State detection circuit and charging pile

Abstract

The utility model provides a state detection circuit and a charging pile. Under the condition that the to-be-detected relay is disconnected, because the two ends of the to-be-detected relay are not connected and one end of the to-be-detected relay is connected with the output end of the external power supply, the potentials of the two ends of the to-be-detected relay are different, so that current flows through a series branch formed by all the first resistor branches; in this case, the potential of the output end of the state detection circuit is large. Under the condition that the to-be-detected relay is closed, because the two ends of the to-be-detected relay are connected, the potentials of the two ends of the to-be-detected relay are approximately the same, so that approximately no current flows through the series branch, and the potential of the output end of the state detection circuit is relatively small under the condition; in conclusion, the state detection circuit can be used for detecting the state of the relay to be detected, and since the external power supply is used, the state detection circuit is not influenced by electrification of the positive electrode of a device on one side of the relay to be detected, so that the possibility of errors during state detection of the relay is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of state detection, in particular to a state detection circuit and a charging pile. Background Art

[0002] At present, the main function of a relay is to connect or disconnect the connection between the devices on both sides of itself. Therefore, if the state of the relay cannot be known, protective measures cannot be taken in time when the state of the relay is abnormal, which may damage the devices on both sides of the relay.

[0003] Generally, the mainstream state diagnosis scheme of a relay is the resistance voltage division scheme. However, if the positive pole of the device on one side of the relay is charged, it will affect the resistance voltage division scheme, resulting in possible errors in the state detection of the relay, that is, misdiagnosis occurs.

[0004] Therefore, how to reduce the possibility of errors in the state detection of the relay is a technical problem to be solved urgently. Summary of the Utility Model

[0005] In view of this, the utility model provides a state detection circuit and a charging pile to reduce the possibility of errors in the state detection of the relay.

[0006] To achieve the above object, the embodiments of the utility model provide the following technical solutions:

[0007] On the one hand, the present application provides a state detection circuit, including: an external power supply and at least two first resistor branches; wherein:

[0008] All the first resistor branches are connected in series, and both ends of the formed series branch are connected to both ends of the relay to be detected;

[0009] The output end of the external power supply is connected to any one end of the relay to be detected;

[0010] The connection point of any two of the first resistor branches is used as the output end of the state detection circuit.

[0011] Optionally, it further includes: a second resistor branch; wherein:

[0012] One end of the second resistor branch is connected to the output end of the external power supply, and the other end of the second resistor branch is connected to one end of the state detection circuit.

[0013] Optionally, it further includes: a first switching device and a switch driving circuit; wherein:

[0014] The first switching device is connected in series with all the first resistor branches;

[0015] The control terminal of the first switching device is connected to the output terminal of the switching drive circuit, and the input terminal of the switching drive circuit receives a first conduction signal, which is a signal issued when there is a need to detect the state of the relay to be detected.

[0016] Optionally, if the first switching device is a MOS transistor, the switching drive circuit includes: a third resistor branch and a fourth resistor branch; where:

[0017] The gate of the first switching device is connected to one end of the third resistor branch;

[0018] If the source of the first switching device is connected to the first resistor branch, the source of the first switching device is connected to the other end of the third resistor branch through the first resistor branch connected thereto;

[0019] If the source of the first switching device is not connected to the first resistor branch, the source of the first switching device is connected to the other end of the third resistor branch;

[0020] The gate of the first switching device is further connected to one end of the fourth resistor branch, and the other end of the fourth resistor branch receives the first conduction signal.

[0021] Optionally, it further includes: a first diode branch; where:

[0022] The anode of the first diode branch is connected to the output terminal of the external power supply, and the cathode of the first diode branch is connected to one end of the relay to be detected.

[0023] On the one hand, the present application provides a charging pile, including: a power conversion device, a controller, at least one drive control circuit, at least one relay, and at least one state detection circuit as described in any one of the foregoing aspects of the present application; where:

[0024] Each of the relays serves as the relay to be detected of the state detection circuit corresponding to itself;

[0025] The output terminal of each of the drive control circuits is connected to the coil in the corresponding relay of itself;

[0026] Between the positive pole of the DC side of the power conversion device and the positive pole of the battery pack in the vehicle, at least one of the relays is connected in series;

[0027] And / or,

[0028] Between the negative pole of the DC side of the power conversion device and the negative pole of the battery pack in the vehicle, at least one of the relays is connected in series.

