New energy vehicle high-voltage control circuit and vehicle

Abstract

The utility model provides a new energy automobile high-voltage control circuit which is characterized by comprising a first pre-charging loop, a second pre-charging loop, a first capacitor C1, a second capacitor C2, a first micro-control unit MCU1 and a second micro-control unit MCU2. The input side of the first pre-charging loop and the input side of the second pre-charging loop are both used for being connected with the positive electrode of a power battery. The output side of the first pre-charging loop is sequentially connected with a first capacitor C1 and a first micro-control unit MCU1. The output side of the second pre-charging loop is connected with a second capacitor C2 and a second micro-control unit MCU2 in sequence; the positive electrode of the first capacitor C1 and the positive electrode of the second capacitor C2 are in short circuit. When the first pre-charging loop or the second pre-charging loop breaks down, the vehicle can still complete starting control through the remaining pre-charging loops, and the continuity of starting and running of the vehicle is ensured.

Description

Technical Field

[0001] This application relates to the field of new energy vehicle safety technology, and in particular to a high-voltage control circuit and vehicle for new energy vehicles. Background Technology

[0002] Electric vehicle high-voltage controllers or control modules / units mainly include DCAC modules, DC-DC modules, AC-DC modules, and power distribution units (PDUs). DCAC modules include motor controllers (MCUs) and auxiliary drive motor controllers, such as high-voltage steering motor controllers, air pump motor controllers, and air conditioning compressor controllers. DC-DC modules include common buck DC-DC, boost DC-DC, isolated DC-DC, and fast-charging DC-DC types. AC-DC modules mainly include slow-charging and OBC (On-Board Charger) types. A common feature of DCAC, DC-DC, AC-DC, and PDU high-voltage controllers is that they contain high-voltage capacitors, which are designed primarily for filtering, frequency modulation, isolation, and time control.

[0003] When these high-voltage controllers or control modules / units are powered on for the first time in the vehicle, the capacitors need to be charged first. The capacitor charging voltage is an exponential function with a base greater than 1 (base e), and the charging voltage rises extremely quickly. This rapid charging speed leads to excessive current, which can easily cause faults such as the main positive contactor sticking or the fuse being damaged. Therefore, it is necessary to design high-voltage power-on and power-off circuits for the high-voltage controller to reduce the current passing through the main positive contactor or fuse, extend the capacitor charging time, and protect the high-voltage controller from damage caused by large current surges during power-on. Electric vehicles have many controllers, and each controller needs to be pre-charged. Traditional control methods are mainly divided into two categories: The first category is to pre-charge all controllers simultaneously on the same circuit, that is, there is only one pre-charging circuit, and all controllers are pre-charged at the same time. The second category is multi-circuit pre-charging, where each controller is pre-charged individually or certain accessories are pre-charged together.

[0004] In the process of implementing the embodiments of this application, at least the following technical problems were found in the related art:

[0005] When the pre-charging circuit fails, the controller and load connected to the faulty pre-charging circuit will not work, affecting vehicle operation. Utility Model Content

[0006] This application provides a high-voltage control circuit and vehicle for new energy vehicles to solve the problem that when a pre-charging circuit fails, the controller or load connected to the faulty pre-charging circuit will not work, affecting vehicle operation.

[0007] In a first aspect, embodiments of this application provide a high-voltage control circuit for a new energy vehicle, including: a first pre-charge circuit, a second pre-charge circuit, a first capacitor C1, a second capacitor C2, a first microcontroller unit MCU1, and a second microcontroller unit MCU2;

[0008] The input sides of both the first pre-charge circuit and the second pre-charge circuit are used to connect to the positive terminal of the power battery. The output side of the first pre-charge circuit is connected to the first capacitor C1 and the first microcontroller unit MCU1 in sequence. The output side of the second pre-charge circuit is connected to the second capacitor C2 and the second microcontroller unit MCU2 in sequence. The positive terminals of the first capacitor C1 and the second capacitor C2 are short-circuited.

