An electrical safety protection circuit and protection system for electric vehicles

Abstract

The present invention provides an electrical safety protection circuit and protection system for electric vehicles, including a power module, a protection module and a load; the protection module is connected in series to the negative line of the main circuit, with one end connected to the negative electrode of the battery and the other end connected to the negative electrode of the load; an electric door lock is also provided between the positive electrode of the battery and the load, and the electric door lock is connected to the load via a rear lock line; and an anti-backflow diode D1 is also included, the anode of D1 is connected to the rear lock line via a voltage acquisition line, and the cathode is connected to the protection module. The electrical safety protection circuit and protection system for electric vehicles described in the present invention are safe to park. When the electric door lock line is closed, the module limits the current to 100mA, quickly cuts off the power after overcurrent, has a fast response speed, a small limit value, is not prone to sparks, and has high safety; when the electric door lock is opened, the module supplies power to the rear through a MOS tube, has a strong overcurrent capacity, meets the normal working current, and has a short-circuit protection function, and has a higher response speed than traditional methods.

Description

Technical Field

[0001] The present invention belongs to the field of electric vehicle safety protection systems, and in particular relates to an electrical safety protection circuit and a protection system for electric vehicles. Background Art

[0002] With the improvement of people's living standards, electric vehicles have gradually replaced bicycles and integrated into the lives of grassroots people. At the same time, they have also brought safety hazards. Due to uneven usage and storage conditions, as well as improper operation by users, electric vehicles often catch fire, posing a threat to the safety of people's lives and property. The main reason is the aging of lines and devices, which causes fires caused by electrical short circuits. There is an urgent need for a protection system against overcurrent and short circuits to prevent fires. Summary of the Invention

[0003] In view of this, the present invention aims to provide an electrical safety protection circuit and protection system for electric vehicles to solve the shortcomings of the above problems.

[0004] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0005] An electrical safety protection circuit and protection system for electric vehicles, including a power module, a protection module and a load;

[0006] The protection module is connected in series to the negative line of the main circuit, with one end connected to the negative electrode of the battery and the other end connected to the negative electrode of the load;

[0007] There is also an electric door lock between the positive pole of the battery and the load, and the electric door lock is connected to the load through the rear lock line;

[0008] It also includes an anti-backflow diode D1, the anode of D1 is connected to the lock line through the voltage acquisition line, and the cathode is connected to the protection module.

[0009] Furthermore, the protection module includes a current limiting resistor R3, a voltage dividing resistor R1, a voltage dividing resistor R2, a voltage regulator tube Z1, an NPN transistor Q1, a power NMOS tube T1 and a recoverable resistor RT;

[0010] The cathode end of the anti-backflow diode D1 is connected to the voltage divider resistor R1;

[0011] The base of Q1 is connected to the negative pole of the load through R3, the emitter of Q1 is connected to the negative pole of the power supply, and the collector of Q1 is connected to R1;

[0012] R2 is connected to Z1 in parallel, with one end of R2 connected to R1 and the other end connected to the negative pole of the power supply; the cathode of Z1 is connected to R1, and the anode is connected to the negative pole of the power supply;

[0013] T1 and RT are set in parallel, one end of RT is connected to the negative pole of the power supply, and the other end is connected to the load; the G pole of T1 is connected to the resistor R1, the S pole is connected to the negative pole of the power supply, and the D pole is connected to the load.

[0014] Furthermore, it includes a protection module, a battery, a controller, an alarm and a load, and the controller, alarm and load are connected in parallel; one end of the protection module is connected to the negative pole of the battery, and the other end is connected to the negative pole of the controller, alarm and load; the positive pole of the controller, alarm and load is connected to the positive pole of the battery.

[0015] Compared with the prior art, the electrical safety protection circuit and protection system for electric vehicles described in the present invention have the following advantages:

[0016] (1) The electrical safety protection circuit and protection system for electric vehicles described in the present invention are safe to park. When the electric door lock line is closed, the maximum current limit of the module is controlled at 100mA, and the power is quickly cut off after overcurrent. It has a fast response speed, a small limit value, is not easy to generate sparks, and has high safety.

