Over-current protection circuit, intelligent distribution box and new energy automobile

Abstract

The utility model discloses an overcurrent protection circuit, an intelligent power distribution box and a new energy automobile. The overcurrent protection circuit includes: first and second power supplies electrically connected to each other; first and second switches connected in series between the first and second power sources; the sampling resistor is connected in series between the first switch and the second switch; the first controller comprises two first sampling ports which are electrically connected to the first end and the second end of the sampling resistor respectively so as to sample current flowing from the first power supply to the second power supply to obtain sampling current; the first driving port is electrically connected to the first switch so as to turn off the first switch when the sampling current is greater than the threshold current; the second controller comprises two second sampling ports which are electrically connected to the second end and the first end of the sampling resistor respectively so as to sample the current flowing from the second power supply to the first power supply to obtain another sampling current; and a second driving port electrically connected to the second switch to turn off the second switch when the other sampling current is greater than the threshold current.

Description

Technical Field

[0001] The utility model relates to the field of mechanical electronics, and in particular to an overcurrent protection circuit, an intelligent power distribution box comprising the overcurrent protection circuit, and a new energy vehicle comprising the intelligent power distribution box. Background Art

[0002] With the rapid development of new energy vehicles, an increasing number of power sources, such as high-voltage battery packs and auxiliary batteries, are being used to improve their performance. This requires the simultaneous presence of multiple power sources that can power each other. However, if the loads driven by these multiple power sources are short-circuited for various reasons, the supply current between the multiple power sources may be excessive, exceeding the threshold current required for safe operation, and thus risk damaging the power sources.

[0003] In order to reduce this risk, it is urgently necessary to provide an overcurrent protection circuit to promptly cut off the power supply current between the multiple power supplies when the power supply current between the multiple power supplies exceeds a threshold current, thereby achieving overcurrent protection for the multiple power supplies. Utility Model Content

[0004] In view of the above problems, the present invention provides an overcurrent protection circuit, comprising: a first power supply and a second power supply, electrically connected to each other; a first switch and a second switch, connected in series between the first power supply and the second power supply; a sampling resistor, connected in series between the first switch and the second switch; a first controller, comprising: two first sampling ports, electrically connected to the first end and the second end of the sampling resistor, respectively, to sample a current flowing in a first direction from the first power supply toward the second power supply to obtain a first sampling current; and a first driving port, electrically connected to the first switch, to drive the first switch to open when the first sampling current is greater than a threshold current; and a second controller, comprising: two second sampling ports, electrically connected to the second end and the first end of the sampling resistor, respectively, to sample a current flowing in a second direction from the second power supply toward the first power supply to obtain a second sampling current; and a second driving port, electrically connected to the second switch, to drive the second switch to open when the second sampling current is greater than the threshold current.

[0005] According to one aspect of the present invention, the first controller also includes: a first power supply port, electrically connected to one of the first end and the second end; and a first grounding port, used for grounding; and the second controller also includes: a second power supply port, electrically connected to the one end; and a second grounding port, used for grounding.

[0006] According to one aspect of the present invention, the first switch is configured to: when not driven closed by the first drive port, only allow current to flow to the one end in the first direction to power the first controller and the second controller, and when driven closed by the first drive port, allow current to flow in the first direction and the second direction so that the first power supply and the second power supply can power each other.

[0007] According to one aspect of the present invention, the second switch is configured to: when not driven closed by the second drive port, only allow current to flow to the one end in the second direction to power the first controller and the second controller, and when driven closed by the second drive port, allow current to flow in the first direction and the second direction so that the first power supply and the second power supply can power each other.

[0008] According to one aspect of the present invention, the two first sampling ports include: a first positive sampling port electrically connected to the first end to sample a first high potential at the first end when the first switch and the second switch are both driven closed and the current flows in the first direction; and a first negative sampling port electrically connected to the second end to sample a first low potential at the second end when the first switch and the second switch are both driven closed and the current flows in the first direction.

[0009] According to one aspect of the present invention, the two second sampling ports include: a second positive sampling port electrically connected to the second end to sample a second high potential at the second end when the first switch and the second switch are both driven closed and the current flows in the second direction; and a second negative sampling port electrically connected to the first end to sample a second low potential at the first end when the first switch and the second switch are both driven closed and the current flows in the second direction.

