Short circuit detection device, control method and charging pile

Abstract

The present application relates to a short-circuit detection device and method. The device is applied to a charging pile and includes: a voltage divider module, a comparison module and a control module; the first input end of the voltage divider module is used to connect to the live wire output end of the charging pile; the second input end of the voltage divider module is used to connect to the neutral wire output end of the charging pile; the first output end of the voltage divider module is connected to the first input end of the comparison module; the second output end of the voltage divider module is connected to the second input end of the comparison module; the output end of the comparison module is connected to the input end of the control module; the first control end of the control module is connected to the first controlled end of the voltage divider module; the second control end of the control module is connected to the second controlled end of the voltage divider module; the third control end of the control module is used to connect to the main relay of the charging pile; the control module is used to control the action of the voltage divider module, and is also used to control the main relay based on the comparison result output by the comparison module when it is determined that the charging pile is short-circuited. The present application improves the safety of short-circuit detection.

Description

Technical Field

[0001] The present application relates to the field of new energy charging and battery replacement technology, and in particular to a short-circuit detection device, a control method and a charging pile. Background Art

[0002] With the development of new energy technologies, new energy charging and battery swapping technologies have emerged. In scenarios where a large number of charging loads (for example, new energy vehicles) are charged using charging piles, the issue of safe charging cannot be ignored. Currently, before a charging pile starts AC charging of the charging load, it is necessary to perform short-circuit monitoring on the output end of the charging pile to ensure that the charging pile is safe to use before starting charging.

[0003] However, the current short circuit detection method or traditional method has the problem of poor safety. Summary of the Invention

[0004] Based on this, it is necessary to provide a short-circuit detection device, a control method and a charging pile that can improve safety in response to the above technical problems.

[0005] To achieve the above objectives, in a first aspect, an embodiment of the present application provides a short circuit detection device. The device is applied to a charging pile, and the device includes: a voltage divider module, a comparison module, and a control module; wherein:

[0006] The first input end of the voltage divider module is used to connect to the live wire output end of the charging pile; the second input end of the voltage divider module is used to connect to the neutral wire output end of the charging pile;

[0007] The first output terminal of the voltage divider module is connected to the first input terminal of the comparison module for outputting a first output voltage; the second output terminal of the voltage divider module is connected to the second input terminal of the comparison module for outputting a second output voltage; the output terminal of the comparison module is connected to the input terminal of the control module; the first control terminal of the control module is connected to the first controlled terminal of the voltage divider module; the second control terminal of the control module is connected to the second controlled terminal of the voltage divider module; and the third control terminal of the control module is used to connect to the main relay of the charging pile;

[0008] The control module is used to control the action of the voltage divider module according to the on / off status of the live wire output terminal and the neutral wire output terminal; the comparison module is used to output a comparison result based on the first output voltage and the second output voltage output by the voltage divider module; the control module is also used to control the main relay to drive the live wire output terminal and the neutral wire output terminal to the off state based on the comparison result and when it is determined that the charging pile is short-circuited.

[0009] In one embodiment, the voltage dividing module includes a first voltage dividing unit, a second voltage dividing unit and a reference voltage dividing unit;

[0010] The input end of the first voltage divider unit is used to be connected to the live wire output end; the output end of the first voltage divider unit is connected to the first input end of the comparison module; the second voltage divider unit is used to be connected to the neutral wire output end of the charging pile; and the reference voltage divider unit is connected to the second input end of the comparison module.

[0011] In one embodiment, the first voltage dividing unit includes a first voltage dividing resistor, a second voltage dividing resistor, a diode, a current limiting resistor, and a first switch;

[0012] Among them, one end of the first voltage-dividing resistor is used to connect to the first power supply, the other end of the first voltage-dividing resistor is connected to one end of the second voltage-dividing resistor, and the other end of the first voltage-dividing resistor is connected to the first input end of the comparison module; one end of the second voltage-dividing resistor is connected to the negative electrode of the diode, the other end of the second voltage-dividing resistor is connected to the positive electrode of the diode, and the other end of the second voltage-dividing resistor is also used for grounding; one end of the current-limiting resistor is used to connect to the live wire output end of the charging pile, and the other end of the current-limiting resistor is connected to the positive electrode of the diode; the first switch is connected in parallel with the current-limiting resistor; the controlled end of the first switch is connected to the first control end of the control module.

[0013] In one embodiment, the second voltage-dividing unit includes a third voltage-dividing resistor; one end of the third voltage-dividing resistor is used to be connected to the neutral line output end of the charging pile, and the other end of the third voltage-dividing resistor is used to be grounded.

