A vehicle end detection method and vehicle for unplugging the gun while charged

Abstract

The present invention provides a vehicle-end detection method and a vehicle for unplugging the charging gun while the vehicle is charged. By using the difference in the pin sizes between the charging pins in the charging gun specified by the national standard and the signal pins of the vehicle-end plugging gun confirmation signal (CC2 signal), the judgment of unplugging the charging gun while the vehicle is charged is made by using the time difference between the disconnection of the charging current and the change of the CC2 signal, which solves the problem that it is difficult to detect unplugging the charging gun at the vehicle end, and greatly improves the accuracy of the judgment of unplugging the charging gun while the vehicle is charged. In this solution, both the disconnection of the charging current and the change of the CC2 signal can be detected by the vehicle, and the vehicle does not need to judge whether the reason for the disconnection of the charging current is that the charging pile normally stops outputting or the charging gun is pulled out from the socket. Only by setting an appropriate interval time threshold, the vehicle-end detection of unplugging the charging gun while the vehicle is charged can be realized.

Description

Technical Field

[0001] The present invention relates to a method and a vehicle for detecting and unplugging a charging gun while the vehicle end is energized, and belongs to the technical field of vehicle charging. Background Art

[0002] At present, most electric commercial vehicles on the market use off-vehicle chargers for charging. When charging is completed, the charging pile obtains the charging completion information through the vehicle, and the charging pile controls to disconnect the charging current. At this time, the charging gun can be safely unplugged. If during the charging process before charging is completed, it is necessary to abort charging due to reasons such as the need to use the vehicle, then an operation needs to be performed on the charging pile to stop charging, and wait for the charging pile to disconnect the charging current before the charging gun can be unplugged from the vehicle charging port.

[0003] Under normal circumstances of stopping charging, the charging current of the charger drops below 5A. At this time, unplugging the charging gun will not cause ablation of the charging gun or the socket. During DC charging, the charging current can reach up to hundreds of amperes. If the charging gun is directly unplugged from the vehicle charging seat without operating the charging pile to stop charging, that is, unplugging the charging gun while the charger is still outputting current to the vehicle, an electric arc will be generated to ablate the charging gun and the vehicle charging seat.

[0004] Existing solutions to prevent unplugging the charging gun while energized through physical locking, that is, the charging gun is locked on the vehicle charging seat by an electronically controlled mechanical lock tongue, and the mechanical lock is released when the charging current drops below the safe value after charging ends, allowing the gun to be unplugged. However, due to the compatibility issues between the new and old national standards and the problems with the electronic lock function settings of charging manufacturers, in many charging piles, the charging gun can still be unplugged by applying force when it is mechanically locked during the charging process. Moreover, in case of an emergency, the charging gun should be able to be unplugged immediately, such as when the charging pile catches fire or when driving away without remembering to unplug the gun. Therefore, the mechanical lock of the charging gun cannot be configured to be completely locked.

[0005] In order to use management means to prevent illegal operations of unplugging the charging gun while energized, it is necessary to implement detection of unplugging the charging gun while energized. In the prior art, the detection technology of unplugging the charging gun while energized is only implemented on the charger. The charger can easily implement the detection of unplugging the charging gun while energized based on the charging gun plug-in confirmation signal and the magnitude of the output charging current.

[0006] Therefore, if the vehicle management party wants to obtain the illegal operation data of unplugging the charging gun of the electric vehicle while energized, it still needs to contact the operation service provider of the charging pile, which is rather troublesome.