[0029] Optionally, it further includes: at least one drive state detection circuit; wherein:

[0030] Each of the drive control circuits serves as a detection object of the drive state detection circuit corresponding to itself.

[0031] Optionally, the drive state detection circuit includes: a second diode branch and at least two fifth resistor branches; wherein:

[0032] All the fifth resistor branches are connected in series. One end of the formed series branch is connected to the output end of the power supply, and the other end of the formed series branch is connected to any pole of the output end of the drive control circuit corresponding to the drive state detection circuit.

[0033] The cathode of the second diode branch is connected to the connection point of any two of the fifth resistor branches, and the anode of the second diode branch serves as the output end of the drive state detection circuit.

[0034] Or,

[0035] The cathode of the second diode branch is connected to the drive circuit of the relay through at least one of the fifth resistor branches, the anode of the second diode branch is connected to the output end of the first power supply through at least one of the fifth resistor branches, and the anode of the second diode branch serves as the output end of the drive state detection circuit.

[0036] Optionally, the drive state detection circuit further includes: a sixth resistor branch; wherein:

[0037] One end of the sixth resistor branch is connected to the connection point of any two of the fifth resistor branches, and the other end of the sixth resistor branch serves as the output end of the drive state detection circuit.

[0038] Optionally, the power conversion device includes a DC / DC conversion device or a DC / AC conversion device.

[0039] As can be seen from the above technical solution, the present utility model provides a state detection circuit. When the relay to be detected is disconnected, since the two ends of the relay to be detected are not connected, and one end of the relay to be detected is connected to the output end of the external power supply, the potentials at the two ends of the relay to be detected are not the same, that is, the potentials at the two ends of the series branch formed by all the first resistor branches are not the same, so there is a current flowing through the series branch formed by all the first resistor branches. Furthermore, when the relay to be detected is disconnected, the potential at the output end of the state detection circuit is relatively high; when the relay to be detected is attracted, since the two ends of the relay to be detected are connected, the potentials at the two ends of the relay to be detected are approximately the same, that is, the potentials at the two ends of the series branch formed by all the first resistor branches are approximately the same, so there is approximately no current flowing through the series branch formed by all the first resistor branches. Furthermore, when the relay to be detected is attracted, the potential at the output end of the state detection circuit is relatively low; as can be seen from the above, according to the potential at the output end of the state detection circuit, the state detection of the relay to be detected can be realized; and since the external power supply is used in this state detection circuit and the voltage difference between the two poles of the devices on both sides of the relay to be detected is not utilized, that is, it will not be affected by the positive charging of the device on one side of the relay to be detected, the possibility of error in the state detection of the relay to be detected is reduced. Brief Description of the Drawings

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0041] Figures 1 - 6 They are respectively the structural schematic diagrams of six implementation manners of the charging pile provided by the embodiments of the present application;

[0042] Figure 7 It is the structural schematic diagram of an implementation manner of the drive control circuit provided by the embodiment of the present application;

[0043] Figure 8 It is the connection schematic diagram between an implementation manner of the drive state detection circuit 500 provided by the embodiment of the present application and the drive control circuit 300;

[0044] Figure 9 It is the connection schematic diagram between another implementation manner of the drive state detection circuit 500 provided by the embodiment of the present application and the drive control circuit 300. Detailed Description of the Embodiments

[0045] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present application.

[0046] In the present application, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the phrase "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the element.

[0047] In order to reduce the possibility of errors occurring during the state detection of a relay, the present application provides a state detection circuit, and its specific structure can be seen in Figure 1 or Figure 2 , specifically including: an external power supply 10 and at least two first resistor branches 20.

[0048] All the first resistor branches 20 are connected in series, and both ends of the formed series branch are respectively connected to both ends of the relay to be detected, and the connection point of any two first resistor branches 20 is used as the output end of the state detection circuit; for example, as Figure 1 or shown in Figure 2, taking two first resistor branches 20 as an example, both ends of the series branch formed by connecting the two first resistor branches 20 in series are respectively connected to both ends of the relay 100, and the connection point of the two first resistor branches 20 is used as the output end of the state detection circuit.

