CN115172941A - Battery self-heating circuit and control method thereof - Google Patents
Battery self-heating circuit and control method thereof Download PDFInfo
- Publication number
- CN115172941A CN115172941A CN202210928219.2A CN202210928219A CN115172941A CN 115172941 A CN115172941 A CN 115172941A CN 202210928219 A CN202210928219 A CN 202210928219A CN 115172941 A CN115172941 A CN 115172941A
- Authority
- CN
- China
- Prior art keywords
- battery
- transformer
- circuit
- module
- bridge
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000010438 heat treatment Methods 0.000 title claims abstract description 85
- 238000000034 method Methods 0.000 title claims abstract description 33
- 239000003990 capacitor Substances 0.000 claims description 54
- 238000010586 diagram Methods 0.000 description 26
- 230000008569 process Effects 0.000 description 12
- 230000001965 increasing effect Effects 0.000 description 9
- 230000003068 static effect Effects 0.000 description 6
- 230000009471 action Effects 0.000 description 5
- 230000008859 change Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 230000003321 amplification Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000002708 enhancing effect Effects 0.000 description 2
- 230000005669 field effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 1
- 230000005534 acoustic noise Effects 0.000 description 1
- OJIJEKBXJYRIBZ-UHFFFAOYSA-N cadmium nickel Chemical compound [Ni].[Cd] OJIJEKBXJYRIBZ-UHFFFAOYSA-N 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 229910001416 lithium ion Inorganic materials 0.000 description 1
- 229910052987 metal hydride Inorganic materials 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000002985 plastic film Substances 0.000 description 1
- 229920006255 plastic film Polymers 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 230000017105 transposition Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/60—Heating or cooling; Temperature control
- H01M10/61—Types of temperature control
- H01M10/615—Heating or keeping warm
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/60—Heating or cooling; Temperature control
- H01M10/62—Heating or cooling; Temperature control specially adapted for specific applications
- H01M10/625—Vehicles
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/60—Heating or cooling; Temperature control
- H01M10/63—Control systems
- H01M10/633—Control systems characterised by algorithms, flow charts, software details or the like
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/60—Heating or cooling; Temperature control
- H01M10/63—Control systems
- H01M10/637—Control systems characterised by the use of reversible temperature-sensitive devices, e.g. NTC, PTC or bimetal devices; characterised by control of the internal current flowing through the cells, e.g. by switching
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Automation & Control Theory (AREA)
- Secondary Cells (AREA)
Abstract
The embodiment of the application provides a battery self-heating circuit and a control method thereof, in the battery self-heating circuit, alternating voltage is applied to a primary side of a transformer through a driving circuit, so that current is generated on the primary side, and amplified by the transformer, great secondary side current is generated on a secondary side, the secondary side current flows through a battery pack, resistance heat is generated on the internal resistance of the battery to heat the battery, so that the self-heating of the battery is realized, and the heating efficiency of the battery is improved.
Description
Technical Field
The application relates to the technical field of battery heating, in particular to a battery self-heating circuit and a control method thereof.
Background
At present, new energy automobiles are developed vigorously, and power batteries are correspondingly applied in a large quantity. However, due to the inherent characteristics of the power battery, when the battery is in a low temperature state, the driving range of the vehicle is reduced, the charging efficiency is also affected to a certain extent, and in this case, if a large current is used for charging, permanent damage is easily caused to the battery, and the service life and the capacity of the battery are reduced. Therefore, when the battery is used, the power battery is often required to be heated to raise the temperature of the battery cell.
In the related art, a water path is generally heated by a PTC (Positive Temperature Coefficient) heating element, and then the power battery is subjected to heat conduction in a circulation manner through the water path, so that a certain Temperature is applied to the battery. This scheme is through heating the indirect heating battery of water route, and heating efficiency is lower.
Disclosure of Invention
The embodiment of the application aims to provide a battery self-heating circuit and a control method thereof, and aims to improve the heating efficiency of a battery.
In a first aspect, an embodiment of the present application provides a battery self-heating circuit, including a battery pack, a transformer, a driving circuit, and a switch module, where: the battery pack is used for providing a power supply; the primary side of the transformer is connected with the driving circuit, the secondary side of the transformer is connected with the battery pack, and the transformer is used for amplifying the current of the primary side and then outputting the amplified current to the secondary side; the driving circuit is used for applying alternating voltage to the primary side of the transformer to heat the battery pack when the battery pack needs to be heated; the switch module is connected between the driving circuit and the transformer and used for controlling the on-off of a circuit between the driving circuit and the transformer.
In the implementation process, alternating voltage is applied to the primary side of the transformer through the driving circuit, so that current is generated on the primary side, and large secondary side current is generated on the secondary side through the amplification of the transformer, and the secondary side current flows through the battery pack to generate resistance heat on the internal resistance of the battery to heat the battery, so that the self-heating of the battery is realized, and the heating efficiency of the battery is improved.
