WO2018201764A1

WO2018201764A1 - Electric vehicle direct current charging control guiding auxiliary circuit and system and control method

Info

Publication number: WO2018201764A1
Application number: PCT/CN2018/074512
Authority: WO
Inventors: 倪峰; 张萱; 李旭玲; 刘永东; 李志刚; 董新生; 施玉祥; 孙远; 何雪枫; 叶建德; 张伟
Original assignee: 南瑞集团有限公司; 国网电力科学研究院有限公司; 国电南瑞科技股份有限公司; 国网上海市电力公司; 国家电网公司
Priority date: 2017-05-03
Filing date: 2018-01-30
Publication date: 2018-11-08
Also published as: CN107415723A; CN107415723B

Abstract

An electric vehicle direct current charging control guiding auxiliary circuit, comprising a connection interface (1) and a connection interface (2) disposed at an off-board charger, and a connection interface (3) and a connection interface (4) disposed on an electric vehicle. A monitoring point (4) and a resistor R8 are sequentially disposed between the connection interface (2) and a positive electrode of a pull-up power source U1 of the off-board charger. A resistor R7, a switch K8, and a monitoring point (3) are connected in series between the connection interface (1) and the positive electrode of the pull-up power source U1 of the off-board charger. The monitoring point (3) is not directly connected to the positive electrode of the pull-up power source U1. A monitoring point (5) and a resistor R9 are sequentially disposed between the connection interface (3) and a protective earthing conductor PE in the electric vehicle. A resistor R10, a switch K9 and a monitoring point (6) are connected in series between the connection interface (4) and the protective earthing conductor PE in the electric vehicle. The monitoring point (6) is not directly connected to the protective earthing conductor PE in the electric vehicle. During operation, the interface (3) is electrically connected to the interface (1), and the interface (4) is electrically connected to the interface (2). A system using the auxiliary circuit and a control method for the auxiliary circuit are also disclosed. The auxiliary circuit expands control, facilitates faster response, improves reliability and compatibility, and can determine the location of broken PE pins.

Description

Electric vehicle DC charging control guiding auxiliary circuit, system and control method thereof

Technical field

The invention relates to an electric vehicle DC charging control guiding auxiliary circuit and system and a control method thereof.

Background technique

The electric vehicle charging market has developed rapidly. At the end of 2015, the five national charging standards for GB/T 18487.1 "Electric Vehicle Conductive Charging System Part 1 General Requirements" were officially released. China's DC charging program is one of the four international charging programs. It has been included in the IEC 61851-23 standard. With the popularization and promotion of standardization, the following technical blind spots exist in the standard during the construction of charging facilities:

First, in the existing design, there is no hard node signal in China's DC charging scheme. When an emergency occurs during charging, only the data communication message is used as a trigger, and the response speed is slow and the reliability is low.

Second, according to the control guiding circuit in the existing standard, as shown in the lower part of Fig. 1, neither the charging device nor the vehicle can detect the broken pin of the protective grounding wire PE in the vehicle interface, resulting in the presence of the cable during use. Danger of connector pin contacts.

Third, the standard does not clearly stipulate the auxiliary power supply as the starting point of the timing. The non-vehicle charger and the electric vehicle are inconsistently processed, which is easy to cause the communication timeout misjudgment, resulting in the failure to charge; and the vehicle auxiliary power supply negative A- is grounded in the standard It is not defined; if A- is connected to PE, two PE circuits will be formed between the off-board charger and the electric vehicle, which poses serious risks in detection and safety.

Fourth, the original standard can not solve the judgment of the circuit version through the hardware signal, it is difficult to solve the problem of forward compatibility.

Summary of the invention

In view of the above problems, the present invention provides a DC charging control guidance auxiliary circuit and system and a control method for the electric vehicle, and improves the reliability and timeliness of the DC high-power charging by setting an auxiliary circuit in the off-board charger end and the electric vehicle end; Further, the fast judgment and real-time response to the fault detection are realized, and the problem that the PE broken needle cannot be detected and forward compatible is solved. The invention can provide a charging device manufacturer or an electric vehicle manufacturer with means and tools for effectively detecting and evaluating abnormal faults.

In order to achieve the above technical effects and achieve the above technical effects, the present invention is achieved by the following technical solutions:

The electric vehicle DC charging control guiding auxiliary circuit comprises a connection interface 1 and a connection interface 2 which are arranged on the off-board charger end, and a connection interface 3 and a connection interface 4 which are arranged on the electric vehicle end:

The connection interface 2 and the positive pole of the pull-up power source U1 of the off-board charger are sequentially provided with a monitoring point 4 and a resistor R8;

The connection interface 1 and the anode of the pull-up power source U1 of the off-board charger have a resistor R7, a switch K8 and a monitoring point 3 connected in series, wherein the monitoring point 3 is not directly connected to the anode of the pull-up power source U1;

The connection interface 3 and the protective grounding wire PE in the electric vehicle are sequentially provided with a monitoring point 5 and a resistor R9;

A resistor R10, a switch K9 and a monitoring point 6 are connected in series between the connection interface 4 and the protective ground line PE in the electric vehicle, wherein the monitoring point 6 is not directly connected to the protective ground line PE in the electric vehicle;

In operation, the connection interface 3 is electrically connected to the connection interface 1, and the connection interface 4 is electrically connected to the connection interface 2.