[0014] In one embodiment, the reference voltage divider unit includes a fourth voltage divider resistor, a fifth voltage divider resistor and a second switch; one end of the fourth voltage divider resistor is used to connect to the second power supply; the other end of the fourth voltage divider resistor is connected to the second input end of the voltage divider module, and the other end of the fourth voltage divider resistor is also used to connect to one end of the second switch; the other end of the second switch is grounded through the fifth voltage divider resistor; and the controlled end of the second switch is connected to the second control end of the control module.

[0015] In one embodiment, the first switch and / or the second switch is an analog switch.

[0016] In one embodiment, the comparison module includes a comparator and a pull-up resistor; the positive input terminal of the comparator is connected to the first output terminal of the voltage divider module; the negative input terminal of the comparator is connected to the second output terminal of the voltage divider module; the output terminal of the comparator is used to access the third power supply through the pull-up resistor; and the output terminal of the comparator is also connected to the input terminal of the control module.

[0017] In a second aspect, an embodiment of the present application provides a short circuit control method. The method is applied to the control module in the above-mentioned short circuit detection device, and the method includes:

[0018] When the live output terminal and / or the neutral output terminal are in the off state, if a positive level is received from the comparison module, the charging pile is determined to be normal, and the main relay is controlled to drive the live output terminal and the neutral output terminal to the on state;

[0019] If a negative level is received from the comparison module, the charging pile is determined to be short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to the off state;

[0020] When the live and neutral output terminals are in the on state, if the square wave signal output by the comparison module is received, the charging pile is determined to be normal, and the main relay is controlled to drive the live and neutral output terminals to remain in the on state;

[0021] If a continuous negative level is received from the comparison module output, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to the off state.

[0022] In one embodiment, the method further comprises:

[0023] When the live wire output terminal and / or the neutral wire output terminal is in an off state, disconnecting the first switch of the voltage divider module and the second switch of the voltage divider module;

[0024] If a positive level is received from the comparator output of the comparison module, the charging pile is determined to be normal, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in a conducting state;

[0025] If a negative level is received from the comparator output of the comparison module, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to the off state;

[0026] When the live wire output terminal and the neutral wire output terminal are in a conducting state, closing the first switch of the voltage divider module and the second switch of the voltage divider module;

[0027] If the square wave signal output by the comparator of the comparison module is received, the charging pile is determined to be normal, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to remain in the conductive state;

[0028] If a continuous negative level is received from the comparator output of the comparison module, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in an off state.

[0029] In a third aspect, an embodiment of the present application provides a charging pile, which includes a main relay and the above-mentioned short-circuit detection device.

[0030] One of the above technical solutions has the following advantages and beneficial effects:

[0031] The present application controls the action of the voltage divider module according to the on-off status of the live wire output terminal and the neutral wire output terminal through the control module; the comparison module outputs a comparison result based on the first output voltage and the second output voltage output by the voltage divider module; the control module also controls the main relay to drive the live wire output terminal and the neutral wire output terminal to the off state based on the comparison result and when it is determined that the charging pile is short-circuited, thereby being able to identify the short-circuit condition of the charging pile before and during charging, thereby improving charging safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 is a structural block diagram of a short-circuit detection device in one embodiment;

[0034] Figure 2 is a structural block diagram of a short-circuit detection device in another embodiment;

[0035] Figure 3 is a circuit schematic diagram of a short-circuit detection device in one embodiment;

[0036] Figure 4 A short-circuit detection circuit diagram of a short-circuit detection device in one embodiment;

[0037] Figure 5 is a short-circuit detection circuit diagram of a short-circuit detection device in another embodiment;

[0038] Figure 6 1 is a flow chart of a short circuit detection method according to an embodiment;

[0039] Figure 7 Schematic diagram of the short circuit detection process in one embodiment. DETAILED DESCRIPTION

[0040] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0042] It will be understood that the terms "first," "second," etc. used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element.

[0043] Spatially relative terms such as "under," "beneath," "beneath," "under," "above," "above," etc., may be used herein to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, spatially relative terms also include different orientations of the device in use and operation. For example, if the device in the drawings is turned over, the element or feature described as "under" or "beneath" or "beneath" the other elements will be oriented as "above" the other elements or features. Thus, the exemplary terms "under" and "under" can include both upper and lower orientations. In addition, the device can also include alternative orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptors used herein are interpreted accordingly.

