Safety protection circuit for recognizing ac and dc power supply based on chaoji charging interface and vehicle

Abstract

The application discloses a ChaoJi charging interface-based AC / DC power supply safety protection circuit and vehicle, realizes the accuracy of charging type identification after an AC or DC charging gun is inserted into a charging interface shared by AC and DC charging, and the circuit comprises an AC / DC identification circuit, a control unit, an AC switch and a DC switch; one end of the AC / DC identification circuit is used for being connected with a charging pile, for collecting input charging signals and identifying the AC / DC type of the charging signals; the other end of the AC / DC identification circuit is connected with the control unit; the control unit is further connected with the AC switch and the DC switch respectively, for controlling the on-off of the AC switch and the DC switch; and the AC switch and the DC switch are connected with a power battery respectively.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and in particular to a safety protection circuit for AC / DC power supply based on ChaoJi charging interface identification and a vehicle. Background Technology

[0002] With the increasing popularity of electric vehicles, the use of AC and DC charging stations is becoming more and more frequent. However, since the AC charging guns and DC charging guns of charging stations may look similar, and the AC charging interfaces and DC charging interfaces of electric vehicles may also look similar, users may accidentally plug the AC or DC charging gun into the incompatible charging interface, which may damage the vehicle's power battery or the charging station, or even cause safety hazards. Utility Model Content

[0003] In view of the above problems, this application provides a safety protection circuit and vehicle based on ChaoJi charging interface identification for AC / DC power supply, so as to effectively prevent the safety risks caused by incorrect insertion of AC / DC charging gun and AC / DC charging interface. The specific solution is as follows:

[0004] The first aspect of this application provides a safety protection circuit for AC / DC power supply based on ChaoJi charging interface identification, including: AC / DC identification circuit 10, control unit 30, AC switch K1 and DC switch K2;

[0005] One end of the AC / DC identification circuit 10 is connected to the charging pile to collect the input charging signal and identify the AC / DC type of the charging signal; the other end of the AC / DC identification circuit 10 is connected to the control unit 30.

[0006] The control unit 30 is also connected to AC switch K1 and DC switch K2 respectively, and is used to control the on and off of AC switch K1 and DC switch K2; AC switch K1 and DC switch K2 are respectively connected to the power battery.

[0007] In one possible implementation, AC charging and DC charging share a single ChaoJi charging interface.

[0008] In one possible implementation, the AC / DC identification circuit 10 is used to convert the input charging signal into a waveform and output it to the control unit 30. Different types of charging signals correspond to different converted output waveforms.

[0009] In one possible implementation, the AC / DC identification circuit 10 includes: a full-bridge rectifier circuit 11, a first resistor circuit 12, a second resistor circuit 13, and an optocoupler U1;

[0010] The input terminal of optocoupler U1 is connected in series with the first resistor circuit 12 and then connected to the output terminal of the full-bridge rectifier circuit 11; the first pin of the output terminal of optocoupler U1 is grounded, and the second pin of the output terminal of optocoupler U1 is connected to the power supply through the second resistor circuit 13.

[0011] The input terminal of the full-bridge rectifier circuit 11 is the input terminal of the AC / DC identification circuit 10;

[0012] The second pin of the output terminal of optocoupler U1 is the output terminal of AC / DC identification circuit 10.

[0013] In one possible implementation, the AC / DC identification circuit 10 further includes: a DC blocking capacitor C1; the DC blocking capacitor C1 is connected in series with the full-bridge rectifier circuit 11.

[0014] In one possible implementation, the AC / DC identification circuit 10 further includes a third resistor circuit 14; the third resistor circuit 14 is connected in series with the full-bridge rectifier circuit 11.

[0015] In one possible implementation, the AC / DC identification circuit 10 further includes: a first filter circuit; the first filter circuit is connected in parallel with the output terminal of the optocoupler U1.

[0016] In one possible implementation, the AC / DC identification circuit 10 further includes a second filter circuit; the second filter circuit is connected in parallel with the input terminal of the optocoupler U1.

[0017] In one possible implementation, the AC / DC identification circuit 10 further includes a limiting circuit; the limiting circuit is connected in parallel with the input terminal of the optocoupler U1.

[0018] In one possible implementation, the limiting circuit includes a limiting diode.

