CN216285458U - Voltage detection circuit, system and electric automobile - Google Patents

Abstract

The utility model discloses a voltage detection circuit, a voltage detection system and an electric automobile. Wherein, this voltage detection circuit includes: fill electric pile, the battery module, fill positive contactor soon, fill negative contactor soon, first sampling circuit and second sampling circuit, it fills positive contactor soon to be provided with on the circuit between the positive pole of electric pile and the positive pole of battery module, it is provided with on the circuit between the negative pole of electric pile and the negative pole of battery module fills negative contactor soon, wherein, the first end of first sampling circuit is connected on the circuit between the positive pole of electric pile and the first end of filling positive contactor soon, the first end of second sampling circuit is connected on the circuit between the negative pole of electric pile and the first end of filling negative contactor soon, the second end of first sampling circuit is connected with the second end of second sampling circuit. The utility model solves the technical problem that the safety of a battery pack is burnt and other damages are even caused because the voltage outside the quick-charging contactor cannot be detected in the charging process in the related technology.

Description

Voltage detection circuit, system and electric vehicle

technical field

The utility model relates to the technical field of charging, in particular to a voltage detection circuit, a system and an electric vehicle.

Background technique

Fast charging is an important function of electric vehicles, and with the coverage of fast charging piles in various regions of the popularization of electric vehicles in my country, electric vehicle owners are using more and more fast charging functions.

However, with the increase in the number of times of fast charging, there are more and more problems in the process of fast charging. The abnormally large voltage output when the charging pile is turned on for charging causes the battery pack insurance to burn out. One of the problems with larger damage is that at present, electric vehicles in my country rarely test the output voltage of the charging pile. The usual practice is to close the main contactor and fast charging contactor of the battery pack and wait for the voltage input of the fast charging pile. If there is a fault on the side of the fast charging pile at this time, and a voltage with a larger deviation than the battery pack is abnormally output, it will cause a large current to flow through the battery pack instantly, burn the battery pack insurance and even cause other damage. When the gun is charged, there is a large voltage at the end of the charging pile, which may also cause personal injury.

When the electric vehicle is charging, after the initial interaction between the battery management system (Battery Management System, BMS) and the charging pile, the BMS controls the main contactor and fast charging contactor of the whole package to close, waiting for the charging pile to output voltage. The voltage on the outside of the fast charging contactor (the output voltage of the fast charging pile) cannot be detected. If the charging pile abnormally outputs a higher voltage or there is a large voltage on the outside of the fast charging contactor, it will cause a large current to flow through the battery pack instantaneously. , causing damage to components.

After charging, since the BMS cannot detect the voltage on the outside of the fast charging contactor, if the fast charging pile fails, there is an abnormally high voltage outside the fast charging contactor, and there is a risk of personal injury when the charging gun is pulled out.

For the above problems, no effective solution has been proposed yet.

Utility model content

The embodiments of the present invention provide a voltage detection circuit, a system and an electric vehicle, so as to at least solve the technical problem in the related art that the battery pack insurance is burned or even other damages due to the inability to detect the external voltage of the fast charging contactor during the charging process.

According to an aspect of the embodiments of the present invention, a voltage detection circuit is provided, including: a charging pile, a battery module, a fast charging positive contactor, a fast charging negative contactor, a first sampling circuit, and a second sampling circuit , the fast charging positive contactor is provided on the line between the positive pole of the charging pile and the positive pole of the battery module, and the line between the negative pole of the charging pile and the negative pole of the battery module The fast charging negative contactor is provided, wherein the first end of the first sampling circuit is connected to the line between the positive electrode of the charging pile and the first end of the fast charging positive contactor, The first end of the second sampling circuit is connected to the line between the negative electrode of the charging pile and the first end of the fast charging negative contactor, and the second end of the first sampling circuit is connected to the The second end of the second sampling circuit is connected.

Optionally, the first sampling circuit includes a first resistor and a second resistor, and the first end of the first resistor is connected to the positive electrode of the charging pile and the first end of the fast charging positive contactor. On the line between the two, the second end of the first resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the negative electrode of the battery module and the fast charge negative electrode to the line between the second ends of the contactor.

Optionally, the second sampling circuit includes a third resistor and a fourth resistor, and the first end of the third resistor is connected to the negative electrode of the charging pile and the first end of the fast-charging negative contactor. On the line between the three resistors, the second end of the third resistor is connected to the first end of the fourth resistor, and the second end of the fourth resistor is connected to the negative electrode of the battery module and the fast charge negative electrode. to the line between the second ends of the contactor.

