On-board charger and electric vehicle

Abstract

An on-board charger and an electric vehicle are provided, the on-board charger including a microprocessor (4) and a DC module (2), a first sampling point (A1) is provided between the DC module (2) and a storage battery (3), a second sampling point (A2) is provided between the storage battery (3) and the microprocessor (4), the microprocessor (4) is configured to execute the steps of obtaining a first voltage value and a current value at the first sampling point (A1) and a second voltage value at the second sampling point (A2), and marking the connection between the storage battery (3) and the DC module (2) as disconnected and recording a first difference value between the second voltage value and the first voltage value when the first voltage value is greater than the second voltage value and the current value is less than a predetermined current threshold.

Description

Technical Field

[0001] (Cross - reference to related applications) This disclosure claims the priority of Chinese Patent Application No. 202111157823.1, entitled "On - board Charger and Electric Vehicle", filed with the China National Intellectual Property Administration on September 29, 2021, and all of its contents are incorporated herein by reference.

[0002] This disclosure relates to the technical field of electric vehicles, and particularly to on - board chargers and electric vehicles.

Background Art

[0003] With the development of science and technology, environmentally friendly and energy - saving electric vehicles are playing a role in replacing fuel vehicles. However, for the popularization of electric vehicles, when the connection between the DC module for charging the battery and the battery is disconnected, it is not timely detected, but the battery needs to continuously supply power externally. Therefore, there are some problems such as the possibility of power shortage in the battery during driving, resulting in low driving safety and high driving risk.

Summary of the Invention

Problems to be Solved by the Invention

[0004] This disclosure aims to solve at least one of the technical problems existing in the prior art. For this reason, the first object of this disclosure is to provide an on - board charger having advantages such as high disconnection detection accuracy.

Means for Solving the Problems

[0005] To achieve the above object, the on - board charger according to an embodiment of the first aspect of this disclosure includes a DC module and a microprocessor. The DC module has a first terminal connected to the power battery and a second terminal connected to the battery, and a first sampling point is provided between the battery and the DC module. The microprocessor is connected to the storage battery, a second sampling point is provided between the microprocessor and the storage battery, and is respectively connected to the first sampling point and the second sampling point. The microprocessor is configured to execute the steps of obtaining a first voltage value and a current value of the first sampling point, and a second voltage value of the second sampling point. When the first voltage value is greater than the second voltage value and the current value is less than a predetermined current threshold, mark that the connection between the storage battery and the DC module is disconnected, and record a first difference value between the second voltage value and the first voltage value.

[0006] In the present invention, a first sampling point is provided between the DC module and the storage battery, and a second sampling point is provided between the storage battery and the microprocessor. Therefore, the present invention determines whether the connection between the storage battery and the DC module is disconnected based on the comparison result of the voltage information sampled at the first sampling point and the voltage information sampled at the second sampling point, and the current information sampled at the first sampling point, thereby improving the disconnection detection accuracy. When the connection between the storage battery and the DC module of the electric vehicle is disconnected, it is still possible to avoid continuing to run for a long time, improve the driving safety, and reduce the driving risk.

[0007] A second object of the present disclosure is to provide an electric vehicle including an on-board charger according to the first object.

[0008] Some of the additional aspects and advantages of the present disclosure are shown in the following description, some will become apparent in the following description, or will be understood by implementing the present disclosure.

Brief Description of the Drawings

[0009] The above and / or additional aspects and advantages of the present disclosure will become apparent and be more easily understood by describing the embodiments with reference to the following drawings.

[0010]

Figure 1

Figure 2

Embodiments for Carrying out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be described in detail. The embodiments described with reference to the drawings are exemplary. Hereinafter, embodiments of the present disclosure will be described in detail.

[0012] As shown in FIG. 1, an embodiment of the present disclosure provides an on-board charger. The on-board charger includes a DC module 2 and a microprocessor 4. The first terminal of the DC module 2 is connected to the power battery 1, the storage battery 3 is connected to the second terminal of the DC module 2, a first sampling point A1 is provided between the storage battery 3 and the DC module 2, the microprocessor 4 is connected to the storage battery 3, a second sampling point A2 is provided between the microprocessor 4 and the storage battery 3, and the microprocessor 4 is connected to the first sampling point A1 and the second sampling point A2 respectively.

