Gauge position monitoring circuit of virtual meter in electric energy meter detection device

Abstract

The utility model discloses a meter position monitoring circuit of virtual meters in an electric energy meter detection device in the field of electric power industry testing, which comprises a power source, a standard meter, a plurality of entity meters and virtual meters with the same number as the entity meters, and the power source, the plurality of entity meters and the standard meter are electrically connected. The virtual meter comprises a voltage isolation monitoring module, a parameter display module, a temperature detection module and an alarm indication module. According to the utility model, the virtual meter simulates the metering function of the entity meter, outputs the electric energy pulse to calculate the electric energy error, performs year-on-year error calculation on the electric energy pulse output by the entity meter by an error plate in the detection device, and prevents the false detection meter from flowing into the hand of a user; the power consumption of the entity table is detected through the virtual table, even if the electric energy metering error is qualified, the entity table can be judged as a problem table, the situation that the false detection table flows into a user is avoided, the safety of the detection device and the working continuity of the detection device are improved, and the efficiency is also improved.

Description

Technical Field

[0001] This utility model relates to the field of power industry testing, specifically to a meter position monitoring circuit in an energy meter testing device using a virtual meter. Background Technology

[0002] The rapid development of the power industry has led to a surge in the application of electronic smart meters. Therefore, ensuring qualified electronic smart meters reach the market and are used by users is a pressing issue. Electronic smart meters need to be tested before they enter the warehouse; they also need to be tested after exceeding their storage period before reaching users; and they need to be tested after being removed from users and returned to the warehouse. All these testing stages require meter testing devices, which can be either platform-based or line-based. Previously, without virtual meter testing devices, safety was unreliable. For example, short circuits in the voltage terminals could cause large currents, burning or igniting the related connecting wires at the meter location; the testing process was not continuous; for example, if a meter malfunctioned, testing could only continue after the fault was rectified, interrupting the testing and wasting time; meters with power error values ​​close to the threshold might have potential problems, but without data for comparison, falsely detected meters could reach users; and meters with excessive power consumption but acceptable error values ​​were also considered problematic meters but still reached users.

[0003] However, although the existing circuit incorporates a virtual meter detection device with short-circuit monitoring for meter column voltage, if a short circuit occurs, it will detect a surge in current on the voltage line, thus instantly isolating the meter position. Otherwise, a short circuit could easily cause related connecting wires to burn or even char, leading to unpredictable losses.

[0004] Furthermore, the addition of a virtual meter detection device can monitor the temperature of the current column at the meter position. If the temperature exceeds a threshold, the meter position can be bypassed. This allows the current to flow away from the meter position bypass relay, bypassing the meter position altogether, thus stopping current flow through the current column. During meter testing, for example, poor contact between the current column and the meter base can increase internal resistance. When testing the Imax100A current term, the high current can cause the current column to heat up, leading to excessively high temperatures. If the meter position is not bypassed, this could cause the meter base to burn or deform, thereby damaging the electricity meter.

[0005] Therefore, those skilled in the art have provided a meter position monitoring circuit for a virtual meter in an energy meter detection device to solve the problems mentioned in the background art. Utility Model Content

[0006] The purpose of this invention is to provide a meter position monitoring circuit for a virtual meter in an energy meter testing device, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] The virtual meter in the meter position monitoring circuit of the electricity meter testing device includes a power source, a standard meter, several physical meters, and an equal number of virtual meters. The power source, several physical meters, and the standard meter are electrically connected. The virtual meter includes a voltage isolation monitoring module, a parameter display module, a temperature detection module, and an alarm indication module. One interface of each alarm indication module in each virtual meter is connected to the standard meter, and another interface of each alarm indication module in each virtual meter is connected to the 485 communication module. The voltage isolation monitoring modules in the virtual meters are connected to the power source and the standard meter. The parameter display module in the virtual meter is connected to the voltage line sampling voltage module and then to the physical meter. The temperature detection module in the virtual meter is connected to the current bypass monitoring module and then to the physical meter and the sampling voltage module on the current line. The sampling voltage module on the current line is connected in parallel with the physical meter and is also connected to the virtual meter. The virtual meter is also connected to a voltage line sampling current module and a current line sampling current module.

