application relates to a current sampling circuit for a battery, comprising: a reactor circuit comprising a plurality of reactors; a sampling circuit coupled to the reactor circuit to detect current flowing through the reactor circuit; a range switching module comprising a switch control circuit and at least one bypass switch module, the bypass switch module being connected in parallel with at least one of the reactors, a switch control pin of the bypass switch module being connected to the switch control circuit, a switching signal output by the switch control circuit having a higher frequency than a sampling frequency of the sampling circuit; a current compensation module connected to a sampling loop of the sampling circuit to compensate for current in the sampling loop in the event of a sudden change in current.

2. The range switching circuit of claim 1, wherein, The plurality of reactors comprises a plurality of first reactors and a plurality of second reactors, the first reactors and the second reactors being connected to form a series circuit, two ends of the series circuit being coupled to a positive electrode and a negative electrode of a battery to be tested, respectively.

3. The range switching circuit of claim 2, wherein, The plurality of first reactors comprises a first inductor, a second inductor and a third inductor, the first inductor, the second inductor and the third inductor being connected in series in sequence; the plurality of second reactors comprises a first resistor, a second resistor and a third resistor, the first resistor, the second resistor and the third resistor being connected in series in sequence; the third inductor is connected in series with the first resistor.

4. The range switching circuit of claim 3, wherein, The second inductor is connected in parallel with a first bypass switch module, the third inductor is connected in parallel with a second bypass switch module, the first resistor is connected in parallel with a third bypass switch module, and the second resistor is connected in parallel with a fourth bypass switch module.

5. The range switching circuit of claim 4, wherein, Switch control pins of the first bypass switch module and the third bypass switch module are connected to a first switch signal output pin of the switch control circuit, and switch control pins of the second bypass switch module and the fourth bypass switch module are connected to a second switch signal output pin of the switch control circuit.

6. The range switching circuit of claim 4, wherein, The sampling circuit further comprises a sampling loop switching switch, the sampling loop switching switch comprising a common terminal, a first terminal, a second terminal, a third terminal and a switching component, one end of the switching component being connected to the common terminal, and the other end being controllably connected to the first terminal, the second terminal and the third terminal; the first terminal is coupled to a connection between the third inductor and the first resistor, the second terminal is coupled to a connection between the first resistor and the second resistor, and the third terminal is coupled to a connection between the second resistor and the third resistor; A connection between the third resistor and the battery to be tested and the common terminal form a sampling loop.

7. The range switching circuit of claim 6, wherein, In the case where the first bypass switch module, the second bypass switch module, the third bypass switch module and the fourth bypass switch module are in an open state, the range switching circuit is in a first range, and the switching component connects the common terminal and the first terminal; In the case where the first bypass switch module and the third bypass switch module are in a closed state, and the second bypass switch module and the fourth bypass switch module are in a closed state, the range switching circuit is in a second range, and the switching component connects the common terminal and the second terminal; In a case where the first bypass switch module, the second bypass switch module, the third bypass switch module and the fourth bypass switch module are in a closed state, the range switching circuit is in a third range, and the switching assembly connects the common end and the third end.

8. The range switching circuit of claim 1, wherein, The bypass switch module comprises a first MOS transistor and a second MOS transistor, the first MOS transistor and the second MOS transistor are connected in reverse series, and control pins of the first MOS transistor and the second MOS transistor are connected.

9. The range switching circuit of claim 1, wherein, The current compensation module comprises a compensation circuit, an input end of the compensation circuit is connected with a current output end of the sampling circuit, an output end of the compensation circuit is used for outputting a compensated sampling current, and the compensation circuit is used for compensating the sampling current through at least one of a capacitor, an inductor and a current control chip.

10. A formation and dispensing system, characterized by, The range switching circuit comprises a first bypass switch module, a second bypass switch module, a third bypass switch module and a fourth bypass switch module. The range switching circuit comprises a first bypass switch module, a second bypass switch module, a third bypass switch module and a fourth bypass switch module.

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