CN210234707U - Novel alternating-current charging stake convenient to carry out quantity value traceability - Google Patents
Novel alternating-current charging stake convenient to carry out quantity value traceability Download PDFInfo
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- CN210234707U CN210234707U CN201920825107.8U CN201920825107U CN210234707U CN 210234707 U CN210234707 U CN 210234707U CN 201920825107 U CN201920825107 U CN 201920825107U CN 210234707 U CN210234707 U CN 210234707U
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- 238000001514 detection method Methods 0.000 claims description 13
- 238000006243 chemical reaction Methods 0.000 claims description 8
- 230000004907 flux Effects 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 6
- 230000000875 corresponding Effects 0.000 description 4
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Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. batteries
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02T90/10—Technologies relating to charging of electric vehicles
- Y02T90/12—Electric charging stations
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02T90/10—Technologies relating to charging of electric vehicles
- Y02T90/16—Information or communication technologies improving the operation of electric vehicles
Abstract
The utility model discloses a novel alternating-current charging stake convenient to carry out magnitude traceability, including the return circuit that charges, fill electric pile control module, 0.02 level electric energy metering module, power supply plug and human-computer interaction interface, the return circuit that charges, 0.02 level electric energy metering module, power supply plug and human-computer interaction interface all with fill electric pile control module electric connection, the input of return circuit inserts outside three-phase four-wire alternating-current power grid, the output of return circuit that charges intersects streamline L1, L2, L3 and well line N, it all inserts power supply plug, the parallelly connected 0.02 level electric energy metering module that inserts of the output of return circuit that charges simultaneously. When the device is applied, the electric energy metering accuracy grade can be improved to 0.02 grade, the measured electric parameter value can be used as a metering basis for charging a user, and can also be used as a metering standard to realize source tracing calibration of parameter values such as output voltage, current and the like in the charging process.
Description
Technical Field
The utility model relates to a fill electric pile technical field, concretely relates to novel alternating-current charging stake convenient to carry out quantity value traceability.
Background
With the continuous development of new energy industry, more and more alternating-current charging piles are put into daily operation, detection equipment serving for the alternating-current charging piles is increased, the measurement value tracing of the detection equipment at present mostly adopts a calibration mode, a three-phase power source and a three-phase standard power electric energy meter are required to be combined into a test system to complete calibration, and wiring is complex during calibration.
The current alternating-current charging pile is used as a power supply device to provide a charging power supply for an electric automobile, charging and charging are carried out according to charging energy, the electric energy metering accuracy of the alternating-current charging pile mainly depends on the accuracy of an alternating-current electric energy meter installed in the pile, the electric energy metering standard of the current alternating-current charging pile for the electric automobile only requires 2.0 levels for the accuracy grade of the electric energy meter, the metering accuracy is low, metering data can only serve as the metering basis of charging pile for charging users, and the metering data cannot serve as the metering standard to provide quantity value traceability for alternating-current charging pile detection equipment.
SUMMERY OF THE UTILITY MODEL
The utility model discloses not enough to prior art exists, provide the novel alternating-current charging stake of being convenient for carry out the quantity value and tracing to the source, when it was used, can effectively improve electric energy measurement degree of accuracy grade, the electric parameter value that it recorded both can regard as the measurement foundation to the user charge, also can regard as the calibration of tracing to the source of measurement standard realization to parameter values such as output voltage, electric current in the charging process.
The utility model discloses a following technical scheme realizes:
the novel alternating-current charging pile convenient for magnitude tracing comprises a charging loop, a charging pile control module, a 0.02-level electric energy metering module, a power supply plug and a human-computer interaction interface, wherein the charging loop, the 0.02-level electric energy metering module, the power supply plug and the human-computer interaction interface are electrically connected with the charging pile control module, the input end of the charging loop is connected with an external three-phase four-wire alternating-current power grid, the output end of the charging loop outputs three-phase intersecting flow lines L1, L2, L3 and a middle line N which are all connected with the power supply plug, meanwhile, the output end of the charging loop is connected with the 0.02-level electric energy metering module in parallel, the 0.02-level electric energy metering module comprises a front end plate, a sampling plate, a master control DSP, a 485 communication module and an electric energy pulse module, the master control DSP is respectively connected with the sampling plate, the front end plate, the current sensors are respectively connected with three-phase alternating current lines L1, L2 and L3 to collect current signals, and the voltage sensors are respectively connected with three-phase alternating current lines L1, L2, L3 and a neutral line N to collect voltage signals.
