Dynamic error measurement device, system and dynamic error calibration method for electric energy meter

Abstract

The application discloses a kind of electric energy meter dynamic error measuring device, system and dynamic error calibration method.The measuring device includes small signal generation unit, test signal power amplification unit, measurement unit and calculation control unit;Small signal generation unit generates and outputs Uu small analog signal and Ui small analog signal to test signal power amplification unit according to the control of calculation control unit;Test signal power amplification unit carries out power amplification to Uu small analog signal and Ui small analog signal to obtain voltage test signal and current test signal, and outputs voltage test signal and current test signal to measurement unit;Measurement unit determines electric energy value according to voltage test signal and current test signal, and outputs electric energy value to calculation control unit.The measuring device provided in the application supports calibration unit to exist as independent component, reduces the cost and complexity of measuring device, solves the problem of lacking high dynamic accuracy standard meter when calibrating dynamic error of measuring device.

Description

Technical Field

[0001] This application relates to the field of electricity meter testing technology, specifically to an electricity meter dynamic error measurement device, system, and dynamic error calibration method. Background Technology

[0002] Detecting the dynamic error of a meter under test typically requires a measuring device to output an alternating current signal with varying amplitude, followed by measuring the meter's measurement error under the changing current signal (or power signal). To accurately measure the dynamic error of the meter under test, the measuring device itself generally needs to have a dynamic accuracy two levels higher than the meter under test. Obtaining the dynamic error index of the measuring device itself usually requires conducting dynamic traceability testing on the measuring device. The general testing method involves using a standard meter with a dynamic accuracy two levels higher than the measuring device, simultaneously measuring electrical energy with the measuring device under the dynamic test signal output by the measuring device, and then comparing the difference in measured electrical energy to obtain the dynamic error of the measuring device. Therefore, to conduct dynamic traceability testing of the measuring device using conventional methods, a standard meter with high dynamic accuracy must be used. However, currently available standard meters have their basic error indices obtained using energy meter calibration devices under steady-state sinusoidal signals, which do not include dynamic indices. Therefore, there is currently no usable standard meter with high dynamic accuracy. Summary of the Invention

[0003] To address the aforementioned issues, this application provides a dynamic error measurement device, system, and dynamic error calibration method for electricity meters, aiming to overcome or partially overcome the aforementioned technical problems.

[0004] The embodiments of this application adopt the following technical solutions:

[0005] In a first aspect, a dynamic error measurement device for an electricity meter is provided, comprising a small signal generation unit, a test signal power amplification unit, a measurement unit, and a calculation and control unit; wherein...

[0006] The small signal generation unit is used to generate Uu small analog signal and Ui small analog signal according to the control of the calculation and control unit, and output the Uu small analog signal and Ui small model signal to the test signal power amplification unit.

[0007] The test signal power amplification unit is used to amplify the Uu small analog signal to obtain a voltage test signal and the Ui small analog signal to obtain a current test signal, and output the voltage test signal and the current test signal to the measurement unit;

[0008] The measurement unit is used to determine the electrical energy value based on the received voltage test signal and current test signal, and output the electrical energy value to the calculation and control unit.

[0009] Optionally, the small signal generation unit is used to generate single-phase Uu small analog signal and single-phase Ui small analog signal according to the control of the calculation control unit, and output the single-phase Uu small analog signal and single-phase Ui small model signal to the test signal power amplification unit;

[0010] The test signal power amplification unit is used to amplify the single-phase Uu small analog signal to obtain the single-phase voltage test signal, and to amplify the single-phase Ui small analog signal to obtain the single-phase current test signal. The single-phase voltage test signal and the single-phase current test signal are then output to the measurement unit.

[0011] The measurement unit is used to determine the single-phase electrical energy value based on the received single-phase voltage test signal and single-phase current test signal, and output the single-phase electrical energy value to the calculation and control unit.

[0012] Optionally, the small signal generation unit is used to generate three-phase Uu small analog signals and three-phase Ui small analog signals according to the control of the calculation control unit, and output the three-phase Uu small analog signals and three-phase Ui small model signals to the test signal power amplification unit;

[0013] The test signal power amplification unit is used to amplify the three-phase Uu small analog signal to obtain the three-phase voltage test signal, amplify the three-phase Ui small analog signal to obtain the three-phase current test signal, and output the three-phase voltage test signal and the three-phase current test signal to the measurement unit.

[0014] The measurement unit is used to determine the three-phase electrical energy value based on the received three-phase voltage test signal and three-phase current test signal, and output the three-phase electrical energy value to the calculation and control unit.

[0015] Optionally, it also includes: a calibration unit, which comprises a calibration signal power amplification module and a current summing module; wherein,

[0016] The small signal generation unit is also used to generate a Ux small analog signal according to the control of the calculation control unit, and output the Ux small analog signal to the calibration signal power amplification module;

[0017] The calibration signal power amplification module is used to amplify the small analog signal Ux to obtain the current calibration signal, and output the current calibration signal to the current summing module.

[0018] The measurement unit is also used to output the received current test signal to the current summing module;

[0019] The current summing module is used to determine the combined current signal based on the received current calibration signal and current test signal.

[0020] Optionally, the number of phases of the Ux small analog signal is the same as that of the Uu and Ui small analog signals.

