Abstract
In order to study the optimization of information acquisition security of broadband carrier communication and solve the problem of low baud rate of data acquisition in traditional communication operation data acquisition systems, this article reconstructs the required arrangement of communication operation data signals in the acquisition path by taking broadband carrier communication in the station area as an example through the linear equation method of genetic algorithm. The baud rate of the designed acquisition system is significantly higher than that of the control group, and the acquisition accuracy is 100% by using phase shift key modulation and high carrier frequency. It can solve the problem of low baud rate of data acquisition in traditional communication operation data acquisition systems and improve the security of information acquisition. The security (loss, anti-interference) of broadband carrier communication information collection based on the improved legacy algorithm is better than that of the traditional genetic algorithm, indicating that the security of broadband carrier communication information collection based on the improved legacy algorithm does not increase with the number of iterations and decrease.
1 Introduction
Low-voltage power line is not specially used to transmit communication data, its topology and physical characteristics are different from traditional communication transmission media, such as twisted pair, coaxial cable, and optical fiber. Power line communication transmits high-speed data information on the channel loaded with power frequency power signal, so it has the characteristics of harsh working environment, serious noise interference, and large time-varying. At the same time, the signal is prone to reflection, standing wave and resonance, which makes the attenuation characteristics of the signal extremely complex, resulting in a strong frequency selectivity of the power line communication channel. At present, broadband carrier communication has been widely used in station area smart meters. It has the characteristics of strong anti-crosstalk ability and real-time monitoring. However, the acquisition of a large number of broadband carrier communication information will produce redundant information and useless information, which will seriously reduce the efficiency of information acquisition and improve the error rate of information acquisition [1]. Taking the broadband carrier communication in the station area as an example, this article analyzes the optimization of information acquisition security by linear equation and genetic algorithm, so as to improve the information security level of meter reading and intelligent station area. Communication operation data refers to the data that needs to be transmitted in the communication process. Generally, it contains a lot of effective information [2]. A modulation technique is a process of converting a signal produced by a source into a form suitable for wireless transmission. After quantizing the analog signal samples, it modulates the optical carrier on and off with a binary digital signal “1” or “0,” and performs pulse coding (PCM). The advantage of digital modulation is that it has strong anti-interference ability, and the influence of noise and dispersion does not accumulate during relay, so long-distance transmission can be realized. Therefore, communication operation data acquisition is an effective way to obtain information. Based on this, the communication operation data acquisition system mainly realizes the unified acquisition of communication operation data through communication operation data processing. However, the traditional communication operation data acquisition system often has the defect of low acquisition baud rate in practical application. The main reason for this phenomenon is that the processing of communication operation data is not efficient enough, and it is difficult to meet the efficient acquisition of communication operation data with a large base and different types. The optimization design of the communication operation data acquisition system is of practical significance and can provide support for the development of communication operation data acquisition [3,4]. It can be seen that the previous communication operation data acquisition system has shortcomings and needs to be improved. As a composite function, the linear equation algorithm can obtain the conversion formula by setting intermediate variables, so as to improve the processing speed of communication operation data. In the linear equation algorithm, the derivative (FX) of the auxiliary function is known. In this case, the linear equation algorithm can transform the complex problem into a simple linear problem, then calculate, and solve it. After the transformation is completed, the acquisition success rate of the power consumption information acquisition system is guaranteed to reach more than 98%, realizing the functions of real-time acquisition, timing acquisition, and meter fee control of low-voltage power users, and further realizing the functions of comprehensive monitoring, resource management, alarm management and performance management of low-voltage power users, so as to realize the unified and comprehensive management of distribution and power communication network [5,6]. At present, broadband carrier communication is widely used in smart meters in the station area, which has the characteristics of strong anti-crosstalk ability and real-time monitoring. However, the collection of a large number of broadband carrier communication information will generate redundant information and useless information, which will seriously reduce the efficiency of information collection and improve the error rate of information collection. Taking broadband carrier communication in station areas as an example, this article analyzes the optimization of information collection security by genetic algorithm and promotes the improvement of information security level of meter reading and intelligent station area.
