CN210982692U - Reliability testing device for power supply unit of intelligent electric meter - Google Patents

Reliability testing device for power supply unit of intelligent electric meter Download PDF

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CN210982692U
CN210982692U CN201921553288.XU CN201921553288U CN210982692U CN 210982692 U CN210982692 U CN 210982692U CN 201921553288 U CN201921553288 U CN 201921553288U CN 210982692 U CN210982692 U CN 210982692U
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power supply
supply unit
circuit
electric meter
reliability
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肖勇
张乐平
许卓
胡珊珊
王吉
王保帅
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CSG Electric Power Research Institute
China Southern Power Grid Co Ltd
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CSG Electric Power Research Institute
China Southern Power Grid Co Ltd
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Abstract

The embodiment of the application discloses smart electric meter electrical unit reliability test device includes: the device comprises a main control unit, a fast transient pulse group generating circuit, a surge impact voltage generating circuit, a temperature control circuit and a humidity control module, wherein the fast transient pulse group generating circuit, the surge impact voltage generating circuit, the temperature control circuit and the humidity control module are electrically connected with the main control unit; the fast transient pulse group generating circuit and the surge impact voltage generating circuit are connected to a mains supply through a control switch; the temperature control circuit and the humidity control circuit are also connected with the test box, and a plurality of power supply units are also arranged in the test box; one end of the power supply unit is connected with the commercial power through the control switch, and the other end of the power supply unit is connected with the voltage acquisition circuit. The problem that current smart electric meter has power supply unit reliability testing arrangement to lack has been solved to this application.

