A kind of electric energy metering device wiring correct determination detector

Abstract

The application provides an electric energy metering device wiring correct judgment detector, comprising a signal source module, a detection module, a micro control unit (MCU), a display module, a power module and a correction sensor. The signal source module generates analog voltage and current signals in the case that the electric energy metering device is not electrified, simulating the operation state of the power grid. The detection module is connected to the voltage and current input end of the electric energy metering device, the MCU controls the signal source module and collects the response signal, and judges the wiring correctness after analysis and processing. The correction sensor provides a current direction reference signal. The detector can detect the wiring in the case that the electric energy metering device is not electrified or is electrified, improving the detection accuracy and work efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of electric energy metering, and in particular to a detector for determining the correctness of wiring of an electric energy metering device. Background Art

[0002] Electricity metering is mainly used for trade settlement of electricity commodities and assessment of internal economic and technical indicators of enterprises. Its accuracy is directly related to the economic interests of power generation enterprises, power supply enterprises and electricity users. The installation of electricity metering devices, as an important part of metering work, is an important link in the production and operation management of power enterprises and the safe operation of power grids. Its technology, skill level and management level are not only related to the development of the power industry and the image of power enterprises, but also affect the fairness, justice, accuracy and reliability of electricity trade settlement. Due to differences in work skills and business levels or negligence of on-site staff, the secondary metering line of the electricity meter may be connected incorrectly, the polarity may be reversed or the phase may be broken, which will not only bring economic losses, but also easily cause personal safety risks.

[0003] At present, the following two methods are mainly used to check the installation of electric energy metering:

[0004] The first method is to use instruments for testing, such as volt-ampere phase meters, energy meter field calibrators, and energy metering fault error detectors. These testing methods assume that power is already supplied to the site and there is a certain load. They also require high technical skills from the installer and are relatively complex to operate. Therefore, most on-site installers do not use instruments for measurement. The second method is to use a multimeter (or a light) for wiring. This can determine the continuity of the wires, but it cannot determine the polarity. This is time-consuming and labor-intensive, and there is a risk of secondary wiring errors, which requires a high level of technical skills from the installer.

[0005] Because wiring errors in energy metering devices can occur in hundreds of thousands of ways, wiring errors are prone to errors. Both of the above methods have significant limitations. First, they require relatively high skills and pose certain safety risks. Second, they are complex and time-consuming. Third, due to technical reasons, a comprehensive inspection is impossible. For example, it is impossible to determine the polarity of transformers and distinguish the input and output wires of current circuits. Therefore, wiring tests cannot be performed with a meter without power or load. Fourth, because the wiring test terminals of energy metering devices carry strong electricity, the risk is increased and can easily lead to personal safety issues. Summary of the Invention

[0006] The purpose of the present invention is to provide a detection instrument for determining the correctness of wiring of an electric energy metering device, so as to improve the accuracy and work efficiency of equipment detection and wiring verification by on-site personnel.

[0007] To achieve the above-mentioned object, the present invention provides a detection instrument for determining the correctness of wiring of an electric energy metering device, comprising: a signal source module, a detection module, an MCU, a display module, a power supply module and a calibration sensor;

[0008] The signal source module is used to generate analog voltage signals and analog current signals when the electric energy metering device is not powered, so as to simulate the operating state of the actual power grid so as to detect the electric energy metering device;

[0009] The detection module includes a voltage connection terminal and a current connection terminal, the voltage connection terminal is used to connect to the voltage input terminal of the electric energy metering device, and the current connection terminal is used to connect to the current input terminal of the electric energy metering device;

[0010] The MCU is used to control the signal source module to generate an analog voltage signal and an analog current signal when the electric energy metering device is not powered, and connect the analog voltage signal and the analog current signal to the electric energy metering device through the voltage connection terminal and the current connection terminal, and collect the voltage signal and the current signal responded by the electric energy metering device through the detection module, and analyze and process the voltage signal and the current signal to determine whether the wiring of the electric energy metering device is correct;

[0011] The MCU is further configured to, when the electric energy metering device is energized, directly connect the analog voltage signal and the analog current signal to the electric energy metering device through the voltage connection terminal and the current connection terminal, collect the voltage signal and the current signal of the electric energy metering device through the detection module, and perform analysis and processing based on the voltage signal and the current signal to determine whether the wiring of the electric energy metering device is correct;

[0012] The power supply module is used to convert the external power supply into the operating voltage required by each module inside the detector;

[0013] The correction sensor is used to provide a current direction reference signal for analysis and processing of the MCU.