2 Literature review
It is necessary to further improve the energy consumption information collection system to meet the urgent needs of the company to meet the urgent needs of the company at all levels and disciplines. information [7]. Deya proposed comprehensive coverage of power users, comprehensive collection of power information, comprehensive prepayment management, and opinions on local communication networks, including narrowband power line carrier, broadband power line carrier, micro-power wireless communication, RS485 communication technology, low-voltage Centralized meter reading, and other construction schemes [8]. State Grid Corporation of China has installed a total of 180 million smart meters, with a total of 190 million users, a collection coverage rate of 56%, and an automatic meter reading accounting rate of over 97%. Ni et al. expect to have more than 40 million dual-function (detecting gas and electricity) smart meters [9]. Katz and Fridman also hope to encourage energy-efficient transitions, and detailed electricity consumption information will be helpful. Many European power companies want to use electricity meters to improve their relationship with customers. In Europe, as in the United States, few people have a favorable opinion of power companies [10]. For example, Li et al. wrote in the report, “The Danish power utility Sea-NVE is very concerned about the relationship with customers. They even train installers how to talk to customers in their homes. As a result, the power utility has experienced a substantial complaint rate Reduced, now users save an average of 16% on their electricity bills.” Although Europe is still reeling from the economic crisis, many countries have adopted measures to measure it [11]. Earlier this year, Fournaris and others announced plans to deploy 35 million smart meters, while the UK set an even bigger target for smart meters. They announced a smart grid communications contract worth $7.5 billion. As of February 2015, more than 50 million smart meters have been deployed in the United States, of which Southern California Edison (SCE) is the most typical, with about 5 million smart meters serving its power supply area [12]. With the help of smart meters, SCE has fully realized the billing function and is also exploring the next development strategy of smart meters. Batra et al. stated that SCE plans to use the rich data resources of smart meters for a wider range of purposes, and more utilities are brainstorming to unlock the great value of data applications! In addition, based on the interconnection model established by utility companies, engineers are also investigating the potential application of connection automation from the home side to the transformer side, which is currently highly manual [13]. SCE also hopes to use smart meter data for phase identification and data analysis to ensure a three-phase balance of the load.
Japan revised the basic energy plan in June 2010, and the policy is to “continue to fully consider the investment effect and allow all users who apply to install smart energy meters as soon as possible from 2020.” Ten large power companies are popularizing the next-generation power meter “smartmeter” with a communication function, which is expected to be set up in all households in the district by the end of 2024 [14]. According to the requirements of the government, the popularization progress will be accelerated, and companies will work overtime to meet the standard. It is estimated that around 2020, all households in Japan can use energy-saving and convenient smart meters. The utility model has the functions of fast communication between electric power companies and smart electricity meters. Every 30 minutes, the power company can grasp the power consumption of each family, and the power company can also make a variety of cost menus. In terms of users, users can save electricity according to the power-saving suggestions of the power company, and the electricity charge can also be reduced. To this end, the government rushed to introduce new meters to power companies [15,16]. The system structure diagram is shown in Figure 1.
Architecture of power consumption information acquisition system.
3 Research methods
3.1 Security description of broadband carrier communication information acquisition
Description of security problems of broadband carrier communication information acquisition in the station area in order to better analyze the problems of broadband carrier communication information acquisition is necessary to mathematically describe the above-mentioned indicators and problems. The specific contents are as follows:
It is assumed that m in the broadband carrier communication information acquisition in the station area is the information acquisition index set, and different information acquisition indexes correspond to different broadband carrier communication items. Moreover, the ID of the electricity meter in which each information acquisition index is located is different from that of other equipment in the station area (low-voltage circuit breaker and measurement and control device).
If n is the broadband carrier communication item, i is the meter reading item number, j is the meter ID, k is a low-voltage circuit breaker, l is the monitoring device, and m is the intelligent terminal; the information acquisition item can be described as Ni, j, k, l, and m (i, j, k, l, m = 1,2,., n, n is a natural number).
Taking security as a unit, customers with similar items, acquisition difficulties, and delay requirements in the same station area are classified into the security of broadband carrier communication information acquisition in one station area.
The electricity meter and other equipment IDs of any broadband carrier communication item in the broadband carrier communication information acquisition of the station area are arranged by the information acquisition center of the station area. Due to the constraints of security and accuracy, the electricity meter and other equipment IDs of the station area are required to follow a certain order.
Broadband carrier communication information collection in the station area of any broadband carrier communication item has time and security requirements, and the information collection time and security of the same broadband carrier communication item are the same.
The interference is included in the acquisition security in the broadband carrier communication information acquisition in the station area, and the calculation formula is shown in formula (1):
(1)where P is the anti-interference capability; x is the degree of information encryption; y is the communication time; z is the communication distance; and ζ is the interference adjustment factor.
It is assumed that all broadband carrier communication items n are set before the acquisition of broadband carrier communication information in the station area.