[0049] Among them, the first resistor branch 20 includes at least one resistor. If the number of resistors is greater than 1, each resistor is connected in series and parallel, and both ends of the formed branch are respectively used as both ends of the first resistor branch 20; if the number of resistors is equal to 1, both ends of the resistor are respectively used as both ends of the first resistor branch 20; for example, as Figure 1 or Figure 2 the R1 shown in.

[0050] The output end of the external power supply 10 is connected to any one end of the relay to be detected. For example, as Figure 1 shown, the output end of the external power supply 10 is connected to the right end of the relay 100; and for another example, asFigure 2 As shown, the output terminal of the external power supply 10 is connected to the left end of the relay 100; usually, the output voltage of the external power supply 10 can be 15V.

[0051] As can be seen from the above, the potentials at both ends of the series branch formed by all the first resistor branches 20 are the potentials at both ends of the relay to be detected; for example, Figure 1 taking [example] as an example, the potentials at both ends of the series branch formed by two first resistor branches 20 are the potentials at both ends of the relay 100.

[0052] When the relay to be detected is open, since the two ends of the relay to be detected are not connected, and one end of the relay to be detected is connected to the output terminal of the external power supply 10, the potentials at both ends of the relay to be detected are not the same, that is, the potentials at both ends of the series branch formed by all the first resistor branches 20 are not the same, so there is current flowing through the series branch formed by all the first resistor branches 20, and then when the relay to be detected is open, the potential at the output terminal of the state detection circuit is relatively large; usually, Figure 1 taking [example] as an example, when the relay 100 is open, the potential at the output terminal of the state detection circuit is between 2V and 5V.

[0053] When the relay to be detected is closed, since the two ends of the relay to be detected are connected, the potentials at both ends of the relay to be detected are approximately the same, that is, the potentials at both ends of the series branch formed by all the first resistor branches 20 are approximately the same, so there is approximately no current flowing through the series branch formed by all the first resistor branches 20, and then when the relay to be detected is closed, the potential at the output terminal of the state detection circuit is relatively small; taking Figure 1 taking [example] as an example, when the relay 100 is closed, the potential at the output terminal of the state detection circuit is between 0V and 2V.

[0054] As can be seen from the above, according to the potential at the output terminal of the state detection circuit, the state detection of the relay to be detected can be realized.

[0055] Usually, the relay receives a second conduction signal through a drive control circuit. The second conduction signal is a signal sent when there is a need to control the relay to close. In other words, when there is a need to control the relay to close, the relay receives the second conduction signal through the drive control circuit; in addition, when the relay receives the second conduction signal through the drive control circuit, the relay closes.

[0056] Combining the second conduction signal and the potential at the output terminal of the state detection circuit, the state of the relay is determined as shown in the following table:

[0057]

[0058] Among them, 0 in the first column represents that the drive control circuit has not received the second conduction signal, and 1 in the first column represents that the drive control circuit has received the second conduction signal; 0 in the second column represents that the potential of the output terminal of the status detection circuit is relatively small; 1 in the second column represents that the potential of the output terminal of the status detection circuit is relatively large.

[0059] Since the status detection circuit uses an external power supply 10 and does not utilize the voltage difference between the two poles of the devices on both sides of the relay to be detected, that is, it will not be affected by the positive pole of the device on one side of the relay to be detected, the possibility of error in detecting the status of the relay to be detected is reduced.

[0060] Another embodiment of the present application provides another implementation manner of the status detection circuit, and its specific structure can be referred to Figure 3 , on the basis of the above implementation manner, this implementation manner further includes: a second resistor branch 30.

[0061] One end of the second resistor branch 30 is connected to the output terminal of the external power supply 10, and the other end of the second resistor branch 30 is connected to any end of the relay to be detected. For example, as Figure 3 shown, the other end of the second resistor branch 30 is connected to the right end of the relay 100.

