Contactor state detection device, method, battery system and electric vehicle

Abstract

The present invention discloses a contactor state detection device, method, battery system and electric vehicle, the device includes: a switch unit and a controller, the controller is connected to the switch unit, used to obtain a first voltage to a sixth voltage, and also used to control the on-off state of the switch unit to switch the detection mode, and when switching to the first detection mode, the state of the positive contactor and the negative contactor is judged according to the first voltage, the second voltage, the third voltage and the first preset reference voltage, and / or, when switching to the second detection mode, the state of the fast-charging positive contactor and the fast-charging negative contactor is judged according to the fourth voltage, the fifth voltage, the sixth voltage and the second preset reference voltage. The present invention only uses one controller to control the switching of the detection mode, completes the detection of the corresponding contactor state in the corresponding detection mode, solves the problem of requiring the contactor action timing when performing contactor state detection, and reduces the product cost.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to a contactor state detection device, method, battery system and electric vehicle. Background Art

[0002] The positive contactor, negative contactor, fast-charging positive contactor and fast-charging negative contactor are important components in the vehicle's high-voltage system. The stability of the status of these contactors is crucial to the safe operation of the entire high-voltage system. Therefore, the status of the contactors needs to be regularly inspected for maintenance.

[0003] At present, in the related technology, the contactor status detection method mainly includes a single-chip detection method and a dual-chip detection method.

[0004] However, the single-chip detection method has requirements for the contactor action timing when performing contactor status diagnosis. The fast-charging positive and negative contactor status can only be diagnosed when the positive and negative contactor status is closed. In addition, when the vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the fast-charging positive and negative contactor status cannot be determined. If the fast-charging positive and negative contactors are both stuck, the fast-charging positive and negative contactor status diagnosis can only be performed after high voltage, and it is impossible to timely identify whether there is voltage at the high-voltage charging port, so there may be a risk of electric shock to the human body. In addition, the fast-charging positive and negative contactors are disconnected first after charging is completed. In order to keep the positive and negative contactors closed, the positive and negative contactors must be disconnected only after the fast-charging positive and negative contactor status diagnosis is completed. The contactor action timing causes the power-off time to be extended. If the charging fault ends, the positive and negative contactors cannot be disconnected in time, which will pose a safety risk.

[0005] The dual-chip detection method requires two chips to work simultaneously, which will increase product costs. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0007] To this end, an object of the present invention is to propose a contactor state detection device, which can complete the detection of the contactor state with a controller, solves the problem of requiring the contactor action timing when performing contactor state detection, shortens the power-off time, and at the same time reduces product costs, improves the safety of detection and facilitates advance detection.

[0008] Therefore, a second object of the present invention is to provide a contactor state detection method.

[0009] To this end, a third object of the present invention is to provide a battery system.

[0010] To this end, a fourth object of the present invention is to provide an electric vehicle.

[0011] To achieve the above-mentioned objectives, an embodiment of the first aspect of the present invention discloses a contactor state detection device, comprising: a switch unit, wherein the switch unit is used to switch the detection device to a first detection mode or a second detection mode through its own on-off state, wherein in the first detection mode, the front end of the negative pole contactor is used as the first high-voltage reference ground, and in the second detection mode, the front end of the fast-charging negative pole contactor is used as the second high-voltage reference ground; a controller, wherein the controller is connected to the switch unit and is used to obtain a first voltage to a sixth voltage, wherein the first voltage is the voltage of the front end of the positive pole contactor relative to the first high-voltage reference ground, the second voltage is the voltage of the rear end of the positive pole contactor relative to the first high-voltage reference ground, the third voltage is the voltage of the rear end of the negative pole contactor relative to the first high-voltage reference ground, and the fourth voltage is the voltage of the rear end of the positive pole contactor relative to the second high-voltage reference ground. The fifth voltage is the voltage of the rear end of the fast charging positive contactor relative to the second high-voltage reference ground, and the sixth voltage is the voltage of the rear end of the fast charging negative contactor relative to the second high-voltage reference ground, wherein the rear end of the positive contactor is connected to the front end of the fast charging positive contactor, and the front end of the fast charging negative contactor is connected to the rear end of the negative contactor; the controller is also used to control the on and off state of the switch unit to switch the detection mode, and when switching to the first detection mode, the state of the positive contactor and the negative contactor is judged according to the first voltage, the second voltage, the third voltage and the first preset reference voltage, and / or, when switching to the second detection mode, the state of the fast charging positive contactor and the fast charging negative contactor is judged according to the fourth voltage, the fifth voltage, the sixth voltage and the second preset reference voltage.

[0012] According to the contactor state detection device of the embodiment of the invention, by setting the first high-voltage reference ground and the second high-voltage reference ground, the voltage corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, is obtained. The controller switches the detection mode according to the on-off state of the switch unit, so as to detect the state of the positive and negative contactors in the first detection mode, and detect the fast-charging positive and negative contactors in the second detection mode, so that there is no requirement for the contactor action timing when performing contactor state detection, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the controller can control the detection device to switch to the second detection mode to detect the state of the fast-charging positive and negative contactors. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the fast-charging positive and negative contactors is completed. They can be disconnected immediately and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast-charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, one controller can be used to complete the detection of the contactor state, reducing product costs.

[0013] In addition, the contactor state detection device according to the above embodiment of the present invention may also have the following additional technical features:

[0014] In some embodiments, the switch unit includes: a first switch, which is arranged between the front end of the positive contactor and the front end of the negative contactor; a second switch, which is arranged between the rear end of the positive contactor and the rear end of the negative contactor; when the controller controls the first switch to be turned on and controls the second switch to be turned off, the detection device switches to the first detection mode; when the controller controls the first switch to be turned off and controls the second switch to be turned on, the detection device switches to the second detection mode.

[0015] In some embodiments, the contactor state detection device further includes: a preset power supply, wherein the preset power supply is used to provide the first preset reference voltage and the second preset reference voltage.

[0016] In some embodiments, the preset power supply includes: a first preset power supply, the first preset power supply is used to provide the first preset reference voltage; and a second preset power supply, the second preset power supply is used to provide the second preset reference voltage.

[0017] In some embodiments, the contactor state detection device also includes: a voltage acquisition unit, which is used to collect voltages from the first channel to the fifth channel, wherein the two ends of the first channel are the front end of the positive contactor and the front end of the negative contactor, respectively, the two ends of the second channel are the rear end of the positive contactor and the front end of the negative contactor, respectively, the two ends of the third channel are the rear end of the fast charging positive contactor and the front end of the fast charging negative contactor, respectively, the two ends of the fourth channel are the first preset power supply and the rear end of the negative contactor, respectively, and the two ends of the fifth channel are the second preset power supply and the rear end of the fast charging negative contactor, respectively; a voltage calculation unit, which is used to calculate the first voltage according to the voltage of the first channel, and calculate the second voltage according to the voltage of the second channel, and calculate the third voltage according to the voltage of the fourth channel, and calculate the fourth voltage according to the voltage of the second channel, and calculate the fifth voltage according to the voltage of the third channel, and calculate the sixth voltage according to the voltage of the fifth channel; the voltage calculation unit is also used to input the first voltage to the sixth voltage into the controller.

[0018] In some embodiments, the contactor state detection device also includes: a voltage acquisition unit, which is used to collect voltages from the first channel to the fifth channel, wherein the two ends of the first channel are the front end of the positive contactor and the front end of the negative contactor, respectively, the two ends of the second channel are the rear end of the positive contactor and the front end of the negative contactor, respectively, the two ends of the third channel are the rear end of the fast charging positive contactor and the front end of the fast charging negative contactor, respectively, the two ends of the fourth channel are the first preset power supply and the rear end of the negative contactor, respectively, and the two ends of the fifth channel are the second preset power supply and the rear end of the fast charging negative contactor, respectively; then the controller is specifically used to calculate the first voltage according to the voltage of the first channel, and calculate the second voltage according to the voltage of the second channel, and calculate the third voltage according to the voltage of the fourth channel, and calculate the fourth voltage according to the voltage of the second channel, and calculate the fifth voltage according to the voltage of the third channel, and calculate the sixth voltage according to the voltage of the fifth channel.

[0019] In some embodiments, the voltage collection unit includes: a first voltage collection unit, the first voltage collection unit is connected between the front end of the positive contactor and the front end of the negative contactor; a second voltage collection unit, the second voltage collection unit is connected between the rear end of the positive contactor and the front end of the negative contactor; a third voltage collection unit, the third voltage collection unit is connected between the rear end of the fast charging positive contactor and the front end of the fast charging negative contactor; a fourth voltage collection unit, the fourth voltage collection unit is connected between the first preset power supply and the rear end of the negative contactor; a fifth voltage collection unit, the fifth voltage collection unit is connected between the second preset power supply and the rear end of the fast charging negative contactor.

[0020] In some embodiments, each of the first to fifth voltage acquisition units includes at least two voltage-dividing resistors connected in series.

[0021] In some embodiments, in the first detection mode, the controller determines the state of the positive contactor based on the first voltage and the second voltage, and the controller determines the state of the negative contactor based on the third voltage and the first preset reference voltage.

[0022] In some embodiments, the controller is used to: when the absolute value of the difference between the first voltage and the second voltage is less than a first set threshold, determine that the positive contactor is in a closed state; otherwise, determine that the fast charging positive contactor is in an open state.

[0023] In some embodiments, the controller is used to: when the absolute value of the difference between the third voltage and the first preset reference voltage is less than a second set threshold, determine that the negative contactor is in an open state; otherwise, determine that the negative contactor is in a closed state.

[0024] In some embodiments, in the second detection mode, the controller determines the state of the fast charging positive contactor based on the fourth voltage and the fifth voltage, and the controller determines the state of the fast charging negative contactor based on the sixth voltage and the second preset reference voltage.

[0025] In some embodiments, the controller is used to: when the absolute value of the difference between the fourth voltage and the fifth voltage is less than a third set threshold, determine that the fast charging positive contactor is in a closed state; otherwise, determine that the positive contactor is in an open state.

[0026] In some embodiments, the controller is used to: when the absolute value of the difference between the sixth voltage and the second preset reference voltage is less than a fourth set threshold, determine that the fast charging negative pole contactor is in a disconnected state; otherwise, determine that the fast charging negative pole contactor is in a closed state.