[0007] In addition, when the charging pile conducts the detection of unplugging the charging gun while energized, there is also a problem of inaccurate detection. Because the charging gun plug-in confirmation signal relied on by the charging pile when judging the unplugging operation is determined by detecting that the CC1 signal during the charging process is greater than 4.8V according to the national standard, there are the following possibilities of false alarms:

[0008] 1) During the charging process, the charging gun button that controls the CC signal is pressed, but the charging gun is not unplugged; in this case, as Figure 1 shown, when the charging gun button is pressed, S is disconnected, one ground line of CC1 is disconnected, the voltage of the CC1 signal increases, and when the charging current is still output, it will be judged by the charging pile as unplugging the gun while being charged. However, at this time, only the charging gun button is pressed, and the charging path is not unplugged and disconnected. Therefore, the situation of unplugging the gun while being charged at this time is a false alarm.

[0009] 2) During the charging process, the CC signal is used for the plug-in detection of other devices to power on the corresponding device after plugging in the gun. This detection will interfere with the sampling of the CC1 signal by the charging pile, resulting in false detection and false alarms. Summary of the Invention

[0010] The purpose of the present invention is to provide a method and vehicle for detecting unplugging the gun while being charged at the vehicle end to solve the problem that the vehicle end cannot detect unplugging the gun while being charged.

[0011] To achieve the above purpose, the present invention provides a method and vehicle for detecting unplugging the gun while being charged at the vehicle end. The method for detecting unplugging the gun while being charged at the vehicle end includes the following steps.

[0012] 1) The vehicle detects the charging current. When the charging current drops below the set current, record the current moment as the first moment;

[0013] 2) The vehicle detects the CC2 signal. When the CC2 signal changes, record the current moment as the second moment;

[0014] 3) Judge the time interval between the second moment and the first moment. When the time interval is less than the set time, it is determined that the gun is unplugged while being charged.

[0015] The present invention utilizes the difference in the pin sizes between the charging pin in the charging gun stipulated by the national standard and the signal pin of the plug-in confirmation signal (CC2 signal) at the vehicle end, and uses the time difference between the charging current detected at the vehicle end and the disconnection of the CC2 signal to judge unplugging the gun while being charged, solving the problem that it is difficult to detect unplugging the gun while being charged at the vehicle end, and greatly improving the accuracy of judging unplugging the gun while being charged.

[0016] According to the national standard, the length of the CC2 signal pin is about 5 millimeters longer than the charging pin. Therefore, during the process of unplugging the charging gun from the vehicle charging socket, for the vehicle, the charging current is disconnected before the CC2 signal, and at the normal unplugging speed of the gun, the time interval between the moment when the charging current is disconnected and the moment when the CC2 signal changes will not be too long, and is obviously shorter than the time interval between the moment when the charging current is disconnected and the moment when the CC2 signal changes during the process of normally disconnecting the charging current through the charging pile and then unplugging the charging gun to disconnect the CC2 signal.

[0017] In this solution, both the disconnection of the charging current and the change of the CC2 signal can be detected by the vehicle. And the vehicle does not need to judge the reason for the disconnection of the charging current, whether it is the normal stop of the charging pile from outputting or the charging gun being pulled out from the socket. Only by setting an appropriate interval time threshold, the vehicle-end detection of unplugging the gun while charging can be achieved.

[0018] Further, in step 2), the feature of the CC2 signal change is that the CC2 voltage rises from 6V to 12V.

[0019] Using the change of the vehicle-end gun insertion confirmation signal specified by the national standard to judge the unplugging operation, the solution is simple and accurate. The CC2 signal is not affected by the pressing of the charging gun button and is only related to the disconnection of the CC2 signal pin from the corresponding jack caused by unplugging the gun.

[0020] Further, in step 3), the value range of the set time is from 300ms to 500ms.

[0021] According to multiple experimental tests, for a normal unplugging operation, the time difference between the sequential disconnections of pins with a distance of two centimeters is not greater than 300 milliseconds. An additional 200 milliseconds of margin is left to avoid missing the judgment of the operation of unplugging the gun while charging with a relatively slow speed.

[0022] Further, in step 1), the set current is 5A.

[0023] Unplugging the gun with a current below 5A will not cause the socket to be ablated. Therefore, 5A is used as the current threshold to avoid misidentifying a compliant operation as unplugging the gun while charging.

