CN104198856A - Off-board charger test method and device - Google Patents

Abstract

An embodiment of the invention discloses an off-board charger test method and device and relates to the field of charging technologies. The off-board charger test method comprises receiving the DC (Direct Current) output side current which is output from an off-board charger, wherein the DC output side current is the low voltage DC current; controlling the DC output side current to pass through a full-bridge DC/DC converter to form the high voltage DC current which is used for inversion; controlling the high voltage DC current to pass through a pulse width modulation rectifier which works in an inverter state to generate the AC (Alternating Current) voltage; enabling the AC voltage to feed back the power energy to a power grid which is connected with a feedback network interface through the feedback network interface. According to the off-board charger test method and device, the problem that a large number of power energy losses can be produced during detection of the current off-board charger can be solved.

Description

Detection method and device for non-vehicle charger

technical field

The invention relates to the technical field of charging, in particular to a detection method and device for an off-vehicle charger.

Background technique

At present, as electric vehicles have the advantages of energy saving and environmental protection, my country has taken the development of electric vehicles as an effective means to solve urban air pollution and energy problems. At present, there are two ways to supplement the electric energy of electric vehicles: charging the whole vehicle and replacing the battery. It is an electric vehicle that uses a special replacement device in the battery replacement station to replace the exhausted replaceable battery pack and replace it with another fully charged battery pack, and then transport the exhausted battery pack to the battery charging rack. The charger performs case-by-case charging.

At present, in order to support the development of electric vehicles, power grid companies have built large-scale charging stations and battery replacement stations, equipped with a large number of vehicle chargers and off-board chargers. The DC voltage required for charging the power battery or replaceable battery pack, thereby charging the vehicle power battery or replaceable battery pack.

The safe and stable operation of current charging facilities is a matter of great concern to power supply companies at present. In the detection of non-vehicle chargers, it is generally necessary to apply resistive loads or electronic loads, because resistive loads or electronic loads will generate a lot of heat during operation. , so that the off-board charger will cause a large amount of power loss when it is detected.

Contents of the invention

Embodiments of the present invention provide a detection method and device for off-board chargers, so as to solve the problem that a large amount of electric energy is lost during the detection of current off-board chargers.

To achieve the above object, the present invention adopts the following technical solutions:

A detection method for an off-board charger, comprising:

Receive the DC output side current output by the off-board charger, the DC output side current is a low-voltage DC current;

controlling the current on the DC output side to pass through the full-bridge DC/DC converter to form a high-voltage DC current for inversion;

controlling the high-voltage direct current to pass through a pulse width modulation rectifier operating in an inverter state to generate an alternating voltage;

The AC voltage is used to feed back electric energy to a grid connected to the feeder interface through the feeder interface.

Further, the detection method of the off-board charger also includes:

sending a charging detection command to the off-board charger;

Acquiring the AC input side current and the AC input side voltage of the off-board charger;

Determine the first power, the first electric energy and the first harmonic value according to the working time of the off-board charger and the AC input side current and AC input side voltage;

Acquiring the DC output side current and the DC output side voltage of the off-board charger;

Determine the second power, the second electric energy and the second harmonic value according to the working time of the off-board charger and the DC output side current and DC output side voltage;

According to the first power, the first electric energy, the first harmonic value and the second power, the second electric energy, and the second harmonic value, determine the charging efficiency, voltage regulation accuracy and current regulation accuracy of the off-board charger;

Whether the off-board charger is normal is determined according to the charging efficiency, voltage stabilization accuracy, and current stabilization accuracy of the off-board charger.

Specifically, the sending a charging detection command to the off-board charger includes:

Send the off-board charger the working rated voltage, the maximum current, and the simulated remaining capacity of the battery to the off-board charger.

Further, the detection method of the off-board charger also includes:

When the remaining capacity of the simulated battery is less than a preset capacity, judging whether the current at the DC output side is constant;

If the current at the DC output side is constant, it is determined that the off-board charger is normal.

Further, the detection method of the off-board charger also includes:

When the remaining capacity of the simulated battery is greater than a preset capacity, judging whether the current at the DC output side gradually decreases, and whether the voltage at the DC output side is equal to a preset rated voltage;

If the current at the DC output side gradually decreases and the voltage at the DC output side is equal to the preset rated voltage, it is determined that the off-board charger is normal.

