A power source for surge test and a surge test method of a direct current energy meter

Abstract

The application discloses a power source for surge test and a surge test method of a direct-current electric energy meter. The power source has two output ports. One output port outputs a test voltage signal with a surge and a corresponding test current signal, and the other output port outputs a reference voltage signal without a surge and a corresponding reference current signal. The frequency and amplitude of the test voltage signal in a non-surge wave band are the same as those of the reference voltage signal, and the frequency and amplitude of the test voltage signal in a surge wave band are different from those of the reference voltage signal, so as to simulate possible voltage surge conditions. The application is applied to the field of electric energy meter performance test. In the surge test process, the reference voltage signal can be used as a control group to analyze and compare the surge resistance performance of the to-be-tested electric energy meter, so that the surge test result of the to-be-tested direct-current electric energy meter can be directly obtained, the surge event can be customized to meet specific test requirements, the surge test cost of the direct-current electric energy meter is reduced, and the feasibility and flexibility of the surge test are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power sources, and more particularly, to a power source for surge test and a surge test method of a direct current energy meter. BACKGROUND

[0002] Energy meters are crucial devices in the power system, used to measure the consumption of electrical energy, ensuring accurate metering of electricity supply. Energy meters not only provide accurate energy metering for power providers and users, but also contribute to the monitoring and management of the power system. Energy meters play a central role in various power applications, including household electricity, industrial production, commercial premises, etc. Therefore, the accuracy and reliability of energy meters are crucial for the operation and monitoring of the power system.

[0003] The performance stability and accuracy of energy meters have a significant impact on the fairness and transparency of the electricity market. However, power quality problems prevalent in the power system, such as voltage surges and current surges, can have a negative impact on the performance of energy meters. Power quality problems are caused by a variety of factors, including internal operation and equipment failure of the power system, as well as external factors such as weather conditions and lightning, etc. These problems lead to distortion and instability of the power waveform, which can cause errors and performance degradation of energy meters. Voltage surges are a major aspect of power quality problems, which are usually transient events, and the high-energy transient voltage and current generated can cause energy meters to malfunction or inaccurate metering. Therefore, in order to ensure the accurate metering and reliable operation of energy meters under unstable power conditions, surge testing has become a crucial task.

[0004] Traditional surge testing methods usually require the use of specific test equipment and devices, including voltage surge generators and current surge generators. These test equipment simulates the surge events that may occur in the power system by generating high-energy, high-frequency voltage and current waveforms. Energy meters are then connected to these test equipment to evaluate their resistance and performance under surge events. However, traditional surge testing methods have many limitations and challenges.

[0005] Firstly, the complexity and high cost of traditional testing methods are unbearable for many laboratories and power service providers. These methods usually require a large amount of equipment and resources, including high-energy power sources, complex circuits and control systems. This results in high costs of surge testing, limiting its widespread application.

[0006] Secondly, traditional testing methods can usually only simulate specific types and levels of surge events, making it difficult to meet different testing needs. Various types of surge events may occur in power systems, including events of different frequencies, amplitudes, and waveforms. Therefore, a more flexible method is needed to meet different testing needs to ensure that the electric energy meter can work normally in various situations.

[0007] In addition, the operation of traditional surge test equipment usually requires professional technicians, and the operation process is complicated. This increases the cost of manpower and time, limiting the wide application of surge tests. A more simplified operation method is needed to enable more laboratories and testing institutions to conduct surge tests without the need for specially trained technicians.

[0008] Finally, the data generated by traditional testing devices is difficult to analyze and compare. Data processing and analysis require complex software and skills, including waveform analysis, data comparison, and statistical analysis. This increases the complexity of the testing process, which may lead to difficulties in data analysis. Therefore, a more simplified data analysis method is needed to speed up the result analysis and report generation process of the surge test.

[0009] Therefore, a new, more efficient, and cost-effective surge test method and device is needed to address the challenges of electric energy meter performance evaluation. This method should have higher flexibility to meet the testing needs of different types and levels of surge events, while also having a more simplified operation and data analysis process to reduce costs and improve feasibility. SUMMARY

[0010] According to the present application, a power source for surge testing and a surge testing method for direct current electric energy meters are provided to solve the technical problems of traditional surge testing methods, which are costly, can usually only simulate specific types and levels of surge events, making it difficult to meet different testing needs, require professional technicians, and have a complicated operation process, which increases the cost of manpower and time, limiting the wide application of surge tests, and the complexity of the testing process.

[0011] According to a first aspect of the present application, a power source for surge testing is provided, comprising:

[0012] The power source has two output ports, one of which outputs a test voltage signal with a surge and its corresponding test current signal, and the other outputs a reference voltage signal without a surge and its corresponding reference current signal;

[0013] The test voltage signal has the same frequency and amplitude as the reference voltage signal in a non-inrush wave band, and has different frequency and amplitude from the reference voltage signal in an inrush wave band, so as to simulate the voltage inrush condition that may occur in the power system, and take the reference voltage signal as a control group.

[0014] The power source comprises:

[0015] A signal generation module is configured to generate and output two voltage signals with the same frequency and amplitude, and take the two voltage signals as the reference voltage signal and the test voltage signal respectively.

[0016] An inrush generation module is configured to load a voltage inrush event on the output path of the test voltage signal.

[0017] A control system is configured to ensure that the signal generation module and the inrush generation module generate synchronized signals, and dynamically adjust the amplitude and frequency to realize various test conditions.

[0018] A current signal module is configured to generate a test current signal corresponding to the test voltage signal, and a reference current signal corresponding to the reference voltage signal.

[0019] The signal generation module comprises:

[0020] A signal generator is configured to generate a signal waveform of the analog voltage signal.

[0021] A brancher is configured to divide the analog voltage signal generated by the signal generator into two output paths, and take the two output paths as the test voltage signal and the reference voltage signal respectively.

