Battery self-heating method, electronic equipment and storage medium

Abstract

The invention provides a battery self-heating method, electronic equipment and a storage medium, and the method comprises the steps: calculating a DC component of a motor current based on a demand torque and a battery self-heating demand; determining a high-frequency current component, wherein the high-frequency current component is an alternating current component; superposing the high-frequency alternating-current component and the direct-current component to enable the motor current to carry the high-frequency alternating-current component; the motor is controlled to heat the battery based on the motor current, the direct-current component is generated through control of a direct-current voltage vector in a DQ coordinate system, and the high-frequency current component is generated through control of a high-frequency alternating-current voltage superposed on the direct-current voltage vector in the DQ coordinate system. According to the invention, the battery can be heated in a driving state.

Description

Technical Field

[0001] The present application relates to the field of battery heating, and in particular to a battery self-heating method, electronic device and storage medium. Background Art

[0002] Electric vehicle power batteries have poor performance at low temperatures and need to be heated quickly to improve the user experience. Battery AC heating technology (also known as battery self-heating technology, battery pulse heating technology) refers to the method of passing AC power to the battery, using the internal resistance of the battery to generate heat, and heating the battery thermally. It has the advantages of high heating power, uniform heating, and high heating efficiency. It is an important low-temperature battery heating technology.

[0003] At present, the existing battery AC heating technology requires that the motor is in a stationary state, that is, the existing battery AC heating technology cannot heat the battery while the vehicle is in motion. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a battery self-heating method, an electronic device and a storage medium, so as to achieve heating of the battery while driving.

[0005] In a first aspect, the present invention provides a battery self-heating method, the method comprising:

[0006] Calculating a DC component of the motor current based on the required torque and the battery self-heating requirement;

[0007] Determine the high-frequency current component, which is the alternating current component;

[0008] Superimposing a high-frequency AC component with a DC component so that the motor current carries a high-frequency AC component;

[0009] The motor is controlled to heat the battery based on the motor current, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system.

[0010] The method of the first aspect of the present application can calculate the DC component of the motor current based on the required torque and the battery self-heating demand, and determine the high-frequency current component, which is the AC current component, and then the high-frequency AC component can be superimposed on the DC component so that the motor current carries the high-frequency AC component, so that the motor can be controlled to heat the battery based on the motor current, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system. Compared with the prior art, the present application can meet the heating and torque requirements of the driving process through the DC component in the motor current, thereby keeping the vehicle in the driving state. At the same time, the high-frequency AC component in the motor current can cause the motor winding energy storage and the motor output power to change at a high frequency, thereby generating high-frequency AC power on the DC bus side of the inverter, thereby charging the battery through the high-frequency AC power, and finally realizing the charging of the battery in the driving state.

[0011] In an optional embodiment, the DC component includes a D-axis DC component and a Q-axis DC component, and the high-frequency AC component includes a D-axis AC component and a Q-axis AC component, wherein the D-axis AC component is superimposed on the D-axis DC component, and the Q-axis AC component is superimposed on the Q-axis DC component.

[0012] In an alternative embodiment, the torque generated by the DC component is equal to the required torque.

[0013] In an optional embodiment, the DC component of the motor current is calculated based on the required torque and the battery self-heating requirement, including:

[0014] determining a preselected current operating point in a maximum torque current ratio line based on the required torque and the battery self-heating requirement;

[0015] Determine the isotorque line for the preselected current operating point;

[0016] Determine the field weakening current point or the field increasing current point based on the equal torque line of the preselected current working point;

[0017] From the field weakening current point or the field increasing current point, a current operating point whose current amplitude meets the preset conditions is selected as the DC component of the motor current.

[0018] In an optional embodiment, the high-frequency AC voltage superimposed on the DC voltage vector in the DQ coordinate system is generated by alternating changes in the first voltage vector and the second voltage vector in the DQ coordinate system, wherein the first voltage vector is located on the maximum available voltage boundary, and the second voltage vector is located within the maximum available voltage boundary, and the maximum available voltage boundary is the voltage limit of the inverter output to the motor limited by the DC bus voltage, and:

[0019] U dqL =2U dq0–U dqH ;

[0020] U dqL represents the second voltage vector, U dqH represents the first voltage vector, and Udq0 is the DC component.