[0013] Note that in FIG. 1, the present application describes the low-voltage control circuit of the on-board charger with arrows.

[0014] The microprocessor 4 is configured to execute steps of obtaining the first voltage value and current value of the first sampling point and the second voltage value of the second sampling point, and when the first voltage value is greater than the second voltage value and the current value is less than a predetermined current threshold, marking that the connection between the storage battery 3 and the DC module 2 is disconnected and recording the first difference value between the second voltage value and the first voltage value.

[0015] In the present invention, a first sampling point A1 is provided between the DC module 2 and the storage battery 3, and a second sampling point A2 is provided between the storage battery 3 and the microprocessor 4. Therefore, the present invention determines whether the connection between the storage battery 3 and the DC module 2 is disconnected based on the comparison result between the voltage information sampled at the first sampling point A1 and the voltage information sampled at the second sampling point A2, and the current information sampled at the first sampling point, thereby improving the disconnection detection accuracy. When the connection between the storage battery 3 and the DC module 2 of the electric vehicle is disconnected, it is still possible to avoid continuing to run for a long time, improve the running safety, and reduce the running risk.

[0016] In order to further improve the accuracy of disconnection judgment, based on this embodiment, in other embodiments, the microprocessor 4 further When it is marked that the connection between the storage battery 3 and the DC module 2 is disconnected, by controlling the DC module 2, the step of increasing the output voltage of the DC module 2, the third voltage value of the first sampling point A1, and the fourth voltage value of the second sampling point A2 Acquisition And obtaining a second difference value between the fourth voltage value and the third voltage value, and when the difference value between the second difference value and the first difference value is equal to or greater than a predetermined threshold, determining that the connection between the storage battery 3 and the DC module 2 is disconnected, and when the difference value between the second difference value and the first difference value is less than the predetermined threshold, determining that the connection between the storage battery 3 and the DC module 2 is not disconnected.

[0017] In this embodiment, by controlling the DC module 2, the output voltage of the DC module 2 is increased, and based on the resampled voltage sampling information, it is further confirmed whether the connection between the DC module 2 and the storage battery 3 is disconnected. When the difference value between the second difference value and the first difference value is smaller than a predetermined threshold value, it is confirmed that the connection between the DC module 2 and the storage battery 3 is not disconnected, avoiding misjudgment of disconnection. That is, when the actual power supply current is very small and the impedance of the power supply circuit is large, resulting in the sampling voltage at the second sampling point being smaller than the sampling voltage at the first sampling point, misjudging that the connection between the DC module 2 and the storage battery 3 is disconnected is avoided, thereby further improving the disconnection detection accuracy. Also, when the difference value between the second difference value and the first difference value is greater than or equal to the predetermined threshold value, that is, the voltage information sampled at the first sampling point A1 increases with the increase in the voltage of the DC module, but the voltage information sampled at the second sampling point decreases with the continuation of power supply to the outside, resulting in an increase in the difference value between the second difference value and the first difference value, improving the judgment reliability of the disconnection between the storage battery 3 and the DC module 2.

[0018] Based on this embodiment, in other embodiments, the on-board charger further includes a PFC module 10 and a DC / DC module 11, and the PFC (Power Factor Correction, Power Factor Improvement Circuit) module 10 has its first terminal connected to the charging interface 12, its second terminal connected to the first terminal of the DC / DC module 11, and the second terminals of the DC / DC module 11 are respectively connected to the power battery 1 and the first terminal of the DC module 2.