[0022] The power source further comprises:

[0023] An isolation circuit is arranged on the transmission path of the test voltage signal to the inrush generation module, so as to isolate the brancher and the signal generator, and avoid the influence of the inrush on the brancher and the signal generator.

[0024] Optionally, the inrush generation module comprises:

[0025] A pulse generation circuit is configured to generate a pulse signal with adjustable frequency and duty cycle.

[0026] A variable gain amplification circuit is electrically connected to the output end of the pulse generation circuit, and is configured to adjust the amplitude of the pulse signal.

[0027] A waveform conversion circuit is electrically connected to the output end of the variable gain amplification circuit, and is configured to generate a pulse signal corresponding to various types and intensities of voltage inrush events.

[0028] An adder, electrically connected with the waveform conversion circuit and the signal generation module, is configured to load the pulse signal on the test voltage signal to simulate a voltage surge event.

[0029] Optionally, the power source further comprises:

[0030] A first amplification circuit is arranged in a transmission path of the test voltage signal and configured to perform adjustable gain amplification processing on the test voltage signal.

[0031] Optionally, the power source further comprises a second amplification circuit arranged in a transmission path of the reference voltage signal and configured to perform adjustable gain amplification processing on the reference voltage signal.

[0032] Optionally, the power source further comprises:

[0033] A first filter circuit is arranged in a transmission path of the test voltage signal and configured to filter out high-frequency noise and stray signals in the test voltage signal.

[0034] Optionally, the power source further comprises a second filter circuit arranged in a transmission path of the reference voltage signal and configured to filter out high-frequency noise and stray signals in the reference voltage signal.

[0035] Optionally, the isolation circuit comprises an input end IN1, an operational amplifier OA1-1, a linear optocoupler, an operational amplifier OA1-2, and an output end OUT1.

[0036] The linear optocoupler comprises pins 1-6, and is internally provided with an LED, a PD1, and a PD2, wherein the positive and negative electrodes of the LED are connected to pins 1 and 2 respectively, the positive and negative electrodes of the PD1 are connected to pins 4 and 3 respectively, and the positive and negative electrodes of the PD2 are connected to pins 5 and 6 respectively.

[0037] In the signal input direction of the isolation circuit, the input end IN1 is connected to the inverting input end of the operational amplifier OA1-1, the non-inverting input end of the operational amplifier OA1-1 is grounded, the output end of the operational amplifier OA1-1 is connected to pin 1, pins 1 and 2 are connected to a power supply, pin 3 is grounded, and pin 4 is connected to the inverting input end of the operational amplifier OA1-1.

[0038] In the signal output direction of the isolation circuit, the inverting input end of the operational amplifier OA1-2 is connected to pin 6, the non-inverting input end and the ground terminal of the operational amplifier OA1-2 and pin 5 are all grounded, the power supply terminal of the operational amplifier OA1-2 is connected to a power supply, and the output end OUT1 is connected to the output end of the operational amplifier OA1-2.

[0039] Optionally, the isolation circuit comprises an input end IN2, an operational amplifier OA2-1, a linear optocoupler, an operational amplifier OA2-2, and an output end OUT2.

[0040] The linear light coupling device comprises No. 1-6 pins, and is internally provided with an LED, a PD1 and a PD2, wherein the positive and negative electrodes of the LED are connected with No. 1 and 2 pins respectively, the positive and negative electrodes of the PD1 are connected with No. 4 and 3 pins respectively, and the positive and negative electrodes of the PD2 are connected with No. 5 and 6 pins respectively;

[0041] In the signal input direction of the isolation circuit, the input end IN2 is connected with the inverting input end of the operational amplifier OA2-1, the output end of the operational amplifier OA2-1 is connected with No. 2 pin, No. 1 pin is grounded, the non-inverting input end of the operational amplifier OA2-1 is grounded through the resistance R2-2, No. 4 pin is grounded, and No. 3 pin is connected with the power supply;

[0042] In the signal output direction of the isolation circuit, No. 6 pin is connected with the power supply, No. 5 pin is connected with the non-inverting input end of the operational amplifier OA2-2 and grounded through the resistance R2-3 at the same time, the power supply end of the operational amplifier OA2-2 is connected with the power supply, and the inverting input end and the output end of the operational amplifier OA2-2 are connected with the output end OUT2.

[0043] According to another aspect of the present application, a surge test method of a direct current electric energy meter is also provided, comprising:

[0044] The to-be-tested electric energy meter is connected to the first output port of the power source to obtain a test voltage signal and a test current signal, and the standard electric energy meter is connected to the second output port of the power source to obtain a reference voltage signal and a reference current signal;

[0045] The amplitudes, frequencies, surge event types and intensities of the test voltage signal, the test current signal, the reference voltage signal and the reference current signal are set;

[0046] The power source is started, the test is started based on the test voltage signal, the test current signal, the reference voltage signal and the reference current signal, and the response data of the to-be-tested electric energy meter and the standard electric energy meter are collected during the test;

[0047] After the test is completed, the power source is turned off, and the response data of the standard electric energy meter is taken as a control group to analyze the surge resistance performance of the to-be-tested electric energy meter.

[0048] Optionally, the response data of the standard electric energy meter is taken as a control group to analyze the surge resistance performance of the to-be-tested electric energy meter, comprising:

[0049] The current and voltage waveforms of the to-be-tested electric energy meter and the standard electric energy meter during the surge event are compared; and / or

[0050] Whether the to-be-tested electric energy meter can maintain the accuracy of the response data during the surge event is checked; and / or

[0051] evaluate whether the to-be-tested electric energy meter can quickly recover to a normal working state after the end of the surge event; and / or

[0052] evaluate whether the to-be-tested electric energy meter has an effective surge event detection and alarm system; and / or

[0053] evaluate the persistence and tolerance of the to-be-tested electric energy meter under the surge event.

