Voltage reference chip automatic monitoring system and method applied to electric energy meter

Abstract

The invention discloses a voltage reference chip automatic monitoring system applied to an electric energy meter. The voltage reference chip automatic monitoring system comprises an upper computer, a test tool and a digital multimeter, the upper computer is respectively connected with the test tool and the digital multimeter, and the test tool is connected with the multimeter; the test tool comprises a voltage reference module, a power supply module, a dot matrix liquid crystal module, a control module and a communication module. The control module is respectively connected with the dot matrix liquid crystal module, the communication module and the voltage reference module, the power supply module is respectively connected with the voltage reference module, the dot matrix liquid crystal module, the control module and the communication module, and the power supply module is used for providing a power supply for the test tool. The invention further discloses a voltage reference chip automatic monitoring method applied to the electric energy meter. The technical problems of how to monitor and record the voltage values of the voltage reference chip at different temperatures in real time and how to provide a basis for high and low temperature precision research of an electric energy meter are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric energy meters, and in particular to an automatic monitoring system and method for a voltage reference chip applied to an electric energy meter. Background Art

[0002] The key characteristics of voltage reference chips include high stability, high precision, low temperature coefficient, low noise, and low drift, making them crucial in high-end electricity meters. For high-end electricity meters, their accuracy at high and low temperatures is closely related to the temperature coefficient characteristics of the voltage reference chip. High-end electricity meters consist of three components: a metering unit, a power supply unit, and a control unit. The metering unit is the core module of high-end electricity meters. To achieve Class D or higher sampling accuracy, high-end electricity meters must utilize discrete voltage reference chips to ensure the high precision, reliability, and stability of the sampling unit. To further study the temperature coefficient of voltage reference chips at high and low temperatures and evaluate the high and low temperature characteristics of voltage reference chips from different manufacturers, it is imperative to develop an automated monitoring system and method for voltage reference chips in electricity meters. This system addresses the technical challenge of real-time monitoring and recording of the voltage values of the voltage reference chip at different temperatures, providing a foundation for research into the high and low temperature accuracy of electricity meters. Summary of the Invention

[0003] The main purpose of the present invention is to propose an automatic monitoring system and method for a voltage reference chip used in an electric energy meter, aiming to solve the technical problem of how to monitor and record the voltage value of the voltage reference chip at different temperatures in real time, and provide a basis for the high and low temperature accuracy research of the electric energy meter.

[0004] To achieve the above-mentioned object, the present invention provides an automatic monitoring system for a voltage reference chip applied to an electric energy meter, wherein the automatic monitoring system for a voltage reference chip applied to an electric energy meter comprises:

[0005] A host computer, a test fixture, and a digital multimeter; the host computer is connected to the test fixture and the digital multimeter respectively, and the test fixture is connected to the multimeter;

[0006] The test tooling includes a voltage reference module, a power module, a dot matrix liquid crystal module, a control module and a communication module; the control module is respectively connected to the dot matrix liquid crystal module, the communication module and the voltage reference module, and the power module is respectively connected to the voltage reference module, the dot matrix liquid crystal module, the control module and the communication module, and the power module is used to provide power for the test tooling.

[0007] In one of the preferred solutions, the voltage reference module includes an analog switch selection circuit and several voltage reference chip peripheral circuits, and the analog switch selection circuit is connected to the voltage reference chip peripheral circuit and the control module respectively.

[0008] In one of the preferred solutions, the voltage reference chip peripheral circuit includes 16 SOP-8 test sockets.

[0009] In one of the preferred embodiments, the voltage reference chip peripheral circuit includes a voltage reference chip U1; pin 2 of the voltage reference chip U1 is respectively connected to capacitor C1 and capacitor C2, pin 5 of the voltage reference chip U1 is connected to capacitor C3, pin 6 of the voltage reference chip U1 is respectively connected to capacitor C4, capacitor C5, capacitor C13 and resistor R1, and pin 4 of the voltage reference chip U1, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C13 and the other end of resistor R1 are grounded.