[0009] In one possible implementation, the high-voltage control circuit for the new energy vehicle further includes a first main positive contactor K1 and a second main positive contactor K3;

[0010] The first pre-charge circuit is connected in parallel with the first main positive contactor K1, and the second pre-charge circuit is connected in parallel with the second main positive contactor K3;

[0011] The input sides of the first main positive contactor K1 and the second main positive contactor K3 are both used to connect to the positive terminal of the power battery. The output side of the first main positive contactor K1 is connected to the first capacitor C1 and the first microcontroller unit MCU1 in sequence; the output side of the second main positive contactor K3 is connected to the second capacitor C2 and the second microcontroller unit MCU2 in sequence.

[0012] The first pre-charge circuit includes a contactor K2 and a resistor R1 connected in series; the second pre-charge circuit includes a contactor K4 and a resistor R2 connected in series; the input terminal of the contactor K2 is the input side of the first pre-charge circuit, and the input terminal of the contactor K4 is the input side of the second pre-charge circuit.

[0013] In one possible implementation, both the first capacitor C1 and the second capacitor C2 are thin-film capacitors.

[0014] In one possible implementation, the first precharge circuit further includes a diode D1 for backflash protection, connected in series between the resistor R1 and the contactor K2; in another possible implementation, the second precharge circuit further includes a diode D2 for backflash protection, connected in series between the resistor R2 and the contactor K4.

[0015] In one possible implementation, the first precharge circuit further includes a fuse F1 connected between the first microcontroller unit MCU1 and the first main positive contactor K1;

[0016] The second precharge circuit also includes a fuse F2, which is connected between the second microcontroller unit MCU2 and the second main positive contactor K3.

[0017] In one possible implementation, the output side of the first microcontroller unit MCU1 is connected to the first drive motor M1; the output side of the second microcontroller unit MCU2 is connected to the second drive motor M2.

[0018] In one possible implementation, both the first precharge circuit and the second precharge circuit further include one or more precharge branches, the output side of which is connected to a branch load; each branch load is connected in parallel with the first microcontroller unit MCU1 or each branch load is connected in parallel with the second microcontroller unit MCU2.

[0019] In one possible implementation, both the first precharge circuit and the second precharge circuit further include a branch fuse disposed on the precharge branch, the branch fuse being connected between the main positive contactor and the branch load; the main positive contactor includes a first main positive contactor K1 or a second main positive contactor K3, and the branch fuse corresponds one-to-one with the branch load.

[0020] In one possible implementation, when the branch load is an electric heater PTC, a contactor is also provided on the pre-charge branch connected to the electric heater PTC, and the contactor is connected between the main positive contactor and the branch fuse.

[0021] Secondly, embodiments of this application provide a vehicle, including the new energy vehicle high-voltage control circuit, vehicle power battery and drive motor as described in the first aspect or any possible implementation of the first aspect, wherein the drive motor includes a first drive motor M1 and a second drive motor M2.

[0022] The high-voltage control circuit of the new energy vehicle is connected between the power battery and the drive motor.

[0023] This application provides a high-voltage control circuit and vehicle for a new energy vehicle. The high-voltage control circuit comprises a first pre-charge circuit, a second pre-charge circuit, a first capacitor C1, a second capacitor C2, a first microcontroller unit (MCU1), and a second microcontroller unit (MCU2). The first and second pre-charge circuits carry different loads, and the first and second microcontroller units (MCU1 and MCU2) control these different loads, ensuring stability during the high-voltage power-on and power-off processes of the new energy vehicle. The output side of the first pre-charge circuit is sequentially connected to the first capacitor C1 and the first microcontroller unit (MCU1), and the output side of the second pre-charge circuit is sequentially connected to the second capacitor C2 and the second microcontroller unit (MCU2). The first capacitor C1 and the second capacitor C2 are short-circuited. When either pre-charge circuit fails, the other pre-charge circuit charges the capacitors C1 and C2 corresponding to the first microcontroller unit (MCU1) and the second microcontroller unit (MCU2), thereby ensuring that the controllers and loads corresponding to both pre-charge circuits can operate normally, ensuring the continuity of vehicle startup and operation. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a high-voltage control circuit for a new energy vehicle provided in an embodiment of this application;