[0054] The power source in the application has two output ports, which can simultaneously output a test voltage signal with a surge and a corresponding test current signal, and a reference voltage signal without a surge and a corresponding reference current signal. Since the frequency and amplitude of the test voltage signal in the non-surge band are the same as those of the reference voltage signal, and the frequency and amplitude of the test voltage signal in the surge band are different from those of the reference voltage signal, in the surge test method of the direct current electric energy meter in the application, the reference voltage signal and the corresponding reference current signal can be used as a control group to analyze and compare the anti-surge performance of the to-be-tested direct current electric energy meter, so that the surge test result of the to-be-tested direct current electric energy meter can be more intuitively obtained.

[0055] In the preferred scheme of the power source in the application, various circuit structures capable of generating voltage surge events of various types and intensities are arranged in the surge generation module. Not only can different types and intensities of voltage surge events be simulated, but also the surge events can be customized according to specific requirements to meet specific test requirements, thereby improving flexibility. In the surge test method of the direct current electric energy meter, the surge events can also be customized according to specific requirements to meet specific test requirements, thereby improving flexibility, reducing the cost of the surge test of the direct current electric energy meter, and improving the feasibility of the surge test. It can be more widely applied to the electric energy meter industry, promote the development of electric energy meters, and improve the stability and reliability of the power system. BRIEF DESCRIPTION OF DRAWINGS

[0056] The exemplary embodiments of the application can be more completely understood by referring to the following drawings:

[0057] Figure 1 The structure block diagram of the power source for the surge test in the embodiment of the application;

[0058] Figure 2 The circuit structure schematic diagram of the linear optocoupler device in the embodiment of the application;

[0059] Figure 3 The first embodiment schematic diagram of the isolation circuit in the embodiment of the application;

[0060] Figure 4 The second embodiment schematic diagram of the isolation circuit in the embodiment of the application;

[0061] Figure 5 Fig. 1 is a schematic diagram of a pulse generating circuit according to an embodiment of the present application;

[0062] Figure 6 Fig. 2 is a schematic diagram of a variable gain amplification circuit according to an embodiment of the present application;

[0063] Figure 7 Fig. 3 is a schematic diagram of a rectangular wave-triangle wave conversion circuit according to an embodiment of the present application;

[0064] Figure 8 Fig. 4 is a schematic diagram of a rectangular wave-saber wave conversion circuit according to an embodiment of the present application;

[0065] Figure 9 Fig. 5 is a schematic diagram of a total circuit structure of a surge generating module according to an embodiment of the present application;

[0066] Figure 10 Fig. 6 is a flow chart of a surge test method of a direct current energy meter according to an embodiment of the present application.

[0067] The accompanying drawings are included to provide a further understanding of the present application, and are incorporated herein and constitute a part of this application. The drawings illustrate embodiments of the present application and, together with the description, serve to explain the principles of the present application. In the drawings: DETAILED DESCRIPTION

[0068] Reference will now be made to the drawings to describe the exemplary embodiments of the present application in detail. The present application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art. Like reference numerals refer to like elements throughout the specification. It will be understood that when a

[0069] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0070] All directional indications (such as upper, lower, left, right, front, rear, etc.) given herein are only used for the purpose of explanation and are in no way limiting to the present application. The directional indications are relative to the relative position relationship, movement, etc. between the components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications will also change accordingly.

[0071] In addition, the descriptions such as "first", "second", etc. in the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can be explicitly or implicitly included at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0072] According to a first aspect of the present application, a power source for surge test is provided, such as Figure 1 A power source for surge test is shown in the present embodiment, which has two output ports 5, one of which outputs a test voltage signal with surge and its corresponding test current signal, and the other outputs a reference voltage signal without surge and its corresponding reference current signal. Among them, the frequency and amplitude of the test voltage signal in the non-surge band are the same as those of the reference voltage signal, and the frequency and amplitude of the test voltage signal in the surge band are different from those of the reference voltage signal. The power source in the present embodiment can be applied to the surge test of DC energy meter. In the surge test, the voltage and current surge conditions that may occur in the power system are simulated through the test voltage signal and its corresponding test current signal, and the reference voltage signal and its corresponding reference current signal are used as the control group of the surge test to analyze and compare the anti-surge performance of the DC energy meter under test, so that the surge test results of the DC energy meter under test can be obtained more intuitively, and the power source and surge generator no longer need to be set up separately, reducing the test cost.

[0073] It is worth noting that the two output ports 5 of the power source in the present embodiment can be output simultaneously or individually. For example, if a surge test with control group is needed for the DC energy meter, the two output ports 5 of the power source can be controlled to output the test voltage signal and its corresponding test current signal, as well as the reference voltage signal and its corresponding reference current signal simultaneously. If the power source in the present embodiment is used as a power standard source, the line of the output port 5 corresponding to the test voltage signal and its corresponding test current signal can be closed, and only the reference voltage signal and its corresponding reference current signal can be kept on. If the power source in the present embodiment is used as a surge generator, the line of the output port 5 corresponding to the reference voltage signal and its corresponding reference current signal can be closed, and only the test voltage signal and its corresponding test current signal can be kept on.

[0074] In the present embodiment, the power source mainly includes a signal generation module 1, a surge generation module 2, a control system 3 and a current signal module 4.

[0075] The signal generation module 1 is mainly used for generating and outputting two voltage signals with the same frequency and amplitude, which are used as the reference voltage signal and the test voltage signal respectively. In the signal generation stage of the signal generation module 1, the test voltage signal is not loaded with surge, that is, the reference voltage signal and the test voltage signal are completely consistent at this time.