[0062] Among them, the second resistor branch 30 includes at least one resistor. If the number of resistors is greater than 1, each resistor is connected in series and parallel, and the two ends of the formed branch are respectively used as the two ends of the second resistor branch 30; if the number of resistors is equal to 1, the two ends of the resistor are respectively used as the two ends of the second resistor branch 30; for example, as Figure 3 R2 shown in

[0063] In this implementation manner, adding the second resistor branch 30 can not only share the voltage with all the first resistor branches 20 when the relay to be detected is disconnected, but also limit the current output by the external power supply 10 when the relay to be detected is attracted, that is, avoid the current output by the external power supply 10 from being too large, so as to protect the external power supply 10.

[0064] This embodiment also provides another implementation manner of the status detection circuit, and its specific structure can be referred to Figure 4 , on the basis of the above implementation manner, this implementation manner further includes: a first switching device 40 and a switch driving circuit 50.

[0065] The first switching device 40 is connected in series with all the first resistor branches 20. For example, as Figure 4 shown, the first switching device 40 is connected in series with two first resistor branches 20.

[0066] The control terminal of the first switching device 40 is connected to the output terminal of the switching drive circuit 50. The input terminal of the switching drive circuit 50 receives a first conduction signal, which is a signal issued when there is a need to detect the state of the relay to be detected. In other words, when there is a need to detect the state of the relay to be detected, the switching drive circuit 50 receives the first conduction signal.

[0067] When the drive circuit 50 receives the first conduction signal, the first switching device 40 conducts. When the drive circuit 50 does not receive the first conduction signal, the first switching device 40 turns off.

[0068] Optionally, the first switching device 40 can be a MOS transistor. For example, as shown by Q1 in Figure 4 , it can also be an IGBT. In practical applications, including but not limited to this, it is not specifically limited here and can be determined according to specific circumstances, all within the protection scope of this application.

[0069] In this embodiment, by adding the first switching device 40 and the switching drive circuit 50, the state detection of the relay to be detected is controlled, that is, the relay to be detected can be detected only when there is a need to detect the state of the relay to be detected.

[0070] This embodiment of the present invention further provides another implementation manner of the state detection circuit. Its specific structure can be seen in Figure 5 , on the basis of the above embodiment, this embodiment further includes: a first diode branch 60.

[0071] The anode of the first diode branch 60 is connected to the output terminal of the external power supply 10, and the cathode of the first diode branch 60 is connected to one end of the relay to be detected. For example, as shown in Figure 5 , the cathode of the first diode branch 60 is connected to the right end of the relay 100.

[0072] Among them, the first diode branch 60 includes at least one diode. If the number of diodes is greater than 1, all diodes are connected in series in the same direction. The anode of the formed series branch is used as the anode of the first diode branch 60, and the cathode of the formed series branch is used as the cathode of the first diode branch 60. If the number of diodes is equal to 1, the anode of the diode is used as the anode of the first diode branch 60, and the cathode of the diode is used as the cathode of the first diode branch 60. For example, as shown by Z1 in Figure 5 .

[0073] In this embodiment, by adding the first diode branch 60, it is avoided that current flows into the external power supply 10, so the external power supply 10 can be protected.

[0074] The above are only three implementation manners of the status detection circuit, which are not specifically limited herein and may be determined according to specific situations, and all are within the protection scope of this application.

[0075] Another embodiment of this application provides an implementation manner of the switch driving circuit 50, which is applicable to the case where the first switching device 40 is a MOS transistor; for the specific structure of this implementation manner, reference may be made to Figure 6 , specifically including: a third resistor branch 51 and a fourth resistor branch 52.

[0076] The gate G of the first switching device 40 is connected to one end of the third resistor branch 51.

[0077] If a first resistor branch 20 is connected to the source S of the first switching device 40, as Figure 6 shown, then the source S of the first switching device 40 is connected to the other end of the third resistor branch 51 through the first resistor branch 20 connected thereto.

[0078] If a first resistor branch 20 is not connected to the source S of the first switching device 40, then the source S of the first switching device 40 is connected to the other end of the third resistor branch 51.

[0079] The gate G of the first switching device 40 is also connected to one end of the fourth resistor branch 52, and the other end of the fourth resistor branch 52 receives a first conduction signal.