[0021] In an optional embodiment, the method further includes: obtaining, by experiment or simulation, a U which makes the fluctuation amplitude of the motor winding energy storage reach a maximum value by adopting an approximate simplified mathematical model. dqH .

[0022] In an optional embodiment, the fundamental frequency of the high-frequency current component is equal to 10% to 300% of the resonant frequency of the parallel resonant circuit, wherein the parallel resonant circuit is composed of the inverter DC bus capacitor, the stray inductance between the battery and the inverter, and the battery internal resistance.

[0023] The second aspect of the present application discloses a battery self-heating device, the device comprising:

[0024] A first calculation module, used for calculating a DC component of the motor current based on a required torque and a battery self-heating requirement;

[0025] A determination module, used to determine a high-frequency current component, where the high-frequency current component is an alternating current component;

[0026] A second calculation module is used to superimpose the high-frequency AC component and the DC component so that the motor current carries the high-frequency AC component;

[0027] A control module is used to control the motor to heat the battery based on the motor current, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system.

[0028] In a third aspect, the present invention provides an electronic device, comprising:

[0029] Processor; and

[0030] The memory is configured to store machine-readable instructions, and when the instructions are executed by the processor, the battery self-heating method according to any one of the aforementioned embodiments is executed.

[0031] In a fourth aspect, the present invention provides a storage medium storing a computer program, wherein the computer program is executed by a processor to implement a battery self-heating method according to any one of the aforementioned embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is a schematic flow chart of a battery self-heating method disclosed in an embodiment of the present application;

[0034] Figure 2 This is a schematic diagram of the relationship between the DC side current in a driving state disclosed in an embodiment of the present application;

[0035] Figure 3 It is a schematic diagram of a DQ axis current trajectory after superimposing an AC component disclosed in an embodiment of the present application;

[0036] Figure 4 It is a schematic diagram of an equal torque line disclosed in an embodiment of the present application;

[0037] Figure 5 It is a schematic diagram of a voltage vector possible range disclosed in an embodiment of the present application;

[0038] Figure 6 It is another schematic diagram of the possible range of voltage vector disclosed in the embodiment of the present application;

[0039] Figure 7 This is a calculation result diagram when a DC component is located on an MTPA line, as disclosed in an embodiment of the present application;

[0040] Figure 8 This is a calculation result diagram when I d = -200A disclosed in an embodiment of the present application;

[0041] Fig. 9 This is a calculation result diagram when I d = -400A disclosed in an embodiment of the present application;

[0042] Fig.10 This is a calculation result diagram when I d = -600A disclosed in an embodiment of the present application;

[0043] Fig.11 It is a structural schematic diagram of a battery self-heating device disclosed in an embodiment of the present application;

[0044] Fig.12 It is a structural schematic diagram of an electronic device disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0045] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0046] Embodiment 1

[0047] See also Figure 1 , Figure 1 is a flow chart of a battery self-heating method disclosed in an embodiment of the present application, such as Figure 1 As shown, the method of the embodiment of the present application includes the following steps:

[0048] 101. Calculate a DC component of the motor current based on the required torque and the battery self-heating requirement;

[0049] 102. Determine a high-frequency current component, where the high-frequency current component is an alternating current component;

[0050] 103. Superimpose the high-frequency AC component and the DC component so that the motor current carries the high-frequency AC component;

[0051] 104. Controlling the motor to heat the battery based on the motor current, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system.

[0052] The method of the embodiment of the present application can calculate the DC component of the motor current based on the required torque and the battery self-heating demand, and determine the high-frequency current component, which is the AC current component, and then the high-frequency AC component can be superimposed on the DC component so that the motor current carries the high-frequency AC component, so that the motor can be controlled to heat the battery based on the motor current, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system. Compared with the prior art, the present application can meet the heating and torque requirements of the driving process through the DC component in the motor current, thereby keeping the vehicle in the driving state. At the same time, the high-frequency AC component in the motor current can cause the motor winding energy storage and the motor output power to change at a high frequency, thereby generating high-frequency AC power on the DC bus side of the inverter, thereby charging the battery through the high-frequency AC power, and finally realizing the charging of the battery in the driving state.