Description

Reliability testing device for power supply unit of intelligent electric meter
Technical Field
The application relates to the technical field of power supply testing, in particular to a device for testing reliability of a power supply unit of an intelligent electric meter.
Background
The statistical data of the faults of the intelligent electric meter show that the faults of the power supply unit occupy a large proportion, and meanwhile, the power supply unit is electrically connected with other units in the electric meter, so that other device problems caused by power supply problems are also in a large proportion. The high failure rate of the power supply unit and the high failure rate of other units related to the power supply unit cause the reliability test problem of the power supply unit module to enter our view. The current reliability test is usually specific to the whole intelligent electric meter, few tests are carried out on specific devices and units, and no device for independently carrying out the reliability test on the power supply unit exists, so that the requirements on corresponding test technologies and devices are reflected.
The technical specification of components for the electric energy meter is provided by southern power grid company in 2019, the specification lists the quality requirements of 15 key components for the electric energy meter and a test method of corresponding indexes, and the test method comprises the following steps: electrolytic capacitor, piezoresistor, resistor, photoelectric coupler, crystal resonator, transient diode, battery, load switch, chip capacitor, LCD, RS485, clock chip, controller, metering chip and current transformer.
The electric energy meter gives requirements and evaluation as characteristic indexes of the components by using 15 key component technical specifications, and the service life index of the electric energy meter is the service life index evaluation of the whole intelligent electric meter. The power supply unit of the intelligent electric meter is used as a very important unit with a high failure rate of the intelligent electric meter, the reliability of the power supply unit is related to the characteristics of a single component, and meanwhile, the reliability of the power supply unit is greatly determined by the design of a main power supply circuit and the matching of parameters among the components. Therefore, the reliability evaluation of the power supply unit of the smart meter needs a special test, and a reference standard and a reliability test device for describing the technical standard of the power supply unit of the smart meter are not available at present.
Disclosure of Invention
The embodiment of the application provides a reliability testing device for a power supply unit of an intelligent electric meter, and solves the problem that the existing reliability testing device for the power supply unit of the intelligent electric meter is missing.
In view of this, the first aspect of the present application provides a device for testing reliability of a power supply unit of a smart meter, the device including:
the device comprises a main control unit, a fast transient pulse group generating circuit, a surge impact voltage generating circuit, a temperature control circuit and a humidity control module, wherein the fast transient pulse group generating circuit, the surge impact voltage generating circuit, the temperature control circuit and the humidity control module are electrically connected with the main control unit;
the fast transient pulse group generating circuit and the surge impact voltage generating circuit are connected to mains supply through a control switch;
the temperature control circuit and the humidity control circuit are also connected with the test box, and a plurality of power supply units are also arranged in the test box;
one end of the power supply unit is connected with the commercial power through the control switch, and the other end of the power supply unit is connected with the voltage acquisition circuit.
Preferably, the apparatus further comprises a decoupling circuit; the fast transient pulse group generating circuit and the surge impact voltage generating circuit are connected with a mains supply sequentially through the control switch and the decoupling circuit.
Preferably, the apparatus further comprises a decoupling circuit; and the power supply unit is connected with the mains supply sequentially through the control switch and the decoupling circuit.
Preferably, the apparatus further comprises a voltage regulation circuit; the power supply unit is connected with the mains supply sequentially through the control switch, the voltage adjusting circuit and the decoupling circuit.
Preferably, the voltage regulation range of the voltage regulation circuit is 0.8Un to 1.5 Un.
Preferably, the power supply unit is grounded via an adjustable load.
Preferably, the system also comprises a display screen and a signal processing module; the display screen is connected with the voltage acquisition circuit through the signal processing module.
Preferably, the test chamber comprises 30 power supply units.
Preferably, the temperature adjusting range of the temperature adjusting circuit is-60 ℃ to +180 ℃.
Preferably, the humidity adjusting range of the humidity adjusting module is 5% -95%.
According to the technical scheme, the embodiment of the application has the following advantages: the application provides a reliability testing device for a power supply unit of an intelligent ammeter, which comprises a main control unit, a fast transient pulse group generating circuit, a surge impact voltage generating circuit, a temperature control circuit and a humidity control module, wherein the fast transient pulse group generating circuit, the surge impact voltage generating circuit, the temperature control circuit and the humidity control module are electrically connected with the main control unit; the fast transient pulse group generating circuit and the surge impact voltage generating circuit are connected to a mains supply through a control switch; the temperature control circuit and the humidity control circuit are also connected with the test box, and a plurality of power supply units are also arranged in the test box; one end of the power supply unit is connected with the commercial power through the control switch, and the other end of the power supply unit is connected with the voltage acquisition circuit. According to the device, the device for testing the power supply unit of the intelligent electric meter by arranging the characteristic index testing modules makes up for the defect that the current intelligent electric meter is provided with the power supply unit reliability testing device.
Drawings
Fig. 1 is a schematic structural diagram of an embodiment of a device for testing reliability of a power supply unit of an intelligent electric meter according to the present application.
Detailed Description