[0009] As a further embodiment of this utility model: the voltage sampling module on the voltage line includes resistors R102, R5, R1, R2, R3 and R4 connected in series with the voltage phase line SC1. Resistor R4 is connected to the second interface of transformer T3. The first interface of transformer T3 is connected to the voltage phase line SC2. The third interface of transformer T3 is connected to resistors R15, R14 and C3 in parallel and then connected to resistor R18. Diodes D5 and D7 and operational amplifier U1A are connected in parallel between the fourth interface and the third interface of transformer T3. The eighth interface of operational amplifier U1A is connected to capacitor C6 and then grounded. The fourth interface of operational amplifier U1A is connected to capacitor C5 and then grounded.

[0010] As a further embodiment of this utility model: the voltage line sampling current module includes a transformer T1. Capacitors D1 and D3 are connected in parallel between the first and second interfaces of transformer T1. A capacitor C1, a resistor R9, and a resistor R8 are connected in parallel to the second interface of capacitor D1 and the first interface of capacitor D3, and then a resistor R12 is connected. The sixth interface of operational amplifier U1B is also connected to the second interface of capacitor D1 and the first interface of capacitor D3. The seventh interface of operational amplifier U1B is connected to resistor R12. The fifth interface of operational amplifier U1B is connected to resistor R105 and then connected to the first interface of capacitor D1 and the second interface of capacitor D3. The fifth interface of operational amplifier U1B is grounded.

[0011] As a further embodiment of this utility model: the voltage sampling module on the current line includes voltage phase line SC3 and voltage phase line SC4. The voltage phase line SC3 is connected in series with resistors R6 and R7 and then connected to the second interface of transformer T4. The first interface of transformer T4 is connected to voltage phase line SC4. The third interface of transformer T4 is connected to resistors R16, R17 and C4 in parallel and then connected to resistor R19. The fourth interface of transformer T4 is connected in parallel with the third interface with diodes D6 and D8 and operational amplifier U2A. The eighth interface of operational amplifier U2A is connected to capacitor C8 and then grounded. The fourth interface of operational amplifier U2A is connected to capacitor C7 and then grounded.

[0012] As a further embodiment of this utility model: the current sampling module on the current line includes a transformer T2. Capacitors D2 and D4 are connected in parallel between the first and second interfaces of transformer T2. A capacitor C2, a resistor R10, and a resistor R11 are connected in parallel to the second interface of capacitor D2 and the first interface of capacitor D4, and then connected to the second interfaces of transistors Q3 and Q4. The second interface of capacitor D2 and the first interface of capacitor D4 are also connected to the sixth interface of operational amplifier U2B. The seventh interface of operational amplifier U2B is connected to the second interface of transistors Q3 and Q4 after a resistor R13 is connected. The fifth interface of operational amplifier U2B is connected to the first interface of capacitor D2 and the second interface of capacitor D4 after a resistor R108 is connected. The fifth interface of operational amplifier U2B is grounded. The seventh interface of operational amplifier U2B is also connected to the first interface of transistors Q3 and Q4.

[0013] As a further embodiment of this utility model: the voltage isolation monitoring module includes a transformer T1. The first interface of transformer T1 is connected to the changeover switch PL1A and then to terminal UA. The second interface of transformer T1 is connected to terminal UA. A resistor R7 is connected in parallel between the fourth and third interfaces of transformer T1. A resistor R4 is also connected to the third interface of transformer T1. A diode Z01 and the third interface of an operational amplifier are connected to resistor R4. The first and second interfaces of the operational amplifier are connected. Operational amplifier U1A is connected to capacitor C1 and then grounded. The first interface of operational amplifier U1A is connected to R5 and then to the fifth interface of operational amplifier U1B, capacitor C3, and resistor R. The circuit consists of 9 parallel resistors, with R9 grounded. The seventh interface of operational amplifier U1B is connected to diode D1 and then returns to the sixth interface of operational amplifier U1B. Diode D1 is connected to resistor R8. Resistor R8 is connected to the parallel circuit of resistor R10 and capacitor C2 and then grounded. Resistor R8 is also connected to the fifth interface of operational amplifier U2B. The sixth interface of operational amplifier U2B is connected to resistor R2 and then grounded. The sixth interface of operational amplifier U2B is connected to resistor R7 and then grounded. The seventh interface of operational amplifier U2B is connected to resistor R6 and diode D2. Diode D2 is connected to diode Z02 and then grounded. Diode D2 is connected to resistor R3 and LED1 and then grounded.