[0026] Figure 2 This is a schematic diagram of the structure of a high-voltage control circuit for a new energy vehicle provided in another embodiment of this application;

[0027] Figure 3 This is a schematic diagram of the structure of a high-voltage control circuit for a new energy vehicle provided in another embodiment of this application;

[0028] Figure 4 This is a schematic diagram of the structure of a high-voltage control circuit for a new energy vehicle provided in another embodiment of this application;

[0029] Figure 5 This is a schematic diagram of the structure of a high-voltage control circuit for a new energy vehicle provided in another embodiment of this application;

[0030] Figure 6 This is a schematic diagram of the current flow direction of a high-voltage control circuit for a new energy vehicle provided in an embodiment of this application;

[0031] Figure 7This is a schematic diagram of the current flow direction of a high-voltage control circuit for a new energy vehicle provided in another embodiment of this application. Detailed Implementation

[0032] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0033] The terms "first," "second," etc., 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 data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0034] Unless otherwise stated, the term "multiple" means two or more. The character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B means: A or B. The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0035] The terms used in this application are for describing embodiments only and are not intended to limit the claims. As used in the description of embodiments and claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term “and / or” as used herein means including one or more of the associated listed elements and all possible combinations thereof. Additionally, when used in this application, the terms “comprise” and its variations “comprises” and / or “comprising” refer to the presence of stated features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof. Without further limitation, an element defined by the phrase “comprising an…” does not exclude the presence of additional identical elements in the process, method, or apparatus that includes said element.

[0036] In this application, each embodiment focuses on describing the differences from other embodiments, and similar or identical parts between embodiments can be referred to mutually. For methods, products, etc., disclosed in the embodiments, if they correspond to the method section disclosed in the embodiments, then the relevant parts can be referred to the description of the method section.

[0037] To make the objectives, technical solutions, and advantages of this application clearer, the following description will be provided in conjunction with the accompanying drawings and specific embodiments.

[0038] Figure 1 This is a schematic diagram of the structure of a high-voltage control circuit for a new energy vehicle provided in an embodiment of this application, as shown below. Figure 1 As shown, it includes: a first pre-charge circuit (as shown in ① in the figure), a second pre-charge circuit (as shown in ② in the figure), a first capacitor C1, a second capacitor C2, a first microcontroller unit MCU1, and a second microcontroller unit MCU2. The first and second pre-charge circuits are shown as examples.

[0039] The input sides of both the first pre-charge circuit and the second pre-charge circuit are used to connect to the positive terminal of the power battery. The output side of the first pre-charge circuit is connected to the first capacitor C1 and the first microcontroller unit MCU1 in sequence. The output side of the second pre-charge circuit is connected to the second capacitor C2 and the second microcontroller unit MCU2 in sequence. The positive terminals of the first capacitor C1 and the second capacitor C2 are short-circuited.

[0040] The first pre-charge circuit and the second pre-charge circuit carry different loads. In order to ensure the stability of new energy vehicles during high-voltage power-on and power-off processes, the load types carried by the first pre-charge circuit and the second pre-charge circuit can be adjusted according to the load size.

[0041] Pre-charge circuit faults mainly include pre-charge circuit blockage or short circuit, and mechanical faults in the pre-charge contactor, such as a longer-than-expected pre-charge relay operating time or a pre-charge contactor failing to operate upon receiving a command. This application addresses this by setting up a first pre-charge circuit and a second pre-charge circuit, and short-circuiting the first capacitor C1 and the second capacitor C2 connected to the output terminals of the two pre-charge circuits. Thus, when either pre-charge circuit fails, the other pre-charge circuit charges the corresponding capacitors C1 and C2 of the first microcontroller unit MCU1 and the second microcontroller unit MCU2, ensuring the vehicle can still start smoothly. Although the pre-charge speed will decrease slightly during this process, other systems will continue to operate normally.