[0010] In one of the preferred solutions, the dot matrix liquid crystal module realizes data exchange with the control module via SPI communication.

[0011] In one of the preferred solutions, the host computer is connected to the test fixture via RS485 communication.

[0012] In one preferred solution, the digital multimeter is a 6.5-digit high-precision digital multimeter.

[0013] In one of the preferred solutions, the tester is installed in a temperature box or a heat flow hood.

[0014] In one of the preferred solutions, the digital multimeter is connected to the host computer via a network port.

[0015] A method for automatically monitoring a voltage reference chip for an electric energy meter includes the following steps:

[0016] S1. Click the Start Test button and set the test flag to change the button to Stop Test.

[0017] S2. Connect the digital multimeter via Ethernet and configure the sampling range to 6-digit decimal sampling mode;

[0018] S3. Select the voltage reference chip to be tested, send the number of the corresponding voltage reference chip to the test tool through the interface, and adjust the corresponding channel of the corresponding voltage reference chip;

[0019] S4. After waiting for the test fixture to return the switching completion instruction, read the sampling value of the digital multimeter through Ethernet and record it;

[0020] S5. Determine whether the stop test button is pressed. If so, set the test flag to change the button to start testing and stop communicating with the test fixture and the digital multimeter. Otherwise, return to step S3.

[0021] In the above technical solution of the present invention, the voltage reference chip automatic monitoring system applied to the electric energy meter includes: a host computer, a test fixture and a digital multimeter; the host computer is connected to the test fixture and the digital multimeter respectively, and the test fixture is connected to the multimeter; the test fixture includes a voltage reference module, a power module, a dot matrix liquid crystal module, a control module and a communication module; the control module is connected to the dot matrix liquid crystal module, the communication module and the voltage reference module respectively, and the power module is connected to the voltage reference module, the dot matrix liquid crystal module, the control module and the communication module respectively, and the power module is used to provide power to the test fixture. The present invention can simultaneously monitor the voltage values of multiple reference chips in high and low temperature environments through the digital multimeter and the host computer, and can select the reference chip of the corresponding channel by switching the analog switch, and verify the temperature characteristics of multiple chips at the same time, solving the technical problem of how to monitor and record the voltage values of the voltage reference chip at different temperatures in real time, providing a basis for the high and low temperature accuracy research of the electric energy meter. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] 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, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0023] Figure 1 This is a schematic diagram of an automatic monitoring system for a voltage reference chip applied to an electric energy meter according to an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of a test tool according to an embodiment of the present invention;

[0025] Figure 3 A schematic diagram of an analog switch selection circuit according to an embodiment of the present invention;

[0026] Figure 4 Schematic diagram of the peripheral circuit of the voltage reference chip according to an embodiment of the present invention;

[0027] Figure 5 is a schematic diagram of a dot matrix liquid crystal module according to an embodiment of the present invention;

[0028] Figure 6 is a schematic diagram of a control module according to an embodiment of the present invention;

[0029] Figure 7 A schematic diagram of an automatic monitoring method for a voltage reference chip of an electric energy meter according to an embodiment of the present invention;

[0030] Figure 8This is a temperature-voltage curve diagram of the host computer voltage benchmark test in an embodiment of the present invention.

[0031] The realization of the objectives, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0033] Moreover, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] See also Figures 1-6 According to one aspect of the present invention, the present invention provides an automatic monitoring system for a voltage reference chip applied to an electric energy meter, wherein the automatic monitoring system for a voltage reference chip applied to an electric energy meter comprises:

[0035] A host computer, a test fixture, and a digital multimeter; the host computer is connected to the test fixture and the digital multimeter respectively, and the test fixture is connected to the multimeter;

[0036] The test tooling includes a voltage reference module, a power module, a dot matrix liquid crystal module, a control module and a communication module; the control module is respectively connected to the dot matrix liquid crystal module, the communication module and the voltage reference module, and the power module is respectively connected to the voltage reference module, the dot matrix liquid crystal module, the control module and the communication module, and the power module is used to provide power for the test tooling.