[0080] Among them, the third resistor branch 51 includes at least one resistor. If the number of resistors is greater than 1, then each resistor is connected in series and parallel, and the two ends of the formed branch are respectively used as the two ends of the third resistor branch 51; if the number of resistors is equal to 1, then the two ends of the resistor are respectively used as the two ends of the third resistor branch 51; for example, as Figure 6 R3 shown in

[0081] Among them, the fourth resistor branch 52 includes at least one resistor. If the number of resistors is greater than 1, then each resistor is connected in series and parallel, and the two ends of the formed branch are respectively used as the two ends of the fourth resistor branch 52; if the number of resistors is equal to 1, then the two ends of the resistor are respectively used as the two ends of the fourth resistor branch 52; for example, as Figure 6 R4 shown in

[0082] The above is only one implementation manner of the switch driving circuit 50. In practical applications, it includes but is not limited to this. It is not specifically limited herein and may be determined according to specific situations, and all are within the protection scope of this application.

[0083] Another embodiment of this application provides a charging pile, and for its specific structure, reference may be made to Figures 1 - 6 , specifically including: a power conversion device, a controller, at least one drive control circuit, at least one relay, and at least one status detection circuit provided as in the above embodiment.

[0084] At least one relay is connected in series between the positive pole of the DC side of the power conversion device and the positive pole of the battery pack in the vehicle, and / or at least one relay is connected in series between the negative pole of the DC side of the power conversion device and the negative pole of the battery pack in the vehicle; for example, as Figures 1 - 6 shown, taking one relay 100 as an example, one relay 100 is connected in series between the negative pole of the DC side of the power conversion device and the negative pole of the battery pack in the vehicle.

[0085] Optionally, the power conversion device can be a DC / DC conversion device or a DC / AC conversion device, which is not specifically limited here and can be determined according to specific situations, and all are within the protection scope of this application.

[0086] Each relay serves as the relay to be detected by the state detection circuit corresponding to itself. In other words, each state detection circuit detects the state of the relay corresponding to itself.

[0087] As Figures 1 - 6 shown, each relay 100 includes a contact 101 and a coil 102.

[0088] Both ends of the contact 101 are used as the two ends of the relay 100; if the relay 100 is connected in series between the positive pole of the DC side of the power conversion device and the positive pole of the battery pack in the vehicle, the contact in the relay is connected in series between the positive pole of the DC side of the power conversion device and the positive pole of the battery pack in the vehicle; if the relay 100 is connected in series between the negative pole of the DC side of the power conversion device and the negative pole of the battery pack in the vehicle, the contact in the relay 100 is connected in series between the negative pole of the DC side of the power conversion device and the negative pole of the battery pack in the vehicle.

[0089] Both poles of the coil 102 are connected to the output end of the corresponding drive control circuit, that is, the output end of each drive control circuit is connected to the coil in the relay corresponding to itself.

[0090] For example, as Figures 1 - 6 shown, taking one relay 100 and one drive control circuit as an example for display, the coil 102 in the relay 100 is connected to the output end of the drive control circuit.

[0091] In a specific example, an implementation manner of the drive control circuit is given, and this implementation manner is applicable to each drive control circuit; the specific structure of this implementation manner is as Figure 7As shown in the figure, it specifically includes: a discharge circuit 310, a seventh resistor branch 320, and a second switching device 330; the input end of the second switching device 330 is connected to a second power supply 340 through a coil 102, and the output end of the second switching device 330 is grounded to GND; the control end of the second switching device 330 is connected to one end of the seventh resistor branch 320; the other end of the seventh resistor branch 320 serves as the input end of the drive control circuit and receives a second conduction signal. The second conduction signal is a signal sent when there is a need to control the relay to close. In other words, when there is a need to control the relay to close, the control end of the second switching device 330 receives the second conduction signal, that is, the input end of the drive control circuit 300 receives the second conduction signal.

[0092] It should be noted that the output voltage of the second power supply 340 can be set to 12V.