Optionally, the circuit further includes: an external load of the vehicle connected to the battery module.

Optionally, the circuit further includes: a main negative relay, wherein the main negative relay is arranged on the first line between the external load of the vehicle and the battery module.

Optionally, the circuit further includes: a main positive relay, wherein the main positive relay is arranged on the second line between the external load of the vehicle and the battery module.

Optionally, the circuit further includes: a precharge contactor, wherein a first end of the precharge contactor is connected to a line between the negative electrode of the battery module and the first end of the main positive relay On the upper side, the second end of the precharge contactor is connected to the line between the second end of the main positive relay and the positive electrode of the external load of the vehicle.

Optionally, the circuit further includes: a pre-charging resistor, wherein the pre-charging resistor is arranged at the second end of the pre-charging contactor and is connected to the second end of the main positive relay and the outside of the vehicle on the line between the positive poles of the load.

According to another aspect of the embodiments of the present invention, a voltage detection system is also provided, the system includes: a battery management system;

According to another aspect of the embodiments of the present invention, an electric vehicle is also provided, and the electric vehicle includes the voltage detection system described above.

In the embodiment of the present invention, the voltage detection circuit includes: a charging pile, a battery module, a fast-charging positive contactor, a fast-charging negative contactor, a first sampling circuit and a second sampling circuit. A fast charging positive contactor is arranged on the line between the positive poles of the battery module, and a fast charging negative contactor is arranged on the line between the negative pole of the charging pile and the negative pole of the battery module. The first end is connected to the line between the positive electrode of the charging pile and the first end of the fast charging positive contactor, and the first end of the second sampling circuit is connected to the negative electrode of the charging pile and the first end of the fast charging negative contactor. On the line between the terminals, the second terminal of the first sampling circuit is connected to the second terminal of the second sampling circuit, and two sampling circuits are added to the voltage detection circuit, which can be used for fast charging before and after charging. The external voltage of the charging contactor is detected, thereby achieving the technical effect of preventing abnormally large voltage input from causing damage to the battery pack components and preventing personal injury caused by the presence of large voltage at the fast charging gun port, thus solving the problem in the related art due to the charging process. The voltage outside the fast charging contactor cannot be detected, causing technical problems such as burning the battery pack insurance or even causing other damages.

Description of drawings

The accompanying drawings described here are used to provide further understanding of the present invention and constitute a part of the present application. The schematic embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention. In the attached image:

1 is a schematic diagram of a voltage detection circuit according to an embodiment of the present invention;

2 is a schematic diagram of a voltage detection circuit according to an alternative embodiment of the present invention.

Wherein, the above-mentioned drawings include the following reference signs:

10. Charging pile; 11. Battery module; 12. Fast charging positive contactor; 13. Fast charging negative contactor; 14. First sampling circuit; 15. Second sampling circuit; 16. Main positive relay; 17 18, precharge relay; 19, precharge resistor; 20, vehicle external load; 141, first resistor; 142, second resistor; 151, third resistor; 152, fourth resistor.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described The embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be noted that the terms "first" and "second" in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific sequence or sequence. . It is to be understood that the data so used may be interchanged under appropriate circumstances so that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having" and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those expressly listed Rather, those steps or units may include other steps or units not expressly listed or inherent to these processes, methods, products or devices.

Example 1

1 is a schematic diagram of a voltage detection circuit according to an embodiment of the present invention. As shown in FIG. 1 , the voltage detection circuit includes: a charging pile 10 , a battery module 11 , a fast charging positive contactor 12 , and a fast charging negative contact 13, the first sampling circuit 14 and the second sampling circuit 15, a fast charging forward contactor 12 is provided on the line between the positive pole of the charging pile 10 and the positive pole of the battery module 11, and the negative pole of the charging pile 10 is connected to the battery module 11. A fast charging negative contactor 13 is provided on the line between the negative poles of the group 11 , wherein the first end of the first sampling circuit 14 is connected between the positive pole of the charging pile 10 and the first end of the fast charging positive contactor 12 . On the line between the two, the first end of the second sampling circuit 15 is connected to the line between the negative electrode of the charging pile 10 and the first end of the fast charging negative contactor 13, and the second end of the first sampling circuit 14 is connected to the The second end of the two-sampling circuit 15 is connected.