[0021] Secondly, a dynamic error measurement system for an electricity meter is provided, comprising: a standard meter and the aforementioned dynamic error measurement device for the electricity meter; wherein...

[0022] The standard meter is used to receive the voltage test signal and the combined current signal output by the dynamic error measuring device of the energy meter, and to determine the standard energy value based on the voltage test signal and the combined current signal; the steady-state accuracy of the standard meter is higher than the dynamic accuracy of the dynamic error measuring device of the energy meter.

[0023] The calculation control unit is also used to calibrate the dynamic error of the energy meter dynamic error measuring device based on the standard energy value and the energy value.

[0024] Thirdly, a dynamic error calibration method for a dynamic error measuring device of an energy meter is provided, implemented by the aforementioned dynamic error measuring system of the energy meter, the method comprising:

[0025] The Uu, Ui, and Ux small analog signals are generated under the control of the calculation and control unit.

[0026] The Uu and Ui analog signals are output to the test signal power amplification unit, so that the test signal power amplification unit amplifies the Uu analog signal to obtain a voltage test signal and amplifies the Ui analog signal to obtain a current test signal.

[0027] The voltage test signal and the current test signal are output to the measurement unit so that the measurement unit can determine the electrical energy value based on the voltage test signal and the current test signal.

[0028] The Ux small analog signal is output to the calibration signal power amplification module, so that the calibration signal power amplification module amplifies the Ux small analog signal to obtain the current calibration signal.

[0029] The current test signal and the current calibration signal are output to the current summing module so that the current summing module can determine the combined current signal based on the current test signal and the current calibration signal;

[0030] The voltage test signal and the combined current signal are output to the standard meter so that the standard meter can determine the standard energy value based on the voltage test signal and the combined current signal.

[0031] The dynamic error of the energy meter dynamic error measuring device is calibrated based on the energy value and the standard energy value.

[0032] Optionally, the Ux and Ui small analog signals form a mirror pair. The two small analog signals forming the mirror pair use a power frequency steady-state signal as a reference signal. The waveforms of the two small analog signals relative to the reference signal change continuously, and the ratio of the sum of the instantaneous values ​​of the two small analog signals to the instantaneous value of the reference signal at any given time remains constant.

[0033] Fourthly, a dynamic error measurement system for electricity meters is provided, comprising: the meter under test and the aforementioned dynamic error measurement device for electricity meters; wherein,

[0034] The meter under test is used to receive the voltage test signal and current test signal output by the dynamic error measurement device of the electricity meter, and to determine the value of the electrical energy to be tested based on the voltage test signal and current test signal.

[0035] The calculation control unit is also used to determine the dynamic error of the meter under test based on the electrical energy value to be tested and the electrical energy value.

[0036] Fifthly, a method for testing the dynamic error of an electricity meter using a dynamic error measuring device is provided, implemented by the aforementioned electricity meter dynamic error measuring system, the method comprising:

[0037] The Uu and Ui small analog signals are generated according to the control of the calculation and control unit.

[0038] The Uu and Ui analog signals are output to the test signal power amplification unit, so that the test signal power amplification unit amplifies the Uu analog signal to obtain a voltage test signal and amplifies the Ui analog signal to obtain a current test signal.

[0039] The voltage test signal and the current test signal are output to the measurement unit so that the measurement unit can determine the electrical energy value based on the voltage test signal and the current test signal.

[0040] The voltage test signal and the current test signal are output to the meter under test so that the meter under test can determine the energy value to be tested based on the voltage test signal and the current test signal.

[0041] The dynamic error of the meter under test is determined based on the electrical energy value and the electrical energy value to be tested.

[0042] The above-described technical solutions adopted in the embodiments of this application can achieve the following beneficial effects:

[0043] This application provides a dynamic error measurement device, system, and dynamic error calibration method for electricity meters. First, when calibrating the dynamic error of a measurement device using this device and system, a conventional electricity meter that only guarantees steady-state performance can be used as a standard meter, solving the current problem of a lack of high dynamic accuracy standard meters. Second, in terms of hardware architecture, the calibration unit can exist as an independent component, allowing multiple electricity meter dynamic error measurement devices to share a calibration unit, thereby reducing the cost and complexity of dynamic error calibration for multiple electricity meter dynamic error measurement devices. Attached Figure Description

[0044] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0045] Figure 1 A schematic diagram of the structure of a dynamic error measuring device for an energy meter according to an embodiment of this application is shown.

[0046] Figure 2 A schematic diagram of the structure of a dynamic error measuring device for an energy meter according to another embodiment of this application is shown;

[0047] Figure 3 This invention provides a schematic diagram of the structure of a current summing module of a dynamic error measuring device for an energy meter according to another embodiment of the present application.

[0048] Figure 4 A schematic diagram of the structure of a dynamic error measurement system for an energy meter according to an embodiment of this application is shown.

[0049] Figure 5 A flowchart illustrating a dynamic error calibration method for an energy meter dynamic error measuring device according to an embodiment of this application is shown.

[0050] Figure 6 The diagram shows the waveforms of phase a small analog signal Uu, phase a small analog signal Ui, and phase a small analog signal Ux during dynamic error calibration of a dynamic error measuring device for an energy meter according to an embodiment of this application.