[0044] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intervening element. In addition, the "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc., if there is transmission of electrical signals or data between the connected objects.

[0045] As used herein, the singular forms "a," "an," and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include," "comprising," "having," and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Furthermore, the term "and / or" as used in this specification includes any and all combinations of the relevant listed items.

[0046] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0047] In one embodiment, Figure 1 As shown, a short circuit detection device is provided. The device is applied to a charging pile and comprises: a voltage dividing module 110, a comparison module 120 and a control module 130; wherein:

[0048] The first input end of the voltage divider module 110 is used to connect to the live wire output end of the charging pile; the second input end of the voltage divider module 110 is used to connect to the neutral wire output end of the charging pile;

[0049] The first output terminal of the voltage divider module 110 is connected to the first input terminal of the comparison module 120 for outputting a first output voltage; the second output terminal of the voltage divider module 110 is connected to the second input terminal of the comparison module 120 for outputting a second output voltage; the output terminal of the comparison module 120 is connected to the input terminal of the control module 130; the first control terminal of the control module 130 is connected to the first controlled terminal of the voltage divider module 110; the second control terminal of the control module 130 is connected to the second controlled terminal of the voltage divider module 110; and the third control terminal of the control module 130 is connected to the main relay of the charging pile;

[0050] The control module 130 is used to control the operation of the voltage divider module 110 according to the on / off status of the live wire output terminal and the neutral wire output terminal; the comparison module 120 is used to output a comparison result based on the first output voltage and the second output voltage output by the voltage divider module 110; the control module 130 is also used to control the main relay to drive the live wire output terminal and the neutral wire output terminal to the off state based on the comparison result and when it is determined that the charging pile is short-circuited.

[0051] It should be noted that the main relay of the charging pile is used to control the on and off of the live wire and neutral wire of the charging pile (that is, located between the live wire input terminal L_IN and the live wire output terminal L_OUT, and between the neutral wire input terminal N_IN and the neutral wire output terminal N_OUT, such as two single-way relays or one dual-way relay).

[0052] Specifically, the voltage divider module 110 is connected to the live output terminal L_OUT of the charging pile and the neutral output terminal N_OUT of the charging pile; the control module 130 can obtain the on-off state of the live output terminal L_OUT and the neutral output terminal N_OUT according to the state of the main relay of the charging pile; furthermore, the control module 130 controls the operation of the voltage divider module 110 according to the on-off state of the live output terminal L_OUT and the neutral output terminal N_OUT; furthermore, the control module 130 can control the on-off state of the live output terminal L_OUT and the neutral output terminal N_OUT of the charging pile by controlling the main relay of the charging pile, so that when it is determined that the charging pile is short-circuited, the main relay is controlled to drive the live output terminal L_OUT and the neutral output terminal N_OUT to be in the off state;

[0053] Furthermore, when the live output terminal L_OUT and / or the neutral output terminal N_OUT of the charging pile are in the off state (i.e., before the main relay of the charging pile turns on the live output terminal L_OUT and the neutral output terminal N_OUT of the charging pile), if the control module 130 detects that the charging pile is short-circuited, the main relay is controlled to stop operating to prohibit the live output terminal L_OUT and the neutral output terminal N_OUT of the charging pile from being turned on; when the live output terminal and the neutral output terminal of the charging pile are in the on state (i.e., after the main relay of the charging pile turns on the live output terminal and the neutral output terminal N_OUT of the charging pile), if the control module 130 detects that the charging pile is short-circuited, the control module 130 controls the main relay to drive the live output terminal L_OUT and the neutral output terminal N_OUT to be in the off state;

[0054] In some examples, the live wire output terminal L_OUT can be the live wire output terminal of the main relay, and the neutral wire output terminal N_OUT can be the neutral wire output terminal of the main relay; the control module 130 can be a controller; when the live wire output terminal L_OUT and / or the neutral wire output terminal N_OUT of the charging pile are in the off state, if the controller detects that the charging pile is short-circuited, the main relay is controlled to stop operating to prohibit the live wire output terminal L_OUT and the neutral wire output terminal N_OUT of the charging pile from being turned on, and an alarm is issued; when the live wire output terminal and the neutral wire output terminal of the charging pile are in the on state, if the controller detects that the charging pile is short-circuited, the controller controls the main relay to drive the live wire output terminal L_OUT and the neutral wire output terminal N_OUT to be in the off state, and an alarm is issued.

