Control circuit and control system applied to electrochemical energy storage device

Abstract

The invention relates to the technical field of circuit control, and discloses a control circuit and a control system applied to an electrochemical energy storage device, the control circuit comprises a signal acquisition sub-circuit, a decision sub-circuit and a gating sub-circuit, the signal acquisition sub-circuit respectively acquires real-time current values and real-time voltage values of two battery cells in the charge and discharge process, and the decision sub-circuit acquires the real-time current values and the real-time voltage values of the two battery cells in the charge and discharge process; the decision-making sub-circuit is electrically connected with the signal acquisition sub-circuit and generates two decision-making control signals according to the two real-time current values and the two real-time voltage values, the decision-making control signals are PWM waveforms, and the gating sub-circuit is electrically connected with each battery cell and the decision-making sub-circuit and responds to each decision-making control signal. And the electric energy in the battery cell corresponding to the relatively large real-time voltage value is transferred to the battery cell corresponding to the relatively small real-time voltage value, so that the condition of unbalanced charging and discharging of each battery cell in the electrochemical energy storage device is avoided, and the reliability and the safety of the charging and discharging process of the battery cells are improved.

Description

Technical Field

[0001] The present application relates to the field of circuit control technology and provides a control circuit and a control system applied to an electrochemical energy storage device. Background Art

[0002] At present, the commonly used electrochemical energy storage devices are to directly connect multiple battery cells in series and then discharge them to the external load to supply power to the load. For example, the energy storage backup power of the traditional communication room is to use multiple lead-acid batteries connected in series, and after each lead-acid battery is fully charged, it supplies power to the external load.

[0003] However, due to the inevitable process differences between the battery cells, a battery cell may not be fully charged during charging of the electrochemical energy storage device. Similarly, a battery cell may not be fully discharged during the discharge process, resulting in the energy not being fully utilized. In addition, since the battery cells are connected in series, once a battery cell is damaged during use, the entire electrochemical energy storage device will stop working and will not be able to store energy for backup. Summary of the invention

[0004] The embodiments of the present application provide a control circuit and a control system applied to an electrochemical energy storage device, so as to improve the balance and reliability of the charging and discharging process of each battery cell in the electrochemical energy storage device.

[0005] The specific technical solutions provided by this application are as follows:

[0006] In a first aspect, an embodiment of the present application provides a control circuit for an electrochemical energy storage device, the control circuit comprising: a signal acquisition subcircuit, a decision subcircuit, and a gating subcircuit;

[0007] The signal acquisition subcircuit is electrically connected to two battery cells connected in series, and is configured to respectively acquire real-time current values ​​and real-time voltage values ​​of the two battery cells during the charging and discharging process, wherein the electrochemical energy storage device includes at least two battery cells connected in series;

[0008] The decision subcircuit is electrically connected to the signal acquisition subcircuit, and is configured to generate two decision control signals according to the two real-time current values ​​and the two real-time voltage values, wherein the decision control signals are PWM waveforms;

[0009] The gating subcircuit is electrically connected to each battery cell and the decision subcircuit, and is configured to transfer the electric energy in the battery cell corresponding to the larger real-time voltage value to the battery cell corresponding to the smaller real-time voltage value in response to each decision control signal.

[0010] Optionally, the signal acquisition subcircuit includes: two current sensors, the current sensors and the battery cells are connected in series one by one;

[0011] The current sensor is configured to collect the real-time current value of the battery cell during the charging and discharging process.

[0012] Optionally, the signal acquisition subcircuit includes: two voltage sensors, the voltage sensors are connected in parallel with the battery cells in a one-to-one correspondence;

[0013] The voltage sensor is configured to collect the real-time voltage value of the battery cell during the charging and discharging process.

[0014] Optionally, the decision subcircuit includes two parallel decision channels, each decision channel includes: a preselection control unit, a channel selection unit and a decision control unit;

[0015] The preselection control unit is electrically connected to the current sensor and is configured to generate a preselection control signal according to two real-time current values ​​and a preset reference current value;

[0016] The channel selection unit is electrically connected to the voltage sensor and is configured to generate a channel selection signal according to the real-time voltage value corresponding to each battery cell;

[0017] The preselection control unit and the channel selection unit are both electrically connected to the decision control unit, and the decision control unit is configured to generate a decision control signal according to the preselection control signal and the channel selection signal.

