Method, system and equipment for identifying resistive load of electric energy meter without air conditioner

Abstract

The invention relates to an electric energy meter resistive load identification method for eliminating an air conditioner, and the method comprises the steps: determining whether a load is suspected of being an air conditioner or not through employing an air conditioner elimination algorithm after the load is determined to be a resistive load, and the air conditioner elimination algorithm specifically comprises the steps: recording a power value when the load is connected after the resistive load is identified, and a power value per second within the next N seconds; calculating a root mean square of a power value within N seconds after the load is accessed; the root-mean-square is compared with a set threshold value, if the root-mean-square exceeds the threshold value, it is judged that the load is suspected to be an air conditioner, and tripping is not conducted; otherwise, judging that the load is not an air conditioner, and tripping. Compared with the prior art, the method has the advantages of being low in cost, capable of accurately recognizing the air conditioner and suitable for large-area upgrading of the college dormitory electric control system, and therefore the problem that the college dormitory electric control system trips by mistake due to use of the air conditioner is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electricity management, and in particular to a method, system and device for identifying resistive loads of an electric energy meter excluding air conditioners. Background Art

[0002] Electrical safety in schools has always been a top priority for university logistics management. In recent years, many schools, especially universities, have installed air conditioners in dormitories and classrooms to provide students with a comfortable working and learning environment. Once connected to the power lines, air conditioners share the same circuit with lighting and electrical outlets, increasing the overall load on the circuit. Air conditioners are often mistakenly identified as illegal electrical appliances, causing dormitory circuit breakers to trip.

[0003] Traditional malicious load identification algorithms, based on the difference in data from relevant electrical parameters (current, power, power factor, harmonics, etc.) after the load is connected, can relatively accurately identify resistive loads that primarily generate heat, and immediately trip the circuit breaker when the identification criteria are met. However, air conditioners (especially those operating in winter) in the circuit can be easily misidentified as resistive loads.

[0004] The current mainstream air conditioning load identification algorithm requires capturing a large amount of data model features for analysis and combining it with a cloud-based load library to achieve accurate air conditioning identification. It has high requirements for software and hardware costs and is not universal in traditional dormitory electrical control systems.

[0005] Load modeling-based identification methods build mathematical models of legitimate loads (such as resistance, inductance, and capacitance parameters) and identify anomalies by comparing measured data with the model. This method is highly accurate for identifying known load types, but requires pre-established models, has weak generalization capabilities, and is difficult to handle for unknown, illegal loads, making it unsuitable for dormitory electrical control systems.

[0006] After searching, Chinese invention patent application publication number CN108573288A discloses a resistive load identification and learning method based on an electric energy meter. The method provides an on-site identification system embedded in a smart meter. The on-site identification system obtains the operating parameters of the newly added load, uses an on-site identification algorithm model to identify the newly added load in real time, and controls the load based on the identification results. The method also provides a host computer learning system compatible with the smart meter. The host computer learning system uses a remote identification algorithm model to learn the operating parameters of the newly added load uploaded by the smart meter, obtains the identification parameters corresponding to the newly added load, and transmits and stores them to the smart meter for the smart meter to quickly identify subsequent newly added loads. Specifically, if the active power change value, power factor change value, and apparent power factor change value of the newly added load are all greater than the corresponding threshold value, the resistive load is judged to be a malicious load; otherwise, it is a non-malicious load. This existing patent application is not suitable for judging normal high-power loads (such as air conditioners) and may misjudge air conditioners.

[0007] How to realize the resistive load identification of electricity meters by eliminating air conditioners at low cost has become a technical problem that needs to be solved. Summary of the Invention

[0008] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a method, system and device for identifying the resistive load of an electric energy meter that eliminates air conditioners.

[0009] The purpose of the present invention can be achieved by the following technical solutions:

[0010] According to one aspect of the present invention, a method for identifying resistive loads of an electric energy meter by eliminating air conditioners is provided, the method comprising the following steps:

[0011] S1, determine whether the load is a resistive load, if yes, execute S2; otherwise, end;

[0012] S2, use the air conditioning rejection algorithm to further determine whether the load is suspected to be an air conditioner. If yes, then end; otherwise, execute S3;

[0013] S3, set negative control trip, end;

[0014] The S2 process includes:

[0015] 101, after the resistive load is identified, the power value when the load is connected and the power value per second in the next N seconds are recorded;

[0016] 102, calculate the root mean square of the power value within N seconds after the load is connected;

[0017] 103, compare the RMS value with the set threshold value. If the RMS value exceeds the threshold value, the load is judged to be an air conditioner and no trip is performed; otherwise, the load is judged to be not an air conditioner and a trip is performed.