Preferably, the current sensor is a zero-flux transformer, the load impedance value of the zero-flux transformer is less than 1 ohm, and an I/V conversion circuit is arranged.
Preferably, the voltage sensor comprises an amplifying circuit and a following circuit which are connected with each other, wherein the amplifying circuit is provided with an AD8221 precision instrument amplifier, and the following circuit is provided with an OP2277 operational amplifier.
Preferably, the sampling plate is provided with an A/D converter which is an 18-bit charge redistribution successive approximation type analog-to-digital converter, model number AD 7608.
Preferably, the master control DSP is a DSP processor, and is provided with an input terminal and two output terminals, the input terminal is connected with the a/D converter to receive the converted digital signal, and the two output terminals are respectively connected with the 485 communication module and the electric energy pulse module to output the 485 signal and the electric energy pulse signal.
Preferably, the 485 communication module adopts a MAX485 chip, an input terminal of the MAX485 chip is connected with the master control DSP, and an output terminal of the MAX485 chip is connected with the charging pile control module.
Preferably, the electric energy pulse module adopts an NE555 chip to form a Schmitt trigger, and an input terminal of the Schmitt trigger is connected with the main control DSP.
Preferably, the alternating-current charging pile detection device is further arranged, an electric energy pulse input interface and a vehicle socket are arranged in the alternating-current charging pile detection device, the electric energy pulse input interface is connected with the electric energy pulse module, and the vehicle socket is connected with the power supply plug.
The utility model discloses novel alternating-current charging stake convenient to carry out quantity value and trace to source has following advantage and beneficial effect: the accuracy grade of the 0.02-grade standard three-phase standard alternating-current charging pile reaches 0.02 grade, so the displayed charging output voltage, current and electric energy values can be used as metering standards to calibrate the detection equipment of the alternating-current charging pile. In addition, when the 0.02-level standard three-phase standard alternating-current charging pile is used for calibrating the alternating-current charging pile detection equipment, the testing wiring can be completed only by connecting the detection equipment to a power grid and connecting a charging plug and an electric energy pulse signal to a corresponding interface of the calibrated alternating-current charging pile detection equipment, the wiring is simple, and the calibration work can be completed without a plurality of devices; the function expansion is realized without influencing the daily charging function of the charging equipment of the electric automobile.
Drawings
The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:
fig. 1 is a schematic structural view of the present invention;
fig. 2 is a schematic structural diagram of a 0.02-level electric energy metering module of the present invention;
FIG. 3 is an I/V conversion circuit diagram of the present invention;
fig. 4 is a circuit diagram of the voltage sensor of the present invention;
FIG. 5 is a schematic diagram of an A/D converter according to the present invention;
FIG. 6 is a schematic diagram of the main control DSP of the present invention;
fig. 7 is a schematic diagram of a 485 communication module according to the present invention;
fig. 8 shows an electric energy pulse module according to the present invention.
Reference numbers and corresponding part names in the drawings:
the method comprises the following steps of 1-charging loop, 2-charging pile control module, 3-0.02 level electric energy metering module, 4-power supply plug and 5-human-computer interaction interface.
Detailed Description
To make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the following examples and drawings, and the exemplary embodiments and descriptions thereof of the present invention are only used for explaining the present invention, and are not intended as limitations of the present invention.
Examples
As shown in fig. 1 and 2, the novel ac charging pile convenient for magnitude tracing comprises a charging loop 1, a charging pile control module 2, a 0.02-level electric energy metering module 3, a power supply plug 4 and a human-computer interaction interface 5, wherein the charging loop 1, the 0.02-level electric energy metering module 3, the power supply plug 4 and the human-computer interaction interface 5 are all electrically connected with the charging pile control module 2, the input end of the charging loop 1 is connected to an external three-phase four-wire ac power grid, the output end of the charging loop 1 outputs three-phase intersecting flow lines L1, L2, L3 and a central line N, which are all connected to the power supply plug 4, the output end of the charging loop 1 is connected to the 0.02-level electric energy metering module 3 in parallel, the 0.02-level electric energy metering module 3 comprises a front end plate, a sampling plate, a master control DSP, a 485 communication module and an electric energy pulse module, the master, front end plate and sampling board are connected, be equipped with current sensor and voltage sensor in the front end plate, current sensor respectively with three-phase AC line L1, L2, L3 is connected and is gathered current signal, voltage sensor respectively with three-phase AC line L1, L2, L3 and central line N are connected and are gathered voltage signal, still be equipped with the alternating-current electric pile check out test set simultaneously, set up electric energy pulse input interface and vehicle socket in the alternating-current electric pile check out test set, the electric energy pulse input interface is connected with the electric energy pulse module, vehicle socket and power plug 4 are connected.