In the above-mentioned embodiment of the present utility model, two sampling circuits are added to the voltage detection circuit, which can detect the voltage outside the fast charging contactor before and after the fast charging, so as to prevent abnormally large voltage input. The technical effect of causing damage to the components of the battery pack and preventing personal injury due to the presence of a large voltage at the fast charging gun mouth, thus solves the problem of burning the battery pack insurance and even causing the failure to detect the outside voltage of the fast charging contactor during the charging process in the related art. Other damaging technical issues.

In an optional embodiment, the first sampling circuit 14 includes a first resistor and a second resistor, and the first end of the first resistor is connected to the positive electrode of the charging pile 10 and the first terminal of the fast charging forward contactor 12 . On the line between the terminals, the second terminal of the first resistor is connected to the first terminal of the second resistor, and the second terminal of the second resistor is connected to the negative terminal of the battery module 11 and the second terminal of the fast charge negative contactor 13 . on the line between the terminals.

In an optional embodiment, the second sampling circuit 15 includes a third resistor and a fourth resistor, and the first end of the third resistor is connected to the negative electrode of the charging pile 10 and the first terminal of the fast charging negative contactor 13 On the line between the terminals, the second terminal of the third resistor is connected to the first terminal of the fourth resistor, and the second terminal of the fourth resistor is connected to the negative terminal of the battery module 11 and the second terminal of the fast charge negative contactor 13 . on the line between the terminals.

In an optional embodiment, the above-mentioned circuit further includes: an external load of the whole vehicle, which is connected to the battery module 11 .

It should be noted that the above-mentioned external loads of the vehicle include, but are not limited to, electrical equipment such as the engine, air conditioner, and lighting of the vehicle.

In an optional embodiment, the above circuit further includes: a main negative relay, wherein the main negative relay is arranged on the first line between the external load of the vehicle and the battery module 11 .

In an optional implementation manner, the above circuit further includes: a main positive relay, wherein the main positive relay is arranged on the second line between the external load of the vehicle and the battery module 11 .

In an optional embodiment, the above circuit further includes: a precharge contactor, wherein the first end of the precharge contactor is connected to the line between the negative electrode of the battery module 11 and the first end of the main positive relay , the second end of the precharge contactor is connected to the line between the second end of the main positive relay and the positive pole of the external load of the vehicle.

In an optional embodiment, the above-mentioned circuit further includes: a pre-charging resistor, wherein the pre-charging resistor is arranged at the second end of the pre-charging contactor and is connected to the second end of the main positive relay and the positive electrode of the external load of the whole vehicle on the line between.

An optional embodiment of the present invention will be described in detail below.

FIG. 2 is a schematic diagram of a voltage detection circuit according to an optional embodiment of the present invention. As shown in FIG. 2 , the voltage detection circuit includes: a charging pile 10 , a battery module 11 , a fast charging positive contactor 12 , a fast charging negative To the contactor 13 , the first sampling circuit 14 , the second sampling circuit 15 , the main positive relay 16 , the main negative relay 17 , the precharge relay 18 , the precharge resistor 19 and the vehicle external load 20 , wherein the first sampling circuit 14 It also includes a first resistor 141 and a second resistor 142 , and the second sampling circuit 15 further includes a third resistor 151 and a fourth resistor 152 .

It should be noted that the above voltage detection circuit adds two sampling circuits to the negative of the battery pack outside the fast charging positive contactor and to the negative of the battery pack outside the fast charging negative contactor, and then detects the positive of the fast charging contactor by summing. The purpose of the negative outside voltage. The above-mentioned embodiments of the present invention can not only solve the risk of damage to the components of the battery pack caused by the large voltage outside the fast charging contactor before fast charging, but also solve the problem of personal injury caused by the large voltage outside the fast charging contactor after the fast charging is completed. risks of.

In the specific implementation process, the first sampling circuit measures the negative voltage U1_U0 of the positive outer side of the fast charging contactor to the battery pack, and the second sampling circuit measures the negative voltage U01_U0 of the negative outer side of the fast charging contactor to the battery pack, and calculates the positive voltage of the fast charging contactor. The negative outer voltage is U1_U01=U1_U0+U01_U0.