[0024] A vehicle of the present invention includes a controller, and the controller executes instructions to implement the following method;

[0025] 1) Detect the charging current. When the charging current drops below the set current, record the current moment as the first moment;

[0026] 2) Detect the CC2 signal. When the CC2 signal changes, record the current moment as the second moment;

[0027] 3) Judge the interval time between the second moment and the first moment. When the interval time is less than the set time, it is determined that the gun is unplugged while charging.

[0028] Further, in step 2), the feature of the CC2 signal change is that the CC2 voltage rises from 6V to 12V.

[0029] Further, in step 3), the value range of the set time is from 300ms to 500ms.

[0030] Further, in step 1), the set current is 5A.

[0031] Further, the controller is a charging controller.

[0032] Use the charging controller of the vehicle as the detection unit for detecting unplugging the charging gun while charging. The charging controller can directly detect the magnitude of the charging current, can detect the CC2 signal at the same time, and also has computing resources. Therefore, compared with setting up an additional detection unit for detecting unplugging the charging gun while charging, it can streamline the equipment and reduce costs. Description of the Drawings

[0033] Figure 1 It is the schematic diagram of the DC charging control and guidance circuit stipulated by the national standard;

[0034] Figure 2 It is the layout diagram of the vehicle plug contacts stipulated by the national standard;

[0035] Figure 3 It is the structure size diagram of the vehicle plug stipulated by the national standard;

[0036] Figure 4 It is Figure 3 The size diagram along the A-A direction;

[0037] Figure 5 It is Figure 3 The size diagram along the B-B direction;

[0038] Figure 6 It is the flowchart of the method for detecting unplugging the charging gun while charging at the vehicle end of the present invention; Detailed Embodiments

[0039] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0040] Method Embodiment:

[0041] Figure 1 It is the DC charging control and guidance circuit stipulated in the national standard, such as Figure 1As shown in the figure, the figure includes a charging pile, a charging gun, a vehicle socket, and an electric vehicle part. The charging gun is connected to the charging pile through a cable. The charging gun and the vehicle socket are matched and connected at the dotted line, so that the charging power interfaces (DC+, DC-), signal interfaces (S+, S-, CC1, CC2), and weak current interfaces (A+, A-) are correspondingly connected and conducted. The vehicle socket is arranged on the side of the electric vehicle, so that the charging power interface is connected to the vehicle battery pack, and the signal interface and the weak current interface are connected to the vehicle controller. The charging pile includes an auxiliary power supply and a charger controller. The charger controller collects the CC1 signal at detection point 1 through the sampling resistor R1 for gun insertion confirmation at the charging pile end. The detection point 1 of the CC1 signal is connected to the ground wire through the resistor R2. A normally closed switch S is arranged on the circuit where the resistor R2 is located. The switch is mechanically linked with the charging gun button for gun removal unlocking. When the charging gun button is pressed, the switch S is disconnected. Detection point 1 is also connected to the ground wire through the corresponding contacts / pins of the charging gun, vehicle socket, and resistor R4. The above-mentioned charging gun button for gun removal unlocking is different from the existing technology electronic lock for preventing live gun removal introduced in the background technology. The charging gun button is arranged on the charging gun, linked with the mechanical locking of the charging gun to the charging socket, and also linked with the switch S. After pressing, it can manually unlock the charging gun, and at the same time, the switch S is disconnected. When the charging gun is inserted into the vehicle socket, the circuit where the monitoring point 1 and R4 are located is connected through the interface contacts of the charging gun and vehicle socket, and the voltage of detection point 1 is pulled down. When the charging gun button is pressed, the switch S is disconnected, the voltage of monitoring point 1 rises, and at the same time, when the charging gun is pulled out, the circuit where the detection point and R4 are located is disconnected, and the voltage of detection point 1 rises again, so as to realize gun insertion confirmation and gun removal detection at the charging pile end.