During specific implementation, the 0.02-level electric energy metering module 3 measures three-phase current and voltage output by the charging loop 1 between the output end of the charging pile charging loop 1 and the power supply plug 4, and processes the three-phase current and the voltage to obtain charging electric energy, the accuracy levels of the measured current, voltage and electric energy values are all 0.02 level, the current, voltage and electric energy values of each phase measured by the 0.02-level electric energy metering module 3 are transmitted to the charging pile control module 2 through 485 communication, and the charging pile control module 2 transmits the data to the human-computer interaction interface 5 for display; meanwhile, the 0.02-level electric energy metering module 3 can output a standard electric energy pulse signal for the alternating-current charging pile detection device to collect, and a user can compare the output current, voltage and electric energy value of the charging pile displayed on the human-computer interaction interface 5 with the current, voltage and electric energy value measured by the alternating-current charging pile detection device to realize the traceability calibration of the corresponding quantity value.
As shown in fig. 3, the current sensor is a zero-flux transformer, the load impedance value of the current sensor is smaller than 1 ohm, and an I/V conversion circuit is provided, so that the acquired current value is converted into a voltage signal with a corresponding proportion, and the load impedance value of the zero-flux transformer is smaller than 1 ohm by using the "virtual short" characteristic of an OPA2277 operational amplifier, so that the precision of the conversion circuit is ensured, in the figure, I1 is changed into I2 after passing through the current sensor, I2 and I1 have a fixed proportional relationship, then, I2 passes through the I/V conversion circuit, the operational amplifier output voltage U is-I × R, a suitable value after conversion is obtained, and then the converted value is input to the sampling board.
As shown in fig. 4, the voltage sensor includes an amplifying circuit and a follower circuit connected to each other, the amplifying circuit is provided with an AD8221 precision instrument amplifier, the follower circuit is provided with an OP2277 operational amplifier, the structure is simple, and error introduction of other complicated links is avoided, wherein after the input voltage U1 passes through the precision instrument amplifier AD8221 with the gain of G times, the voltage is changed into U2, U2 is U1 × G, then the voltage passes through the follower circuit of the operational amplifier OP2277, and finally the voltage U3 is output, wherein U3 is U2.
As shown in fig. 5, the sampling board is provided with an a/D converter, the a/D converter is an 18-bit charge redistribution successive approximation type analog-to-digital converter, the model is AD7608, voltage signals U and U3 after conversion of the front end board are input to the a/D converter, and after quantization of the a/D converter, a digital signal is output and provided to the main control DSP module.
As shown in fig. 6, the main control DSP is used as an operation control unit of the 0.02-level electric energy metering module 3 to control electric energy pulse output, synchronous sampling of the sampling board, and communication of the 485 communication module, wherein the input terminal receives a digital signal converted by the sampling board, one terminal outputs an electric energy pulse signal to the electric energy pulse module, and the other terminal outputs a 485 signal to the 485 communication module.
As shown in fig. 7, the 485 communication module receives the TTL level output by the main control DSP, converts the TTL level into a 485 level specified by the RS485 protocol physical layer, and provides an external interface to implement communication with the charging pile control module, where the TTL level is input to the MAX485 chip through the input terminal, and the MAX485 chip is converted into the 485 level and output through the output terminal.
As shown in fig. 8, the power pulse module uses an NE555 chip to form a schmitt trigger, which converts the output signal of the main control DSP into a 5V pulse signal suitable for transmission, wherein the output signal of the main control DSP is input into the schmitt trigger through an input terminal, and then is converted into a 5V power pulse to be output through an output terminal.