[0014] As a further embodiment of this utility model: the current bypass monitoring module includes a transformer T1. A resistor R7 is connected between the first and second interfaces of the transformer T1. A resistor R2 and a diode ZD1 are also connected to the first interface of the transformer T1 and then grounded. The third interface of an operational amplifier U1A is also connected to the first interface of the transformer T1. The second interface of the operational amplifier U1A is connected to the first interface. The operational amplifier U1A is connected to a capacitor C1 and then grounded. A resistor R3 is also connected to the first interface of the operational amplifier U1A. A parallel circuit of a capacitor C2 and a resistor R9 is connected to the resistor R3 and then grounded. It is also connected to the fifth interface of operational amplifier U1B. The seventh interface of operational amplifier U1B is connected to diode D1 and then to its sixth interface. Resistor R4 is connected to diode D1. Resistor R4 is connected to ground after being connected to a parallel circuit of resistor R8 and capacitor C3. Resistor R4 is also connected to the third interface of operational amplifier U2A. The second interface of operational amplifier U2A is connected to resistor R1 and resistor R10. The first interface of operational amplifier U2A is connected in series with resistor R5, diode D2 and diode ZD2 and then grounded together with resistor R10. Resistor R2 and light-emitting diode LED1 are also connected to diode D2 and then grounded.

[0015] As a further embodiment of this utility model: the temperature monitoring module includes a chip U3, a resistor R41 is connected to the fourth interface of the chip U3, a temperature sensor J12 is connected to the third interface and the second interface of the chip U3, a resistor R19 and a resistor R21 are connected in series to the third interface of the chip U3 and then connected to the first interface of the chip U3, and a temperature sensor J15 is connected to the first interface and the second interface of the chip U3.

[0016] This invention simulates the metering function of a physical meter using a virtual meter, outputting electrical energy pulses to calculate electrical energy error. The error is compared with the electrical energy pulses output by the physical meter via an error board in the detection device, preventing falsely detected meters from reaching users. Furthermore, by using the virtual meter to detect the power consumption of the physical meter itself, even if the electrical energy metering error is within acceptable limits, it will be identified as a faulty meter, further preventing falsely detected meters from reaching users. This improves the safety and continuity of the detection device, thus increasing its efficiency. Attached Figure Description

[0017] Figure 1 This is a comprehensive diagram illustrating the application of the virtual table in the monitoring device according to this utility model;

[0018] Figure 2 This is a circuit diagram of the voltage sampling module on the voltage line in this utility model;

[0019] Figure 3 This is a circuit diagram of the voltage line sampling current module in this utility model;

[0020] Figure 4 This is a circuit diagram of the current sampling module on the current line in this utility model;

[0021] Figure 5 This is a circuit diagram of the voltage sampling module on the current line in this utility model;

[0022] Figure 6 This is a circuit diagram of the voltage isolation monitoring module in this utility model;

[0023] Figure 7 This is a circuit diagram of the current bypass monitoring module in this utility model;

[0024] Figure 8 This is a circuit diagram of the current bypass monitoring module in this utility model. Detailed Implementation

[0025] Please see Figures 1-8The virtual meter in the meter position monitoring circuit of the electricity meter detection device includes a power source, a standard meter, several physical meters, and an equal number of virtual meters. The power source, several physical meters, and the standard meter are electrically connected. The virtual meter includes a voltage isolation monitoring module, a parameter display module, a temperature detection module, and an alarm indication module. One interface of each alarm indication module in each virtual meter is connected to the standard meter, and the other interface of each alarm indication module in each virtual meter is connected to the 485 communication module. The voltage isolation monitoring modules in the virtual meters are connected to the power source and the standard meter. The parameter display module in the virtual meter is connected to the voltage line sampling voltage module and then to the physical meter. The temperature detection module in the virtual meter is connected to the current bypass monitoring module and then to the physical meter and the sampling voltage module on the current line. The sampling voltage module on the current line is connected in parallel with the physical meter and is also connected to the virtual meter. The virtual meter is also connected to a voltage line sampling current module and a current line sampling current module.