Preferably, the connection interface 1 and the positive terminal of the pull-up power supply U1 of the off-board charger have a monitoring point 3, a switch K8 and a resistor R7 in series;

Alternatively, the connection interface 1 and the positive terminal of the pull-up power supply U1 of the off-board charger have a switch K8, a monitoring point 3 and a resistor R7 in series;

Alternatively, the connection interface 1 and the positive terminal of the pull-up power supply U1 of the off-board charger have a monitoring point 3, a resistor R7 and a switch K8 in series.

Preferably, the connection interface 4 and the protective grounding wire PE in the electric vehicle are sequentially connected in series with a monitoring point 6, a switch K9 and a resistor R10;

Alternatively, the connection interface 4 and the protective ground line PE in the electric vehicle are sequentially connected in series with a switch K9, a monitoring point 6 and a resistor R10;

Alternatively, a monitoring point 6, a resistor R10 and a switch K9 are connected in series between the connection interface 4 and the protective ground line PE in the electric vehicle.

The electric vehicle DC charging control guiding system includes a charging connection confirmation line CC1, a charging connection confirmation line CC2, and a protective grounding wire PE that can communicate with the off-board charger and the electric vehicle, and one end of the charging connection confirmation line CC1 and the non-vehicle charger The positive pole of the pull-up power source U1 is connected, one end of the charging connection confirming line CC2 is connected to one end of the protective grounding wire PE of the electric vehicle end, and the other end of the protective grounding wire PE is grounded, and the DC charging control of the electric vehicle according to any one of the above items is also included. Guide the auxiliary circuit.

Preferably, the electric vehicle end is provided with a vehicle socket, the non-vehicle charger end is provided with a vehicle plug, and the protective grounding wire PE is connected to the off-board charger and the electric vehicle through the vehicle socket and the vehicle plug;

A resistor R1, a monitoring point 1, and a resistor R4 are sequentially disposed between one end of the charging connection confirmation line CC1 and the protective ground line PE in the vehicle socket;

The pull-up voltage U2, the resistor R5, the monitoring point 2 and the resistor R3 of the electric vehicle are sequentially disposed between one end of the charging connection confirmation line CC2 and the protective ground line PE in the vehicle plug;

The pull-up power supply U1 of the off-board charger and the negative pole of the pull-up voltage U2 of the electric vehicle are connected to the protective ground line PE, and the switch S and the resistor R2 are connected in parallel with the two ends of the pull-up power source U1, the resistor R1 and the monitoring point 1;

The monitoring point 1 is located at the off-board charger end and the monitoring point 2 is located at the electric vehicle end.

Preferred:

The off-board charger end is further provided with an auxiliary power source, the positive pole of the auxiliary power source is provided with a switch 1, one output end of the switch 1 is connected with the switch K8 and the other output end is respectively connected with the resistors R7, R8;

The negative pole of the auxiliary power source is provided with a switch 3, one output end of the switch 3 is connected to the detection point 4 and the other output end is grounded;

A switch 2 is disposed between the monitoring point 5 and the resistor R9. One output end of the switch 2 is connected to the resistor R9 and the other output end is connected to the vehicle controller of the electric vehicle end;

A switch 4 is disposed between the monitoring point 6 and the resistor R10. One output of the switch 4 is connected to the resistor R10 and the other output is connected to the vehicle controller of the electric vehicle end.

A control method for a DC charging control guiding system for an electric vehicle includes the following steps:

Step 1. Before charging, disconnect switch K8 and switch K9, the two sides do not start charging;

Step 2: After the charging connection device is completely connected, the switch K8 is closed, and when it is detected that the monitoring point 3 has a voltage, it is ready to be ready;

Step 3: Check whether the voltage of the monitoring point 4 is the pull-up voltage U1 value. If not, the charging handshake message is sent, the communication interaction between the off-board charger and the electric vehicle is started, and the entire charging process is activated.

A control method for a DC charging control guiding system of an electric vehicle, in step 2, after the charging connection device is completely connected, when detecting that the voltage of the monitoring point 6 is the pull-up voltage U1, the switch K9 is closed, waiting for the charging handshake message At the same time, it is detected whether there is voltage at the monitoring point 5, if there is voltage, and a charging handshake message is received, the communication interaction between the in-vehicle charger and the electric vehicle is started and charging is started.

The beneficial effects of the invention are:

First, the auxiliary circuit is provided with a monitoring point, which is controlled by a switch (K8) and a switch (K9), and both sides of the pile are used as a charging activation signal according to the voltage change of the monitoring point, and can be used as an auxiliary charging or advanced function signal.