Further, in some embodiments, the battery pack includes a first battery cell and a second battery cell connected in parallel, the first battery cell includes a first battery module and a second battery module connected in series, and the second battery cell includes a third battery module and a fourth battery module connected in series, wherein one end of the secondary side of the transformer is connected between the first battery module and the second battery module, and the other end is connected between the third battery module and the fourth battery module.
In the implementation process, the two battery units provide a circulation path for heating current, and the heating current can flow back and forth at the middle points of the two battery units, so that the heating of each battery module is realized. Because the heating current flows between the two battery units, the heating current cannot flow out of the battery pack to the high-voltage direct-current bus, and disturbance to the voltage of the high-voltage direct-current bus is avoided.
Further, in some embodiments, a voltage ratio between the first battery module and the second battery module is the same as a voltage ratio between the third battery module and the fourth battery module.
In the implementation process, the situation that the battery is damaged due to the fact that the two battery units are rapidly discharged through the secondary side of the transformer due to static pressure difference is avoided by limiting the voltage ratio between the first battery module and the second battery module to be the same as the voltage ratio between the third battery module and the fourth battery module.
Further, in some embodiments, the first, second, third, and fourth battery modules have the same electrical characteristics, including at least one of: battery capacity, voltage.
In the implementation process, the battery modules are defined to be interchangeable in electrical property, so that the high-frequency heating current is uniformly distributed among the battery modules to ensure the heat generation balance among all parts of the battery pack.
Further, in some embodiments, the battery pack includes a first battery unit and a first capacitor module, the first battery unit includes a first battery module and a second battery module connected in series, the first capacitor module is connected to a positive electrode or a negative electrode of the first battery unit, one end of the secondary side of the transformer is connected between the first battery module and the second battery module, and the other end of the secondary side of the transformer is connected to the first capacitor module.
In the above implementation, another implementation of the battery side is provided.
Further, in some embodiments, the driving circuit includes a three-phase inverter circuit connected to a motor through three ac cables; one end of the primary side of the transformer is connected with the first switch module and then connected to the first phase output end of the three-phase inverter circuit, and the other end of the primary side of the transformer is connected to the second phase output end of the three-phase inverter circuit.
In the implementation process, the three-phase inverter circuit of the multiplexing motor controller is used as a driving circuit, namely, an implementation scheme of a driving side is provided.
Further, in some embodiments, the method further comprises: and the second capacitor module is connected between the primary side of the transformer and the second phase output end of the three-phase inverter circuit, and the second capacitor module is used for forming a resonant circuit with the leakage inductance of the transformer.
In the implementation process, by additionally arranging the second capacitor module, on one hand, the second capacitor module and the leakage inductance of the transformer form a resonance circuit to play a role in increasing the amplitude of the high-frequency resonance current, and on the other hand, the second capacitor module also plays a role in isolating the direct-current voltage and preventing the magnetic core of the transformer from magnetic biasing saturation.
Further, in some embodiments, the drive circuit comprises a full bridge circuit or a half bridge circuit.
In the implementation process, another implementation scheme of the driving side is provided, the flexibility of control can be improved by additionally arranging a full-bridge circuit or a half-bridge circuit, and the driving circuit cannot be influenced after the motor controller is decoupled.
Further, in some embodiments, the transformer includes at least two secondary sides, each secondary side and the battery pack form a battery full-bridge unit, and the battery full-bridge units are combined in series, in parallel or in both series and parallel.
In the implementation process, the design scheme on one side of the transformer is provided, so that the arrangement is more flexible structurally, and the battery heating power can be improved to a certain extent.
In a second aspect, an embodiment of the present application provides a method for controlling a self-heating circuit of a battery according to the first aspect, where the three-phase inverter circuit of the self-heating circuit of the battery includes a first half-bridge, a second half-bridge and a third half-bridge, where the first half-bridge is the first phase output terminal, and the second half-bridge is the second phase output terminal, and the method includes: and when the three-phase inverter circuit is subjected to PWM modulation, the switching-on time periods of the high-low voltage side power switching devices of the first half bridge or the second half bridge are exchanged.
In the implementation process, the switching-on time periods of the high-low voltage side power switching devices connected with one phase output end of the primary side of the transformer are exchanged, so that the alternating voltage applied to the primary side by the driving circuit is obviously increased, and the heating efficiency of the battery is effectively improved.
Additional features and advantages of the disclosure will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the above-described techniques.
In order to make the aforementioned objects, features and advantages of the present application more comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
To more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.