[0018] Optionally, the preselection control unit includes: a subtractor, a proportional integrator, an integral limiter, a triangle wave generator and an operational amplifier;

[0019] A first terminal of the subtractor is electrically connected to a current sensor, a second terminal of the subtractor is electrically connected to a reference current input terminal, and the subtractor is configured to compare the received real-time current value with the reference current value to generate a current difference value;

[0020] The proportional integrator is electrically connected to the subtractor and is configured to perform voltage conversion on the current difference to generate a voltage difference;

[0021] The integral limiter is electrically connected to the proportional integrator and is configured to limit the amplitude of the voltage difference to a preset value range;

[0022] The operational amplifier is electrically connected to the integral limiter and the triangle wave generator, and is configured to generate a preselected control signal in a PWM wave format according to a voltage difference within a preset value range and a triangle wave signal generated by the triangle wave generator.

[0023] Optionally, the channel selection unit comprises: a comparator, wherein the phases of two comparators corresponding to two adjacent decision channels are opposite;

[0024] The positive input terminal of the comparator is electrically connected to one of the two voltage sensors;

[0025] The negative input terminal of the comparator is electrically connected to the other voltage sensor of the two voltage sensors;

[0026] The comparator is configured to generate a channel selection signal according to a real-time voltage value received at the positive input terminal and a real-time voltage value received at the negative input terminal.

[0027] Optionally, the decision control unit includes: an AND gate;

[0028] A first end of the AND gate is electrically connected to an output end of the comparator, a second end of the AND gate is electrically connected to an output end of the operational amplifier, and an output end of the AND gate is electrically connected to a gating subcircuit;

[0029] The AND gate is configured to generate a decision control signal according to a preselection control signal and a channel selection signal.

[0030] Optionally, the gating subcircuit includes: an energy storage element, two drivers and two MOS tubes, wherein each battery cell and a MOS tube form a series circuit, each MOS tube is also electrically connected to the driver, and the two series circuits share the circuit where the energy storage element is located;

[0031] If the real-time voltage value of the battery cell connected in series with the MOS tube is large, the driver is configured to amplify the decision control signal and generate a valid decision control signal, and the MOS tube is configured to be turned on in response to the valid decision control signal and store part of the power of the battery cell in the energy storage element;

[0032] If the real-time voltage value of the battery cell connected in series with the MOS tube is small, the driver is configured to amplify the decision control signal and generate an invalid decision control signal, and the MOS tube is configured to control the body diode to conduct in response to the invalid decision control signal, and provide the electricity in the energy storage element to the battery cell connected in series through the body diode.

[0033] Optionally, the gating subcircuit further includes: two switch tubes, each switch tube being connected in series with a battery cell;

[0034] The switch tube is configured to be cut off in response to a power warning signal to disconnect the series connection between the two battery cells, wherein the power warning signal is generated when the power of the battery cell exceeds a preset power range.

[0035] In a second aspect, an embodiment of the present application further provides a control system for an electrochemical energy storage device, comprising: an electrochemical energy storage device and at least one control circuit;

[0036] Any two adjacent battery cells in the electrochemical energy storage device are connected to a control circuit accordingly;

[0037] The electrochemical energy storage device is configured to transfer electrical energy under the control of a control circuit until the electrical energy between the battery cells is balanced.

[0038] The beneficial effects of this application are as follows:

[0039] In summary, in an embodiment of the present application, a control circuit and a control system for an electrochemical energy storage device are provided, wherein the control circuit comprises: a signal acquisition subcircuit, a decision subcircuit and a gating subcircuit, wherein the signal acquisition subcircuit is electrically connected to two battery cells connected in series, respectively, and is configured to respectively collect the real-time current value and the real-time voltage value of the two battery cells during the charging and discharging process, wherein the electrochemical energy storage device comprises at least two battery cells connected in series, the decision subcircuit is electrically connected to the signal acquisition subcircuit, and is configured to generate two decision control signals according to the two real-time current values ​​and the two real-time voltage values, wherein the decision control signal is a PWM waveform, the gating subcircuit is electrically connected to each battery cell and the decision subcircuit, and is configured to transfer the electric energy in the battery cell corresponding to the larger real-time voltage value to the battery cell corresponding to the smaller real-time voltage value in response to each decision control signal, and the above-mentioned control circuit effectively avoids the situation where the charging and discharging of each battery cell in the electrochemical energy storage device is unbalanced, and improves the reliability and safety of the charging and discharging process of the battery cell.

[0040] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0042] Figure 1 This is a connection diagram of a control circuit applied to an electrochemical energy storage device in an embodiment of the present application;

[0043] Figure 2 This is a circuit connection diagram of the first control circuit applied to an electrochemical energy storage device in the embodiment of the present application;

[0044] Figure 3 This is a schematic diagram of the connections inside the first decision-making subcircuit in the embodiment of the present application;

[0045] Figure 4This is a schematic diagram of the internal connections of the second decision-making sub-circuit in the embodiment of the present application;

[0046] Figure 5 This is a circuit diagram of a second control circuit applied to an electrochemical energy storage device in an embodiment of the present application;

[0047] Figure 6 This is a connection diagram of the first control system applied to an electrochemical energy storage device in an embodiment of the present application;

[0048] Figure 7 This is a connection diagram of a second control system applied to an electrochemical energy storage device in an embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the technical solution of the present application, rather than all of the embodiments. Based on the embodiments recorded in the application documents, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the technical solution of the present application.