[0027] To achieve the above-mentioned purpose, an embodiment of the second aspect of the present invention discloses a contactor state detection method, which is used for the contactor state detection device described in the embodiment of the first aspect of the present invention. The detection method includes: obtaining a first voltage to a sixth voltage, the first voltage is the voltage of the front end of the positive contactor relative to the first high-voltage reference ground, the second voltage is the voltage of the rear end of the positive contactor relative to the first high-voltage reference ground, the third voltage is the voltage of the rear end of the negative contactor relative to the first high-voltage reference ground, the fourth voltage is the voltage of the rear end of the positive contactor relative to the second high-voltage reference ground, the fifth voltage is the voltage of the rear end of the fast-charging positive contactor relative to the second high-voltage reference ground, and the sixth voltage is the voltage of the rear end of the fast-charging negative contactor relative to the second high-voltage reference ground, wherein the rear end of the positive contactor is connected to the fast-charging positive contactor. The front end of the contactor is connected, and the front end of the fast charging negative contactor is connected to the rear end of the negative contactor; the on-off state of the switch unit is controlled to switch the detection device to the first detection mode or the second detection mode, wherein, in the first detection mode, the front end of the negative contactor is the first high-voltage reference ground, and in the second detection mode, the front end of the fast charging negative contactor is the second high-voltage reference ground; when switching to the first detection mode, the states of the positive contactor and the negative contactor are judged according to the first voltage, the second voltage, the third voltage and the first preset reference voltage, and / or, when switching to the second detection mode, the states of the fast charging positive contactor and the fast charging negative contactor are judged according to the fourth voltage, the fifth voltage, the sixth voltage and the second preset reference voltage.

[0028] According to the contactor state detection method of the embodiment of the present invention, by setting the first high-voltage reference ground and the second high-voltage reference ground, and obtaining the voltages corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, and then switching the detection mode according to the on-off state of the switch unit, the positive and negative contactor states are detected in the first detection mode, and the fast charging positive and negative contactors are detected in the second detection mode, so that there is no requirement for the contactor action timing when performing contactor state detection, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the detection device can be controlled to switch to the second detection mode to detect the states of the fast charging positive and negative contactors. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the fast charging positive and negative contactors is completed. They can be disconnected immediately and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, one controller can be used to complete the contactor state detection, thereby reducing product cost.

[0029] To achieve the above-mentioned purpose, an embodiment of a third aspect of the present invention discloses a battery system, comprising the contactor state detection device described in the embodiment of the first aspect of the present invention.

[0030] According to the battery system of the embodiment of the present invention, by setting the first high-voltage reference ground and the second high-voltage reference ground, the voltages corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, are obtained, and the controller switches the detection mode according to the on-off state of the switch unit, so as to detect the state of the positive and negative contactors in the first detection mode, and detect the fast-charging positive and negative contactors in the second detection mode, so that there is no requirement for the contactor action timing when the contactor state detection is performed, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the controller can control the detection device to switch to the second detection mode to detect the state of the fast-charging positive and negative contactors. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the fast-charging positive and negative contactors is completed. They can be disconnected immediately and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast-charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, one controller can be used to complete the contactor state detection, thereby reducing product cost.

[0031] To achieve the above-mentioned purpose, an embodiment of a fourth aspect of the present invention discloses an electric vehicle, comprising the battery system described in the embodiment of the third aspect of the present invention.

[0032] According to the electric vehicle of the embodiment of the present invention, by setting the first high-voltage reference ground and the second high-voltage reference ground, the voltages corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, are obtained, and the controller switches the detection mode according to the on-off state of the switch unit, so as to detect the state of the positive and negative contactors in the first detection mode, and detect the fast-charging positive and negative contactors in the second detection mode, so that there is no requirement for the contactor action timing when the contactor state detection is performed, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the controller can control the detection device to switch to the second detection mode to detect the state of the fast-charging positive and negative contactors. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the fast-charging positive and negative contactors is completed. They can be disconnected immediately and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast-charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, one controller can be used to complete the detection of the contactor state, thereby reducing the product cost.

[0033] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0035] Figure 1 is a circuit diagram of a single chip detection method according to the related art;

[0036] Figure 2 is a circuit diagram of a dual chip detection method according to the related art;

[0037] Figure 3 is a structural block diagram of a contactor state detection device according to an embodiment of the present invention;

[0038] Figure 4 is a circuit diagram of a contactor state detection device according to an embodiment of the present invention;

[0039] Figure 5 is a circuit diagram of a detection device according to an embodiment of the present invention switched to a first detection mode;

[0040] Figure 6 is a circuit diagram of a detection device switched to a second detection mode according to an embodiment of the present invention;

[0041] Figure 7 is a flow chart of a contactor state detection method according to an embodiment of the present invention;

[0042] Figure 8 is a flow chart of positive contactor state detection according to one embodiment of the present invention;

[0043] Fig. 9 is a flow chart of negative contactor state detection according to one embodiment of the present invention;

[0044] Fig.10 is a flow chart of fast charging positive contactor state detection according to one embodiment of the present invention;

[0045] Fig.11 4 is a flow chart of fast charging negative contactor status detection according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0047] In the related art, contactor status detection methods generally include a single-chip detection method and a dual-chip detection method.

[0048] Specifically, Figure 1As shown, the single-chip detection method uses a high-voltage acquisition chip ASIC (Application Specific Integrated Circuit) to detect the contactor status. ASIC is a special integrated chip. The single-chip detection method sets a high-voltage reference ground to realize high-voltage acquisition of each high-voltage acquisition point based on the high-voltage reference ground. By setting multiple voltage-dividing resistors in the acquisition circuit, the corresponding voltage-dividing resistors can constitute a corresponding voltage-dividing circuit. ASIC can obtain the corresponding voltage according to the corresponding voltage-dividing circuit, thereby calculating the voltage of each high-voltage reference point in the acquisition circuit to the high-voltage reference ground, and then comparing the voltage of each high-voltage reference point in the acquisition circuit to the high-voltage reference ground, it can judge the state of the positive contactor, the state of the negative contactor, the state of the fast-charging positive contactor, and the state of the fast-charging negative contactor one by one.

[0049] However, the single-chip detection method has requirements for the contactor action timing when performing contactor status diagnosis. The fast-charging positive and negative contactor status can only be diagnosed when the positive contactor status is closed. In addition, when the vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the fast-charging positive and negative contactor status cannot be determined. If the fast-charging positive and negative contactors are both stuck, the fast-charging positive and negative contactor status diagnosis can only be performed after high voltage, and it is impossible to timely identify whether there is voltage at the high-voltage charging port, so there may be a risk of electric shock to the human body. In addition, the fast-charging positive and negative contactors are disconnected first after charging is completed. In order to keep the positive and negative contactors closed, the positive and negative contactors must be disconnected after the fast-charging positive and negative contactor status diagnosis is completed. The contactor action timing causes the power-off time to be extended. If the charging fault ends, the positive and negative contactors cannot be disconnected in time, which will pose a safety risk. Moreover, the voltage acquisition circuit is directly connected between the positive and negative poles of the battery pack to form a discharge circuit, which can easily lead to over-discharge of the battery pack in the long run.

[0050] In addition, if Figure 2 As shown, the dual-chip detection method uses two high-voltage acquisition chips ASIC, one of which is denoted as ASIC1, which acquires the voltage of each high-voltage acquisition point to the first reference ground, and the other is denoted as ASIC2, which acquires the voltage of each high-voltage acquisition point to the second high-voltage reference ground.

[0051] Specifically, ASIC1 mainly diagnoses the status of the positive contactor and the negative contactor. ASIC1 collects the voltage of the voltage-dividing circuit composed of multiple voltage-dividing resistors to calculate the voltage of each high-voltage collection point to the first high-voltage reference ground based on these voltages, and then compares the calculated voltage of each high-voltage collection point to the first high-voltage reference ground, and determines the status of the positive and negative contactors according to the comparison results. Similarly, ASIC2 collects the voltage of the voltage-dividing circuit composed of the remaining multiple voltage-dividing resistors to calculate the voltage of each high-voltage collection point to the second high-voltage reference ground based on these voltages, and then compares the calculated voltage of each high-voltage collection point to the second high-voltage reference ground, and determines the status of the fast-charging positive and negative contactors according to the comparison results.

[0052] However, the dual-chip detection method uses two chips to detect the contactor status. Although it solves the problem of the single-chip detection method having requirements for the contactor action timing when diagnosing the contactor status, it increases the product cost and does not solve the problem that the voltage acquisition circuit in the single-chip detection method is directly connected between the positive and negative poles of the battery pack to form a discharge circuit, which can easily lead to over-discharge of the battery pack in the long run.

[0053] Based on the above, the present invention uses a high-voltage acquisition chip to realize contactor status detection, which reduces costs. There is no requirement for the contactor action timing when performing contactor status detection, which shortens the power-off time. It can also issue early warning information to avoid electric shock caused by human contact with the high-voltage charging port, thereby improving the safety of detection.

[0054] Reference below Figure 3-Figure 6 A contactor state detection device according to an embodiment of the present invention is described.

[0055] Figure 3 is a structural block diagram of a contactor state detection device according to an embodiment of the present invention. Figure 4 FIG. 1 is a circuit diagram of a contactor state detection device according to an embodiment of the present invention. Figure 3 As shown, the contactor state detection device 1 mainly includes: a switch unit 112 and a controller 110 .

[0056] Among them, combined Figure 4As shown, the controller 110 is used to obtain the first voltage to the sixth voltage, the first voltage is the voltage of the front end of the positive contactor F1 relative to the first high-voltage reference ground, the second voltage is the voltage of the rear end of the positive contactor F1 relative to the first high-voltage reference ground, the third voltage is the voltage of the rear end of the negative contactor F2 relative to the first high-voltage reference ground, the fourth voltage is the voltage of the rear end of the positive contactor F1 relative to the second high-voltage reference ground, the fifth voltage is the voltage of the rear end of the fast-charging positive contactor F3 relative to the second high-voltage reference ground, and the sixth voltage is the voltage of the rear end of the fast-charging negative contactor F4 relative to the second high-voltage reference ground, wherein the rear end of the positive contactor F1 is connected to the front end of the fast-charging positive contactor F3, and the front end of the fast-charging negative contactor F4 is connected to the rear end of the negative contactor F2.

[0057] For example, combined with Figure 4 As shown, the front end of the positive contactor F1 is recorded as PACK+, the rear end of the positive contactor F1 is recorded as LINK+, the rear end of the negative contactor F2 is recorded as LINK-, the rear end of the fast charging positive contactor F3 is recorded as DC+, the rear end of the fast charging negative contactor F4 is recorded as DC-, the first high voltage reference ground is recorded as PACK-, the second high voltage reference ground is recorded as LINK-, and the first voltage is recorded as V PACK+ , the second voltage is recorded as V LINK+ , the third voltage is recorded as V LINK- , the fourth voltage is recorded as V LINK+ ', the fifth voltage is recorded as V DC+ , the sixth voltage is recorded as V DC- .