The above-mentioned embodiments, further detailed description of the objects, technical solutions and advantages of the present invention, it should be understood that the above description is only the embodiments of the present invention, and is not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (8)
1. The novel alternating-current charging pile convenient for magnitude tracing is characterized by comprising a charging loop (1), a charging pile control module (2), a 0.02-level electric energy metering module (3), a power supply plug (4) and a human-computer interaction interface (5), wherein the charging loop (1), the 0.02-level electric energy metering module (3), the power supply plug (4) and the human-computer interaction interface (5) are electrically connected with the charging pile control module (2), the input end of the charging loop (1) is connected into an external three-phase four-wire alternating-current power grid, the output end of the charging loop (1) outputs three-phase intersecting flow lines L1, L2, L3 and a central line N which are connected into the power supply plug (4), meanwhile, the output end of the charging loop (1) is connected into the 0.02-level electric energy metering module (3) in parallel, the 0.02-level electric energy metering module (3) comprises a front end plate, a sampling plate, a master control DSP, a, the main control DSP is respectively connected with the sampling plate, the 485 communication module and the electric energy pulse module, the front end plate is connected with the sampling plate, a current sensor and a voltage sensor are arranged in the front end plate, the current sensor is respectively connected with three-phase alternating current lines L1, L2 and L3 to collect current signals, and the voltage sensor is respectively connected with three-phase alternating current lines L1, L2, L3 and a central line N to collect voltage signals.
2. The new type AC charging pile convenient for tracing magnitude according to claim 1, wherein said current sensor is a zero flux transformer, its load impedance value is less than 1 ohm, and is equipped with I/V conversion circuit.
3. The novel alternating-current charging pile facilitating magnitude tracing is characterized in that the voltage sensor comprises an amplifying circuit and a following circuit which are connected with each other, the amplifying circuit is provided with an AD8221 precision instrument amplifier, and the following circuit is provided with an OP2277 operational amplifier.
4. The novel alternating current charging pile facilitating magnitude tracing is characterized in that the sampling board is provided with an A/D converter, and the A/D converter is an 18-bit charge redistribution successive approximation type analog-to-digital converter with the model number of AD 7608.
5. The novel alternating-current charging pile convenient for magnitude tracing according to claim 1 or 4, wherein the main control DSP is a DSP processor and is provided with an input terminal and two output terminals, the input terminal is connected with an A/D converter to receive converted digital signals, and the two output terminals are respectively connected with a 485 communication module and an electric energy pulse module to output 485 signals and electric energy pulse signals.
6. The novel alternating-current charging pile convenient for magnitude tracing as claimed in claim 1, wherein the 485 communication module adopts a MAX485 chip, an input terminal of the MAX485 chip is connected with the main control DSP, and an output terminal of the MAX485 chip is connected with the charging pile control module.
7. The novel alternating-current charging pile convenient for magnitude traceability as claimed in claim 1, wherein the electric energy pulse module adopts NE555 chip to form a Schmitt trigger, and the input terminal of the electric energy pulse module is connected with the main control DSP.
8. The novel alternating-current charging pile convenient for magnitude traceability according to claim 5, wherein an alternating-current charging pile detection device is further arranged, an electric energy pulse input interface and a vehicle socket are arranged in the alternating-current charging pile detection device, the electric energy pulse input interface is connected with an electric energy pulse module, and the vehicle socket is connected with a power supply plug (4).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920825107.8U CN210234707U (en) | 2019-06-03 | 2019-06-03 | Novel alternating-current charging stake convenient to carry out quantity value traceability |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920825107.8U CN210234707U (en) | 2019-06-03 | 2019-06-03 | Novel alternating-current charging stake convenient to carry out quantity value traceability |
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| CN210234707U true CN210234707U (en) | 2020-04-03 |
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| CN201920825107.8U Active CN210234707U (en) | 2019-06-03 | 2019-06-03 | Novel alternating-current charging stake convenient to carry out quantity value traceability |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112009297A (en) * | 2020-10-26 | 2020-12-01 | 中国测试技术研究院电子研究所 | Charging pile electric energy detection traceability method and system |
| CN113183812A (en) * | 2021-05-08 | 2021-07-30 | 阳光电源股份有限公司 | Method and device for determining charging electric quantity and electronic equipment |
-
2019
- 2019-06-03 CN CN201920825107.8U patent/CN210234707U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112009297A (en) * | 2020-10-26 | 2020-12-01 | 中国测试技术研究院电子研究所 | Charging pile electric energy detection traceability method and system |
| CN112009297B (en) * | 2020-10-26 | 2021-03-09 | 中国测试技术研究院电子研究所 | Charging pile electric energy detection traceability method and system |
| CN113183812A (en) * | 2021-05-08 | 2021-07-30 | 阳光电源股份有限公司 | Method and device for determining charging electric quantity and electronic equipment |
| CN113183812B (en) * | 2021-05-08 | 2022-09-13 | 阳光电源股份有限公司 | Method and device for determining charging electric quantity and electronic equipment |
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