Low-power-consumption anti-sparking power supply system and electric vehicle

Abstract

The utility model provides a low power consumption anti-sparking power supply system and an electric vehicle, comprising: a main discharge loop connected with a battery and a load, the battery supplying power to the load when the main discharge loop is in a switch-on state; the pre-discharge circuit is connected with the main discharge loop, and when the main discharge loop is in a disconnected state, the pre-discharge circuit supplies power to the load; the interruption circuit is connected with the pre-amplification circuit and is used for sending out an interruption signal according to the current condition of the pre-amplification circuit; and the control circuit is connected with the interruption circuit, the battery management system is dormant when the battery leaves the vehicle, and the control circuit responds to the interruption signal to wake up the battery management system and control the main discharge loop to be switched on. According to the utility model, the anti-sparking function can be realized, and the battery management system can enter a dormancy state during the off-vehicle charging period of the battery, so that the power consumption is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of electric vehicles, in particular to a low-power consumption anti-ignition power supply system and an electric vehicle. Background Art

[0002] At present, electric vehicles such as electric bicycles, electric cars and electric two-wheelers are developing faster and faster, and their market share is getting higher and higher. In particular, the development of battery-swap two-wheelers is particularly rapid. In the application scenario of battery swapping, when the battery pack is charged, it is removed from the charging cabinet and inserted into the vehicle. Due to the large capacitance of the load on the vehicle, if the main discharge circuit is in the on state at this time, sparks will occur. Over time, it will cause poor contact of the discharge interface, and even fire in severe cases.

[0003] The existing technology detects the discharge current. As long as the discharge current is less than the set value, the main discharge circuit is cut off and the pre-discharge circuit is turned on. The pre-discharge circuit supplies power to the external load to avoid sparking caused by the main discharge circuit being turned on when the fully charged battery pack is plugged into the vehicle.

[0004] However, in the prior art, the battery management system is required to collect the current on the main discharge circuit in real time, and the battery management system is always in working state, which consumes a lot of power. Utility Model Content

[0005] In view of this, the purpose of the utility model is to provide a low-power anti-sparking power supply system and an electric vehicle, which can avoid the anti-sparking phenomenon while putting the battery management system into sleep mode to reduce power consumption.

[0006] To achieve the above-mentioned purpose, the utility model provides a low-power consumption anti-sparking power supply system, which is applied to the battery management system of an electric vehicle, including: a main discharge circuit, connected to a battery and a load, and when the main discharge circuit is connected, the battery supplies power to the load; a pre-discharge circuit, connected to the main discharge circuit, and when the main discharge circuit is disconnected, the pre-discharge circuit supplies power to the load; an interrupt circuit, connected to the pre-discharge circuit, and sending an interrupt signal according to the current condition of the pre-discharge circuit; a control circuit, connected to the interrupt circuit, and the battery management system is dormant when the battery leaves the vehicle, and the control circuit wakes up the battery management system in response to the interrupt signal and controls the main discharge circuit to be connected.

[0007] Preferably, the control circuit includes a control unit, an interrupt detection pin of the control unit is connected to the interrupt circuit, the battery management system is dormant before the interrupt signal is triggered, and the battery management system is awakened after the interrupt signal is triggered.

[0008] Preferably, the main discharge circuit comprises a discharge switch and a sampling resistor, and the battery, the load, the discharge switch and the sampling resistor are connected in series in sequence.

[0009] Preferably, the pre-discharge circuit comprises a pre-discharge switch and a pre-discharge resistor, the pre-discharge switch and the pre-discharge resistor are connected in series, and the pre-discharge circuit is connected in parallel with the discharge switch.

[0010] Preferably, the interrupt circuit includes a transistor, a first resistor and a second resistor, the emitter of the transistor is connected to the pre-discharge circuit, the base of the transistor is connected to the first end of the first resistor, the collector of the transistor is connected to the first end of the second resistor and a control unit, the second end of the first resistor is connected to the pre-discharge switch and the pre-discharge resistor, and the second end of the second resistor is connected to a power supply.

[0011] Preferably, the control circuit connects the discharge switch and the pre-discharge switch, and when the current of the sampling resistor is less than a preset current threshold, the control circuit controls the discharge switch to be disconnected and the pre-discharge switch to be turned on, and the battery management system enters a dormant state.

[0012] Preferably, when the voltage drop generated on the second resistor reaches a set voltage drop value, the interrupt circuit generates the interrupt signal, the battery management system starts in response to the interrupt signal, and controls the discharge switch to be turned on through the control circuit.

[0013] Preferably, the control circuit includes an analog front-end chip, the analog front-end chip is connected to the discharge switch and the pre-release switch, the analog front-end chip collects the current of the sampling resistor, and the control unit controls the on and off of the release switch and the pre-release switch through the analog front-end chip.