[0051] Figure 7 A schematic diagram of the structure of a dynamic error measurement system for an energy meter according to another embodiment of this application is shown;

[0052] Figure 8 A flowchart illustrating a method for testing dynamic error using a dynamic error measuring device for an electricity meter according to another embodiment of this application is shown. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0054] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0055] The present application aims to provide a dynamic error measurement device, system, and dynamic error calibration method for electricity meters. When calibrating the dynamic error of the electricity meter dynamic error measurement device, a conventional electricity meter that only guarantees steady-state performance can be used as a standard meter, thus solving the problem of the lack of high dynamic accuracy standard meters for current dynamic error calibration of measurement devices. In terms of hardware architecture, the calibration unit can exist as an independent component, allowing multiple electricity meter dynamic error measurement devices to share the calibration unit, thereby reducing the cost and complexity of dynamic error calibration for multiple electricity meter dynamic error measurement devices.

[0056] An embodiment of this application provides a dynamic error measuring device 100 for an energy meter, including a small signal generation unit 101, a test signal power amplification unit 102, a measurement unit 103, and a calculation control unit 104. The small signal generation unit 101 generates a Uu small analog signal and a Ui small analog signal according to the control of the calculation control unit 104, and outputs the Uu and Ui small analog signals to the test signal power amplification unit 102. The test signal power amplification unit 102 amplifies the Uu small analog signal to obtain a voltage test signal and amplifies the Ui small analog signal to obtain a current test signal, and outputs the voltage and current test signals to the measurement unit 103. The measurement unit 103 determines the energy value based on the received voltage and current test signals and outputs the energy value to the calculation control unit 104.

[0057] The calculation and control unit 104 plays the following roles in the dynamic error measurement device 100 of the electricity meter: First, the calculation and control unit 104 enables human-machine interaction, that is, the user sends commands to the calculation and control unit 104 to control the small signal generation unit 101 to generate and output Uu and Ui small analog signals. Second, the calculation and control unit 104 enables data transmission, including receiving the electrical energy value output by the measurement unit 103 in the form of electrical energy pulses.

[0058] The dynamic error measuring device 100 for the electricity meter can be a single-phase measuring device. A small signal generation unit 101 generates single-phase Uu and single-phase Ui small analog signals according to the control of the calculation control unit 104, and outputs these signals to the test signal power amplification unit 102. The test signal power amplification unit 102 amplifies the single-phase Uu small analog signal to obtain a single-phase voltage test signal and amplifies the single-phase Ui small analog signal to obtain a single-phase current test signal, and outputs both signals to the measurement unit 103. The measurement unit 103 determines the energy value based on the received single-phase voltage and current test signals and outputs the energy value to the calculation control unit 104.

[0059] The dynamic error measuring device 100 for the electricity meter can also be a three-phase measuring device. The small signal generation unit 101 generates three-phase Uu and three-phase Ui small analog signals according to the control of the calculation control unit 104, and outputs these signals to the test signal power amplification unit 102. The test signal power amplification unit 102 amplifies the three-phase Uu small analog signals to obtain three-phase voltage test signals and amplifies the three-phase Ui small analog signals to obtain three-phase current test signals, then outputs both signals to the measurement unit 103. The measurement unit 103 determines the energy value based on the received three-phase voltage and current test signals and outputs the energy value to the calculation control unit 104.

[0060] Figure 1 A dynamic error measuring device 100 for an electricity meter according to an embodiment of this application is shown. The following is a detailed description of the dynamic error measuring device 100 for a three-phase electricity meter as an example.

[0061] like Figure 1 As shown, the small signal generation unit 101 is connected to the calculation control unit 104 via data line A. Under the control of the calculation control unit 104, it generates three-phase Uu small analog signals and three-phase Ui small analog signals. The output interfaces Uua, Uub, and Uuc of the small signal generation unit 101 output the Uu small analog signals for phase a, phase b, and phase c, respectively, and the output interfaces Uia, Uib, and Uic output the Ui small analog signals for phase a, phase b, and phase c, respectively.

[0062] The test signal power amplification unit 102 first receives the three-phase Uu and three-phase Ui analog signals through the corresponding terminals of its input interface. The three-phase Uu analog signals are amplified to obtain three-phase voltage test signals, which are then output as phase a, phase b, phase c, and neutral point voltage test signals via the output interfaces Ua, Ub, Uc, and Un of the test signal power amplification unit 102. The three-phase Ui analog signals are amplified to obtain three-phase current test signals, which are then output as phase a, phase b, phase c, and neutral point voltage test signals via the output interface Ia of the test signal power amplification unit 102. + Ia - The output of phase a current test signal is transmitted through the output interface Ib. + Ib - The output of phase b current test signal is transmitted through the output interface IC. + Ic - The terminal outputs the c-phase current test signal.

[0063] The three-phase voltage test signal and three-phase current test signal output by the test signal power amplification unit 102 are connected in parallel to the corresponding terminals of the voltage input interface and the current input interface of the measurement unit 103. The measurement unit 103 is connected to the calculation control unit 104 via data line B. The measurement unit 103 measures the electrical energy value based on the voltage test signal and the current test signal, and outputs the electrical energy value as an electrical energy pulse via the electrical energy pulse 1 signal line to the calculation control unit 104.