[0010] According to one aspect of the present invention, the overcurrent protection circuit further includes: a third controller, operably connected to the first controller and the second controller, and configured to calculate the first sampling current using the following formula: And when the first sampling current is greater than the threshold current, the first controller is instructed to drive the first switch to be disconnected and / or the second controller is instructed to drive the second switch to be disconnected, wherein, I 1s is the first sampling current, U 1h is the first high potential, U 1l is the first low potential, R s is the known sampling resistance value of the sampling resistor; and the second sampling current is calculated using the following formula: And when the second sampling current is greater than the threshold current, the second controller is instructed to drive the second switch to be disconnected and / or the first controller is instructed to drive the first switch to be disconnected, wherein, I 2s is the second sampling current, U 2h is the second highest potential, U 2lis the second lowest potential, R s is the sampling resistor value.

[0011] According to one aspect of the present invention, the third controller is communicatively connected to a display, and the display is configured to display at least one of the values ​​of the following parameters: a first sampling current, a first high potential, a first low potential, a second sampling current, a second high potential, a second low potential, and a sampling resistance value.

[0012] According to one aspect of the present invention, the first switch includes a first N-channel enhancement MOSFET, which has: a first gate electrically connected to a first drive port; a first source electrically connected to a first power supply; a first drain electrically connected to a first end; and a first body diode connected in parallel between the first source and the first drain and having a positive electrode electrically connected to the first source and a negative electrode electrically connected to the first drain to allow current to flow only in a first direction when the first switch is not driven closed by the first drive port.

[0013] According to one aspect of the present invention, the second switch includes a second N-channel enhancement MOSFET, which has: a second gate electrically connected to the second drive port; a second source electrically connected to the second power supply; a second drain electrically connected to the second end; and a second body diode connected in parallel between the second source and the second drain and having a positive electrode electrically connected to the second source and a negative electrode electrically connected to the second drain to allow current to flow only in the second direction when the second switch is not driven closed by the second drive port.

[0014] According to one aspect of the present invention, the first controller and the second controller both include an eFuse chip.

[0015] According to one aspect of the present invention, the first power source includes a battery, and the second power source includes a DC power source.

[0016] According to another aspect of the present invention, an intelligent distribution box is provided, comprising the overcurrent protection circuit according to any of the above aspects.

[0017] According to another aspect of the present invention, a new energy vehicle is provided, comprising the intelligent distribution box according to the above aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above contents and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0019] Figure 1 The figure schematically shows a schematic diagram of an overcurrent protection circuit according to an embodiment of the present utility model. DETAILED DESCRIPTION

[0020] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, it is apparent that one or more embodiments can also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0021] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the presence of the features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0022] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0023] When expressions such as "at least one of A, B, and C, etc." are used, they should generally be interpreted in accordance with the meaning commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0024] See also Figure 1 The present utility model discloses an overcurrent protection circuit 1000, an intelligent power distribution box (not shown in the figure) including the overcurrent protection circuit 1000, and a new energy vehicle (not shown in the figure) including the intelligent power distribution box.

[0025] The overcurrent protection circuit 1000 includes: a first power supply 100 , a second power supply 200 , a first switch 300 , a second switch 400 , a sampling resistor 500 , a first controller 600 , and a second controller 700 .

[0026] The first power source 100 includes, for example, a battery, and the second power source 200 includes, for example, a DC power source. The first power source 100 and the second power source 200 are electrically connected to each other so as to supply power to each other. However, those skilled in the art will appreciate that the present invention is not limited thereto, and the first power source 100 and the second power source 200 may include any suitable type of power source.

[0027] The first switch 300 and the second switch 400 are connected in series between the first power supply 100 and the second power supply 200 to control the on and off of the electrical connection between the first power supply 100 and the second power supply 200. The sampling resistor 500 is connected in series between the first switch 300 and the second switch 400 and has a known sampling resistance value R s , to facilitate sampling of the current flowing through the sampling resistor 500 (as described below).

[0028] The first controller 600 includes two first sampling ports 610 and 620 and a first driving port 630. The two first sampling ports 610 and 620 are electrically connected to the first end 510 and the second end 520 of the sampling resistor 500 respectively to sample the current flowing in the first direction from the first power source 100 to the second power source 200 to obtain a first sampling current I 1s The first driving port 630 is electrically connected to the first switch 300 to generate a first sampling current I 1s Greater than the threshold current I th When the first switch 300 is driven to be turned off.