[0093] When the second switching device 330 receives the second conduction signal, the second switching device 330 conducts, so that the branch where the coil 102 is located is in a conducting state, that is, the coil 102 is powered on, so that the contact 101 of the relay 100 closes; when the second switching device 330 does not receive the second conduction signal, the second switching device 330 turns off, so that the branch where the coil 102 is located is in an open state, that is, the coil 102 loses power, so that the contact of the relay 102 does not close.

[0094] Optionally, the discharge circuit 310 can be a discharge diode, such as Figure 7 shown as D in the figure. In practical applications, including but not limited to this, specific limitations are not made here and can be determined according to specific situations, all within the protection scope of this application.

[0095] Optionally, the second switching device 330 can be a MOS transistor, for example, as Figure 7 shown as Q2 in the figure, or it can also be an IGBT. In practical applications, including but not limited to this, specific limitations are not made here and can be determined according to specific situations, all within the protection scope of this application.

[0096] Among them, the seventh resistor branch 320 includes at least one resistor. If the number of resistors is greater than 1, each resistor is connected in series and parallel, and the two ends of the formed branch are respectively used as the two ends of the seventh resistor branch 320; if the number of resistors is equal to 1, the two ends of the resistor are respectively used as the two ends of the seventh resistor branch 320; for example, as Figure 7 shown as R7 in the figure.

[0097] The above is only one implementation manner of the drive control circuit. In practical applications, including but not limited to this, specific limitations are not made here and can be determined according to specific situations, all within the protection scope of this application.

[0098] This embodiment also provides another implementation manner of the charging pile. On the basis of the above embodiment, it further includes: at least one driving state detection circuit.

[0099] Each drive control circuit serves as the detection object of the driving state detection circuit corresponding to itself. In other words, each driving state detection circuit performs state detection on the drive control circuit corresponding to itself; among them, performing state detection on the drive control circuit refers to: detecting the state of the switching device in the drive control circuit.

[0100] The above are only two implementation manners of the charging pile, which are not specifically limited here and can be determined according to specific situations, and are all within the protection scope of this application.

[0101] Another embodiment of this application provides an implementation manner of the driving state detection circuit 500, which is applicable to each driving state detection circuit 500; the specific structure of this embodiment is as Figure 8 shown, and specifically includes: a second diode branch 530 and at least two fifth resistor branches 510.

[0102] All the fifth resistor branches 510 are connected in series, and one end of the formed series branch is connected to the output end of the first power supply 520, and the other end of the formed series branch is connected to: any pole of the output end of the drive control circuit 300 corresponding to the driving state detection circuit.

[0103] For example, as Figure 8 shown, taking a relay 100, a drive control circuit 300, and a driving state detection circuit 500 as an example for display, two fifth resistor branches 510 are connected in series, one end of the formed series branch is connected to the output end of the first power supply 520, and the other end of the formed series branch is connected to: the A pole of the output end of the drive control circuit 300; the connection point of the two fifth resistor branches 510 serves as the output end of the driving state detection circuit 500.

[0104] Among them, the fifth resistor branch 510 includes at least one resistor. If the number of resistors is greater than 1, each resistor is connected in series and parallel, and the two ends of the formed branch are respectively used as the two ends of the fifth resistor branch 510; if the number of resistors is equal to 1, the two ends of the resistor are respectively used as the two ends of the fifth resistor branch 510; for example, as Figure 8 R5 shown in

[0105] In a specific example, the cathode of the second diode branch 530 is connected to the connection point of any two fifth resistor branches 510, and the anode of the second diode branch 530 serves as the output end of the driving state detection circuit.

[0106] In another specific example, the cathode of the second diode branch 530 is connected to either pole of the output terminal of the drive control circuit 300 corresponding to the drive state detection circuit 500 through at least one fifth resistor branch 510. The anode of the second diode branch 530 is connected to the output terminal of the first power supply 520 through at least one fifth resistor branch 510. The anode of the second diode branch 530 serves as the output terminal of the drive state detection circuit 500.

[0107] For example, as Figure 8 shown, taking two fifth resistor branches 510 as an example, the cathode of the second diode branch 530 is connected to the A pole of the output terminal of the drive control circuit 300 corresponding to the drive state detection circuit 500 through one fifth resistor branch 510. The anode of the second diode branch 530 is connected to the output terminal of the first power supply 520 through another fifth resistor branch 510. The anode of the second diode branch 530 serves as the output terminal of the drive state detection circuit 500.