A detection device for an off-board charger, comprising:

The low-voltage direct current receiving unit is used to receive the direct-current output side current output by the off-board charger, and the direct-current output-side current is a low-voltage direct current;

A high-voltage DC current forming unit, configured to control the DC output side current received by the low-voltage DC current receiving unit to pass through the full-bridge DC/DC converter to form a high-voltage DC current for inversion;

An AC voltage generating unit, configured to control the high-voltage DC current formed by the high-voltage DC current forming unit to generate an AC voltage through a pulse width modulation rectifier working in an inverter state;

The power feedback unit is configured to feed back electric energy from the AC voltage generated by the AC voltage generating unit to a power grid connected to the feed network interface through the feed network interface.

Further, the detection device of the off-board charger also includes:

A charging detection instruction sending unit, configured to send a charging detection instruction to the off-board charger;

a first acquisition unit, configured to acquire the AC input side current and the AC input side voltage of the off-board charger;

The first determination unit is configured to determine the first power, the first electric energy and the first harmonic value according to the working time of the off-board charger and the AC input side current and AC input side voltage;

The second obtaining unit is used to obtain the DC output side current and the DC output side voltage of the off-board charger;

The second determining unit is used to determine the second power, the second electric energy and the second harmonic value according to the working time of the off-board charger and the current on the DC output side and the voltage on the DC output side;

A third determining unit, configured to determine the charging efficiency and voltage stabilization of the off-board charger according to the first power, first electric energy, first harmonic value and the second power, second electric energy, and second harmonic value Accuracy and steady flow accuracy;

The fourth determining unit is configured to determine whether the off-board charger is normal according to the charging efficiency, voltage regulation accuracy and current regulation accuracy of the off-board charger.

Specifically, the charging detection instruction sending unit is used for:

Send the off-board charger the working rated voltage, the maximum current, and the simulated remaining capacity of the battery to the off-board charger.

Further, the detection device of the off-board charger further includes a first judging unit;

When the remaining capacity of the simulated battery is less than a preset capacity, the first judging unit is used to judge whether the current at the DC output side is constant;

If the first determining unit determines that the current at the DC output side is constant, the fourth determining unit determines that the off-board charger is normal.

Further, the detection device of the off-board charger further includes a second judging unit;

When the remaining capacity of the simulated battery is greater than a preset capacity, the second judging unit is used to judge whether the current at the DC output side gradually decreases, and whether the voltage at the DC output side is equal to a preset value rated voltage;

If the second judging unit judges that the current on the DC output side decreases gradually, and the voltage on the DC output side is equal to the preset rated voltage, the fourth determining unit determines that the off-board charger is normal .

A detection device for an off-board charger, comprising a feeder power electronic load circuit, the feeder power electronic load circuit includes an off-board charger interface for connecting an off-board charger, a full-bridge DC/DC converter, Pulse width modulation rectifier and feeder interface for connection to the grid;

The off-vehicle charger interface, the full-bridge DC/DC converter, the pulse width modulation rectifier and the feeding network interface are connected in series;

The detection device of the off-board charger also includes an AC input side voltage sensor, an AC input side current sensor, a DC output side voltage sensor, and a DC output side current sensor;

One end of the AC input side voltage sensor and the AC input side current sensor is connected to the AC input side of the off-board charger; the other end of the AC input side voltage sensor and the AC input side current sensor is connected to a processor connection;

One end of the DC output side voltage sensor and the DC output side current sensor is connected to the DC output side of the off-board charger; the other end of the DC output side voltage sensor and the DC output side current sensor is connected to the the processor connection;

The processor is connected with a display, a human-computer interaction keyboard and a battery management system.

Specifically, the off-vehicle charger interface is provided with a direct current interface and a controller local area network bus interface;

The DC side output end of the off-board charger is connected to the full-bridge DC/DC converter through the DC interface;

The communication end of the off-board charger is connected to the battery management system through the controller area network bus interface, so that the off-board charger communicates with the battery management system.