[0014] Preferably, the discharge switch and the pre-discharge switch are MOS transistors, and the transistor is an NPN transistor.

[0015] The utility model also provides an electric vehicle, comprising the low-power consumption anti-spark power supply system as described in any one of the above items.

[0016] Compared with the prior art, the utility model has the following technical effects: the low-power anti-sparking power supply system provided by the utility model enables the battery to supply power to the load through the main discharge circuit, and supplies power to the load through the pre-discharge circuit when the main discharge circuit is disconnected, thereby avoiding sparking. The control circuit then controls the battery management system to sleep, without the need to detect the circuit current in real time, thereby reducing power consumption. According to the interrupt signal sent by the interrupt circuit, the control circuit wakes up the battery management system and controls the main discharge circuit to be connected. The control circuit uses the interrupt detection pin of its own MCU to receive the interrupt signal and wake up the dormant battery management system, without the need to add other control devices, thereby reducing costs.

[0017] The utility model can realize the function of preventing ignition and enable the battery management system to enter dormancy during the period when the battery is charged away from the vehicle, thereby reducing power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of a low-power anti-spark power supply system provided by an embodiment of the utility model;

[0019] Figure 2 A circuit diagram of an anti-spark power supply system for an electric vehicle provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0020] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, but the present invention is not limited to these embodiments. The present invention covers any substitution, modification, equivalent method and scheme made within the spirit and scope of the present invention.

[0021] In order to enable the public to have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, and those skilled in the art can fully understand the present invention without these detailed descriptions.

[0022] The present invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. It should be noted that the accompanying drawings are all simplified and use non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0023] Please refer to Figure 1 , is a schematic diagram of a low-power anti-spark power supply system provided in an embodiment of the utility model. Electric vehicles include electric bicycles, electric two-wheeled vehicles, electric vehicles, and electric scooters. The anti-spark power supply system provided in this embodiment is applied to an electric two-wheeled vehicle as an example. When the electric two-wheeled vehicle is running, the battery supplies power to the load. In order to avoid overcharging and over-discharging of the battery, the electric two-wheeled vehicle is also equipped with a battery management system (BMS) to monitor and manage the battery. The battery management system (BMS) includes an anti-spark power supply system, such as Figure 1As shown, the anti-sparking power supply system includes a main discharge circuit, a pre-discharge circuit, an interrupt circuit and a control circuit. The main discharge circuit is used to connect with the battery and the load. When the battery is inserted into the two-wheeled vehicle, it is connected to the main discharge circuit. After the main discharge circuit is connected, the battery supplies power to the load. When the battery needs to be charged, it is removed from the two-wheeled vehicle, the main discharge circuit is disconnected, and the battery management system is dormant; the pre-discharge circuit is connected to the main discharge circuit and the load. When the main discharge circuit is disconnected, the pre-discharge circuit is connected to supply power to the load; the interrupt circuit is connected to the pre-discharge circuit, and an interrupt signal is generated according to the current of the pre-discharge circuit and sent to the control circuit. The control circuit is connected to the interrupt circuit, and responds to the interrupt signal to wake up the dormant battery management system and control the main discharge circuit to be connected. In this embodiment, the main discharge circuit and the pre-discharge circuit are both connected to the control circuit, and the control circuit is used to connect and disconnect. When the battery is charged away from the vehicle, the main discharge circuit is disconnected and the pre-discharge circuit is connected to avoid sparking when the battery is fully charged and inserted into the two-wheeled vehicle. The BMS also enters a dormant state and no longer samples the circuit current to reduce power consumption. After the battery is fully charged and plugged into the two-wheeled vehicle, the battery supplies power to the load through the pre-discharge circuit, and the interrupt circuit generates an interrupt signal according to the current of the pre-discharge circuit and sends it to the control circuit, thereby waking up the BMS in the dormant state, and controlling the main discharge circuit to be connected through the control circuit, so that the battery supplies power to the load through the main discharge circuit. Therefore, the utility model can realize the anti-ignition function while also putting the BMS into dormancy, without the need for the BMS to detect current in real time, thereby reducing power consumption.