Secondly, the present invention solves the problem that the current Chinese DC charging scheme has no hard node signal, slow response speed, low reliability, etc. Compared with the prior art using the fault data frame of the communication protocol, the real-time performance of the hardware node signal transmission is better. Both the vehicle and the charger can get the signal faster and give both parties more time to respond. Better compensate for the lack of reliable hardware node signal defects in the existing standards, fast response, and improve charging security.

Third, comparing the data frame processing method through software analysis, the hardware signal reliability is higher, and the influence of communication signal interference, bit error rate and transmission delay is also avoided.

Fourth, through the compatibility setting, the universal practicability of the product is greatly facilitated, and the expansion is strong, and the production cost is not increased.

Fifth, the control guidance auxiliary circuit can replace or be compatible with the standard medium-low voltage auxiliary circuit, and solve the problem that the existing solution PE broken needle cannot be detected, and help the system maintenance personnel to more accurately determine the specific broken needle through the hardware node mode. The location allows maintenance personnel to resolve faults faster, reducing system maintenance time and maintenance costs. Signal delays with simple hardware are short, and high and low level signal changes are more resistant to high frequency digital signals. The application of the invention can provide technical means and technical support for the safety application of the electric vehicle charger.

Sixth, by selecting the resistance values of R8 and R9, the hardware version can be hard coded to achieve forward compatibility of the system.

DRAWINGS

1 is a schematic structural view of a DC charging control guiding system for an electric vehicle in a prior design;

2 is a schematic view showing a specific embodiment of a DC charging control guiding system for an electric vehicle according to the present invention;

3 is a schematic view showing an embodiment of a plurality of electric vehicle DC charging control guiding systems of the present invention;

4 is a schematic structural view of a DC charging control guiding system for an electric vehicle according to the present invention;

5 is a flow chart of a method for controlling a DC charging control guidance system of an electric vehicle according to the present invention;

6 is a schematic view of a conventional vehicle in which a DC charging control guidance system for an electric vehicle is normally charged;

7 is a schematic view of the electric vehicle DC charging control guiding system PE broken in the prior design;

8 is a schematic view of the electric vehicle DC charging control guiding system of the present invention when it is normally charged;

9 is a schematic view of the electric vehicle DC charging control guiding system PE broken when the needle is broken;

FIG. 10 is a schematic view of the electric vehicle DC charging control guiding system PE when the needle is broken according to an embodiment of the present invention.

detailed description

The technical solutions of the present invention are further described in detail below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can understand the invention.

As shown in FIG. 2, the electric vehicle DC charging control guiding auxiliary circuit (the thick wire frame portion at the bottom of FIG. 2) includes a connection interface 1 and a connection interface 2 disposed at the end of the off-board charger, and a connection interface 3 provided at the electric vehicle end and The connection interface 4 is electrically connected to the connection interface 1 during operation. The connection interface 4 is electrically connected to the connection interface 2, and the interfaces are electrically connected by a charging connection device, for example, between the connection interface 1 and the connection interface 3, The connection interface 2 and the connection interface 4 are connected by a plug and a socket. After the connection interface 1 and the connection interface 3 are connected to form a low voltage auxiliary power supply line A+, the connection interface 2 and the connection interface 4 are connected to form a low voltage auxiliary power supply negative line A-.

The monitoring interface 2 and the resistor R8 are sequentially disposed between the connection interface 2 and the positive terminal of the pull-up power source U1 of the off-board charger. A monitoring point 5 and a resistor R9 are sequentially disposed between the connection interface 3 and the protective ground line PE in the electric vehicle.

The connection interface 1 and the anode of the pull-up power source U1 of the off-board charger have a resistor R7, a switch K8 and a monitoring point 3 connected in series, wherein the monitoring point 3 is not directly connected to the anode of the pull-up power source U1, that is, the monitoring point 3 and the positive voltage of the pull-up power supply U1 need to be set between the resistor R7 and / or the switch K8, for example, in Figure 3, the three in the left side of the series in the series:

The first mode: the connection interface 1 and the positive terminal of the pull-up power source U1 of the off-board charger have a monitoring point 3, a switch K8 and a resistor R7 in series; the second mode: the connection interface 1 and The switch K8, the monitoring point 3 and the resistor R7 are sequentially connected in series between the positive poles of the pull-up power source U1 of the vehicle charger; the third mode: between the connection interface 1 and the positive pole of the pull-up power source U1 of the off-board charger In series, there are monitoring point 3, resistor R7 and switch K8. For specific applications, you can choose one of them.

The connection interface 4 and the protective grounding wire PE of the electric vehicle are connected in series with a resistor R10, a switch K9 and a monitoring point 6, wherein the monitoring point 6 is not directly connected to the protective grounding wire PE in the electric vehicle, that is, the monitoring point 6 and the protection The resistor R10 and/or the switch K9 need to be set between the grounding wires PE. For example, in Figure 3, the serial connection of the 3 in the lower right side is as follows:

The first way: the connection interface 4 and the protective grounding wire PE in the electric vehicle are sequentially connected in series with the monitoring point 6, the switch K9 and the resistor R10; the second mode: the connection interface 4 and the protective ground in the electric vehicle The switch PE is connected in series with the switch K9, the monitoring point 6 and the resistor R10; the third mode: the connection interface 4 and the protective grounding wire PE in the electric vehicle are sequentially connected in series with the monitoring point 6, the resistor R10 and the switch K9.

