INVESTIGATION OF PLC LINE OPERATION RELIABILITY AT UNBALANCED ES VOLTAGE

ИССЛЕДОВАНИЕ НАДЕЖНОСТИ РАБОТЫ ЛИНИЯ PLC ПРИ НЕСИММЕТРИЧНОМ НАПРЯЖЕНИИ ЭС

Лепешкин Николай Сергеевич

студент, кафедра Техническое и информационное обеспечение проектирования и функционирования электроэнергетического хозяйства потребителей, Казанский государственный энергетический университет,

РФ, г. Казань

Марзоева Ирина Владимировна

научный руководитель, канд. филол. наук, доц., Казанский государственный энергетический университет,

РФ, г. Казань

ABSTRACT

The study of the reliability of power line communication (PLC) performance under unbalanced grid voltage is an important area that requires research attention in the context of ensuring the stability and efficiency of communications in electrical networks. Which includes the analysis of signal modulation, the application of different transmission standards and protocols, and the features of the physical layer of communication in PLC systems.

АННОТАЦИЯ

Исследование надежности работы линии передачи данных по электропитанию (PLC) при несимметричном напряжении электросети представляет собой важную область, требующую внимания исследователей в контексте обеспечения устойчивости и эффективности коммуникаций в электрических сетях. Которая включает в себя анализ модуляции сигнала, применение различных стандартов и протоколов передачи данных, а также особенности физического слоя коммуникации в системах PLC.

Keywords: PLC, voltage, interference, systems, transmission.

Ключевые слова: PLC, напряжение, помехи, системы, передача.

PLC (Power Line Communications) technologies of data transmission over power lines have quite a long history of their origin and have found their application in many spheres of human activity for various systems of remote monitoring, data acquisition and transmission using existing power lines, for example, in complex security systems, in systems of remote parameter monitoring and distributed control, in automation of buildings and facilities of special regime, etc. The technology of data transmission over power lines has significant advantages. Data transmission over power line wires has significant advantages, which include: 1) low initial capital investments, as the construction of the network does not require works related to cable laying; 2) rapid deployment of the network; 3) the possibility of providing services in almost all places where there is a power line.

The use of power lines as a reliable medium for data transmission is not an easy task. Worn wiring and its poor quality, the use of stranded wires as wire connections have a negative impact on data transmission in older apartment buildings. In such buildings often as the main metal of the wiring was taken aluminum, which has a lower electrical conductivity compared to copper. Accordingly, PLC technology will work best in newer buildings, which, as a rule, use modern technology and copper wiring. The reliability of data transmission is strongly influenced by interference from various electrical appliances, daylight lamps and other factors that create noise in the wiring. The biggest contributors are impulse interference from electric motors, welding equipment and microwave ovens. However, reliable methods of data encoding and encryption used in modern PLC-technologies provide not only a high level of reliability in information transmission, but also its protection from unauthorized access» [1].

When organizing communication, electromagnetic compatibility must also be ensured, i.e. it is necessary to reduce side electromagnetic emissions arising in the process of data transmission. In many respects, the orientation of PLC-technology for use in small and home offices (Small Office/Home Office - SOHO) is due not only to the simplicity of implementation and mobility of devices based on it, but also to the fact that this technology is most effective only in the so-called last mile. The data transmission speed decreases sharply as the distance increases.

There are also requirements for this line. PLC technology must meet certain requirements. For it the following limitations in the field of communication are applicable: - the working frequency range for narrowband PLC should be from 0 to 500 kHz, for broadband PLC - from 2 to 200 MHz; - to provide broadband access to utilities should be used BPL (Broadband over Power Line) technology with the appropriate policy and license. In studying this problem, the main factors highlighted were [2]:

1) Signal distortion:

The mains voltage can be subjected to various distortions such as voltage drops, peaks and sags. These variations can distort the PLC signal waveform, which can make it difficult to decode properly at the receiving end. To cope with these distortions, PLC systems can utilize signal pre-processing techniques such as filters and compensation methods.

2) Signal degradation:

Variable voltage levels can cause temporary fluctuations in the amplitude of the PLC signal. This phenomenon is called jitter and can lead to degradation of communication quality. Techniques such as PLL (phase locked loop) can be used to control jitter and stabilize the signal.

3) Increased probability of errors:

Changes in voltage can cause changes in noise and interference levels, increasing the probability of errors in data transmission. The use of error correction such as BCH (Bose-Chaudhuri-Hocquenghem) codes can help in recovering data when errors occur.

4) Deterioration of communication stability:

Power surges can cause loss of synchronization between transmitter and receiver. PLC systems can be equipped with automatic phase and timing correction algorithms to maintain stable communication.

5) Occurrence of interference:

Unstable voltage can contribute to the occurrence of electromagnetic interference. Filters at the receiving end as well as multi-probe signal detection techniques can be used to reduce the effects of interference.

6) Loss of bandwidth:

Under conditions of voltage instability, dynamic bandwidth control of the PLC line may occur. This includes changing the data rate, selecting optimal frequencies and using multiple access techniques to efficiently utilize the available bandwidth.

References:

1. Sabirzyanova, A. S. Digital substation as a tool for increasing reliability of power supply / A. S. Sabirzyanova, G. Z. Gilyazieva // Энергетика и энергосбережение: теория и практика : СБОРНИК МАТЕРИАЛОВ VII МЕЖДУНАРОДНОЙ НАУЧНО-ПРАКТИЧЕСКОЙ КОНФЕРЕНЦИИ, Кемерово, 07–09 декабря 2022 года. – Кемерово: Кузбасский государственный технический университет имени Т.Ф. Горбачева, 2023. – P. 339-1-339-4. – EDN DZRZQH.
2. Адиев Т.И. Применение предварительной коррекции в системах с ортогональным частотным мультиплексированием // Диссертация: 2015.