The detection method and device of the off-board charger provided by the embodiments of the present invention can control the DC output side current to pass through the full-bridge DC/DC converter after receiving the DC output side current output by the off-board charger to form a It is used to invert the high-voltage direct current, and control the high-voltage direct current to pass through the pulse width modulation rectifier working in the inverter state to generate an alternating voltage, so that the alternating voltage is connected to the feeder network interface through the feeder network interface grid feedback power. What is set in the detection device of the off-board charger in the present invention is the feed-in power electronic load circuit, rather than the resistance load or electronic load used, so that it can feed back electric energy to the grid, and avoids the application of resistance load or electronic load. A lot of heat is generated during operation, and the off-board charger will cause a lot of power loss when it is detected.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings without any creative effort.

Fig. 1 is a flow chart 1 of a detection method for an off-board charger provided by an embodiment of the present invention;

FIG. 2 is the second flow chart of the detection method of the off-board charger provided by the embodiment of the present invention;

FIG. 3 is a third flowchart of a detection method for an off-board charger provided by an embodiment of the present invention;

Fig. 4 is a flowchart four of a detection method for an off-board charger provided by an embodiment of the present invention;

Fig. 5 is a structural schematic diagram 1 of a detection device for an off-board charger provided by an embodiment of the present invention;

Fig. 6 is a schematic structural diagram II of a detection device for an off-board charger provided by an embodiment of the present invention;

Fig. 7 is a physical structural schematic diagram 1 of a detection device for an off-board charger provided by an embodiment of the present invention;

Fig. 8 is a second schematic diagram of the physical structure of the detection device of the off-board charger provided by the embodiment of the present invention;

FIG. 9 is a schematic structural diagram of an off-board charger interface in an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in Figure 1, the detection method of the off-board charger provided by the embodiment of the present invention includes:

Step 101. Receive the DC output side current from the off-board charger, where the DC output side current is a low-voltage DC current.

Step 102 , controlling the current at the DC output side to pass through the full-bridge DC/DC converter to form a high-voltage DC current for inversion.

Step 103, controlling the high-voltage direct current to pass through the pulse width modulation rectifier working in the inverter state to generate an alternating voltage.

Step 104: Feed back the AC voltage to the power grid connected to the feeder interface through the feeder interface.

The execution subject of the detection method of the off-board charger provided in the embodiment of the present invention may be a detection device of the off-board charger.

The detection method of the off-board charger provided by the embodiment of the present invention can control the DC output side current to pass through the full-bridge DC/DC converter after receiving the DC output side current output by the off-board charger to form a The high-voltage DC current is controlled, and the high-voltage DC current is controlled to pass through the pulse width modulation rectifier working in the inverter state to generate an AC voltage, so that the AC voltage is fed back to the power grid connected to the feeder interface through the feeder interface. What is set in the detection device of the off-board charger in the present invention is the feed-in power electronic load circuit, rather than the resistance load or electronic load used, so that it can feed back electric energy to the grid, and avoids the application of resistance load or electronic load. A lot of heat is generated during operation, and the off-board charger will cause a lot of power loss when it is detected.

In addition, since the power consumption of the feed-in power electronic load circuit is relatively small, and the volume of the feed-in power electronic load is small, the detection of the off-board charger will not consume too much electric energy, and the detection device of the off-board charger is small in size. Small and easy to carry.

The frequency of the above-mentioned AC voltage is generally 50 Hz.

In order to facilitate those skilled in the art to better understand this solution, a more detailed embodiment is listed below, as shown in Figure 2, the detection method of the off-board charger in this embodiment includes:

Step 201 , sending a charging detection command to the off-board charger, the charging detection command includes the working rated voltage and maximum current of the off-board charger, and the remaining capacity of the battery to be simulated. Then step 202 or step 206 is executed.

The above rated voltage is the preset working rated voltage of the off-board charger, and the maximum current is the maximum working current of the off-board charger.

Step 202: Receive the DC output side current output by the off-board charger, where the DC output side current is a low-voltage DC current.

The DC output side current is the current for charging the battery by the off-board charger.

Step 203 , controlling the current at the DC output side to pass through the full-bridge DC/DC converter to form a high-voltage DC current for inversion.

Step 204, controlling the high-voltage direct current to pass through the pulse width modulation rectifier working in an inverter state to generate an alternating voltage.

The frequency of the above-mentioned AC voltage is generally 50 Hz.

Step 205: Feed back the AC voltage to the power grid connected to the feeder interface through the feeder interface.

Step 206, acquiring the AC input side current, AC input side voltage, DC output side current and DC output side voltage of the off-board charger.