[0058] Among them, the front end of the above-mentioned positive contactor F1 refers to its end connected to the positive pole of the battery pack 120, and the rear end of the positive contactor F1 refers to its end connected to one end of the high-voltage discharge port 130; the front end of the negative contactor F2 refers to its end connected to the negative pole of the battery pack 120, and the rear end of the negative contactor F2 refers to its end connected to the other end of the high-voltage discharge port 130; the rear end of the fast-charging positive contactor F3 refers to its end connected to one end of the high-voltage charging port 140; the rear end of the fast-charging negative contactor F4 refers to its end connected to the other end of the high-voltage charging port 140.

[0059] Specifically, the controller 110 can obtain the first voltage V PACK+ , the second voltage V LINK+ , the third voltage V LINK- , the fourth voltage V LINK+ ', the fifth voltage V DC+ and the sixth voltage V DC-, so that the controller 110 can judge the state of the contactor according to these voltages, for example, whether the positive contactor F1 is in a closed state or an open state. There is no requirement for the contactor action timing when performing contactor state detection, that is, whether the positive contactor F1 is closed or not, the state of the fast-charging positive contactor F3 can be detected; whether the state of the negative contactor F2 is closed or not, the state of the fast-charging negative contactor F4 can be detected. In addition, by setting the first high-voltage reference ground PACK- and the second high-voltage reference ground LINK-, the voltage corresponding to the high-voltage reference ground can be obtained, so as to realize the state detection of the positive contactor F1 and the negative contactor F2 at the voltage corresponding to the first high-voltage reference ground PACK-, and realize the state detection of the fast-charging positive contactor F3 and the fast-charging negative contactor F4 at the voltage corresponding to the second high-voltage reference ground LINK-.

[0060] Switching unit( Figure 4 (not shown) is used to switch the detection device to the first detection mode or the second detection mode through its own on and off state. Figure 4 As shown, in the first detection mode, the front end of the negative pole contactor F2 is used as the first high-voltage reference ground, denoted as PACK-, and in the second detection mode, the front end of the fast-charging negative pole contactor F4 is used as the second high-voltage reference ground, denoted as LINK-.

[0061] Specifically, the switch unit can control the detection mode of the detection device through its own on-off state, that is, it can enable the detection device to switch between a first detection mode and a second detection mode, and these two detection modes correspond to different high-voltage reference grounds respectively.

[0062] Combination Figure 5 and Figure 6 As shown, in the first detection mode, the front end of the negative electrode contactor F2 is used as the first high-voltage reference ground PACK-; in the second detection mode, the front end of the fast-charging negative electrode contactor F4 is used as the second high-voltage reference ground LINK-.

[0063] The controller 110 is connected to the switch unit and is used to control the on / off state of the switch unit to switch the detection mode. When switching to the first detection mode, the controller 110 controls the on / off state of the switch unit to switch the detection mode according to the first voltage V PACK +, the second voltage V LINK+ , the third voltage V LINK- and the first preset reference voltage to determine the state of the positive contactor F1 and the negative contactor F2, and / or, when switching to the second detection mode, according to the fourth voltage V LINK+ ', the fifth voltage V DC+ , the sixth voltage V DC- And the second preset reference voltage is used to determine the status of the fast charging positive contactor F3 and the fast charging negative contactor F4.

[0064] Specifically, combined Figure 5 and Figure 6 As shown, the controller 110 includes, for example, a high-voltage acquisition chip ASIC. The controller 110 is connected to the switch unit and can control the on / off state of the switch unit to switch the detection mode. When the detection device is switched to the first detection mode, the controller 110 can obtain the first voltage V PACK+ , the second voltage V LINK+ , the third voltage V LINK- and the first preset reference voltage is, for example, V VREF1 to determine the state of the positive contactor F1 and the negative contactor F2; when the detection device is switched to the second detection mode, the controller 110 can obtain the fourth voltage V LINK+ ', the fifth voltage V DC+ , the sixth voltage V DC- and a second preset reference voltage (e.g., V VREF2 ) is used to determine the status of the fast charging positive contactor F3 and the fast charging negative contactor F4, thereby realizing the detection of the contactor status.

[0065] In a specific embodiment, Figure 4 As shown, the front end PACK+ of the positive contactor F1 is connected to the positive pole of the battery pack 120, the rear end LINK+ of the positive contactor F1 is connected to one end of the high-voltage discharge port 130, the front end of the negative contactor F2 is connected to the negative pole of the battery pack 120, and the rear end LINK- of the negative contactor F2 is connected to the other end of the high-voltage discharge port 130; the rear end DC+_ of the fast-charging positive contactor F3 is connected to one end of the high-voltage charging port 140, and the rear end DC- of the fast-charging negative contactor F4 is connected to the other end of the high-voltage charging port 140.

[0066] Specifically, the front end PACK+ of the positive contactor F1 is connected to the positive electrode of the battery pack 120, so that the positive electrode voltage of the battery pack 120 can be transmitted to the positive contactor F1, and the rear end LINK+ of the positive contactor F1 is connected to one end of the high-voltage discharge port 120, so that the rear end LINK+ of the positive contactor F1 guides the voltage of the positive part to the high-voltage discharge port 130, ensuring that the positive electrode voltage of the battery pack 120 can be further transmitted to the high-voltage discharge port 130, so as to perform a discharge operation when needed; the front end of the negative contactor F2 is connected to the negative electrode of the battery pack 120, so that the negative electrode voltage of the battery pack 120 can be transmitted to the negative contactor F2, and the rear end LINK- of the negative contactor F2 is connected to the other end of the high-voltage discharge port 130, so that the negative electrode voltage of the battery pack 120 can be further transmitted to the high-voltage discharge port 130, forming a negative side connection of the high-voltage discharge port 130.

[0067] The rear end DC+ of the fast charging positive contactor F3 is connected to one end of the high-voltage charging port 140, so that the high-voltage charging port 140 can receive the positive voltage through the fast charging positive contactor F3, and the rear end DC- of the fast charging negative contactor F4 is connected to the other end of the high-voltage charging port 140, forming a negative side connection of the high-voltage charging port 140, so that the high-voltage charging port 140 can receive the negative voltage through the fast charging negative contactor F4, thereby controlling the state of the positive and negative contactors and the fast charging positive and negative contactors, and the charging and discharging state of the vehicle can be controlled.

[0068] Thus, in an embodiment of the present invention, by setting a first high-voltage reference ground and a second high-voltage reference ground, the voltages corresponding to each high-voltage reference ground, i.e., the first voltage to the sixth voltage, are obtained. The controller switches the detection mode according to the on-off state of the switch unit, so as to detect the state of the positive and negative contactors in the first detection mode, and detect the fast-charging positive and negative contactors in the second detection mode, so that there is no requirement for the contactor action timing when the contactor state detection is performed, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the controller can control the detection device to switch to the second detection mode to detect the state of the fast-charging positive and negative contactors. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the fast-charging positive and negative contactors is completed. The positive and negative contactors can be disconnected immediately, and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast-charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, one controller can be used to complete the detection of the contactor state, thereby reducing the product cost.

[0069] In one embodiment of the present invention, Figure 5 As shown, in the first detection mode, the controller 110 detects the voltage V PACK+ and the second voltage V LINK+ to determine the state of the positive contactor F1, and the controller 110 determines the state of the positive contactor F1 according to the third voltage V LINK- and a first preset reference voltage V VREF1 To determine the state of the negative contactor F2.

[0070] In an embodiment, Figure 5 As shown, when the detection device switches to the first detection mode, by comparing the first voltage V PACK+ and the second voltage V LINK+ The controller 110 generates a voltage V PACK+ and the second voltage V LINK+ The absolute value of the difference between the positive contactor F1 and the positive contactor F1 is used to determine the state of the positive contactor F1, for example, whether the positive contactor F1 is in a closed state or an open state. At the same time, by comparing the third voltage V LINK- and the first preset reference voltage V VREF1The controller 110 generates a voltage V LINK- and the first preset reference voltage V VREF 1 is used to determine the state of the negative contactor F2, so that in the first detection mode, the controller 110 determines the state of the negative contactor F2 according to the first voltage V PACK+ , the second voltage V LINK+ , the third voltage V LINK- and a first preset reference voltage V VREF1 Complete the detection of the status of the positive contactor F1 and the negative contactor F2.

[0071] In one embodiment of the present invention, Figure 5 As shown, the controller 110 is used to: when the first voltage V PACK+ and the second voltage V LINK+ When the absolute value of the difference is less than the first set threshold, it is determined that the positive contactor F1 is in a closed state; otherwise, it is determined that the positive contactor F1 is in an open state.

[0072] In an embodiment, when the first voltage V PACK+ and the second voltage V LINK+ When the absolute value of the difference is less than the first set threshold, for example, the range of the first set threshold is 10V to 20V, if the first set threshold is set to 10V, that is, |VP ACK+ -VL INK+ |<10, the controller 110 determines that the positive contactor F1 is in a closed state; if the first voltage V PACK+ and the second voltage V LINK+ The absolute value of the difference is greater than or equal to the first set threshold, that is, |V PACK+ -V LINK+ |≥10, the controller 110 determines that the positive contactor F1 is in the disconnected state, because the first voltage V PACK+ is the voltage of the front end PACK+ of the positive contactor F1 relative to the first high voltage reference ground PACK-, and the second voltage V LINK+ is the voltage of the rear end LINK+ of the positive contactor F1 relative to the first high voltage reference ground PACK-. If the positive contactor F1 is in the closed state, the first voltage V PACK+ and the second voltage V LINK+ The value is very close, that is, the first voltage V PACK+ and the second voltage V LINK+ The absolute value of the difference is small. If the positive contactor F1 is in the disconnected state, the first voltage V PACK+ and the second voltage V LINK+ The values ​​of may differ significantly, therefore, by comparing the first voltage V PACK+ and the second voltage V LINK+The state of the positive contactor F1 can be detected by the absolute value of the difference and the first set threshold.

[0073] In one embodiment of the present invention, Figure 5 As shown, the controller 110 is used to: when the third voltage V LINK- and the first preset reference voltage V VREF1 When the absolute value of the difference is less than the second set threshold, it is determined that the negative contactor F2 is in the open state; otherwise, it is determined that the negative contactor F2 is in the closed state.

