Charging post direct-current electric energy meter calibrating device

Abstract

The invention discloses a charging post direct-current electric energy meter calibrating device, which comprises a calibrating power supply, a data acquisition unit, a data processing unit and a human-computer interaction unit. The charging post direct-current electric energy meter calibrating device is a device which is characterized in that the calibrated direct-current electric energy meter is calibrated and corrected in a virtual power output method by the calibrating device on the basis of a real-time pulse comparison method. Two independent power supplies serve as a calibrating power supply. By aiming at the situations of higher rated current and high rated voltage of the calibrated direct-current electric energy meter, large dynamic range, high requirement on frequency response performance and the like, the metering performance of the calibrated direct-current electric energy meter can be comprehensively and accurately evaluated, and the charging post direct-current electric energy meter calibrating device is convenient for the electric energy metering characteristics to be traced to the superior national standard.

Description

technical field [0001] The invention relates to a verification device for a DC electric energy meter of a charging pile, in particular to an electric energy meter verification device for charging an on-board storage battery used in large and medium-sized electric vehicles, and belongs to the technical field of calibration, verification and detection of DC electric energy metering equipment. Background technique [0002] The on-board batteries used in large and medium-sized electric vehicles generally use DC charging. The voltage and current of the charging pile during charging are: (400~800)V / (0~500)A. The electric energy calculation is a special DC electric energy meter. Due to the high rated current and rated voltage of this type of electric energy meter, and the large range of current variation, the existing measurement and verification devices cannot effectively evaluate the performance of this type of electric energy meter. In addition, when the charging pile is chargin...

AI Technical Summary

Problems solved by technology

[0002] The on-board batteries used in large and medium-sized electric vehicles generally use DC charging. The voltage and current of the charging pile during charging are: (400~800)V / (0~500)A. The electric energy calculation is a special DC electric energy meter. Due to the high rated current and rated voltage of this type of electric energy meter, and the large range of current variation, the existing measurement and verification devices cannot effectively evaluate the performance of this type of electric energy meter. In addition, when the charging pile is charging, the current and voltage ranges are very wide, and there are ripples and impact peaks, which have high requirements for the dynamic range and frequency response of the electric energy meter. Correspondingly, the verification device for the DC electric energy meter of the charging pile , higher accuracy index is required to comprehensively and accurately evaluate the measurement performance of DC electric energy meters, and to facilitate the traceability of electric energy measurement characteristics to higher-level national standards

[0003] The known verification device for the DC electric energy meter of the electric vehicle charging pile adopts an equivalent conversion method for calibration, and its characteristics are: the equivalent voltage is used to replace the sampling voltage of the current port shunt of the electric energy meter, and the actual working current of the electric energy meter is simulated. The shortcoming of this method is that the equivalent voltage is used to replace the sampling voltage of the shunt, the shunt is separated from the electric energy meter, and the error caused by the measurement process of the shunt is ignored. The calibration data cannot truly reflect the actual working characteristics of the electric energy meter; and the test data needs to be manually recorded, and a large amount of data post-processing work is performed, which is not conducive to the accuracy and efficiency of the experimental process, and is not conducive to the timely provision of test data

There is also a real-time pulse comparison method to verify the meter device, such as the Chinese invention patent "A DC Electric Energy Meter Verification Device and Method" (application number: 201010565330.7 application date: 2010-11-25), including human-computer interaction interface, Main control module, voltage and current power amplifier module and measurement module, electric energy calculation module, standard pulse output interface and detected pulse input interface, the electric energy calculation module calculates and converts the standard pulse according to the measurement results of the voltage and current measurement module, and outputs it to the detected pulse Electric energy meter, the electric energy calculation module converts the electric energy input of the electric energy meter under inspection according to the pulse input of the electric energy meter under inspection, and compares it with the electric energy of the verification device, and calculates the electric energy error of the electric energy meter under inspection. The disadvantage of this device is: And the method has poor adaptability to the verification of the charging pile meter, and the verification of the dynamic range and frequency response of the electric energy meter cannot meet the requirements

[0004] On the other hand, in the existing known technology, for the verification of the electric energy meter of the charging pile, a DC power supply with relatively large power is used to input the voltage and current value required for the verification to the electric meter under inspection, and the output terminal of the electric meter under inspection is connected to the standard load, and then Equivalent conversion or real-time pulse comparison method is used for verification, so this method consumes a lot of power during verification

[0005] A device based on the real-time pulse comparison method, the verification device realizes the verification and calibration of the electric energy meter in the form of virtual power output, which has not been seen in existing patents or related technical literature reports

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