Fig. 1 is a schematic diagram of a battery self-heating circuit according to an embodiment of the present disclosure;
FIG. 2 is a schematic diagram of a circuit of a conventional pure electric vehicle power system in the related art according to an embodiment of the present application;
FIG. 3A is a schematic diagram of an improved battery self-heating circuit provided by an embodiment of the present application;
FIG. 3B is a schematic diagram illustrating the effect of the capacitor Cr on enhancing the high-frequency heating current according to an embodiment of the present invention;
fig. 3C is a schematic diagram of a conventional SVPWM driving and a SVPWM driving after Q1Q2 timing shift according to an embodiment of the present application;
fig. 4A is a schematic diagram of a battery self-heating circuit using a full-bridge circuit to drive a transformer according to an embodiment of the present disclosure;
FIG. 4B is a schematic diagram of a battery self-heating circuit using a half-bridge driving transformer according to an embodiment of the present disclosure;
FIG. 4C, including FIGS. 4C (1) and 4C (2), is a schematic diagram of two battery self-heating circuits provided by an embodiment of the present application, wherein the transformer is driven by a half-bridge circuit, and the interval resonant capacitor and the half-bridge voltage dividing capacitor are multiplexed;
fig. 5A is a schematic diagram of a battery self-heating circuit for replacing a set of batteries connected in series with a set of capacitors connected in series according to an embodiment of the present disclosure;
FIG. 5B, including FIGS. 5B (1) and 5B (2), is a schematic diagram of two battery self-heating circuits provided by embodiments of the present application that replace a set of batteries in series with a single capacitor;
fig. 6A is a schematic diagram of a full-bridge cell of a battery according to an embodiment of the present disclosure;
FIG. 6B is a schematic diagram of a battery self-heating circuit based on a transformer including a plurality of secondary sides according to an embodiment of the present application;
fig. 6C, which includes fig. 6C (1) and fig. 6C (2), is a schematic diagram of two battery self-heating circuits based on multiple transformers according to an embodiment of the present application.
Detailed Description
The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.
As described in the related art, the current battery heating scheme has a problem of low heating efficiency. Accordingly, the present disclosure provides a self-heating circuit for a battery, so as to solve the above-mentioned problems.
Next, embodiments of the present application will be described:
as shown in fig. 1, fig. 1 is a schematic diagram of a battery self-heating circuit provided in an embodiment of the present application, where the battery self-heating circuit includes: a battery pack 11, a transformer 12, a driving circuit 13 and a switch module 14; wherein, the battery pack 11 is used for providing power; the primary side of the transformer 12 is connected with the driving circuit 13, the secondary side of the transformer 12 is connected with the battery pack 11, and the transformer 12 is used for amplifying the current of the primary side and then outputting the amplified current to the secondary side; the driving circuit 13 is configured to apply an alternating voltage to the primary side of the transformer 12 to heat the battery pack 11 when the battery pack 11 needs to be heated; the switch module 14 is connected between the driving circuit 13 and the transformer 12, and the switch module 14 is configured to control on/off of a circuit between the driving circuit 13 and the transformer 12.
The circuit can be applied to electric equipment taking a power battery as a power source, such as an electric automobile, an electric ship and the like. The principle of the circuit is that alternating voltage is applied to the primary side of the transformer through the driving circuit, so that current is generated on the primary side, and large secondary side current is generated on the secondary side through the amplification of the transformer, and the secondary side current flows through the battery pack to generate resistance heat on the internal resistance of the battery to heat the battery, so that the self-heating of the battery is realized, and the heating efficiency of the battery is improved.
Specifically, in the above circuit, the battery pack may be a power battery, such as a lithium ion-based power battery, or a nickel-metal hydride battery. The battery pack can be connected with a high-voltage direct-current bus to provide power for loads on the high-voltage direct-current bus, such as a motor controller. In this embodiment, the battery pack is connected to the secondary side of the transformer, and the battery pack is heated by receiving the amplified secondary side current.
In some embodiments, the battery pack may include a first battery cell and a second battery cell connected in parallel, the first battery cell including a first battery module and a second battery module connected in series, the second battery cell including a third battery module and a fourth battery module connected in series, wherein one end of the secondary side of the transformer is connected between the first battery module and the second battery module, and the other end is connected between the third battery module and the fourth battery module. That is, the first battery module, the second battery module, the third battery module, and the fourth battery module are respectively denoted as U1, U2, U3, and U4, then U1 and U2 constitute one "battery half bridge", and denoted as U1U2, and U3 and U4 constitute another "battery half bridge", and denoted as U3U4, and the secondary side of the transformer is connected between the two "battery half bridges" U1U2 and U3U 4. In this way, the two battery half-bridges provide a flow path for the heating current, which can flow back and forth at the midpoint of the two battery half-bridges, thereby achieving heating of the individual battery modules. Because the heating current flows between the two battery units, the heating current cannot flow out of the battery pack to the high-voltage direct-current bus, and the disturbance of the voltage of the high-voltage direct-current bus is avoided. In addition, any one of U1, U2, U3, and U4 may be a single battery, or may be a battery assembly in which at least two single batteries are connected in series, in parallel, or in series and parallel, and only one pair of positive and negative output terminals is provided, and the type of the battery assembly may be a lithium battery, a lead-acid battery, a nickel-cadmium battery, or the like.