[0053] In the embodiment of the present application, for step 101, the required torque represents the torque value required by the vehicle, wherein the torque required by the vehicle can be obtained through an on-board controller, and the on-board controller can be determined by detecting the degree of depression of the power pedal.

[0054] In the embodiment of the present application, for step 101, the battery self-heating requirement refers to the temperature value required to heat the battery, wherein the temperature can be determined based on the user's power response requirement and the ambient temperature.

[0055] In the embodiment of the present application, for step 101, the motor current is used as the operating current of the vehicle motor, wherein the vehicle motor is operated under the motor current so that the motor can heat the battery while driving.

[0056] In the embodiment of the present application, with respect to step 101 , the DC component of the motor current refers to the DC current in the motor current.

[0057] In the embodiment of the present application, with respect to step 102, the high frequency in the high frequency current component may generally refer to a frequency range between 1 kHz and 5 kHz. Of course, this frequency range is only an example and may be determined according to actual usage.

[0058] In the embodiment of the present application, with respect to step 102 , the AC current component refers to the AC component in the motor current.

[0059] In an embodiment of the present application, for step 104, the motor current can be controlled by a motor controller, for example, the motor controller generates the motor current by outputting a voltage to the motor, wherein the motor controller outputs a voltage to the motor including a DC voltage vector in the DQ coordinate system and a high-frequency AC voltage superimposed on the DC voltage vector in the DQ coordinate system.

[0060] In the embodiment of the present application, the DQ coordinate system, also called the dq coordinate system or the rotating coordinate system, is a special two-dimensional coordinate system. In the DQ coordinate system, there are usually two axes: the d axis and the q axis. The two axes are orthogonal, that is, they are perpendicular to each other. The characteristic of the DQ coordinate system is that it can rotate with a certain reference system such as the rotor of a motor, so it is also called a rotating coordinate system.

[0061] For the embodiments of the present application, the principle is as follows:

[0062] See also Figure 2 , Figure 2 This is a schematic diagram of the DC side current relationship in a driving state disclosed in an embodiment of the present application. Figure 2 For the convenience of analysis, the internal resistance of the motor winding is omitted, and the dynamic relationship equations of the voltage (Ud, Uq), electromagnetic torque Te, winding energy storage E and current of the permanent magnet synchronous motor are as follows:

[0063]

[0064] Furthermore, by superimposing the AC current component (Formula 4) on the DC component of the DQ axis, the energy storage fluctuation power of the motor winding can be calculated as:

[0065]

[0066] Hypothesis I d,AC ,I q,ACThe fundamental frequency of the two AC components is f h , then we can get:

[0067]

[0068] Among them, E 1 ' is the derivative of the AC component of the current (fundamental frequency f h ) and the DC component, its fundamental wave frequency is naturally f h , and I d,AC ,I q,AC The fundamental frequency is the same; E 2 ' is the product of the AC component and its own derivative, and the fundamental frequency is 2f h , is I d,AC ,I q,AC Twice the fundamental frequency. Based on this, it can be seen that the energy storage of the motor winding fluctuates at this time.

[0069] Similarly, by superimposing the AC current component on the DC component of the DQ axis, the motor output torque can be calculated as:

[0070]

[0071] Where T e,DC is the DC component of the torque, T e,AC is the AC component of torque. I q,AC I d,AC The mean and fluctuation parts of this multiplication term.

[0072] Based on the above calculation formula, it can be seen that there is AC fluctuation in the motor output torque at this time; by adjusting Id,DC and Iq,DC, the average output torque of the motor can be controlled.

[0073] Therefore, according to the law of conservation of energy, the power on the DC side of the three-phase inverter bridge = the variable power of the motor energy storage + the mechanical energy output by the motor, that is:

[0074] P Inv =E′+T e ω e …Formula 9;

[0075] According to the conversion relationship between power and current, we can get:

[0076]

[0077] See also Figure 3 , Figure 3 Schematic diagram of a DQ axis current trajectory after superimposing an AC component disclosed in an embodiment of the present application. Figure 3In the DQ coordinate system shown, the equal winding energy storage line (solid line) and the equal torque line (dashed line) are drawn. When the DQ axis current is superimposed with the AC component, the trajectory of the current in the DQ coordinate system will appear as a Lissajous figure, as shown in Figure 3 The elliptical trajectory in the figure is shown (it is only a schematic diagram, and it can actually be any other closed curve shape). It can be seen that the winding energy storage and output torque at each point on the current trajectory are different. With the periodic oscillation of the current, the winding energy storage and motor output torque also oscillate periodically, thus forming an oscillating current on the DC side of the inverter. The average torque on the current trajectory is the torque that the motor can currently output, so it does not affect the output of the actual vehicle torque.