[0026] By adopting the above technical solution, the metering monitoring and false alarm prevention functions are achieved through two main signal sampling modules: voltage line and current line. The voltage and current on both lines are measured, along with their phase angles. This data is displayed and, through the measured parameters, simulates the energy metering function of the physical meter, calculating power and energy. The energy is then converted into energy pulse output (simulating the energy metering pulse output of the physical meter), which is captured and compared with the standard energy pulse output from a standard meter to calculate the energy error. The energy error value is provided to the host computer via RS-485 communication, facilitating comparison and analysis with the energy error data from the error board. The error value is calculated by the error board capturing the energy output pulses from the physical meter and the standard energy pulses from the standard meter. Simultaneously, based on the relevant parameters measured on the voltage and current lines, the power consumption of the physical meter itself can be calculated and provided to the host computer. The metering accuracy is determined by comparing the power consumption and error.

[0027] The voltage sampling module on the voltage line includes resistors R102, R5, R1, R2, R3, and R4 connected in series with the voltage phase line SC1. Resistor R4 is connected to the second interface of transformer T3. The first interface of transformer T3 is connected to the voltage phase line SC2. The third interface of transformer T3 is connected to resistors R15, R14, and C3 in parallel, and then connected to resistor R18. Diodes D5 and D7 and operational amplifier U1A are connected in parallel between the fourth interface and the third interface of transformer T3. The eighth interface of operational amplifier U1A is connected to capacitor C6 and then grounded. The fourth interface of operational amplifier U1A is connected to capacitor C5 and then grounded.

[0028] The voltage line sampling current module includes a transformer T1. Capacitors D1 and D3 are connected in parallel between the first and second interfaces of transformer T1. Capacitor C1, resistor R9, and resistor R8 are connected in parallel to the second interface of capacitor D1 and the first interface of capacitor D3, and then connected to resistor R12. The second interface of capacitor D1 and the first interface of capacitor D3 are also connected to the sixth interface of operational amplifier U1B. The seventh interface of operational amplifier U1B is connected to resistor R12. The fifth interface of operational amplifier U1B is connected to resistor R105 and then connected to the first interface of capacitor D1 and the second interface of capacitor D3. The fifth interface of operational amplifier U1B is grounded.

[0029] The voltage sampling module on the current line includes voltage phase lines SC3 and SC4. Voltage phase line SC3 is connected in series with resistors R6 and R7 and then connected to the second interface of transformer T4. The first interface of transformer T4 is connected to voltage phase line SC4. The third interface of transformer T4 is connected to resistors R16, R17 and C4 in parallel and then connected to resistor R19. Diodes D6 and D8 and operational amplifier U2A are connected in parallel between the fourth interface and the third interface of transformer T4. The eighth interface of operational amplifier U2A is connected to capacitor C8 and then grounded. The fourth interface of operational amplifier U2A is connected to capacitor C7 and then grounded.

[0030] The current sampling module on the current line includes a transformer T2. Capacitors D2 and D4 are connected in parallel between the first and second interfaces of transformer T2. The second interface of capacitor D2 and the first interface of capacitor D4 are connected in parallel with capacitor C2, resistor R10, and resistor R11, and then connected to the second interfaces of transistors Q3 and Q4. The second interface of capacitor D2 and the first interface of capacitor D4 are also connected to the sixth interface of operational amplifier U2B. The seventh interface of operational amplifier U2B is connected to resistor R13 and then connected to the second interfaces of transistors Q3 and Q4. The fifth interface of operational amplifier U2B is connected to resistor R108 and then connected to the first interface of capacitor D2 and the second interface of capacitor D4. The fifth interface of operational amplifier U2B is grounded. The seventh interface of operational amplifier U2B is also connected to the first interface of transistors Q3 and Q4.

[0031] The voltage isolation monitoring module includes a transformer T1. The first interface of transformer T1 is connected to the changeover switch PL1A and then to terminal UA. The second interface of transformer T1 is also connected to terminal UA. A resistor R7 is connected in parallel between the fourth and third interfaces of transformer T1. A resistor R4 is also connected to the third interface of transformer T1. A diode Z01 and the third interface of an operational amplifier are connected to resistor R4. The first and second interfaces of the operational amplifier are connected. Operational amplifier U1A is connected to capacitor C1 and then grounded. The first interface of operational amplifier U1A is connected to R5 and then to the fifth interface of operational amplifier U1B and the parallel connection of capacitor C3 and resistor R9. The circuit is connected with R9 grounded. The seventh interface of operational amplifier U1B is connected to diode D1 and then returns to the sixth interface of operational amplifier U1B. Diode D1 is connected to resistor R8. Resistor R8 is connected to the parallel circuit of resistor R10 and capacitor C2 and then grounded. Resistor R8 is also connected to the fifth interface of operational amplifier U2B. The sixth interface of operational amplifier U2B is connected to resistor R2 and then grounded. The sixth interface of operational amplifier U2B is connected to resistor R7 and then grounded. The seventh interface of operational amplifier U2B is connected to resistor R6 and diode D2. Diode D2 is connected to diode Z02 and then grounded. Diode D2 is connected to resistor R3 and LED1 and then grounded.