Further, in some embodiments, a voltage ratio between the first battery module and the second battery module is the same as a voltage ratio between the third battery module and the fourth battery module. That is, the voltage ratio U1/U2= U3/U4. Therefore, the situation that the two battery units are rapidly discharged through the secondary side of the transformer due to static pressure difference, and the battery is damaged is avoided.
Still further, in some embodiments, the first battery module, the second battery module, the third battery module, and the fourth battery module have the same electrical characteristics. The electrical characteristics refer to the state of the device in terms of electrical aspects, such as voltage, capacity, current, conductivity, etc., that is, U1, U2, U3 and U4 may be identical in terms of capacity, voltage, etc., i.e., they may be interchangeable in terms of electrical properties. Therefore, the high-frequency heating current is uniformly distributed among the battery modules, and the heating balance among all parts of the battery pack is easily ensured.
Regarding the battery pack side, the following scheme can also be implemented: in some embodiments, the first battery cell or the second battery cell may be replaced by a set of series capacitors. The capacitor may be a film capacitor, which is a capacitor using a plastic film as a dielectric, and generally can bear a high current and has a strong voltage endurance. Following the previous example, the second battery unit is replaced by a series connection of capacitors Cb1 and Cb1, i.e. U1 and U2 form a "battery half-bridge", denoted U1U2, and Cb1 form another "capacitor half-bridge", denoted Cb1Cb2, and the secondary side of the transformer is connected between the two "half-bridges" U1U2, cb1Cb 2. In some other embodiments, the battery pack includes a first battery unit and a first capacitor module, the first battery unit includes a first battery module and a second battery module connected in series, the first capacitor module is connected to a positive electrode or a negative electrode of the first battery unit, one end of the secondary side of the transformer is connected between the first battery module and the second battery module, and the other end of the secondary side of the transformer is connected to the first capacitor module. That is, only a single capacitor may be connected to the positive electrode or the negative electrode of the battery instead of the second battery unit, so that a relatively simple structure may be realized and costs may be reduced.
In the circuit, the transformer is used for amplifying the small current of the primary side into the large current of the secondary side. The main components of the transformer comprise an iron core and a winding, wherein the iron core is a magnetic circuit part of the transformer, and the winding is a circuit part of the transformer.
In some embodiments, the transformer may have a plurality of secondary sides, each secondary side and the battery pack form a battery full-bridge unit, and the plurality of battery full-bridge units are combined in series and parallel. This may lead to a more flexible arrangement in construction, while also increasing the power of the battery heating to some extent.
In other embodiments, there may be at least two sets of transformers, the primary sides of each set of transformers may be connected in series or in parallel, the respective secondary sides of each set of transformers may be connected with the battery pack to form a full-bridge battery unit, and then the full-bridge battery units may be connected in series or in parallel. Also, this may lead to a more flexible arrangement in construction, while also increasing the power of the battery heating to some extent.
In the above circuit, the driving circuit is used to apply an alternating voltage to the primary side of the transformer, that is, the driving circuit is a circuit that can generate an alternating voltage. In some embodiments, the driving circuit includes a three-phase inverter circuit connected to the motor by three ac cables; one end of the primary side of the transformer is connected to the first switch module and then connected to the first phase output end of the three-phase inverter circuit, and the other end of the primary side of the transformer is connected to the second phase output end of the three-phase inverter circuit. In the related art, a motor controller of a power system of a conventional electric vehicle generally includes a three-phase inverter circuit composed of 6 power switching tubes, the three-phase inverter circuit can convert a dc input into a three-phase ac output, and output terminals of the three-phase inverter circuit include an a-phase output terminal, a B-phase output terminal, and a C-phase output terminal. In this embodiment, the three-phase inverter circuit may be multiplexed, where one end of the primary side of the transformer is connected to one phase output terminal of the three-phase inverter bridge of the motor controller, and the other end of the primary side of the transformer is connected to the other phase output terminal of the three-phase inverter bridge of the motor controller, and a current is generated in the primary side of the transformer based on a voltage difference between the two phases. It should be noted that the first phase output end and the second phase output end may be any two of the phases a, B, and C. It should also be noted that, no matter the motor is in a static state or a running state, an alternating voltage difference with the frequency of the power switch action exists between any two phases due to the switching action of the power switch, so that the heating function can be used when the driving motor is static or running.
In other embodiments, the drive circuit may comprise a full bridge circuit or a half bridge circuit. The full-bridge or half-bridge circuit may be a dedicated circuit that is not multiplexed with the three-phase inverter circuit of the motor controller. Through addding full-bridge circuit or half-bridge circuit, can improve the flexibility of control, and after the motor controller decoupling zero, this drive circuit can not receive the influence.
It should be noted that the driving circuit may be powered by a battery pack, or may include a power supply module, and the power supply module supplies power to the driving circuit. Alternatively, the power module may be a 12V lead acid battery. Of course, in other embodiments, the power supply module may be other types of batteries. This is not limited by the present application.