[0019] In one possible implementation, the AC / DC power supply safety protection circuit based on the ChaoJi charging interface identification further includes: a control guidance circuit 20;

[0020] The input terminal of the control guidance circuit 20 is used to connect to the charging pile and to process the input communication signal before outputting it to the control unit 30.

[0021] The second aspect of this application provides a vehicle, including: a ChaoJi charging interface identification AC / DC power supply safety protection circuit based on the first aspect or any implementation thereof.

[0022] By employing the above technical solution, this application improves the traditional charging circuit into a safety protection circuit based on the ChaoJi charging interface to identify AC / DC power supply. The ChaoJi charging interface, as a new generation of DC charging interface for electric vehicles, features speed, safety, and strong compatibility. The AC / DC identification circuit introduced on this basis uses the charging signal from the charging cable entering the ChaoJi charging interface as input to collect and identify the AC / DC type of the charging signal. The control unit then controls the on / off state of the charging line accordingly. This application effectively prevents the safety risks caused by incorrect insertion of the AC / DC charging gun and the AC / DC charging interface by introducing an intelligent AC / DC identification mechanism between the AC / DC charging gun and the AC / DC charging interface. Attached Figure Description

[0023] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the originals and elements are not necessarily drawn to scale.

[0024] Figure 1 A schematic diagram illustrating the evolution of a dual charging interface for an electric vehicle into a single charging interface, as provided in this application;

[0025] Figure 2 A schematic diagram of a single charging interface for an electric vehicle provided in this application;

[0026] Figure 3 A schematic diagram of a safety protection circuit for AC / DC power supply based on ChaoJi charging interface identification is provided in this application;

[0027] Figure 4 A schematic diagram of an AC / DC identification circuit provided in this application;

[0028] Figure 5 A voltage waveform diagram of an AC / DC identification circuit when an AC charging gun is inserted, provided in this application;

[0029] Figure 6 A voltage waveform diagram of an AC / DC identification circuit when a DC charging gun is inserted, as provided in this application;

[0030] Figure 7 A schematic diagram of another AC / DC identification circuit provided in this application;

[0031] Figure 8 A voltage waveform diagram of the AC / DC identification circuit when a DC charging gun is inserted, as provided in this application.

[0032] Figure 9 A schematic diagram of another AC / DC identification circuit provided in this application. Detailed Implementation

[0033] In order to ensure the accuracy of the citations and the fluency of reading, the key technical terms, abbreviations or acronyms used in the text are summarized and explained as follows:

[0034] DC / DC: Direct Current to Direct Current;

[0035] OBC: On-board Charger;

[0036] CC: Connection Confirm Function.

[0037] CP: Control Pilot Function.

[0038] With the booming development of the new energy vehicle industry, automakers are constantly optimizing vehicle performance to meet growing market demand and consumer expectations. In this process, electric vehicle charging technology has become one of the key factors driving industry development.

[0039] Traditional electric vehicles are generally equipped with interfaces for both AC and DC charging (see...). Figure 1 The diagram above shows AC charging interface 1 and DC charging interface 2, designed to meet charging needs in different scenarios. Since AC and DC charging guns on charging stations may look similar, and AC and DC charging interfaces on electric vehicles may also look similar, users may accidentally plug the AC charging gun into the DC charging interface or vice versa, potentially damaging the vehicle's battery or the charging station, and even posing a safety hazard.

[0040] Furthermore, considering that the AC charging and DC charging interfaces are arranged separately, this poses challenges to the weight, cost, and layout of the vehicle. The main issues are: the need to install both AC and DC charging interfaces and related wiring increases the layout and manufacturing costs of the vehicle, while also increasing the weight of the vehicle and affecting the driving range.

[0041] To save on overall vehicle cost, reduce overall vehicle weight, and facilitate vehicle layout, AC charging and DC charging share a single charging interface (see [link]). Figure 1Electric vehicles with a single charging interface (3) as shown in the diagram below have emerged. The single charging interface 3 of the electric vehicle is designed to accept both AC and DC charging. When the AC or DC charging gun of the charging station is plugged in, the charging circuit after the charging interface 3 (the charging interface 3 can be regarded as the input terminal for vehicle charging) relies on the internal control and guidance circuit to automatically identify the charging type (AC charging or DC charging) and switch to the corresponding charging mode.