[0042] Even if the charging pile cuts off the charging current by the increase in the CC1 voltage caused by pressing the charging gun button to prevent live gun removal, it still takes a certain amount of time for the charging current to drop to a safe level. The time from pressing the charging gun button to completing gun removal is short, and it is still easy to have live gun removal.

[0043] The vehicle controller collects the CC2 signal through the sampling resistor R5 for gun insertion confirmation at the vehicle end. The detection point 2 of the CC2 signal is connected to the ground wire through the corresponding contacts / pins of the vehicle socket, charging gun, and resistor R3. When the charging gun is inserted into the vehicle socket, the circuit where the monitoring point 2 and R3 are located is connected through the interface contacts of the vehicle socket and charging gun, and the voltage of detection point 2 is pulled down. When the charging gun is pulled out of the vehicle socket, detection point 2 is disconnected from the ground wire, and its voltage rises.

[0044] Contactor K1 and K2 are provided on the DC charging power line, contactors K3 and K4 are provided on the low-voltage auxiliary power supply loop, and charging contactors K5 and K6 are provided on the charging line in the vehicle. Among them, contactors K1 and K2 are correspondingly connected through the DC+ and DC- interfaces on the charging gun and the vehicle socket. Resistors R2 and R3 are provided on the charging gun, and resistor R4 is provided on the vehicle socket. Figure 2 , 3 Shows the layout diagram of the vehicle socket contacts (jack contacts) and the charging gun plug contacts (pins).

[0045] At the end of normal charging, the vehicle controller determines to end the charging according to the battery pack reaching the full charge state or pressing the charging stop button at the off-vehicle charging pile in the undercharged state. The charging pile judges to end the charging based on the above two conditions. When the above charging end conditions are met, the vehicle controller starts to periodically send the "Vehicle Controller Aborts Charging Message", and disconnects contactors K5 and K6 after a certain time (which can be set by itself according to national standards). At this time, the charging current will drop below 5A (as specified in the existing national standards). When the operator-set charging end condition is reached or the "Vehicle Controller Aborts Charging Message" is received, the off-vehicle charger controller periodically sends the "Charger Aborts Charging Message" and controls the charger to stop charging, and then disconnects contactors K1 and K2.

[0046] The above two situations of normal charging stop: when the vehicle battery pack is fully charged and when the charging stop button is pressed to stop charging. In the state where the vehicle battery pack is fully charged, the vehicle controller detects and obtains the full charge information, and transmits it to the charging pile through the signal line. The charging pile stops outputting the DC charging current, and then the charging gun is unplugged at the vehicle end. At this time, there are no illegal operations at both the charger and the vehicle end. When operating the charging pile and pressing the stop charging button, the charging pile stops outputting the DC charging current. At this time, unplugging the charging gun is also not illegal and will not cause damage to the charger and the vehicle end. Illegal charging stop means unplugging the charging gun when the vehicle battery pack is not fully charged and the stop charging button of the charger is not pressed. At this time, the charging pile has not stopped charging, and the charging current is still output before unplugging, but the charging gun has been unplugged, forcibly interrupting the charging current passively. This illegal operation is unplugging the gun while the charging current has not dropped below 5A (stipulated by the existing national standard), which will cause damage to the vehicle and pose a great safety hazard to the operator. This illegal operation can be detected relatively easily at the charging pile (if the full charge information sent by the vehicle is not received, and the operation to stop charging on the pile body is not received, and the charging pile suddenly stops charging due to the disconnection of the charging gun while still outputting the charging current, it can be judged as an illegal operation of unplugging the gun while charged). However, it is difficult for the vehicle end to detect and record this situation. For the vehicle end of an electric vehicle, since it is impossible to determine whether the interruption of the charging current is due to the normal stop of the charging pile's output after operating the charging pile or due to the interruption of the current caused by unplugging the gun while charged, it is difficult to detect unplugging the gun while charged from the vehicle end.