[0064] Another embodiment of this application provides a dynamic error measuring device 200 for an energy meter, which, based on the dynamic error measuring device 100 of the above embodiment, further includes: a calibration unit 105, which includes a calibration signal power amplification module 1051 and a current summing module 1052. The small signal generation unit 101 is further configured to generate a small analog signal Ux according to the control of the calculation control unit 104, and output the Ux small analog signal to the calibration signal power amplification module 1051. The calibration signal power amplification module 1051 is configured to amplify the Ux small analog signal to obtain a current calibration signal, and output the current calibration signal to the current summing module 1052. The measurement unit 103 is further configured to output the received current test signal to the current summing module 1052. The current summing module 1052 is configured to determine a combined current signal based on the received current calibration signal and current test signal.

[0065] As an optional implementation, the Ux small analog signal has the same number of phases as the Uu and Ui small analog signals. That is, when the energy meter dynamic error measuring device 100 is a single-phase measuring device (the Uu and Ui small analog signals are single-phase signals), the Ux small analog signal is a single-phase Ux small analog signal; when the energy meter dynamic error measuring device 100 is a three-phase measuring device (the Uu and Ui small analog signals are three-phase signals), the Ux small analog signal is a three-phase Ux small analog signal.

[0066] When the dynamic error measuring device 200 of the electricity meter is a single-phase measuring device, the small signal generation unit 101 is also used to generate a single-phase Ux small analog signal according to the control of the calculation control unit 104, and output the single-phase Ux small analog signal to the calibration signal power amplification module 1051. The calibration signal power amplification module 1051 is used to amplify the single-phase Ux small analog signal to obtain a single-phase current calibration signal, and output the single-phase current calibration signal to the current summing module 1052. The measuring unit 103 is also used to output the received single-phase current test signal to the current summing module 1052. The current summing module 1052 is used to determine the single-phase combined current signal based on the received single-phase current calibration signal and single-phase current test signal.

[0067] When the energy meter dynamic error measuring device 200 is a three-phase measuring device, the small signal generation unit 101 is also used to generate three-phase Ux small analog signals according to the control of the calculation control unit 104, and output the three-phase Ux small analog signals to the calibration signal power amplification module 1051. The calibration signal power amplification module 1051 is used to amplify the three-phase Ux small analog signals to obtain three-phase current calibration signals, and output the three-phase current calibration signals to the current summing module 1052. The measuring unit 103 is also used to output the received three-phase current test signals to the current summing module 1052. The current summing module 1052 is used to determine the three-phase combined current signal based on the received three-phase current calibration signals and three-phase current test signals.

[0068] Figure 2 A dynamic error measuring device 200 for an electricity meter according to another embodiment of this application is shown. Figure 3 A schematic diagram of the current summing module 1052 of the dynamic error measuring device for an energy meter according to another embodiment of this application is shown. The following is a detailed description using the three-phase dynamic error measuring device for an energy meter 200 as an example.

[0069] like Figure 2As shown, the small signal generation unit 101 is connected to the calculation control unit 104 via data line A. Under the control of the calculation control unit 104, it generates three-phase Uu small analog signals, three-phase Ui small analog signals, and three-phase Ux small analog signals. The output interfaces Uua, Uub, and Uuc of the small signal generation unit 101 output the Uu small analog signals for phases a, b, and c, respectively; the output interfaces Uia, Uib, and Uic output the Ui small analog signals for phases a, b, and c, respectively; and the output interfaces Uxa, Uxb, and Uxc output the Ux small analog signals for phases a, b, and c, respectively.

[0070] The test signal power amplification unit 102 first receives the three-phase Uu and three-phase Ui analog signals through the corresponding terminals of its input interface. The three-phase Uu analog signals are amplified to obtain three-phase voltage test signals, which are then output as phase a, phase b, phase c, and neutral point voltage test signals via the output interfaces Ua, Ub, Uc, and Un of the test signal power amplification unit 102. The three-phase Ui analog signals are amplified to obtain three-phase current test signals, which are then output as phase a, phase b, phase c, and neutral point voltage test signals via the output interface Ia of the test signal power amplification unit 102. + Ia - The output of phase a current test signal is transmitted through the output interface Ib. + Ib - The output of phase b current test signal is transmitted through the output interface IC. + Ic - The terminal outputs the c-phase current test signal.

[0071] The calibration signal power amplification module 1051 first receives the three-phase Ux small analog signal through the corresponding terminals of its input interface. The three-phase Ux small analog signal is then amplified to obtain the three-phase current calibration signal. This signal is then output through the Ixa interface of the calibration signal power amplification module 1051. + Ixa - The output phase a current calibration signal is sent to the output interface Ixb. + 、Ixb - The output b-phase current calibration signal is sent to the output interface Ixc. + 、Ixc - The terminal outputs a c-phase current calibration signal.

[0072] The three-phase voltage test signals output by the test signal power amplification unit 102 are connected in parallel to the corresponding terminals of the voltage input interface of the measurement unit 103. The three-phase current test signals output by the test signal power amplification unit 102 are first connected to the corresponding terminals of the current input interface of the measurement unit 103, and then connected to the corresponding terminals of the current input interface of the current summing module 1052 via the corresponding terminals of the current output interface of the measurement unit 103. The three-phase current calibration signals output by the calibration signal power amplification module 1051 are respectively output to the corresponding terminals of the current input interface of the current summing module 1052.