[0014] Preferably, the voltage connection terminals include A-phase voltage connection terminals, B-phase voltage connection terminals, C-phase voltage connection terminals and N-phase voltage connection terminals, and the current connection terminals include A-phase current connection terminals, B-phase current connection terminals and C-phase current connection terminals, and each phase current connection terminal includes a positive connection terminal and a negative connection terminal.

[0015] Preferably, the MCU is specifically used to compare the analog voltage signal and analog current signal generated by the signal source module with the voltage signal and current signal responded by the electric energy metering device when the electric energy metering device is not powered, and determine the on / off, phase, phase sequence and current direction of the electric energy metering device based on the comparison result.

[0016] Preferably, the MCU is specifically used to determine that there is a disconnection in any phase voltage circuit if the voltage value of any phase voltage signal of the detected energy metering device is close to zero or below a preset threshold when the energy metering device is energized; and to determine that there is a disconnection in any phase current circuit if the current value of any phase current signal is close to zero or below a preset threshold.

[0017] Preferably, the MCU is specifically used to obtain waveform data of the three-phase voltage signal or the waveform data of the three-phase current signal when the electric energy metering device is energized, analyze the phase difference of the three-phase voltage signal or the three-phase current signal according to the waveform data, and determine whether there is a phase error and phase sequence error according to the phase difference.

[0018] Preferably, the MCU is specifically used to obtain the current direction of the current signal when the electric energy metering device is energized. If the measured current direction is consistent with the current direction reference signal of the calibration sensor, the current wiring is correct; if not, the current wiring is incorrect.

[0019] The electric energy metering device wiring correctness determination detector proposed by the present invention has the following beneficial effects:

[0020] The present invention can determine whether the wiring is correct when the electric energy metering device is not energized, thereby improving the safety of on-site detection; by simulating the actual operating state of the power grid, it can accurately detect the wiring condition of the electric energy metering device, thereby improving the accuracy of detection; the present invention has a live detection function, adapts to different working environments, and improves the adaptability of detection; the equipment has high integration and is easy to operate, which helps to improve the work efficiency of on-site personnel; the use of a correction sensor further improves the accuracy of analysis and avoids misjudgment due to incorrect current direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, other drawings obtained based on these drawings still fall within the scope of the present invention.

[0022] Figure 1 The present invention is a circuit diagram of an electric energy metering device wiring correctness determination detector according to an embodiment of the present invention.

[0023] Figure 2 The figure is a schematic diagram of the appearance of a detection instrument for determining the correctness of wiring of an electric energy metering device according to an embodiment of the present invention.

[0024] Markings in the figure:

[0025] 1-Function selection key, 2-Start button, 3-Confirm button, 4-Display unit, 5-Connector, 6-Signal wire terminal block, 7-Shielded cable, 8-Current sensor, 9-Signal lead, 10-Connection head. DETAILED DESCRIPTION

[0026] The detailed description of the accompanying drawings is intended to serve as an illustration of the current embodiment of the present application and is not intended to represent the only form in which the present application can be implemented. It should be understood that the same or equivalent functions can be accomplished by different embodiments intended to be included in the spirit and scope of the present application.

[0027] See Figure 1 , an embodiment of the present invention provides a detection instrument for determining the correctness of wiring of an electric energy metering device, comprising: a signal source module, a detection module, an MCU, a display module, a power supply module and a calibration sensor;

[0028] The signal source module is used to generate analog voltage signals and analog current signals when the electric energy metering device is not powered, so as to simulate the operating state of the actual power grid so as to detect the electric energy metering device;

[0029] The detection module includes a voltage connection terminal and a current connection terminal, the voltage connection terminal is used to connect to the voltage input terminal of the electric energy metering device, and the current connection terminal is used to connect to the current input terminal of the electric energy metering device;