[0047] The present invention provides a method for detecting at the vehicle end for the illegal operation of unplugging the gun while charged. According to the provisions of the Electric Vehicle Charging Interface Specification Part 3: DC Charging Interface Q / GDW1234.3 - 2014, it can be known from Figure 4 that Figure 4 for Figure 3 the A - A sectional view in the charging gun contact layout diagram, the length range of the DC charging pins of the charging power interface (DC +, DC -) is 28mm to 29.5mm (section ① in the figure). It can be known from Figure 5 that Figure 5 for Figure 3In the B-B sectional view of the charging gun contact layout diagram, it is known that the pin length range of the vehicle-end charging gun confirmation signal (CC2) of the signal interface is 33 mm to 34.5 mm (section ② in the figure). In the case of unplugging the charging gun while it is energized, due to the different lengths of the pin contacts, the DC charging pins and their mating ends (DC+, DC-) and the vehicle-end charging gun confirmation signal pins and their mating ends (CC2) will be disconnected successively. Then, the time when the vehicle detects the disconnection of the DC charging current and the change of the CC2 signal will also be different. According to the characteristics that the charging current and the change time of the CC2 signal are different due to the different lengths of the DC charging pins (DC+, DC-) and the vehicle-end charging gun confirmation signal pins (CC2) in the case of unplugging the charging gun while it is energized, the present invention proposes the following method for the vehicle-end to detect unplugging the charging gun while it is energized, such as Figure 6 is the flowchart of the method for the vehicle-end to detect unplugging the charging gun while it is energized:

[0048] 1) The vehicle detects through the charging control system or the battery management system that the charging current drops from above 5 A to below 5 A, and records this moment as t1; at this time, it may be that the charging pile stops charging normally and stops outputting the charging current, or the charging gun is unplugged illegally while it is energized, causing the charging pin to just disconnect from the mating end, and finally the charging current suddenly interrupts due to the sudden disconnection of the charging gun.

[0049] 2) The charging control system or the battery management system detects that the CC2 voltage changes from 6 V to 12 V, and records this moment as t2; at this time, the vehicle-end detects the increase of the CC2 voltage, judges that the charging gun is unplugged, and the vehicle-end charging gun confirmation signal pin just disconnects from the mating end, resulting in the change of the CC2 signal.

[0050] 3) Judge that t2 - t1 is less than the set time (for example, 500 ms), that is, determine that there is an act of unplugging the charging gun while it is energized, record it, and perform alarm and upload to the background; because the time difference between the two moments is extremely small, obviously, after the operator normally operates the charging pile to stop charging (t1), and then presses the charging gun button, the time difference between unplugging the charging gun (t2) cannot be as short as the millisecond level. This situation can only be that in the case of unplugging the charging gun while it is energized, the charger is still outputting the charging current. During the unplugging process, the shorter charging pins (DC+, DC-) disconnect from the mating end first, causing the vehicle-end to detect the interruption of the charging current. Continuing to unplug the gun, the longer vehicle-end charging gun confirmation signal pin (CC2) disconnects from the mating end in a very short time, resulting in the vehicle-end detecting the change of the CC2 voltage.

[0051] Those skilled in the art should understand that the setting of the above set time should take into account the time required for a person to operate the charging pile to stop charging at the fastest speed, wait for the charging current to drop below 5 A, then press the charging gun button, and unplug the charging gun. The set time only needs to be lower than this time to basically meet the detection requirements for unplugging the charging gun while it is energized.