[0074] In an embodiment, when the third voltage V LINK- and the first preset reference voltage V VREF1 When the absolute value of the difference is less than the second set threshold, for example, the range of the second set threshold is 10V to 20V, if the second set threshold is set to 10V, that is, |V LINK+ -V VREF1 |≤10, the controller 110 determines that the negative contactor F2 is in the disconnected state, which can be understood as the third voltage V LINK- and the first preset reference voltage V VREF1 When the voltage value of is close to that of the negative pole contactor F2, the negative pole contactor F2 is in the disconnected state; if the third voltage V LINK- and the first preset reference voltage V VREF1 The absolute value of the difference is greater than or equal to the second set threshold, that is, |V LINK+ -V VREF1 |≥10, the controller 110 determines that the negative contactor F2 is in a closed state. Therefore, the controller 110 determines the state of the negative contactor F2 by acquiring the voltage information and sets a suitable second set threshold, thereby improving the accuracy of the negative contactor F2 state detection.

[0075] In one embodiment of the present invention, Figure 6 As shown, in the second detection mode, the controller 110 detects the voltage V LINK+ ' and the fifth voltage V DC+ To determine the state of the fast charging positive contactor F3, and the controller 110 according to the sixth voltage V DC- and a second preset reference voltage V VREF2 To determine the status of the fast charging negative pole contactor F4.

[0076] In an embodiment, Figure 6 As shown, when the detection device is switched to the second detection mode, the controller 110 compares the fourth voltage V LINK+ ' and the fifth voltage V DC+ The voltage of the fourth voltage V LINK+ ' and the fifth voltage VDC+ The absolute value of the difference between the fast charge positive contactor F3 and the fast charge positive contactor F4 determines whether the fast charge positive contactor F3 is in a closed state or an open state. At the same time, the controller 110 also obtains the sixth voltage V DC- and a second preset reference voltage V VREF2 The state of the fast charging negative electrode contactor F4 is determined, so that in the second detection mode, the controller 110 detects the state of the negative electrode contactor F4 according to the fourth voltage V LINK+ ', the fifth voltage V DC+ , the sixth voltage V DC- and a second preset reference voltage V VREF2 Complete the detection of the status of the fast charging positive contactor F3 and the fast charging negative contactor F4.

[0077] In one embodiment of the present invention, Figure 6 As shown, the controller 110 is used to: when the fourth voltage V LINK+ ' and the fifth voltage V DC+ When the absolute value of the difference is less than the third set threshold, it is determined that the fast charging positive contactor F3 is in a closed state; otherwise, it is determined that the fast charging positive contactor F3 is in a disconnected state.

[0078] In an embodiment, when the fourth voltage V LINK+ ' and the fifth voltage V DC+ When the absolute value of the difference between |V is less than the third set threshold, for example, the range of the third set threshold is 10V to 20V, if the third set threshold is set to 10V, that is, |V LINK+ ′-V DC+ |≤10, the controller 110 will determine that the fast charging positive contactor F3 is in a closed state, which can also be understood as the fourth voltage V LINK+ ' and the fifth voltage V DC+ When the voltage value of is close to that of the fast charge positive contactor F3, the fast charge positive contactor F3 is in a closed state; if the fourth voltage V LINK+ ' and the fifth voltage V DC+ The absolute value of the difference is greater than or equal to the third set threshold, that is, |V LINK+ ′-V DC+ |≥10, the controller 110 will determine that the fast charging positive contactor F3 is in the disconnected state. Therefore, the controller 110 determines the state of the fast charging positive contactor F3 by acquiring the voltage information and sets a suitable third setting threshold, thereby improving the accuracy of the fast charging positive contactor F3 state detection.

[0079] In one embodiment of the present invention, Figure 6 As shown, the controller 110 is used to: when the sixth voltage V DC- and a second preset reference voltage V VREF2When the absolute value of the difference is less than the fourth set threshold, it is determined that the fast charging negative electrode contactor F4 is in the open state; otherwise, it is determined that the fast charging negative electrode contactor F4 is in the closed state.

[0080] In the embodiment, when the sixth voltage V DC- and a second preset reference voltage V VREF 2 is less than the fourth set threshold, for example, the range of the fourth set threshold is 10V to 20V, if the fourth set threshold is set to 10V, that is, |V DC- -V VREF2 |≤10, that is, the sixth voltage V DC- and a second preset reference voltage V VREF2 When the voltage value of the sixth voltage V is close to that of the sixth voltage V, the controller 110 will determine that the fast charging negative electrode contactor F4 is in the disconnected state; DC- and a second preset reference voltage V VREF2 The absolute value of the difference between |V DC- -V VREF2 |≥10, that is, the sixth voltage V DC- and a second preset reference voltage V VREF2 When the voltage values ​​differ greatly, the controller 110 will determine that the fast charging negative pole contactor F4 is in a closed state. Therefore, the controller 110 can judge the state of the fast charging negative pole contactor F4 based on the acquired voltage information, and improve the accuracy of the fast charging negative pole contactor F4 state detection by setting an appropriate fourth setting threshold.

[0081] In one embodiment of the present invention, Figure 4 As shown, the switch unit includes: a first switch Q1 and a second switch Q2, the first switch Q1 is arranged between the front end PACK+ of the positive contactor F1 and the front end of the negative contactor F2; the second switch Q2 is arranged between the rear end LINK+ of the positive contactor F1 and the rear end LINK- of the negative contactor F2; when the controller 110 controls the first switch Q1 to be turned on and controls the second switch Q2 to be turned off, the detection device switches to the first detection mode; when the controller 110 controls the first switch Q1 to be turned off and controls the second switch Q2 to be turned on, the detection device switches to the second detection mode.

[0082] In an embodiment, Figure 4As shown, the controller switches the detection mode by controlling the on-off state of the first switch Q1 and the second switch Q2. The first switch Q1 is arranged between the front end PACK+ of the positive contactor F1 and the front end of the negative contactor F2, and the second switch Q2 is arranged between the rear end LINK+ of the positive contactor F1 and the rear end LINK- of the negative contactor F2. The signal port corresponding to the first switch Q1 is the first port IOl, and the signal port corresponding to the second switch Q2 is the second port 102. The controller 110 controls the on-off of the first switch Q1 and the second switch Q2 by controlling the output levels of the first port IOl and the second port 102.

[0083] Specifically, when the controller 110 controls the first port IO1 to output a high level and controls the second port IO2 to output a low level, the first switch Q1 is in an on state and the second switch Q2 is in an off state. At this time, the detection device switches to the first detection mode; when the controller 110 controls the first port IO1 to output a low level and the second port IO2 to output a high level, the first switch Q1 is in an off state and the second switch Q2 is in an on state. At this time, the detection device switches to the second detection mode.

[0084] It can also be understood that when the controller 110 is in a working state and needs to collect the voltage of the battery pack 120, the states of the first switch Q1 and the second switch Q2 are controlled by controlling the first port IO1 and the second port IO2, and the voltage collection short circuit can be connected to the positive and negative electrodes of the battery pack 120 through the turned-on first switch Q1 and the second switch Q2, thereby performing voltage collection; if the controller 110 is in a non-working state, the first port IO1 and the second port IO2 are controlled to output a low level, then the first switch Q1 and the second switch Q2 are both in a disconnected state, at this time, it can be ensured that the voltage collection circuit will not be directly connected between the positive and negative electrodes of the battery pack 120, thereby avoiding the formation of a discharge loop, effectively preventing the battery pack 120 from being over-discharged, and thereby protecting the safety of the battery pack 120.

[0085] Combination Figure 5 and Figure 6 As shown, the controller switches the detection mode by controlling the on / off state of the first switch Q1 and the second switch Q2. The first switch Q1 and the second switch Q2 can use an optical coupler, a relay, an electronic switch, etc. as an isolation switch device. When the first switch Q1 is closed and the second switch Q2 is disconnected, as shown in FIG. Figure 2 As shown, the detection device switches to the first detection mode. In the first detection mode, the front end of the negative contactor F2 is used as the first high-voltage reference ground PACK-; when the first switch Q1 is disconnected and the second switch Q2 is closed, as shown in FIG. Figure 3 As shown, the detection device switches to the second detection mode. In the second detection mode, the front end of the fast charging negative electrode contactor F4 is used as the second high-voltage reference ground LINK-.

[0086] In one embodiment of the present invention, Figure 4 As shown, the contactor state detection device also includes: a preset power supply (not shown in the figure), the preset power supply is used to provide a first preset reference voltage V VREF1 and a second preset reference voltage V VREF2 .

[0087] In an embodiment, Figure 1 As shown, the contactor state detection device also includes a preset power supply, which can provide a first preset reference voltage V VREF1 and a second preset reference voltage V VREF2 , that is, the relevant voltage value is added to detect the contactor state, for example, the first preset reference voltage V VREF1 It is possible to determine the state of the negative contactor F2, the second preset reference voltage V VREF2 It is possible to determine the state of the fast charging negative electrode contactor F4, wherein the first preset reference voltage V VREF1 and a second preset reference voltage V VREF2 For example, it is 2.5V or 5V, that is, the first preset reference voltage V VREF1 and a second preset reference voltage V VREF2 The voltages can be the same or different.

[0088] In one embodiment of the present invention, Figure 4 As shown, the preset power supply includes: a first preset power supply and a second preset power supply, and the first preset power supply is used to provide a first preset reference voltage V VREF1 The second preset power supply is used to provide a second preset reference voltage V VREF2 .

[0089] The first preset power source is, for example, recorded as VREF1, and the second preset power source is, for example, recorded as VREF2.

[0090] In an embodiment, Figure 4 As shown, the first preset reference voltage V provided by the first preset power supply VREF1 VREF1 , can be used as a comparison benchmark for judging the state of the negative contactor F2. Similarly, the second preset voltage VREF2 provides a second preset reference voltage V VREF2 , which can be used as a comparison benchmark for judging the status of the fast-charging negative contactor F4.

[0091] In one embodiment of the present invention, the contactor state detection device 1 further includes: a voltage acquisition unit (not shown in the figure) and a voltage calculation unit (not shown in the figure).

[0092] The voltage acquisition unit is used to collect the voltages of the first channel to the fifth channel, wherein the voltage acquisition unit is used to collect the voltages of the first channel to the fifth channel. Figure 5 and Figure 6 As shown, the two ends of the first channel are the front end PACK+ of the positive contactor F1 and the front end of the negative contactor F2, the two ends of the second channel are the rear end LINK+ of the positive contactor F1 and the front end of the negative contactor F2, the two ends of the third channel are the rear end DC+ of the fast charging positive contactor F3 and the front end of the fast charging negative contactor F4, the two ends of the fourth channel are the first preset power supply VREF1 and the rear end of the negative contactor F2, and the two ends of the fifth channel are the second preset power supply VREF2 and the rear end DC- of the fast charging negative contactor F4.