[0055] In the embodiment of the present application, the control module controls the action of the voltage divider module according to the on-off status of the live wire output terminal and the neutral wire output terminal; the comparison module outputs a comparison result based on the first output voltage and the second output voltage output by the voltage divider module; the control module also controls the main relay to drive the live wire output terminal and the neutral wire output terminal to the off state based on the comparison result and when it is determined that the charging pile is short-circuited, thereby being able to identify the short-circuit condition of the charging pile before and during charging, thereby improving charging safety.

[0056] In one embodiment, Figure 2 As shown, the voltage dividing module 110 includes a first voltage dividing unit 112, a second voltage dividing unit 114 and a reference voltage dividing unit 116;

[0057] The input end of the first voltage divider unit 112 is used to be connected to the live wire output end; the output end of the first voltage divider unit 112 is connected to the first input end of the comparison module 120; the second voltage divider unit 114 is used to be connected to the neutral wire output end of the charging pile; the reference voltage divider unit 116 is connected to the second input end of the comparison module 120.

[0058] Specifically, the comparison module 120 can compare the input voltage of the first input terminal of the comparison module 120 input by the first voltage divider unit 112 with the input voltage of the second input terminal of the comparison module 120 input by the reference voltage divider unit 116, and output a comparison result. In some examples, the comparison result includes that the input voltage of the first input terminal is greater than the input voltage of the second input terminal, the input voltage of the first input terminal is equal to the input voltage of the second input terminal, and the input voltage of the first input terminal is less than the input voltage of the second input terminal.

[0059] In one embodiment, Figure 3 As shown, the first voltage dividing unit 112 includes a first voltage dividing resistor, a second voltage dividing resistor, a diode, a current limiting resistor and a first switch;

[0060] Among them, one end of the first voltage-dividing resistor is used to connect to the first power supply, the other end of the first voltage-dividing resistor is connected to one end of the second voltage-dividing resistor, and the other end of the first voltage-dividing resistor is connected to the first input end of the comparison module 120; one end of the second voltage-dividing resistor is connected to the negative electrode of the diode, the other end of the second voltage-dividing resistor is connected to the positive electrode of the diode, and the other end of the second voltage-dividing resistor is also used for grounding; one end of the current-limiting resistor is used to connect to the live wire output end of the charging pile, and the other end of the current-limiting resistor is connected to the positive electrode of the diode; the first switch is connected in parallel with the current-limiting resistor; the controlled end of the first switch is connected to the first control end of the control module 130.

[0061] Specifically, the first voltage divider unit 112 includes a first voltage divider resistor RL1, a second voltage divider resistor RL2, a diode DL, a current limiting resistor Rx, and a first switch SW1. One end of the first voltage divider resistor RL1 is connected to the first power supply V1, and the first switch SW1 is controlled by the control module 130. Furthermore, the control module 130 can short-circuit the current limiting resistor Rx by controlling the first switch SW1. The diode DL can raise the reference potential after voltage division to prevent negative voltage from being input to the comparison module 120. In some examples, the diode DL can be a clamping diode.

[0062] In one embodiment, the second voltage-dividing unit 114 includes a third voltage-dividing resistor; one end of the third voltage-dividing resistor is used to be connected to the neutral line output end of the charging pile, and the other end of the third voltage-dividing resistor is used to be grounded.

[0063] Specifically, the second voltage-dividing unit 114 includes a third voltage-dividing resistor RN; the neutral line output terminal N_OUT of the charging pile is grounded through the third voltage-dividing resistor RN.

[0064] In one embodiment, the reference voltage divider unit 116 includes a fourth voltage divider resistor, a fifth voltage divider resistor and a second switch; one end of the fourth voltage divider resistor is used to connect to the second power supply; the other end of the fourth voltage divider resistor is connected to the second input end of the voltage divider module 110, and the other end of the fourth voltage divider resistor is also used to connect to one end of the second switch; the other end of the second switch is grounded through the fifth voltage divider resistor; and the controlled end of the second switch is connected to the second control end of the control module 130.

[0065] Specifically, the reference voltage divider unit 116 includes a fourth voltage divider resistor Ri, a fifth voltage divider resistor Ry and a second switch SW2, wherein one end of the fourth voltage divider resistor Ri is used to connect to the second power supply V2, and the second switch SW2 is controlled by the control module 130; furthermore, the control module 130 can disconnect the loop where the fifth voltage divider resistor Ry is located by controlling the second switch SW2.

[0066] In one embodiment, the first switch and / or the second switch is an analog switch.