[0042] In this embodiment, a high-voltage control circuit for the new energy vehicle is formed by a first pre-charge circuit, a second pre-charge circuit, a first capacitor C1, a second capacitor C2, a first microcontroller unit MCU1, and a second microcontroller unit MCU2. The first and second pre-charge circuits carry different loads, and the first and second microcontroller units MCU1 and MCU2 control the different loads to ensure the stability of the new energy vehicle during high-voltage power-on and power-off processes. The output side of the first pre-charge circuit is sequentially connected to the first capacitor C1 and the first microcontroller unit MCU1, and the output side of the second pre-charge circuit is sequentially connected to the second capacitor C2 and the second microcontroller unit MCU2. The first capacitor C1 and the second capacitor C2 are short-circuited. When either pre-charge circuit fails, the other pre-charge circuit charges the capacitors C1 and C2 corresponding to the first and second microcontroller units MCU1 and MCU2, respectively, thereby ensuring that the controllers and loads corresponding to the two pre-charge circuits can work normally and ensuring the continuity of vehicle startup and operation.

[0043] In one possible implementation, such as Figure 1 As shown, the high-voltage control circuit for new energy vehicles also includes a first main positive contactor K1 and a second main positive contactor K3.

[0044] The first precharge circuit is connected in parallel with the first main positive contactor K1, and the second precharge circuit is connected in parallel with the second main positive contactor K3.

[0045] The input sides of the first main positive contactor K1 and the second main positive contactor K3 are both used to connect to the positive terminal of the power battery. The output side of the first main positive contactor K1 is connected to the first capacitor C1 and the first microcontroller unit MCU1 in sequence; the output side of the second main positive contactor K3 is connected to the second capacitor C2 and the second microcontroller unit MCU2 in sequence.

[0046] The first pre-charge circuit includes a contactor K2 and a resistor R1 connected in series; the second pre-charge circuit includes a contactor K4 and a resistor R2 connected in series; the input terminal of the contactor K2 is the input side of the first pre-charge circuit, and the input terminal of the contactor K4 is the input side of the second pre-charge circuit.

[0047] Figure 1 The image shows the positive contactor; the negative contactor is located inside the Battery Disconnect Unit (BDU).

[0048] In the actual control process, before the main contactor closes, the pre-charge circuit first closes the contactor connected in series with the resistor to pre-charge the capacitor, bringing its voltage close to the bus voltage. The main contactor is then closed only when the voltage difference across it approaches zero. This reduces the current surge at the moment of closure, effectively protecting the main contactor and its connected high-voltage electrical components. The first main positive contactor K1 serves as the main control switch for the load branch connected to the first pre-charge circuit, while the second main positive contactor K3 is responsible for the overall control of the load branch connected to the second pre-charge circuit.

[0049] Furthermore, when the load power connected to the first precharge circuit and the second precharge circuit is large, taking the connection of drive motors M1 and M2 as an example, the capacitance of the first capacitor C1 and the second capacitor C2 corresponding to the first microcontroller MCU1 and the second microcontroller MCU2 is large.

[0050] If the two drive motors operate under different conditions, such as M1 consuming high power and M2 generating high power, or the high switching frequency of the power transistors generating voltage pulses, a large instantaneous voltage difference may exist between the first capacitor C1 and the second capacitor C2. In this case, the two capacitors form a circuit through the first main positive contactor K1 and the second main positive contactor K3. Due to the voltage difference, current flows through this circuit, and the relatively small impedance leads to a relatively large ripple current. This significantly increases the heat generated by the first main positive contactor K1 and the second main positive contactor K3, thus affecting their service life. Therefore, when the two drive motors operate under drastically different conditions, the first capacitor C1 and the second capacitor C2 corresponding to the first microcontroller unit MCU1 and the second microcontroller unit MCU2 are short-circuited at the high-voltage positive terminal. This eliminates the voltage difference between the first capacitor C1 and the second capacitor C2, thereby eliminating the ripple current, improving the operating conditions of the first main positive contactor K1 and the second main positive contactor K3, effectively ensuring the stability of the high-voltage power-on / off circuit, and improving the reliability of the high-voltage control circuit.