[0093] The voltage calculation unit is used to calculate the first voltage V according to the voltage of the first channel. PACK+ , and calculate the second voltage V according to the voltage of the second channel LINK+ , and calculate the third voltage V according to the voltage of the fourth channel LINK- , and calculate the fourth voltage V according to the voltage of the second channel LINK+ ', and calculate the fifth voltage V according to the voltage of the third channel DC+ , and calculate the sixth voltage V according to the voltage of the fifth channel DC- .

[0094] The voltage calculation unit is further configured to input the calculated first to sixth voltages to the controller 110 , so that the controller 110 acquires the first to sixth voltages.

[0095] In the embodiment, for example, the voltage of the first channel is recorded as V1, the voltage of the second channel is recorded as V2, the voltage of the third channel is recorded as V3, the voltage of the fourth channel is recorded as V4, and the voltage of the fifth channel is recorded as V5.

[0096] like Figure 5 As shown, in the first detection mode, the controller 110 controls the first port IO1 to output a high level to control the first switch Q1 to be turned on, and controls the second port IO2 to output a low level to control the second switch Q2 to be turned off. At this time, the voltage acquisition unit can collect the voltage relative to the first high-voltage reference ground PACK-, that is, collect the voltage V1 of the first channel, the voltage V2 of the second channel and the voltage V4 of the fourth channel.

[0097] Specifically, Figure 5 As shown, the voltage calculation unit can calculate the first voltage V according to the voltage V1 of the first channel. PACK+ , that is, the voltage of the front end PACK+ of the positive contactor F1 relative to the first high voltage reference ground PACK- is calculated according to the voltage V1 of the first channel, and the first voltage-dividing resistor R1 and the second voltage-dividing resistor R2 in the first channel are collected by the voltage collection unit, and the voltage V1 of the first channel can be obtained according to the first voltage-dividing resistor R1 and the second voltage-dividing resistor R2, that is, V1=V PACK+*R2 / (R1+R2), thus, the voltage calculation unit can calculate the first voltage V according to the voltage V1 of the first channel. PACK+ , that is, V PACK+ =V1*(R1+R2) / R2.

[0098] Similarly, if Figure 5 As shown, the voltage calculation unit can calculate the second voltage V according to the voltage V2 of the second channel. LINK+ , that is, the voltage of the rear end LINK+ of the positive contactor F1 relative to the first high-voltage reference ground PACK- is calculated according to the voltage V2 of the second channel, and the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4 in the second channel are collected by the voltage acquisition unit, and the voltage V2 of the second channel can be obtained according to the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4, that is, V2=V LINK+ *R4 / (R3+R4), thus, the voltage calculation unit can calculate the second voltage V according to the voltage V2 of the second channel. LINK+ , that is, V LINK+ =V2*(R3+R4) / R4.

[0099] The voltage calculation unit can calculate the third voltage V according to the voltage V4 of the fourth channel. LINK- , that is, the voltage of the rear end LINK- of the negative contactor F2 relative to the first high-voltage reference ground PACK- is calculated according to the voltage V4 of the fourth channel, and the seventh voltage-dividing resistor R7 and the eighth voltage-dividing resistor R8 in the fourth channel are collected by the voltage collection unit, and the voltage V4 of the fourth channel can be obtained according to the seventh voltage-dividing resistor R7 and the eighth voltage-dividing resistor R8. Therefore, the voltage calculation unit can calculate the third voltage V according to the voltage V4 of the fourth channel. LINK- , that is, V LINK- =V4.

[0100] like Figure 6 As shown, in the second detection mode, the controller 110 controls the first port IO1 to output a low level to control the first switch Q1 to be disconnected, and controls the second port IO2 to output a high level to control the second switch Q2 to be closed. At this time, the voltage acquisition unit can acquire the voltage relative to the second high-voltage reference ground LINK-, that is, it can acquire the voltage V2' of the second channel, the voltage V3 of the third channel and the voltage V4 of the fifth channel.

[0101] Specifically, Figure 6 As shown, the voltage calculation unit can calculate the fourth voltage V according to the voltage V2' of the second channel. LINK+', that is, the voltage of the rear end LINK+ of the positive contactor F1 relative to the second high voltage reference ground LINK- is calculated according to the voltage V2' of the second channel, and the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4 in the second channel are collected by the voltage collection unit, and the voltage V2' of the second channel can be obtained according to the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4, that is, V2'=V LINK+ '*R4 / (R3+R4), thus, the voltage calculation unit can calculate the fourth voltage V according to the voltage V2' of the second channel. LINK+ ', that is, V LINK+ '=V2'*(R3+R4) / R4.

[0102] The voltage calculation unit can calculate the fifth voltage V according to the voltage V3 of the third channel. DC+ , that is, the voltage of the rear end DC+ of the fast charging positive contactor F3 relative to the second high voltage reference ground LINK- is calculated according to the voltage V3 of the third channel, and the fifth voltage-dividing resistor R5 and the sixth voltage-dividing resistor R6 in the third channel are collected by the voltage acquisition unit, and the voltage V3 of the third channel can be obtained according to the fifth voltage-dividing resistor R5 and the sixth voltage-dividing resistor R6, that is, V3=V DC+ *R6 / (R5+R6), thus, the voltage calculation unit can calculate the fifth voltage V according to the voltage V3 of the third channel. DC+ , that is, V DC+ =V3*(R5+R6) / R6.

[0103] The voltage calculation unit can calculate the sixth voltage V according to the voltage V5 of the fifth channel. DC- , that is, the voltage of the rear end DC- of the fast charging negative contactor F4 relative to the second high-voltage reference ground LINK- is calculated according to the voltage V5 of the fifth channel, and the ninth voltage-dividing resistor R9 and the tenth voltage-dividing resistor R10 in the fifth channel are collected through the voltage acquisition unit, and the unit V5 of the fifth channel can be obtained according to the ninth voltage-dividing resistor R9 and the tenth voltage-dividing resistor R10, that is, V5=V DC- *R10 / (R9+R10), thus, the voltage calculation unit can calculate the sixth voltage V according to the voltage V5 of the fifth channel. DC- , that is, V DC- =V5*(R9+R10) / R10.

[0104] The voltage calculation unit calculates the first voltage V according to the voltage of each channel. PACK+ To the sixth voltage V DC- After that, the first voltage V PACK+ To the sixth voltage V DC- is input to the controller 110, so that the controller 110 can obtain the first voltage V PACK+ To the sixth voltage V DC- .

[0105] In summary, by controlling the voltage states of the first port IO1 and the second port IO2, if the outputs of the first port IO1 and the second port IO2 are high level, the first switch Q1 and the second switch Q2 are in a closed state, and if the outputs of the first port IO1 and the second port IO2 are low level, the first switch Q1 and the second switch Q2 are in a disconnected state, that is, according to the states of the first switch Q1 and the second switch Q2, the detection mode can be switched, thereby avoiding the problem of detecting the first voltage V PACK+ , the second voltage V LINK+ , the fifth voltage V DC+ During the process, the voltage acquisition circuit is directly connected between the positive and negative electrodes of the battery pack to form a discharge loop, resulting in the risk of over-discharge of the battery pack.

[0106] Thus, in the first detection mode, by comparing the first voltage V PACK+ and the second voltage V LINK+ The state of the positive contactor F1 can be determined by comparing the third voltage V LINK- and the first preset reference voltage V REF1 The state of the negative contactor F2 can be determined; in the second detection mode, by comparing the fourth voltage V LINK+ ' and the fifth voltage V DC+ The state of the fast-charging positive contactor F3 can be determined by comparing the sixth voltage V DC- and a second preset reference voltage V REF2 The state of the fast-charging negative electrode contactor F4 can be determined, thereby completing the detection of the contactor state.

[0107] In another specific embodiment of the present invention, the contactor state detection device 1 further includes: a voltage acquisition unit (not shown in the figure). The voltage acquisition unit may be, for example, the voltage acquisition unit described in the above embodiment of the present invention.

[0108] Among them, the voltage acquisition unit is used to collect the voltages of the first channel to the fifth channel, wherein the two ends of the first channel are the front end PACK+ of the positive contactor F1 and the front end of the negative contactor F2, respectively, the two ends of the second channel are the rear end LINK+ of the positive contactor F1 and the front end of the negative contactor F2, respectively, the two ends of the third channel are the rear end DC+ of the fast charging positive contactor F3 and the front end of the fast charging negative contactor F4, respectively, the two ends of the fourth channel are the first preset power supply VREF1 and the rear end of the negative contactor F2, respectively, and the two ends of the fifth channel are the second preset power supply VREF2 and the rear end DC- of the fast charging negative contactor F4.

[0109] Based on this, the controller 110 is specifically configured to calculate the first voltage V according to the voltage of the first channel. PACK+ , and calculate the second voltage V according to the voltage of the second channelLINK+ , and calculate the third voltage V according to the voltage of the fourth channel LINK- , and calculate the fourth voltage V according to the voltage of the second channel LINK+ ', and calculate the fifth voltage V according to the voltage of the third channel DC+ , and calculate the sixth voltage V according to the voltage of the fifth channel DC- Thus, the controller 110 can obtain the first voltage to the sixth voltage.

[0110] That is, the controller 110 may have a voltage calculation function, that is, the controller 110 may calculate the first voltage to the sixth voltage respectively according to the voltage of each channel collected by the voltage collection unit. Specifically, in the first detection mode, after the voltage collection unit collects the voltage V1 of the first channel, the controller 110 calculates the first voltage V according to the voltage V1 of the first channel. PACK+ After the voltage acquisition unit acquires the voltage V2 of the second channel, the controller 110 can calculate the second voltage V according to the voltage V2 of the second channel. LINK+ After the voltage acquisition unit acquires the voltage V4 of the fourth channel, the controller 110 may calculate the third voltage V according to the voltage V4 of the fourth channel. LINK- .

[0111] Similarly, in the second detection mode, after the voltage acquisition unit acquires the voltage V2' of the second channel, the controller 110 can calculate the fourth voltage V according to the voltage V2' of the second channel. LINK+ After the voltage acquisition unit acquires the voltage V3 of the third channel, the controller 110 can calculate the fifth voltage V according to the voltage V3 of the third channel. DC+ After the voltage acquisition unit acquires the voltage V5 of the fifth channel, the controller 110 can calculate the sixth voltage V according to the voltage V5 of the fifth channel. DC- .

[0112] It should be noted that the specific calculation method in which the controller 110 obtains the first voltage to the sixth voltage based on the voltage calculations of each channel is similar to the specific calculation method in which the voltage calculation unit of the above-mentioned embodiment calculates the first voltage to the sixth voltage. The above-mentioned calculation process can be referred to for details. In order to reduce redundancy, it will not be listed here.