3.2 Linear equation algorithm
The core of the linear equation algorithm is matrix decomposition. Through matrix decomposition, the complex calculation method of a large matrix is simplified, and then, the solution speed is improved. In this article, the curve is divided into several intervals by using the linear equation algorithm. The integral function in the interval is approximated by the linear interpolation formula, and then, the calculus function is approximated (Naseem et al., 2021). Assuming that the equation solution of node m (x, y) exists in the range of [0, t], the curve isometric subdivision is made based on the linear equation algorithm, and formula (2) can be obtained.
where n refers to the number of approximate intervals of linear interpolation formula, which is a real number. After the equidistant partition of the curve based on the linear equation algorithm through formula (2), the approximate value of the solution of the equation at the calculus node M (x, y) is calculated. Based on the linear equation algorithm, the approximate value of calculus is linearly approximated, and the problem of calculus is transformed into separable variables. In the process of linear approximation of calculus approximation based on linear equation algorithm, the problem of implicit general solution must be considered [17,18,19]. At this time, the approximate value of calculus needs to be set to any complex number or any reply number by Euler’s common answer formula. Based on this, Eq. (3) can be obtained
The above refers to the definition domain of the calculus function. It refers to the separable variables existing in the implicit general solution of the calculus function. It refers to any constant of the tangent slope of node M(x, y) in the curve. Realize the linear approximation of calculus approximation based on linear equation algorithm, and solve the implicit general solution problem in calculus solution. Through the above-mentioned formula, the application process of the linear equation algorithm can be clarified. In this article, the linear equation algorithm is applied to the design of a communication operation data acquisition system. The specific design content of the communication operation data acquisition system based on a linear equation algorithm is described below [20,21].
3.3 Genetic algorithm design
To calculate the information acquisition security of broadband carrier communication in the station area with an improved genetic algorithm, we should first analyze the relationship between electric meters and construct the sequence of broadband carrier communication items. Assuming that each user has o broadband carrier communication items and r information acquisition indicators, the code of each broadband carrier communication item is Ni, j, k, l, m, and the mathematical description is:
Set the number of initial broadband carrier communication items popsize, external interference Pc, internal interference Pm, broadband carrier communication item codes Ni, j, k, l, m, as well as the most accurate transmission scheme Sch and the scheme with the shortest transmission time.
Judge the termination conditions of genetic algorithm iteration, and terminate the calculation if it meets the requirements.
Set the probability of information loss and interference according to metropolis acceptance criteria, adjust the information acquisition scheme, and calculate the probability of interference and delay again. Find the best information collection scheme according to metropolis acceptance criteria.
Store the accurate transmission scheme in Sch and the shortest transmission time scheme in total respectively.
Go to step 3) and repeat the calculation.
Output the optimal solution and end the operation.
4 Result analysis
4.1 Experimental preparation
After adjusting the communication time and signal strength of about 100yte segments, the specific time-consuming data of 100yte segments and typical operation areas are selected and analyzed. First, the system based on the linear equation algorithm is designed to collect the communication operation data, the acquisition port is connected to the computer, and the data acquisition baud rate is measured by MATALB software, which is recorded as the experimental group. Then, the traditional system is used to collect the communication operation data, also the acquisition port is connected to the computer, and the data acquisition baud rate are measured through MATALB software. The higher the baud rate of data acquisition, the higher the efficiency of data acquisition and the higher the system performance for communication operation in the same period. In this example analysis, the number of target communication operation data collection is 2,000, the set area range is (0,10,000), and the experimental data are recorded [22,23].
4.2 Analysis of experimental results
The experimental results are sorted out, as shown in Table 1.
Baud rate comparison of data acquisition
| Number of test | Area | Experimental group data acquisition Baud rate (Bt) | Control group data acquisition Baud rate (Bt) | Collect the number |
|---|---|---|---|---|
| 1 | (0, 10,000) | 0.18 | 0.02 | 2,000 |
| 2 | (0, 10,000) | 0.19 | 0.04 | 2,000 |
| 3 | (0, 10,000) | 0.19 | 0.04 | 2,000 |
| 4 | (0, 10,000) | 0.17 | 0.01 | 2,000 |
| 5 | (0, 10,000) | 0.19 | 0.04 | 2,000 |
| 6 | (0, 10,000) | 0.17 | 0.03 | 2,000 |
It can be seen from Table 1 that the acquisition baud rate of the acquisition system designed in this article is significantly higher than that of the control group. In the same area, the data acquisition efficiency for communication operations is higher, which has practical application value and is worthy of being vigorously promoted [24].
4.3 Improved genetic algorithm results
In order to investigate the optimization degree of improved genetic algorithm on the security of broadband carrier communication information acquisition in the station area, Matlab calculation is carried out. Set the accuracy parameters such as information acquisition accuracy, loss and interference, and analyze the corresponding algorithm. The results are shown in Table 2.