[0073] Combination Figure 3 As shown, the current summing module 1052 receives a three-phase current calibration signal and a three-phase current test signal. It adds each phase of the three-phase current calibration signal and the three-phase current test signal in phase to obtain a combined three-phase current signal. The current input interface Ia of the current summing module 1052... + Ia - The terminal receives the phase a current test signal and Ixa. + Ixa - The phase a current calibration signal received by the terminal is combined into Ija through a precision current transformer. + Ija - The terminal outputs the phase a combined current signal; the current input interface Ib of the current summing module 1052. + Ib - The terminal receives the b-phase current test signal and Ixb + 、Ixb - The b-phase current calibration signal received by the terminal is combined into Ijb through a precision current transformer. + Ijb - The terminal outputs the phase b combined current signal; the current input interface Ic of the current summing module 1052. + Ic - The c-phase current test signal and Ixc received by the terminal + 、Ixc - The c-phase current calibration signal received by the terminal is combined into Ijc by a precision current transformer. + Ijc - The c-phase combined current signal is output from the terminal.

[0074] The measurement unit 103 is connected to the calculation control unit 104 via data line B. The measurement unit 103 measures the electrical energy value based on the voltage test signal and the current test signal, and outputs the electrical energy value to the calculation control unit 104 in the form of electrical energy pulses via the electrical energy pulse 1 signal line.

[0075] The above-mentioned Uu small analog signal, Ui small analog signal and Ux small analog signal are generated in the same way, and are the same as the technology used in existing dynamic measurement devices for electricity meters. No specific examples will be given here. In addition, the test signal power amplification unit 102 and the calibration signal power amplification module 1051 are implemented in the same way, and are the same as the technology used in existing dynamic measurement devices for electricity meters. No specific examples will be given here.

[0076] Figure 4 An embodiment of the present application illustrates a dynamic error measurement system for an energy meter. This system can be used to implement a dynamic error calibration method for an energy meter dynamic error measurement device, including a standard meter 400 and the aforementioned energy meter dynamic error measurement device 200. The standard meter 400 receives voltage test signals and combined current signals output from the energy meter dynamic error measurement device 200, and determines a standard energy value based on the voltage test signals and combined current signals. The steady-state accuracy of the standard meter 400 is higher than the dynamic accuracy of the energy meter dynamic error measurement device 200. The calculation control unit 104 is further used to calibrate the dynamic error of the energy meter dynamic error measurement device 200 based on the standard energy value and the energy value.

[0077] In this system, the voltage test signal obtained by the test signal power amplification unit 102 is output to the corresponding terminal of the voltage input interface of the standard meter 400, in addition to being output to the measurement unit 103. The combined current signal output by the current summing module 1052 is output to the corresponding terminal of the current input interface of the standard meter 400.

[0078] When the dynamic error measuring device 200 of the energy meter is a three-phase measuring device, the four terminals Ua, Ub, Uc and Un of the voltage output interface of the test signal power amplification unit 102 output voltage test signals for phase a, phase b, phase c and neutral point respectively, which are connected in parallel to the corresponding terminals of the voltage input interface of the standard meter 400; the current summing module 1052 connects to Ija + Ija - The terminal outputs the combined current signal of phase a to the corresponding terminal of the current input interface of the standard meter 400, via Ijb. + Ijb - The terminal outputs the phase b combined current signal to the corresponding terminal of the current input interface of the standard meter 400, via Ijc. + Ijc - The terminal outputs the C-phase combined current signal to the corresponding terminal of the current input interface of the standard meter 400.

[0079] The standard meter 400 determines the standard energy value based on the received voltage test signal and combined current signal, and outputs it to the calculation and control unit 104 via the energy pulse 2 signal line. The calculation and control unit 104 calibrates the dynamic error of the energy meter dynamic error measuring device 200 based on the standard energy value and the energy value.

[0080] As a preferred embodiment, the steady-state accuracy of the standard meter 400 is two levels higher than the dynamic accuracy of the energy meter dynamic error measuring device 200.

[0081] As an optional implementation, the dynamic error calibration of the energy meter dynamic error measuring device 200 can also be achieved through an external error calculation platform. When using an error calculation platform, the calculation control unit 104 no longer undertakes the function of calibrating the dynamic error of the energy meter dynamic error measuring device 200, but instead outputs the energy value to the error calculation platform; the standard meter 400 also no longer outputs the standard energy value to the calculation control unit 104, but instead also outputs the standard energy value to the error calculation platform, which then calibrates the dynamic error of the energy meter dynamic error measuring device 200 based on the energy value and the standard energy value.

[0082] Figure 5 This diagram illustrates a flow chart of a dynamic error calibration method for an energy meter dynamic error measuring device 200 according to an embodiment of this application. The dynamic error calibration method comprises... Figure 4 The illustrated dynamic error measurement system for electricity meters is implemented. The method includes:

[0083] Step S501: Generate Uu small analog signal, Ui small analog signal and Ux small analog signal according to the control of the calculation control unit 104;

[0084] Step S502: Output the Uu small analog signal and the Ui small analog signal to the test signal power amplification unit 102, so that the test signal power amplification unit 102 amplifies the Uu small analog signal to obtain a voltage test signal and amplifies the Ui small analog signal to obtain a current test signal.