[0076] The surge generation module 2 is arranged in the transmission path of the test voltage signal and is mainly used for loading the test voltage signal with surge events such as front surge, sharp top surge, overvoltage, voltage sag, instantaneous interruption, voltage fluctuation and / or voltage harmonic, etc. The loading form of the front surge is to make the voltage of the test voltage signal in a local band instantaneously rise from zero to peak value in a short time, which is used to simulate the surge caused by the switching operation of the power switch or other devices. The loading form of the sharp top surge is to load the edge of steep rise and fall on the local band of the test voltage signal, which is used to simulate the surge caused by the sudden load switch, arc flashover or lightning discharge. The loading form of the overvoltage is to make the transient increase of the voltage waveform of the test voltage signal in a local band, which is used to simulate the surge caused by system failure, lightning hitting power line, voltage recovery or other reasons. The loading form of the voltage sag is to make the voltage of the test voltage signal in a local band decrease in a short time. The loading form of the instantaneous interruption is to make the voltage of the test voltage signal in a local band suddenly interrupted and then recovered, which is used to simulate the surge caused by transient failure, overload or short circuit in the power system. The loading form of the voltage fluctuation is to make the voltage waveform of the test voltage signal in a local band change periodically or randomly, which is used to simulate the surge caused by the start or stop of large load. The loading form of the voltage harmonic is to make the voltage waveform of the test voltage signal in a local band contain harmonic components with frequency being integer times of the fundamental frequency, which is used to simulate the surge caused by harmonic sources in the nonlinear load, electronic device or power system.

[0077] The control system 3 is electrically connected with the signal generation module 1 and the surge generation module 2 respectively, which is used to ensure that the signal generation module 1 and the surge generation module 2 generate synchronous signals, and simultaneously perform dynamic adjustment of the amplitude and frequency to realize various test conditions. The current signal module 4 is electrically connected with the transmission paths of the test voltage signal and the reference voltage signal respectively, which is used to generate the test current signal corresponding to the test voltage signal and the reference current signal corresponding to the reference voltage signal, so that the finally generated test voltage signal and the corresponding test current signal are connected to one output port 5, and the reference voltage signal and the corresponding reference current signal are connected to another output port 5.

[0078] In this embodiment, the signal generating module 1 is composed of a signal generator 101 and a brancher 102. The signal generator 101 generates the signal waveform of the analog voltage signal, and the brancher 102 has an input end and two output ends. The input end is connected to the output end of the signal generator 101, and the two output ends output the analog voltage signal generated by the signal generator 101 as the test voltage signal and the reference voltage signal respectively. In the specific implementation process, the signal generator 101 can specifically adopt an analog function signal generator 101, a digital function signal generator 101, an arbitrary waveform signal generator 101, or an arbitrary waveform signal generator 101, etc.

[0079] As a preferred embodiment, the power source further comprises an isolation circuit 6. The isolation circuit 6 is arranged on the transmission path of the test voltage signal to the surge generating module 2, so as to isolate the brancher 102 and the signal generator 101, and avoid the influence of the surge on the brancher 102 and the signal generator 101. Further preferably, the power source further comprises a first amplification circuit 7, a second amplification circuit 8, a first filter circuit 9 and a second filter circuit 10. The first amplification circuit 7 is arranged on the transmission path of the test voltage signal, and is used for adjustable gain amplification processing of the reference voltage signal; the second amplification circuit 8 is arranged on the transmission path of the test voltage signal, and is used for adjustable gain amplification processing of the reference voltage signal; the first filter circuit 9 is arranged on the transmission path of the test voltage signal, and is used for filtering out high-frequency noise and stray signals in the test voltage signal; and the second filter circuit 10 is arranged on the transmission path of the test voltage signal, and is used for filtering out high-frequency noise and stray signals in the test voltage signal.

[0080] In this embodiment, the isolation circuit 6 mainly realizes the related functions through a linear optocoupler. Referring to Figure 2 The circuit structure diagram of the linear optocoupler has 8 pins, and has an LED and two matched photodiodes PD1 and PD2 inside. The positive and negative electrodes of the LED are connected to the 1st pin and the 2nd pin respectively, the positive and negative electrodes of the PD1 are connected to the 4th pin and the 3rd pin respectively, and the positive and negative electrodes of the PD2 are connected to the 5th pin and the 6th pin respectively. The input side photodiode PD1 is used to monitor the light intensity of the LED and keep it stable, and also eliminates the nonlinearity and temperature drift characteristics of the LED. The photoelectric current generated by the output side photodiode PD2 is also proportional to the light intensity generated by the LED. Through IC design, the light intensity received by the two photodiodes from the LED is basically equal, i.e. IPD2 = IPD1.

[0081] Referring to Figure 3 The circuit structure diagram of the isolation circuit 6 in the first embodiment of this embodiment includes an input end IN1, an operational amplifier OA1-1, a linear optocoupler N1, an operational amplifier OA1-2 and an output end OUT1.

[0082] In Figure 3 In the signal input direction of the isolation circuit 6 shown in the figure, IN1 is connected to the inverting input terminal of OA1-1 through resistor R1-1 to input a signal. The non-inverting input terminal of OA1-1 is grounded, and the output terminal of OA1-1 is connected to the 1st pin of N1. The 1st and 2nd pins of N1 are connected to the power supply through resistor R1-2. The 3rd pin of N1 is grounded, and the 4th pin is connected to the inverting input terminal of OA1-1 to feed back a signal. Capacitor C1-1 is connected between the inverting input terminal and the output terminal of OA1-1 to filter.

[0083] In Figure 3 In the signal output direction of the isolation circuit 6 shown in the figure, the inverting input terminal of OA1-2 is connected to the 6th pin of N1, and the non-inverting input terminal and the ground terminal of OA1-2 and the 5th pin of N1 are all grounded. Capacitor C1-2 and resistor R1-3 are connected in parallel between the inverting input terminal and the output terminal of OA1-2 to form an integrator circuit. The power supply terminal of OA1-2 is connected to the power supply, and capacitor C1-3 and capacitor C1-4 are connected in parallel between the power supply terminal and the ground to decouple the power supply and reduce high-frequency noise and fluctuations on the power supply line. OUT1 is connected to the output terminal of OA1-2 to output a signal.