[0030] The MCU is used to control the signal source module to generate an analog voltage signal and an analog current signal when the electric energy metering device is not powered, and connect the analog voltage signal and the analog current signal to the electric energy metering device through the voltage connection terminal and the current connection terminal, and collect the voltage signal and the current signal responded by the electric energy metering device through the detection module, and analyze and process the voltage signal and the current signal to determine whether the wiring of the electric energy metering device is correct;

[0031] The MCU is further configured to, when the electric energy metering device is energized, directly connect the analog voltage signal and the analog current signal to the electric energy metering device through the voltage connection terminal and the current connection terminal, collect the voltage signal and the current signal of the electric energy metering device through the detection module, and perform analysis and processing based on the voltage signal and the current signal to determine whether the wiring of the electric energy metering device is correct;

[0032] The power supply module is used to convert the external power supply into the operating voltage required by each module inside the detector;

[0033] The correction sensor is used to provide a current direction reference signal for analysis and processing of the MCU.

[0034] Specifically, when the electric energy metering device is de-energized, the signal source module is activated to generate analog voltage and current signals. These analog signals are designed based on the actual operating state of the power grid and can simulate changes in voltage and current in the grid, thereby providing the electric energy metering device with test conditions similar to the actual operating environment. When the analog voltage and current signals generated by the signal source module are connected to the electric energy metering device through the voltage and current connection terminals of the detection module, the detection module can collect the electric energy metering device's response to the analog voltage and current signals.

[0035] The working principle of MCU (micro control unit) is as follows:

[0036] De-energized detection: The MCU controls the signal source module to generate analog signals and connects these signals to the electric energy metering device through the connection terminals of the detection module. Then, the MCU collects the voltage and current signals responded by the electric energy metering device and analyzes and processes them. By comparing the analog signals with the response signals, the MCU can determine whether the wiring of the electric energy metering device is correct.

[0037] Live detection: When the energy metering device is energized, the MCU can directly collect the voltage and current signals of the energy metering device through the connection terminals of the detection module. Similarly, the MCU analyzes and processes these signals to determine whether the wiring is correct.

[0038] The MCU's analysis and processing includes logical judgment of the wiring method, comparison of signal phases, current direction, etc., to determine the correctness of the wiring.

[0039] The calibration sensor provides a reference signal of the current direction to the MCU. When analyzing and processing the current signal, the MCU will refer to the signal of the calibration sensor to ensure that the judgment of the current direction is accurate.

[0040] In summary, the embodiment of the present invention simulates the grid signal and collects the response signal of the electric energy metering device, combines it with the reference signal of the calibration sensor, and performs analysis and processing by the MCU, so as to accurately determine whether the wiring of the electric energy metering device is correct, and can perform effective detection regardless of whether it is energized or not.

[0041] Furthermore, the voltage connection terminal includes an A-phase voltage connection terminal, a B-phase voltage connection terminal, a C-phase voltage connection terminal and an N-phase voltage connection terminal, and the current connection terminal includes an A-phase current connection terminal, a B-phase current connection terminal and a C-phase current connection terminal, and each phase current connection terminal includes a positive connection terminal and a negative connection terminal.

[0042] Specifically, if Figure 2As shown, the A-phase, B-phase, and C-phase voltage connection terminals are used to connect to the three-phase voltage inputs of the electric energy metering device. In a three-phase AC system, phases A, B, and C are voltage sources spaced 120 degrees apart and represent different phases of the three-phase power supply. The N-phase voltage connection terminal is used to connect to the neutral line (also known as the zero line). In a three-phase, four-wire system with a grounded neutral point, the N-phase voltage connection terminal provides a voltage reference to ground.

[0043] The A-phase, B-phase, and C-phase current connection terminals are used to connect to the three-phase current input terminals of the electric energy metering device. These terminals correspond to the voltage terminals and are used to measure the current flowing through each phase. Each phase current connection terminal includes positive and negative terminals to distinguish the direction of the current. Knowing the direction of the current flow is crucial for current measurement, as it affects energy measurement and the correctness of the wiring. The design of these terminals enables the tester to adapt to three-phase four-wire or three-phase three-wire electric energy metering devices. In a three-phase system, correctly distinguishing and connecting the voltage and current of each phase is crucial, as incorrect wiring can lead to inaccurate energy measurement and even damage the equipment.