[0067] Specifically, the first switch SW1 and / or the second switch SW2 are analog switches (e.g., switching transistors). Analog switches have the characteristics of low power consumption, high speed, no mechanical contacts, small size, and long service life. In some examples, the ground point GND of the first switch SW1 and / or the second switch SW2 is connected to the ground to eliminate the influence of AC.

[0068] In one embodiment, the comparison module 120 includes a comparator and a pull-up resistor; the positive input terminal of the comparator is connected to the first output terminal of the voltage divider module 110; the negative input terminal of the comparator is connected to the second output terminal of the voltage divider module 110; the output terminal of the comparator is used to access the third power supply through the pull-up resistor; and the output terminal of the comparator is also connected to the input terminal of the control module 130.

[0069] Specifically, the comparison module 120 includes a comparator and a pull-up resistor Ro; the positive input terminal 3 of the comparator is connected to the first voltage divider unit 112; the negative input terminal 4 of the comparator is connected to the reference voltage divider unit 116; since most amplifier outputs are collector open-drain outputs, the output terminal 1 of the comparator is used to access the third power supply through the pull-up resistor Ro; the output terminal of the comparator is also connected to the input terminal of the control module 130 to output a DO signal to the control module 130.

[0070] In some examples, the comparator is also used to access a positive 12V power supply voltage; the output terminal 1 of the comparator is used to access a positive 12V power supply through a pull-up resistor Ro.

[0071] In some examples, after the main relay is powered on, when the live output terminal and / or the neutral output terminal are in the off state, the short circuit detection circuit is as follows: Figure 4As shown, the control module 130 controls the first switch SW1 to short-circuit the current-limiting resistor Rx, and the current-limiting resistor Rx is not connected to the circuit; the fifth voltage-dividing resistor Ry is connected to the circuit; in order to ensure that the comparator output is different from the normal situation when the short circuit occurs, the resistance value of each resistor satisfies the following formula:

[0072] V1×RL2 / (RL1+RL2)>V2×Ry / (Ri+Ry)

[0073] V1×(RL2 / / RN) / (RL1+RL2 / / RN) <V2×Ry / (Ri+Ry)

[0074] Wherein, V1 is the first power supply connected to one end of the first voltage-dividing resistor RL1; V2 is the second power supply connected to one end of the fourth voltage-dividing resistor Ri;

[0075] In some examples, after the main relay is powered on, when the live output terminal and the neutral output terminal are in the on state, the short circuit detection circuit is as follows: Figure 5 As shown, the current limiting resistor Rx is connected to the circuit; the control module 130 disconnects the loop where the fifth voltage-dividing resistor Ry is located by controlling the second switch SW2, and the fifth voltage-dividing resistor Ry is not connected to the circuit; similarly, in order to ensure that the comparator output is different from the normal situation when the short circuit occurs, the resistance value of each voltage-dividing resistor satisfies the following formula:

[0076] L_OUTmax×RL2 / (Rx+RL2)+V1×RL2 / (RL1+RL2)>V2

[0077] V1×(RL2 / / (Rx+RN)) / (RL1+RL2 / / (Rx+RN)) <V2

[0078] Wherein, L_OUTmax is the maximum value of the input voltage of the live wire output terminal L_OUT, that is, the AC input voltage divider module 110, and a larger value is selected for the resistance value to reduce power consumption;

[0079] In one embodiment, Figure 6 As shown, a short circuit control method is provided. The method is applied to the control module 130 in the above-mentioned short circuit detection device, and the method includes:

[0080] Step 610: When the live output terminal and / or the neutral output terminal are in the off state, if a positive level is received from the comparison module 120, the charging pile is determined to be normal, and the main relay is controlled to drive the live output terminal and the neutral output terminal to the on state;

[0081] Step 620: If a negative level is received from the comparison module 120, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in the off state;

[0082] Step 630: When the live and neutral output terminals are in the on state, if the square wave signal output by the comparison module 120 is received, the charging pile is determined to be normal, and the main relay is controlled to drive the live and neutral output terminals to remain in the on state;

[0083] In step 640 , if a continuous negative level is received from the comparison module 120 , it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live output terminal and the neutral output terminal to be in an off state.