[0037] Specifically, in this embodiment, the test fixture can be used to simultaneously collect voltage data of 16 voltage reference chips at different ambient temperatures, which is convenient for verifying the high and low temperature characteristics and hysteresis characteristics of voltage reference chips of different manufacturers and models; the host computer sends a channel selection command to the test fixture through RS485 communication, and the aerial module of the test fixture selects the voltage reference chip of the corresponding channel after receiving the command. At the same time, the control module collects the ambient temperature through the internal sensor and sends it back to the host computer through RS485 communication. The digital multimeter collects the voltage signal of the voltage reference chip of the corresponding channel and uploads it to the host computer through the network port. The host computer saves the collected voltage signal to the document.

[0038] Specifically, in this embodiment, the test tool is placed in a temperature box or a heat flow hood, and different ambient temperatures can be set through the temperature box. Every 10 seconds, the host computer automatically sends a channel selection command, and the digital multimeter collects the corresponding voltage information into a document, and finally obtains a curve of the reference voltage changing with temperature, thereby providing a basis for the high and low temperature characteristic analysis of the voltage reference chip, and the high voltage value of each channel and the temperature value of the current voltage reference chip can be displayed through the dot matrix liquid crystal module of the test tool.

[0039] Specifically, in this embodiment, the voltage reference module includes an analog switch selection circuit and several voltage reference chip peripheral circuits, and the analog switch selection circuit is connected to the voltage reference chip peripheral circuit and the control module respectively; wherein, the voltage reference chip peripheral circuit includes 16 SOP-8 test sockets, and voltage reference chips from different manufacturers can be placed in the SOP-8 test sockets, which has the characteristics of flexible disassembly and assembly, and the voltage reference chip is powered by 5V DC, outputting 2.5V high-precision reference voltage, each channel has independent output, and each channel is equipped with a test socket, which can adapt to voltage reference chips of different packages, and does not limit the output voltage value of the reference, and has extremely strong compatibility; the analog switch selection circuit is connected to the control module, and can select the corresponding voltage reference chip according to the instructions issued by the control module, and finally upload the voltage value of the corresponding voltage reference chip to the host computer.

[0040] Specifically, in this embodiment, the voltage reference chip peripheral circuit includes a voltage reference chip U1; pin 2 of the voltage reference chip U1 is respectively connected to capacitor C1 and capacitor C2, pin 5 of the voltage reference chip U1 is connected to capacitor C3, pin 6 of the voltage reference chip U1 is respectively connected to capacitor C4, capacitor C5, capacitor C13 and resistor R1, and pin 4 of the voltage reference chip U1, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C13 and the other end of resistor R1 are grounded; the present invention is provided with 16 groups of voltage reference chip peripheral circuits, which are not specifically limited in the present invention and can be set according to needs.

[0041] Specifically, in this embodiment, the analog switch selection circuit includes an analog switch chip U11, pin 1 of the analog switch chip U11 is respectively connected to the resistor R13 and the control module, the other end of the resistor R13 is connected to the power supply end, pin 16 of the analog switch chip U11 is respectively connected to the power supply end and the capacitor C32, pins 8 and 15 of the analog switch chip U11 and the other end of the capacitor C32 are grounded, and pins 2, 3, 4, 5, 6, 7, 9, 10, 11, 12, 13, and 14 of the analog switch chip are connected to the peripheral circuit of the voltage reference chip; in the present invention, multiple analog switch selection circuits can be set, which is not specifically limited in the present invention and can be set according to needs.

[0042] Specifically, in this embodiment, one end of the power module is connected to 220V AC power, and the other end is isolated to output a 5V voltage, which is powered by a low-voltage difference linear regulator. The low-voltage difference linear regulator has the characteristics of good stability and high precision, and provides a stable power supply for the voltage reference chip.