[0032] The current bypass monitoring module includes a transformer T1. A resistor R7 is connected between the first and second interfaces of transformer T1. A resistor R2 and a diode ZD1 are also connected to the first interface of transformer T1 before being grounded. The third interface of operational amplifier U1A is also connected to the first interface of operational amplifier U1A. The second interface of operational amplifier U1A is connected to the first interface. Operational amplifier U1A is connected to capacitor C1 before being grounded. A resistor R3 is also connected to the first interface of operational amplifier U1A. A parallel circuit of capacitor C2 and resistor R9 is connected to resistor R3 before being grounded. A current bypass monitoring module is also connected to resistor R3. The fifth and seventh interfaces of operational amplifier U1B are connected to diode D1 and then to its sixth interface. Resistor R4 is connected to diode D1. Resistor R4 is connected to ground after being connected to a parallel circuit of resistor R8 and capacitor C3. Resistor R4 is also connected to the third interface of operational amplifier U2A. The second interface of operational amplifier U2A is connected to resistor R1 and resistor R10. The first interface of operational amplifier U2A is connected in series with resistor R5, diode D2, and diode ZD2, and then grounded together with resistor R10. Resistor R2 and LED1 are also connected to diode D2 and then grounded.

[0033] The temperature monitoring module includes a chip U3. A resistor R41 is connected to the fourth interface of the chip U3. A temperature sensor J12 is connected to the third and second interfaces of the chip U3. A resistor R19 and a resistor R21 are connected in series to the third interface of the chip U3 and then connected to the first interface of the chip U3. A temperature sensor J15 is connected to the first and second interfaces of the chip U3.

[0034] By adopting the above technical solution, when the voltage isolation monitoring module is normal, the voltage phase line from the power source, such as UA (the same applies to other UB and UC), flows from... Figure 6 The voltage from the UA terminal passes through the normally closed contact of the relay, then through the current transformer, back to the terminal, and then applies voltage to the meter position. In the event of a short circuit, the current surges, and the control CPU samples the current signal through the current transformer, thereby disconnecting the relay and isolating the meter position.

[0035] When no physical meter is connected to the current bypass monitoring module, the line current will pass through... Figure 7 The bridge rectifier freewheeling (adding a through-hole current transformer to the bridge rectifier current line) controls the CPU to sample the current signal through the current transformer. When the current exceeds the threshold value, the current bypass relay can be controlled to bypass the meter position, so that the current will not be unable to form a loop due to a meter not being hung at a certain position, thus affecting the meter detection of other positions.

[0036] Thirdly, temperature sensors J12 and J15 detect the temperature of the current column at the meter position. When the current column of the meter position is not in close and reliable contact with the meter base, its internal resistance increases. When detecting a large current of Imax100A, the temperature will surge, potentially causing the meter base wiring holes to burn or deform, damaging the meter. When the control CPU detects that the current column temperature exceeds the threshold, it will bypass the meter position, preventing current from flowing through the current terminal of the meter position, avoiding accidents, allowing the meter testing process to continue, and not affecting the testing of other meter positions.

[0037] The above events can all be detected by the meter position alarm, clearly indicating the faulty meter position. If the fault can be easily and quickly resolved, the operator can resolve the fault. If it cannot be resolved, the meter position can be isolated during the current meter inspection and bypassed. The meter position can be ignored during the next meter inspection, without affecting the continuity of the entire testing device's operation, thereby improving work efficiency.

[0038] The working principle of this invention is as follows: It has two main signal sampling modules, one for voltage lines and one for current lines. The voltage and current on the voltage lines and the other for current lines are measured separately, along with their phase angles. These parameters are displayed, and the measured parameters also simulate the energy metering function of a physical meter, calculating power and energy. The energy is finally converted into energy pulse output (simulating the energy metering pulse output of a physical meter), which is captured by the meter itself and compared with the standard energy pulse output from a standard meter to calculate the energy error. The energy error value is provided to the host computer via RS-485 communication, facilitating comparison and analysis with the energy error data from the error board. The error value of the error board is calculated by capturing the energy output pulses from the physical meter and the standard energy pulses from the standard meter. Simultaneously, based on the relevant parameters measured on the voltage and current lines, the power consumption of the physical meter itself can be calculated and provided to the host computer. The meter's accuracy is determined by comparing the power consumption and error.