Step 207: Determine the first power, the first electric energy and the first harmonic value according to the working time of the off-board charger, the current on the AC input side, and the voltage on the AC input side; The output side voltage determines the second power, the second electric energy and the second harmonic value.

Step 208: Determine the charging efficiency, voltage regulation accuracy and current regulation accuracy of the off-board charger according to the first power, first electric energy, first harmonic value and second power, second electric energy, and second harmonic value.

Step 209 : Determine whether the off-board charger is normal according to the charging efficiency, voltage regulation accuracy, and current regulation accuracy of the off-board charger.

Specifically, thresholds for charging efficiency, voltage stabilizing accuracy, and current stabilizing accuracy can be set in advance. When the accuracy threshold is reached, the off-board charger works normally and can charge the battery.

In addition, as shown in FIG. 3, the detection method of the off-board charger in the embodiment of the present invention may further include the following steps in step 201:

Step 210, acquiring the DC output side current of the off-board charger.

Step 211 , when the simulated remaining capacity of the battery is less than a preset capacity, determine whether the current at the DC output side is constant.

Step 212, if the current at the DC output side is constant, it is determined that the off-board charger is normal.

Step 213, if the current at the DC output side is not constant, then determine that the off-board charger is abnormal.

When the remaining capacity of the simulated battery is less than a preset capacity, generally the remaining capacity of the simulated battery is low, so a constant larger current may be required for charging. The steps 210-213 detect the charging capability of the off-board charger when the simulated remaining capacity of the battery is low.

In addition, as shown in FIG. 4, the detection method of the off-board charger in the embodiment of the present invention may further include the following steps in step 201:

Step 210, acquiring the DC output side current of the off-board charger.

Step 214 , when the simulated remaining capacity of the battery is greater than a preset capacity, determine whether the current at the DC output side decreases gradually, and whether the voltage at the DC output side is equal to a preset rated voltage.

Step 215, if the current at the DC output side decreases gradually, and the voltage at the DC output side is equal to the preset rated voltage, then it is determined that the off-board charger is normal.

Step 216, if the current at the DC output side does not decrease gradually, or the voltage at the DC output side is not equal to the preset rated voltage, then determine that the off-board charger is abnormal.

When the remaining capacity of the simulated battery is less than the maximum preset capacity, generally the remaining capacity of the simulated battery is relatively high, so a constant and equal to a preset rated voltage and a relatively small current may be required for charging. The steps 210-216 detect the charging capability of the off-board charger when the simulated remaining capacity of the battery is relatively high.

Corresponding to the detection method of the off-board charger shown in FIG. 1 to FIG. 4 above, as shown in FIG. 5 , the detection device for the off-board charger provided by the embodiment of the present invention includes:

The low-voltage direct current receiving unit 31 can receive the direct-current output side current output by the off-board charger, and the direct-current output-side current is a low-voltage direct current.

The high-voltage DC current forming unit 32 can control the DC output side current received by the low-voltage DC current receiving unit 31 to pass through the full-bridge DC/DC converter to form a high-voltage DC current for inversion.

The AC voltage generating unit 33 can control the high-voltage direct current formed by the high-voltage direct current forming unit 32 to pass through the pulse width modulation rectifier working in an inverter state to generate an alternating voltage.

The power feedback unit 34 can feed back the AC voltage generated by the AC voltage generating unit 33 to the grid connected to the feed grid interface through the feed grid interface.

Further, as shown in Figure 6, the detection device of the off-board charger also includes:

The charging detection command sending unit 35 can send the charging detection command to the off-board charger.

The first acquiring unit 36 can acquire the AC input side current and the AC input side voltage of the off-board charger.

The first determining unit 37 can determine the first power, the first electric energy and the first harmonic value according to the working time of the off-board charger, the current of the AC input side, and the voltage of the AC input side.

The second acquiring unit 38 can acquire the DC output side current and the DC output side voltage of the off-board charger.

The second determining unit 39 can determine the second power, the second electric energy and the second harmonic value according to the working time of the off-board charger, the current of the DC output side, and the voltage of the DC output side.

The third determination unit 40 can determine the charging efficiency, voltage regulation accuracy and current regulation of the off-board charger according to the first power, the first electric energy, the first harmonic value and the second power, the second electric energy, and the second harmonic value precision.

The fourth determination unit 41 can determine whether the off-board charger is normal according to the charging efficiency, voltage regulation accuracy and current regulation accuracy of the off-board charger.