[0029] The second controller 700 includes two second sampling ports 710 and 720 and a second driving port 730. The two second sampling ports 710 and 720 are electrically connected to the second end 520 and the first end 510 of the sampling resistor 500 respectively to sample the current flowing in the second direction from the second power supply 200 to the first power supply 100 to obtain a second sampling current I 2s The second driving port 730 is electrically connected to the second switch 400 to generate a second sampling current I 2s Greater than the threshold current I th When the second switch 400 is driven to be turned off.

[0030] The first controller 600 and the second controller 700 both include an eFuse chip. However, those skilled in the art should understand that the present invention is not limited thereto, and the first controller 600 and the second controller 700 may include any appropriate type of chip.

[0031] By respectively providing the first controller 600 and the first switch 300, as well as the second controller 700 and the second switch 400, at the two ends 510 and 520 of the sampling resistor 500, the overcurrent protection circuit 1000 is capable of collecting currents flowing in opposite first and second directions, and is capable of performing overcurrent protection on the first power supply 100 and the second power supply 200 in these two opposite directions. This greatly improves the overcurrent protection capability of the first power supply 100 and the second power supply 200, which is particularly important for circuit systems including more (for example, three or more) power supplies.

[0032] Continue to refer to Figure 1The first controller 600 further includes: a first power supply port 640 for receiving current from the first power source 100 and / or the second power source 200 to power the first controller 600 and a first grounding port 650 for grounding. Figure 1 In the embodiment, the first power supply port 640 is electrically connected to the second end 520 . However, those skilled in the art should understand that the first power supply port 640 may also be electrically connected to the first end 510 .

[0033] The second controller 700 further includes: a second power supply port 740 for receiving current from the first power supply 100 and / or the second power supply 200 to power the second controller 700, and a second grounding port 750 for grounding. The second power supply port 740 is electrically connected to the second end 520. As can be seen, the first controller 600 and the second controller 700 are connected in parallel, and the potentials at the first power supply port 640 and the second power supply port 740 are both V s .

[0034] The first switch 300 is configured to: when not driven closed by the first drive port 630, only allow current to flow along the first direction to the second end 520 to power the first controller 600 and the second controller 700, and when driven closed by the first drive port 630, allow current to flow along the first direction and the second direction to enable the first power supply 100 and the second power supply 200 to power each other.

[0035] The second switch 400 is configured to: when not driven closed by the second drive port 730, only allow current to flow along the second direction to the second end 520 to power the first controller 600 and the second controller 700, and when driven closed by the second drive port 730, allow current to flow along the first direction and the second direction to enable the first power supply 100 and the second power supply 200 to power each other.

[0036] The two first sampling ports 610 and 620 include a first positive sampling port 610 and a first negative sampling port 620. The first positive sampling port 610 is electrically connected to the first end 510 to sense the first high potential U at the first end 510 when the first switch 300 and the second switch 400 are both driven to close and the current flows in the first direction. 1h The first negative sampling port 620 is electrically connected to the second end 520 to sample the first low potential U at the second end 520 when the first switch 300 and the second switch 400 are both driven to close and the current flows in the first direction. 1l Take samples.

[0037] The two second sampling ports 710 and 720 include a second positive sampling port 710 and a second negative sampling port 720. The second positive sampling port 710 is electrically connected to the second end 520 to sense the second high potential U at the second end 520 when the first switch 300 and the second switch 400 are both driven to close and the current flows in the second direction. 2h The second negative sampling port 720 is electrically connected to the first end 510 to sample the second low potential U at the first end 510 when the first switch 300 and the second switch 400 are both driven to close and the current flows in the second direction. 2l Take samples.

[0038] The overcurrent protection circuit 1000 further includes a third controller 800 operatively connected to the first controller 600 and the second controller 700 via communication links 810 and 820 , respectively, and configured to:

[0039] Use formula (1) according to the first high potential U 1h , first low potential U 1l , and the known sampling resistance value R of the sampling resistor 500 s Calculate the first sampling current I 1s :

[0040] (1)

[0041] And in the first sampling current I 1s Greater than the threshold current I th instructing the first controller 600 to drive the first switch 300 to be disconnected and / or instructing the second controller 700 to drive the second switch 400 to be disconnected; and

[0042] Use formula (2) according to the second high potential U 2h , the second low potential U 2l , and the sampling resistor value R s Calculate the second sampling current I 2s :

[0043] (2)

[0044] And in the second sampling current I 2s Greater than the threshold current I th The second controller 700 is instructed to drive the second switch 400 to be disconnected and / or the first controller 600 is instructed to drive the first switch 300 to be disconnected.