[0019] As shown in FIG. 2, the charging interface 12 includes three L terminals and an N terminal. The PFC module 10 includes three inductors, a three-phase high-frequency bridge arm, and a single-phase power-frequency bridge arm. For each inductor, the first terminal is connected to one of the L terminals, the other end is connected to the midpoint of a single-phase high-frequency bridge arm, the N terminal is connected to the midpoint of the power-frequency bridge arm, the upper ends of the three-phase high-frequency bridge arm and the single-phase power-frequency bridge arm are commonly connected to form a first bus terminal, the lower ends of the three-phase high-frequency bridge arm and the single-phase power-frequency bridge arm are commonly connected to form a second bus terminal. The DC / DC module 11 has its first terminals connected to the first bus terminal and the second bus terminal respectively, and its second terminals connected to the first terminal of the DC module 2 and the power battery 1 respectively.

[0020] Specifically, the three L terminals include an L1 terminal, an L2 terminal, and an L3 terminal. The three inductors include a first inductor L1, a second inductor L2, and a third inductor L3. The three-phase high-frequency bridge arm includes a first-phase high-frequency bridge arm (Q1 + Q2), a second-phase high-frequency bridge arm (Q3 + Q4), and a third-phase high-frequency bridge arm (Q5 + Q6). For the first inductor L1, the first terminal is connected to the L1 terminal, and the second terminal is connected to the midpoint of the first-phase high-frequency bridge arm. For the second inductor L2, the first terminal is connected to the L2 terminal, and the second terminal is connected to the midpoint of the second-phase high-frequency bridge arm. For the third inductor L3, the first terminal is connected to the L3 terminal, and the second terminal is connected to the midpoint of the third-phase high-frequency bridge arm. The N terminal is connected to the midpoint of the power-frequency bridge arm (Q7 + Q8). The upper ends of the three-phase high-frequency bridge arm and the single-phase power-frequency bridge arm are commonly connected to form a first bus terminal, and the lower ends of the three-phase high-frequency bridge arm and the single-phase power-frequency bridge arm are commonly connected to form a second bus terminal.

[0021] The microprocessor 4 further includes steps of obtaining a first phase and a first effective voltage value corresponding to the first-phase bridge arm, a second phase and a second effective voltage value corresponding to the second-phase bridge arm, and a third phase and a third effective voltage value corresponding to the third-phase bridge arm, obtaining a first phase difference between the first phase and the second phase, a second phase difference between the second phase and the third phase, and a third phase difference between the third phase and the first phase, judging whether the external power supply is a single-phase power supply or a three-phase power supply based on the first phase difference, the second phase difference, the third phase difference, the first effective voltage value, the second effective voltage value, and the third effective voltage value, controlling to enter the single-phase charging mode when it is determined that the external power supply is a single-phase power supply, controlling to enter the three-phase charging mode when it is determined that the external power supply is a three-phase power supply, and is configured to execute the steps.

[0022] This embodiment supports both single-phase charging and three-phase charging. Also, compared with the related art, when identifying only by the phase difference, if the phase detection is abnormal, misjudgment will occur, or when identifying only by the effective voltage value, if the obtained effective voltage value is interfered, misjudgment will occur. Therefore, in this embodiment, by combining the phase difference and the effective voltage value to identify the single-phase charging / three-phase charging mode, when it cannot be accurately identified by the phase difference or the effective voltage value, further identification is performed by other identification methods, thereby improving the identification accuracy and further reducing the misjudgment rate.

[0023] In the above embodiment, judging whether the external power supply is a single-phase power supply or a three-phase power supply based on the first phase difference, the second phase difference, the third phase difference, the first effective voltage value, the second effective voltage value, and the third effective voltage value includes at least the following implementation situations (1) to (4).

[0024] (1) Identify between single-phase and three-phase by the phase difference first, and then identify between single-phase and three-phase by the effective voltage value.

[0025] Specifically, when identifying single-phase and three-phase by phase difference and neither identifying single-phase charging nor three-phase charging is realized by phase difference, identify single-phase and three-phase by the effective voltage value.

[0026] (2) After identifying single-phase and three-phase by the effective voltage value, identify single-phase and three-phase by phase difference.

[0027] Specifically, when identifying single-phase and three-phase by the effective voltage value and neither identifying single-phase charging nor three-phase charging is realized by the effective voltage value, identify single-phase and three-phase by phase difference.

[0028] (3) After identifying single-phase or three-phase by phase difference, identify single-phase and three-phase by the effective voltage value.