[0084] Specifically, after the main relay is powered on, when the live output terminal and / or the neutral output terminal are in the off state (for example, the live output terminal L_OUT and the neutral output terminal N_OUT are both not powered), the control module 130 controls the first switch SW1 and / or the second switch SW2 to operate, so that the short circuit detection circuit is as follows: Figure 4 As shown, the negative input voltage U- obtained by dividing the fourth voltage-dividing resistor Ri and the fifth voltage-dividing resistor Ry is input to the negative input terminal of the comparator. Under normal circumstances, the negative input voltage U- is less than the positive input voltage U+ input to the positive input terminal of the comparator, and the comparator outputs a positive level; if the charging pile is short-circuited, the positive input voltage U+ is obtained by connecting the second voltage-dividing resistor RL2 and the third voltage-dividing resistor RN in parallel and then dividing it with the first voltage-dividing resistor RL1. Since the resistance value becomes smaller after parallel connection, the voltage division becomes smaller, so that the negative input voltage U- is greater than the positive input voltage U+, and the comparator outputs a negative level; after receiving the negative DO signal, the control module 130 does not allow the main relay to turn on the live output terminal L_OUT and the neutral output terminal N_OUT, and issues an alarm;

[0085] Furthermore, after the main relay is powered on, when the live wire output terminal and the neutral wire output terminal are in the on state, the control module 130 controls the first switch SW1 and / or the second switch SW2 to operate, so that the short circuit detection circuit is as follows: Figure 5 As shown, the live output terminal L_OUT and the neutral output terminal N_OUT are connected to single-phase AC power. Under normal circumstances, the negative input voltage U- of the negative input terminal of the input comparator is the second power supply V2, and the positive input voltage U+ of the positive input terminal of the input comparator is obtained by dividing the live output terminal L_OUT and the first power supply V1 and then superimposing them. Since the live output terminal L_OUT outputs sinusoidal AC power, the positive input voltage U+ is sometimes greater than the negative input voltage U- and sometimes less than the negative input voltage U- within one cycle, and the comparator outputs a square wave signal; if the charging pile is short-circuited, the positive input voltage U+ is obtained by dividing the first power supply V1, the positive input voltage U+ is less than the negative input voltage U-, and the comparator outputs a negative level; after the control module 130 receives a continuously negative DO signal, it controls the main relay to drive the live output terminal L_OUT and the neutral output terminal N_OUT to the off state.

[0086] In some examples, such as Figure 7 As shown, after the main relay is powered on, the control module 130 detects the DO signal. If the DO signal is at a negative level, it is determined that the charging pile is short-circuited and an alarm is issued; if the DO signal is at a positive level, the control module 130 controls the main relay to close and the simulated switch action (i.e., closing the first switch SW1 and the second switch SW2). The control module 130 detects the DO signal. If the DO signal is a square wave signal, it is determined that the charging pile is normal; if the DO signal is at a negative level, it is determined that the charging pile is short-circuited, and the control module 130 controls the main relay to open and an alarm is issued.

[0087] In the embodiment of the present application, the control module can determine whether the charging pile is short-circuited based on the status of the live wire output terminal and the neutral wire output terminal, as well as the level type output by the comparison module received by the control module, and drive the live wire output terminal and the neutral wire output terminal to the off state when the charging pile is short-circuited, thereby identifying the short-circuit condition of the charging pile before and during charging, thereby improving charging safety.

[0088] In one embodiment, the method further comprises:

[0089] When the live wire output terminal and / or the neutral wire output terminal is in an off state, disconnecting the first switch of the voltage divider module 110 and the second switch of the voltage divider module 110 ;

[0090] If a positive level is received from the comparator output of the comparison module 120, the charging pile is determined to be normal, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in a conducting state;

[0091] If a negative level is received from the comparator output of the comparison module 120, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in the off state;

[0092] When the live wire output terminal and the neutral wire output terminal are in a conducting state, the first switch of the voltage dividing module 110 and the second switch of the voltage dividing module 110 are closed;

[0093] If the square wave signal output by the comparator of the comparison module 120 is received, it is determined that the charging pile is normal, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to remain in a conductive state;

[0094] If a continuous negative level is received from the comparator output of the comparison module 120 , it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in an off state.

[0095] Specifically, after the main relay is powered on, when the live output terminal and / or the neutral output terminal are in the off state (for example, both the live output terminal L_OUT and the neutral output terminal N_OUT are not powered), the control module 130 controls the first switch SW1 and the second switch SW2 to be disconnected, and the negative input voltage U- obtained by dividing the fourth voltage-dividing resistor Ri and the fifth voltage-dividing resistor Ry is input to the negative input terminal of the comparator. Under normal circumstances, the negative input voltage U- is less than the positive input voltage U+ input to the positive input terminal of the comparator, and the comparator outputs a positive level; if the charging pile is short-circuited, the positive input voltage U+ is obtained by connecting the second voltage-dividing resistor RL2 and the third voltage-dividing resistor RN in parallel and then dividing it with the first voltage-dividing resistor RL1. Since the resistance value becomes smaller after parallel connection, the voltage division becomes smaller, so that the negative input voltage U- is greater than the positive input voltage U+, and the comparator outputs a negative level; after receiving the negative DO signal, the control module 130 does not allow the main relay to turn on the live output terminal L_OUT and the neutral output terminal N_OUT, and issues an alarm;