[0051] In one possible implementation, both the first capacitor C1 and the second capacitor C2 are thin-film capacitors.

[0052] In this embodiment, when the load connected to the first microcontroller unit MCU1 or the second microcontroller unit MCU2 is a drive motor, the corresponding high-voltage control circuit of the new energy vehicle is equivalent to a motor controller. The film capacitor used in the motor controller can also be called a bus support capacitor. Film capacitors have excellent voltage and shock resistance capabilities, and play a role in stabilizing and filtering the voltage during drive motor operation. They absorb and release electrical energy, buffer, and prevent voltage spikes from impacting the vehicle's power battery and other high-voltage components, reducing voltage and current fluctuations. Especially during vehicle energy feedback, sudden voltage changes can be absorbed and stabilized through the temporary transient nature of the film capacitor. Specifically:

[0053] 1) Current Smoothing: In motor drive systems, the inverter converts the battery's DC power into a voltage with smaller fluctuations via a converter, and then converts it into a rectangular wave approximating AC power via IGBT switching elements. This generates large surge voltages, which need to be eliminated using smoothing capacitors. Thin-film capacitors can absorb and release energy, helping to stabilize voltage and current, reducing voltage and current fluctuations, thereby protecting the drive motor and the entire system from damage caused by surge voltages.

[0054] 2) Improve system stability: By smoothing the current, the thin film capacitor can ensure that the drive motor can obtain a stable power supply during startup and operation, reduce drive motor failures and performance degradation caused by voltage fluctuations, and ensure the reliable operation of the motor drive system.

[0055] The capacitors within the motor controller are relatively large; that is, when the load connected after the first microcontroller unit MCU1 or the second microcontroller unit MCU2 is a drive motor, the first capacitor C1 or the second capacitor C2 is relatively large. The charging speed is t = τ * Ln[(V1 - V0) / (V1 - Vt)], where τ is the time constant, V1 is the final charging voltage (bus voltage), V0 is the initial capacitor voltage (generally 0), and Vt is the voltage across the capacitor at time t. If V0 = 0 and Vt = 0, meaning the capacitor is directly charged from 0 to V1 (bus voltage), it is equivalent to directly charging the capacitor without using the "extended capacitor charging" circuit. In this case, t = τ * Ln1 = 0, and the charging current is ∞. This means the charging speed is extremely fast, and the charging current is extremely large. Therefore, when designing the high-voltage power-on circuit of the controller, it is necessary to consider extending the charging time of the capacitor and reducing the charging current. When the capacitor is almost fully charged, the main positive contactor is closed. At this time, the voltage difference between the two ends of the main positive contactor is small, and the current passing through it at the moment of closure is small, which can effectively protect the main positive contactor and other high-voltage electrical components.

[0056] Based on the foregoing embodiments, the first precharge circuit and the second precharge circuit can be configured in various ways in different embodiments.

[0057] In one possible implementation, the first pre-charge circuit includes a contactor K2 and a resistor R1 connected in series; the second pre-charge circuit includes a contactor K4 and a resistor R2 connected in series; the input terminals of contactors K2 and K4 are the input terminals of the first pre-charge circuit and the second pre-charge circuit, respectively.

[0058] Among them, resistor R1 is connected in series with contactor K2 and then in parallel with the first main positive contactor K1; resistor R2 is connected in series with contactor K4 and then in parallel with the second main positive contactor K3.

[0059] In another possible implementation, the high-voltage control circuit for new energy vehicles, the first pre-charge circuit also includes a diode D1 for backflash protection, connected in series between resistor R1 and contactor K2.