[0017] (2) The electrical safety protection circuit and protection system for electric vehicles described in the present invention ensure driving safety. When the electric door lock is turned on, the module supplies power to the rear through the MOS tube. It has a strong overcurrent capacity, meets the normal operating current, and has a short-circuit protection function. The response speed is higher than the traditional method;

[0018] (3) The electrical safety protection circuit and protection system for electric vehicles described in the present invention ensure charging safety. When the vehicle is charging, it does not affect the operation of the fire protection module and continuously provides current limiting protection. Even if a short circuit problem occurs at the rear, it can still provide normal protection.

[0019] (4) The electrical safety protection circuit and protection system for electric vehicles described in the present invention can automatically recover after a short circuit is released, without the need to replace components, thus reducing maintenance costs and facilitating use;

[0020] (5) The electrical safety protection circuit and protection system for electric vehicles described in the present invention prevent sparks from being generated when the vehicle is connected to the battery due to current limitation, thereby protecting the terminals and improving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0022] Figure 1 This is a schematic diagram of the protection method principle according to an embodiment of the present invention;

[0023] Figure 2This is a schematic diagram of the circuit principle of the protection system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0026] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0027] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0028] like Figure 1 and Figure 2 As shown, an electrical safety protection circuit and protection system for electric vehicles include a power module, a protection module and a load;

[0029] The protection module is connected in series to the negative line of the main circuit, with one end connected to the negative electrode of the battery and the other end connected to the negative electrode of the load;

[0030] There is also an electric door lock between the positive pole of the battery and the load, and the electric door lock is connected to the load through the rear lock line;

[0031] It also includes an anti-backflow diode D1, the anode of D1 is connected to the lock line through the voltage acquisition line, and the cathode is connected to the protection module.

[0032] The protection module includes a current limiting resistor R3, a voltage dividing resistor R1, a voltage dividing resistor R2, a voltage regulator tube Z1, an NPN transistor Q1, a power NMOS tube T1 and a recoverable resistor RT;

[0033] The cathode end of the anti-backflow diode D1 is connected to the voltage divider resistor R1;

[0034] The base of Q1 is connected to the negative pole of the load through R3, the emitter of Q1 is connected to the negative pole of the power supply, and the collector of Q1 is connected to R1;

[0035] R2 is connected to Z1 in parallel, with one end of R2 connected to R1 and the other end connected to the negative pole of the power supply; the cathode of Z1 is connected to R1, and the anode is connected to the negative pole of the power supply;

[0036] T1 and RT are set in parallel, one end of RT is connected to the negative pole of the power supply, and the other end is connected to the load; the G pole of T1 is connected to the resistor R1, the S pole is connected to the negative pole of the power supply, and the D pole is connected to the load.

[0037] An electrical safety protection system for an electric vehicle comprises a protection module, a battery, a controller, an alarm and a load, wherein the controller, the alarm and the load are connected in parallel;

[0038] One end of the protection module is connected to the negative pole of the battery, and the other end is connected to the negative pole of the controller, alarm, and load;

[0039] The positive poles of the controller, alarm and load are connected to the positive pole of the battery.

[0040] The principle during specific use is as follows: the protection system is connected in series to the negative line of the main circuit, one end is connected to the negative electrode of the battery B-, and the other end is connected to the negative electrode of the load (controller, anti-theft device, instrument light, etc.), and a voltage collection line is taken from the rear line of the lock and connected to D1.

[0041] State 1: The power door is locked and the immobilizer is powered off, and the vehicle is not charging. The rear lock line has zero voltage. The base of Q1 is connected to the negative terminal of the load through R3, resulting in a zero voltage and a cutoff state. The rear lock line is connected to the voltage divider resistor R1 through the anti-reverse diode D1. At this point, there is no voltage across R1 and R2, and the gate voltage of T1 is zero, indicating the vehicle is off. Current can only flow from the negative terminal of the load to B- through RT.

[0042] If a short circuit occurs at this point, a current exceeding 100mA will flow through RT, causing it to rapidly heat up and its resistance to increase dramatically, limiting the current to 10-20mA and providing overcurrent protection. Simultaneously, the voltage across the terminals increases, raising the voltage at the negative terminal of the load. This, through R3, raises the base voltage of Q1, turning it on and keeping the gate voltage of T1 low, keeping T1 permanently off. At this point, even if the ignition is unlocked, T1 will not turn on. Once the short circuit is resolved and the current returns to normal, RT will cool within tens of seconds, returning to its normal resistance and releasing the system protection.