[0029] Specifically, when identifying single-phase by phase difference and the identification of single-phase charging is not realized by phase difference, identify single-phase and three-phase by the effective voltage value.

[0030] Also, when identifying three-phase by phase difference and the identification of three-phase charging is not realized by phase difference, identify single-phase and three-phase by the effective voltage value.

[0031] (4) After identifying single-phase or three-phase by the effective voltage value, identify single-phase and three-phase by phase difference.

[0032] Specifically, when identifying single-phase by the effective voltage value and the identification of single-phase charging is not realized by the effective voltage value, identify single-phase and three-phase by phase difference.

[0033] Also, when identifying three-phase by the effective voltage value and the identification of three-phase charging is not realized by the effective voltage value, identify single-phase and three-phase by phase difference.

[0034] Based on this embodiment, in other embodiments, The microprocessor 4 further A step of determining whether all of the first phase difference, the second phase difference, and the third phase difference satisfy a predetermined charging mode determination condition, and when any of the first phase difference, the second phase difference, and the third phase difference does not satisfy the predetermined charging mode determination condition, based on the first effective voltage value, the second effective voltage value, and the third effective voltage value, determining whether the external power supply is a single-phase power supply or a three-phase power supply.

[0035] In this embodiment, the predetermined charging mode determination condition includes a predetermined three-phase charging determination condition, and the predetermined three-phase charging determination condition is that all of the first phase difference, the second phase difference, and the third phase difference are within a predetermined phase range.

[0036] To explain the technical means of the present disclosure in more detail, the predetermined phase range may be set in advance or may be set in real time according to the needs of the user. Exemplarily, the predetermined phase range may be (105°, 125°).

[0037] Also, in this embodiment, the predetermined charging mode determination condition includes a predetermined single-phase charging determination condition, and the predetermined single-phase charging determination condition is that all of the first phase difference, the second phase difference, and the third phase difference are smaller than a predetermined phase threshold.

[0038] To explain the technical means of the present disclosure in more detail, the predetermined phase threshold may be set in advance or may be set in real time according to the needs of the user. Exemplarily, the predetermined phase threshold may be 10°.

[0039] In the identification of the single-phase / three-phase charging mode of this embodiment, in order to identify by the voltage effective value after identifying by the phase difference, when identifying by the phase difference, if the phase difference does not satisfy the predetermined three-phase charging determination condition, by directly abandoning the execution of the operation of "determining whether the phase difference satisfies the predetermined single-phase charging determination condition", when the phase difference cannot be identified (for example, open phase or abnormal phase detection), repeated execution of invalid operations is avoided, the identification process is simplified, and the identification speed is further improved.

[0040] Based on this embodiment, in other embodiments, when identifying by the phase difference, if the phase difference does not meet the predetermined single-phase charging determination condition, by directly abandoning the execution of the operation of "judging whether the phase difference meets the predetermined three-phase charging determination condition", when it cannot be identified by the phase difference (for example, open phase or abnormal phase detection), repeated execution of invalid operations is avoided, simplifying the identification process and further improving the identification speed.

[0041] Based on this embodiment, in other embodiments, the microprocessor 4 further judges whether it meets the predetermined single-phase judgment condition or the predetermined three-phase judgment condition based on the first effective voltage value, the second effective voltage value, and the third effective voltage value; when it is determined that the predetermined single-phase judgment condition is met, determines that the external power supply is a single-phase power supply; and when it is determined that the predetermined three-phase judgment condition is met, determines that the external power supply is a three-phase power supply.

[0042] In this embodiment, the predetermined three-phase judgment condition is that the first effective voltage value > the second effective voltage value > the third effective voltage value, and the third effective voltage value > the first predetermined voltage threshold value.

[0043] To explain the technical means of the present disclosure in more detail, the first predetermined voltage threshold value may be set in advance or may be set in real time according to the needs of the user. Exemplarily, the first predetermined voltage threshold value may be 150V.

[0044] Also, in this embodiment, the predetermined single-phase judgment condition is that the first effective voltage value > the second effective voltage value > the third effective voltage value, and the second effective voltage value < the second predetermined voltage threshold value.