Specifically, the charging detection command sending unit 35 may send the off-board charger the working rated voltage, the maximum current, and the simulated remaining capacity of the battery to the off-board charger.

Further, the detection device of the off-board charger may also include a first judging unit 42 .

When the simulated remaining capacity of the battery is less than a preset capacity, the first judging unit 42 can judge whether the current at the DC output side is constant.

If the first determining unit 42 determines that the current at the DC output side is constant, the fourth determining unit 41 determines that the off-board charger is normal.

Further, the detection device of the off-board charger further includes a second judging unit 43 .

When the simulated remaining capacity of the battery is greater than a preset capacity, the second judging unit 43 can judge whether the current at the DC output side decreases gradually, and whether the voltage at the DC output side is equal to a preset rated voltage.

If the second judging unit 43 judges that the current at the DC output side decreases gradually and the voltage at the DC output side is equal to the preset rated voltage, the fourth determining unit 41 determines that the off-board charger is normal.

It is worth noting that, the specific implementation manner of the detection device of the off-board charger provided by the embodiment of the present invention may refer to the method embodiments in FIGS. 1 to 4 , and details are not repeated here.

The detection device of the off-board charger provided by the embodiment of the present invention can control the DC output side current to pass through the full-bridge DC/DC converter after receiving the DC output side current output by the off-board charger to form a The high-voltage DC current is controlled, and the high-voltage DC current is controlled to pass through the pulse width modulation rectifier working in the inverter state to generate an AC voltage, so that the AC voltage is fed back to the power grid connected to the feeder interface through the feeder interface. What is set in the detection device of the off-board charger in the present invention is the feed-in power electronic load circuit, rather than the resistance load or electronic load used, so that it can feed back electric energy to the grid, and avoids the application of resistance load or electronic load. A lot of heat is generated during operation, and the off-board charger will cause a lot of power loss when it is detected.

In addition, as shown in FIG. 7 , the detection device 50 for an off-board charger provided by the embodiment of the present invention includes a feeder power electronic load circuit 51, and the feeder power electronic load circuit 51 includes an off-board charger for connecting to an off-board charger. An on-board charger interface 52 , a full-bridge DC/DC converter 53 , a pulse width modulation rectifier 54 and a feeder interface 55 for connecting to the power grid.

The off-board charger interface 52 , the full-bridge DC/DC converter 53 , the pulse width modulation rectifier 54 and the feeding network interface 55 are connected in series.

Specifically, the feed network interface may be an electromagnetic compatibility (Electromagnetic Compatibility, EMC for short) board.

The detection device 50 of the off-board charger further includes an AC input side voltage sensor 56 , an AC input side current sensor 57 , a DC output side voltage sensor 58 , and a DC output side current sensor 59 .

One end of the AC input side voltage sensor 56 and the AC input side current sensor 57 is connected to the AC input side of the off-board charger; the other end of the AC input side voltage sensor 56 and the AC input side current sensor 57 is connected to a processing Device 60 is connected.

One end of the DC output side voltage sensor 58 and the DC output side current sensor 59 is connected to the DC output side of the off-board charger; the other end of the DC output side voltage sensor 58 and the DC output side current sensor 59 is connected to the processor 60 connect.

The processor 60 is connected with a display 61 , a human-computer interaction keyboard 62 and a battery management system 63 .

The battery management system 63 may include a DC characteristic comprehensive tester and an internal resistance tester, and the specific models may be, for example, BMS.EV01, BMS.EV02, or BMS.EV03.

Specifically, as shown in FIG. 8 , the off-board charger interface 52 is provided with a direct current interface 64 and a controller area network bus interface 65 .

The DC side output end of the above-mentioned off-board charger is connected to the full-bridge DC/DC converter 53 through the DC interface 64 .

The communication terminal of the above-mentioned off-board charger is connected to the battery management system 63 through the controller area network bus interface 65 , so that the off-board charger communicates with the battery management system 63 .