[0060] In another possible implementation, the second precharge circuit also includes a diode D2 for backflash protection, connected in series between resistor R2 and contactor K4.

[0061] In another possible implementation, such as Figure 2 As shown, the first precharge circuit also includes a diode D1 for anti-backlash protection, which is connected in series between resistor R1 and contactor K2; the second precharge circuit also includes a diode D2 for anti-backlash protection, which is connected in series between resistor R2 and contactor K4.

[0062] In this embodiment, the anti-backflash diode can effectively prevent current from flowing in the wrong direction, thereby avoiding potential damage to contactor K2, contactor K4, and the entire vehicle's power battery system.

[0063] In other possible implementations, such as Figure 3 The first pre-charge circuit of the high-voltage control circuit for new energy vehicles shown also includes a fuse F1, which is connected between the first microcontroller unit MCU1 and the first main positive contactor K1;

[0064] The second precharge circuit also includes a fuse F2, which is connected between the second microcontroller unit MCU2 and the second main positive contactor K3.

[0065] In this embodiment, fuses F1 and F2 can quickly cut off the circuit in the event of an abnormal increase in current or a short circuit, thus avoiding serious safety accidents.

[0066] In one possible implementation, such as Figure 4 The high-voltage control circuit for new energy vehicles shown has the output side of the first microcontroller unit MCU1 connected to the first drive motor M1, and the output side of the second microcontroller unit MCU2 connected to the second drive motor M2.

[0067] In this embodiment, drive motors M1 and M2 are high-power loads that undertake the task of vehicle operation. By connecting drive motors M1 and M2 to the first pre-charge circuit and the second pre-charge circuit respectively, it is possible to ensure that drive motors M1 and M2 can work independently. On the other hand, when drive motors M1 and M2 work simultaneously, the independent pre-charge circuit can improve the safety and stability of drive motor startup.

[0068] In one possible implementation, both the first precharge circuit and the second precharge circuit further include one or more precharge branches, the output side of which is connected to the branch load; each branch load is connected in parallel with the first microcontroller unit MCU1 or each branch load is connected in parallel with the second microcontroller unit MCU2.

[0069] In one possible implementation, both the first precharge circuit and the second precharge circuit further include branch fuses disposed on the precharge branch, the branch fuses being connected between the main positive contactor and the branch load; the main positive contactor includes a first main positive contactor K1 or a second main positive contactor K3, and the branch fuses correspond one-to-one with the branch loads.

[0070] In this embodiment, each fuse can quickly disconnect the circuit in the event of a fault in the corresponding load, an abnormal increase in current, or a short circuit, so as to prevent the impact on the safety of other loads and the high-voltage control circuit of new energy vehicles, thereby preventing the occurrence of serious safety accidents.

[0071] In one possible implementation, when the branch load is an electric heater PTC, a contactor is also provided on the pre-charge branch connected to the electric heater PTC, and the contactor is connected between the main positive contactor and the branch fuse.

[0072] In this embodiment, since the electric heater PTC is a heating device and lacks a dedicated controller, the power cannot be precisely controlled. Therefore, a corresponding contactor needs to be configured to control the operation of the electric heater PTC.

[0073] The specific specifications for the contactor are as follows: its maximum current carrying capacity must be no less than twice the maximum load current. This is to ensure that the contacts can smoothly handle larger currents, enhance overload capacity, and extend service life. Simultaneously, it effectively prevents arcing and sticking caused by the lack of a controller for the PTC heater, which could lead to the contactor performing closing and opening operations under load.