[0045] To explain the technical means of the present disclosure in more detail, the second predetermined voltage threshold value may be set in advance or may be set in real time according to the needs of the user. Exemplarily, the second predetermined voltage threshold value may be 20V.

[0046] In the identification of the single-phase / three-phase charging mode of this embodiment, after identifying by the effective voltage value and then by the phase difference, when identifying by the effective voltage value, if the effective voltage value does not meet the predetermined single-phase judgment condition, the execution of the operation of "judging whether the effective voltage value meets the predetermined three-phase judgment condition" is directly abandoned. When the effective voltage value cannot be identified (for example, the effective voltage value detected due to signal interference of the hardware is abnormal), repeating the execution of invalid operations is avoided, the identification process is simplified, and the identification speed is further improved.

[0047] Also, when identifying by the effective voltage value, if the effective voltage value does not meet the predetermined three-phase judgment condition, the execution of the operation of "judging whether the effective voltage value meets the predetermined single-phase judgment condition" is directly abandoned. When the effective voltage value cannot be identified (for example, the effective voltage value detected due to signal interference of the hardware is abnormal), repeating the execution of invalid operations is avoided, the identification process is simplified, and the identification speed is further improved.

[0048] The electric vehicle according to the second aspect of the present disclosure includes the on-board charger described in the embodiment of the first aspect.

[0049] The specific principle and implementation method of the on-board charger of the electric vehicle according to the embodiment of the present disclosure are all the same as those of the embodiment of the first aspect, and the description is omitted here.

[0050] In addition, in the description of the present disclosure, the orientation or positional relationship indicated by terms such as "center", "longitudinal direction", "lateral direction", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial direction", "radial direction", "circumferential direction", etc. is based on the orientation or positional relationship shown in the drawings. It is only for facilitating the description of the present disclosure and simplifying the description, and does not indicate or imply that the shown device or component must have a specific orientation and be configured and operate in a specific orientation. Therefore, it should not be understood that the present disclosure is limited.

[0051] In the description of the present disclosure, unless otherwise clearly defined and limited, the terms "attachment", "connection", and "connection" should be understood in a broad sense. For example, they may be fixed connections, detachable connections, or integral connections, may be direct connections or connections through an intermediate medium, and may also be communications between two components. A person skilled in the art can understand the specific meanings of the above terms in the present disclosure according to the specific situation.

[0052] In the description of this specification, referring to the descriptions of terms such as "one embodiment", "several embodiments", "exemplary embodiments", "examples", "specific examples", or "several examples" means that the specific features, configurations, materials, or characteristics described in combination with the said embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the exemplary descriptions of the above terms are not necessarily limited to the same embodiment or example.

[0053] Although the embodiments of the present disclosure have been shown and described, a person skilled in the art can make various changes, corrections, substitutions, and modifications to these embodiments without departing from the principles and purposes of the present disclosure, and it can be understood that the scope of the present disclosure is limited by the claims and their equivalents.

Claims

1. An on-board charger including a DC module and a microprocessor, wherein a first terminal of the DC module is connected to a power battery, a second terminal of the DC module is connected to a storage battery, and a first sampling point is provided between the storage battery and the DC module; the microprocessor is connected to the storage battery, a second sampling point is provided between the microprocessor and the storage battery, and the microprocessor is connected to the first sampling point and the second sampling point; the microprocessor is configured to obtain a first voltage value and a current value of the first sampling point, and obtain a second voltage value of the second sampling point; when the first voltage value is greater than the second voltage value and the current value is less than a predetermined current threshold, mark that the connection between the storage battery and the DC module is disconnected, and record a first difference value between the second voltage value and the first voltage value. An on-board charger, characterized in that it is configured to perform the steps.

2. The microprocessor further: when it is marked that the connection between the storage battery and the DC module is disconnected, increase the output voltage of the DC module by controlling the DC module; obtain a third voltage value of the first sampling point and a fourth voltage value of the second sampling point, and obtain a second difference value between the fourth voltage value and the third voltage value; when the difference value between the second difference value and the first difference value is greater than or equal to a predetermined threshold, determine that the connection between the storage battery and the DC module is disconnected; when the difference value between the second difference value and the first difference value is less than the predetermined threshold, determine that the connection between the storage battery and the DC module is not disconnected. The on-board charger according to claim 1, characterized in that it is configured to perform the steps.