[0024] Specifically, the control circuit includes a control unit (MCU), and the MCU has an interrupt detection pin, which is connected to the interrupt circuit through the interrupt detection pin, receives the interrupt signal sent by the interrupt circuit, thereby interrupting the sleep of the BMS and waking it up. Before the control circuit receives the interrupt signal, the BMS is in a sleep state, and after the interrupt signal is triggered, the BMS is awakened. In this embodiment, the control unit also includes an analog front-end chip (AFE), and the AFE is used to collect battery information and the current on the main discharge circuit. Before the interrupt signal is triggered, the MCU and the AFE enter sleep and no longer work, thereby reducing power consumption. After the interrupt signal is triggered, the MCU and the AFE are started, and the MCU controls the main discharge circuit to be connected through the AFE, and the AFE continues to collect battery information and the current on the main discharge circuit. The embodiment of the utility model realizes the sleep and wake-up of the BMS by utilizing the pins of the MCU itself, without adding additional control equipment, thereby reducing costs.

[0025] Specifically, the main discharge circuit includes a discharge switch and a sampling resistor Rs. The battery, the load, the discharge switch and the sampling resistor Rs are connected in series in sequence to form a circuit for the battery to supply power to the load, wherein the discharge switch is used to realize the connection or disconnection of the main discharge circuit, the discharge switch is connected to the AFE, and the MCU controls the discharge switch on and off by controlling the AFE. The pre-discharge circuit includes a pre-discharge resistor Rp and a pre-discharge switch. When the main discharge circuit is disconnected, the pre-discharge resistor Rp supplies power to the load, wherein the pre-discharge switch is used to realize the connection or disconnection of the pre-discharge circuit, the pre-discharge switch is connected to the AFE, and the MCU controls the pre-discharge switch on and off by controlling the AFE.

[0026] Please refer to Figure 2 , is a circuit diagram of a low-power anti-sparking power supply system provided by an embodiment of the utility model. Among them, the main discharge circuit includes a sampling resistor Rs and a MOS tube Q1 as a discharge switch, the first end of the sampling resistor Rs is connected to the negative electrode of the battery BAT, the second end of the sampling resistor Rs is connected to the source of the MOS tube Q1, the drain of the MOS tube Q1 is connected to one end of the load, the other end of the load is connected to the positive electrode of the battery BAT, and the control end of the MOS tube Q1 is connected to the AFE; the pre-discharge circuit is connected in parallel with the MOS tube Q1, which includes a pre-discharge resistor Rp and a MOS tube Q2 as a pre-discharge switch, the first end of the pre-discharge resistor Rp is connected to the connection node of the sampling resistor Rs and the MOS tube Q1, the second end of the pre-discharge resistor Rp is connected to the source of the MOS tube Q2, the drain of the MOS tube Q2 is connected to the drain of Q1 and one end of the load, and the control end of the MOS tube Q2 is connected to the AFE. The interrupt circuit includes an NPN transistor Q3, a first resistor R1 and a second resistor R2, the emitter of the transistor Q3 is connected to the first end of the pre-discharge resistor Rp, the collector of the transistor Q3 is connected to the first end of the second resistor R2, the second end of R2 is connected to the power supply Vcc, the base of the transistor Q3 is connected to the first end of the first resistor R1, the second end of R1 is connected to the connection node of the pre-discharge resistor Rp and the MOS tube Q2, and the node between the transistor Q3 and the second resistor R2 is connected to the interrupt detection pin of the MCU.

[0027] In this embodiment, a current threshold can be preset. When the current on the main discharge circuit is less than the current threshold, it is considered that the battery is off-vehicle for charging, and the BMS can be dormant. When the battery is removed from the vehicle for charging, the current in the main discharge circuit will become smaller. The AFE in the control unit detects the current of the sampling resistor Rs and sends it to the MCU. The MCU compares it. When the detected current is less than the preset current threshold, the MCU controls the MOS tube Q1 to be disconnected through the AFE, and controls the MOS tube Q2 to be closed, so that the load is powered by the pre-discharge resistor Rp. After that, the MCU and AFE enter the dormant state to reduce power consumption. At this time, the triggering condition of the interrupt signal is also not met. When the battery is fully charged and plugged into the car, since the MOS tube Q1 is disconnected, there will be no ignition phenomenon. At this time, the battery BAT supplies power to the load through the pre-discharge circuit, and the current in the pre-discharge circuit increases. The current I1 flowing through the pre-discharge resistor Rp and the base current I2 flowing through the transistor Q3 will also increase; the base current I2 of the transistor Q3 increases, resulting in an increase in the collector current I3 of the transistor Q3; the collector current I3 of the transistor Q3 will produce a voltage drop on the second resistor R2. When the voltage drop reaches the set voltage drop value, the MCU interrupt signal can be triggered. The interrupt signal wakes up the BMS from the sleep state, and the MCU and AFE start, controlling the MOS tube Q1 to close and conduct, so that the battery BAT supplies power to the load through the main discharge circuit. Among them, the voltage drop value can be set according to the size of the first resistor R1 and the second resistor R2.