[0078] In summary, by superimposing the AC component on the DQ axis current, an AC current can appear on the DC side of the inverter. Part of this AC current comes from the fluctuation of the motor winding energy storage, and the other part comes from the fluctuation of the output torque. Obviously, this AC current can be used to heat the battery, thereby achieving heating of the battery while driving.

[0079] In an optional embodiment, the DC component includes a D-axis DC component and a Q-axis DC component, and the high-frequency AC component includes a D-axis AC component and a Q-axis AC component, wherein the D-axis AC component is superimposed on the D-axis DC component, and the Q-axis AC component is superimposed on the Q-axis DC component.

[0080] In the above optional implementation manner, the expression for superimposing the high-frequency AC component and the DC component is:

[0081] I d =I d,DC +I d,AC ;

[0082] I q =I q,DC +I q,AC ;

[0083] Among them, I d Indicates the D-axis current, l d,DC Indicates the D-axis DC component, I d,AC represents the D-axis AC component, and I q Indicates Q-axis current, I q,DC Indicates the Q-axis DC component, I q,AC Represents the Q-axis AC component.

[0084] As can be known, the high-frequency AC component includes a D-axis AC component and a Q-axis AC component, wherein the D-axis AC component is superimposed on the D-axis DC component, and the Q-axis AC component is superimposed on the Q-axis DC component.

[0085] In the embodiment of the present application, as an optional implementation, the torque generated by the DC component is equal to the required torque, and the torque requirement can be met by the DC component.

[0086] In the embodiment of the present application, as an optional implementation, the DC component of the motor current is calculated based on the required torque and the battery self-heating requirement, including the following sub-steps:

[0087] determining a preselected current operating point in a maximum torque current ratio line based on the required torque and the battery self-heating requirement;

[0088] Determine the isotorque line for the preselected current operating point;

[0089] Determine the field weakening current point or the field increasing current point based on the equal torque line of the preselected current working point;

[0090] From the field weakening current point or the field increasing current point, a current operating point whose current amplitude meets the preset conditions is selected as the DC component of the motor current.

[0091] For the above optional implementation, in order to achieve the purpose of heating the battery as quickly as possible, I Inv,AC The larger the better. Since the vehicle is in a relatively low speed most of the time, the fluctuation current caused by the output torque fluctuation is not large and can generally be ignored. For a typical electric vehicle "battery-inverter-motor" system, the system can obtain I d,DC or I q,DC Generally significantly greater than I d,AC or I q,AC Therefore, the fluctuation of DC current is mainly caused by the change of winding energy storage, that is:

[0092]

[0093] From formula 4, we can see that we should try to increase I d,DC ,I q,DC The absolute value of I d,DC ,I q,DC It is also necessary to consider the requirements for normal torque output. Generally, at low speeds, the motor current operates on the MTPA (Max Torque per Amper) line. In order to increase I d,DC ,I q,DC The absolute value of , it is necessary to deviate the working point from the MTPA line and move it on the equal torque line, where the equal torque line is as follows Figure 4 As shown, Figure 4 It is a schematic diagram of an equal torque line disclosed in an embodiment of the present application.

[0094] Further, in Figure 4 If Id If it moves in the direction of increasing, it is the magnetizing working point. d It is preferred to move in the direction of magnetic weakening, because the DC voltage ratio required to maintain the DC component of the current will be smaller, so there will be more voltage available to generate I d,AC and I q,AC , thereby further increasing I Inv,AC Of course, the magnetization operating point may be selected for other reasons, such as the motor harmonic noise may be lower at the magnetization operating point.