[0042] The charging type identification of the control and guidance circuit can be achieved based on CC resistor identification and / or CP voltage signal identification, as described in detail below:

[0043] The cables inside charging port 3 include charging cables and communication cables. The charging cables can transmit both AC and DC power, while the communication cables include CC and CP cables. When the owner wants to charge via AC, simply insert the AC charging gun into the electric vehicle's charging port 3; when the owner wants to charge via DC, simply insert the DC charging gun into the electric vehicle's charging port 3 (e.g., ...). Figure 2 In the scenario shown, the car owner wants to use DC charging, so they insert the DC charging gun 5 of charging station 4 into the only charging port 3 of the electric vehicle (the AC charging gun 6 of charging station 4 is not used). When an AC or DC charging gun is inserted into charging port 3, the CC cable and CP cable between the charging station and the electric vehicle are immediately connected. Then, the control and guidance circuit inside the charging circuit performs CC resistance identification and CP voltage signal identification. The CC resistance identification result and the CP voltage signal identification result are both output to the control unit inside the charging circuit. The control unit identifies the charging type based on the CC resistance identification result and / or the CP voltage signal identification result, specifically:

[0044] When AC charging is detected (i.e., when the AC charging gun is inserted, or when AC power enters the charging cable), the control unit controls the electric vehicle to start AC charging mode (i.e., slow charging mode). At this time, the electric vehicle will use the OBC to convert AC power into DC power to charge the electric vehicle's power battery.

[0045] When DC charging is detected (i.e., when the DC charging gun is inserted, or when DC power enters the charging cable), the control unit controls the electric vehicle to start DC charging mode (i.e., fast charging mode). At this time, the electric vehicle will directly use DC power to charge the power battery. Electric vehicles contain two types of batteries: a high-voltage battery, also known as the power battery, and a low-voltage battery. The low-voltage battery is charged by the power battery through a DC / DC converter.

[0046] However, the quality of charging piles on the market varies greatly, which can lead to misjudgments of the charging type through CC resistor identification; similarly, identification through CP voltage signal can also be misjudged due to external interference. The inaccuracy of the control guidance circuit in identifying the charging type makes it unable to effectively prevent the risks caused by incorrect insertion of AC / DC charging guns into AC / DC charging interfaces (i.e., when an AC charging gun is inserted into charging interface 3, the control guidance circuit misidentifies the AC charging gun as a DC charging gun, causing the control unit to activate the DC charging mode of the electric vehicle; or, when a DC charging gun is inserted into charging interface 3, the control guidance circuit misidentifies the DC charging gun as an AC charging gun, causing the control unit to activate the AC charging mode of the electric vehicle).

[0047] In summary, whether it is an electric vehicle with separate AC charging and DC charging interfaces or an electric vehicle with a single charging interface for both AC and DC charging, there is a problem of not being able to effectively prevent the safety risks caused by misconnection of AC / DC charging guns to AC / DC charging interfaces.

[0048] To effectively prevent safety risks caused by incorrect insertion of AC / DC charging guns and AC / DC charging interfaces, embodiments of this application will... Figure 1 or Figure 2 The traditional charging circuit has been improved to a safety protection circuit based on ChaoJi charging interface identification of AC / DC power supply. By introducing an AC / DC intelligent identification mechanism between the AC / DC charging gun and the AC / DC charging interface, the charging type can be accurately identified, thereby effectively preventing the safety risks caused by incorrect insertion of the AC / DC charging gun and the AC / DC charging interface.

[0049] The following description, in conjunction with the accompanying drawings, describes an AC / DC power supply safety protection circuit based on ChaoJi charging interface identification, according to an embodiment of this application. Those skilled in the art will recognize that, with technological advancements and the emergence of new scenarios, the technical solutions provided in this application are equally applicable to similar technical problems.

[0050] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.

[0051] The terminology used in the following embodiments is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to also include expressions such as “one or more,” unless the context clearly indicates otherwise. It should also be understood that in the embodiments of this application, “one or more” means one, two, or more; “and / or” describes the relationship between related objects, indicating that three relationships may exist; for example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character “ / ” generally indicates that the preceding and following related objects are in an “or” relationship.

[0052] See Figure 3 ( Figure 3 (The illustration only takes the example of AC charging and DC charging sharing a single charging interface.) This application provides a safety protection circuit for AC / DC power supply based on ChaoJi charging interface identification, including: AC / DC identification circuit 10, control unit 30, and two controllable switches; the two controllable switches are AC switch K1 and DC switch K2, respectively.