[0018] Preferably, after the resistive load is identified, the power value P0 when the load is connected and the power value per second in the next N seconds are recorded, which are P1, P2, P3, P4, ..., P N , then the calculation of the root mean square power value dat within N seconds after the load is connected is:

[0019]

[0020] Where N+1 is the total power value after the load is connected; P i is the i-th power value.

[0021] Preferably, the N seconds is 5 seconds.

[0022] Preferably, the set threshold is 100.

[0023] According to another aspect of the present invention, a resistive load identification system for an electric energy meter for rejecting air conditioners is provided. The system includes a resistive load judgment module and a tripping module. The system also includes an air conditioner rejection module, and the air conditioner rejection module is respectively connected to the resistive load judgment module and the tripping module.

[0024] Preferably, after the load is connected, the air-conditioning rejection module uses an air-conditioning rejection algorithm to determine whether the load is suspected to be an air-conditioning. If it is suspected to be an air-conditioning, the operation is terminated. Otherwise, if the load is determined to be a resistive load, that is, the load is not an air-conditioning, the circuit breaker is tripped.

[0025] More preferably, the air conditioner elimination algorithm includes:

[0026] After the resistive load is identified, the power value when the load is connected and the power value per second for the next N seconds are recorded;

[0027] Calculate the RMS power value within N seconds after the load is connected;

[0028] Compare the RMS value with the set threshold. If the RMS value exceeds the threshold, the load is suspected to be an air conditioner and no trip is performed. Otherwise, the load is determined not to be an air conditioner and a trip is performed.

[0029] Preferably, the resistive load judgment module is used to analyze the characteristics of common loads allowed and loads not allowed in university dormitories, and judge whether they are resistive loads.

[0030] According to another aspect of the present invention, an electronic device is provided, comprising a memory and a processor, wherein a computer program is stored in the memory, and the method described above is implemented when the processor executes the program.

[0031] According to a third aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored, and when the program is executed by a processor, the method described above is implemented.

[0032] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored, and when the program is executed by a processor, the method described above is implemented.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1) The method of the present invention is simple and practical, does not require additional hardware and cloud servers, and does not require pre-established models. It is low-cost and can accurately identify whether the load is an air conditioner by adding an algorithm to the electricity meter to identify whether the load is suspected to be an air conditioner. This solves the problem of false tripping of the electrical control system in university dormitories due to the use of air conditioners.

[0035] 2) The method of the present invention has low transformation cost, is suitable for large-scale upgrades of dormitory electrical control systems, and has strong versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a flow chart of the traditional malicious payload identification algorithm;

[0037] Figure 2 Schematic diagram of the resistive load identification method of the present invention;

[0038] Figure 3 Schematic diagram of the flow of the air conditioning elimination algorithm in the present invention. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0040] Example 1

[0041] This embodiment provides a method for identifying resistive loads in electricity meters to eliminate air conditioners. This method aims to address the problem of false tripping of dormitory electrical control systems due to air conditioner use, while providing a low-cost retrofit solution. By improving upon a traditional algorithm for identifying harmful loads, an air conditioner elimination algorithm is proposed to prevent false tripping when the air conditioner is turned on.

[0042] The traditional malicious load identification algorithm is based on the difference in data of relevant electrical parameters (current, power, power factor, harmonics, etc.) after the load is connected to determine whether the load is a violation type. It can more accurately identify resistive loads that are mainly heat-generating and trip immediately when the identification conditions are met. Its flow chart is as follows Figure 1 As shown in the figure, threshold ranges for key electrical parameters (such as current, power, and power factor) are set. When the measured value exceeds the threshold, it is determined to be a malicious load. This algorithm is simple to implement and has fast calculation speed, making it suitable for detecting obvious anomalies (such as short circuits and overloads). However, it cannot distinguish between normal high-power loads (such as air conditioners) and illegal loads. Therefore, it is easy to misjudge as a resistive load in the electrical control system of university dormitories, especially during the winter when the air conditioner is in use for heating.

[0043] Harmonic analysis-based identification methods often generate specific harmonics (e.g., odd harmonics) for malicious loads (e.g., rectifiers and LED lights). These are identified by analyzing the harmonic distortion (THD) of the current or specific harmonic components (e.g., third and fifth harmonics). While this method is effective for loads containing nonlinear components (e.g., chargers and inverters), it requires high-precision harmonic measurement equipment, which is costly and unsuitable for large-scale upgrades of dormitory electrical control systems.