[0039] The voltages on the voltage lines are UA, UB, and UC, and the currents on the voltage lines are UL_Ia, UL_Ib, and UL_Ic. The phase angles of the voltages and currents on the voltage lines are ΦUL_a, ΦUL_b, and ΦUL_c.

[0040] The voltages on the current lines are IL_Ua, IL_Ub, and IL_Uc, and the currents on the current lines are IA, IB, and IC. The phase angles of the voltages and currents on the current lines are ΦIL_a, ΦIL_b, and ΦIL_c.

[0041] The phase angles between UA, UB, UC and IA, IB, IC are named ΦUA, ΦUB, ΦUC, ΦIA, ΦIB, and ΦIC.

[0042] The power consumption of the physical meter can then be calculated based on the above measurement parameters.

[0043] The active power consumption on the voltage line is represented by UL_PA, UL_PB, and UL_PC, respectively. Then UL_PA = UA * UL_Ia * cosΦUL_a; UL_PB = UB * UL_Ib * cosΦUL_b; UL_PC = UC * UL_Ic * cosΦUL_c.

[0044] The apparent power dissipation on the voltage line is represented by UL_SA, UL_SB, and UL_SC, respectively. Then, UL_SA = UA * UL_Ia; UL_SB = UB * UL_Ib; UL_SC = UC * UL_Ic.

[0045] The active power consumption on the current line is represented by IL_PA, IL_PB, and IL_PC. Then IL_PA = IL_Ua * IA * ΦIL_a; IL_PB = IL_Ub * IB * ΦIL_b; IL_PC = IL_Uc * IC * ΦIL_c.

[0046] The apparent power dissipation on the current line is represented by IL_SA, IL_SB, and IL_SC. Then IL_SA = IL_Ua * IA; IL_SB = IL_Ub * IB; IL_SC = IL_Uc * IC.

[0047] The above describes the power consumption monitoring of the physical table by the virtual table. This power consumption is the physical table's own power consumption. The calculated power consumption value can be uploaded to the host computer via RS-485 communication for analysis. If the power error calculation of the system error board is qualified and meets the verification requirements, but the power consumption of the physical table exceeds the standard, the table will still be judged as a problematic table, thus preventing false detections.

[0048] Samples were taken for UA, UB, UC, IA, IB, IC, and ΦUA, ΦUB, ΦUC, ΦIA, ΦIB, ΦIC. These samples can then be used to simulate a physical meter to calculate active power, reactive power, and active and reactive energy. This power and energy represent the metering function of the analog meter. Three-phase active and reactive power are represented by PA, PB, PC, QA, QB, and QC. Therefore: PA = UA * IA * cosΦIA, PB = UB * IB * cosΦIB, PC = UC * IC * cosΦIC. QA = UA * IA * sinΦIA, QB = UB * IB * sinΦIB, QC = UC * IC * sinΦIC. Total active power P = PA + PB + PC; total reactive power Q = QA + QB + QC. We typically calculate active and reactive energy by sampling every four cycles and then converting the energy into pulse outputs. We capture this power pulse using the virtual meter's CPU timer, and simultaneously capture the standard power pulse output from the standard meter, as well as the pulse constant transmitted from the host computer, to calculate the power error. Finally, this error value is uploaded to the host computer via RS-485 communication for analysis. If the error calculated by the error board is close to the threshold, while the error calculated by the virtual meter is far below the threshold, the meter may also have a problem or potential issues. The operator can retest the meter or add / expand the detection items, such as adding a 0.01Ib current error detection item. This prevents false alarms and ensures that faulty or potentially problematic meters do not reach users.

[0049] These are the four main monitoring functions of virtual meters in electricity meter testing devices. By analyzing data from both physical and virtual meters, false detections by physical meters can be eliminated.

[0050] Therefore, this virtual meter is used to monitor each physical meter location in the electricity meter monitoring device. Since physical meters are either single-phase or three-phase, there are corresponding single-phase and three-phase virtual meters. The virtual meter has four main monitoring functions.