According to the device, the device for testing the power supply unit of the intelligent electric meter by arranging the characteristic index testing modules makes up for the defect that the current intelligent electric meter is provided with the power supply unit reliability testing device.
In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The technical solutions of the embodiments of the present application will be described clearly and completely with reference to the accompanying drawings, and it is obvious that the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without any creative effort belong to the protection scope of the embodiments in the present application.
For convenience of understanding, please refer to fig. 1, fig. 1 is a schematic structural diagram of an embodiment of a device for testing reliability of a power supply unit of an intelligent electric meter according to the present application, as shown in fig. 1, fig. 1 includes:
the device comprises a main control unit, a fast transient pulse group generating circuit, a surge impact voltage generating circuit, a temperature control circuit and a humidity control module, wherein the fast transient pulse group generating circuit, the surge impact voltage generating circuit, the temperature control circuit and the humidity control module are electrically connected with the main control unit.
The fast transient pulse group generating circuit and the surge impact voltage generating circuit are connected to the mains supply through the control switch.
It should be noted that, in order to test each index of the power supply, a control switch needs to be separately provided for each test index module, so that a single performance index can be tested separately.
The temperature control circuit and the humidity control circuit are also connected with the test box, and a plurality of power supply units are further arranged in the test box.
It should be noted that, in order to test the performance indexes of the power supply in the test chamber under different temperature and humidity performances, the power supply may be disposed in the sealed test chamber, and the temperature and humidity may be adjusted in the test chamber. The temperature and humidity can be adjusted by the main control unit in a programmed way, and can also be adjusted to the required testing temperature and humidity by an operator.
One end of the power supply unit is connected with the commercial power through the control switch, and the other end of the power supply unit is connected with the voltage acquisition circuit.
It should be noted that, in the test box, a plurality of power supply units may be tested at the same time, or a single power supply unit may be tested, so that each power supply unit needs to be provided with a switch connected to the mains supply. The switch can be controlled by the main control unit, and the power supply unit to be tested can be controlled by an operator. In addition, voltage signals on the tested power supply unit are collected through the voltage collecting circuit, so that corresponding test data can be obtained in real time, each performance index is evaluated, and the reliability of the power supply of the intelligent electric meter is judged.
According to the device, the device for testing the power supply unit of the intelligent electric meter by arranging the characteristic index testing modules makes up for the defect that the current intelligent electric meter is provided with the power supply unit reliability testing device.
In a specific embodiment, the specific test of the device for testing the reliability of the power supply unit of the smart meter comprises the following steps:
the device comprises a main control unit, a fast transient pulse group generating circuit, a surge impact voltage generating circuit, a temperature control circuit and a humidity control module, wherein the fast transient pulse group generating circuit, the surge impact voltage generating circuit, the temperature control circuit and the humidity control module are electrically connected with the main control unit; the fast transient pulse group generating circuit and the surge impact voltage generating circuit are connected to the mains supply through the control switch; the temperature control circuit and the humidity control circuit are also connected with the test box, and a plurality of power supply units are also arranged in the test box; one end of the power supply unit is connected with the commercial power through the control switch, and the other end of the power supply unit is connected with the voltage acquisition circuit.
It should be noted that, when testing, the fast transient burst generation circuit is characterized by: the peak phase voltage can be +/-4 kV (and can be set between 0 kV and 4 kV), Tr/Th (wave front time/half peak time) can be 5/50ns, and the repetition frequency can reach 5 kHz. The module has an interface n31 with the outside, when not performing the test, k1 is connected with n1,. k30 is connected with n30, k31 is disconnected, the interface is not connected; when the fast transient pulse impact test is carried out, k31 is connected with n31, a switch km (m is more than or equal to 1 and less than or equal to 30) of the power supply unit to be tested is connected with n31, and the rest is unchanged. The impact times and related parameters are controlled by the main control unit.
The surge voltage generation circuit is characterized in that: the peak phase voltage can be +/-4 kV (and can be set between 0 and 4 kV); the peak line voltage may be + -2 kV (and may be set between 0-2 kV), and Tr/Th may be 1.2/50 (8/20). The module has an interface n32 with the outside, when not performing the test, k1 is connected with n1,. k30 is connected with n30, k31 is disconnected, the interface is not connected; when the surge impulse voltage test is carried out, k31 is connected with n32, a switch km (m is more than or equal to 1 and less than or equal to 30) of the power supply unit to be tested is connected with n32, and the rest is unchanged. The impact times and specific parameters are controlled by the main control unit.
In a specific embodiment, the system further comprises a decoupling circuit, and the fast transient pulse group generating circuit and the surge impulse voltage generating circuit are connected with the mains supply through the control switch and the decoupling circuit in sequence. Wherein the decoupling circuit may be a common decoupling circuit.
It should be noted that, because the commercial power has harmonic components and other interference, in order to avoid the output signals generated by the fast transient pulse group generating circuit and the surge impulse voltage generating circuit from being interfered, a decoupling circuit is required to be provided to remove the harmonic components and other interference in the commercial power, and provide non-interfering 220V commercial power.
In a specific embodiment, the power supply unit is connected to the mains supply via a control switch and a decoupling circuit in that order.