[0095] As an example, several sets of calculation data are given below. The assumptions in the calculation are as shown in Table 1. Based on the assumptions, the calculation result graph is obtained, which includes Figure 7 , Figure 8 and Fig. 9 , Fig.10 Among them, Figure 7 This is a calculation result diagram when a DC component is located on an MTPA line, disclosed in an embodiment of the present application. Figure 8 This is a calculation result diagram when Id=-200A disclosed in an embodiment of the present application. Fig. 9 This is a calculation result diagram when Id=-400A disclosed in an embodiment of the present application. Fig.10 This is a calculation result diagram of I d = -600A disclosed in the embodiment of this application. Figure 7 , Figure 8 and Fig. 9 , Fig.10 The left figure shows the contour map of winding energy storage, MTPA line, MTPV line and different ΔU dqH The corresponding AC current peak point trajectory and optimal ΔU dqH The corresponding AC current peak point (the point where the corresponding energy storage reaches the maximum value Emax and the minimum value Emin). In the calculation result diagram, the right side diagram is the voltage limit diagram and the optimal ΔU dqH Vector.

[0096] It can be seen that under the typical working condition of 5000rpm, by adjusting the working current point in the direction of weak magnetic field, the AC current can be increased from about 90A to more than 400A. The current of 400A is enough to quickly heat the battery.

[0097] parameter significance Numeric parameter significance Numeric <![CDATA[L d ]]> D-axis inductance 120uH Udc Bus voltage 400V <![CDATA[L q ]]> Q-axis inductance 310uH Cdc Bus Capacitor 500uF <![CDATA[φ m ]]> Permanent magnet flux number 0.055Wb L Cable inductance 5uH <![CDATA[f h ]]> AC component fundamental frequency 3.18kHz r Battery internal resistance 50mΩ n Motor speed 5000rpm <![CDATA[p n ]]> Motor pole pairs 4 Tm Motor mechanical torque 100Nm

[0098] Table 1

[0099] In an optional embodiment, the high-frequency AC voltage superimposed on the DC voltage vector in the DQ coordinate system is generated by alternating changes in the first voltage vector and the second voltage vector in the DQ coordinate system, wherein the first voltage vector is located on the maximum available voltage boundary, and the second voltage vector is located within the maximum available voltage boundary, and the maximum available voltage boundary is the voltage limit of the inverter output to the motor limited by the DC bus voltage, and:

[0100] U dqL =2U dq0 –U dqH ;

[0101] U dqL represents the second voltage vector, U dqH represents the first voltage vector, U dq0 is the DC component.

[0102] With respect to the above optional implementation mode, for a determined I d,DC and I q,DC , in order to increase I Inv,AC , we need to increase I d,AC or I q,AC The rate of change over time, and I d,AC and I q,AC The rate of change is proportional to the applied voltage, that is:

[0103]

[0104] Corresponding to the AC and DC components of the DQ axis current, the DQ axis voltage also has AC and DC components:

[0105]

[0106] Furthermore, if Figure 5 As shown, (U d ,U q ) The magnitude of the voltage vector is limited by the inverter DC bus voltage. d , U q In the coordinate system, it is represented by a unit circle (overmodulation is not considered), where: Figure 5 Schematic diagram of a voltage vector range disclosed in the embodiment of the present application. After the alternating voltage is applied, the actual voltage vector will be about (U d,DC ,U q,DC ) is symmetrical, so after adding the AC component, (U d ,U q )The possible range of the voltage vector is shown in area S1 in the figure.

[0107] Furthermore, in order to maximize (U d,AC ,U q,AC) of the fundamental wave component, preferably let (U d,AC ,U q,AC ) is composed of two vectors of the same magnitude and opposite directions. d ,U q ) voltage vector is reflected as alternating between two vectors, one of which (U dqH ) On the voltage boundary of the gray area, another U dqL in U dqH About d,DC ,U q,DC ) symmetrical position, that is:

[0108]

[0109] However, see Figure 6 ,like Figure 6 As shown, ΔU dqH Can change freely on a circular arc, that is, ΔU dqH Vector relative U dq,DC The rotation angle θ can also be changed. According to formula 12, for a certain I d,DC and I q,DC , there exists an optimal θ such that I Inv,AC In a specific solution, the optimal ΔU can be determined by calibration. dqH It should be noted that Figure 6 This is another schematic diagram of the possible range of voltage vector disclosed in an embodiment of the present application.