[0051] Firstly, the meter's position safety is monitored. When a short circuit occurs at the voltage terminal of the meter, an alarm will be triggered and the position will be isolated. When an open circuit occurs at the current terminal, an alarm will be triggered and the position will be bypassed. When the current terminal temperature is too high, an alarm will be triggered and the position will be bypassed.

[0052] Secondly, it can improve the efficiency of the testing device. The testing task of the device is heavy and the volume is large. The number of meters to be tested in a day is often planned. Failure to complete the task will delay the work and cause a chain reaction. Therefore, when a meter has an alarm event, the current test can be automatically isolated or bypassed. When installing meters next time, the alarm meters can be ignored according to the event, so as not to interrupt the testing process, thereby improving efficiency.

[0053] Third, it can simulate the metering function of a physical meter, synchronously measuring electrical energy and ultimately outputting an electrical energy pulse. This pulse is captured by the device itself and compared with the standard electrical energy pulse output from a captured standard meter to calculate the electrical energy error. The error result is uploaded to a host computer for comparison and analysis with the error board in the retrieved detection device, preventing false detection meters from reaching users.

[0054] Fourth, power consumption detection of the physical meter itself. The detection value is provided to the host computer to monitor the power consumption of the physical meter itself, which can also prevent false meter readings from reaching the user.

[0055] By utilizing the four main monitoring functions of the virtual meter, the safety and efficiency of the monitoring device can be improved, and false alarms can be prevented from reaching users.

[0056] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A meter position monitoring circuit in an electricity meter testing device, comprising a power source, a standard meter, several physical meters, and a number of virtual meters equal to the number of physical meters, characterized in that: The power source, several physical meters, and a standard meter are electrically connected. The virtual meter includes a voltage isolation monitoring module, a parameter display module, a temperature detection module, and an alarm indication module. One interface of each alarm indication module in each virtual meter is connected to the standard meter, and the other interface of each alarm indication module in each virtual meter is connected to the 485 communication module. The voltage isolation monitoring modules in the virtual meters are connected to the power source and the standard meter. The parameter display module in the virtual meter is connected to the voltage line sampling voltage module and then to the physical meter. The temperature detection module in the virtual meter is connected to the current bypass monitoring module and then to the physical meter and the sampling voltage module on the current line. The sampling voltage module on the current line is connected in parallel with the physical meter and is also connected to the virtual meter. The virtual meter is also connected to a voltage line sampling current module and a current line sampling current module.

2. The meter position monitoring circuit in the energy meter detection device according to claim 1, characterized in that: The voltage sampling module on the voltage line includes resistors R102, R5, R1, R2, R3, and R4 connected in series with the voltage phase line SC1. Resistor R4 is connected to the second interface of transformer T3. The first interface of transformer T3 is connected to the voltage phase line SC2. The third interface of transformer T3 is connected to resistors R15, R14, and C3 in parallel, and then connected to resistor R18. Diodes D5 and D7 and operational amplifier U1A are connected in parallel between the fourth interface and the third interface of transformer T3. The eighth interface of operational amplifier U1A is connected to capacitor C6 and then grounded. The fourth interface of operational amplifier U1A is connected to capacitor C5 and then grounded.

3. The meter position monitoring circuit in the energy meter detection device according to claim 1, characterized in that: The voltage line sampling current module includes a transformer T1. Capacitors D1 and D3 are connected in parallel between the first and second interfaces of transformer T1. Capacitors C1, R9, and R8 are connected in parallel to the second interface of capacitor D1 and the first interface of capacitor D3, and then connected to resistor R12. The sixth interface of operational amplifier U1B is also connected to the second interface of capacitor D1 and the first interface of capacitor D3. The seventh interface of operational amplifier U1B is connected to resistor R12. The fifth interface of operational amplifier U1B is connected to resistor R105 and then connected to the first interface of capacitor D1 and the second interface of capacitor D3. The fifth interface of operational amplifier U1B is grounded.

4. The meter position monitoring circuit in the energy meter detection device according to claim 1, characterized in that: The voltage sampling module on the current line includes voltage phase lines SC3 and SC4. Voltage phase line SC3 is connected in series with resistors R6 and R7 and then connected to the second interface of transformer T4. The first interface of transformer T4 is connected to voltage phase line SC4. The third interface of transformer T4 is connected to resistors R16, R17 and C4 in parallel and then connected to resistor R19. Diodes D6 and D8 and operational amplifier U2A are connected in parallel between the fourth interface and the third interface of transformer T4. The eighth interface of operational amplifier U2A is connected to capacitor C8 and then grounded. The fourth interface of operational amplifier U2A is connected to capacitor C7 and then grounded.