3. further including a power factor correction (PFC) module and a DC / DC module, The power factor improvement circuit module includes three inductors, a three-phase high-frequency bridge arm, and a single-phase power frequency bridge arm, and is connected to a charging interface including three L terminals and an N terminal. The first terminal of each inductor is connected to one L terminal, the other end of each inductor is connected to the midpoint of a single-phase high-frequency bridge arm, the N terminal is connected to the midpoint of the power frequency bridge arm. The upper ends of the three-phase high-frequency bridge arm and the single-phase power frequency bridge arm are commonly connected to form a first bus terminal, and the upper end of the three-phase high-frequency bridge arm and the lower end of the single-phase power frequency bridge arm are commonly connected to form a second bus terminal. The first terminal of the DC / DC module is connected to the first bus terminal and the second bus terminal, and the second terminal of the DC / DC module is connected to the first terminal of the DC module and the power battery. The microprocessor further includes steps of obtaining a first phase and a first effective voltage value corresponding to a first-phase bridge arm, a second phase and a second effective voltage value corresponding to a second-phase bridge arm, and a third phase and a third effective voltage value corresponding to a third-phase bridge arm. Steps of obtaining a first phase difference between the first phase and the second phase, a second phase difference between the second phase and the third phase, and a third phase difference between the third phase and the first phase. Based on the first phase difference, the second phase difference, the third phase difference, the first effective voltage value, the second effective voltage value, and the third effective voltage value, determine whether the external power supply is a single-phase power supply or a three-phase power supply. When it is determined that the external power supply is a single-phase power supply, steps of controlling to enter the single-phase charging mode. When it is determined that the external power supply is a three-phase power supply, steps of controlling to enter the three-phase charging mode, and is configured to execute the above, which is characterized by the on-board charger according to claim 1.

4. The microprocessor further Steps of determining whether any of the first phase difference, the second phase difference, and the third phase difference satisfies a predetermined charging mode determination condition. When any one of the first phase difference, the second phase difference, and the third phase difference does not satisfy the predetermined charging mode determination condition, based on the first effective voltage value, the second effective voltage value, and the third effective voltage value, determine whether the external power supply is a single-phase power supply or a three-phase power supply, and execute the step, the on-board charger according to claim 3, characterized in that.

5. The predetermined charging mode determination condition includes a predetermined three-phase charging determination condition, and the predetermined three-phase charging determination condition is that the first phase difference, the second phase difference, and the third phase difference are all within a predetermined phase range. The on-board charger according to claim 4, characterized in that.

6. The predetermined charging mode determination condition includes a predetermined single-phase charging determination condition, and the predetermined single-phase charging determination condition is that the first phase difference, the second phase difference, and the third phase difference are all smaller than a predetermined phase threshold value. The on-board charger according to claim 4, characterized in that.

7. The microprocessor further Based on the first effective voltage value, the second effective voltage value, and the third effective voltage value, determine whether to satisfy a predetermined single-phase determination condition or a predetermined three-phase determination condition, and When it is determined that the predetermined single-phase determination condition is satisfied, determine that the external power supply is a single-phase power supply, and When it is determined that the predetermined three-phase determination condition is satisfied, determine that the external power supply is a three-phase power supply, and execute the step, the on-board charger according to claim 3, characterized in that.

8. The predetermined three-phase determination condition is that the first effective voltage value > the second effective voltage value > the third effective voltage value > the first predetermined voltage threshold value. The on-board charger according to claim 7, characterized in that.

9. The predetermined single-phase determination condition is that the first effective voltage value > the second effective voltage value > the third effective voltage value, and the second effective voltage value < the second predetermined voltage threshold value. The on-board charger according to claim 7, characterized in that.

10. An electric vehicle, characterized by including the on-board charger according to any one of claims 1 to 9.

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