[0110] In an optional embodiment, the method further includes: obtaining, by experiment or simulation, a U which makes the fluctuation amplitude of the motor winding energy storage reach a maximum value by adopting an approximate simplified mathematical model. dqH .

[0111] In an embodiment of the present application, as an optional implementation, the fundamental frequency of the high-frequency current component is equal to 10% to 300% of the resonant frequency of the parallel resonant circuit, wherein the parallel resonant circuit is composed of the inverter DC bus capacitor, the stray inductance between the battery and the inverter, and the battery internal resistance.

[0112] For this optional implementation, due to I inv,AC The main frequency component is E 1 ', its fundamental frequency is the same as the fundamental frequency of the AC current, combined with Figure 2 Yes, if the fundamental frequency of the AC current is close to the resonant frequency of the resonant circuit, I inv,AC Amplification is achieved through the resonance of the resonant current.

[0113] Embodiment 2

[0114] See also Fig.11 , Fig.11 is a schematic diagram of the structure of a battery self-heating device disclosed in an embodiment of the present application, such as Fig.11 As shown, the device of the embodiment of the present application includes the following functional modules:

[0115] A first calculation module 201, used to calculate a DC component of a motor current based on a required torque and a battery self-heating requirement;

[0116] A determination module 202 is used to determine a high-frequency current component, where the high-frequency current component is an alternating current component;

[0117] A second calculation module 203, used for superimposing the high-frequency AC component and the DC component so that the motor current carries the high-frequency AC component;

[0118] The control module 204 is used to control the motor to heat the battery based on the motor current, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system.

[0119] The device of the embodiment of the present application can calculate the DC component of the motor current and determine the high-frequency current component based on the required torque and the battery self-heating demand by executing the battery self-heating method of the embodiment of the present application. The high-frequency current component is an AC current component, and then the high-frequency AC component can be superimposed on the DC component so that the motor current carries the high-frequency AC component, so that the motor can heat the battery based on the motor current control motor, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system. Compared with the prior art, the present application can meet the heating and torque requirements of the driving process through the DC component in the motor current, thereby keeping the vehicle in the driving state. At the same time, the high-frequency AC component in the motor current can cause the motor winding energy storage and the motor output power to change at a high frequency, thereby generating high-frequency AC power on the DC bus side of the inverter, thereby charging the battery through the high-frequency AC power, and finally realizing the charging of the battery in the driving state.

[0120] Embodiment 3

[0121] See also Fig.12 , Fig.12 is a schematic diagram of the structure of an electronic device disclosed in an embodiment of the present application, such as Fig.12 As shown, the electronic device of the embodiment of the present application includes:

[0122] Processor 301; and

[0123] The memory 302 is configured to store machine-readable instructions, and when the instructions are executed by the processor, the battery self-heating method according to any one of the aforementioned embodiments is executed.

[0124] The electronic device of the embodiment of the present application can calculate the DC component of the motor current based on the required torque and the battery self-heating demand, and determine the high-frequency current component by executing the battery self-heating method of the embodiment of the present application. The high-frequency current component is an AC current component, and then the high-frequency AC component can be superimposed on the DC component so that the motor current carries the high-frequency AC component, so that the motor can heat the battery based on the motor current control motor, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system. Compared with the prior art, the present application can meet the heating and torque requirements of the driving process through the DC component in the motor current, thereby keeping the vehicle in the driving state. At the same time, the high-frequency AC component in the motor current can cause the motor winding energy storage and the motor output power to change at a high frequency, thereby generating high-frequency AC power on the DC bus side of the inverter, thereby charging the battery through the high-frequency AC power, and finally realizing the charging of the battery in the driving state.

[0125] Embodiment 4

[0126] An embodiment of the present application provides a storage medium, wherein the storage medium stores a computer program, and the computer program is executed by a processor as a battery self-heating method in any of the aforementioned implementations.