[0096] Furthermore, after the main relay is powered on, when the live wire output terminal and the neutral wire output terminal are in the on state, the control module 130 controls the first switch SW1 and / or the second switch SW2 to be closed, and the live wire output terminal L_OUT and the neutral wire output terminal N_OUT are connected to the single-phase AC power. Under normal circumstances, the negative input voltage U- of the negative input terminal of the input comparator is the second power supply V2, and the positive input voltage U+ of the positive input terminal of the input comparator is obtained by adding the voltage of the live wire output terminal L_OUT and the first power supply V1. The output terminal L_OUT outputs sinusoidal alternating current. Within one cycle, the positive input voltage U+ is sometimes greater than the negative input voltage U- and sometimes less than the negative input voltage U-, and the comparator outputs a square wave signal. If the charging pile is short-circuited, the positive input voltage U+ is obtained by dividing the first power supply V1, the positive input voltage U+ is less than the negative input voltage U-, and the comparator outputs a negative level. After receiving a continuously negative DO signal, the control module 130 controls the main relay to drive the live wire output terminal L_OUT and the neutral wire output terminal N_OUT to the off state.

[0097] In some examples, after the main relay is powered on, the control module 130 controls the first switch SW1 and the second switch SW2 to be disconnected, and the control module 130 detects the DO signal. If the DO signal is at a negative level, it is determined that the charging pile is short-circuited and an alarm is issued; if the DO signal is at a positive level, the control module 130 controls the first switch SW1 and the second switch SW2 to be closed, and the control module 130 detects the DO signal. If the DO signal is a square wave signal, it is determined that the charging pile is normal; if the DO signal is at a negative level, it is determined that the charging pile is short-circuited, and the control module 130 controls the main relay to be disconnected and an alarm is issued.

[0098] In the embodiment of the present application, the control module controls the action of the first switch and / or the second switch of the voltage divider module according to the status of the live wire output terminal and the neutral wire output terminal, and the control module determines whether the charging pile is short-circuited based on the level type output by the received comparison module, and drives the live wire output terminal and the neutral wire output terminal to the off state when the charging pile is short-circuited, thereby realizing the identification of the short-circuit condition of the charging pile before and during charging, thereby improving charging safety.

[0099] It should be understood that although Figure 6-7 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. In addition, Figure 6-7 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0100] In one embodiment, a charging pile is provided, comprising a main relay and the above-mentioned short-circuit detection device.

[0101] Specifically, the main relay of the charging pile is used to control the switch of the live wire and neutral wire of the charging pile (the switch can be located between the live wire input terminal L_IN and the live wire output terminal L_OUT, and between the neutral wire input terminal N_IN and the neutral wire output terminal N_OUT, for example, a single-pole double-throw switch, a double-pole double-throw switch) to control the on and off states of the live wire output terminal L_OUT of the charging pile and the neutral wire output terminal N_OUT of the charging pile.

[0102] Throughout this specification, references to terms such as "some embodiments," "other embodiments," and "desired embodiments" indicate that a particular feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present application. The schematic descriptions of these terms throughout this specification do not necessarily refer to the same embodiment or example.

[0103] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0104] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A short circuit control method, characterized in that: The method is applied to a control module in a short-circuit detection device, which is applied to a charging pile. The short-circuit detection device includes: a voltage dividing module, a comparison module and a control module; wherein: The first input end of the voltage divider module is used to connect to the live wire output end of the charging pile; the second input end of the voltage divider module is used to connect to the neutral wire output end of the charging pile; The first output end of the voltage divider module is connected to the first input end of the comparison module for outputting a first output voltage; the second output end of the voltage divider module is connected to the second input end of the comparison module for outputting a second output voltage; the output end of the comparison module is connected to the input end of the control module; the first control end of the control module is connected to the first controlled end of the voltage divider module; the second control end of the control module is connected to the second controlled end of the voltage divider module; and the third control end of the control module is used to be connected to the main relay of the charging pile; The control module is configured to control the operation of the voltage divider module according to the on / off status of the live wire output terminal and the neutral wire output terminal; the comparison module is configured to output a comparison result based on the first output voltage and the second output voltage output by the voltage divider module; the control module is further configured to control the main relay to drive the live wire output terminal and the neutral wire output terminal to an off state if it is determined that the charging pile is short-circuited based on the comparison result; The method comprises: When the live wire output terminal and / or the neutral wire output terminal are in an off state, if a positive level is received from the comparison module, it is determined that the charging pile is normal, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in an on state; If a negative level is received from the comparison module, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in an off state; When the live wire output terminal and the neutral wire output terminal are in a conducting state, if the square wave signal output by the comparison module is received, it is determined that the charging pile is normal, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to remain in a conducting state; If a continuous negative level is received from the comparison module, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in an off state.