[0052] When performing the illegal operation of pulling out the gun with power on, a charging current of, for example, 250A is charged into the electric vehicle battery pack through the charging gun and the vehicle socket. Because the charging power interface pins (DC+, DC-) and the vehicle-end gun confirmation signal pins (CC2) are integrated on the same charging gun plug and the CC2 signal pins are longer than the charging pins (DC+, DC-), during the process of pulling out the charging gun, the charging pins (DC+, DC-) and the contacts corresponding to the vehicle socket are disconnected first. After the disconnection, the charging current will drop to below 5A, followed by the longer vehicle-end gun confirmation signal pin (CC2) being disconnected. After the disconnection, the CC2 signal will be increased from 6V to 12V according to the national standard due to the disconnection of the grounding through the resistor R3. There is a length difference of 3.5mm to 6.5mm between the two pins. This length difference determines the time difference between the reduction of the charging current and the increase of the CC2 signal voltage when the gun is pulled out with power on. According to the general gun pulling action speed, when it is detected that this time difference is less than 300 to 500 milliseconds, it is obviously an illegal operation of pulling out the gun with power on.

[0053] During normal operation when the battery is not fully charged, the operator first cancels charging through the charging pile control panel. After a series of communication processing, the charging pile turns off the rectifier, DC / DC and other devices, and disconnects the charging contactors K1 and K2. At this time, the charging current is reduced to a safe range of less than 5A for pulling out the gun. According to the operating specifications, the operator confirms through the charging pile that the charging current has dropped to a safe range, and then holds the charging gun to pull out the gun. After pulling out the gun, the CC2 signal changes due to the disconnection of the CC2 signal. In this process, the time interval between the charging current being reduced to the change of the CC2 signal is obviously greater than 300 to 500 milliseconds.

[0054] Vehicle Example:

[0055] The vehicle of this embodiment adopts a method for detecting the live gun pulling out at the vehicle end. The method for detecting the live gun pulling out at the vehicle end has been clearly introduced in the method embodiment and will not be repeated here.

[0056] The present invention provides a method and a vehicle for detecting the live gun pulling out at the vehicle end. By comparing the charging stop time t1 and the gun pulling out time t2, it is determined whether the gun is pulled out while the power is on. The behavior of the charging operator pulling out the gun while the power is on can be obtained in time at the vehicle end and an alarm can be given in the background. Compared with the data of the live gun pulling out operation obtained at an off-vehicle charging pile, the data is more accurate.

Claims

1. A vehicle-end detection method for unplugging a gun while energized, characterized in that, including the following steps, 1) The vehicle detects the charging current. When the charging current drops below the set current, record the current moment as the first moment; 2) The vehicle detects the CC2 signal. When the CC2 signal changes, record the current moment as the second moment; 3) Judge the interval time between the second moment and the first moment. When the interval time is less than the set time, it is determined that the gun is unplugged while charged; the set time is in milliseconds.

2. The vehicle-end detection method for charging gun unplugging according to claim 1, wherein, In step 2), the feature of the CC2 signal change is that the CC2 voltage rises from 6V to 12V.

3. The vehicle-end detection method for unplugging the charging gun while charged according to claim 2, wherein, In step 3), the value range of the set time is from 300ms to 500ms.

4. The vehicle-end detection method for unplugging the gun while energized according to claim 3, wherein, In step 1), the set current is 5A.

5. A vehicle, characterized in that, including a controller, and the controller executes instructions to implement the following method; 1) Detect the charging current. When the charging current drops below the set current, record the current moment as the first moment; 2) Detect the CC2 signal. When the CC2 signal changes, record the current moment as the second moment; 3) Judge the interval time between the second moment and the first moment. When the interval time is less than the set time, it is determined that the gun is unplugged while charged; the set time is in milliseconds.

6. The vehicle according to claim 5, wherein, In step 2), the feature of the CC2 signal change is that the CC2 voltage rises from 6V to 12V.

7. The vehicle according to claim 6, characterized in that, In step 3), the value range of the set time is from 300ms to 500ms.

8. The vehicle according to claim 7, characterized in that, In step 1), the set current is 5A.

9. The vehicle according to claim 8, characterized in that, The controller is a charging controller.

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