[0050] The terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented using sequences other than those illustrated or described herein.

[0051] The preferred implementation modes of the present application are described in detail below with reference to the accompanying drawings.

[0052] See also Figure 1 As shown, in an embodiment of the present application, a control circuit applied to an electrochemical energy storage device specifically includes: a signal acquisition subcircuit 10, a decision subcircuit 20 and a gating subcircuit 30.

[0053] The signal acquisition subcircuit 10 is electrically connected to two battery cells connected in series, and is configured to respectively acquire real-time current values ​​and real-time voltage values ​​of the two battery cells during the charging and discharging process.

[0054] The electrochemical energy storage device in the embodiment of the present application includes at least two battery cells connected in series, and the above-mentioned multiple battery cells are connected in series in sequence. During the charging process, an external charger charges each battery cell connected in series. During the discharge process, each battery cell that has been charged supplies power to the outside. In the embodiment of the present application, in order to avoid the situation where the power of each battery cell is uneven during the charging process, a control circuit is set for the two battery cells. In the following embodiments, the control circuit is introduced by taking two battery cells as an example.

[0055] During the implementation process, a signal acquisition subcircuit 10 is set to monitor the battery cells in real time. On the basis of the two battery cells being connected in series, the signal acquisition subcircuit 10 is also electrically connected to the two battery cells. During the charging and discharging processes, the signal acquisition subcircuit 10 is used to collect the real-time current value and the real-time voltage value of the above two battery cells.

[0056] To collect the real-time current value of the battery cell, refer to Figure 2 As shown, the signal acquisition subcircuit 10 comprises: two current sensors, and the current sensors are connected in series with the battery cells one by one.

[0057] It should be noted that the above-mentioned current sensor can be a sensor for collecting current, such as an ammeter. In order to collect the real-time current value of each battery cell, the signal acquisition subcircuit 10 includes two current sensors, and each current sensor is connected in series with a battery cell in a one-to-one correspondence.

[0058] The current sensor is configured to collect the real-time current value of the battery cell during the charging and discharging process.

[0059] During the charging and discharging process of the battery cell, the current sensor collects the real-time current value of the battery cell in real time. The above real-time current value is the current value of the series circuit formed by the current sensor and the battery cell. In this way, two real-time current values ​​will be obtained after measuring two battery cells.

[0060] To collect the real-time voltage value of the battery cell, refer to Figure 2 As shown, the signal acquisition subcircuit 10 comprises: two voltage sensors, and the voltage sensors are connected in parallel with the battery cells in a one-to-one correspondence.

[0061] It should be noted that the above-mentioned voltage sensor can be a sensor for collecting voltage, such as a voltmeter. In order to collect the real-time voltage value of each battery cell, the signal acquisition subcircuit 10 includes two voltage sensors, each voltage sensor is connected in parallel with a battery cell in a one-to-one correspondence, that is, one end of the voltage sensor is connected to the positive electrode of the battery cell, and the other end of the voltage sensor is connected to the negative electrode of the battery cell.

[0062] The voltage sensor is configured to collect the real-time voltage value of the battery cell during the charging and discharging process.

[0063] During the charging and discharging process of the battery cell, the voltage sensor collects the real-time voltage value of the battery cell in real time. The above real-time voltage value is the voltage value obtained by the voltage sensor measuring the voltage at both ends of the battery cell. In this way, two real-time voltage values ​​will be obtained after measuring the above two battery cells.

[0064] The decision subcircuit 20 is electrically connected to the signal acquisition subcircuit 10 , and is configured to generate two decision control signals according to two real-time current values ​​and two real-time voltage values, wherein the decision control signals are PWM waveforms.

[0065] After collecting two real-time current values ​​and two real-time voltage values, the two real-time current values ​​and two real-time voltage values ​​will be sent to the decision subcircuit 20, and the decision subcircuit 20 generates two decision control signals according to the two real-time current values ​​and two real-time voltage values. It should be added that the above decision control signals are PWM waveforms, which are used to control the intermittent execution of the charging process and the discharging process. In addition, the above two decision control signals are mutually inverted signals, and the selection subcircuit 30 controls one of the two battery cells to perform a normal charging or discharging process under the decision control signal, and at the same time, the other battery cell suspends the charging or discharging process under the decision control signal.