[0084] OA1-1 adjusts LED current ILED to generate photocurrent IPD1, so that the inverting input terminal of OA1-1 is kept at 0V. When the input voltage of IN1 rises, the voltage at the inverting input terminal of OA1-1 will tend to rise. After being amplified by OA1-1, ILED and IPD1 will increase, and the increase of IPD1 will lower the voltage at the inverting input terminal of OA1-1 and keep it at 0V. According to the virtual break principle of the operational amplifier, all the current flowing through R1-1 flows through PD1, so IPD1 = VIN1 / R1-1. Therefore, IPD1 is determined only by the input voltage VIN and the input resistance R1-1, and is independent of the illumination intensity of the LED. When the illumination intensity of the LED drifts, OA1-1 will adjust IPD1 to keep it stable. Therefore, IPD1 and input voltage VIN maintain a good linear relationship. Since the light emitted by the LED is incident on both PD1 and PD2, IPD2 at the output terminal OUT1 will also remain stable. OA1-2 and R1-3 form a transimpedance amplifier to convert IPD1 into output voltage VOUT1, and the conversion relationship is VOUT1 / VIN1 = K3(R1-3 / R1-1), where K3 is the transfer gain of the optocoupler.

[0085] Reference Figure 4 The circuit structure diagram of the isolation circuit 6 in the second embodiment of the present embodiment is shown in the figure, which includes input terminal IN2, operational amplifier OA2-1, linear optocoupler N2, operational amplifier OA2-2, and output terminal OUT2.

[0086] In Figure 4 In the signal input direction of the isolation circuit 6 shown in the figure, IN2 is connected to the inverting input terminal of OA2-1, the output terminal of OA2-1 is connected to pin 2 of N2 through resistor R2-1, and pin 1 of N2 is grounded. The non-inverting input terminal of OA2-1 is grounded through resistor R2-2 and connected to the output terminal through circuit C2-1 for filtering. Pin 4 of N2 is grounded, and pin 3 is connected to the power supply.

[0087] In Figure 4 In the signal output direction of the isolation circuit 6 shown in the figure, pin 6 of N2 is connected to the power supply, and pin 5 is connected to the non-inverting input terminal of OA2-2 and grounded through resistor R2-3. The power supply terminal of OA2-2 is connected to the power supply, and circuit C2-2 and circuit C2-3 are connected in parallel between the power supply and ground for power supply decoupling to reduce high-frequency noise and fluctuations on the power supply line. The inverting input terminal and the output terminal of OA2-2 are connected to the output terminal OUT2 for outputting the signal.

[0088] OA2-1 adjusts the LED current ILED to generate a photo current IPD1, so that the inverting input terminal and the non-inverting input terminal of OA2-1 remain at the same level. When the input voltage of IN2 increases, OA2-1 amplifies it and makes the voltage at the output terminal increase, so ILED and IPD1 increase, and the increase in IPD1 makes the voltage at the inverting input terminal of OA2-1 increase and change with the input voltage. According to the virtual break principle, the voltage at the inverting input terminal of OA2-1 is equal to the voltage at the non-inverting input terminal, so IPD1 = VIN2 / R2-2. Therefore, IPD1 is determined only by the input voltage VIN and the input resistance R2-2, and is independent of the intensity of the LED light. When the intensity of the LED light drifts, OA2-1 adjusts IPD1 to keep it stable. Therefore, IPD1 and the input voltage VIN have a good linear relationship. At the output terminal, the photo current IPD2 generated by PD2 produces a voltage drop at R2-3, and the follower output formed by OA2-2 outputs a voltage signal VOUT2 / VIN2 = K3(R2-3 / R2-2), where K3 is the transmission gain of the optocoupler.

[0089] The specific circuit implementation structures of the amplification circuit and the filtering circuit are conventional technical means in the field, so they will not be described in detail in this embodiment.

[0090] In this embodiment, the surge generation module 2 includes a pulse generation circuit 201, a variable gain amplification circuit 202, a waveform conversion circuit 203, and an adder 204, which are used to edit various types and intensities of voltage surge events, such as front surge, sharp top surge, overvoltage, voltage sag, instantaneous interruption, voltage fluctuation, and / or voltage harmonic, etc. in the local wave band of the test voltage signal to meet different test requirements. Among them, the pulse generation circuit 201 is used to generate a pulse signal with adjustable frequency and duty cycle; the variable gain amplification circuit 202 is electrically connected with the output end of the pulse generation circuit 201, and is used to adjust the amplitude of the pulse signal; the waveform conversion circuit 203 is electrically connected with the output end of the variable gain amplification circuit 202, and is used to generate a pulse signal corresponding to various types and intensities of voltage surge events; and the adder 204 is electrically connected with the waveform conversion circuit 203 and the signal generation module, and is used to load the pulse signal on the test voltage signal to simulate the voltage surge event.

[0091] Reference Figure 5 The structure of the pulse generation circuit 201 in this embodiment is shown in the schematic diagram, which mainly includes a 555 timer N3, a resistor R3-1, a resistor R3-2, a capacitor C3, and an output end OUT3. Among them, the 555 timer has 8 pins, wherein the No. 1 pin is a GND pin for grounding, the No. 2 pin is a TRI pin for setting trigger flip, the No. 3 pin is an OUT pin for output, the No. 4 pin is a RST pin for low-level reset, the No. 5 pin is a CON pin for external control voltage, the No. 6 pin is a THR pin for reset, the No. 7 pin is a DIS pin for discharge, and the No. 8 pin is a VCC pin for connecting power supply. The circuit structure of the pulse generation circuit 201 in this embodiment is specifically as follows: the No. 8 pin of the 555 timer N3 is connected to the positive power supply voltage, and the No. 1 pin is grounded; the first end of the resistor R3-1 is connected with the No. 2 pin, the positive electrode of the capacitor C3 is connected with the second end of the resistor R3-1 and the No. 6 pin, the negative electrode of the capacitor C3 is grounded, and the No. 6 pin is connected with the No. 8 pin to charge the circuit C3; the two ends of the resistor R3-2 are respectively connected with the No. 6 pin and the No. 7 pin, the No. 5 pin is connected with the No. 8 pin, and the output end OUT3 is connected with the No. 3 pin.