2. The short circuit control method according to claim 1, characterized in that: The voltage dividing module includes a first voltage dividing unit, a second voltage dividing unit and a reference voltage dividing unit; The input end of the first voltage divider unit is used to be connected to the live wire output end; the output end of the first voltage divider unit is connected to the first input end of the comparison module; the second voltage divider unit is used to be connected to the neutral wire output end of the charging pile; the reference voltage divider unit is connected to the second input end of the comparison module.

3. The short circuit control method according to claim 2, characterized in that: The first voltage dividing unit includes a first voltage dividing resistor, a second voltage dividing resistor, a diode, a current limiting resistor and a first switch; Among them, one end of the first voltage-dividing resistor is used to connect to the first power supply, the other end of the first voltage-dividing resistor is connected to one end of the second voltage-dividing resistor, and the other end of the first voltage-dividing resistor is connected to the first input end of the comparison module; one end of the second voltage-dividing resistor is connected to the negative electrode of the diode, the other end of the second voltage-dividing resistor is connected to the positive electrode of the diode, and the other end of the second voltage-dividing resistor is also used for grounding; one end of the current-limiting resistor is used to be connected to the live wire output end of the charging pile, and the other end of the current-limiting resistor is connected to the positive electrode of the diode; the first switch is connected in parallel with the current-limiting resistor; and the controlled end of the first switch is connected to the first control end of the control module.

4. The short circuit control method according to claim 3, characterized in that: The second voltage-dividing unit includes a third voltage-dividing resistor; one end of the third voltage-dividing resistor is used to be connected to the neutral line output end of the charging pile, and the other end of the third voltage-dividing resistor is used to be grounded.

5. The short circuit control method according to claim 4, characterized in that: The reference voltage-dividing unit includes a fourth voltage-dividing resistor, a fifth voltage-dividing resistor, and a second switch; one end of the fourth voltage-dividing resistor is used to connect to a second power supply; the other end of the fourth voltage-dividing resistor is connected to the second input end of the voltage-dividing module, and the other end of the fourth voltage-dividing resistor is also used to connect to one end of the second switch; the other end of the second switch is grounded through the fifth voltage-dividing resistor; and the controlled end of the second switch is connected to the second control end of the control module.

6. The short circuit control method according to claim 5, characterized in that: The first switch and / or the second switch is an analog switch.

7. The short circuit control method according to any one of claims 1 to 6, characterized in that: The comparison module includes a comparator and a pull-up resistor; the positive input terminal of the comparator is connected to the first output terminal of the voltage divider module; the negative input terminal of the comparator is connected to the second output terminal of the voltage divider module; the output terminal of the comparator is used to access a third power supply through the pull-up resistor; and the output terminal of the comparator is also connected to the input terminal of the control module.

8. The short circuit control method according to claim 1, characterized in that: The method further comprises: When the live wire output terminal and / or the neutral wire output terminal is in an off state, disconnecting the first switch of the voltage divider module and the second switch of the voltage divider module; If a positive level is received from the comparator output of the comparison module, it is determined that the charging pile is normal, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in a conducting state; If a negative level is received from the comparator output of the comparison module, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in an off state; When the live wire output terminal and the neutral wire output terminal are in a conducting state, closing the first switch of the voltage divider module and the second switch of the voltage divider module; If a square wave signal output by the comparator of the comparison module is received, it is determined that the charging pile is normal, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to remain in a conductive state; If a continuous negative level is received from the comparator output of the comparison module, it is determined that the charging pile is short-circuited, and the main relay is controlled to drive the live wire output terminal and the neutral wire output terminal to be in an off state.

9. A charging pile, characterized in that: The charging pile includes a main relay and a short-circuit detection device; Wherein, the control module in the short-circuit detection device is used to execute the short-circuit control method according to any one of claims 1 to 8.

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