[0066] See also Figure 3 and Figure 4 As shown, the decision subcircuit 20 includes two parallel decision channels, each of which includes: a pre-selection control unit 201 , a channel selection unit 202 and a decision control unit 203 .

[0067] The two parallel decision channels in the decision subcircuit 20 correspond to the battery cells one by one, that is, one battery cell is electrically connected to one decision channel. At the same time, in one embodiment, in order to unify the reference standard, the two parallel decision channels are respectively connected to different reference current input terminals. For example, decision channel 1 is connected to reference current input terminal 1, and decision channel 2 is connected to reference current input terminal 2. In this way, the real-time current value 1 is compared with the reference current value 1 of the reference current input terminal 1, and the real-time current value 2 is compared with the reference current value 2 of the reference current input terminal 2. In another embodiment, the two parallel decision channels are respectively connected to the same reference current input terminal, that is, the real-time current value corresponding to each decision channel is compared with the same reference current value.

[0068] The preselection control unit 201 is electrically connected to the current sensor and is configured to generate a preselection control signal according to two real-time current values ​​and a preset reference current value.

[0069] During implementation, the preselection control unit 201 is electrically connected to the current sensor. After receiving the real-time current value collected by the current sensor, the preselection control unit 201 generates a preselection control signal based on the comparison between the real-time current value and the reference current value.

[0070] For details, see Figure 5 As shown, the preselection control unit 201 includes: a subtractor, a proportional integrator, an integral limiter, a triangle wave generator and an operational amplifier.

[0071] A first terminal of the subtractor is electrically connected to a current sensor, and a second terminal of the subtractor is electrically connected to a reference current input terminal. The subtractor is configured to compare the received real-time current value with the reference current value to generate a current difference.

[0072] See also Figure 5 As shown, a current sensor is electrically connected to the first end of the subtractor, and the collected real-time current value is input into the subtractor. The reference current input end inputs the current of the reference current value into the subtractor through the second end. In this way, the subtractor compares the real-time current value and the reference current value. When the real-time current value and the reference current value are equal, the generated current difference is zero. When the real-time current value and the reference current value are not equal, the generated current difference represents the current value that needs to be adjusted during the charging or discharging process of the battery cell.

[0073] It should be noted that the reference current value refers to the current value required by the battery cell during charging or discharging. The reference current value is usually determined based on the empirical current value of the battery cell of the same type when the battery cell has a balanced charge during charging or discharging.

[0074] The proportional integrator is electrically connected to the subtractor and is configured to perform voltage conversion on the current difference to generate a voltage difference.

[0075] After generating the current difference, the subtractor sends the current difference to the proportional integrator, which converts the current difference into a voltage by using formula (1) to generate a voltage difference.

[0076] U[k]=K p *Err[k]+K i *Err[k]+K d (Err[k]+Err[k-1]) formula (1)

[0077] In the above formula (1), K p , K i and K dAll are proportional parameters inherent in the proportional integrator. Err[k] is the current difference calculated by the subtractor based on the real-time current value of this time. Err[k-1] is the current difference calculated by the subtractor based on the real-time current value collected by the current sensor last time. U[k] is the voltage difference obtained after calculation.

[0078] The integral limiter is electrically connected to the proportional integrator and is configured to limit the amplitude of the voltage difference within a preset value range.

[0079] In order to facilitate the subsequent operation of the operational amplifier, during the implementation process, the integral limiter is electrically connected to the proportional integrator. After receiving the voltage difference sent by the proportional integrator, the integral limiter performs amplitude detection on the voltage difference and changes the amplitude of the voltage difference when the amplitude of the voltage difference exceeds the preset numerical range. For example, when the amplitude of the voltage difference exceeds the maximum value of the preset numerical range, the amplitude of the voltage difference is changed to the maximum value of the preset numerical range; when the amplitude of the voltage difference is lower than the minimum value of the preset numerical range, the amplitude of the voltage difference is changed to the minimum value of the preset numerical range, thereby limiting the amplitude of the voltage difference within the preset numerical range.

[0080] The operational amplifier is electrically connected to the integral limiter and the triangle wave generator, and is configured to generate a preselected control signal in a PWM wave format according to a voltage difference within a preset value range and a triangle wave signal generated by the triangle wave generator.

[0081] During the implementation, the triangle wave signal generated by the triangle wave generator is input into the operational amplifier via the negative input terminal of the operational amplifier, and the voltage difference of the preset numerical range output by the above-mentioned integral limiter is input into the operational amplifier via the positive input terminal, and the operational amplifier generates a preselected control signal according to the above-mentioned voltage difference and the triangle wave signal. It should be noted that the format of the above-mentioned preselected control signal is a PWM wave format. When the real-time current values ​​corresponding to the two decision channels are equal, the preselected control signals generated by the two preselected control units 201 included in the two decision channels are also the same, and the corresponding PWM wave formats are also the same.