For specific applications, you can choose one of them. And the three ways of the left and right sides can be freely combined. Resistor R7, switch K8 and monitoring point 3 are installed in the off-board charger, resistor R9 and monitoring point 5 are installed in the electric vehicle; resistor R8 and monitoring point 4 are installed in the off-board charger, switch K9, resistor R10 and monitoring Point 6 is installed in an electric vehicle. The switch K8 and the switch K9 are in an off state before charging.

The off-board charger continuously checks the voltage of the monitoring point 3, that is, the voltage between the low voltage auxiliary power line A+ and the protective ground line PE; continuously checks the voltage of the monitoring point 4, that is, the low voltage auxiliary power negative line A- and the protective ground line ( The voltage between PE).

The electric vehicle continuously checks the voltage of the monitoring point 5, that is, the voltage between the low voltage auxiliary power line A+ and the protective ground line PE; continuously checks the voltage of the monitoring point 6, that is, the low voltage auxiliary power negative line A- and the protective ground line (PE) Between the voltages.

According to the DC control guiding circuit in GB/T 18487.1-2015 and IEC 61851-23, the voltages and resistances in Figure 2 are corresponding to the corresponding standards. Therefore, in order to achieve better results, the resistance values of the resistors R7 and R9 can be Set to 500Ω, the resistance of resistors R8 and R10 can be set to 1000Ω.

Correspondingly, the electric vehicle DC charging control guiding system, as shown in FIG. 2, includes a charging connection confirmation line CC1, a charging connection confirmation line CC2, and a protective grounding wire PE that can connect the off-board charger and the electric vehicle, and the charging connection confirmation line One end of CC1 (the left end in the figure) is connected to the positive pole of the pull-up power supply U1 of the off-board charger, and one end of the charging connection confirmation line CC2 (the right end in the figure) is connected to one end of the protective grounding wire PE of the electric vehicle end, and the protective ground is connected. The other end of the line PE (the left end in the figure) is grounded, and further includes the electric vehicle DC charging control guiding auxiliary circuit according to any one of the above items.

Generally, referring to FIG. 2, the electric vehicle end is provided with a vehicle socket, the non-vehicle charger end is provided with a vehicle plug, and the protective grounding wire PE communicates with the in-vehicle charger and the electric vehicle through the vehicle socket and the vehicle plug, which need to be explained. Due to the actual application, the protective grounding wire PE is not a complete line, but is divided into multiple sections by the vehicle socket and the vehicle plug, including the protective grounding wire PE line in the off-board charger end, and the protective grounding wire PE in the vehicle plug. The line, the protective grounding wire PE line in the vehicle socket and the protective grounding wire PE line in the electric vehicle end are connected by a plug and a socket as a complete protective grounding wire PE. For convenience of description, the lines are collectively called The protective ground line PE, similarly, the charging connection confirmation lines CC1 and CC2 are similar.

A resistor R1, a monitoring point 1, and a resistor R4 are sequentially disposed between one end of the charging connection confirmation line CC1 and the protective ground line PE in the vehicle socket. The pull-up voltage U2, the resistor R5, the monitoring point 2, and the resistor R3 of the electric vehicle are sequentially disposed between one end of the charging connection confirmation line CC2 and the protective ground line PE in the vehicle plug. The pull-up power source U1 of the off-board charger and the cathode of the pull-up voltage U2 of the electric vehicle are connected to the protective ground line PE, and the switch S and the resistor R2 are connected in parallel with the pull-up power source U1, the resistor R1 and the monitoring point 1. The monitoring point 1 is located at the off-board charger end and the monitoring point 2 is located at the electric vehicle end.

In order to improve the compatibility of the system, as shown in FIG. 4, the off-board charger end is further provided with an auxiliary power source, the positive pole of the auxiliary power source is provided with a switch 1, and one output end of the switch 1 is connected with the switch K8 and the other The output terminals are connected to resistors R7 and R8, respectively. The negative pole of the auxiliary power source is provided with a switch 3, one output of which is connected to the monitoring point 4 and the other output is grounded. A switch 2 is disposed between the monitoring point 5 and the resistor R9. One output of the switch 2 is connected to the resistor R9 and the other output is connected to the vehicle controller of the electric vehicle end. A switch 4 is disposed between the monitoring point 6 and the resistor R10. One output of the switch 4 is connected to the resistor R10 and the other output is connected to the vehicle controller of the electric vehicle end. The existing design and the free switching of the present invention are implemented by four switches, as shown in FIG.

The control method of the DC charging control guiding system of the electric vehicle, the complete flow chart is shown in FIG. 5, and is described in detail below.