[0053] The electric vehicle can share a single charging interface 3 for both AC and DC charging. This interface is a ChaoJi charging interface, a next-generation DC charging interface for electric vehicles, characterized by its speed, safety, and strong compatibility. The charging interface 3 is equipped with charging cables (i.e., L / DC+ and N / DC- cables; when the AC charging gun is inserted, these two cables are used as the live wire (L) and neutral wire (N), respectively; when the DC charging gun is inserted, these two cables are used as the positive wire (DC+) and negative wire (DC-), respectively). After exiting the charging interface 3, the charging cable branches into two lines: one line connects to the power battery via AC switch K1 and OBC, and the other line connects to the power battery via DC switch K2. Figure 3 In this context, HV+ and HV- represent the positive and negative terminals of the power battery, respectively.

[0054] Alternatively, the AC charging interface and DC charging interface of the electric vehicle can be set separately. Both the AC charging interface and the DC charging interface are ChaoJi charging interfaces. The AC charging interface is equipped with a charging cable, which is led out from the AC charging interface and connected to the power battery through the AC switch K1 and OBC. The DC charging interface is also equipped with a charging cable, which is led out from the DC charging interface and connected to the power battery through the DC switch K2.

[0055] When AC charging and DC charging share a single charging interface 3, the input terminal of the AC / DC identification circuit 10 is connected to the charging cable in the charging interface 3, and then used to connect to the charging pile. When the AC charging interface and DC charging interface are set separately, the input terminal of the AC / DC identification circuit 10 is connected to the charging cables in the AC charging interface and DC charging interface respectively, and then used to connect to the charging pile. The AC / DC identification circuit 10 is used to collect the charging signal input on the charging cable and identify the AC / DC type of the charging signal. The output terminal of the AC / DC identification circuit 10 is connected to the input terminal of the control unit 30.

[0056] The output of control unit 30 is connected to the control terminals of AC switch K1 and DC switch K2 (in Figure 3 For the sake of simplicity, the connection lines between the output terminal of the control unit 30 and the control terminals of the AC switch K1 and the DC switch K2 are not shown in the diagram.

[0057] When AC charging and DC charging share a single charging interface 3, the control unit 30 determines, based on the identification result of the AC / DC identification circuit 10, whether to close the DC switch K2 and keep the AC switch K1 open, or to close the AC switch K1 and keep the DC switch K2 open. When the AC charging interface and the DC charging interface are set separately, the control unit 30 determines, based on the identification result of the AC / DC identification circuit 10, whether to close the DC switch K2 and keep the AC switch K1 open, or to close the AC switch K1 and keep the DC switch K2 open, or to keep both the AC switch K1 and the DC switch K2 open.

[0058] The AC / DC identification circuit 10 directly acquires the input charging signal to identify the AC / DC type, compared to... Figure 2 The traditional identification method based on CC resistance or CP voltage signal is more reliable. It does not rely on easily interfered or error-prone CC resistance values ​​or CP voltage signals, thus reducing misjudgments caused by differences in charging pile quality or external interference, improving the accuracy of charging type identification, and effectively preventing safety risks caused by incorrect insertion of AC / DC charging guns and AC / DC charging interfaces. Compared to… Figure 1 In the absence of an AC / DC intelligent identification mechanism, introducing such a mechanism accurately identifies the charging type, effectively preventing safety risks caused by incorrect insertion of the AC / DC charging gun and AC / DC charging interface.

[0059] In one possible implementation, see still Figure 3 For cases where AC charging and DC charging share a single charging interface 3, the charging interface 3 is also equipped with communication cables (i.e., CC cable and CP cable); the AC / DC power supply safety protection circuit based on ChaoJi charging interface identification also includes a control guidance circuit 20;

[0060] The input terminal of the control guidance circuit 20 is connected to the communication cable, and the output terminal of the control guidance circuit 20 is connected to the input terminal of the control unit 30. The control guidance circuit 20 is used to process the input communication signal and output it to the control unit 30 (the control guidance circuit 20 and the control unit 30 can be integrated inside the OBC or set up independently). Figure 3 The diagram is drawn using an example where AC and DC charging share a single charging interface 3, and the control guidance circuit 20 and control unit 30 are both integrated inside the OBC. This integration inside the OBC can reduce the overall size of the safety protection circuit for AC / DC power supply identification based on the ChaoJi charging interface and reduce its assembly complexity, etc.