[0082] On the other hand, the channel selection unit 202 is electrically connected to the voltage sensor and is configured to generate a channel selection signal according to the real-time voltage value corresponding to each battery cell.

[0083] After the two voltage sensors respectively collect the real-time voltage values ​​of the two battery cells, the voltage sensors send the collected real-time voltage values ​​to the channel selection unit 202. The channel selection unit 202 generates a channel selection signal based on the real-time voltage values. The channel selection signal can be used to control whether the battery cells are normally charged or discharged.

[0084] The channel selection unit 202 includes: a comparator, wherein the phases of two comparators corresponding to two adjacent decision channels are opposite.

[0085] The non-inverting input terminal of the comparator is electrically connected to one of the two voltage sensors.

[0086] The negative input terminal of the comparator is electrically connected to the other voltage sensor of the two voltage sensors.

[0087] The comparator is configured to generate a channel selection signal according to a real-time voltage value received at the positive input terminal and a real-time voltage value received at the negative input terminal.

[0088] During the implementation process, the positive input terminal of the comparator receives a real-time voltage value collected by a voltage sensor, and the negative input terminal of the comparator receives a real-time voltage value collected by another voltage sensor. In this way, the comparator can compare the size between the above two real-time voltage values ​​and generate a channel selection signal based on the comparison result.

[0089] In an embodiment of the present application, the phases of the two comparators corresponding to the two adjacent decision channels are opposite. For example, the battery cell 1 and the battery cell 2 are connected to the control circuit 1 accordingly. In the decision channel 1 of the control circuit 1, the positive input terminal of the comparator 1 is connected to the voltage sensor corresponding to the battery cell 1, and the negative input terminal of the comparator 1 in the decision channel 1 is connected to the voltage sensor corresponding to the battery cell 2; in the decision channel 2 of the control circuit 1, the positive input terminal of the comparator 2 is connected to the voltage sensor corresponding to the battery cell 2, and the negative input terminal of the comparator 2 in the decision channel 2 is connected to the voltage sensor corresponding to the battery cell 1.

[0090] During implementation, when the real-time voltage values ​​corresponding to the two battery cells are not equal, the two comparators corresponding to the two decision channels will output two signals of 1 and 0 respectively. Still using the above example for explanation, when the output of comparator 1 in decision channel 1 is 1, the output of comparator 2 in decision channel 2 is 0; when the output of comparator 1 in decision channel 1 is 0, the output of comparator 2 in decision channel 2 is 1. In this way, the channel selection signals generated by the two comparators corresponding to the two decision channels are 1 and 0 respectively.

[0091] The pre-selection control unit 201 and the channel selection unit 202 are both electrically connected to the decision control unit 203 . The decision control unit 203 is configured to generate a decision control signal according to the pre-selection control signal and the channel selection signal.

[0092] During implementation, after the preselection control unit 201 generates a preselection control signal according to the real-time current value, and the channel selection unit 202 generates a channel selection signal according to the real-time voltage value, the decision control unit 203 further generates a decision control signal according to the preselection control signal and the channel selection signal.

[0093] See also Figure 5 As shown, the decision control unit 203 includes: an AND gate.

[0094] A first terminal of the AND gate is electrically connected to the output terminal of the comparator, a second terminal of the AND gate is electrically connected to the output terminal of the operational amplifier, and an output terminal of the AND gate is electrically connected to the gating subcircuit 30 .

[0095] The AND gate is configured to generate a decision control signal according to the preselect control signal and the channel selection signal.

[0096] During the implementation process, the channel selection signal generated by the comparator according to the real-time voltage value is input to the first end of the AND gate, and the pre-selected control signal generated by the operational amplifier is input to the second end of the AND gate. The AND gate generates a decision control signal after performing an AND operation on the input pre-selected control signal and the channel selection signal.

[0097] Obviously, for two battery cells connected to the same control circuit, when the real-time voltage values ​​corresponding to the two battery cells are not equal, the two comparators corresponding to the two decision channels will output two channel selection signals of 1 and 0 respectively. On this basis, the AND gate in the decision control unit 203 generates two decision control signals according to the pre-selected control signal and the channel selection signal. One decision control signal is 0*pre-selected control signal, that is, 0, and the other decision control signal is 1*pre-selected control signal, that is, the pre-selected control signal.

[0098] The gating subcircuit 30 is electrically connected to each battery cell and the decision subcircuit 20, and is configured to transfer the electric energy in the battery cell corresponding to the larger real-time voltage value to the battery cell corresponding to the smaller real-time voltage value in response to each decision control signal.