In the above circuit, the switch module is used to control the on/off of the circuit between the driving circuit and the transformer, i.e. the primary side circuit, that is, when the battery is not needed to heat at all, the switch module can cut off the primary side circuit to stop heating completely. Alternatively, the switch module may be a relay, such as an electromagnetic relay, a solid state relay, or the like. A relay is an electric control device that generates a predetermined step change in a controlled amount in an electric output circuit when a change in an input amount (excitation amount) meets a predetermined requirement. When the battery pack needs to be heated, the relay is closed, and the primary side circuit is in a conducting state; when the battery pack does not need to be heated, the relay is disconnected, and the primary side circuit is in a disconnected state. It should be noted that the relay may be connected to a control module formed by a single chip, and the control module may control the on/off of the primary side circuit by controlling the relay. Of course, in other embodiments, the switch module may be other types of electronic devices, and the application is not limited thereto.
In practical applications, the transformer needs to use a higher switching frequency, because the lower switching frequency has many negative effects, including significant acoustic noise, and increases in volume, weight, and cost. However, when the switching frequency of the transformer is increased, the effective value of the heating current is reduced due to the impedance of the leakage inductance of the transformer, thereby affecting the heating efficiency. Based on this, in some embodiments, the above circuit may further include: and the second capacitor module is connected between the primary side of the transformer and the second phase output end of the three-phase inverter circuit, and the second capacitor module is used for forming a resonant circuit with the leakage inductance of the transformer. The second capacitance module is a capacitor, and can form an LC resonance circuit with the leakage inductance of the transformer, the resonance frequency of the resonance circuit can be designed by selecting the capacitance value of the second capacitance module, the impedance of the second capacitance module and the impedance of the leakage inductance of the transformer are mutually offset at the resonance frequency of the resonance circuit, the primary side presents pure resistance, the primary side impedance reaches a minimum value, the corresponding primary side current reaches a maximum value, and the secondary side current also correspondingly reaches a maximum value. Thus, the self-heating efficiency of the battery is improved. In addition, the second capacitor module can play a role in isolating direct-current voltage and preventing magnetic bias saturation of the transformer core besides playing a role in increasing the amplitude of the high-frequency resonance current.
In addition, as for the control method of the circuit, the following two schemes may be adopted to drive the transformer to generate current, where the drive circuit includes a three-phase inverter circuit of the motor controller, and the primary sides of the transformer are respectively connected to the two phases AB of the three-phase inverter circuit:
the first scheme comprises the following steps: under the condition that the motor is static, the AB two-phase bridge arm drives the transformer to work in a full-bridge mode, which can be a common full-bridge driving mode or a phase-shifting conduction driving mode, and simultaneously controls the average value of high-frequency alternating current between the AB two phases of the motor, so that the motor does not output effective torque, and at the moment, the C phase bridge arm switch does not act, or although the C phase bridge arm switch acts, the average torque generated by the high-frequency alternating current of the motor is almost zero; under the condition that the motor runs, the motor is driven by adopting a traditional three-phase inverter PWM (Pulse Width Modulation) method, and at the moment, the voltage difference between the AB two phases has alternating voltage, so that the transformer can be driven to generate current.
The second scheme is a special three-phase PWM modulation method provided in the present application, assuming that power switching devices of the three-phase inverter circuit are Q1, Q2, Q3, Q4, Q5, and Q6, where Q1Q2, Q3Q4, and Q5Q6 are a first half-bridge, a second half-bridge, and a third half-bridge in sequence, and the first half-bridge is an a-phase output end, and the second half-bridge is a B-phase output end, the method includes: and when the three-phase inverter circuit is subjected to PWM modulation, the switching-on periods of the high-low voltage side power switching devices of the first half bridge or the second half bridge are exchanged. When the traditional PWM is adopted, such as Space Vector Pulse Width Modulation (SVPWM), the centers of the opening time periods of the three high-voltage side switching tubes Q1, Q3, Q5 are all aligned at a time, and the centers of the opening time periods of the three low-voltage side switching tubes Q2, Q4, Q6 are aligned at a time that differs by half a PWM period, so that when the rotating speed of the motor is low or even static, the opening duty ratios of the six switching tubes are substantially 50%, and thus the voltage difference between the two phases AB of the motor is small; after the Q1Q2 time sequence is ectopic or the Q3Q4 time sequence is ectopic, the voltage difference between two phases of the motor AB is obviously increased, so that the primary side of the transformer is effectively driven, and the heating efficiency is further improved. It should be noted that the method for timing sequence dislocation of the switching tube on the high and low voltage sides is also applicable to other types of three-phase PWM Modulation modes, such as SPWM (Sine Pulse Width Modulation), DPWM (Digital Pulse Width Modulation), and the like; moreover, this method not only provides an effective driving voltage at low motor speeds, but also provides advantages in the case of high motor speed operation.