[0092] In this embodiment, the calculation process of the frequency and duty cycle of the pulse signal generated by the pulse generation circuit 201 is as follows:

[0093] The frequency of the pulse signal is determined by the working principle of the resistor R3-1, the resistor R3-2, the capacitor C3, and the 555 timer, and is as follows:

[0094]

[0095] The duty cycle is determined by the proportion of the resistor R3-1 and the resistor R3-2, and is as follows:

[0096] fD fD

[0097] fDWherein, f is frequency, D is duty cycle.

[0098] Reference Figure 6 is the structure schematic diagram of variable gain amplification circuit 202 in this embodiment, it mainly includes input terminal IN4, operational amplifier OA4, digital potentiometer DCP, feedback resistance Rf and output terminal OUT4. Among them, input terminal IN4 is connected with positive phase input terminal of operational amplifier OA4, feedback resistance Rf is connected between inverting input terminal and output terminal of operational amplifier OA4 and constitutes feedback circuit, output terminal OUT4 is connected with output terminal of operational amplifier OA4, one side end of digital potentiometer DCP is connected on feedback circuit with sliding end, and the other side end is grounded.

[0099] Amplification gain of variable gain amplification circuit 202 in this embodiment is:

[0100]

[0101] Wherein, A is amplification gain, R DCP Resistance value of digital potentiometer DCP.

[0102] In this embodiment, waveform conversion circuit 203 includes rectangular wave-triangle wave conversion circuit, rectangular wave-knife wave conversion circuit. Among them, rectangular wave-triangle wave conversion circuit is mainly used to convert rectangular wave into the required triangle wave of analog surge, and rectangular wave-knife wave conversion circuit is mainly used to convert rectangular wave into the required knife wave of analog surge.

[0103] In the specific implementation process, rectangular wave-triangle wave conversion circuit adopts integration circuit, and it mainly includes input terminal IN5, operational amplifier OA5 and output terminal OUT5. Reference Figure 7 , input terminal IN5 is connected with inverting input terminal of operational amplifier OA5 through resistance R5-1, and positive phase input terminal of operational amplifier OA5 is grounded through resistance R5-2. Inverting input terminal of operational amplifier OA5 is connected with its output terminal through capacitor C5, and output terminal OUT5 is connected with output terminal of operational amplifier OA5. Inverting input terminal of operational amplifier OA5 is also connected with its output terminal through resistance R5-3. Among them, R5-3>10R5-1, to avoid that low frequency feedback resistance is infinite. Among them, R5-1 and C5 are integration time constant, and voltage V IN5 Of input terminal IN5 is inputted, voltage V OUT5 Of output terminal OUT5 is:

[0104]

[0105] Therefore, when the input signal of the rectangular wave-triangle wave conversion circuit is a rectangular wave, the output signal becomes a triangle wave, wherein the waveform parameters of the triangle wave can be specifically adjusted by adjusting R5-1 and C5.

[0106] In the specific implementation, the rectangular wave-spike wave conversion circuit adopts a differential circuit, which mainly includes an input end IN6, an operational amplifier OA6 and an output end OUT6, a capacitor C6-1, a circuit C6-2, a resistor R6-1, a resistor R6-2 and a resistor R6-3. Referring to Figure 8 , the input end IN5, the capacitor C6-1 and the resistor R6-1 are connected in series with the inverting input end of the operational amplifier OA6, and the non-inverting input end of the operational amplifier OA6 is connected to the ground through the resistor R6-2. The inverting input end of the operational amplifier OA6 is connected to the output end thereof through the capacitor C6-2, and the inverting input end of the operational amplifier OA6 is connected to the output end thereof through the resistor R6-3. The output end OUT6 is connected to the output end of the operational amplifier OA6. Among them, the resistor R6-1 is mainly used to prevent blocking, and the capacitor C6-2 connected in parallel on the feedback circuit can be used as a compensation circuit to prevent self-oscillation. The input voltage of the input signal of the input end IN6 is V IN6 , and the voltage V OUT6 of the output end OUT6 is:

[0107]

[0108] Therefore, when the input signal of the rectangular wave-spike wave conversion circuit is a rectangular wave, the output signal becomes a spike wave, wherein the waveform parameters of the triangle wave can be specifically adjusted by adjusting R6-3 and C6.

[0109] It is worth noting that the switch mechanism can be set so that the waveform conversion circuit 203 can input any one of the rectangular wave, the triangle wave and the spike wave, or simultaneously output multiple waveforms, and mix them with the test voltage signal in the adder 204 to simulate different types of surge events. The circuit structure of the surge generation module 2 in the embodiment is specifically shown in Figure 9 , the OUT4, the OUT and / or the OUT6 and the OUT1 or the OUT2 are respectively connected to the positive input end of the adder 204 through the input resistors R7-1, R7-2, R7-3 and R7-4, and the mixed output end OUT7 of the adder 204 outputs, that is, the test voltage signal after the load surge event is obtained.

[0110] It is worth noting that other waveform conversion circuits 203 can also be added to edit the pulse waveform output by the surge generation module 2 in the specific application process, such as a sine wave conversion circuit and a step wave conversion circuit, which will not be described herein.