[0113] Therefore, after the voltage acquisition unit acquires the voltage of each channel, the controller 110 calculates the first voltage to the sixth voltage according to the voltage of each channel. Therefore, on the basis that the controller 110 has the voltage calculation function, it is possible to avoid adding additional components with the voltage calculation function, reduce the physical connection between components, improve the integration, and save the component layout space.

[0114] In one embodiment of the present invention, Figure 5 and Figure 6 As shown, the voltage acquisition unit includes: a first voltage acquisition unit (not shown in the figure), the first voltage acquisition unit is connected between the front end PACK+ of the positive contactor F1 and the front end of the negative contactor F2; a second voltage acquisition unit (not shown in the figure), the second voltage acquisition unit is connected between the rear end LINK+ of the positive contactor F1 and the front end of the negative contactor F2; a third voltage acquisition unit (not shown in the figure), the third voltage acquisition unit is connected between the rear end DC+ of the fast charging positive contactor F3 and the front end of the fast charging negative contactor F4; a fourth voltage acquisition unit (not shown in the figure), the fourth voltage acquisition unit is connected between the first preset power supply and the rear end LINK- of the negative contactor F2; a fifth voltage acquisition unit (not shown in the figure), the fifth voltage acquisition unit is connected between the second preset power supply and the rear end DC- of the fast charging negative contactor F4.

[0115] In an embodiment, Figure 5 As shown, when the detection device is in the first detection mode, the first voltage acquisition unit is connected between the front end PACK+ of the positive contactor F1 and the front end of the negative contactor F2, and is used to collect the voltage V1 of the first channel. The voltage calculation unit calculates the first voltage V according to the voltage V1 of the first channel. PACK+ The second voltage acquisition unit is connected between the rear end LINK+ of the positive contactor F1 and the front end of the negative contactor F2, and is used to collect the voltage V2 of the second channel. The voltage calculation unit calculates the second voltage V according to the voltage V2 of the second channel. LINK+ The fourth voltage acquisition unit is connected between the first preset power supply VREF1 and the rear end LINK- of the negative contactor F2, and is used to collect the voltage V4 of the fourth channel. The voltage calculation unit calculates the third voltage V according to the voltage V4 of the third channel. LINK- .

[0116] like Figure 6 As shown, when the detection device is in the second detection mode, the second voltage acquisition unit is connected between the rear end LINK+ of the positive contactor F1 and the front end of the negative contactor F2, and is used to collect the voltage V2' of the second channel. The voltage calculation unit calculates the fourth voltage V according to the voltage V2' of the second channel. LINK+ The third voltage acquisition unit is connected between the first preset power supply VREF1 and the rear end LINK- of the negative contactor F2, and is used to collect the voltage V3 of the third channel. The voltage calculation unit calculates the fifth voltage V according to the unit V3 of the third channel. DC+ The fifth voltage acquisition unit is connected between the second preset power supply VREF2 and the rear end DC- of the fast charging negative electrode contactor F4, and is used to collect the voltage V5 of the fifth channel. The voltage calculation unit calculates the sixth voltage V according to the unit V5 of the fifth channel. DC- .

[0117] In one embodiment of the present invention, Figure 5 and Figure 6 As shown, the first voltage acquisition unit to the fifth voltage acquisition unit respectively include at least two voltage dividing resistors connected in series.

[0118] In an embodiment, each voltage acquisition unit includes at least two voltage-dividing resistors connected in series, so as to acquire the voltage in each channel according to a voltage-dividing circuit formed by these voltage-dividing resistors.

[0119] Specifically, Figure 5 As shown, in the first detection mode, the first voltage acquisition unit acquires the voltage V1 of the first channel, the first channel includes the first voltage-dividing resistor R1 and the second voltage-dividing resistor R2, the first voltage-dividing resistor R1 and the second voltage-dividing resistor R2 constitute the voltage-dividing circuit of the first channel, then the first voltage acquisition unit can acquire the voltage V1 of the first channel according to the voltage-dividing circuit; the second acquisition unit acquires the voltage V2 of the second channel, the second channel includes the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4, the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4 constitute the voltage-dividing circuit of the second channel, then the second voltage acquisition unit can acquire the voltage V2 of the second channel according to the voltage-dividing circuit; the fourth voltage acquisition unit acquires the voltage V4 of the fourth channel, the fourth channel includes the seventh voltage-dividing resistor R7 and the eighth voltage-dividing resistor R8, the seventh voltage-dividing resistor R7 and the eighth voltage-dividing resistor R8 can constitute the voltage-dividing circuit of the fourth channel, then the fourth voltage acquisition unit can acquire the voltage V4 of the fourth channel according to the voltage-dividing circuit.

[0120] like Figure 6 As shown, in the second detection mode, the second voltage acquisition unit acquires the voltage V2' of the second channel, the second channel includes the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4, the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4 constitute the voltage-dividing circuit of the second channel, and the second voltage acquisition unit can obtain the voltage V2' of the second channel according to the voltage-dividing circuit; the third voltage acquisition unit acquires the voltage V3 of the third channel, the third channel includes the fifth voltage-dividing resistor R5 and the sixth voltage-dividing resistor R6, the fifth voltage-dividing resistor R5 and the sixth voltage-dividing resistor R6 constitute the voltage-dividing circuit of the third channel, and the third voltage acquisition unit can acquire the voltage V3 of the third channel according to the voltage-dividing circuit; the fifth voltage acquisition unit can acquire the voltage V5 of the fifth channel, the fifth channel includes the ninth voltage-dividing resistor R9 and the tenth voltage-dividing resistor R10, the ninth voltage-dividing resistor R9 and the tenth voltage-dividing resistor R10 constitute the voltage-dividing circuit of the fifth channel, and the fifth voltage acquisition unit can acquire the voltage V5 of the fifth channel according to the voltage-dividing circuit, thereby realizing the accurate acquisition of the voltages of each channel and improving the accuracy of the contactor state detection.

[0121] Among them, the first voltage-dividing resistor R1 to the tenth voltage-dividing resistor R10 are high-voltage acquisition voltage-dividing resistors, so as to convert the voltage of the high-voltage acquisition point corresponding to each high-voltage reference ground into a voltage recognizable by the voltage acquisition unit according to these high-voltage acquisition voltage-dividing resistors, that is, the voltage of the first channel to the fifth channel (V1~V5), and then calculate the voltage of the corresponding high-voltage acquisition point according to the voltage of the first channel to the fifth channel (V1~V5), that is, calculate the first voltage V PACK+ To the sixth voltage V DC- .

[0122] In summary, combined Figure 4 As shown, the overall structure and connection relationship of the contactor state detection device of the embodiment of the present invention can be summarized as follows: the positive electrode of the battery pack 120 is connected to the front end PACK+ of the positive contactor F1, the negative electrode of the battery pack 120 is connected to the front end of the negative contactor F2, the rear end LINK+ of the positive contactor F1 is connected to one end of the high-voltage discharge port 130, and the other end of the high-voltage discharge port 130 is connected to the rear end LINK- of the negative contactor F2. The first switch Q1 is arranged between the front end PACK+ of the positive contactor F1 and the front end of the negative contactor F2, and the second switch Q2 is arranged between the rear end LINK+ of the positive contactor F1 and the rear end LINK- of the negative contactor F2. The controller 110 realizes the switching of the detection mode by controlling the on-off state of the first switch Q1 and the second switch Q2.

[0123] Each low-voltage acquisition unit includes two voltage-dividing resistors connected in series, and the first voltage-dividing resistor R1 and the second voltage-dividing resistor R2 constitute a voltage-dividing circuit of the first channel, wherein one end of the first voltage-dividing resistor R1 is connected to one end of the second voltage-dividing resistor R2, the other end of the first voltage-dividing resistor R1 is connected to the front end PACK+ of the positive contactor F1, and the other end of the second voltage-dividing resistor R2 is connected to the front end of the negative contactor F2.

[0124] Similarly, the third voltage-dividing resistor R3 and the fourth voltage-dividing resistor R4 constitute a voltage-dividing circuit of the second channel, one end of the third voltage-dividing resistor R3 is connected to one end of the fourth voltage-dividing resistor R4, the other end of the third voltage-dividing resistor R3 is connected to the rear end LINK+ of the positive contactor F1, and the other end of the fourth voltage-dividing resistor R4 is connected to the rear end of the negative contactor F2 through the second switch Q2.

[0125] One end of the fifth voltage-dividing resistor R5 is connected to one end of the sixth voltage-dividing resistor R6, the other end of the fifth voltage-dividing resistor R5 is connected to the rear end DC+ of the fast charging positive contactor F3, and the other end of the sixth voltage-dividing resistor R6 is grounded; one end of the ninth voltage-dividing resistor R9 is connected to one end of the tenth voltage-dividing resistor R10, the ninth voltage-dividing resistor R9 is connected to the second preset power supply VREF2, and the other end of the tenth voltage-dividing resistor R10 is connected to the rear end DC- of the fast charging negative contactor F4, thus forming channels for multiple voltage-dividing circuits.

[0126] According to the channels of each voltage divider circuit, the voltage calculation unit can calculate the first voltage to the sixth voltage. The controller 110 controls the on-off state of the first switch Q1 and the second switch Q2, switches the detection mode accordingly, and detects the state of each contactor based on the obtained first voltage to the sixth voltage.

[0127] In general, the contactor state detection device of the embodiment of the present invention obtains the voltage corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, by setting the first high-voltage reference ground and the second high-voltage reference ground. The controller switches the detection mode according to the on-off state of the switch unit, so as to detect the positive and negative contactor states in the first detection mode and detect the fast-charging positive and negative contactors in the second detection mode, so that there is no requirement for the contactor action timing when performing contactor state detection, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the controller can control the detection device to switch to the second detection mode for fast charging. The status of the positive and negative contactors is detected. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the status detection of the fast charging positive and negative contactors is completed. They can be disconnected immediately and then switch to the corresponding detection mode to realize the status detection of the positive and negative contactors and the fast charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. In addition, by controlling the on and off states of the first switch and the second switch, it is possible to avoid the voltage acquisition circuit being directly connected between the positive and negative poles of the battery pack to form a discharge loop, thereby preventing the battery pack from being over-discharged. At the same time, one controller can be used to complete the detection of the contactor status, thereby reducing product costs.

[0128] A further embodiment of the present invention also discloses a contactor state detection method, which is used in the contactor state detection device described in any one of the above embodiments of the present invention. Figure 7-Figure 11 A contactor state detection method according to an embodiment of the present invention is described.