[0044] like Figure 2 As shown, pressing the Start button 2 automatically triggers a test according to the selected function. The Confirm button 3 allows you to select whether to perform live testing. Connector 5 connects to a shielded cable 7, allowing you to begin plugging and unplugging. The shielded cable 7 transmits current and reduces interference. The signal line terminal block 6 allows for quick plug-in connection. A high-precision clamp-on current sensor 8 is used for current acquisition and current correction, ensuring more accurate measurements. Signal lead 9 transmits current or voltage. A banana connector 10, used in conjunction with a clip, connects to the terminals of an energy metering device.

[0045] Furthermore, the MCU is specifically used to compare the analog voltage signal and analog current signal generated by the signal source module with the voltage signal and current signal responded by the electric energy metering device when the electric energy metering device is not powered, and determine the on / off state, phase, phase sequence and current direction of the electric energy metering device based on the comparison result.

[0046] Specifically, the analog voltage and current signals generated by the signal source module are pre-set to simulate the voltage and current waveforms under normal grid conditions. The analog voltage signal is input to the corresponding voltage input terminals of the electric energy metering device through the A-phase, B-phase, and C-phase voltage connection terminals. The analog current signal is input to the corresponding current input terminals of the electric energy metering device through the positive and negative poles of the A-phase, B-phase, and C-phase current connection terminals. After receiving the analog signal, the electric energy metering device will generate corresponding voltage and current response signals. The detection module collects these response signals and transmits the data to the MCU for processing. The comparative analysis is as follows:

[0047] On / off judgment: The MCU compares the input analog signal with the collected response signal to see if they exist. If the response signal exists, it means the circuit is on; if the response signal does not exist, it means the circuit is off.

[0048] Phase determination: The MCU analyzes whether the phase of the response signal is consistent with the phase of the input analog signal. If they are consistent, the phase is correct; if they are inconsistent, there is a phase error;

[0049] Phase sequence determination: The MCU checks whether the phase sequence of the A, B, and C three-phase response signals is consistent with the phase sequence of the input analog signal. In a three-phase system, the correctness of the phase sequence is crucial to the accuracy of energy measurement.

[0050] Current direction determination: The MCU uses the reference signal provided by the calibration sensor to determine whether the response signals of the positive and negative poles of the current connection terminals conform to the expected current direction. If the current direction is opposite to the expected direction, it indicates that there is an error in the wiring.

[0051] Determination result output: Based on the results of the above comparison and analysis, the MCU outputs the determination result through the display module to inform the operator whether the wiring of the energy metering device is correct and the specific problem (such as on / off, phase, phase sequence or current direction error).

[0052] Through this comparison and judgment process, the MCU can effectively detect the wiring status of the energy metering device, ensuring that all wiring is correct before actual power-on operation, thereby improving the accuracy of energy metering and the safety of the system.

[0053] Furthermore, the MCU is specifically used to determine that there is a disconnection in the voltage circuit of any phase if the voltage value of any phase voltage signal of the detected energy metering device is close to zero or below a preset threshold when the energy metering device is energized; and to determine that there is a disconnection in the current circuit of any phase if the current value of any phase current signal is close to zero or below a preset threshold.

[0054] Specifically, when the energy metering device is energized, the MCU (microcontroller unit) detects and determines whether the voltage and current circuits are disconnected through the following steps:

[0055] Collecting live signals: When the electric energy metering device is in a live state, the MCU controls the detection module to collect the voltage and current signals of the electric energy metering device in real time. The collected signals include the voltage signals of phase A, phase B, and phase C and the corresponding current signals.

[0056] Voltage signal analysis: The MCU analyzes each phase voltage signal it collects and checks its voltage value. If the voltage value of any phase voltage signal is close to zero or lower than a preset threshold (this threshold is set based on the voltage range during normal circuit operation), the MCU will make the following judgments:

[0057] Disconnection judgment: If the voltage value is too low, it indicates that the phase voltage circuit is disconnected, because under normal working conditions, the voltage of each phase should be maintained in a relatively stable range.