For the specific structure of the off-board charger interface 52, as shown in Figure 9, it includes a DC interface 64 and a controller area network bus interface 65. The DC interface 64 includes a DC interface positive pole 641 and a DC interface negative pole 642. The network bus interface 65 includes a controller area network bus interface H651 and a controller area network bus interface L652. The off-board charger interface 52 may also include a protective grounding interface 66 for connecting to the ground wire of the off-board charger. There is a controller area network bus interface resistor in the controller area network bus interface 65, and the resistance value of the resistor may be 120Ω. In addition, the off-board charger interface 52 also includes a charging connection confirmation interface 1 69 , a charging connection confirmation interface 2 70 , a low-voltage auxiliary power positive interface 71 and a low-voltage auxiliary power negative interface 72 .

In addition, as shown in FIG. 8, a temperature acquisition sensor 67 connected to the processor 60 may also be provided in the detection device 50 of the off-board charger to monitor the temperature of the feeder power electronic load circuit 51. The processor 60 The rotation speed of the fan 68 connected to the processor 60 can be adjusted according to the temperature, so as to cool down the temperature of the electronic load circuit 51 for feed-in power.

The detection device of the off-board charger provided by the embodiment of the present invention can control the DC output side current to pass through the full-bridge DC/DC converter after receiving the DC output side current output by the off-board charger to form a The high-voltage DC current is controlled, and the high-voltage DC current is controlled to pass through the pulse width modulation rectifier working in the inverter state to generate an AC voltage, so that the AC voltage is fed back to the power grid connected to the feeder interface through the feeder interface. What is set in the detection device of the off-board charger in the present invention is the feed-in power electronic load circuit, rather than the resistance load or electronic load used, so that it can feed back electric energy to the grid, and avoids the application of resistance load or electronic load. A lot of heat is generated during operation, and the off-board charger will cause a lot of power loss when it is detected.

Those skilled in the art should understand that the embodiments of the present invention may be provided as methods, systems, or computer program products. Accordingly, the present invention can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor, or processor of other programmable data processing equipment to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing equipment produce a An apparatus for realizing the functions specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to operate in a specific manner, such that the instructions stored in the computer-readable memory produce an article of manufacture comprising instruction means, the instructions The device realizes the function specified in one or more procedures of the flowchart and/or one or more blocks of the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby The instructions provide steps for implementing the functions specified in the flow chart or blocks of the flowchart and/or the block or blocks of the block diagrams.

In the present invention, specific examples have been applied to explain the principles and implementation methods of the present invention, and the descriptions of the above examples are only used to help understand the method of the present invention and its core idea; meanwhile, for those of ordinary skill in the art, according to this The idea of the invention will have changes in the specific implementation and scope of application. To sum up, the contents of this specification should not be construed as limiting the present invention.

Claims (12)