[0099] During the implementation process, after generating the decision control signal, the decision control unit 203 will further send the decision control signal to the selection subcircuit 30, so that each battery cell can transfer electric energy under the control of the decision control signal, that is, during the discharge process, especially when a battery cell is monitored to be close to the discharge threshold, the electric energy in the battery cell corresponding to the larger real-time voltage value is transferred to the battery cell to avoid over-discharge of the battery cell; during the charging process, especially when a battery cell is monitored to be close to the charging threshold, the real-time voltage value corresponding to the battery cell will be larger. In this case, the electric energy in the battery cell corresponding to the larger real-time voltage value is transferred to the battery cell corresponding to the smaller real-time voltage value, so as to avoid overcharging of the battery cell.

[0100] See also Figure 2 As shown, the gating subcircuit 30 includes: an energy storage element L1, two drivers and two MOS tubes, wherein each battery cell and a MOS tube form a series circuit, each MOS tube is also electrically connected to the driver, and the two series circuits share the circuit where the energy storage element L1 is located.

[0101] In the embodiment of the present application, a gating subcircuit 30 corresponds to two battery cells and a decision subcircuit 20, and a gating subcircuit 30 includes an energy storage element L1, two drivers and two MOS tubes. In the gating subcircuit 30, each battery cell and a MOS tube form a series circuit, and the above-mentioned MOS tube is used to control the on and off of the series circuit where the battery cell is located. The two decision control signals generated by the decision subcircuit 20 are sent to each MOS tube respectively. In order to ensure that the decision control signal effectively controls the on and off of the MOS tube, each MOS tube is also electrically connected to the driver respectively. In this way, the above-mentioned decision control signal is sent to the control end of the MOS tube after being driven and amplified by the driver. It should be noted that the polarity of the above-mentioned MOS tube can be N-type or P-type, which needs to be determined according to the actual connection of the circuit. In addition, the above-mentioned energy storage element L1 can be an inductor, and the two series circuits share the circuit where the energy storage element L1 is located.

[0102] During implementation, if the real-time voltage values ​​of the two battery cells corresponding to the gated subcircuit 30 are equal, the charging and discharging process of the battery cells can be maintained. When the real-time voltage values ​​of the two battery cells are not equal, the charging and discharging process of the battery cells is controlled.

[0103] If the real-time voltage value of the battery cell connected in series with the MOS tube is large, the driver is configured to amplify the decision control signal and generate a valid decision control signal, and the MOS tube is configured to be turned on in response to the valid decision control signal and store part of the power of the battery cell in the energy storage element L1.

[0104] During the implementation process, when the real-time voltage value of the battery cell connected in series with the MOS tube in the two battery cells corresponding to the gating subcircuit 30 is larger, the decision subcircuit 20 generates a decision control signal according to the real-time voltage value, where the decision control signal is 1*preselected control signal, and the driver amplifies the above decision control signal and generates an effective decision control signal, which is sent to the control end of the MOS tube, so that the MOS tube is turned on under the effective decision control signal. In this way, the series circuit of the battery cell and the MOS tube also includes an energy storage element L1, and the battery cell charges the energy storage element L1, and part of the power of the battery cell will be stored in the energy storage element L1, that is, the energy storage element L1 shares part of the power storage capacity of the battery cell. The amount of the above partial power should be flexibly set according to the actual circuit.

[0105] If the real-time voltage value of the battery cell connected in series with the MOS tube is small, the driver is configured to amplify the decision control signal and generate an invalid decision control signal, and the MOS tube is configured to control the body diode to conduct in response to the invalid decision control signal, and provide the electricity in the energy storage element L1 to the battery cell connected in series through the body diode.

[0106] Correspondingly, when the real-time voltage value of one of the two battery cells corresponding to the selection sub-circuit 30 and connected in series with the MOS tube is larger, the real-time voltage value of the other battery cell in the two battery cells and connected in series with the MOS tube will be smaller. The decision sub-circuit 20 generates a decision control signal according to the smaller real-time voltage value. The decision control signal here is a 0*pre-selected control signal. The driver amplifies the above decision control signal and generates an invalid decision control signal. The invalid decision control signal is sent to the control end of the MOS tube, so that the MOS tube is cut off when the effective decision control signal is turned on, and the body diode in the MOS tube is turned on. In this way, the part of the electricity stored in the energy storage element L1 will be provided to the battery cells connected in series through the body diode, that is, the part of the electricity in the energy storage element L1 is compensated to the battery cell with the smaller real-time voltage value, so that the electric energy in the battery cell corresponding to the larger real-time voltage value can be transferred to the battery cell corresponding to the smaller real-time voltage value.