To illustrate the solution of the present application in more detail, a specific embodiment is described below:
as shown in fig. 2, fig. 2 is a schematic diagram of a conventional pure electric vehicle power system circuit in the related art, wherein a battery pack 21 is connected to a high-voltage dc bus through a main positive relay Kp22 and a main negative relay Kn23, and a main load on the high-voltage dc bus is a motor controller 24. The motor controller 24 includes a dc bus supporting capacitor Cdc241 and a three-phase inverter circuit composed of 6 power switch tubes Q1, Q2, Q3, Q4, Q5, Q6 (labeled as 242, 243, 244, 245, 246, 247 in sequence in the figure), wherein Q1Q2, Q3Q4, Q5Q6 are combined two by two into three half-bridges, and the power switch tubes may be Semiconductor switch devices such as IGBTs (Insulated Gate Bipolar transistors) or MOSFETs (Metal-Oxide-Semiconductor Field-Effect transistors, metal-Oxide Semiconductor Field-Effect transistors); the three-phase inverter circuit is connected with a driving motor 25 through three alternating current cables, and the driving motor can be a permanent magnet synchronous motor, a direct current brushless motor or a three-phase asynchronous motor.
The schematic circuit diagram of the embodiment of the present application is shown in fig. 3A, and it should be noted that the circuit actually further includes a dc bus support capacitor Cdc (for convenience, not shown in the figure). Compared with the conventional scheme shown in fig. 2, the hardware change points at least include: the battery pack 31 is divided into four parts, i.e., U1, U2, U3 and U4, which are connected in series, and the four parts are interchangeable in electrical property, and U1 and U2 form a U1U2 half-bridge, and U3 and U4 form a U3U4 half-bridge; the secondary side of the transformer Tx32 is connected between the two half bridges U1U2 and U3U4, one end of the primary side is connected to the relay Ka33 and then connected to one phase output terminal (for example, phase a) of the three-phase inverter bridge of the motor controller 34, and the other end is connected to the capacitor Cr35 and then connected to the other phase output terminal (for example, phase B) of the three-phase inverter bridge of the motor controller 34.
The battery self-heating circuit can be divided into a driving side circuit and a battery side circuit, wherein the driving side circuit and the battery side circuit are coupled by a transformer, the driving side circuit is used for applying alternating voltage to a primary side of the transformer, and the battery side circuit bears amplified secondary side current to heat the battery. In the circuit of fig. 3A, the battery pack 31 is on the battery side, and the multiplexed three-phase inverter circuit is on the driving side; in addition, the relay Ka33 is used for completely opening the circuit when the battery does not need to be heated, specifically, when the battery does not need to be heated, only the relays Kp36 and Kn37 are closed to connect the battery pack 31 to the bus for supplying power, and when the battery needs to be heated, the relay Ka33 is also closed except for the relays Kp36 and Kn 37; the capacitor Cr35 is used for preventing bias saturation of the transformer and increasing the amplitude of the high-frequency resonant current, as shown in fig. 3B, fig. 3B is a schematic diagram of the capacitor Cr provided in the embodiment of the present application for enhancing the high-frequency heating current, where a solid line shows a case when the capacitor Cr is present, and a dotted line shows a case when the capacitor Cr is absent, as can be seen from fig. 3B, by adding the capacitor Cr, the heating efficiency can be improved on the basis of reducing the negative effect caused by the leakage inductance of the transformer.
Meanwhile, aiming at the battery self-heating circuit of the embodiment of the application, the following control method is adopted: the SVPWM is adopted to modulate a three-phase inverter circuit, and simultaneously, a high-low voltage side switching tube such as a Q1Q2 switching-on period of one phase output end of a primary side of a transformer is exchanged. This control method is applicable not only to the case where the motor 38 is operating at a low speed but also to the case where the motor 38 is operating at a high speed. As shown in fig. 3C, fig. 3C is a schematic diagram of the conventional SVPWM driving and the SVPWM driving after the Q1Q2 time sequence transposition provided by the embodiment of the present application, wherein the left diagram shows the on-period of each switching tube and the voltage difference between two phases of the motor AB during the conventional SVPWM driving; and after the Q1Q2 time sequence is transposed, the on-period of each switching tube and the voltage difference between two phases of the motor AB are shown in the right graph. As shown in fig. 3C, after the new scheme is adopted, the voltage difference between the two phases of the motor AB is significantly increased, so that the primary side of the transformer is effectively driven, and the battery heating efficiency is effectively improved.
In addition, the present application provides the following variations on the circuit shown in fig. 3A (for convenience, only the changed parts of the circuit are labeled in the schematic diagram of the following variations, and some devices of the circuit are not shown or labeled):
for the drive side, the transformer can be driven with a full-bridge circuit or a half-bridge circuit. As shown in fig. 4A, fig. 4A is a schematic diagram of a battery self-heating circuit using a full-bridge circuit to drive a transformer according to an embodiment of the present application, where the full-bridge circuit 41 is a special circuit that is not multiplexed with a three-phase inverter circuit; alternatively, as shown in fig. 4B, fig. 4B is a schematic diagram of a battery self-heating circuit using a half-bridge circuit driving transformer according to an embodiment of the present application, wherein the half-bridge circuit 42 is a special circuit not multiplexed with a three-phase inverter circuit. It should be noted that, when a half-bridge circuit is used to drive the transformer, the duty-off resonant capacitor Cr may be multiplexed with the half-bridge voltage-dividing capacitor, as shown in fig. 4C, fig. 4C is a schematic diagram of two kinds of battery self-heating circuits provided in the embodiment of the present application, when the half-bridge circuit is used to drive the transformer, and the duty-off resonant capacitor and the half-bridge voltage-dividing capacitor are multiplexed, where the half-bridge circuit 43 in fig. 4C (1) and the half-bridge circuit 44 in fig. 4C (2) are two implementation manners of multiplexing the duty-off resonant capacitor and the half-bridge voltage-dividing capacitor.