1. A detection method for an off-board charger, comprising: Receive the DC output side current output by the off-board charger, the DC output side current is a low-voltage DC current; controlling the current on the DC output side to pass through the full-bridge DC/DC converter to form a high-voltage DC current for inversion; controlling the high-voltage direct current to pass through a pulse width modulation rectifier operating in an inverter state to generate an alternating voltage; The AC voltage is used to feed back electric energy to a grid connected to the feeder interface through the feeder interface. 2. The detection method of off-board charger according to claim 1, further comprising: sending a charging detection command to the off-board charger; Acquiring the AC input side current and the AC input side voltage of the off-board charger; Determine the first power, the first electric energy and the first harmonic value according to the working time of the off-board charger and the AC input side current and AC input side voltage; Acquiring the DC output side current and the DC output side voltage of the off-board charger; Determine the second power, the second electric energy and the second harmonic value according to the working time of the off-board charger and the DC output side current and DC output side voltage; According to the first power, the first electric energy, the first harmonic value and the second power, the second electric energy, and the second harmonic value, determine the charging efficiency, voltage regulation accuracy and current regulation accuracy of the off-board charger; Whether the off-board charger is normal is determined according to the charging efficiency, voltage stabilization accuracy, and current stabilization accuracy of the off-board charger. 3. The detection method of the off-board charger according to claim 2, wherein the sending a charging detection instruction to the off-board charger comprises: Send the off-board charger the working rated voltage, the maximum current, and the simulated remaining capacity of the battery to the off-board charger. 4. The detection method of off-board charger according to claim 3, further comprising: When the remaining capacity of the simulated battery is less than a preset capacity, judging whether the current at the DC output side is constant; If the current at the DC output side is constant, it is determined that the off-board charger is normal. 5. The detection method of off-board charger according to claim 3, further comprising: When the remaining capacity of the simulated battery is greater than a preset capacity, judging whether the current at the DC output side gradually decreases, and whether the voltage at the DC output side is equal to a preset rated voltage; If the current at the DC output side gradually decreases and the voltage at the DC output side is equal to the preset rated voltage, it is determined that the off-board charger is normal. 6. A detection device for an off-board charger, characterized in that it comprises: The low-voltage direct current receiving unit is used to receive the direct-current output side current output by the off-board charger, and the direct-current output-side current is a low-voltage direct current; A high-voltage DC current forming unit, configured to control the DC output side current received by the low-voltage DC current receiving unit to pass through the full-bridge DC/DC converter to form a high-voltage DC current for inversion; An AC voltage generating unit, configured to control the high-voltage DC current formed by the high-voltage DC current forming unit to generate an AC voltage through a pulse width modulation rectifier working in an inverter state; The power feedback unit is configured to feed back electric energy from the AC voltage generated by the AC voltage generating unit to a power grid connected to the feed network interface through the feed network interface. 7. The detection device of off-board charger according to claim 6, further comprising: A charging detection instruction sending unit, configured to send a charging detection instruction to the off-board charger; a first acquisition unit, configured to acquire the AC input side current and the AC input side voltage of the off-board charger; The first determination unit is configured to determine the first power, the first electric energy and the first harmonic value according to the working time of the off-board charger and the AC input side current and AC input side voltage; The second obtaining unit is used to obtain the DC output side current and the DC output side voltage of the off-board charger; The second determining unit is used to determine the second power, the second electric energy and the second harmonic value according to the working time of the off-board charger and the current on the DC output side and the voltage on the DC output side; A third determining unit, configured to determine the charging efficiency and voltage stabilization of the off-board charger according to the first power, first electric energy, first harmonic value and the second power, second electric energy, and second harmonic value Accuracy and steady flow accuracy; The fourth determining unit is configured to determine whether the off-board charger is normal according to the charging efficiency, voltage regulation accuracy and current regulation accuracy of the off-board charger. 8. The detection device for an off-board charger according to claim 7, wherein the charging detection instruction sending unit is specifically used for: Send the off-board charger the working rated voltage, the maximum current, and the simulated remaining capacity of the battery to the off-board charger. 9. The detection device for the off-board charger according to claim 8, further comprising a first judging unit; When the remaining capacity of the simulated battery is less than a preset capacity, the first judging unit is used to judge whether the current at the DC output side is constant; If the first determining unit determines that the current at the DC output side is constant, the fourth determining unit determines that the off-board charger is normal. 10. The detection device for the off-board charger according to claim 8, further comprising a second judging unit; When the remaining capacity of the simulated battery is greater than a preset capacity, the second judging unit is used to judge whether the current at the DC output side gradually decreases, and whether the voltage at the DC output side is equal to a preset value rated voltage; If the second judging unit judges that the current on the DC output side decreases gradually, and the voltage on the DC output side is equal to the preset rated voltage, the fourth determining unit determines that the off-board charger is normal . 11. A detection device for an off-board charger, characterized in that it includes a feed-in power electronic load circuit, and the feed-in power electronic load circuit includes an off-board charger interface for connecting an off-board charger, a full-bridge DC/DC converter, pulse width modulation rectifier and feeder interface for connecting to the grid; The off-vehicle charger interface, the full-bridge DC/DC converter, the pulse width modulation rectifier and the feeding network interface are connected in series; The detection device of the off-board charger also includes an AC input side voltage sensor, an AC input side current sensor, a DC output side voltage sensor, and a DC output side current sensor; One end of the AC input side voltage sensor and the AC input side current sensor is connected to the AC input side of the off-board charger; the other end of the AC input side voltage sensor and the AC input side current sensor is connected to a processor connection; One end of the DC output side voltage sensor and the DC output side current sensor is connected to the DC output side of the off-board charger; the other end of the DC output side voltage sensor and the DC output side current sensor is connected to the the processor connection; The processor is connected with a display, a human-computer interaction keyboard and a battery management system. 12. The detection device of the off-board charger according to claim 11, wherein the off-board charger interface is provided with a direct current interface and a controller area network bus interface; The DC side output end of the off-board charger is connected to the full-bridge DC/DC converter through the DC interface; The communication end of the off-board charger is connected to the battery management system through the controller area network bus interface, so that the off-board charger communicates with the battery management system.