CN103630871B - Electronic electric energy meter dynamic characteristic test device - Google Patents

Abstract

The invention provides a dynamic characteristic testing device for an electronic electric energy meter, which includes a single chip microcomputer, a programmable logic control device, a voltage and current transformer, a signal sampling circuit, a thyristor control circuit, a pulse shaping circuit, a pulse counting circuit and a liquid crystal display circuit ; The three-phase steady-state voltage and current signal passes through the voltage-current transformer and the signal sampling circuit to generate a control signal with the same frequency as the three-phase steady-state voltage; the programmable logic device control signal is transmitted to the thyristor control circuit; the thyristor control The circuit generates three-phase dynamic power output to the external measured electric energy meter; the external measured electric energy meter obtains the electric energy value according to the measurement, and outputs electric energy pulses to the single-chip microcomputer; the single-chip computer calculates the dynamic error of the measured electric energy meter. The electronic electric energy meter dynamic characteristic testing device of the embodiment of the present invention realizes the measurement of the metering characteristic of the electric energy meter under dynamic load; discloses the test of the dynamic error characteristic start-up characteristic of the electronic electric energy meter under various dynamic load modes.

Description

Electronic Energy Meter Dynamic Characteristic Test Device

technical field

The invention relates to the field of electric energy meter testing, in particular to a dynamic characteristic testing device of an electronic electric energy meter.

Background technique

In recent years, with the continuous increase of dynamic loads in modern power systems, the problem of the reduction of electric energy metering values caused by dynamic load power users has become more and more prominent and important. For field-used electric energy meters, it is urgent to test the dynamic characteristics of electric energy metering. . Therefore, the test of the dynamic characteristics of the electric energy meter has become a new problem to be solved urgently.

In order to determine the dynamic error characteristics of the electric energy meter in practical application, the most effective method is to test the electric energy meter under the actual grid working conditions. However, under actual power grid conditions, the dynamic load current and power factor change drastically, so that the test excitation signal of the electric energy meter is not controllable. From the perspective of metrology, the measurement of the dynamic error of the electric energy meter is not repeatable, so it is not necessary The dynamic error characteristics of the electric energy meter can be repeatedly compared.

Contents of the invention

In view of the above problems, an embodiment of the present invention provides a device for testing the dynamic characteristics of an electronic electric energy meter, so as to solve the existing problem of testing the dynamic characteristics of electric energy meters.

In order to achieve the above purpose, the embodiment of the present invention provides a dynamic characteristic testing device of an electronic electric energy meter, including a single-chip microcomputer, a programmable logic control device, a voltage and current transformer, a signal sampling circuit, a thyristor control circuit, a pulse shaping circuit, a pulse A counting circuit and a liquid crystal display circuit; wherein, the voltage and current transformer is connected to the signal sampling circuit, the signal sampling circuit is connected to the programmable logic control device, and the programmable logic control device is connected to the thyristor control circuit, the pulse shaping circuit is connected to the pulse counting circuit, and the programmable logic control device, the pulse counting circuit and the liquid crystal display circuit are all connected to the single-chip microcomputer; the externally input three-phase voltage and current signals pass through the voltage and current transformer After summing the signal sampling circuit, a control signal with the same frequency as the three-phase steady-state voltage is generated; the programmable logic control device receives the control signal and controls the thyristor control circuit; the thyristor control circuit Generate dynamic power output to the external measured electric energy meter; the external measured electric energy meter obtains the electric energy value according to the dynamic power measurement, and outputs the electric energy pulse, which is transmitted to the pulse after being shaped and filtered by the pulse shaping circuit Counting circuit; after the pulse counting circuit counts the electric energy pulses output by the external measured electric energy meter, it is sent to the single-chip microcomputer; the single-chip microcomputer collects the output pulse of the standard electric energy meter, and calculates the dynamic state of the electric energy meter under test Error; the liquid crystal display circuit is used to display the dynamic error.

Further, in an embodiment, the signal sampling circuit is used to convert an analog signal into a digital signal for controlling a process.

Further, in one embodiment, the programmable logic control device is CPLD XC9536.

Further, in one embodiment, the single-chip microcomputer is an SST89E516RD2 chip.

Further, in one embodiment, the test device further includes a power supply module connected to the programmable logic control device and the single-chip microcomputer for providing power.

Further, in one embodiment, the test device further includes a watchdog circuit connected to the single-chip microcomputer for resetting the single-chip microcomputer.

The electronic electric energy meter dynamic characteristic testing device of the embodiment of the present invention is set up and uses CPLD control to produce dynamic load test excitation signal, realizes the measurement of electric energy meter metering characteristic under dynamic load; Utilizes the device of development and design, constructs electric energy meter and carries out dynamic characteristic The test reveals the test of the dynamic error characteristics of the electronic watt-hour meter in various dynamic load modes and the start-up characteristics.

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 creative work.

FIG. 1 is a schematic structural diagram of a testing device for dynamic characteristics of an electronic energy meter according to an embodiment of the present invention.

detailed description

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.

FIG. 1 is a schematic structural diagram of a testing device for dynamic characteristics of an electronic energy meter according to an embodiment of the present invention. As shown in the figure, the test device includes a single chip microcomputer 1, a programmable logic control device 2, a voltage and current transformer 3, a signal sampling circuit 4, a thyristor control circuit 5, a pulse shaping circuit 6, a pulse counting circuit 7 and a liquid crystal display Circuit 8; where,

The voltage and current transformer 3 is connected to the signal sampling circuit 4, the signal sampling circuit 4 is connected to the programmable logic control device 2, and the programmable logic control device 2 is connected to the thyristor control circuit 5, so The pulse shaping circuit 6 is connected to the pulse counting circuit 7 , and the programmable logic control device 2 , pulse counting circuit 7 and liquid crystal display circuit 8 are all connected to the single chip microcomputer 1 .