[0074] like Figure 5 The image shows a high-voltage control circuit for a new energy vehicle provided in another embodiment of this application. Figure 5In the illustrated embodiment, the high-voltage control circuit of the new energy vehicle is designed with two pre-charge circuits: Pre-charge circuit one carries three high-voltage loads: drive motor M1 (control module corresponds to the first microcontroller unit MCU1), air conditioner AC1 (for cab cooling and battery cooling), and electric heater PTC1 (for battery heating); pre-charge circuit two carries six high-voltage loads: drive motor M2 (control module corresponds to the second microcontroller unit MCU2), high-voltage steering motor M3 (control module corresponds to the electronic control steering system (EHPS)), high-voltage air pump motor M4 (control module corresponds to Advanced Process Control (APC)), high-voltage to low-voltage DC-DC converter, air conditioner AC2 (for battery cooling), and electric heater PTC2 (for cab heating). Except for drive motors M1 and M2, the other loads are considered small loads.

[0075] Figure 5 In the diagram, T0 to T5 are sampling points, I1 and I2 are sampling currents, and U2 and U3 are sampling voltages. F1 to F9 are fuses. Corresponding to electric heaters PTC 1 and PCT 2, contactors K5 and K6 are installed. During power-on control, contactors K2 and K4 close first. When the voltage values ​​at point T2 are close to those at point T1, the first pre-charge circuit completes pre-charging. When the voltage values ​​at point T3 are close to those at point T1, the second pre-charge circuit completes pre-charging. After pre-charging is complete, the first main positive contactor K1 and the second main positive contactor K3 close.

[0076] During the power-down control process, it is determined whether the current values ​​collected at points T2 and T3 are less than the set current value. If they are less than the set current value, the first main positive contactor K1 and the second main positive contactor K3 are disconnected to complete the power-down, avoiding contact arcing or sticking caused by power-down under load. Additionally, if a vehicle control unit (VCO) is received... , If the current values ​​collected at T2 and T3 are greater than the set current value within 30 seconds after the VCU sends the power-down command, the corresponding main positive contactor will be disconnected to prevent abnormal control at the load end from affecting the power-down.

[0077] Figure 6 and Figure 7 The direction of current flow is shown when the first precharge circuit and the second precharge circuit fail, respectively.

[0078] like Figure 6As shown, in the event of a failure in the first pre-charge circuit, the second pre-charge circuit can be used as an emergency circuit to charge the entire vehicle. Specifically, the current passes through the second main positive contactor K3, and is distributed to the loads of each branch of the second pre-charge circuit at position T3, and then passes through the short-circuited film capacitor at point B. Figure 6 (Not shown) The power battery energy is distributed to the load of the first pre-charge circuit. Additionally, at position T3, the total current I2 of the second pre-charge circuit is detected by current sensor AT2 to ensure that the current of the second pre-charge circuit does not exceed a preset limit. If the current exceeds the threshold, the power output of the first microcontroller unit MCU1 and the second microcontroller unit MCU2 is limited to the large load. Therefore, even if the first main positive contactor K1 of the first pre-charge circuit fails, the first pre-charge circuit can still operate in emergency mode, thus ensuring both emergency control functionality and circuit protection.

[0079] like Figure 7 As shown, when the second pre-charge circuit fails, the first pre-charge circuit can be used as an emergency circuit to charge the entire vehicle. Similarly, specifically, the current passes through the first main positive contactor K1, and is distributed to the loads of each branch of the first pre-charge circuit at position T2, and passes through the short-circuited film capacitor at point A. Figure 7 (Not shown) The power battery energy is distributed to the load of the second pre-charge circuit. Additionally, at position T2, the total current I1 of the first pre-charge circuit is detected by current sensor AT1 to ensure that the current of the first pre-charge circuit does not exceed a preset limit. If the current exceeds the threshold, the power output of the first microcontroller unit MCU1 and the second microcontroller unit MCU2 is limited to the high load. Therefore, even if the second main positive contactor K3 of the second pre-charge circuit fails, the second pre-charge circuit can still operate in emergency mode.

[0080] This application embodiment also provides a vehicle, which includes the aforementioned new energy vehicle high voltage control circuit, power battery and drive motor, the drive motor including a first drive motor M1 and a second drive motor M2;

[0081] In new energy vehicles, the high-voltage control circuit is connected between the power battery and the drive motor.