[0045] The third controller 800 is in communication connection with a display (not shown) via a communication link 830 , and the display is configured to display at least one of the values ​​of the following parameters: the first sampling current I1s , the first high potential U 1h , first low potential U 1l , the second sampling current I 2s , the second high potential U 2h , the second low potential U 2l , and the sampling resistor value R s .

[0046] The first switch 300 includes a first N-channel enhancement-mode MOSFET having a first gate G1, a first source S1, a first drain D1, and a first body diode 310. The first gate G1 is electrically connected to the first drive port 630. The first source S1 is electrically connected to the first power source 100. The first drain D1 is electrically connected to the first terminal 510. The first body diode 310 is connected in parallel between the first source S1 and the first drain D1 and has an anode electrically connected to the first source S1 and a cathode electrically connected to the first drain D1. When the first switch 300 is not driven closed by the first drive port 630, current is allowed to flow only in a first direction, thereby providing power to the first controller 600 and / or the second controller 700.

[0047] The second switch 400 includes a second N-channel enhancement-mode MOSFET having a second gate G2, a second source S2, a second drain D2, and a second body diode 410. The second gate G2 is electrically connected to the second drive port 730. The second source S2 is electrically connected to the second power source 200. The second drain D2 is electrically connected to the second terminal 520. The second body diode 410 is connected in parallel between the second source S2 and the second drain D2 and has an anode electrically connected to the second source S2 and a cathode electrically connected to the second drain D2. When the second switch 400 is not driven closed by the second drive port 730, it only allows current to flow in the second direction, thereby providing power to the first controller 600 and / or the second controller 700.

[0048] However, those skilled in the art should understand that the first switch 300 and the second switch 400 are not limited to N-channel enhancement mode MOSFETs, and the first switch 300 and the second switch 400 may include any suitable type of switches.

[0049] The embodiments of the present invention have been described in detail with reference to the accompanying drawings. It should be noted that any implementations not depicted or described in the drawings or the main text of the specification are known to those skilled in the art and are not described in detail. Furthermore, the definitions of the various components described above are not limited to the specific structures, shapes, or methods described in the embodiments; those skilled in the art may easily modify or replace them.

[0050] It should also be noted that, in the specific embodiments of the present invention, unless otherwise indicated, the numerical parameters in this specification and the appended claims are approximate values ​​and can vary depending on the desired properties obtained through the content of the present invention. Specifically, all numbers used in the specification and claims to express compositional dimensions, range conditions, etc. should be understood to be modified by the term "about" in all cases. Generally, the meaning of the expression is to include variations of ±10% in some embodiments, ±5% in some embodiments, ±1% in some embodiments, and ±0.5% in some embodiments from the specific quantity.

[0051] Those skilled in the art will appreciate that various combinations and / or combinations of features described in the various embodiments and / or claims of the present invention may be employed, even if such combinations and / or combinations are not explicitly described in the present invention. In particular, various combinations and / or combinations of features described in the various embodiments and / or claims of the present invention may be employed without departing from the spirit and teachings of the present invention. All such combinations and / or combinations fall within the scope of the present invention.

[0052] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific 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 overcurrent protection circuit, characterized in that: include: A first power source and a second power source are electrically connected to each other; A first switch and a second switch are connected in series between the first power supply and the second power supply; a sampling resistor connected in series between the first switch and the second switch; The first controller includes: two first sampling ports, electrically connected to a first end and a second end of a sampling resistor, respectively, to sample a current flowing in a first direction from the first power source toward the second power source to obtain a first sampling current; and a first driving port, electrically connected to the first switch, to drive the first switch to be disconnected when the first sampling current is greater than a threshold current; and The second controller includes: two second sampling ports, respectively electrically connected to the second end and the first end of the sampling resistor to sample the current flowing in a second direction from the second power supply to the first power supply to obtain a second sampling current; and a second driving port, electrically connected to the second switch to drive the second switch to open when the second sampling current is greater than a threshold current.

