CN104007410A - Digital electric energy meter verifying device - Google Patents

Abstract

The invention introduces a digital electric energy meter verification device, which consists of a three-phase power source (1), a sampling module (2), a protocol conversion module (3), a standard electric energy meter (4), an error calculation module (5), a standard The digital electric energy meter (6) is composed. Wherein the output end of the three-phase power source (1) is connected in parallel with the input end of the sampling module (2) and the standard electric energy meter (4). The output terminal of the sampling module (2) is connected to the input terminal of the protocol conversion module (3). The output terminal of the protocol conversion module (3) is connected to the input terminal of the standard digital watt-hour meter (6) and leads to a connection with the peripheral device digital watt-hour meter (7) to be tested. The output end of the standard digital electric energy meter (6) is connected in parallel with the input end of the standard electric energy meter (4) and the error calculation module (5). The accuracy of the standard digital power source of the device can be traced to the traditional electric energy standard, and the value can be transferred.

Description

Digital Energy Meter Calibration Device

technical field

The invention belongs to the technical field of electrical engineering, and in particular relates to an improved calibration device for a digital electric energy meter.

Background technique

With the rapid development of smart grid technology, digital substations based on the IEC61850 standard will become the trend of substation construction. Its information collection, transmission processing and output process will all be digitized, intelligent equipment, communication network, model and communication protocol unification, and operation management automation. The promotion of digital substation technology has triggered a revolution in energy measurement technology. The digital metering method uses optical fiber channel for digital transmission, which effectively eliminates the secondary voltage drop and the analog/digital (A/D) conversion error of the analog electric energy meter, and improves the accuracy and stability of electric energy metering; therefore, Digital metering will become the development direction of electric energy metering.

The National Metrology Law stipulates that the gateway electric energy metering devices used for trade settlement must accept compulsory verification. In the traditional electronic energy metering system, the electromagnetic transformer outputs analog voltage and current signals, which are transmitted to the electric energy meter through the secondary cable. The electric energy meter converts the analog quantity into a digital pulse quantity, and then calculates a certain period of In this way, the traditional electronic energy metering system will bring a large measurement uncertainty. In the digital metering system, the electronic transformer outputs digital voltage and current signals, which are transmitted to the merging unit through optical fiber. The merging unit combines the voltage and current information into a data frame in a standardized format according to the IEC61850-9 standard, and the digital energy meter receives this data. Frame, directly conduct mathematical calculations to obtain electric energy. It can be seen that the working principle and input and output forms of electronic transformers and digital energy meters have undergone essential changes. Due to their poor reliability, traditional calibration equipment cannot be calibrated due to the lack of a complete digital measurement value transmission system. .

Contents of the invention

The technical problem to be solved by the present invention is to provide an improved digital electric energy meter verification device for the defects of poor reliability and lack of a complete digital measurement value transmission system existing in the existing digital electric energy meter verification technology.

The technical scheme of the present invention is, referring to accompanying drawing 1, the digital watt-hour meter verification device provided is as shown in Figure 1, and it is made of three-phase power source 1, sampling module 2, protocol conversion module 3, standard watt-hour meter 4, error The calculation module 5 and the standard digital electric energy meter 6 are connected in series. Wherein, the output end of the three-phase power source 1 is connected in parallel with the input end of the sampling module 2 and the input end of the standard electric energy meter 4 . The output end of the sampling module 2 is connected to the input end of the protocol conversion module 3 . The output end of the protocol conversion module 3 is connected to the input end of the standard digital energy meter 6 and leads out to the connection with the digital energy meter 7 to be tested. The output end of the standard digital energy meter 6 is connected in parallel with the input end of the standard electric energy meter 4 and the input end of the error calculation module 5 .

When the digital watt-hour meter calibration device thus constituted is in use, the connection line drawn from the output end of the protocol conversion module 3 is externally connected to the digital watt-hour meter of the peripheral device to be checked, and the output terminal of the digital watt-hour meter to be checked by the peripheral device is connected to The input terminal of the above-mentioned error calculation module 5 of the device can implement the detection and verification of the external digital electric energy meter 7 to be tested. During the detection and verification process, the sampling module 2 samples the voltage and current of the three-phase power source 1, and the sampling signal passes through the protocol conversion module 3 to obtain a standard digital power source whose output data conforms to the IEC61850-9-1/-9-2 standard. The output of the standard digital power source is divided into two routes: one route is transmitted to the digital energy meter 7 to be tested through framing, and the other route is transmitted to the standard digital energy meter 6 .

Therefore, by comparing the accumulated electric energy values of the digital electric energy meter under inspection and the standard digital electric energy meter, the error of the digital electric energy meter under inspection can be obtained. By comparing the accumulated electric energy of the standard digital electric energy meter with the measured electric energy of the standard electric energy meter, the error of the standard digital power source can be obtained.

The beneficial effects of the present invention are: the accuracy of the standard digital power source can be traced to the traditional electric energy standard, and the accuracy of the standard digital power source can be transferred in value;

Description of drawings

Fig. 1 is a structural block diagram of a specific embodiment of the digital electric energy meter calibration device of the present invention, marked as:

1—three-phase power source,

2—sampling module,

3—protocol conversion module,

4—Standard electric energy meter,

5—error calculation module,

6—Standard digital energy meter,

7—The checked digital energy meter.

Detailed ways

Referring to Fig. 1, Fig. 1 shows a specific embodiment of the digital electric energy meter calibration device of the present invention. In this embodiment, the three-phase power source 1 adopts a commercially available XL803 three-phase power source, and outputs an analog quantity of 3U3I; the sampling module 2 adopts a commercially available general-purpose AD module; the protocol conversion module 3 adopts a commercially available IEC61850 protocol converter; the standard electric energy meter 4 The commercially available 0.2s level DSSD331 three-phase electric energy meter is used; the error calculation module 5 adopts the commercially available DSP (BF531) module; and the standard digital electric energy meter 6 adopts the commercially available 0.2s level DSSD331-ME2 digital electric energy meter. The three-phase power source 1, the sampling module 2, the protocol conversion module 3, the standard electric energy meter 4, the error calculation module 5, and the standard digital electric energy meter 6 are connected in series according to the above-mentioned technical scheme with reference to the accompanying drawing 1 to form the present embodiment Calibration device for digital electric energy meter. Wherein, the output end of the three-phase power source 1 is connected in parallel with the input end of the sampling module 2 and the input end of the standard electric energy meter 4 . The output end of the sampling module 2 is connected to the input end of the protocol conversion module 3 . The output end of the protocol conversion module 3 is connected to the input end of the standard digital energy meter 6 and leads out to the connection with the digital energy meter 7 to be tested. The output end of the standard digital energy meter 6 is connected in parallel with the input end of the standard energy meter 4 and the input end of the error calculation module 5 .

Claims (1)

1. a digital watt-hour meter verification device is characterized in that: it consists of a three-phase power source (1), a sampling module (2), a protocol transformation module (3), a standard watt-hour meter (4), an error calculation module (5 ), a standard digital watt-hour meter (6) connected in series, wherein, the output terminal of the three-phase power source (1) is connected in parallel with the input terminal of the sampling module (2) and the input terminal of the standard watt-hour meter (4), and the sampling module The output end of (2) connects the input end of protocol transformation module (3), and the output end of described protocol transformation module (3) connects the input end of standard digital watt-hour meter (6) and draws and peripheral hardware is checked digital watt-hour meter ( 7), and the output terminal of the standard digital watt-hour meter (6) is connected in parallel with the input terminal of the standard watt-hour meter (4) and the input terminal of the error calculation module (5).