[0082] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A high-voltage control circuit for new energy vehicles, characterized in that, include: First pre-charge circuit, second pre-charge circuit, first capacitor C1, second capacitor C2, first microcontroller unit MCU1, and second microcontroller unit MCU2; The input sides of both the first pre-charge circuit and the second pre-charge circuit are used to connect to the positive terminal of the power battery. The output side of the first pre-charge circuit is connected to the first capacitor C1 and the first microcontroller unit MCU1 in sequence. The output side of the second pre-charge circuit is connected to the second capacitor C2 and the second microcontroller unit MCU2 in sequence. The positive terminals of the first capacitor C1 and the second capacitor C2 are short-circuited.

2. The high-voltage control circuit for new energy vehicles according to claim 1, characterized in that, It also includes the first main positive contactor K1 and the second main positive contactor K3; The first pre-charge circuit is connected in parallel with the first main positive contactor K1, and the second pre-charge circuit is connected in parallel with the second main positive contactor K3; The input sides of the first main positive contactor K1 and the second main positive contactor K3 are both used to connect to the positive terminal of the power battery, and the output side of the first main positive contactor K1 is connected to the first capacitor C1 and the first microcontroller unit MCU1 in sequence. The output side of the second main positive contactor K3 is connected in sequence to the second capacitor C2 and the second microcontroller unit MCU2; The first pre-charge circuit includes a contactor K2 and a resistor R1 connected in series; the second pre-charge circuit includes a contactor K4 and a resistor R2 connected in series; the input terminal of the contactor K2 is the input side of the first pre-charge circuit, and the input terminal of the contactor K4 is the input side of the second pre-charge circuit.

3. The high-voltage control circuit for new energy vehicles according to claim 2, characterized in that, The first precharge circuit also includes a diode D1 for backflash protection, connected in series between the resistor R1 and the contactor K2; the second precharge circuit also includes a diode D2 for backflash protection, connected in series between the resistor R2 and the contactor K4.

4. The high-voltage control circuit for new energy vehicles according to claim 2, characterized in that, The first precharge circuit also includes a fuse F1, which is connected between the first microcontroller unit MCU1 and the first main positive contactor K1; The second precharge circuit also includes a fuse F2, which is connected between the second microcontroller unit MCU2 and the second main positive contactor K3.

5. The high-voltage control circuit for new energy vehicles according to claim 1, characterized in that, Both the first capacitor C1 and the second capacitor C2 are thin-film capacitors.

6. The high-voltage control circuit for new energy vehicles according to claim 1, characterized in that, The output side of the first microcontroller unit MCU1 is connected to the first drive motor M1; the output side of the second microcontroller unit MCU2 is connected to the second drive motor M2.

7. The high-voltage control circuit for new energy vehicles according to claim 2, characterized in that, Both the first precharge circuit and the second precharge circuit further include one or more precharge branches, the output side of which is connected to the branch load; each branch load is connected in parallel with the first microcontroller unit MCU1 or each branch load is connected in parallel with the second microcontroller unit MCU2.

8. The high-voltage control circuit for new energy vehicles according to claim 7, characterized in that, Both the first pre-charge circuit and the second pre-charge circuit further include a branch fuse disposed on the pre-charge branch, the branch fuse being connected between the main positive contactor and the branch load; the main positive contactor includes a first main positive contactor K1 or a second main positive contactor K3, and the branch fuse corresponds one-to-one with the branch load.

9. The high-voltage control circuit for new energy vehicles according to claim 8, characterized in that, When the branch load is an electric heater PTC, a contactor is also provided on the pre-charge branch connected to the electric heater PTC. The contactor is connected between the main positive contactor and the branch fuse.

10. A vehicle comprising a new energy vehicle high-voltage control circuit, a power battery, and a drive motor as described in any one of claims 1 to 9, wherein the drive motor comprises a first drive motor M1 and a second drive motor M2; in, The high-voltage control circuit of the new energy vehicle is connected between the power battery and the drive motor.

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