For normal charging, see the off-board charger terminal, including the following steps:

Or, referring to the electric vehicle end, in step 2, after the charging connection device is fully connected, when detecting that the voltage of the monitoring point 6 is the pull-up voltage U1, the switch K9 is closed, waiting for the charging handshake message, and detecting whether the monitoring point 5 is If there is voltage, if there is voltage, and the charging handshake message is received, the communication interaction between the off-board charger and the electric vehicle is started and charging is started.

Preferably, when it is detected that the monitoring point 3 has a voltage, it is determined whether the voltage of the monitoring point 4 is the value of the pull-up voltage U1 within the set T time, if not, then proceeds to step S11, otherwise, proceeds to step S12;

Step S11, determining whether to perform reservation charging, if yes, proceeding to step S13; otherwise, directly transmitting a charging handshake message;

Step S12, entering a sleep state, waiting for activation;

Step S13, determining whether the reservation time is reached, and if so, directly sending a charging handshake message, otherwise, opening the switch K8 and proceeding to step S14;

In step S14, it is determined whether the reservation time is reached. If yes, the switch K8 is closed and the charging handshake message is sent. Otherwise, the process returns to step S14 to continue to determine whether the reservation time is reached.

Preferably, during the charging process, the emergency shutdown determination is further included, which specifically includes the following steps:

Step S15, if it is determined that the system (ie, the off-board charger) needs to stop, then open the switch K8, stop charging, otherwise, proceeds to step S16;

In step S16, it is checked whether the voltage of the monitoring point 4 is the value of the pull-up voltage U1, and if so, the charging is stopped, otherwise, the process proceeds to step S15.

Correspondingly, when the electric vehicle end detects that the voltage of the monitoring point 6 is the pull-up voltage U1, the process proceeds to step S21;

Step S21, determining whether to perform reservation charging, if yes, proceed to step S22, otherwise, close the switch K9, proceeds to step S23;

Step S22, determining whether the reservation time is reached; if yes, closing the switch K9, proceeding to step S23; otherwise, continuing to determine whether the appointment time is reached;

Step S23, waiting for the charging handshake message, and detecting whether there is voltage at the monitoring point 5, if there is voltage, and receiving the charging handshake message, starting communication interaction between the off-board charger and the electric vehicle and charging, otherwise, Go to step S24;

Step S24: Determine whether the time for waiting for the charging handshake message exceeds the charging message timeout time. If yes, enter the sleep state and wait for activation. Otherwise, return to step S23.

In the charging process, the emergency stop judgment is also included, which specifically includes the following steps:

Step S25, if it is determined that the system needs to stop, then open the switch K9, stop charging, otherwise, proceed to step S26;

In step S26, it is checked whether the voltage of the monitoring point 5 has disappeared, and if so, the charging is stopped, otherwise, the process proceeds to step S25.

For a compatible system, that is, the system shown in FIG. 4, when the charging connection device is completely connected, first, compatibility judgment is required, for example, on the off-board charger end, when the charging connection device is completely connected, the switch is closed. K8, when it detects that there is voltage at monitoring point 3, it is ready to go. Otherwise, it enters the charging control flow of Appendix B of GB/T18487.1-2015; on the electric vehicle end, when the charging connection device is fully connected, when the monitoring point is detected When the voltage of 6 is not equal to the pull-up voltage U1, enter the charging control flow of Appendix B of GB/T18487.1-2015.

Among them, taking the system of Figure 2 as an example, the new monitoring points and switch states during the connection and charging process are shown in Table 1.

Table 1

For example, when compatibility is judged:

Before charging, the switch K8 in the off-board charger is off state, the switch K9 in the electric vehicle is off state, the monitoring point 3, the monitoring point 5, the monitoring point 6 have no voltage, and the monitoring point 4 voltage is the pull-up voltage U1 value. The two sides do not start charging; after the charging connection device is fully connected, the off-board charger closes the switch K8. If it detects that there is voltage at the monitoring point 3, it is judged that the electric vehicle is using the auxiliary circuit of the present invention, and the off-board charger is ready, otherwise the vehicle is not in use. The charger is transferred to the GB/T 18487.1-2015 national standard process; if the electric vehicle detects the voltage of the monitoring point 6 as the pull-up voltage U1 value, it is judged that the non-vehicle charger adopts the auxiliary circuit of the present invention and enters the reservation state judgment, otherwise the electric vehicle turns Enter GB/T 18487.1-2015 national standard process.

When making a reservation status judgment:

The off-board charger enters the reserved charging state; if it detects that the voltage of the monitoring point 4 is the pull-up voltage U1 value, it enters the sleep state until it is woken up, otherwise the switch K8 is turned off, and the reservation timing is started. When the appointment time arrives, the off-board charger closes the switch K8, detects whether the voltage of the monitoring point 4 is the pull-up voltage U1 value, such as the pull-up voltage U1 value, continues to detect the voltage of the monitoring point 4; otherwise, sends a charging handshake message, Start the communication interaction and activate the entire charging process. If it is awakened, it is judged whether the reservation time is reached. If it has arrived, the charging handshake message is sent, otherwise the switch K8 is turned off, and after the reservation time arrives, the switch K8 is closed and the communication message is sent.