For the battery side, a set of series batteries may be replaced with a set of series capacitors, or a single capacitor may be connected to the battery positive or negative. As shown in fig. 5A, fig. 5A is a schematic diagram of a battery self-heating circuit for replacing a set of batteries connected in series with a set of capacitors connected in series according to an embodiment of the present application, where capacitor Cb1 (51) and capacitor Cb2 (52) are capacitors connected in series and replacing batteries; alternatively, as shown in fig. 5B, fig. 5B (1) is a schematic diagram of a battery self-heating circuit provided in this embodiment of the present application, where a group of batteries connected in series is replaced by a single capacitor, and fig. 5B (2) is a schematic diagram of another battery self-heating circuit provided in this embodiment of the present application, where a group of batteries connected in series is replaced by a single capacitor.
For the transformer, the transformer may have a plurality of secondary sides, as shown in fig. 6A, each secondary side may form a battery full-bridge unit with the battery, and the plurality of battery full-bridge units may be combined in series and parallel to obtain the battery self-heating circuit as shown in fig. 6B, or there may be a plurality of sets of transformers, the primary side of each set of transformers may be connected in series or parallel, and their respective secondary sides may form a battery full-bridge unit with the battery pack, and then the battery full-bridge units may be connected in series and parallel at will to obtain the battery self-heating circuit as shown in fig. 6C, where fig. 6C (1) is a battery self-heating circuit based on a plurality of transformers and having their primary sides connected in parallel, and fig. 6C (2) is a battery self-heating circuit based on a plurality of transformers and having their primary sides connected in series.
Through above-mentioned change scheme, can structurally bring more nimble arrangement, also can improve battery heating efficiency to a certain extent.
The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising one of 8230; \8230;" 8230; "does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.
Claims (10)
1. The utility model provides a battery self-heating circuit which characterized in that, includes battery package, transformer, drive circuit and switch module, wherein:
the battery pack is used for providing a power supply;
the primary side of the transformer is connected with the driving circuit, the secondary side of the transformer is connected with the battery pack, and the transformer is used for amplifying the current of the primary side and then outputting the amplified current to the secondary side;
the driving circuit is used for applying alternating voltage to the primary side of the transformer to heat the battery pack when the battery pack needs to be heated;
the switch module is connected between the driving circuit and the transformer and used for controlling the on-off of a circuit between the driving circuit and the transformer.
2. The battery self-heating circuit according to claim 1, wherein the battery pack comprises a first battery cell and a second battery cell connected in parallel, the first battery cell comprises a first battery module and a second battery module connected in series, the second battery cell comprises a third battery module and a fourth battery module connected in series, wherein one end of the secondary side of the transformer is connected between the first battery module and the second battery module, and the other end is connected between the third battery module and the fourth battery module.
3. The battery self-heating circuit according to claim 2, wherein a voltage ratio between the first battery module and the second battery module is the same as a voltage ratio between the third battery module and the fourth battery module.
4. The battery self-heating circuit of claim 2, wherein the first, second, third, and fourth battery modules have the same electrical characteristics, the electrical characteristics comprising at least one of: battery capacity, voltage.
5. The battery self-heating circuit according to claim 1, wherein the battery pack comprises a first battery unit and a first capacitor module, the first battery unit comprises a first battery module and a second battery module which are connected in series, the first capacitor module is connected with a positive electrode or a negative electrode of the first battery unit, one end of the secondary side of the transformer is connected between the first battery module and the second battery module, and the other end of the secondary side of the transformer is connected with the first capacitor module.
6. The battery self-heating circuit according to claim 1, wherein the driving circuit comprises a three-phase inverter circuit connected to a motor through three ac cables; one end of the primary side of the transformer is connected with the first switch module and then connected to the first phase output end of the three-phase inverter circuit, and the other end of the primary side of the transformer is connected to the second phase output end of the three-phase inverter circuit.
7. The battery self-heating circuit of claim 6, further comprising:
and the second capacitor module is connected between the primary side of the transformer and the second phase output end of the three-phase inverter circuit, and the second capacitor module is used for forming a resonant circuit with the leakage inductance of the transformer.
8. The battery self-heating circuit of claim 1, wherein the drive circuit comprises a full bridge circuit or a half bridge circuit.