[0044] Therefore, this application aims to realize the identification of air-conditioning loads in dormitory electrical control systems at low cost and with strong versatility, thereby eliminating the judgment that the circuit trips due to the air-conditioning being turned on. This method is based on the analysis of the characteristics of common loads allowed to be used in university dormitories (lamps, routers, computers, notebooks, etc.) and loads not allowed to be used (kettles, rice cookers, electric blankets, etc.), and the addition of an air-conditioning elimination algorithm. The purpose of the air-conditioning elimination algorithm is not to accurately identify the different operating states of air conditioners of various brands for non-invasive load energy consumption research, but to address the problem that air conditioners are identified as resistive loads by traditional malicious load identification algorithms.

[0045] The electric energy meter resistive load identification method of the present application adds an air conditioner rejection algorithm based on the traditional malicious load identification algorithm to determine whether the load is suspected to be an air conditioner. The process is as follows: Figure 2 Shown, including:

[0046] S1, determine whether it is a resistive load, if yes, execute S2; otherwise end;

[0047] S2, further determine whether the load is suspected to be an air conditioner, if yes, then end; otherwise, execute S3;

[0048] S3, set negative control trip, end.

[0049] The process of the air conditioning elimination algorithm is as follows Figure 3 As shown, the following steps are included:

[0050] 101, after identifying the resistive load, record the power value P0 when the load is connected, and the power value per second in the next N seconds, which are P1, P2, P3, P4, ..., P N ;

[0051] 102, calculate the power value (P0~P N )'s root mean square dat;

[0052]

[0053] Where N+1 is the total power value after the load is connected; P i is the i-th power value.

[0054] 103, compare the RMS dat with the set threshold. If the RMS exceeds the threshold, it is determined that the load is suspected to be an air conditioner and no trip is performed; otherwise, it is determined to be a resistive load, that is, the load is not an air conditioner and a trip is performed.

[0055] The method is simple in design and requires no additional hardware or cloud servers, enabling low-cost identification of resistive loads that exclude air conditioners. It eliminates the need for building a large data model library for precise characteristic analysis, thus preventing tripping caused by air conditioner use. Its simplicity, practicality, and low cost facilitate large-scale upgrades of university dormitory power management systems to address the issue of air conditioner tripping, and its versatility is highly applicable.

[0056] Example 2

[0057] This embodiment involves the verification of a method for identifying resistive loads of an electric energy meter excluding air conditioners. The threshold is set to 100, and different permutations and combinations of common dormitory loads are performed. Tests are performed under different combinations. The test results are shown in Table 1.

[0058] Table 1

[0059] Test Load RMS Setting thresholds Test results Light + router + laptop + air conditioner (start) 523 100 No tripping Light + router + laptop + air conditioner (start) 260 100 No tripping Light + router + laptop + air conditioner (running) + kettle 28 100 Trip Light + router + laptop + air conditioner (running) + kettle 47 100 Trip Lamp + router + laptop + kettle 34 100 Trip Lamp + router + laptop + kettle 44 100 Trip

[0060] As shown in Table 1, when the dormitory allows the use of a combination of loads (lights, routers, laptops) plus an air conditioner, if the RMS power within 5 seconds after the air conditioner is turned on is greater than the set threshold of 100, the load is suspected to be the air conditioner and the circuit breaker does not trip. When the air conditioner is turned on and the RMS power within 5 seconds after adding a kettle is less than the set threshold, the load is judged not to be the air conditioner and the circuit breaker trips. When the dormitory allows the use of a combination of loads (lights, routers, laptops) plus a kettle, if the RMS power within 5 seconds after the kettle is turned on is less than the set threshold, the load is judged not to be the air conditioner and the circuit breaker trips.

[0061] Example 3

[0062] This embodiment relates to a resistive load identification system for an electric energy meter for rejecting air conditioners. The system includes a resistive load judgment module, an air conditioner rejection module, and a tripping module connected in sequence.

[0063] Resistive load determination module: Analyzes the characteristics of common loads allowed in university dormitories (lamps, routers, computers, laptops, etc.) and unallowed loads (kettles, rice cookers, electric blankets, etc.), and determines whether they are resistive loads;

[0064] Air conditioning rejection module: After the load is connected, the air conditioning rejection algorithm is used to determine whether the load is suspected to be an air conditioner. If it is suspected to be an air conditioner, the operation is terminated. Otherwise, if the load is determined to be a resistive load, that is, the load is not an air conditioner, the circuit breaker is tripped.

[0065] Example 4

[0066] The electronic device of the present invention includes a central processing unit (CPU), which can perform various appropriate actions and processes according to computer program instructions stored in a read-only memory (ROM) or loaded from a storage unit into a random access memory (RAM). In the RAM, various programs and data required for device operation can also be stored. The CPU, ROM, and RAM are connected to each other via a bus. An input / output (I / O) interface is also connected to the bus.