The electric vehicle detection monitoring point 6 voltage is the pull-up voltage U1 value, enters the reserved charging state; when the appointment time arrives, the electric vehicle closes the switch K9, waits for the charging handshake message, and detects whether there is voltage at the monitoring point 5, if there is voltage, When the electric vehicle receives the charging handshake message, the communication interaction starts; otherwise, the sleep state is entered.

In the reservation process, when the off-board charger enters the sleep state, when the state change of the switch K9 is detected, taking the system of FIG. 2 as an example, when the voltage of the monitoring point 4 changes from the value of the pull-up voltage U1 to not the pull-up voltage U1. When the value is, it is awakened;

During the reservation process, when the electric vehicle enters the sleep state, when the state change of the switch K8 is detected, taking the system of FIG. 2 as an example, when the voltage of the monitoring point 5 changes from no voltage to voltage, it is awakened.

Taking FIG. 4 as an example, determining whether the off-board charger adopts the corresponding auxiliary circuit structure of the present invention can be determined by detecting the voltage of the monitoring point 6 when the switch K9 is turned off:

The non-vehicle charger adopting the GB/T 18487.1-2015 control guiding circuit: the voltage of the monitoring point 6 is 0V; the non-vehicle charger adopting the structure of the invention: the voltage of the monitoring point 6 is 12V.

Judging whether the electric vehicle adopts the corresponding auxiliary circuit structure of the present invention can be judged by detecting the voltage of the monitoring point 3 when the switch K8 is closed: the electric vehicle using the GB/T 18487.1-2015 control guiding circuit: the voltage of the monitoring point 3 It is 0V; the off-board charger using the structure of the present invention: the voltage of the monitoring point 3 is 6V.

Since the auxiliary circuit has a plurality of series combinations, the various schemes of FIG. 3 are taken as an example, and the monitoring points and switch states are as shown in Tables 2 and 3.

Table 2

table 3

As shown in FIGS. 6 and 7, the present invention can also solve the technical problem that the PE broken needle cannot be monitored during the current charging process. According to the DC control guiding circuit specified in GB/T 18487.1-2015 and IEC 61851-23, the PE is broken by the vehicle during the charging process. When the pull-up voltage U1 and the pull-up voltage U2 are each selected to be a nominal value of 12V, the resistor R1, the resistor R2, the resistor R3, the resistor R4, and the resistor R5 are each selected to have a nominal value of 1000 ohms. When PE breaks during charging, as shown in Figure 6, the voltage of the non-vehicle charger connection confirmation signal CC1 (ie, monitoring point 1) is in the range of 3.43V V (standard requirements monitoring point 1 voltage normal range is 3.2V- 4.8V), the voltage of the electric vehicle connection confirmation signal CC2 (ie, monitoring point 2) ranges from 6.86V (standard requirements monitoring point 2 voltage normal range is 5.2V-6.8V), summing up the current control guiding circuit and Cannot detect PE disconnection.

When selecting the auxiliary circuit provided by the present invention, the resistor R7 and the resistor R9 are each selected to have a nominal value of 500 ohms, and the resistor R8 and the resistor R9 are each selected to have a nominal value of 1000 ohms, as shown in FIGS. 8 and 9, when charging In the case of PE broken needle, the voltage of the non-vehicle charger connection confirmation signal CC1 (ie, monitoring point 1) will be from 4V to >6V (standard required monitoring point 1 voltage normal range is 3.2V-4.8V), electric vehicle connection The voltage of the confirmation signal CC2 (ie, the monitoring point 2) will be from 6V to >9V (the standard requires the monitoring point 2 voltage normal range is 5.2V-6.8V), thus completely solving the prior art problem.

When the auxiliary circuit provided by the present invention is selected, when the protection grounding continuity is lost at any position during the charging process and the mechanical lock switch S is abnormally opened, the fault position can be judged by the change of the monitoring point voltage. As shown in Figure 8, the pull-up voltage U1 and the pull-up voltage U2 are each selected to be nominally 12V. The resistor R1, the resistor R2, the resistor R3, the resistor R4, and the resistor R5 are each selected to have a nominal value of 1000 ohms, a resistor R7, and a resistor. R9 is selected as the nominal value of 500 ohms, and the resistors R8 and R9 are each selected to have a nominal value of 1000 ohms. The state of the monitoring points under various fault conditions and the evaluation are shown in Table 4.

Table 4

Of course, in the case of ensuring that the PE is abnormal, R7, R8, R9, and R10 allow multiple combinations of resistance values, and use this as the characterization information of the hardware version to facilitate the implementation of the subsequent upgrade scheme. As shown in Figure 10, R8 is changed from 1KΩ to 500Ω, and R9 is changed from 500Ω to 1KΩ. By selecting the resistance values of R8 and R9, hardware version hard coding can be realized to achieve forward compatibility of the system.

The beneficial effects of the invention are:

The above are only the preferred embodiments of the present invention, and are not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformations made by the description of the invention and the drawings are directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present invention.