[0028] The utility model also provides an electric vehicle, which includes a battery management system, and the battery management system includes the low-power consumption anti-ignition power supply system provided by the above embodiment.

[0029] The low-power anti-sparking power supply system and electric vehicle provided by the embodiment of the utility model, when the current of the main discharge circuit is less than the preset current threshold, it is regarded as the battery is charged away from the vehicle, and the BMS can sleep, then the discharge switch is controlled to be disconnected, the main discharge circuit is cut off, and the pre-discharge circuit is connected to prevent sparking, and the BMS is set to enter a sleep state to reduce power consumption. After the battery is charged and inserted into the vehicle, the current of the pre-discharge circuit increases, and then the interrupt circuit triggers an interrupt signal to the MCU, awakening the dormant BMS, and then controlling the discharge switch to close, so that the main discharge circuit is connected, and the battery supplies power to the load. Therefore, the anti-sparking function can be realized without the need for real-time detection by the BMS, and the BMS can enter a sleep state when the battery is charged away from the vehicle, reducing power consumption.

[0030] Although the embodiments are described and illustrated separately above, some common technologies are involved. It is the opinion of ordinary technicians in this field that the embodiments can be replaced and integrated. If the content is not clearly recorded in one of the embodiments, reference can be made to another recorded embodiment.

[0031] The above-described implementation methods do not constitute a limitation on the protection scope of the technical solution. Any modification, equivalent replacement and improvement made within the spirit and principle of the above-described implementation methods shall be included in the protection scope of the technical solution.

Claims

1. A low-power anti-spark power supply system, applied to the battery management system of electric vehicles, characterized in that: include: A main discharge circuit is connected to the battery and the load, and when the main discharge circuit is connected, the battery supplies power to the load; A pre-discharge circuit connected to the main discharge circuit, when the main discharge circuit is disconnected, the pre-discharge circuit supplies power to the load; An interrupt circuit, connected to the preamplifier circuit, and sending an interrupt signal according to the current condition of the preamplifier circuit; The control circuit is connected to the interrupt circuit. The battery management system is dormant when the battery is away from the vehicle. The control circuit wakes up the battery management system in response to the interrupt signal and controls the main discharge circuit to be turned on.

2. The low-power anti-spark power supply system according to claim 1, characterized in that: The control circuit includes a control unit, an interrupt detection pin of the control unit is connected to the interrupt circuit, before the interrupt signal is triggered, the battery management system is dormant, and after the interrupt signal is triggered, the battery management system is awakened.

3. The low-power anti-spark power supply system according to claim 2, characterized in that: The main discharge circuit includes a discharge switch and a sampling resistor, and the battery, the load, the discharge switch and the sampling resistor are connected in series in sequence.

4. The low-power anti-spark power supply system according to claim 3, characterized in that: The pre-discharge circuit comprises a pre-discharge switch and a pre-discharge resistor, wherein the pre-discharge switch and the pre-discharge resistor are connected in series, and the pre-discharge circuit is connected in parallel with the discharge switch.

5. The low-power anti-spark power supply system according to claim 4, characterized in that: The interrupt circuit includes a transistor, a first resistor and a second resistor, the emitter of the transistor is connected to the pre-discharge circuit, the base of the transistor is connected to the first end of the first resistor, the collector of the transistor is connected to the first end of the second resistor and a control unit, the second end of the first resistor is connected to the pre-discharge switch and the pre-discharge resistor, and the second end of the second resistor is connected to a power supply.

6. The low-power anti-spark power supply system according to claim 5, characterized in that: The control circuit connects the discharge switch and the pre-discharge switch. When the current of the sampling resistor is less than a preset current threshold, the control circuit controls the discharge switch to be disconnected and the pre-discharge switch to be turned on, and the battery management system enters a dormant state.

7. The low-power anti-spark power supply system according to claim 6, characterized in that: When the voltage drop generated on the second resistor reaches a set voltage drop value, the interrupt circuit generates the interrupt signal, the battery management system starts in response to the interrupt signal, and controls the discharge switch to be turned on through the control circuit.

8. The low-power anti-spark power supply system according to claim 7, characterized in that: The control circuit includes an analog front-end chip, the analog front-end chip is connected to the discharge switch and the pre-discharge switch, the analog front-end chip collects the current of the sampling resistor, and the control unit controls the on and off of the discharge switch and the pre-discharge switch through the analog front-end chip.

9. The low-power anti-spark power supply system according to claim 5, characterized in that: The discharge switch and the pre-discharge switch are MOS transistors, and the transistor is an NPN transistor.

10. An electric vehicle, characterized in that: It comprises a low-power consumption anti-spark power supply system as described in any one of claims 1 to 9.

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