[0111] The power source in the embodiment reduces different components and devices required in the surge test of the DC energy meter, reduces test cost and complexity, and makes the surge test more close to complex scenarios that may occur in the actual power system through multiple surge event simulation and custom waveform editing, thereby improving test accuracy. Meanwhile, the surge events under different time and situation can be dynamically adjusted in the application process to comprehensively evaluate the surge resistance performance of the tested device, adapt to various power system working conditions, thereby better meeting the performance evaluation requirements of the DC energy meter, and helping to improve the design and performance of the energy meter or other power system devices, and improve the reliability and stability thereof. According to a second aspect of the present application, a surge test method of a DC energy meter is also provided, comprising:

[0112] connecting the to-be-tested energy meter to the first output port of the power source to obtain a test voltage signal and a test current signal, and connecting a standard energy meter to the second output port of the power source to obtain a reference voltage signal and a reference current signal;

[0113] setting amplitudes, frequencies, surge event types and intensities of the test voltage signal, the test current signal, the reference voltage signal and the reference current signal;

[0114] starting the power source, starting the test based on the test voltage signal, the test current signal, the reference voltage signal and the reference current signal, and collecting response data of the to-be-tested energy meter and the standard energy meter during the test;

[0115] turning off the power source after the test is completed, taking the response data of the standard energy meter as a control group, and analyzing surge resistance performance of the to-be-tested energy meter.

[0116] Based on the power source for the surge test, the embodiment discloses a surge test method of a DC energy meter, which is tested by the power source in embodiment 1. Referring to Figure 10 , the surge test method in the embodiment specifically comprises the following steps:

[0117] Step 1, connect the to-be-tested electric energy meter to the first output port of the power source to obtain the test voltage signal and the test current signal, and connect the standard electric energy meter to the second output port of the power source to obtain the reference voltage signal and the reference current signal, specifically: connect the to-be-tested electric energy meter to the output port of the power source that outputs the test voltage signal and the test current signal, so that the to-be-tested electric energy meter can receive the test voltage signal and the test current signal from the power source as a test group, and connect the standard electric energy meter to the output port of the power source that outputs the reference voltage signal and the reference current signal, so that the standard electric energy meter can receive the reference voltage signal and the reference current signal from the power source as a control group;

[0118] Step 2, set the amplitude, frequency, and surge event type and intensity of the test voltage signal, the test current signal, the reference voltage signal, and the reference current signal, specifically: according to the test requirements, set the amplitude, frequency, and surge event type and intensity of the test voltage signal and the reference voltage signal, wherein a plurality of different intensity and / or different type of surge events can be edited and loaded on the test voltage signal, such as transient surge, transient surge, and continuous surge, etc.

[0119] Step 3, start the power source, start the test based on the test voltage signal, the test current signal, the reference voltage signal, and the reference current signal, and collect the response data of the to-be-tested electric energy meter and the standard electric energy meter during the test, specifically: start the power source to start the test, and collect the response data of the to-be-tested electric energy meter and the standard electric energy meter during the test, including the voltage waveform, amplitude, phase, etc. information, current waveform, amplitude, phase, etc. information, and timestamp information and abnormal data of the to-be-tested electric energy meter and the standard electric energy meter during the test, such as electric energy meter stop working, fault or alarm, etc.

[0120] Step 4, after the test is completed, turn off the power source, and analyze the surge resistance performance of the to-be-tested electric energy meter with the response data of the standard electric energy meter as the control group, in the specific implementation process, the surge resistance performance of the to-be-tested electric energy meter can be analyzed from the following angles:

[0121] Based on the response data of the to-be-tested electric energy meter and the standard electric energy meter, analyze the surge event response time of the to-be-tested electric energy meter;

[0122] Compare the current and voltage waveforms of the to-be-tested electric energy meter and the standard electric energy meter during the surge event;

[0123] Check whether the to-be-tested electric energy meter can maintain the accuracy of the response data during the surge event;

[0124] Evaluate whether the to-be-tested electric energy meter can quickly recover to the normal working state after the surge event ends;

[0125] to assess whether the under-test energy meter has an effective surge event detection and alarm system;

[0126] to assess the endurance and resistance of the under-test energy meter under surge events.

[0127] Those skilled in the art will appreciate that embodiments of the application can be supplied as methods, systems, or computer program products. Accordingly, the application can be embodied in the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the application can be embodied in the form of a computer program product on one or more computer readable storage media (including, but not limited to, disk memory, CD-ROMs, optical storage media, etc.) having computer usable program code embodied thereon. The aspects of the embodiments of the application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript, among others.

[0128] The application is described herein with reference to the flowchart and / or block diagrams of the methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each block of the flowchart and / or block diagrams, and combinations of blocks in the flowchart and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processing device or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart and / or block diagram block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 means for carrying out the function specified by the flowchart block or blocks.

[0129] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the flowchart and / or block diagram block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 means for carrying out the function specified by the flowchart block or blocks.

[0130] The computer program instructions can also be loaded into a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the flowchart and / or block diagram block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 means for carrying out the function specified by the flowchart block or blocks.

[0131] While the preferred embodiments of the application have been described, additional variations and modifications can be made to these embodiments by those skilled in the art once they have the benefit of the present disclosure without departing from the spirit and scope of the application. Accordingly, it is intended that such additions and modifications be included within the scope of the application. It is the following claims, including any amendments thereto, which define the scope of the application.

[0132] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A power source for surge testing, characterized by, The power source has two output ports, one of which outputs a test voltage signal with surge and its corresponding test current signal, and the other of which outputs a reference voltage signal without surge and its corresponding reference current signal; The frequency and amplitude of the test voltage signal in the non-surge band are the same as those of the reference voltage signal, and the frequency and amplitude of the test voltage signal in the surge band are different from those of the reference voltage signal, so as to simulate the voltage surge that may occur in the power system and take the reference voltage signal as a control group; The power source comprises: a signal generation module for generating and outputting two voltage signals with the same frequency and amplitude, and serving as the reference voltage signal and the test voltage signal respectively; a surge generation module for loading voltage surge events on the output path of the test voltage signal; a control system for ensuring that the signal generation module and the surge generation module generate synchronized signals, and dynamically adjusting the amplitude and frequency to achieve various test conditions; a current signal module for generating a test current signal corresponding to the test voltage signal and a reference current signal corresponding to the reference voltage signal; The signal generation module comprises: a signal generator for generating a signal waveform simulating a voltage signal; a brancher for dividing the analog voltage signal generated by the signal generator into two output paths and serving as the test voltage signal and the reference voltage signal respectively; The power source further comprises: an isolation circuit provided on the transmission path of the test voltage signal to the surge generation module, for isolating the brancher and the signal generator to avoid the influence of surge on the brancher and the signal generator.