Claims

The electric vehicle DC charging control guiding auxiliary circuit comprises a connection interface 1 and a connection interface 2 which are arranged on the off-board charger end, a connection interface 3 and a connection interface 4 which are arranged on the electric vehicle end, and is characterized in that:

The connection interface 2 and the positive pole of the pull-up power source U1 of the off-board charger are sequentially provided with a monitoring point 4 and a resistor R8;

The connection interface 1 and the anode of the pull-up power source U1 of the off-board charger have a resistor R7, a switch K8 and a monitoring point 3 connected in series, wherein the monitoring point 3 is not directly connected to the anode of the pull-up power source U1;

The connection interface 3 and the protective grounding wire PE in the electric vehicle are sequentially provided with a monitoring point 5 and a resistor R9;

A resistor R10, a switch K9 and a monitoring point 6 are connected in series between the connection interface 4 and the protective ground line PE in the electric vehicle, wherein the monitoring point 6 is not directly connected to the protective ground line PE in the electric vehicle;

In operation, the connection interface 3 is electrically connected to the connection interface 1, and the connection interface 4 is electrically connected to the connection interface 2.
The dc charging control guidance auxiliary circuit for an electric vehicle according to claim 1, wherein:

The connection interface 1 and the positive pole of the pull-up power source U1 of the off-board charger have a monitoring point 3, a switch K8 and a resistor R7 in series;

Alternatively, the connection interface 1 and the positive terminal of the pull-up power supply U1 of the off-board charger have a switch K8, a monitoring point 3 and a resistor R7 in series;

Alternatively, a monitoring point 3, a resistor R7, and a switch K8 are sequentially connected in series between the connection interface 1 and the positive terminal of the pull-up power source U1 of the off-board charger.
The dc charging control guidance auxiliary circuit for an electric vehicle according to claim 1, wherein:

The connection interface 4 and the protective grounding wire PE in the electric vehicle are sequentially connected in series with a monitoring point 6, a switch K9 and a resistor R10;

Alternatively, the connection interface 4 and the protective ground line PE in the electric vehicle are sequentially connected in series with a switch K9, a monitoring point 6 and a resistor R10;

Alternatively, a monitoring point 6, a resistor R10 and a switch K9 are connected in series between the connection interface 4 and the protective ground line PE in the electric vehicle.
The electric vehicle DC charging control guiding auxiliary circuit according to claim 1, wherein the connection interface 1 and the connection interface 3, the connection interface 2 and the connection interface 4 are connected by a plug and a socket, and the R7 is selected. The resistance values of R8, R9, and R10 are hard coded by the hardware version.
The dc charging control guiding auxiliary circuit for an electric vehicle according to claim 1, wherein the resistances of the resistors R7 and R9 are 500 Ω, and the resistances of the resistors R8 and R10 are 1000 Ω.
The electric vehicle DC charging control guiding system includes a charging connection confirmation line CC1, a charging connection confirmation line CC2, and a protective grounding wire PE that can communicate with the off-board charger and the electric vehicle, and one end of the charging connection confirmation line CC1 and the non-vehicle charger The positive terminal of the pull-up power supply U1 is connected, one end of the charging connection confirming line CC2 is connected to one end of the protective grounding wire PE of the electric vehicle end, and the other end of the protective grounding wire PE is grounded, and is characterized in that it further includes any one of claims 1-5. The electric vehicle DC charging control guides the auxiliary circuit.
The electric vehicle DC charging control guiding system according to claim 6, wherein the electric vehicle end is provided with a vehicle socket, the non-vehicle charger end is provided with a vehicle plug, and the protective grounding wire PE passes through the vehicle socket and the vehicle plug. Connecting off-board chargers and electric vehicles;

A resistor R1, a monitoring point 1, and a resistor R4 are sequentially disposed between one end of the charging connection confirmation line CC1 and the protective ground line PE in the vehicle socket;

The pull-up voltage U2, the resistor R5, the monitoring point 2 and the resistor R3 of the electric vehicle are sequentially disposed between one end of the charging connection confirmation line CC2 and the protective ground line PE in the vehicle plug;

The pull-up power supply U1 of the off-board charger and the negative pole of the pull-up voltage U2 of the electric vehicle are connected to the protective ground line PE, and the switch S and the resistor R2 are connected in parallel with the two ends of the pull-up power source U1, the resistor R1 and the monitoring point 1;

The monitoring point 1 is located at the off-board charger end and the monitoring point 2 is located at the electric vehicle end.
The electric vehicle DC charging control guiding system according to claim 7, wherein:

The off-board charger end is further provided with an auxiliary power source, the positive pole of the auxiliary power source is provided with a switch 1, one output end of the switch 1 is connected with the switch K8 and the other output end is respectively connected with the resistors R7, R8;

The negative pole of the auxiliary power source is provided with a switch 3, one output end of the switch 3 is connected to the monitoring point 4 and the other output end is grounded;

A switch 2 is disposed between the monitoring point 5 and the resistor R9. One output end of the switch 2 is connected to the resistor R9 and the other output end is connected to the vehicle controller of the electric vehicle end;