[0085] Step S503: Output the voltage test signal and the current test signal to the measurement unit 103 so that the measurement unit 103 can determine the electrical energy value based on the voltage test signal and the current test signal;

[0086] Step S504: Output the Ux small analog signal to the calibration signal power amplification module 1051 so that the calibration signal power amplification module 1051 amplifies the Ux small analog signal to obtain a current calibration signal.

[0087] Step S505: Output the current test signal and the current calibration signal to the current summing module 1052 so that the current summing module 1052 determines the merged current signal based on the current test signal and the current calibration signal.

[0088] Step S506: Output the voltage test signal and the combined current signal to the standard meter 400 so that the standard meter 400 can determine the standard energy value based on the voltage test signal and the combined current signal.

[0089] Step S507: Calibrate the dynamic error of the energy meter dynamic error measuring device 200 according to the energy value and the standard energy value.

[0090] As an optional implementation, the signal model of the Uu small analog signal, the Ui small analog signal, and the Ux small analog signal is set by the calculation control unit 104, and the Uu small analog signal, the Ui small analog signal, and the Ux small analog signal are generated based on the signal model, so that the dynamic error measuring device 200 of the energy meter outputs a voltage test signal and a combined current signal that are consistent with the set signal model, which are used as input signals for the standard meter 400 to measure.

[0091] As an optional implementation, the Ux and Ui small analog signals form a mirror pair. Using a power frequency steady-state signal as a reference signal, the waveforms of the two small analog signals relative to the reference signal continuously change, and the ratio of the sum of the instantaneous values ​​of the two small analog signals to the instantaneous value of the reference signal at any given moment remains constant. The power frequency steady-state signal refers to a power frequency sinusoidal signal or a power frequency steady-state distorted signal whose amplitude, frequency, and phase remain constant. The power frequency steady-state distorted signal contains the power frequency fundamental signal and its finite number of harmonic signals.

[0092] The following section will describe in detail the signal generated by the small signal generation unit 101, taking the dynamic error measuring device 200 of the electricity meter as an example of a three-phase measuring device.

[0093] Equations (1), (4), and (7) are mathematical expressions for the small analog signals Uu in phases a, b, and c, respectively; Equations (2), (5), and (8) are mathematical expressions for the small analog signals Ui in phases a, b, and c, respectively; Equations (3), (6), and (9) are mathematical expressions for the small analog signals Ux in phases a, b, and c, respectively.

[0094]

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103] Using phase a Ux small analog signal U xa (t) and phase a Ui small analog signal U ia Taking (t) as an example, we can illustrate the mirror transformation requirements it meets. xa (t) signal and U ia The (t) signal constitutes a mirror image of phase a. These two signals are the power frequency steady-state signal. As a reference signal, these two signals therefore have the following characteristics:

[0104] First, as can be seen from equations (2) and (3), the two signals are actually two modulated signals formed by the reference signal after being modulated by two amplitude modulation functions 0.25·sin(2π·5·t+0) and -0.25·sin(2π·5·t+0). Therefore, the waveforms of the two signals are constantly changing relative to the waveform of the reference signal.

[0105] Second, because Therefore, at any given moment, the sum of the instantaneous values ​​of these two signals, and the sum of the instantaneous values ​​of the reference signal at that moment, are equal to the sum of the instantaneous values ​​of the reference signal at that moment. The ratio of the instantaneous values ​​is always 2 and remains unchanged.

[0106] Figure 6 The waveforms of the a-phase Uu, a-phase Ui, and a-phase Ux small analog signals during the dynamic error calibration of the energy meter dynamic error measuring device 200 are shown. The corresponding waveforms of phase b are identical to those of phase a, except for an initial phase difference of -120°; the corresponding waveforms of phase c are also identical to those of phase a, except for an initial phase difference of 120°. The mirror transformation requirements for phase b and phase c signals are similar to those for phase a, and will not be elaborated further here.

[0107] As an optional implementation method, Figure 3 Taking the current summing unit 1052 shown as an example, the difference between twice the value of the electrical energy and the standard electrical energy value is compared to obtain the dynamic error of the dynamic error measuring device 200 of the electricity meter.

[0108] When using the above-mentioned dynamic error measurement system for electricity meters to calibrate the dynamic error of the measuring device, a conventional electricity meter that only guarantees steady-state performance can be used as the standard meter, which solves the problem of the current lack of high dynamic accuracy standard meters.

[0109] Figure 7 Another embodiment of the present application illustrates a dynamic error measurement system for an electricity meter. This system can be used to implement a method for testing the dynamic error of an electricity meter dynamic error measuring device, including: a meter under test 700 and the aforementioned electricity meter dynamic error measuring device 100. The meter under test 700 is used to receive voltage test signals and current test signals output by the electricity meter dynamic error measuring device 100, and determine the energy value to be tested based on the voltage test signals and current test signals. The calculation control unit 104 is further used to determine the dynamic error of the meter under test based on the energy value to be tested and the energy value.

[0110] In this system, the voltage test signal obtained by the test signal power amplification unit 102 is output to the corresponding terminal of the voltage input interface of the meter under test 700, in addition to being output to the measurement unit 103. The current test signal obtained by the test signal power amplification unit 102 is first connected to the corresponding terminal of the current input interface of the measurement unit 103, and then connected to the corresponding terminal of the current input interface of the meter under test 700 through the corresponding terminal of the current output interface of the measurement unit 103.