[0127] The storage medium of the embodiment of the present application can calculate the DC component of the motor current based on the required torque and the battery self-heating demand, and determine the high-frequency current component by executing the battery self-heating method of the embodiment of the present application. The high-frequency current component is an AC current component, and then the high-frequency AC component can be superimposed on the DC component so that the motor current carries the high-frequency AC component, so that the motor can heat the battery based on the motor current control motor, wherein the DC component is generated by the DC voltage vector control in the DQ coordinate system, and the high-frequency current component is generated by the high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system. Compared with the prior art, the present application can meet the heating and torque requirements of the driving process through the DC component in the motor current, thereby keeping the vehicle in the driving state. At the same time, the high-frequency AC component in the motor current can cause the motor winding energy storage and the motor output power to change at a high frequency, thereby generating high-frequency AC power on the DC bus side of the inverter, thereby charging the battery through the high-frequency AC power, and finally realizing the charging of the battery in the driving state.

[0128] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0129] In addition, the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0130] Furthermore, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0131] It should be noted that if the function is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0132] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0133] The above are only embodiments of the present application and are not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.

Claims

1. A battery self-heating method, characterized in that: The method comprises: Calculating a DC component of the motor current based on the required torque and the battery self-heating requirement; Determining a high-frequency current component, wherein the high-frequency current component is an alternating current component; superimposing the high-frequency AC component and the DC component so that the motor current carries the high-frequency AC component; The motor is controlled based on the motor current to heat the battery, wherein the DC component is generated by a DC voltage vector control in a DQ coordinate system, and the high-frequency current component is generated by a high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system.

2. The method according to claim 1, characterized in that The DC component includes a D-axis DC component and a Q-axis DC component, and the high-frequency AC component includes a D-axis AC component and a Q-axis AC component, wherein the D-axis AC component is superimposed on the D-axis DC component, and the Q-axis AC component is superimposed on the Q-axis DC component.

3. The method according to claim 1, characterized in that The torque generated by the DC component is equal to the required torque.

4. The method according to claim 1, characterized in that The method of calculating the DC component of the motor current based on the required torque and the battery self-heating requirement includes: determining a preselected current operating point in a maximum torque-to-current ratio line based on the required torque and the battery self-heating requirement; Determining an isotorque line of the preselected current operating point; Determine a magnetic weakening current point or a magnetic increasing current point based on the equal torque line of the preselected current working point; From the magnetic weakening current point or the magnetic increasing current point, a current operating point whose current amplitude meets a preset condition is selected as the DC component of the motor current.

5. The method according to claim 4, characterized in that The high-frequency AC voltage superimposed on the DC voltage vector in the DQ coordinate system is generated by alternating changes in the first voltage vector and the second voltage vector in the DQ coordinate system, wherein the first voltage vector is located on the maximum available voltage boundary, and the second voltage vector is located within the maximum available voltage boundary, and the maximum available voltage boundary is a limitation of the voltage output to the motor by the inverter limited by the DC bus voltage, and: IN dqL =2U dq0 -IN dqH ; U dqL represents the second voltage vector, U dqH represents the first voltage vector, U dq0 is the DC component.

6. The method according to claim 5, characterized in that The method further comprises: obtaining, by experiment or simulation, a U which is selected to make the fluctuation amplitude of the motor winding energy storage reach a maximum value by adopting an approximate simplified mathematical model. dqH .

7. The method according to claim 5, characterized in that The fundamental frequency of the high-frequency current component is equal to 10% to 300% of the resonant frequency of the parallel resonant circuit, wherein the parallel resonant circuit is composed of the inverter DC bus capacitor, the stray inductance between the battery and the inverter, and the battery internal resistance.

8. A battery self-heating device, characterized in that: The device comprises: A first calculation module, used for calculating a DC component of the motor current based on a required torque and a battery self-heating requirement; A determination module, used to determine a high-frequency current component, wherein the high-frequency current component is an alternating current component; A second calculation module, used for superimposing the high-frequency AC component and the DC component so that the motor current carries the high-frequency AC component; A control module is used to control the motor to heat the battery based on the motor current, wherein the DC component is generated by DC voltage vector control in a DQ coordinate system, and the high-frequency current component is generated by high-frequency AC voltage control superimposed on the DC voltage vector in the DQ coordinate system.

9. An electronic device, characterized in that: include: processor; as well as A memory configured to store machine-readable instructions, wherein when the instructions are executed by the processor, the battery self-heating method according to any one of claims 1 to 7 is executed.

10. A storage medium, characterized in that: The storage medium stores a computer program, and the computer program is executed by a processor to implement the battery self-heating method according to any one of claims 1 to 7.

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