[0108] Among them, the second diode branch 530 includes at least one diode. If the number of diodes is greater than 1, all the diodes are connected in series in the same direction. The anode of the formed series branch serves as the anode of the second diode branch 530, and the cathode of the formed series branch serves as the cathode of the second diode branch 530. If the number of diodes is equal to 1, the anode of the diode serves as the anode of the second diode branch 530, and the cathode of the diode serves as the cathode of the second diode branch 530. For example, as Figure 8 shown by Z2 in

[0109] Taking Figure 8 the drive control circuit 300 shown as an example, when the second switching device 330 is turned off, the branch formed by all the fifth resistor branches 510 and the second switching device 330 is in a short - circuit state. Therefore, the potential of the connection point of any two fifth resistor branches 510 is approximately equal to the output voltage of the first power supply 520, that is, the potential of the connection point of any two fifth resistor branches 510 is relatively large, so the potential of the output terminal of the drive state detection circuit 500 is relatively large.

[0110] Taking Figure 8 the drive control circuit 300 shown as an example, when the second switching device 330 is turned on, the branch formed by all the fifth resistor branches 510 and the second switching device 330 is in a conducting state. Therefore, the potential of the connection point of any two fifth resistor branches 510 is equal to the voltage division of some of the fifth resistor branches 510, that is, the potential of the connection point of any two fifth resistor branches 510 is relatively small, so the potential of the output terminal of the drive state detection circuit 500 is relatively small.

[0111] It can be seen therefrom that according to the potential at the output terminal of the drive state detection circuit 500, it can be determined whether the second switching device 330 is turned off or on, and thus the state of the drive control circuit 300 can be determined, that is, the state detection of the drive control circuit 300 is achieved.

[0112] Combining the second conduction signal and the potential at the output terminal of the drive state detection circuit 500, the state of the drive control circuit 300 is determined as shown in the following table:

[0113]

[0114] Among them, 0 in the first column represents that the drive control circuit 300 has not received the second conduction signal, and 1 in the first column represents that the drive control circuit 300 has received the second conduction signal; 0 in the second column represents that the potential at the output terminal of the drive state detection circuit 500 is small, and 1 in the second column represents that the potential at the output terminal of the drive state detection circuit 500 is large; taking Figure 8 the drive control circuit 300 shown as an example, the state of the drive control circuit 300 is normal, indicating that the second switching device 330 is normally turned off or on; taking Figure 8 the drive control circuit 300 shown as an example, the state of the drive control circuit 300 is abnormally disconnected, indicating that the second switching device 330 is abnormally disconnected; taking Figure 8 the drive control circuit 300 shown as an example, the state of the drive control circuit 300 is abnormally conductive, indicating that the second switching device 330 is abnormally conductive.

[0115] This embodiment also provides another implementation manner of the drive state detection circuit 500 for each drive state detection circuit 500; the specific structure of this implementation manner is as Figure 9 shown. On the basis of the above implementation manner, this implementation manner further includes: a sixth resistor branch 540.

[0116] One end of the sixth resistor branch 540 is connected to the connection point of any two fifth resistor branches 510, and the other end of the sixth resistor branch 540 serves as the output terminal of the drive state detection circuit 500.

[0117] As Figure 9 shown, taking two fifth resistor branches 510 as an example, one end of the sixth resistor branch 540 is connected to the connection point of the two fifth resistor branches 510, and the other end of the sixth resistor branch 540 serves as the output terminal of the drive state detection circuit.

[0118] Among them, the sixth resistor branch 540 includes at least one resistor. If the number of resistors is greater than 1, each resistor is connected in series and parallel, and the two ends of the formed branch serve as the two ends of the sixth resistor branch 540 respectively; if the number of resistors is equal to 1, the two ends of the resistor serve as the two ends of the sixth resistor branch 540 respectively; for example, asFigure 9 as shown by R6 in

[0119] The above are only three implementation manners of the driving state detection circuit 500. In actual applications, including but not limited to this, no specific limitation is made here and it can be determined according to specific situations, and all are within the protection scope of this application.