[0111] When the dynamic error measuring device 100 of the energy meter is a three-phase measuring device, the four terminals Ua, Ub, Uc, and Un of the voltage output interface of the test signal power amplification unit 102 output voltage test signals for phase a, phase b, phase c, and the neutral point, respectively, which are connected in parallel to the corresponding terminals of the voltage input interface of the meter under test 700. The current output interface Ia of the test signal power amplification unit 102... + Ia - The terminal is connected in series to output the phase a current test signal to the measurement unit 103 and the meter under test 700; Ib + Ib - The terminal is connected in series to output the phase b current test signal to the measurement unit 103 and the meter under test 700; Ic + Ic - The terminal is connected in series to output the c-phase current test signal to the measurement unit 103 and the meter under test 700.

[0112] The meter under test 700 determines the energy value to be tested based on the voltage test signal and current test signal it receives, and outputs it to the calculation and control unit 104 through the energy pulse 3 signal line. The calculation and control unit 104 determines the dynamic error of the meter under test 700 based on the energy value to be tested and the energy value.

[0113] Figure 8This illustration shows a flowchart of a method for testing dynamic errors using a dynamic error measuring device 100 for an electricity meter according to another embodiment of this application. The method for testing dynamic errors is... Figure 7 The illustrated dynamic error measurement system for electricity meters is implemented. The method includes:

[0114] Step S801: Generate Uu small analog signal and Ui small analog signal according to the control of the calculation control unit 104;

[0115] Step S802: Output the Uu small analog signal and the Ui small analog signal to the test signal power amplification unit 102, so that the test signal power amplification unit 102 amplifies the Uu small analog signal to obtain a voltage test signal and amplifies the Ui small analog signal to obtain a current test signal.

[0116] Step S803: Output the voltage test signal and the current test signal to the measurement unit 103 so that the measurement unit 103 can determine the electrical energy value based on the voltage test signal and the current test signal;

[0117] Step S804: Output the voltage test signal and the current test signal to the meter under test 700 so that the meter under test 700 can determine the energy value to be tested based on the voltage test signal and the current test signal.

[0118] Step S805: Determine the dynamic error of the meter under test 700 based on the electrical energy value and the electrical energy value to be tested.

[0119] Because the dynamic error measuring device for electricity meters supports the calibration unit 105 as an independent component in its hardware architecture, the calibration unit is included when calibrating the dynamic error of the dynamic error measuring device for electricity meters. When using the dynamic error measuring device for electricity meters to test the dynamic error of the meter under test, the calibration unit does not need to be used. This allows multiple dynamic error measuring devices for electricity meters to share the calibration unit, reducing the cost and complexity of the dynamic error measuring device for electricity meters.

[0120] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0121] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can 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.) containing computer-usable program code.

[0122] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A dynamic error measurement system for an electricity meter, characterized in that, include: A standard meter and a dynamic error measuring device for electricity meters; the dynamic error measuring device for electricity meters includes a small signal generation unit, a test signal power amplification unit, a measurement unit, and a calculation and control unit; wherein, The small signal generation unit is used to generate Uu small analog signal and Ui small analog signal according to the control of the calculation control unit, and output the Uu small analog signal and Ui small analog signal to the test signal power amplification unit; The test signal power amplification unit is used to amplify the Uu small analog signal to obtain a voltage test signal, amplify the Ui small analog signal to obtain a current test signal, and output the voltage test signal and the current test signal to the measurement unit. The measurement unit is used to determine the electrical energy value based on the received voltage test signal and the current test signal, and output the electrical energy value to the calculation and control unit; It also includes: a calibration unit, which comprises a calibration signal power amplification module and a current summing module; wherein, The small signal generation unit is also used to generate a Ux small analog signal according to the control of the calculation control unit, and output the Ux small analog signal to the calibration signal power amplification module; The calibration signal power amplification module is used to amplify the Ux small analog signal to obtain a current calibration signal, and output the current calibration signal to the current summing module; The measurement unit is also used to output the received current test signal to the current summing module; The current summing module is used to determine the merged current signal based on the received current calibration signal and the current test signal; The standard meter is used to receive the voltage test signal and the combined current signal output by the dynamic error measuring device of the energy meter, and to determine the standard energy value based on the voltage test signal and the combined current signal; the steady-state accuracy of the standard meter is higher than the dynamic accuracy of the dynamic error measuring device of the energy meter. The calculation and control unit is used to calibrate the dynamic error of the energy meter dynamic error measuring device according to the standard energy value and the energy value. In the hardware architecture of the energy meter dynamic error measurement device, the calibration unit is an independent component.

2. The dynamic error measurement system for electricity meters according to claim 1, characterized in that, The small signal generation unit is used to generate a single-phase Uu small analog signal and a single-phase Ui small analog signal according to the control of the calculation and control unit, and output the single-phase Uu small analog signal and the single-phase Ui small analog signal to the test signal power amplification unit. The test signal power amplification unit is used to amplify the single-phase Uu small analog signal to obtain a single-phase voltage test signal, amplify the single-phase Ui small analog signal to obtain a single-phase current test signal, and output the single-phase voltage test signal and the single-phase current test signal to the measurement unit. The measurement unit is used to determine the single-phase electrical energy value based on the received single-phase voltage test signal and the single-phase current test signal, and output the single-phase electrical energy value to the calculation and control unit.