After the three-phase steady-state voltage and current signal input externally passes through the voltage-current transformer 3 and the signal sampling circuit 4, a control signal with the same frequency as the three-phase steady-state voltage is generated; the programmable logic control device 2 receives the Described control signal, controls described silicon controlled rectifier control circuit 5; Described silicon controlled rectifier control circuit 5 produces dynamic power output to the external electric energy meter under test; The dynamic power measurement of described external electric energy meter under test obtains electric energy value, And output electric energy pulse, after described pulse shaping circuit 6 carries out shaping and filtering, transmit to described pulse counting circuit 7; After described pulse counting circuit 7 counts the electric energy pulse output by described external measured electric energy meter, send to The single-chip microcomputer 1; the single-chip microcomputer 1 collects the output pulse of the standard electric energy meter, and calculates the dynamic error of the electric energy meter under test; the liquid crystal display circuit 8 is used to display the dynamic error.

In this embodiment, the signal sampling circuit 4 is used to convert the analog signal into a digital signal for controlling the process.

In this embodiment, the programmable logic control device 2 is a CPLD XC9536.

In this embodiment, the single-chip microcomputer 1 is a SST89E516RD2 chip.

In this embodiment, the test device further includes a watchdog circuit 9 connected to the single-chip microcomputer 1 for resetting the single-chip microcomputer 1 .

In this embodiment, the testing device further includes a power supply module 10 connected to the programmable logic control device 2 and the single-chip microcomputer 1 for providing power.

When using the above-mentioned dynamic characteristic testing device of the electric energy meter to carry out the error test, it is first necessary to establish a mathematical model of the dynamic load electric energy sequence excitation, and then measure the dynamic error on this basis. In the present invention, the OOK (On-Off-Key) on-off control method is used to convert the steady-state current signal into a dynamic load current signal, and the electric energy sequence excitation method is used to calculate the dynamic load electric energy of the electric energy meter. The above calculation method belongs to the present invention. It is well known to those skilled in the art, so it will not be repeated in the present invention.

The electronic electric energy meter dynamic characteristic testing device of the embodiment of the present invention is set up and uses CPLD control to produce dynamic load test excitation signal, realizes the dynamic characteristic measurement of electric energy meter; Use the device of development and design, set up experiment platform, carry out dynamic error to electric energy meter The test reveals the performance of the dynamic error of the electronic energy meter under various dynamic load modes.

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 (6)

1. An electronic energy meter dynamic characteristic testing device is characterized in that, said testing device comprises a single-chip microcomputer, a programmable logic control device, a voltage-current transformer, a signal sampling circuit, a thyristor control circuit, a pulse shaping circuit, a pulse Counting circuit and liquid crystal display circuit; wherein, The voltage and current transformer is connected to the signal sampling circuit, the signal sampling circuit is connected to the programmable logic control device, the programmable logic control device is connected to the thyristor control circuit, and the pulse shaping circuit is connected to the The pulse counting circuit, the programmable logic control device, the pulse counting circuit and the liquid crystal display circuit are all connected to the single-chip microcomputer; After the three-phase voltage and current signals input from the outside pass through the voltage and current transformer and the signal sampling circuit, a control signal with the same frequency as the three-phase steady-state voltage is generated; The programmable logic control device receives the control signal and controls the thyristor control circuit; The thyristor control circuit generates dynamic power output to an external electric energy meter to be tested; The external electric energy meter under test obtains an electric energy value according to the dynamic power measurement, and outputs electric energy pulses, which are transmitted to the pulse counting circuit after being shaped and filtered by the pulse shaping circuit; After the pulse counting circuit counts the electric energy pulses output by the external electric energy meter under test, the pulses are sent to the single chip microcomputer; The single-chip microcomputer collects the output pulse of the standard watt-hour meter, and calculates the dynamic error of the measured watt-hour meter; The liquid crystal display circuit is used to display the dynamic error; Wherein, when using the electronic electric energy meter dynamic characteristic testing device to carry out the error test, it includes establishing a mathematical model of the dynamic load electric energy sequence excitation, and on this basis, the measurement of the dynamic error is also included. The state current signal is converted into a dynamic load current signal, and the dynamic load electric energy of the electric energy meter is calculated by using the electric energy sequence excitation method. 2 . The device for testing the dynamic characteristics of an electronic energy meter according to claim 1 , wherein the signal sampling circuit is used for converting an analog signal into a digital signal for controlling a process. 3 . 3. The device for testing the dynamic characteristics of an electronic energy meter according to claim 1, wherein the programmable logic control device is a CPLD XC9536. 4. The device for testing the dynamic characteristics of an electronic energy meter according to claim 1, wherein the single-chip microcomputer is an SST89E516RD2 chip. 5. The device for testing the dynamic characteristics of the electronic energy meter according to claim 1, wherein the test device further comprises a power supply module connected to the programmable logic control device and the single-chip microcomputer for providing power. 6. The device for testing the dynamic characteristics of an electronic energy meter according to claim 1, wherein the test device further comprises a watchdog circuit connected to the single-chip microcomputer for resetting the single-chip microcomputer.