It should be noted that, since the commercial power has harmonic components and other interference, in order to provide an interference-free voltage signal to the power supply unit, a decoupling circuit is required to remove the harmonic components and other interference in the commercial power and provide an interference-free 220V commercial power.
In a specific embodiment, the device further comprises a voltage regulation circuit; the power supply unit is connected with the mains supply sequentially through the control switch, the voltage adjusting circuit and the decoupling circuit.
It should be noted that the voltage adjusting module can simultaneously provide the working voltages of 30 power supply units in the test area, the voltages are adjustable within the range of 0.8 Un-1.5 Un (Un refers to the rated voltage of the commercial power), and the voltage adjusting module is connected with or disconnected from each power supply unit in the test area through switches K1-K30, wherein the voltage adjusting circuit can provide the voltage with the frequency of 50Hz, the voltage range is 0.8 Un-1.5 Un (Un refers to the rated voltage of the commercial power), the voltage can be continuously and uniformly adjusted, and the specific voltage size and the test time are set according to the test requirements.
In a specific embodiment, the power supply unit is connected to ground via an adjustable load.
It should be noted that each unit is independently connected to its own load, and the load can be adjusted in the range of 0 to 3 times the rated load.
In a specific embodiment, the system further comprises a display screen and a signal processing module; the display screen is connected with the voltage acquisition circuit through the signal processing module.
It should be noted that the test signal of the power supply unit is processed by the signal processing module to obtain a real-time numerical value of the test signal, and the real-time numerical value is displayed on the display screen. The signal processing circuit may be a common signal processor, such as a DSP processor.
In a specific embodiment, the temperature control circuit has a temperature adjustment range of-60 ℃ to +180 ℃.
It should be noted that the temperature control circuit is characterized in that: the temperature adjustable range is-60 ℃ to +180 ℃, and the temperature control circuits can be arranged at a plurality of positions of the test box, so that the temperature in the whole device is distributed as uniformly as possible, and the temperature can be adjusted uniformly.
In a specific embodiment, the humidity adjustment range of the humidity adjustment module is 5% -95%.
It should be noted that the humidity adjusting module can be disposed at a plurality of positions of the test chamber, so that the humidity in the whole test device is uniformly distributed, and the humidity can be uniformly adjusted.
In a specific embodiment, for example, the temperature intensification test may be performed by setting an initial temperature to 40 ℃ (which is a temperature value within a normal operating range), setting an end temperature to 120 ℃, setting a temperature step to 10 ℃, setting a temperature variability to 2.5 ℃/min, performing an online test after each temperature class is kept for 2 hours, recovering to room temperature (25 ℃) after the test is completed, performing an offline test after a basic error measurement value is stable, and performing an online test of the next temperature class after the offline test is completed. In the test process, the humidity of the test environment is kept at 45%, and in the test process, the load current introduced into the single-phase intelligent electric energy meter is 10A (reference current).
The test items are classified into a test item before a strengthening test, a test item after a strengthening test and a test item after a strengthening test.
The test items before the strengthening test are that a test sample needs to be verified before an on-line test, and the test items comprise an accuracy requirement test, an insulation test and a function and consistency test. And (5) ensuring that all test pieces can be subjected to a strengthening test after being qualified.
The reinforcement test items include online test items and offline test items. The online test items comprise basic errors, daily timing errors, error variation, error consistency, load ascending and descending variation, display and communication. The off-line error test items comprise all on-line test items, and also comprise electric meter constant, starting, shunt running and influence quantity tests. The on-line test items kept under the action of the high-temperature stress level mainly comprise verification items and other related items which have problems in the strengthening and thorough-investigation test, and the aim is to find out the main failure mode which can be excited by the high-temperature stress as comprehensively as possible. The off-line test items restored to the room temperature condition include all on-line test items and test items of partial full-inspection acceptance tests. All high-temperature stress action results are converted into a normal working range of the electric energy meter for comparison, statistical analysis is facilitated, and the degradation trend and the working limit of the single-phase intelligent electric energy meter after the high-temperature stress action are found out.
The test items after the strengthening test comprise that after the strengthening test is finished, a full-performance test of the single-phase intelligent electric energy meter is carried out in a room-temperature off-line environment, test data are recorded in real time, and the performance of the single-phase intelligent electric energy meter is comprehensively examined.
In a similar way, the device can also be used for performing reliability tests for checking the power supply unit in multiple aspects such as impact current stability, impact service life, high-voltage tolerance capability, high and low temperature, high humidity, damp and hot, load and the like on the power supply module of the intelligent electric meter.
The invention makes up the blank that the reliability test cannot be carried out on the power supply unit in the prior reliability test device, can carry out the reliability test on the power supply unit of the intelligent ammeter from the aspects of impact current tolerance, power frequency voltage tolerance, high temperature, high humidity tolerance and the like, and has positive effects of improving the quality of the power supply unit and reducing the failure rate of the intelligent ammeter.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
The terms "comprises," "comprising," and "having," and any variations thereof, in the description and claims of this application, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.
The above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.