2. The overcurrent protection circuit according to claim 1, characterized in that: The first controller further includes: a first power supply port electrically connected to one of the first end and the second end; and a first ground port for grounding; and The second controller further includes: a second power supply port electrically connected to the one end; and a second grounding port for grounding.

3. The overcurrent protection circuit according to claim 2, wherein: The first switch is configured to: when not driven closed by the first drive port, only allow current to flow to the one end in a first direction to power the first controller and the second controller, and when driven closed by the first drive port, allow current to flow in the first direction and the second direction to enable the first power supply and the second power supply to power each other.

4. The overcurrent protection circuit according to claim 3, characterized in that: The second switch is configured to: when not driven closed by the second drive port, only allow current to flow to the one end in the second direction to power the first controller and the second controller, and when driven closed by the second drive port, allow current to flow in the first direction and the second direction to enable the first power supply and the second power supply to power each other.

5. The overcurrent protection circuit according to claim 4, characterized in that: The two first sampling ports include: a first positive sampling port electrically connected to the first end to sample a first high potential at the first end when both the first switch and the second switch are driven closed and current flows in a first direction; and The first negative sampling port is electrically connected to the second end to sample a first low potential at the second end when both the first switch and the second switch are driven to close and current flows in a first direction.

6. The overcurrent protection circuit according to claim 5, characterized in that: The two second sampling ports include: a second positive sampling port electrically connected to the second end to sample a second high potential at the second end when both the first switch and the second switch are driven closed and current flows in the second direction; and The second negative sampling port is electrically connected to the first end to sample a second low potential at the first end when the first switch and the second switch are both driven to close and the current flows in the second direction.

7. The overcurrent protection circuit according to claim 6, characterized in that: Also includes: A third controller is operatively connected to the first controller and the second controller, respectively, and is configured to: Use the following formula to calculate the first sampling current: And when the first sampling current is greater than the threshold current, the first controller is instructed to drive the first switch to be disconnected and / or the second controller is instructed to drive the second switch to be disconnected, wherein, I 1s is the first sampling current, U 1h is the first high potential, U 1l is the first low potential, R s is the known sampling resistance value of the sampling resistor; and Use the following formula to calculate the second sampling current: And when the second sampling current is greater than the threshold current, the second controller is instructed to drive the second switch to be disconnected and / or the first controller is instructed to drive the first switch to be disconnected, wherein, I 2s is the second sampling current, U 2h is the second highest potential, U 2l is the second lowest potential, R s is the sampling resistor value.

8. The overcurrent protection circuit according to claim 7, characterized in that: The third controller is in communication with a display, wherein the display is configured to display at least one of the values ​​of the following parameters: A first sampling current, a first high potential, a first low potential, a second sampling current, a second high potential, a second low potential, and a sampling resistance value.

9. The overcurrent protection circuit according to any one of claims 4 to 8, characterized in that: The first switch includes a first N-channel enhancement-mode MOSFET having: a first gate electrically connected to the first driving port; a first source electrode electrically connected to a first power source; a first drain electrode electrically connected to the first terminal; and The first body diode is connected in parallel between the first source and the first drain and has an anode electrically connected to the first source and a cathode electrically connected to the first drain, so as to only allow current to flow in a first direction when the first switch is not driven closed by the first driving port.

10. The overcurrent protection circuit according to claim 9, characterized in that: The second switch includes a second N-channel enhancement-mode MOSFET having: a second gate electrically connected to the second driving port; a second source electrode electrically connected to a second power source; a second drain electrode electrically connected to the second terminal; and The second body diode is connected in parallel between the second source and the second drain and has an anode electrically connected to the second source and a cathode electrically connected to the second drain, so as to only allow current to flow in the second direction when the second switch is not driven closed by the second driving port.

11. The overcurrent protection circuit according to any one of claims 1 to 8 and 10, characterized in that: The first controller and the second controller both include an eFuse chip.

12. The overcurrent protection circuit according to claim 11, characterized in that: The first power source includes a battery, and the second power source includes a DC power source.

13. An intelligent distribution box, characterized in that: The device comprises an overcurrent protection circuit according to any one of claims 1 to 12.

14. A new energy vehicle, characterized in that: Comprising the intelligent distribution box according to claim 13.

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