2. The power source of claim 1, wherein The surge generation module comprises: a pulse generation circuit for generating a pulse signal with adjustable frequency and duty cycle; a variable gain amplification circuit electrically connected to the output end of the pulse generation circuit for adjusting the amplitude of the pulse signal; a waveform conversion circuit electrically connected to the output end of the variable gain amplification circuit for generating pulse signals corresponding to various types and intensities of voltage surge events; an adder electrically connected to the waveform conversion circuit and the signal generation module for loading the pulse signal on the test voltage signal to simulate voltage surge events.

3. The power source of claim 1, wherein, The power source further comprises: a first amplification circuit provided on the transmission path of the test voltage signal for adjustable gain amplification processing of the test voltage signal.

4. The power source of claim 1, wherein, The power source further comprises a second amplification circuit provided on the transmission path of the reference voltage signal for adjustable gain amplification processing of the reference voltage signal.

5. The power source of claim 1, wherein, The power source further comprises: a first filter circuit provided on the transmission path of the test voltage signal for filtering out high-frequency noise and stray signals in the test voltage signal.

6. The power source of claim 1, wherein, The power source further comprises a second filter circuit provided on the transmission path of the reference voltage signal for filtering out high-frequency noise and stray signals in the reference voltage signal.

7. The power source of claim 1, wherein the isolation circuit comprises an input terminal IN1, an operational amplifier OA1-1, a linear optocoupler, an operational amplifier OA1-2, and an output terminal OUT1. The linear optocoupler comprises pins 1-6, and is internally provided with an LED, a PD1, and a PD2, wherein the positive and negative poles of the LED are connected to pins 1 and 2 respectively, the positive and negative poles of the PD1 are connected to pins 4 and 3 respectively, and the positive and negative poles of the PD2 are connected to pins 5 and 6 respectively. In the signal input direction of the isolation circuit, the input terminal IN1 is connected to the inverting input terminal of the operational amplifier OA1-1, the non-inverting input terminal of the operational amplifier OA1-1 is grounded, the output terminal of the operational amplifier OA1-1 is connected to pin 1, and pins 1 and 2 are connected to a power supply, pin 3 is grounded, and pin 4 is connected to the inverting input terminal of the operational amplifier OA1-1. In the signal output direction of the isolation circuit, the inverting input terminal of the operational amplifier OA1-2 is connected to pin 6, the non-inverting input terminal and the ground terminal of the operational amplifier OA1-2 and pin 5 are all grounded, the power supply terminal of the operational amplifier OA1-2 is connected to a power supply, and the output terminal OUT1 is connected to the output terminal of the operational amplifier OA1-2.

8. The power source of claim 1, wherein the isolation circuit comprises an input terminal IN2, an operational amplifier OA2-1, a linear optocoupler, an operational amplifier OA2-2, and an output terminal OUT2. The linear optocoupler comprises pins 1-6, and is internally provided with an LED, a PD1, and a PD2, wherein the positive and negative poles of the LED are connected to pins 1 and 2 respectively, the positive and negative poles of the PD1 are connected to pins 4 and 3 respectively, and the positive and negative poles of the PD2 are connected to pins 5 and 6 respectively. In the signal input direction of the isolation circuit, the input terminal IN2 is connected to the inverting input terminal of the operational amplifier OA2-1, the output terminal of the operational amplifier OA2-1 is connected to pin 2, pin 1 is grounded, the non-inverting input terminal of the operational amplifier OA2-1 is grounded through a resistor R2-2, pin 4 is grounded, and pin 3 is connected to a power supply. In the signal output direction of the isolation circuit, pin 6 is connected to a power supply, pin 5 is connected to the non-inverting input terminal of the operational amplifier OA2-2, and is also grounded through a resistor R2-3, the power supply terminal of the operational amplifier OA2-2 is connected to a power supply, and the inverting input terminal and the output terminal of the operational amplifier OA2-2 are connected to the output terminal OUT2. comprising: connecting a to-be-tested electric energy meter to a first output port of the power source to obtain a test voltage signal and a test current signal, and connecting a standard electric energy meter to a second output port of the power source to obtain a reference voltage signal and a reference current signal; 9. A surge test method for a direct-current watt-hour meter based on the power source for surge test according to claim 1, characterized by, setting the amplitudes, frequencies, and surge event types and intensities of the test voltage signal, the test current signal, the reference voltage signal, and the reference current signal; starting the power source, starting the test based on the test voltage signal, the test current signal, the reference voltage signal, and the reference current signal, and collecting response data of the to-be-tested electric energy meter and the standard electric energy meter during the test; after the test is completed, shutting down the power source, and taking the response data of the standard electric energy meter as a control group to analyze the surge resistance performance of the to-be-tested electric energy meter. ​ ​ 10. The method of claim 9, wherein, With the response data of the standard electric energy meter as a control group, the anti-surge performance of the to-be-tested electric energy meter is analyzed, including: comparing the current and voltage waveforms of the to-be-tested electric energy meter and the standard electric energy meter during the surge event; and / or checking whether the to-be-tested electric energy meter can maintain the accuracy of the response data during the surge event; and / or evaluating whether the to-be-tested electric energy meter can quickly recover to the normal working state after the end of the surge event; and / or evaluating whether the to-be-tested electric energy meter has an effective surge event detection and alarm system; and / or evaluating the durability and tolerance of the to-be-tested electric energy meter under the surge event.

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