[0058] Current signal analysis: At the same time, the MCU also analyzes the collected current signals of each phase and checks its current value. If the current value of any phase current signal is close to zero or lower than a preset threshold (this threshold is set according to the current range when the circuit is operating normally), the MCU will make the following judgments:

[0059] Disconnection judgment: If the current value is too low, it indicates that the phase current circuit is disconnected. Because under normal working conditions, the current of each phase should be maintained in a relatively stable range. Even under light load conditions, the current value will not be close to zero.

[0060] Result output: Based on the above analysis, the MCU outputs the judgment result through the display module to inform the operator which phase voltage or current circuit is disconnected.

[0061] Through this detection method, the MCU can effectively detect the wiring status of the energy metering device even when it is powered, ensure the normal operation of the energy metering device, and promptly discover potential wiring problems, thereby improving the reliability and safety of the system.

[0062] Furthermore, the MCU is specifically used to obtain waveform data of the three-phase voltage signal or the three-phase current signal when the electric energy metering device is energized, analyze the phase difference of the three-phase voltage signal or the three-phase current signal according to the waveform data, and determine whether there is a phase error and phase sequence error according to the phase difference.

[0063] Specifically, when the energy metering device is energized, the MCU (microcontroller unit) analyzes the phase difference of the three-phase voltage signal or the three-phase current signal through the following steps to determine whether there is a phase error and a phase sequence error:

[0064] Waveform data acquisition: The MCU controls the detection module to collect waveform data of three-phase voltage signals and / or three-phase current signals in real time under power conditions. The waveform data contains detailed information about the voltage or current changes over time, which is crucial for analyzing phase relationships.

[0065] Waveform Data Analysis: The MCU processes the collected waveform data and calculates the phase difference between the three-phase voltage or current signals. Phase difference refers to the time delay or lead between the three-phase signals. In an ideal three-phase AC system, the phase difference between the three-phase voltage or current should be 120 degrees.

[0066] Phase difference calculation: By analyzing the peaks or zero crossings of the waveform data, the MCU can determine the phase position of each phase voltage or current. Phase difference calculation typically involves comparing the time delays between the three phase signals. For example, if Phase A leads Phase B, and Phase B leads Phase C, and each phase difference is approximately 120 degrees, the phase sequence is correct.

[0067] Phase error determination: If the calculated phase difference is not equal to 120 degrees, or the phase relationship does not conform to the order of phase A leading phase B, and phase B leading phase C, the MCU will determine that a phase error exists. The phase error may be caused by a wiring error or an internal problem in the energy metering device.

[0068] Phase sequence error determination: If the phase relationship of the three-phase signal does not conform to the correct phase sequence (for example, phase A leads phase C, and phase C leads phase B), the MCU will determine that there is a phase sequence error. Phase sequence error is usually caused by incorrect phase connection during wiring.

[0069] Result output: Based on the analysis results of the phase difference, the MCU outputs the judgment results of whether there is a phase error and phase sequence error through the display module.

[0070] By using this method of analyzing phase difference, the MCU can accurately detect the phase and phase sequence of the electric energy metering device in the energized state, thereby improving the detection efficiency and accuracy of the wiring of the electric energy metering device.

[0071] Furthermore, the MCU is specifically used to obtain the current direction of the current signal when the electric energy metering device is energized. If the measured current direction is consistent with the current direction reference signal of the calibration sensor, the current wiring is correct; if not, the current wiring is incorrect.

[0072] Specifically, when the energy metering device is energized, the MCU (microcontroller unit) obtains the current direction of the current signal and determines whether the current wiring is correct through the following steps:

[0073] Current direction reference signal acquisition: The calibration sensor provides a known current direction reference signal. This reference signal represents the correct current direction and is usually achieved through a current sensor with a known direction.

[0074] Current signal acquisition: The MCU controls the detection module to collect current signals in the energized state in real time. These signals are input to the detection module through the current connection terminals (including the positive and negative connection terminals of phases A, B, and C).

[0075] Current direction analysis: The MCU analyzes the collected current signal to determine its direction. This usually involves detecting the zero crossing point of the current signal and determining whether the current is flowing from the positive electrode to the negative electrode or vice versa.