[0061] The following is combined with Figure 3 The working principle of the circuit after the introduction of the control guidance circuit 20 is described in detail:

[0062] When the AC or DC charging gun is inserted into the charging interface 3, the CC cable and CP cable between the charging pile and the electric vehicle are connected. Then, the control guide circuit 20 performs CC resistance identification and CP voltage signal identification. The CC resistance identification result and the CP voltage signal identification result are both output to the control unit 30. The control unit 30 preliminarily identifies whether the current charging type is AC charging or DC charging based on the CC resistance identification result and / or the CP voltage signal identification result.

[0063] Meanwhile, when the AC or DC charging gun is inserted into the charging interface 3, the AC / DC identification circuit 10 performs waveform conversion and output on the electrical signal entering the charging cable. Different types of electrical signals correspond to different conversion output waveforms. The conversion output waveform is also output to the control unit 30. The control unit 30 uses the conversion output waveform to initially identify whether the current charging type is AC charging or DC charging.

[0064] The control unit 30 uses the two preliminary identification results to verify each other and obtain the final identification result. For example, if both preliminary identification results are DC charging, the final identification is DC charging; if both preliminary identification results are AC charging, the final identification is AC charging; if the two preliminary identification results are inconsistent, the charging type cannot be accurately confirmed, so electric vehicle charging is prohibited.

[0065] When the control unit 30 ultimately identifies DC charging, it controls the DC switch K2 to close, at which point the electric vehicle will directly use DC power to charge the power battery; when the control unit 30 ultimately identifies AC charging, it controls the AC switch K1 to close, at which point the electric vehicle will use the OBC to convert AC power to DC power to charge the power battery.

[0066] In summary, the embodiments of this application introduce both an AC / DC identification circuit 10 and a control guidance circuit 20 into the AC / DC power supply safety protection circuit based on the ChaoJi charging interface identification. The control unit 30 uses the output signals of both the AC / DC identification circuit 10 and the control guidance circuit 20 as criteria to identify the charging type. The application of dual criteria improves the accuracy of charging type identification, thereby improving charging safety.

[0067] In any of the above-mentioned AC / DC power supply safety protection circuits based on ChaoJi charging interface identification, AC switch K1 is an AC relay, and DC switch K2 is a DC relay.

[0068] In any of the above-mentioned AC / DC power supply safety protection circuits based on ChaoJi charging interface identification, the AC / DC identification circuit 10 is used to convert the input signal into a waveform and output it to the control unit 30. Different types of input signals correspond to different converted output waveforms.

[0069] In one possible implementation, such as Figure 4 As shown, the AC / DC identification circuit 10 used to realize the above waveform conversion function includes: a full-bridge rectifier circuit 11, a first resistor circuit 12, a second resistor circuit 13, and an optocoupler (full name: optocoupler) U1;

[0070] The optocoupler U1 mainly consists of a light source and a light receiver. The light source is typically a light-emitting diode (LED), and the light receiver can be a photodiode, phototransistor, etc. The light source and light receiver are assembled in the same sealed housing and isolated from each other by a transparent insulator. The pins of the light source are the input terminals of the optocoupler U1, and the pins of the light receiver are the output terminals of the optocoupler U1. When there is an electrical signal at the input terminal and the voltage of the electrical signal exceeds the forward voltage drop u of the light source... th When the light source emits light, the light signal is received by the light receiver and converted into an electrical signal (that is, the light receiver is turned on under light irradiation), thus realizing the conversion between electricity and light and electricity.

[0071] The input terminal of optocoupler U1 is connected in series with the first resistor circuit 12 and then connected to the output terminal of the full-bridge rectifier circuit 11; the first pin of the output terminal of optocoupler U1 is grounded, and the second pin of the output terminal of optocoupler U1 is connected to the power supply VCC through the second resistor circuit 13.

[0072] The input terminal of the full-bridge rectifier circuit 11 is the input terminal of the AC / DC identification circuit 10;

[0073] The second pin of the output terminal of optocoupler U1 is the output terminal TO_MCU of AC / DC identification circuit 10.