[0129] Figure 7 FIG. 1 is a flow chart of a contactor status detection method according to an embodiment of the present invention. Figure 7 As shown, the method comprises the following steps:

[0130] Step S1, obtain the first voltage to the sixth voltage, the first voltage is the voltage of the front end of the positive contactor relative to the first high voltage reference ground, the second voltage is the voltage of the rear end of the positive contactor relative to the first high voltage reference ground, the third voltage is the voltage of the rear end of the negative contactor relative to the first high voltage reference ground, the fourth voltage is the voltage of the rear end of the positive contactor relative to the second high voltage reference ground, the fifth voltage is the voltage of the rear end of the fast charging positive contactor relative to the second high voltage reference ground, and the sixth voltage is the voltage of the rear end of the fast charging negative contactor relative to the second high voltage reference ground, wherein the rear end of the positive contactor is connected to the front end of the fast charging positive contactor, and the front end of the fast charging negative contactor is connected to the rear end of the negative contactor.

[0131] Specifically, the first voltage to the sixth voltage can be obtained through the high-voltage acquisition chip ASIC, that is, it is necessary to measure the voltage of the front end of the positive contactor relative to the first high-voltage reference ground, the voltage of the rear end of the positive contactor relative to the first high-voltage reference ground, the voltage of the rear end of the negative contactor relative to the first high-voltage reference ground, the voltage of the rear end of the positive contactor relative to the second high-voltage reference ground, the voltage of the rear end of the fast-charging positive contactor relative to the second high-voltage reference ground, and the voltage of the rear end of the fast-charging negative contactor relative to the second high-voltage reference ground, so as to detect the contactor status based on these acquired voltages.

[0132] Step S2, controlling the on / off state of the switch unit to switch the detection device to a first detection mode or a second detection mode, wherein in the first detection mode, the front end of the negative pole contactor is used as a first high-voltage reference ground, and in the second detection mode, the front end of the fast-charging negative pole contactor is used as a second high-voltage reference ground.

[0133] Specifically, controlling the on-off state of the switch unit can switch the detection mode. When the switch unit is in a specific on-off state, the detection device can be switched to the first detection mode. At this time, the front end of the negative contactor is the first high-voltage reference ground. When the switch unit is in another specific on-off state, the detection device can be switched to the second detection mode. At this time, the front end of the fast-charging negative contactor is the second high-voltage reference ground. By setting the corresponding high-voltage reference ground, the detection of the positive and negative contactors and the fast-charging positive and negative contactors can be realized.

[0134] Step S3, when switching to the first detection mode, the status of the positive contactor and the negative contactor is determined according to the first voltage, the second voltage, the third voltage and the first preset reference voltage, and / or, when switching to the second detection mode, the status of the fast charging positive contactor and the fast charging negative contactor is determined according to the fourth voltage, the fifth voltage, the sixth voltage and the second preset reference voltage.

[0135] Specifically, when the detection device is switched to the first detection mode, the states of the positive contactor and the negative contactor can be determined by comparing and analyzing the first voltage, the second voltage, the third voltage and the first preset reference voltage. Similarly, when the detection device is switched to the second detection mode, the states of the fast charging positive contactor and the fast charging negative contactor can be determined by comparing and analyzing the fourth voltage, the fifth voltage, the sixth voltage and the second preset reference voltage. This solves the problem of requiring the contactor action timing when performing contactor status detection and shortens the power-off time.

[0136] According to the contactor state detection method of the embodiment of the present invention, by setting the first high-voltage reference ground and the second high-voltage reference ground, and obtaining the voltages corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, and then switching the detection mode according to the on-off state of the switch unit, the positive and negative contactor states are detected in the first detection mode, and the fast charging positive and negative contactors are detected in the second detection mode, so that there is no requirement for the contactor action timing when performing contactor state detection, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the detection device can be controlled to switch to the second detection mode to detect the states of the fast charging positive and negative contactors. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the fast charging positive and negative contactors is completed. They can be disconnected immediately and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, one controller can be used to complete the contactor state detection, thereby reducing product cost.

[0137] In one embodiment of the present invention, in the first detection mode, the state of the positive contactor is determined according to the first voltage and the second voltage, and the state of the negative contactor is determined according to the third voltage and the first preset reference voltage.

[0138] In one embodiment of the present invention, when the absolute value of the difference between the first voltage and the second voltage is less than a first set threshold, it is determined that the positive contactor is in a closed state; otherwise, it is determined that the positive contactor is in an open state.

[0139] Specifically, refer to Figure 8 As shown, it is a flowchart of positive contactor status detection, and the process includes steps S11 to S17.

[0140] Step S11, start.

[0141] Step S12: the detection device switches to the first detection mode.

[0142] Step S13, determining the state of the positive contactor according to the first voltage and the second voltage.

[0143] Step S14, determining whether the absolute value of the difference between the first voltage and the second voltage is less than a first set threshold value, if so, executing step S15; if not, executing step S16.

[0144] Step S15, determining whether the positive contactor is in a closed state.

[0145] Step S16, determining whether the positive contactor is in an open state.

[0146] Step S17, end.

[0147] In one embodiment of the present invention, when the absolute value of the difference between the third voltage and the first preset reference voltage is less than the second set threshold, it is determined that the negative contactor is in an open state; otherwise, it is determined that the negative contactor is in a closed state.

[0148] Specifically, refer to Fig. 9 As shown, it is a flowchart of negative contactor status detection, and the process includes steps S21 to S27.

[0149] Step S21, start.

[0150] Step S22: the detection device switches to the first detection mode.

[0151] Step S23, determining the state of the negative contactor according to the third voltage and the first preset reference voltage.

[0152] Step S24, determining whether the absolute value of the difference between the third voltage and the first preset reference voltage is less than a second set threshold value, if so, executing step S25; if not, executing step S26.

[0153] Step S25, determining whether the negative electrode contactor is in a closed state.

[0154] Step S26, determining whether the negative electrode contactor is in an open state.

[0155] Step S27, end.

[0156] In one embodiment of the present invention, in the second detection mode, the state of the fast charging positive contactor is determined according to the fourth voltage and the fifth voltage, and the state of the fast charging negative contactor is determined according to the sixth voltage and the second preset reference voltage.

[0157] In one embodiment of the present invention, when the absolute value of the difference between the fourth voltage and the fifth voltage is less than the third set threshold, it is determined that the fast charging positive contactor is in a closed state, otherwise, it is determined that the fast charging positive contactor is in a disconnected state.

[0158] Specifically, refer to Fig.10As shown, it is a flowchart of the fast charging positive contactor status detection, and the process includes steps S31 to S37.

[0159] Step S31, start.

[0160] Step S32: the detection device switches to the second detection mode.

[0161] Step S33, determining the state of the fast charging positive contactor according to the fourth voltage and the fifth voltage.

[0162] Step S34, determining whether the absolute value of the difference between the fourth voltage and the fifth voltage is less than a third set threshold value, if so, executing step S35; if not, executing step S36.

[0163] Step S35, determining whether the fast charging positive contactor is in a closed state.

[0164] Step S36, determining whether the fast charging positive contactor is in the disconnected state.

[0165] Step S37, end.

[0166] In one embodiment of the present invention, when the absolute value of the difference between the sixth voltage and the second preset reference voltage is less than the fourth set threshold, it is determined that the fast charging negative pole contactor is in an open state, otherwise, it is determined that the fast charging negative pole contactor is in a closed state.

[0167] Specifically, refer to Fig.11 As shown, it is a flowchart of the fast charging negative electrode contactor status detection, and the process includes steps S41 to S47.

[0168] Step S41, start.

[0169] Step S42: the detection device switches to the second detection mode.

[0170] Step S43, determining the state of the fast charging negative electrode contactor according to the sixth voltage and the second preset reference voltage.

[0171] Step S44, determining whether the absolute value of the difference between the sixth voltage and the second preset reference voltage is less than a fourth set threshold value, if so, executing step S45; if not, executing step S46.

[0172] Step S45, determining whether the fast charging negative electrode contactor is in a closed state.

[0173] Step S46, determining whether the fast charging negative electrode contactor is in the disconnected state.

[0174] Step S47, end.

[0175] In one embodiment of the present invention, the above-mentioned switching unit includes: a first switch and a second switch, the first switch is arranged between the front end of the positive contactor and the front end of the negative contactor; the second switch is arranged between the rear end of the positive contactor and the rear end of the negative contactor; when the controller controls the first switch to be turned on and controls the second switch to be turned off, the detection device switches to the first detection mode; when the controller controls the first switch to be turned off and controls the second switch to be turned on, the detection device switches to the second detection mode.

[0176] In one embodiment of the present invention, the contactor state detection method further includes: a preset power supply provides a first preset reference voltage and a second preset reference voltage.

[0177] In one embodiment of the present invention, the preset power supply includes: a first preset power supply and a second preset power supply, wherein the first preset power supply provides a first preset reference voltage; and the second preset power supply provides a second preset reference voltage.

[0178] In one embodiment of the present invention, the contactor status detection method also includes: collecting voltages from the first channel to the fifth channel, wherein the two ends of the first channel are the front end of the positive contactor and the front end of the negative contactor, respectively, the two ends of the second channel are the rear end of the positive contactor and the front end of the negative contactor, respectively, the two ends of the third channel are the rear end of the fast charging positive contactor and the front end of the fast charging negative contactor, respectively, the two ends of the fourth channel are the first preset power supply and the rear end of the negative contactor, respectively, and the two ends of the fifth channel are the second preset power supply and the rear end of the fast charging negative contactor, respectively; calculating the first voltage according to the voltage of the first channel, and calculating the second voltage according to the voltage of the second channel, and calculating the third voltage according to the voltage of the fourth channel, and calculating the fourth voltage according to the voltage of the second channel, and calculating the fifth voltage according to the voltage of the third channel, and calculating the sixth voltage according to the voltage of the fifth channel.

[0179] According to the contactor state detection method of the embodiment of the present invention, by setting the first high-voltage reference ground and the second high-voltage reference ground, and obtaining the voltages corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, and then switching the detection mode according to the on-off state of the switch unit, the positive and negative contactor states are detected in the first detection mode, and the fast charging positive and negative contactors are detected in the second detection mode, so that there is no requirement for the contactor action timing when performing contactor state detection, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the detection device can be controlled to switch to the second detection mode to detect the states of the fast charging positive and negative contactors. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the fast charging positive and negative contactors is completed. The positive and negative contactors can be disconnected immediately, and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, one controller can be used to complete the detection of the contactor state, thereby reducing product cost.

[0180] A further embodiment of the present invention also discloses a battery system, which includes the contactor state detection device described in any one of the above embodiments of the present invention.