[0043] State 2: The electric door lock or immobilizer is powered on, and the vehicle is in use. The base of Q1 is connected to the negative terminal of the load via R3, resulting in a voltage of 0 and a cutoff state. The battery voltage is connected to the voltage divider resistors R1R2 via D1. Due to the parallel Zener diode across R2, the voltage across R2 is at the regulated voltage VD1, which is greater than the turn-on voltage of T1, turning T1 on. T1 can pass a large current, meeting normal power requirements.

[0044] At this point, a short circuit occurs, equivalent to connecting the negative terminal of the load to B+. The voltage on R3 increases, raising the base voltage on Q1, turning it on. This pulls down the gate voltage on T1, shutting it off. Current then flows through RT, returning to the same state as in state 1, triggering the protection mechanism. Because the back-of-the-lock wire is still powered, Q1 remains on, and the gate voltage on T1 continues to be pulled down, keeping it in the off state. The door lock must be turned off to allow RT to cool and recover, allowing the system to release protection.

[0045] State 3: The vehicle is charging. The charging circuit does not pass through the protection system, so there is no impact on the system and the protection function is functioning normally. It is important to note that spontaneous combustion of electric vehicles often occurs during the charging state. This is due to unstable charger output and spikes, which impact electrical components such as controllers, causing breakdown and short circuits, leading to spontaneous combustion. Regardless of whether the key is on or off, the protection system provides short-circuit protection for rear electrical components (such as controllers).

[0046] In addition, when the vehicle is connected to the battery, due to the capacitance of the rear load, the instantaneous current is large and may cause sparks. This system can limit the current to around 100mA, preventing sparks, improving installation safety, and protecting the connection contacts.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An electrical safety protection circuit for an electric vehicle, characterized in that: Including power module, protection module and load; The protection module is connected in series to the negative line of the main circuit, with one end connected to the negative pole of the battery and the other end connected to the negative pole of the load. A voltage collection line is taken from the rear line of the lock and connected to the anti-backflow diode D1; There is also an electric door lock between the positive pole of the battery and the load, and the electric door lock is connected to the load through the rear lock line; The anode of the anti-backflow diode D1 is connected to the lock line through the voltage acquisition line, and the cathode is connected to the protection module; The protection module includes a current limiting resistor R3, a voltage dividing resistor R1, a voltage dividing resistor R2, a voltage regulator tube Z1, an NPN transistor Q1, a power NMOS tube T1 and a recoverable resistor RT; The cathode end of the anti-backflow diode D1 is connected to the voltage divider resistor R1; The base of the NPN transistor Q1 is connected to the negative electrode of the load through R3, the emitter of the NPN transistor Q1 is connected to the negative electrode of the power supply, and the collector of the NPN transistor Q1 is connected to R1; R2 is connected to Z1 in parallel, with one end of R2 connected to R1 and the other end connected to the negative pole of the power supply; the cathode of Z1 is connected to R1, and the anode is connected to the negative pole of the power supply; T1 and RT are set in parallel, one end of RT is connected to the negative pole of the power supply, and the other end is connected to the load; the G pole of T1 is connected to the resistor R1, the S pole is connected to the negative pole of the power supply, and the D pole is connected to the load; It includes a protection module, a battery, a controller, an alarm and a load, and the controller, the alarm and the load are connected in parallel; One end of the protection module is connected to the negative pole of the battery, and the other end is connected to the negative pole of the controller, alarm, and load; Connect the positive pole of the controller, alarm and load to the positive pole of the battery; Including state one: the electric door lock is closed and the immobilizer is in the power-off state, the vehicle is in the non-charging state, the lock rear line has 0 voltage, the base of the NPN transistor Q1 is connected to the negative electrode of the load through R3, the voltage is 0, and it is in the cut-off state, the lock rear line is connected to the voltage divider resistor R1 through the anti-reverse diode D1, at this time there is no voltage across R1 and R2, the gate voltage of T1 is 0, and it is in the off state, and the current can only flow from the negative electrode of the load into B- through RT.

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