[0074] Figure 4 The working principle of the AC / DC identification circuit 10 shown is as follows:

[0075] When the AC charging gun is plugged in, see Figure 5 The curve shown illustrates the voltage variation with ωt (ωt represents the phase angle of the sine wave): The AC current u entering the charging cable... o1 The current is rectified into pulsating DC by the full-bridge rectifier circuit 11. o2 pulsating DC u o2 A near-continuous pulse waveform (also known as a "bun wave"); the first resistor circuit 12 and the light source of the optocoupler U1 interact with the pulsating DC current u. o2 Perform series voltage division; when the voltage division on the light source exceeds the on-state voltage drop u of the light source. th When the light source is turned on, the light receiver of optocoupler U1 is also turned on. At this time, the voltage u at the output terminal TO_MCU of AC / DC identification circuit 10 is... o3 The voltage is pulled down to approximately zero (the forward voltage drop of the light receiver is very small, essentially zero); when the voltage drop across the light source does not exceed the forward voltage drop u of the light source. th When the light source is not conducting, the photodetector of optocoupler U1 is not conducting, and the voltage u is [value missing]. o3 It is equal to the power supply voltage VCC; therefore, when the AC charging gun is plugged in, the voltage u o3 It is a pulse signal.

[0076] When the DC charging gun is plugged in, see Figure 6 The curve showing the voltage change with ωt: The DC current entering the charging cable is rectified by the full-bridge rectifier circuit 11, and the output waveform is still a constant DC current u. o4 DC power u o4 The voltage value exceeds the forward voltage drop u of the light source. th Therefore, the light source of optocoupler U1 is always on, the light receiver is always on, and the voltage u at the output terminal TO_MCU of AC / DC identification circuit 10 is constant. o3 It is a constant DC signal that is approximately equal to zero voltage.

[0077] Therefore, the control unit 30 determines the voltage u o3 By determining whether the signal is a pulse signal or a constant DC signal (with a voltage value approximately equal to zero), the charging type can be identified as AC charging or direct charging.

[0078] The resistor circuits in the embodiments of this application can be a single resistor or a series-parallel combination of multiple resistors, which can be set according to actual needs. In one possible implementation, see still Figure 4 The first resistor circuit 12 includes resistors R1, R2, R3 and R4, which are connected in series.

[0079] In one possible implementation, see still Figure 6 The second resistor circuit 13 includes resistor R5, which is a pull-up resistor.

[0080] In one possible implementation, such as Figure 7 As shown, any of the AC / DC identification circuits 10 provided above may further include: a DC blocking capacitor C1, which is connected in series with the full-bridge rectifier circuit 11.

[0081] The DC blocking capacitor C1 has the characteristic of "passing AC and blocking DC" (i.e., DC current cannot pass through the DC blocking capacitor, but AC current can pass through it). Therefore, after introducing the DC blocking capacitor C1, the voltage waveform of the AC / DC identification circuit 10 when the AC charging gun is inserted is similar to... Figure 5 There is no difference in the input; however, when the DC charging gun is inserted, the input terminal of the optocoupler U1 cannot receive voltage, so the light source of the optocoupler U1 is not conducting and the light receiver is not conducting. At this time, the voltage u at the output terminal TO_MCU of the AC / DC identification circuit 10 is... o3 A constant DC signal equal to the power supply voltage VCC, such as Figure 8 As shown. Therefore, the control unit 30 determines the voltage u o3 The charging type can be identified by whether it is a pulse signal or a constant DC signal (voltage value equal to the power supply voltage VCC).

[0082] In one possible implementation, see Figure 9 The AC / DC identification circuit 10 provided above may further include: a third resistor circuit 14; the third resistor circuit 14 is connected in series with the full-bridge rectifier circuit 11 to reduce the voltage drop across the full-bridge rectifier circuit 11, which is beneficial for the selection and protection of components in the full-bridge rectifier circuit 11. See also... Figure 9 The third resistor circuit 14 includes, for example, resistor R6.

[0083] In one possible implementation, any of the AC / DC identification circuits 10 provided above may further include: a first filter circuit; this first filter circuit is connected in parallel with the output terminal of the optocoupler U1, and is used to filter the output signal of the optocoupler U1, reducing signal fluctuations caused by noise and interference, making the output signal of the optocoupler U1 more stable, thereby enhancing the reliability of the control unit 30 in data processing. See still Figure 9 The first filter circuit includes, for example, capacitor C2.