[0120] Regarding the above description of the disclosed embodiments, the features recorded in each embodiment in this specification can be mutually replaced or combined, enabling those skilled in the art to implement or use this application. The above are only preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent embodiment with equivalent changes, without departing from the scope of the technical solution of the present invention. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A state detection circuit, characterized in that, Including: An external power supply and at least two first resistor branches; wherein: All of the first resistor branches are connected in series, and both ends of the formed series branch are respectively connected to both ends of the relay to be tested; The output end of the external power supply is connected to any one end of the relay to be tested; The connection point of any two of the first resistor branches serves as the output end of the state detection circuit.

2. The state detection circuit according to claim 1, wherein Further including: A second resistor branch; wherein: One end of the second resistor branch is connected to the output end of the external power supply, and the other end of the second resistor branch is connected to one end of the state detection circuit.

3. The state detection circuit according to claim 1, wherein Further including: A first switching device and a switch driving circuit; wherein: The first switching device is connected in series with all of the first resistor branches; The control end of the first switching device is connected to the output end of the switch driving circuit, and the input end of the switch driving circuit receives a first conduction signal, and the first conduction signal is a signal sent when there is a need to detect the state of the relay to be tested.

4. The state detection circuit according to claim 3, wherein If the first switching device is a MOS transistor, then the switch driving circuit includes: a third resistor branch and a fourth resistor branch; wherein: The gate of the first switching device is connected to one end of the third resistor branch; If the source of the first switching device is connected to the first resistor branch, the source of the first switching device is connected to the other end of the third resistor branch through the first resistor branch to which it is connected; If the source of the first switching device is not connected to the first resistor branch, the source of the first switching device is connected to the other end of the third resistor branch; The gate of the first switching device is further connected to one end of the fourth resistor branch, and the other end of the fourth resistor branch receives the first conduction signal.

5. The state detection circuit according to any one of claims 1 to 4, characterized in that Further including: A first diode branch; wherein: The anode of the first diode branch is connected to the output end of the external power supply, and the cathode of the first diode branch is connected to one end of the relay to be tested.

6. A charging pile, characterized in that, Including: A power conversion device, a controller, at least one drive control circuit, at least one relay, and at least one state detection circuit according to any one of claims 1 to 5; wherein: Each of the relays serves as the relay to be tested of the state detection circuit corresponding to itself; The output end of each of the drive control circuits is connected to the coil in the relay corresponding to itself; Between the positive pole of the DC side of the power conversion device and the positive pole of the battery pack in the vehicle, at least one of the relays is connected in series; And / or, Between the negative pole of the DC side of the power conversion device and the negative pole of the battery pack in the vehicle, at least one of the relays is connected in series.

7. The charging pile according to claim 6, wherein, Further including: At least one drive state detection circuit; wherein: Each of the drive control circuits serves as the detection object of the drive state detection circuit corresponding to itself.

8. The charging pile according to claim 7, wherein The drive state detection circuit includes: a second diode branch and at least two fifth resistor branches; All the fifth resistor branches are connected in series. One end of the formed series branch is connected to the output end of the power supply, and the other end of the formed series branch is connected to either pole of the output end of the drive control circuit corresponding to the drive state detection circuit. The cathode of the second diode branch is connected to the connection point of any two of the fifth resistor branches, and the anode of the second diode branch serves as the output end of the drive state detection circuit. Or, The cathode of the second diode branch is connected to the drive circuit of the relay through at least one of the fifth resistor branches. The anode of the second diode branch is connected to the output end of the first power supply through at least one of the fifth resistor branches, and the anode of the second diode branch serves as the output end of the drive state detection circuit.

9. The charging pile according to claim 8, characterized in that, The drive state detection circuit further includes: a sixth resistor branch; wherein: One end of the sixth resistor branch is connected to the connection point of any two of the fifth resistor branches, and the other end of the sixth resistor branch serves as the output end of the drive state detection circuit.

10. The charging pile according to claim 8 or 9, characterized in that, The power conversion device includes a DC / DC conversion device or a DC / AC conversion device.

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