5. The meter position monitoring circuit in the energy meter detection device according to claim 1, characterized in that: The current sampling module on the current line includes a transformer T2. Capacitors D2 and D4 are connected in parallel between the first and second interfaces of transformer T2. A capacitor C2, a resistor R10, and a resistor R11 are connected in parallel to the second interface of capacitor D2 and the first interface of capacitor D4, and then connected to the second interfaces of transistors Q3 and Q4. The second interface of capacitor D2 and the first interface of capacitor D4 are also connected to the sixth interface of operational amplifier U2B. The seventh interface of operational amplifier U2B is connected to the second interface of transistors Q3 and Q4 after a resistor R13 is connected. The fifth interface of operational amplifier U2B is connected to the first interface of capacitor D2 and the second interface of capacitor D4 after a resistor R108 is connected. The fifth interface of operational amplifier U2B is grounded. The seventh interface of operational amplifier U2B is also connected to the first interface of transistors Q3 and Q4.

6. The meter position monitoring circuit in the energy meter detection device according to claim 1, characterized in that: The voltage isolation monitoring module includes a transformer T1. The first interface of transformer T1 is connected to a changeover switch PL1A and then to terminal UA. The second interface of transformer T1 is also connected to terminal UA. A resistor R7 is connected in parallel between the fourth and third interfaces of transformer T1. A resistor R4 is also connected to the third interface of transformer T1. A diode Z01 and the third interface of an operational amplifier are connected to resistor R4. The first and second interfaces of the operational amplifier are connected. Operational amplifier U1A is connected to capacitor C1 and then grounded. The first interface of operational amplifier U1A is connected to resistor R5 and then to the fifth interface of operational amplifier U1B and the parallel circuit of capacitor C3 and resistor R9. Furthermore, R9 is grounded. The seventh interface of operational amplifier U1B is connected to diode D1 and then flows back to the sixth interface of operational amplifier U1B. Diode D1 is connected to resistor R8. Resistor R8 is connected to the parallel circuit of resistor R10 and capacitor C2 and then grounded. Resistor R8 is also connected to the fifth interface of operational amplifier U2B. The sixth interface of operational amplifier U2B is connected to resistor R2 and then grounded. The sixth interface of operational amplifier U2B is connected to resistor R7 and then grounded. The seventh interface of operational amplifier U2B is connected to resistor R6 and diode D2. Diode D2 is connected to diode Z02 and then grounded. Diode D2 is connected to resistor R3 and LED1 and then grounded.

7. The meter position monitoring circuit in the energy meter detection device according to claim 1, characterized in that: The current bypass monitoring module includes a transformer T1. A resistor R7 is connected between the first and second interfaces of transformer T1. A resistor R2 and a diode ZD1 are also connected to the first interface of transformer T1 and then grounded. The third interface of operational amplifier U1A is also connected to the first interface of operational amplifier U1A. The second interface of operational amplifier U1A is connected to the first interface. Operational amplifier U1A is connected to capacitor C1 and then grounded. A resistor R3 is also connected to the first interface of operational amplifier U1A. A parallel circuit of capacitor C2 and resistor R9 is connected to resistor R3 and then grounded. An operational amplifier is also connected to resistor R3. The fifth and seventh interfaces of amplifier U1B are connected to diode D1 and then to its sixth interface. Resistor R4 is connected to diode D1. Resistor R4 is connected to ground after being connected to a parallel circuit of resistor R8 and capacitor C3. Resistor R4 is also connected to the third interface of operational amplifier U2A. The second interface of operational amplifier U2A is connected to resistor R1 and resistor R10. The first interface of operational amplifier U2A is connected in series with resistor R5, diode D2, and diode ZD2, and then grounded together with resistor R10. Resistor R2 and LED1 are also connected to diode D2 and then grounded.

8. The meter position monitoring circuit in the energy meter detection device according to claim 1, characterized in that: The temperature detection module includes a chip U3. A resistor R41 is connected to the fourth interface of the chip U3. A temperature sensor J12 is connected to the third and second interfaces of the chip U3. A resistor R19 and a resistor R21 are connected in series to the third interface of the chip U3 and then connected to the first interface of the chip U3. A temperature sensor J15 is connected to the first and second interfaces of the chip U3.

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