Results of improved genetic algorithm [Popsize (n = 50)]
| Judgment item | P1 | Number of iterations T 0 | Restrictionsa | Improved genetic algorithm |
|---|---|---|---|---|
| Number of successful information collection | 0.1 | 150 | 2 | 0.97 |
| Reading delay | 0.1 | 150 | 3 | 0.001 |
| Number of successful calls of master station | 0.1 | 150 | 2 | 0.001 |
| Communication distance | 0.1 | 150 | 2 | 1 km |
| Station area line loss | 0.1 | 150 | 3 | 0.003 |
| Table number reporting | 0.1 | 150 | 3 | 0.01 |
| Networking time | 0.1 | 150 | 2 | 0.01 |
| Network access time | 0.1 | 150 | 3 | 0.01 |
| Crosstalk coefficient | 0.1 | 150 | 3 | 0.01 |
| Relay level | 0.2 | 150 | 2 | 15级 |
The security (loss and anti-interference) of the station-wide-band carrier communication information acquisition based on the improved heritage algorithm is better than the traditional genetic algorithm, which shows that the security of the station-wide-band carrier communication information acquisition based on the improved heritage algorithm does not decrease with the increase of the number of iterations.
4.4 Application of power carrier technology in power consumption information acquisition laboratory simulation test
Representative companies No. 1 and No. 2 were selected in this experiment. The main technical indicators of these two companies are shown in Table 3. Test method: implement + 50 dB attenuation test and test without attenuation and interference. The previous test methods are the same, mainly through 30 electric energy meters and a concentrator to establish a carrier communication platform, and implement meter reading through the system. Test results are listed Tables 4 and 5. According to the earlier test results, the PSK modulation mode and the means of higher carrier frequency can achieve relatively ideal performance through the effect.
Main technical indicators of No. 1 and No. 2 companies
| Manufacturer | Carrier communication technology | Center frequency (kHz) |
|---|---|---|
| 1 | FSK | 421 |
| 2 | PSK | 120 |
Copy success of No. 1 and No. 2 companies
| Manufacturer | Linear way | Ground cable | Mixed cabling mode | Overhead line |
|---|---|---|---|---|
| 1 | 1 | 30 | 30 | 30 |
| 2 | 30 | 30 | 30 | |
| 2 | 1 | 30 | 30 | 0 |
| 2 | 30 | 30 | 0 |
Reading accuracy of No. 1 and No. 2 companies
| Manufacturer | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% |
| 2 | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% | 100% |
Two-way real-time interactive query of abnormal power consumption records through smart meters, providing reliable real-time data for fault analysis, finding equipment or systems with excessive energy consumption or unreasonable operation, and giving suggestions for improving energy-saving operation management, and formulating more accurate energy-saving operation management: load forecasting, guiding energy optimization scheduling, and realizing energy allocation optimization and three-phase power balance.
The fitness function of broadband carrier information security in the station area is taken as 0.001 to meet the accuracy requirements of the intelligent centralized reading system and the low-voltage visualization system. The degree of agreement between the theoretical value of the broadband carrier communication term and the actual value is the result of the fitness function. Therefore, a penalty threshold should be set between the theoretical value and the actual value of the broadband carrier communication item.
5 Discuss
The most basic requirements of power customers for power supply enterprises are: to provide reliable and stable power supply and high-quality service levels. It is not only expected that the power supply equipment will not harm the human body, nor pollute the environment. In addition, we hope that the personal safety and property safety of customers can be guaranteed in the process of power supply. Therefore, the stability and security of power supply quality are the most important factors affecting customer satisfaction. At present, the narrow-band carrier wave and micro-power wireless collection scheme adopted in the electricity information collection system have a low success rate of charge control, which makes the stability and safety of the power supply not guaranteed. The resulting user complaints directly reduce the image of the power supply company in the eyes of the majority of power customers. Broadband carrier communication technology provides two-way, real-time, high-speed communication based on power lines. It effectively solves the problem of low real-time communication in other technical solutions, improves the timeliness of reading customer electricity consumption information and the accuracy of meter reading and calculation, and also greatly improves the sensitivity of control instruction execution.
6 Conclusion
As an important part of power information system, power carrier technology plays an important role in realizing system communication. On this basis, the necessity of the optimal design is proved by proving the applicability of the acquisition system in practical applications. Therefore, we have reason to believe that the design of this article can solve the disadvantage of low efficiency in data collection of traditional communication operations. At the same time, it is also necessary to conduct in-depth research on the optimal design of the communication operation data collection system based on the linear equation algorithm, so as to provide suggestions for improving the quality of communication operation data collection. The linear equation has a good optimization effect on the safety and accuracy of broadband carrier communication information collection, and can reduce the interference of redundant data and irrelevant data in the real-time collection process, laying a solid foundation for the normal operation of the intelligent centralized reading system and low-voltage visualization system base.
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Funding information: The authors state no funding involved.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Conflict of interest: The authors state no conflict of interest.
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