[0076] Current direction comparison: The MCU compares the measured current direction with the current direction reference signal provided by the calibration sensor. If the measured current direction is consistent with the reference signal, it means that the current wiring is correct, that is, the positive and negative poles of the current are consistent with the direction defined by the reference signal. If the measured current direction is inconsistent with the reference signal, it means that there is an error in the current wiring, possibly with the positive and negative poles connected incorrectly.

[0077] Result output: Based on the comparison results of the current direction, the MCU outputs whether the current wiring is correct or not through the display module. If the current wiring is incorrect, the MCU can also provide specific error information, such as which phase of the current wiring is incorrect, so that the operator can quickly locate and correct the problem.

[0078] This detection method allows the MCU to accurately determine the correctness of the current wiring while energized, which is crucial for ensuring accurate energy metering and safe system operation. The use of a calibration sensor improves detection reliability and avoids misjudgments due to incorrect current direction.

[0079] The above disclosure is merely a preferred embodiment of the present invention and certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A detector for determining the correctness of wiring of an electric energy metering device, characterized in that: include: Signal source module, detection module, MCU, display module, power module and calibration sensor; The signal source module is used to generate analog voltage signals and analog current signals when the electric energy metering device is not powered, so as to simulate the operating state of the actual power grid so as to detect the electric energy metering device; The detection module includes a voltage connection terminal and a current connection terminal, the voltage connection terminal is used to connect to the voltage input terminal of the electric energy metering device, and the current connection terminal is used to connect to the current input terminal of the electric energy metering device; The MCU is used to control the signal source module to generate an analog voltage signal and an analog current signal when the electric energy metering device is not powered, and connect the analog voltage signal and the analog current signal to the electric energy metering device through the voltage connection terminal and the current connection terminal, and collect the voltage signal and the current signal responded by the electric energy metering device through the detection module, and analyze and process the voltage signal and the current signal to determine whether the wiring of the electric energy metering device is correct; The MCU is further configured to, when the electric energy metering device is energized, directly connect the analog voltage signal and the analog current signal to the electric energy metering device through the voltage connection terminal and the current connection terminal, collect the voltage signal and the current signal of the electric energy metering device through the detection module, and perform analysis and processing based on the voltage signal and the current signal to determine whether the wiring of the electric energy metering device is correct; The power supply module is used to convert the external power supply into the operating voltage required by each module inside the detector; The correction sensor is used to provide a current direction reference signal for analysis and processing of the MCU.

2. The detector according to claim 1, characterized in that The voltage connection terminals include an A-phase voltage connection terminal, a B-phase voltage connection terminal, a C-phase voltage connection terminal, and an N-phase voltage connection terminal; the current connection terminals include an A-phase current connection terminal, a B-phase current connection terminal, and a C-phase current connection terminal; and each phase current connection terminal includes a positive connection terminal and a negative connection terminal.

3. The detector according to claim 2, characterized in that The MCU is specifically used to compare the analog voltage signal and analog current signal generated by the signal source module with the voltage signal and current signal responded by the electric energy metering device when the electric energy metering device is not powered, and determine the on / off, phase, phase sequence and current direction of the electric energy metering device based on the comparison result.

4. The detector according to claim 2, characterized in that The MCU is specifically configured to determine, when the electric energy metering device is energized, if the voltage value of any phase voltage signal of the electric energy metering device detected is close to zero or below a preset threshold, whether the phase voltage circuit is disconnected; If the current value of any phase current signal is close to zero or lower than a preset threshold, it is determined that the current line of any phase is disconnected.

5. The detector according to claim 4, characterized in that: The MCU is specifically used to obtain waveform data of a three-phase voltage signal or a three-phase current signal when the electric energy metering device is energized, analyze the phase difference of the three-phase voltage signal or the three-phase current signal based on the waveform data, and determine whether there is a phase error and a phase sequence error based on the phase difference.

6. The detector according to claim 4, characterized in that: The MCU is specifically used to obtain the current direction of the current signal when the electric energy metering device is energized. If the measured current direction is consistent with the current direction reference signal of the calibration sensor, the current wiring is correct; if not, the current wiring is incorrect.

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