3. The dynamic error measurement system for electricity meters according to claim 1, characterized in that, The small signal generation unit is used to generate three-phase Uu small analog signals and three-phase Ui small analog signals according to the control of the calculation and control unit, and output the three-phase Uu small analog signals and three-phase Ui small analog signals to the test signal power amplification unit; The test signal power amplification unit is used to amplify the power of the three-phase Uu small analog signal to obtain a three-phase voltage test signal, amplify the power of the three-phase Ui small analog signal to obtain a three-phase current test signal, and output the three-phase voltage test signal and the three-phase current test signal to the measurement unit. The measurement unit is used to determine the three-phase electrical energy value based on the received three-phase voltage test signal and the three-phase current test signal, and output the three-phase electrical energy value to the calculation and control unit.

4. The dynamic error measurement system for electricity meters according to claim 1, characterized in that, The Ux small analog signal has the same number of phases as the Uu small analog signal and the Ui small analog signal.

5. A method for calibrating the dynamic error of an energy meter dynamic error measuring device, characterized in that, The method is implemented by the dynamic error measurement system for electricity meters according to any one of claims 1-4, and includes: The Uu, Ui, and Ux small analog signals are generated under the control of the calculation and control unit. The Uu small analog signal and the Ui small analog signal are output to the test signal power amplification unit, so that the test signal power amplification unit amplifies the Uu small analog signal to obtain a voltage test signal and amplifies the Ui small analog signal to obtain a current test signal. The voltage test signal and the current test signal are output to the measurement unit so that the measurement unit determines the electrical energy value based on the voltage test signal and the current test signal; The Ux small analog signal is output to the calibration signal power amplification module, so that the calibration signal power amplification module amplifies the Ux small analog signal to obtain a current calibration signal. The current test signal and the current calibration signal are output to the current summing module, so that the current summing module determines the combined current signal based on the current test signal and the current calibration signal; The voltage test signal and the combined current signal are output to a standard meter so that the standard meter determines a standard energy value based on the voltage test signal and the combined current signal. The dynamic error of the energy meter dynamic error measuring device is calibrated based on the energy value and the standard energy value.

6. The dynamic error calibration method for the dynamic error measuring device of an electricity meter according to claim 5, characterized in that, The Ux and Ui small analog signals form a mirror pair. The two small analog signals forming the mirror pair use a power frequency steady-state signal as a reference signal. The waveforms of the two small analog signals change continuously relative to the reference signal, and the ratio of the sum of the instantaneous values ​​of the two small analog signals to the instantaneous value of the reference signal at any given time remains constant.

7. A dynamic error measurement system for an electricity meter, characterized in that, include: A dynamic error measuring device for the tested meter and the energy meter; the dynamic error measuring device for the energy meter includes a small signal generation unit, a test signal power amplification unit, a measurement unit, and a calculation and control unit; wherein, The small signal generation unit is used to generate Uu small analog signal and Ui small analog signal according to the control of the calculation control unit, and output the Uu small analog signal and Ui small analog signal to the test signal power amplification unit; The test signal power amplification unit is used to amplify the Uu small analog signal to obtain a voltage test signal, amplify the Ui small analog signal to obtain a current test signal, and output the voltage test signal and the current test signal to the measurement unit. The measurement unit is used to determine the electrical energy value based on the received voltage test signal and the current test signal, and output the electrical energy value to the calculation and control unit; It also includes: a calibration unit, which comprises a calibration signal power amplification module and a current summing module; wherein, The small signal generation unit is also used to generate a Ux small analog signal according to the control of the calculation control unit, and output the Ux small analog signal to the calibration signal power amplification module; The calibration signal power amplification module is used to amplify the Ux small analog signal to obtain a current calibration signal, and output the current calibration signal to the current summing module; The measurement unit is also used to output the received current test signal to the current summing module; The current summing module is used to determine the merged current signal based on the received current calibration signal and the current test signal; The meter under test is used to receive the voltage test signal and the current test signal output by the dynamic error measurement device of the electricity meter, and to determine the value of the electrical energy to be tested based on the voltage test signal and the current test signal. The calculation and control unit is further configured to determine the dynamic error of the meter under test based on the energy value to be tested and the energy value. In the hardware architecture of the energy meter dynamic error measurement device, the calibration unit is an independent component.

8. A method for testing dynamic error in an energy meter dynamic error measurement system, characterized in that, The method, implemented by the dynamic error measurement system for electricity meters according to claim 7, comprises: The Uu and Ui small analog signals are generated according to the control of the calculation and control unit. The Uu small analog signal and the Ui small analog signal are output to the test signal power amplification unit, so that the test signal power amplification unit amplifies the Uu small analog signal to obtain a voltage test signal and amplifies the Ui small analog signal to obtain a current test signal. The voltage test signal and the current test signal are output to the measurement unit so that the measurement unit determines the electrical energy value based on the voltage test signal and the current test signal; The voltage test signal and the current test signal are output to the meter under test so that the meter under test can determine the energy value to be tested based on the voltage test signal and the current test signal. The dynamic error of the meter under test is determined based on the electrical energy value and the electrical energy value to be tested.

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