[0043] Specifically, in this embodiment, the dot matrix liquid crystal module realizes data interaction with the control module through SPI communication. The test tool has a display function, and the currently recorded chip channel height and the voltage value and temperature value corresponding to the voltage reference chip can be viewed in real time on the liquid crystal display screen; the dot matrix liquid crystal module includes a display screen P1, and the 1, 2, 3, and 4 pins of the display screen P1 are connected to the control module, the 5 pin of the display screen P1 is respectively connected to the resistor R191 and the capacitor C46, and the 6 pins of the display screen P1 are respectively connected to the resistor R19 Pin 0 of the display screen P1 is connected to a capacitor C48, pin 7 of the display screen P1 is connected to a resistor R189 and a capacitor C62, pin 8 of the display screen P1 is connected to a resistor R188 and a capacitor C45, pin 9 of the display screen P1 is connected to a resistor R187 and a capacitor C43, the other ends of the capacitors C43, C45, C46, C48 and C62 are grounded, and the other ends of the resistors R187, R188, R189, R190 and R191 are connected to a control module.

[0044] Specifically, in this embodiment, the host computer is connected to the test fixture via RS485 communication.

[0045] Specifically, in this embodiment, the digital multimeter adopts a 6.5-digit high-precision digital multimeter; the digital multimeter is connected to the host computer through a network port; in the present invention, the digital multimeter adopts a 6.5-digit high-precision digital multimeter with model FLUKE8845A, which is not specifically limited in the present invention and can be set according to needs. The digital multimeter has a 6.5-digit digital resolution and a Vdc accuracy of up to 0.0024%. The 6.5-digit digital multimeter has high accuracy, multiple functions, and is convenient to use. It can measure frequency and period. The built-in screen display function can display the benchmark data transmitted by the test tool in real time, making it convenient to read high-precision voltage values, so that under normal temperature conditions, the basic error of 1 is improved from 0.02% to 0.01%.

[0046] Specifically, in this embodiment, the communication module is connected to the control module using RS485 communication mode, the host sends a control command to the control module, the control module receives the command to select the sampling channel, and the voltage reference chip of the corresponding channel of the digital multimeter performs analog sampling; an external 220V AC input is used to power the entire test fixture. The control module serves as the core module of the test fixture to control and communicate with each module, communicates with the dot matrix liquid crystal module through the SPI interface, communicates and exchanges data with the host computer through the RS485 interface, controls the analog switch selection circuit through the I / O port, selects the voltage reference chip of the corresponding channel, and transmits the voltage data to the six-and-a-half-digit digital multimeter.

[0047] See also Figure 7 According to another aspect of the present invention, the present invention provides an automatic monitoring method for a voltage reference chip applied to an electric energy meter, wherein the automatic monitoring method for a voltage reference chip applied to an electric energy meter comprises the following steps:

[0048] S1. Click the Start Test button and set the test flag to change the button to Stop Test.

[0049] S2. Connect the digital multimeter via Ethernet and configure the sampling range to 6-digit decimal sampling mode;

[0050] S3. Select the voltage reference chip to be tested, send the number of the corresponding voltage reference chip to the test tool through the interface, and adjust the corresponding channel of the corresponding voltage reference chip;

[0051] S4. After waiting for the test fixture to return the switching completion instruction, read the sampling value of the digital multimeter through Ethernet and record it;

[0052] S5. Determine whether the stop test button is pressed. If so, set the test flag to change the button to start testing and stop communicating with the test fixture and the digital multimeter. Otherwise, return to step S3.