9. The battery self-heating circuit of claim 1, wherein the transformer comprises at least two secondary sides, each secondary side and the battery pack form a battery full-bridge unit, and the battery full-bridge units are combined in series, parallel or both series and parallel.
10. A control method of a battery self-heating circuit according to any one of claims 6 to 7, the three-phase inverter circuit of the battery self-heating circuit including a first half-bridge, a second half-bridge and a third half-bridge, wherein the first half-bridge is the first phase output terminal, and the second half-bridge is the second phase output terminal, comprising:
and when the three-phase inverter circuit is subjected to PWM modulation, the switching-on time periods of the high-low voltage side power switching devices of the first half bridge or the second half bridge are exchanged.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210928219.2A CN115172941A (en) | 2022-08-03 | 2022-08-03 | Battery self-heating circuit and control method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210928219.2A CN115172941A (en) | 2022-08-03 | 2022-08-03 | Battery self-heating circuit and control method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115172941A true CN115172941A (en) | 2022-10-11 |
Family
ID=83477748
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210928219.2A Pending CN115172941A (en) | 2022-08-03 | 2022-08-03 | Battery self-heating circuit and control method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115172941A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116454475A (en) * | 2023-06-15 | 2023-07-18 | 宁德时代新能源科技股份有限公司 | Battery heating circuit, control method and device thereof, electronic equipment and storage medium |
| WO2024087398A1 (en) * | 2022-10-26 | 2024-05-02 | 广汽埃安新能源汽车股份有限公司 | Transformer-based battery heating circuit, and electric vehicle |
-
2022
- 2022-08-03 CN CN202210928219.2A patent/CN115172941A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024087398A1 (en) * | 2022-10-26 | 2024-05-02 | 广汽埃安新能源汽车股份有限公司 | Transformer-based battery heating circuit, and electric vehicle |
| CN116454475A (en) * | 2023-06-15 | 2023-07-18 | 宁德时代新能源科技股份有限公司 | Battery heating circuit, control method and device thereof, electronic equipment and storage medium |
| CN116454475B (en) * | 2023-06-15 | 2024-02-13 | 宁德时代新能源科技股份有限公司 | Battery heating circuit, control method and device thereof, electronic equipment and storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20240246428A1 (en) | Constant current fast charging of electric vehicles via dc grid using dual inverter drive | |
| CN115172941A (en) | Battery self-heating circuit and control method thereof | |
| US20230097060A1 (en) | Energy conversion device and vehicle | |
| Korn et al. | Low output frequency operation of the modular multi-level converter | |
| CN212587580U (en) | Battery energy processing device and vehicle | |
| Ewanchuk et al. | A five-/nine-level twelve-switch neutral-point-clamped inverter for high-speed electric drives | |
| Itoh et al. | Novel unity power factor circuits using zero-vector control for single-phase input systems | |
| Ewanchuk et al. | Performance of a high-speed motor drive system using a novel multilevel inverter topology | |
| CN115868065B (en) | Method for heating battery, battery heating system and power utilization device | |
| WO2024087398A1 (en) | Transformer-based battery heating circuit, and electric vehicle | |
| US20230249564A1 (en) | Charging device and vehicle | |
| CN105071679A (en) | Five-level self-balanced inverter based on bridge switched capacitor module | |
| CN118074305A (en) | Uninterruptible power supply system | |
| CN218228714U (en) | Battery heating circuit and electric vehicle based on transformer | |
| Choudhury et al. | Modified DC-link voltage balancing algorithm for a 3-level neutral point clamped (NPC) traction inverter based electric vehicle PMSM drive | |
| Rizet et al. | A simplified resonant pole for three-level soft-switching PFC rectifier used in UPS | |
| Dube et al. | A Multilevel Three-Phase Integrated AC-DC Bidirectional Resonant Converter for BESS | |
| Lin et al. | Analysis and implementation of a single-phase capacitor-clamped inverter with simple structure | |
| Sharma et al. | A-source Inverter-fed PMSM drive with fault-tolerant capability for Electric Vehicles | |
| Tenner et al. | A comparison of Z-Source three-level NPC inverter versus Z-Source two-level inverter | |
| de Souza et al. | Bidirectional dual active clamping push-pull dc-dc converter | |
| CN114555415A (en) | Motor, power system, control method and electric automobile | |
| KR101862517B1 (en) | Multi-phase inverter using independent-type multi H-bridge | |
| CN116505635B (en) | Power battery charging device and vehicle | |
| CN215870891U (en) | High-voltage intelligent power saving device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Country or region after: China Address after: No. 36 Longying Road, Shilou Town, Panyu District, Guangzhou City, Guangdong Province Applicant after: GAC AION NEW ENERGY AUTOMOBILE Co.,Ltd. Address before: No. 36 Longying Road, Shilou Town, Panyu District, Guangzhou City, Guangdong Province Applicant before: GAC AION New Energy Vehicle Co.,Ltd. Country or region before: China |