Selected Topics in Energy, Environment, Sustainable Development and Landscaping Introduction of Automatic Meter Reading systems in Electro-distribution Zrenjanin LILIJANA ðUKIĆ PETROMANJANC1, DUMITRU MNERIE2, GABRIELA MNERIE2 1 Elektrovojvodina , Jovana Trajkovica 11/b, 23000 Zrenjanjin, SERBIA 2 Mechanical Engineering Faculty, POLITEHNICA University of Timisoara, Mihai Viteazul, 1 ROMANIA [email protected], [email protected], [email protected] Abstract: Electro-distribution Zrenjanin is currently undertaking reconstruction of the electric power grid. The objective of the project is to increase compatibility of distribution and transmission system in Zrenjanin and to decrease commercial and technical losses. The entire project includes the re-construction of the existing and construction of the new low-voltage grids, transformer and switching stations, delivery and installation of new measuring equipment in 10 (20)/0.4kV stations and construction of the new AMR (eng. Automatic Meter Reading) centre for remote readout of residential electric meters. Installation of reliable measuring equipment will enable Elektrovojvodina Zrenjanin to continuously monitor residential power consumption and to quickly uncover all potential thefts of electricity. This will result in decreasing losses and increasing profits. Reliable and accessible information from the electricity consumption distribution system’s measuring stations, will create conditions for better grid management and consequently lower the risks of overload and electrical grid equipment failures. Key-words: electric meters, AMR center, remote readout, electrical power consumption, reliability electric meter readouts creates conditions for use of 1. Introduction advanced communication methods, remote readout, The improvements in quality of life and living quality control of the delivered electrical energy, standards necessitate increases in electrical power data-acquisition and analysis, all without having to consumption, which leads to the need for maintain physical employee access to the continuing development of the electrical power grid measuring equipment. New electric meter readout system. Growing system results in increasing system will enable employees of electrical power technical losses of electrical energy. After distribution companies currently performing analyzing the situation on the territory of physical readouts, to faster, better and easier Elektrovojvodina Zrenjanin, initial results have perform their tasks. shown that total losses off electrical energy are somewhere in the proximity of 25 to 30%. To decrease the losses, efforts should be made to increase the quality of the electrical energy, at least 2. What is Automatic Meter Reading for primary parameters such as voltage (AMR) ? fluctuations, number of power failures etc. Automatic Meter Reading is the remote acquisition Systematic approach has been employed to of electric meter’s data. It is a readout performed address the observed problems. Reconstruction of without physical or visual access to the meter. the electric distribution grid, including the Modern remote readout trend of measuring reconstruction of the existing and construction of stations is continuously growing in the world. the new low-voltage power lines, transformer and Definitive priority is to initially replace electric switching stations and application of the new meters of the largest consumers (SN buyers and measuring system AMR (Automatic Meter industry) primarily to record peak consumption Reading) for remote readout of electric meters, is data and peak consumption curves (15 minute currently underway. In order to identify the losses, average consumption). immense task of analyzing and sorting the data in However, EU countries are also replacing respect to the installation locations, still remains. residential electric meters. Therefore we can Introduction of green technologies in the field of conclude that the majority of countries are planning ISSN: 1792-5924 / ISSN: 1792-5940 294 ISBN: 978-960-474-237-0 Selected Topics in Energy, Environment, Sustainable Development and Landscaping to replace all electric meters, high consumption b) communication through low voltage power grid commercial and residential. AMR has some significant advantages and 2.1. Direct communication benefits for electrical power distribution companies Communication with electric meters is established such as: using GSM, PSTN, ISDN networks or Internet. a) decrease in readout costs: traditional readout These meters are equipped with the following methods demand significant workforce and they communication channels: optical interface, serial represent an important factor in the cost of doing interface CS, RS 232 or RS 845 (485) or business. Besides labor costs there are also communication module which contains these transportation, clothes, footwear and other interfaces. expenses. Communication protocols are IEC 62056-21 b) difficult access to electric meter equipment: in mod C and IEC 870-5-102, data transfer speeds are most cases, especially for old installations. 300-19.200 bit/s. Electric meters are located in poor locations Communication module with GSM (GPRS) making their access very difficult (property modem has a small antenna on the front and slot owner is usually not available to provide access for the SIM card on the back. to the meter). This necessitates many attempts to Also available is «Euridis» serial perform the necessary readout, and increases the communication remote readout and programming costs significantly. system which uses OBIS data identification c) improvements in quality of services and greater method. Communication input of the meter is customer satisfaction: customer satisfaction is connected to the magnetic probe which is used to one of the key components for successfully connect the meter to the computer running doing business in the free market environment. application for meter readout and programming. Old methods for calculating electricity consumption were based on invoicing customers on the basis of estimated consumption. This 2.2. Communication through low resulted in the continuous customer complaints voltage power grid and demands for corrections. AMR system This type of communication with electric meters is creates conditions for remote meter readouts and conducted using PLC (Power Line Carrier) or DLC invoicing based on the actual consumption, (Distribution Line Communication) network. increased accuracy resulting from elimination of Remote household electric meter readout human factor and early warning of potential through low voltage power grid system consists of: electric meter equipment failures and similar. a) electric meter equipment with the DLC modem d) correction of prices in the real-time based on b) concentrator which collects data from low various pricing models: AMR creates conditions voltage power grid electric meters for introduction of variable price points which c) software for processing data from all take into account the time of day when the concentrators consumption occurs. Such flexible pricing Electronic electric meters are equipped with models can stimulate consumers to use electrical the following communication channels: optical energy during times of lower consumption, interface IEC-62056-21 (IEC 1107 mode E) which is in the best interest of everyone. program, DLMS/COSEM protocol DLC modem e) less time between the readout and the accounting and M-collector. Optical interface is used for local of electric energy consumption electric meter programming and data collection. f) increased theft prevention and discovery. DLC modem is used for remote to a Besides the above, AMR also: communication. It is connected to a low-level a) limits the power to the consumer according to power grid externally and it uses a single phase the agreed energy consumption level internally. DLC works utilizing CENELEC b) remote disconnection and connection frequency range A (9 kHz to 95 kHz) which is c) advance payments reserved for low voltage power grid data d) measurement control communication. Communication between the e) access of the consumers to the data modem and the concentrator is 300 – 1200 bit/s. f) antitheft alarm systems Data concentrator is a computer running g) intelligent household appliance management Microsoft Windows CE operating system. It is system usually installed in the transformer stations (low h) distribution automation voltage side), but it can also be installed in other There are few elementary AMR communication locations if this results in better communication or systems models of operation: access. Concentrator communicates with electric a) direct communication or readout meters through the existing DLC modem (using all ISSN: 1792-5924 / ISSN: 1792-5940 295 ISBN: 978-960-474-237-0 Selected Topics in Energy, Environment, Sustainable Development and Landscaping three phases), and with the central processing 3. SYSTEM DESCRIPTION center using the built-in GSM communication modem or using Internet. All the data, as well as Concept of the new system for electric meter remote the program itself are stored in the CF memory readout is shown in Picture 1. Software system card. Single concentrator can process all the which will automatically perform daily readout of parameters from 1024 meters (due to addressing all electric meters and record collected information limitations). into a database, will be installed at the AMR centre. Based on the preset parameters, concentrator Role of