[0053] Specifically, in this embodiment, in order to collect the voltage values of 16 voltage reference chips in real time, the host computer communicates with the test fixture through the RS485 interface, and uploads the voltage values collected in real time by the digital multimeter to the host computer. The host computer can control the start and stop of the test fixture, and can choose to read the voltage value of the corresponding voltage reference chip all the time, and export the real-time collected data through an Excel file; see Figure 8, the reference voltage value of each voltage reference chip is read in real time by the host computer, and the temperature-voltage curve is drawn. The temperature characteristics of the voltage reference chip can be read intuitively, and multiple chips can be selected at the same time. The differences between each chip can be read intuitively from the curve chart, and the high and low temperature characteristics of the voltage reference chips of each manufacturer can be compared to provide a basis for the selection of the reference chip; the high and low temperature characteristics of the voltage reference chips of different manufacturers vary greatly, and different chips of the same manufacturer also have great differences. The chips with low temperature drift coefficients can be screened out through the automatic monitoring device, and used for high-end electricity meters with extremely strict high and low temperature accuracy requirements, thereby improving the accuracy of high-end electricity meters under high and low temperature conditions.

[0054] The above are only preferred embodiments of the present invention and are not intended to limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present description and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. An automatic monitoring system for voltage reference chips used in electric energy meters, characterized in that: include: Host computer, test fixture and digital multimeter; The host computer is connected to the test fixture and the digital multimeter respectively, and the test fixture is connected to the multimeter; The test fixture includes a voltage reference module, a power module, a dot matrix liquid crystal module, a control module and a communication module; The control module is connected to the dot matrix liquid crystal module, the communication module and the voltage reference module respectively; the power module is connected to the voltage reference module, the dot matrix liquid crystal module, the control module and the communication module respectively; and the power module is used to provide power for the test tooling.

2. The automatic monitoring system for voltage reference chip used in electric energy meter according to claim 1, characterized in that: The voltage reference module includes an analog switch selection circuit and a plurality of voltage reference chip peripheral circuits. The analog switch selection circuit is connected to the voltage reference chip peripheral circuit and the control module respectively.

3. The automatic monitoring system for voltage reference chip used in electric energy meter according to claim 2, characterized in that: The peripheral circuit of the voltage reference chip includes 16 sop-8 test sockets.

4. The automatic monitoring system for voltage reference chip used in electric energy meter according to claim 2, characterized in that: The voltage reference chip peripheral circuit includes a voltage reference chip U1; pin 2 of the voltage reference chip U1 is respectively connected to capacitor C1 and capacitor C2, pin 5 of the voltage reference chip U1 is connected to capacitor C3, pin 6 of the voltage reference chip U1 is respectively connected to capacitor C4, capacitor C5, capacitor C13 and resistor R1, and the other ends of pin 4 of the voltage reference chip U1, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C13 and resistor R1 are grounded.

5. The automatic monitoring system for voltage reference chip used in electric energy meter according to any one of claims 1 to 4, characterized in that: The dot matrix liquid crystal module realizes data interaction with the control module through the SPI communication mode.

6. The automatic monitoring system for voltage reference chip used in electric energy meter according to any one of claims 1 to 4, characterized in that: The host computer is connected to the test fixture via RS485 communication.

7. The automatic monitoring system for voltage reference chip used in electric energy meter according to any one of claims 1 to 4, characterized in that: The digital multimeter is a 6.5-digit high-precision digital multimeter.

8. The automatic monitoring system for voltage reference chip used in electric energy meter according to any one of claims 1 to 4, characterized in that: The tester is placed in a temperature chamber or a heat hood.

9. The automatic monitoring system for voltage reference chip used in electric energy meter according to any one of claims 1 to 4, characterized in that: The digital multimeter is connected to the host computer via an Internet port.

10. A method comprising the automatic monitoring system for a voltage reference chip applied to an electric energy meter according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Click the Start Test button and set the test flag to change the button to Stop Test. S2. Connect the digital multimeter via Ethernet and configure the sampling range to 6-digit decimal sampling mode; S3. Select the voltage reference chip to be tested, send the number of the corresponding voltage reference chip to the test tool through the interface, and adjust the corresponding channel of the corresponding voltage reference chip; S4. After waiting for the test fixture to return the switching completion instruction, read the sampling value of the digital multimeter through Ethernet and record it; S5. Determine whether the stop test button is pressed. If so, set the test flag to change the button to start testing and stop communicating with the test fixture and the digital multimeter. Otherwise, return to step S3.

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