[0107] In addition, considering that the battery cells in the electrochemical energy storage device are connected in series, when one of the battery cells is damaged, the entire electrochemical energy storage device cannot work properly. Figure 2 As shown, the gating subcircuit 30 further includes: two switch tubes, each of which is connected in series with a battery cell.

[0108] The switch tube is configured to be cut off in response to a power warning signal to disconnect the series connection between the two battery cells, wherein the power warning signal is generated when the power of the battery cell exceeds a preset power range.

[0109] In the embodiment of the present application, the switch tube is connected in series with the battery cell one by one. During the charging and discharging process, if the power of the battery cell exceeds the preset power range, a power warning signal will be generated. The above preset power range is determined based on the empirical value of the same type of battery cells during the charging and discharging process. In this way, the switch tube is cut off after receiving the above power warning signal, that is, the series connection between the battery cell and other battery cells is disconnected, so that other battery cells can be unaffected by the battery cell and continue the normal charging and discharging process. Figure 2 As shown, if the power of the battery cell U1 exceeds the preset power range, the switch tube Q1 and the switch tube Q2 are disconnected when receiving the power warning signal, that is, the series connection between the battery cell U1 and other battery cells is disconnected, and correspondingly, the switch tube Q7 and the switch tube Q8 are turned on when receiving the power warning signal, so that other battery cells will not be affected by the battery cell U1.

[0110] Based on the same inventive concept, refer to Figure 6 and Figure 7 As shown, in an embodiment of the present application, a control system for an electrochemical energy storage device is provided, including: an electrochemical energy storage device 01 and at least one control circuit 02.

[0111] Any two adjacent battery cells in the electrochemical energy storage device 01 are connected to a control circuit 02 accordingly.

[0112] The electrochemical energy storage device 01 is configured to transfer electric energy under the control of the control circuit 02 until the electric energy between the battery cells is balanced.

[0113] In the embodiment of the present application, the number of battery cells included in the electrochemical energy storage device 01 is usually multiple. In order to realize the charge and discharge control of each battery cell, any two adjacent battery cells are connected to a control circuit. For example, battery cell 1 and battery cell 2 are connected to the control circuit 021, battery cell 2 and battery cell 3 are connected to the control circuit 022, battery cell 3 and battery cell 4 are connected to the control circuit 023, and so on.

[0114] During implementation, any two adjacent battery cells can transfer electric energy under the control of a control circuit 02 to achieve electric energy balance between the two battery cells, and then electric energy balance can be achieved between the battery cells in the electrochemical energy storage device 01 under the control of each control circuit 02.

[0115] In summary, in an embodiment of the present application, a control circuit and a control system for an electrochemical energy storage device are provided, wherein the control circuit comprises: a signal acquisition subcircuit, a decision subcircuit and a gating subcircuit, wherein the signal acquisition subcircuit is electrically connected to two battery cells connected in series, respectively, and is configured to respectively collect the real-time current value and the real-time voltage value of the two battery cells during the charging and discharging process, wherein the electrochemical energy storage device comprises at least two battery cells connected in series, the decision subcircuit is electrically connected to the signal acquisition subcircuit, and is configured to generate two decision control signals according to the two real-time current values ​​and the two real-time voltage values, wherein the decision control signal is a PWM waveform, the gating subcircuit is electrically connected to each battery cell and the decision subcircuit, and is configured to transfer the electric energy in the battery cell corresponding to the larger real-time voltage value to the battery cell corresponding to the smaller real-time voltage value in response to each decision control signal, and the above-mentioned control circuit effectively avoids the situation where the charging and discharging of each battery cell in the electrochemical energy storage device is unbalanced, and improves the reliability and safety of the charging and discharging process of the battery cell.

[0116] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, methods or computer program product methods. Therefore, the present application can adopt the form of complete hardware embodiment, complete software embodiment or the embodiment in combination with software and hardware. Moreover, the present application can adopt the form of the computer program product method implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0117] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (methods), and computer program product methods according to the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0118] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0119] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0120] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A control circuit for an electrochemical energy storage device, characterized in that: The control circuit comprises: a signal acquisition subcircuit, a decision subcircuit and a gating subcircuit; The signal acquisition subcircuit is electrically connected to two battery cells connected in series, respectively, and is configured to respectively acquire real-time current values ​​and real-time voltage values ​​of the two battery cells during the charging and discharging process, wherein the electrochemical energy storage device includes at least two battery cells connected in series; The decision subcircuit is electrically connected to the signal acquisition subcircuit, and is configured to generate two decision control signals according to the two real-time current values ​​and the two real-time voltage values, wherein the decision control signals are PWM waveforms; The gating subcircuit is electrically connected to each battery cell and the decision subcircuit, and is configured to transfer the electrical energy in the battery cell corresponding to the larger real-time voltage value to the battery cell corresponding to the smaller real-time voltage value in response to each decision control signal.