A switch 4 is disposed between the monitoring point 6 and the resistor R10. One output of the switch 4 is connected to the resistor R10 and the other output is connected to the vehicle controller of the electric vehicle end.
The method for controlling a DC charging control guidance system for an electric vehicle according to claim 6 or 7, comprising the steps of:

Step 1. Before charging, disconnect switch K8 and switch K9, the two sides do not start charging;

Step 2: After the charging connection device is completely connected, the switch K8 is closed, and when it is detected that the monitoring point 3 has a voltage, it is ready to be ready;

Step 3: Check whether the voltage of the monitoring point 4 is the pull-up voltage U1 value. If not, the charging handshake message is sent, the communication interaction between the off-board charger and the electric vehicle is started, and the entire charging process is activated.
The control method of the DC charging control guiding system for an electric vehicle according to claim 9, wherein in the step 2, after the charging connection device is completely connected, when the voltage of the monitoring point 6 is detected as the pull-up voltage U1, the method is closed. The switch K9 waits for the charging handshake message, and detects whether the monitoring point 5 has a voltage. If there is a voltage and receives the charging handshake message, the communication interaction between the off-board charger and the electric vehicle is started and charged.
The control method of the DC charging control guidance system for an electric vehicle according to claim 9, wherein when it is detected that the monitoring point 3 has a voltage, it is determined whether the voltage of the monitoring point 4 is the pull-up voltage U1 within the set T time. Value, if not, proceed to step S11, otherwise, proceed to step S12;

Step S11, determining whether to perform reservation charging, if yes, proceeding to step S13; otherwise, directly transmitting a charging handshake message;

Step S12, entering a sleep state, waiting for activation;

Step S13, determining whether the reservation time is reached, and if so, directly sending a charging handshake message, otherwise, opening the switch K8 and proceeding to step S14;

In step S14, it is determined whether the reservation time is reached. If yes, the switch K8 is closed and the charging handshake message is sent. Otherwise, the process returns to step S14 to continue to determine whether the reservation time is reached.
The control method of the DC charging control and guidance system for an electric vehicle according to claim 11, wherein during the charging process, the emergency shutdown determination is further included, which specifically includes the following steps:

Step S15, if it is determined that the off-board charger needs to stop, then open the switch K8, stop charging, otherwise, proceeds to step S16;

In step S16, it is checked whether the voltage of the monitoring point 4 is the value of the pull-up voltage U1, and if so, the charging is stopped, otherwise, the process proceeds to step S15.
The control method of the electric vehicle DC charging control guiding system according to claim 10, wherein when the voltage of the monitoring point 6 is detected as the pull-up voltage U1, the process proceeds to step S21;

Step S21, determining whether to perform reservation charging, if yes, proceed to step S22, otherwise, close the switch K9, proceeds to step S23;

Step S22, determining whether the reservation time is reached; if yes, closing the switch K9, proceeding to step S23; otherwise, continuing to determine whether the appointment time is reached;

Step S23, waiting for the charging handshake message, and detecting whether there is voltage at the monitoring point 5, if there is voltage, and receiving the charging handshake message, starting communication interaction between the off-board charger and the electric vehicle and charging, otherwise, Go to step S24;

Step S24: Determine whether the time for waiting for the charging handshake message exceeds the charging message timeout time. If yes, enter the sleep state and wait for activation. Otherwise, return to step S23.
The control method of the DC charging control and guidance system for an electric vehicle according to claim 13, characterized in that, in the charging process, the emergency shutdown determination is further included, which specifically includes the following steps:

Step S25, if it is determined that the system needs to stop, then open the switch K9, stop charging, otherwise, proceed to step S26;

In step S26, it is checked whether the voltage of the monitoring point 5 has disappeared, and if so, the charging is stopped, otherwise, the process proceeds to step S25.
The control method of the DC charging control guiding system for an electric vehicle according to claim 8, wherein when the charging connection device is completely connected, the switch K8 is closed, and when it is detected that the monitoring point 3 has a voltage, the preparation is ready, otherwise , enter the charging control process of Appendix B of GB/T18487.1-2015.
The control method of the DC charging control guiding system for an electric vehicle according to claim 8, wherein when the charging connection device is completely connected, when it is detected that the voltage of the monitoring point 6 is not equal to the pull-up voltage U1, the GB/ T18487.1-2015 Appendix B charging control process.
The control method of the DC charging control guiding system for an electric vehicle according to claim 6 or 7 or 8, wherein the pull-up voltage U1 and the pull-up voltage U2 are each selected to have a nominal value of 12V, and the resistor R1 and the resistor R2 are provided. Resistor R3, resistor R4, and resistor R5 are each selected to have a nominal value of 1000 ohms. Resistor R7 and resistor R9 are each selected to have a nominal value of 500 ohms. Resistor R8 and resistor R9 are each selected to have a nominal value of 1000 ohms.

When the voltage of the monitoring point 1 is changed from 4V to 6V, and the voltage of the monitoring point 2 is changed from 6V to 9V, it is judged that the protective grounding wire PE is broken during charging.