[0181] According to the battery system of the embodiment of the present invention, by setting the first high-voltage reference ground and the second high-voltage reference ground, and obtaining the voltages corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, the detection mode is switched according to the on-off state of the switch unit, so as to detect the state of the positive and negative contactors in the first detection mode, and detect the fast-charging positive and negative contactors in the second detection mode, so that there is no requirement for the contactor action timing when detecting the contactor state, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the detection device can be controlled to switch to the second detection mode to detect the state of the fast-charging positive and negative contactors. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the fast-charging positive and negative contactors is completed. They can be disconnected immediately and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast-charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, one controller can be used to complete the detection of the contactor state, thereby reducing the product cost.

[0182] A further embodiment of the present invention discloses an electric vehicle, which includes the battery system described in any one of the above embodiments of the present invention.

[0183] According to the electric vehicle of the embodiment of the present invention, by setting the first high-voltage reference ground and the second high-voltage reference ground, and obtaining the voltages corresponding to each high-voltage reference ground, that is, the first voltage to the sixth voltage, the detection mode is switched according to the on-off state of the switch unit, so as to detect the state of the positive and negative contactors in the first detection mode, and detect the positive and negative contactors of the fast charging in the second detection mode, so that there is no requirement for the contactor action timing when the contactor state detection is performed, and when the whole vehicle is in a low-voltage state and the positive and negative contactors are disconnected, the detection device can be controlled to switch to the second detection mode to detect the state of the positive and negative contactors of the fast charging. In addition, after charging is completed, there is no need to disconnect the positive and negative contactors after the state detection of the positive and negative contactors of the fast charging is completed. The positive and negative contactors can be disconnected immediately and then the corresponding detection mode is switched to realize the state detection of the positive and negative contactors and the fast charging positive and negative contactors in the corresponding detection mode, thereby shortening the power-off time. At the same time, a controller can be used to complete the detection of the contactor state, thereby reducing the product cost.

[0184] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0185] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A contactor state detection device, characterized in that: include: A switch unit, the switch unit is used to switch the detection device to a first detection mode or a second detection mode through its own on-off state, wherein in the first detection mode, the front end of the negative contactor is used as the first high-voltage reference ground, and in the second detection mode, the front end of the fast-charge negative contactor is used as the second high-voltage reference ground; A controller, the controller is connected to the switch unit, and is used to obtain a first voltage to a sixth voltage, the first voltage is the voltage of the front end of the positive contactor relative to the first high-voltage reference ground, the second voltage is the voltage of the rear end of the positive contactor relative to the first high-voltage reference ground, the third voltage is the voltage of the rear end of the negative contactor relative to the first high-voltage reference ground, the fourth voltage is the voltage of the rear end of the positive contactor relative to the second high-voltage reference ground, the fifth voltage is the voltage of the rear end of the fast-charging positive contactor relative to the second high-voltage reference ground, and the sixth voltage is the voltage of the rear end of the fast-charging negative contactor relative to the second high-voltage reference ground, wherein the rear end of the positive contactor is connected to the front end of the fast-charging positive contactor, and the front end of the fast-charging negative contactor is connected to the rear end of the negative contactor; The controller is also used to control the on and off state of the switch unit to switch the detection mode, and when switching to the first detection mode, the state of the positive contactor and the negative contactor is judged according to the first voltage, the second voltage, the third voltage and the first preset reference voltage, and / or, when switching to the second detection mode, the state of the fast charging positive contactor and the fast charging negative contactor is judged according to the fourth voltage, the fifth voltage, the sixth voltage and the second preset reference voltage.

2. The contactor state detection device according to claim 1, characterized in that: The switch unit comprises: A first switch, the first switch is arranged between a front end of the positive contactor and a front end of the negative contactor; a second switch, the second switch being disposed between a rear end of the positive contactor and a rear end of the negative contactor; When the controller controls the first switch to be turned on and controls the second switch to be turned off, the detection device switches to the first detection mode; When the controller controls the first switch to be turned off and controls the second switch to be turned on, the detection device switches to the second detection mode.

3. The contactor state detection device according to claim 1, characterized in that: Also includes: A preset power supply is used to provide the first preset reference voltage and the second preset reference voltage.

4. The contactor state detection device according to claim 3, characterized in that: The preset power supply includes: A first preset power supply, wherein the first preset power supply is used to provide the first preset reference voltage; A second preset power source, wherein the second preset power source is used to provide the second preset reference voltage.

5. The contactor state detection device according to claim 4, characterized in that: Also includes: A voltage collection unit, the voltage collection unit is used to collect voltages from the first channel to the fifth channel, wherein the two ends of the first channel are respectively the front end of the positive contactor and the front end of the negative contactor, the two ends of the second channel are respectively the rear end of the positive contactor and the front end of the negative contactor, the two ends of the third channel are respectively the rear end of the fast charging positive contactor and the front end of the fast charging negative contactor, the two ends of the fourth channel are respectively the first preset power supply and the rear end of the negative contactor, and the two ends of the fifth channel are respectively the second preset power supply and the rear end of the fast charging negative contactor; a voltage calculation unit, configured to calculate the first voltage according to the voltage of the first channel, calculate the second voltage according to the voltage of the second channel, calculate the third voltage according to the voltage of the fourth channel, calculate the fourth voltage according to the voltage of the second channel, calculate the fifth voltage according to the voltage of the third channel, and calculate the sixth voltage according to the voltage of the fifth channel; The voltage calculation unit is further used to input the first voltage to the sixth voltage into the controller.

6. The contactor state detection device according to claim 4, characterized in that: Also includes: A voltage collection unit, the voltage collection unit is used to collect voltages from the first channel to the fifth channel, wherein the two ends of the first channel are respectively the front end of the positive contactor and the front end of the negative contactor, the two ends of the second channel are respectively the rear end of the positive contactor and the front end of the negative contactor, the two ends of the third channel are respectively the rear end of the fast charging positive contactor and the front end of the fast charging negative contactor, the two ends of the fourth channel are respectively the first preset power supply and the rear end of the negative contactor, and the two ends of the fifth channel are respectively the second preset power supply and the rear end of the fast charging negative contactor; The controller is specifically used to calculate the first voltage according to the voltage of the first channel, and calculate the second voltage according to the voltage of the second channel, and calculate the third voltage according to the voltage of the fourth channel, and calculate the fourth voltage according to the voltage of the second channel, and calculate the fifth voltage according to the voltage of the third channel, and calculate the sixth voltage according to the voltage of the fifth channel.

7. The contactor state detection device according to claim 5 or 6, characterized in that: The voltage acquisition unit comprises: A first voltage acquisition unit, wherein the first voltage acquisition unit is connected between a front end of the positive contactor and a front end of the negative contactor; A second voltage collection unit, wherein the second voltage collection unit is connected between a rear end of the positive contactor and a front end of the negative contactor; A third voltage collection unit, the third voltage collection unit is connected between the rear end of the fast charging positive contactor and the front end of the fast charging negative contactor; a fourth voltage acquisition unit, the fourth voltage acquisition unit being connected between the first preset power source and a rear end of the negative contactor; A fifth voltage collection unit, wherein the fifth voltage collection unit is connected between the second preset power supply and the rear end of the fast charging negative electrode contactor.

8. The contactor state detection device according to claim 7, characterized in that: The first voltage acquisition unit to the fifth voltage acquisition unit respectively include at least two voltage dividing resistors connected in series.

9. The contactor state detection device according to claim 1, characterized in that: In the first detection mode, the controller determines the state of the positive contactor according to the first voltage and the second voltage, and the controller determines the state of the negative contactor according to the third voltage and the first preset reference voltage.

10. The contactor state detection device according to claim 9, characterized in that: The controller is used to: When the absolute value of the difference between the first voltage and the second voltage is less than a first set threshold, it is determined that the positive contactor is in a closed state; otherwise, it is determined that the positive contactor is in an open state.

11. The contactor state detection device according to claim 9, characterized in that: The controller is used to: When the absolute value of the difference between the third voltage and the first preset reference voltage is less than a second set threshold, it is determined that the negative contactor is in an open state; otherwise, it is determined that the negative contactor is in a closed state.

12. The contactor state detection device according to claim 1, characterized in that: In the second detection mode, the controller determines the state of the fast charging positive contactor based on the fourth voltage and the fifth voltage, and the controller determines the state of the fast charging negative contactor based on the sixth voltage and the second preset reference voltage.

13. The contactor state detection device according to claim 12, characterized in that: The controller is used to: When the absolute value of the difference between the fourth voltage and the fifth voltage is less than the third set threshold, it is determined that the fast charging positive contactor is in a closed state; otherwise, it is determined that the fast charging positive contactor is in a disconnected state.

14. The contactor state detection device according to claim 13, characterized in that: The controller is used to: When the absolute value of the difference between the sixth voltage and the second preset reference voltage is less than a fourth set threshold, it is determined that the fast charging negative electrode contactor is in an open state; otherwise, it is determined that the fast charging negative electrode contactor is in a closed state.

15. A contactor state detection method, characterized in that: For use in a contactor state detection device according to any one of claims 1 to 14, the detection method comprises: Obtain the first voltage to the sixth voltage, the first voltage is the voltage of the front end of the positive contactor relative to the first high-voltage reference ground, the second voltage is the voltage of the rear end of the positive contactor relative to the first high-voltage reference ground, the third voltage is the voltage of the rear end of the negative contactor relative to the first high-voltage reference ground, the fourth voltage is the voltage of the rear end of the positive contactor relative to the second high-voltage reference ground, the fifth voltage is the voltage of the rear end of the fast-charging positive contactor relative to the second high-voltage reference ground, and the sixth voltage is the voltage of the rear end of the fast-charging negative contactor relative to the second high-voltage reference ground, wherein the rear end of the positive contactor is connected to the front end of the fast-charging positive contactor, and the front end of the fast-charging negative contactor is connected to the rear end of the negative contactor; Controlling the on / off state of the switch unit to switch the detection device to a first detection mode or a second detection mode, wherein in the first detection mode, the front end of the negative electrode contactor is used as the first high-voltage reference ground, and in the second detection mode, the front end of the fast-charging negative electrode contactor is used as the second high-voltage reference ground; When switching to the first detection mode, the states of the positive contactor and the negative contactor are determined according to the first voltage, the second voltage, the third voltage and the first preset reference voltage, and / or, when switching to the second detection mode, the states of the fast charging positive contactor and the fast charging negative contactor are determined according to the fourth voltage, the fifth voltage, the sixth voltage and the second preset reference voltage.

16. A battery system, characterized in that: It comprises a contactor state detection device as described in any one of claims 1 to 14.

17. An electric vehicle, characterized in that: Comprising the battery system as claimed in claim 16.

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