2. The control circuit according to claim 1, characterized in that: The signal acquisition subcircuit comprises: two current sensors, the current sensors being connected in series with the battery cells in a one-to-one correspondence; The current sensor is configured to collect the real-time current value of the battery cell during the charging and discharging process.

3. The control circuit according to claim 2, characterized in that: The signal acquisition subcircuit comprises: two voltage sensors, the voltage sensors being connected in parallel with the battery cells in a one-to-one correspondence; The voltage sensor is configured to collect the real-time voltage value of the battery cell during the charging and discharging process.

4. The control circuit according to claim 3, characterized in that: The decision subcircuit comprises two parallel decision channels, each of which comprises: a preselection control unit, a channel selection unit and a decision control unit; The preselection control unit is electrically connected to the current sensor and is configured to generate a preselection control signal according to the two real-time current values ​​and a preset reference current value; The channel selection unit is electrically connected to the voltage sensor and is configured to generate a channel selection signal according to the real-time voltage value corresponding to each battery cell; The preselection control unit and the channel selection unit are both electrically connected to the decision control unit, and the decision control unit is configured to generate a decision control signal according to each of the preselection control signals and the channel selection signal.

5. The control circuit according to claim 4, characterized in that: The preselection control unit comprises: a subtractor, a proportional integrator, an integral limiter, a triangular wave generator and an operational amplifier; The first end of the subtractor is electrically connected to one of the current sensors, and the second end of the subtractor is electrically connected to the reference current input terminal, and is configured to compare the received real-time current value with the reference current value to generate a current difference value; The proportional integrator is electrically connected to the subtractor and is configured to perform voltage conversion on the current difference to generate a voltage difference; The integral limiter is electrically connected to the proportional integrator and is configured to limit the amplitude of the voltage difference to a preset value range; The operational amplifier is electrically connected to the integral limiter and the triangular wave generator, and is configured to generate the preselected control signal in a PWM wave format according to the voltage difference in the preset numerical range and the triangular wave signal generated by the triangular wave generator.

6. The control circuit according to claim 4, characterized in that: The channel selection unit comprises: a comparator, wherein the phases of the two comparators corresponding to the two adjacent decision channels are opposite; The positive input terminal of the comparator is electrically connected to one of the two voltage sensors; The negative input terminal of the comparator is electrically connected to the other voltage sensor of the two voltage sensors; The comparator is configured to generate a channel selection signal according to the real-time voltage value received by the positive input terminal and the real-time voltage value received by the negative input terminal.

7. The control circuit according to claim 4, characterized in that: The decision control unit comprises: an AND gate; The first end of the AND gate is electrically connected to the output end of the comparator, the second end of the AND gate is electrically connected to the output end of the operational amplifier, and the output end of the AND gate is electrically connected to the gating subcircuit; The AND gate is configured to generate the decision control signal according to the preselection control signal and the channel selection signal.

8. The control circuit according to claim 1, characterized in that: The gating subcircuit comprises: an energy storage element, two drivers and two MOS tubes, wherein each battery cell and one of the MOS tubes form a series circuit, each of the MOS tubes is also electrically connected to the driver, and the two series circuits share the circuit where the energy storage element is located; If the real-time voltage value of the battery cell connected in series with the MOS tube is larger, the driver is configured to amplify the decision control signal and generate a valid decision control signal, and the MOS tube is configured to be turned on in response to the valid decision control signal and store part of the power of the battery cell in the energy storage element; If the real-time voltage value of the battery cell connected in series with the MOS tube is small, the driver is configured to amplify the decision control signal and generate an invalid decision control signal, and the MOS tube is configured to control the conduction of the body diode in response to the invalid decision control signal, and provide the electricity in the energy storage element to the battery cell connected in series through the body diode.

9. The control circuit according to any one of claims 1 to 8, characterized in that: The gating subcircuit further includes: two switch tubes, each of which is connected in series with a battery cell; The switch tube is configured to be cut off in response to a power warning signal to disconnect the series connection between two battery cells, wherein the power warning signal is generated when the power of the battery cell exceeds a preset power range.

10. A control system for an electrochemical energy storage device, characterized in that: include: The electrochemical energy storage device and at least one of the control circuits; Any two adjacent battery cells in the electrochemical energy storage device are correspondingly connected to one of the control circuits; The electrochemical energy storage device is configured to transfer electric energy under the control of the control circuit until the electric energy between the battery cells is balanced.

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