Claims (10)

1. The utility model provides a smart electric meter electrical unit reliability test device which characterized in that includes: the device comprises a main control unit, a fast transient pulse group generating circuit, a surge impact voltage generating circuit, a temperature control circuit and a humidity control module, wherein the fast transient pulse group generating circuit, the surge impact voltage generating circuit, the temperature control circuit and the humidity control module are electrically connected with the main control unit;
the fast transient pulse group generating circuit and the surge impact voltage generating circuit are connected to mains supply through a control switch;
the temperature control circuit and the humidity control module are also connected with the test box, and a plurality of power supply units are also arranged in the test box;
one end of the power supply unit is connected with the commercial power through the control switch, and the other end of the power supply unit is connected with the voltage acquisition circuit.
2. The device for testing the reliability of the power supply unit of the intelligent electric meter according to claim 1, wherein the device further comprises a decoupling circuit;
the fast transient pulse group generating circuit and the surge impact voltage generating circuit are connected with a mains supply sequentially through the control switch and the decoupling circuit.
3. The device for testing the reliability of the power supply unit of the intelligent electric meter according to claim 1, wherein the device further comprises a decoupling circuit;
and the power supply unit is connected with the mains supply sequentially through the control switch and the decoupling circuit.
4. The device for testing the reliability of the power supply unit of the intelligent electric meter according to claim 3, wherein the device further comprises a voltage regulation circuit;
the power supply unit is connected with the mains supply sequentially through the control switch, the voltage adjusting circuit and the decoupling circuit.
5. The device for testing the reliability of the power supply unit of the intelligent electric meter according to claim 4, wherein the voltage adjusting range of the voltage adjusting circuit is 0.8Un to 1.5 Un.
6. The device for testing the reliability of the power supply unit of the intelligent electric meter according to claim 1, wherein the power supply unit is grounded through an adjustable load.
7. The device for testing the reliability of the power supply unit of the intelligent electric meter according to claim 1, further comprising a display screen and a signal processing module;
the display screen is connected with the voltage acquisition circuit through the signal processing module.
8. The device for testing the reliability of the power supply unit of the intelligent electric meter as claimed in claim 1, wherein 30 power supply units are specifically included in the test chamber.
9. The device for testing the reliability of the power supply unit of the intelligent electric meter according to claim 1, wherein the temperature regulation range of the temperature control circuit is-60 ℃ to +180 ℃.
10. The device for testing the reliability of the power supply unit of the intelligent electric meter according to claim 1, wherein the humidity adjusting range of the humidity control module is 5% -95%.
CN201921553288.XU 2019-09-18 2019-09-18 Reliability testing device for power supply unit of intelligent electric meter Active CN210982692U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115047926A (en) * 2022-05-30 2022-09-13 上海飞奥燃气设备有限公司 Automatic testing system and method for reliability of electric edge environment

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115047926A (en) * 2022-05-30 2022-09-13 上海飞奥燃气设备有限公司 Automatic testing system and method for reliability of electric edge environment

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