After this voltage is detected, when it is detected that the voltage of U1_U01 is higher than the voltage of the battery pack after the gun is inserted, the BMS control prohibits entering the charging process; to avoid the abnormal high voltage output by the charging pile from causing damage to the battery pack; when the charging is over, the BMS controls When it is detected that U1_U01 is greater than 60V (human body safety voltage), it is forbidden to disconnect the electronic lock, so as to ensure that the gun is pulled out under unknown circumstances to cause personal injury.

Example 2

According to another aspect of the embodiments of the present invention, a voltage detection system is also provided, the voltage detection system includes: a battery management system; and any one of the above-mentioned voltage detection circuits electrically connected to the battery management system.

Example 3

According to another aspect of the embodiments of the present invention, an electric vehicle is also provided, and the electric vehicle includes the above-mentioned voltage detection system.

The above-mentioned serial numbers of the embodiments of the present invention are only for description, and do not represent the advantages or disadvantages of the embodiments.

In the above-mentioned embodiments of the present invention, the description of each embodiment has its own emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are only illustrative, for example, the division of the units may be a logical function division, and there may be other division methods in actual implementation, for example, multiple units or components may be combined or Integration into another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of units or modules, and may be in electrical or other forms.

The units described as separate components may or may not be physically separated, and components shown as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware, or may be implemented in the form of software functional units.

The integrated unit, if implemented in the form of a software functional unit and sold or used as an independent product, may be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present invention can be embodied in the form of a software product in essence, or the part that contributes to the prior art, or the whole or part of the technical solution, which is stored in a storage medium. , including several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes .

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. These improvements and Retouching should also be regarded as the protection scope of the present invention.

Claims (10)

1. A voltage detection circuit, characterized in that it comprises: a charging pile, a battery module, a fast charging positive contactor, a fast charging negative contactor, a first sampling circuit and a second sampling circuit, and the The fast charging positive contactor is arranged on the line between the positive pole and the positive pole of the battery module, and the fast charging is arranged on the line between the negative pole of the charging pile and the negative pole of the battery module Negative contactor, wherein the first end of the first sampling circuit is connected to the line between the positive pole of the charging pile and the first end of the fast charging positive contactor, and the second sampling circuit The first end of the charging pile is connected to the line between the negative electrode of the charging pile and the first end of the fast charging negative contactor, and the second end of the first sampling circuit is connected to the first end of the second sampling circuit. Two-terminal connection. 2 . The circuit according to claim 1 , wherein the first sampling circuit comprises a first resistor and a second resistor, and a first end of the first resistor is connected to the positive electrode of the charging pile and the On the line between the first ends of the fast charging forward contactor, the second end of the first resistor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the on the line between the negative electrode of the battery module and the second end of the fast charging negative contactor. 3 . The circuit according to claim 1 , wherein the second sampling circuit comprises a third resistor and a fourth resistor, and the first end of the third resistor is connected to the negative electrode of the charging pile and the On the line between the first ends of the fast charging negative contactor, the second end of the third resistor is connected to the first end of the fourth resistor, and the second end of the fourth resistor is connected to the on the line between the negative electrode of the battery module and the second end of the fast charging negative contactor. 4. The circuit according to any one of claims 1 to 3, wherein the circuit further comprises: an external load of the vehicle connected to the battery module. 5 . The circuit according to claim 4 , wherein the circuit further comprises: a main negative relay, wherein the main negative relay is arranged at the first point between the external load of the vehicle and the battery module. 6 . on the line. 6 . The circuit according to claim 4 , wherein the circuit further comprises: a main positive relay, wherein the main positive relay is arranged at the first point between the external load of the vehicle and the battery module. 7 . on the second line. 7 . The circuit according to claim 6 , wherein the circuit further comprises: a precharge contactor, wherein a first end of the precharge contactor is connected to the negative electrode of the battery module and the On the line between the first ends of the main positive relay, the second end of the precharge contactor is connected to the line between the second end of the main positive relay and the positive pole of the external load of the vehicle. 8 . The circuit according to claim 7 , wherein the circuit further comprises: a precharge resistor, wherein the precharge resistor is arranged at the second end of the precharge contactor and is connected to the main positive terminal. 9 . on the line between the second end of the relay and the positive pole of the external load of the vehicle. 9. A voltage detection system, characterized in that the system comprises: battery management system; The voltage detection circuit of any one of the preceding claims 1 to 8 in electrical connection with the battery management system. 10. An electric vehicle, characterized in that the electric vehicle comprises the voltage detection system of claim 9.

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