[0084] In one possible implementation, any of the AC / DC identification circuits 10 provided above may further include: a second filter circuit; this second filter circuit is connected in parallel with the output terminal of the optocoupler U1, and is used to filter the input signal of the optocoupler U1, reducing signal fluctuations caused by noise and interference, making the input signal of the optocoupler U1 more stable, thereby enhancing the operational reliability of the optocoupler U1. See also... Figure 9 The second filter circuit includes, for example, capacitor C3.

[0085] In one possible implementation, any of the AC / DC identification circuits 10 provided above may further include: a limiting circuit; this limiting circuit is connected to the input terminal of the optocoupler U1, and is used to limit the voltage amplitude of the input signal of the optocoupler U1 within the required range to prevent the voltage amplitude from being too high and causing overvoltage damage to the optocoupler U1. See also... Figure 9 The limiting circuit includes, for example, a limiting diode D1; compared with other complex limiting circuits, the limiting diode D1 has a simpler structure, is easier to implement and maintain, and has a lower cost.

[0086] In addition, this application embodiment also provides a vehicle, including: any of the above-mentioned AC / DC power supply safety protection circuits based on ChaoJi charging interface identification.

[0087] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the embodiments of this application. Therefore, the embodiments of this application are not to be limited to the embodiments shown herein, but are to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A safety protection circuit for AC / DC power supply based on ChaoJi charging interface identification, characterized in that, include: AC / DC identification circuit (10), control unit (30), AC switch (K1) and DC switch (K2); One end of the AC / DC identification circuit (10) is used to connect to the charging pile to collect the input charging signal and identify the AC / DC type of the charging signal; the other end of the AC / DC identification circuit (10) is connected to the control unit (30). The control unit (30) is also connected to the AC switch (K1) and the DC switch (K2) respectively, and is used to control the on and off of the AC switch (K1) and the DC switch (K2); the AC switch (K1) and the DC switch (K2) are respectively connected to the power battery.

2. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 1, characterized in that, AC charging and DC charging share the same ChaoJi charging interface.

3. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 1 or 2, characterized in that, The AC / DC identification circuit (10) is used to convert the input charging signal into a waveform and output it to the control unit (30). Different types of charging signals correspond to different conversion output waveforms.

4. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 3, characterized in that, The AC / DC identification circuit (10) includes: a full-bridge rectifier circuit (11), a first resistor circuit (12), a second resistor circuit (13), and an optocoupler (U1); The input terminal of the optocoupler (U1) is connected in series with the first resistor circuit (12) and then connected to the output terminal of the full-bridge rectifier circuit (11); The first pin of the output terminal of the optocoupler (U1) is grounded, and the second pin of the output terminal of the optocoupler (U1) is connected to the power supply through the second resistor circuit (13); The input terminal of the full-bridge rectifier circuit (11) is the input terminal of the AC / DC identification circuit (10); The second pin of the output terminal of the optocoupler (U1) is the output terminal of the AC / DC identification circuit (10).

5. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 3, characterized in that, The AC / DC identification circuit (10) further includes: a DC blocking capacitor (C1); The DC blocking capacitor (C1) is connected in series with the full-bridge rectifier circuit (11).

6. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 3, characterized in that, The AC / DC identification circuit (10) further includes: a third resistor circuit (14); The third resistor circuit (14) is connected in series with the full-bridge rectifier circuit (11).

7. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 3, characterized in that, The AC / DC identification circuit (10) further includes: a first filter circuit; The first filter circuit is connected in parallel with the output terminal of the optocoupler (U1).

8. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 3, characterized in that, The AC / DC identification circuit (10) further includes: a second filter circuit; The second filter circuit is connected in parallel with the input terminal of the optocoupler (U1).

9. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 3, characterized in that, The AC / DC identification circuit (10) further includes: a limiting circuit; The limiting circuit is connected in parallel with the input terminal of the optocoupler (U1).

10. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 9, characterized in that, The limiting circuit includes a limiting diode.

11. The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification according to claim 2, characterized in that, The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification also includes: a control guidance circuit (20); The input terminal of the control guidance circuit (20) is used to connect to the charging pile and to process the input communication signal and output it to the control unit (30).

12. A vehicle, characterized in that, include: The AC / DC power supply safety protection circuit based on ChaoJi charging interface identification as described in any one of claims 1 to 11.

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