[0067] Many components in a device are connected to the I / O interface, including: input units, such as a keyboard and mouse; output units, such as various types of displays and speakers; storage units, such as magnetic disks and optical disks; and communication units, such as network cards, modems, and wireless communication transceivers. The communication unit allows the device to exchange information / data with other devices via computer networks such as the Internet and / or various telecommunication networks.

[0068] The processing unit performs the various methods and processes described above. For example, in some embodiments, the method can be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit. In some embodiments, part or all of the computer program can be loaded and / or installed on the device via a ROM and / or a communication unit. When the computer program is loaded into RAM and executed by the CPU, one or more steps of the method described above can be performed. Alternatively, in other embodiments, the CPU can be configured to execute the method in any other appropriate manner (e.g., by means of firmware).

[0069] The functions described above herein may be performed, at least in part, by one or more hardware logic components. For example, and without limitation, exemplary types of hardware logic components that may be used include: field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chip (SOCs), complex programmable logic devices (CPLDs), and the like.

[0070] The program code for implementing the method of the present invention can be written in any combination of one or more programming languages. Such program code can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device so that when the program code is executed by the processor or controller, the functions / operations specified in the flow chart and / or block diagram are implemented. The program code can be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0071] In the context of the present invention, machine-readable medium can be a tangible medium that can contain or store a program for use with an instruction execution system, device or equipment or used in combination with an instruction execution system, device or equipment. Machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. Machine-readable medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. More specific examples of machine-readable storage media can include electrical connections based on one or more lines, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0072] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A method for identifying resistive loads of electric energy meters excluding air conditioners, characterized in that: The method comprises the following steps: S1, determine whether the load is a resistive load, if yes, execute S2; otherwise, end; S2, use the air conditioning rejection algorithm to further determine whether the load is suspected to be an air conditioner. If yes, then end; otherwise, execute S3; S3, set negative control trip, end; The S2 process includes: 101, after the resistive load is identified, the power value when the load is connected and the power value per second in the next N seconds are recorded; 102, calculate the root mean square of the power value within N seconds after the load is connected; 103, compare the RMS value with the set threshold value. If the RMS value exceeds the threshold value, the load is judged to be an air conditioner and no trip is performed; otherwise, the load is judged to be not an air conditioner and a trip is performed.

2. A method for identifying resistive loads of electric energy meters excluding air conditioners according to claim 1, characterized in that: After the resistive load is identified, the power value P0 when the load is connected and the power value per second in the next N seconds are recorded as P1, P2, P3, P4, ..., P N , then the calculation of the root mean square power value dat within N seconds after the load is connected is: Where N+1 is the total power value after the load is connected; P i is the i-th power value.

3. The method for identifying resistive loads of electric energy meters by eliminating air conditioners according to claim 1, characterized in that: The N seconds is 5 seconds.

4. The method for identifying resistive loads of electric energy meters by eliminating air conditioners according to claim 1, characterized in that: The set threshold is 100.

5. A system for executing the method for identifying resistive loads of electric energy meters for excluding air conditioners according to any one of claims 1 to 4, the system comprising a resistive load judgment module and a tripping module, characterized in that: The system comprises an air-conditioning rejection module, which is respectively connected to the resistive load judgment module and the tripping module.

6. A method for identifying resistive loads of electric energy meters excluding air conditioners according to claim 5, characterized in that: After the load is connected, the air-conditioning rejection module uses the air-conditioning rejection algorithm to determine whether the load is suspected to be an air-conditioning. If it is suspected to be an air-conditioning, the operation ends. Otherwise, if the load is determined to be a resistive load, that is, the load is not an air-conditioning, the circuit breaker is tripped.

7. A method for identifying resistive loads of electric energy meters excluding air conditioners according to claim 6, characterized in that: The air conditioner rejection algorithm includes: After the resistive load is identified, the power value when the load is connected and the power value per second for the next N seconds are recorded; Calculate the RMS power value within N seconds after the load is connected; Compare the RMS value with the set threshold. If the RMS value exceeds the threshold, the load is suspected to be an air conditioner and no trip is performed. Otherwise, the load is determined not to be an air conditioner and a trip is performed.

8. The method for identifying resistive loads of electric energy meters excluding air conditioners according to claim 5, characterized in that: The resistive load judgment module is used to analyze the characteristics of common loads allowed and loads not allowed in university dormitories, and to judge whether they are resistive loads.

9. An electronic device comprising a memory and a processor, wherein a computer program is stored in the memory, wherein: When the processor executes the program, the method according to any one of claims 1 to 4 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 4 is implemented.

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