Forecasting Analysis of Future Development Direction of Smart Meters

With the increasing use of smart meters, there are more and more favorable effects on our lives. At the same time, we are also subtly changing our lives.

According to China Power Grid proposed a master plan, and summed up the development of China's power grid meter in the past 10 years, we can conclude that: to achieve meter automatic meter reading, the premise is that the meter needs to first achieve intelligence, so as to achieve data exit, with To achieve the purpose of centralized meter reading, there are several forms of electricity meters commonly used at home and abroad for centralized meter reading.

1. Electromechanical combined meter The first type of electromechanical combined meter is based on the original mechanical meter, equipped with electronic counting device and the corresponding control, communication circuit, or with IC card reader interface In order to achieve automatic metering, billing and control; the basic structure is to punch or smear the material on the turntable of the original mechanical power meter to absorb light. Through photoelectric conversion, the rotation of the mechanical turntable is converted into electrical pulse signals. , and then perform the corresponding count processing.

Since the metering principle of this kind of meter has not been changed, its metering accuracy and characteristics are exactly the same as the mechanical meter, and the cost is relatively high. The advantage is that it can make full use of the large number of mechanical meter installed and in use, and its The measurement principle is familiar to the public and easy to accept.

Another type of electromechanical combined meter is the use of electronic metering circuit in the digital pulse signal, through the micro-motor driven word code wheel to get the energy count, this structure is the most concise and practical electronic meter The program, but unfortunately its higher requirements for the measurement circuit, that requires all the tables are converted to a corresponding number of digital pulses according to a fixed ratio, in order to drive the micro motor to rotate the word wheel at the correct speed .

This ratio is the so-called ammeter constant (imp/kWh). Because the timing components used in the circuit to determine the pulse speed are mostly resistive and capacitive components with large discrete parameters, in order to ensure the metering accuracy and product consistency of the meter, It is necessary to strengthen the screening of components and the adjustment of semi-finished products in the production process, that is to say increase the input of manpower and material resources and prolong the production cycle, so that the production cost and cost of the power meter increase. In addition, the meter of this kind of structure has no difference with the old-fashioned mechanical watch in terms of data collection and user payment, and should be a phase-out product.

2. All-electronic meter All-electronic meter is the most advanced type of electric meter in China today. It adopts advanced single chip microcomputer technology and specially designed integrated circuit for energy measurement. It has high measurement accuracy and can prevent theft. Electrical, low loss and high reliability. Some of these models also have dual billing functions. Since the electricity consumption data of such a power meter has been digitized, it can be easily combined with various data collection and transmission circuits to form an automatic metering and billing system. This is a new generation of existing household electric meters. Use will save the power metering department a large number of meter reading calculations, and timely recovery of electricity (pay first after the use of electricity), with great economic and social benefits.

(1) Centralized meter reading in the bus system: The meter part adopts a smart meter, and the smart meter signal lines of each household are connected in parallel on a bus. The bus is connected to the downstairs adapter, and each floor adapter is connected to the concentrator of the district. Concentrator centralized power supply.

(2) Power Carrier Meter Reading: The centralized power meter reading system is a centralized meter reading system that directly utilizes the existing low voltage transmission lines for data transmission, eliminating the need for a wiring line project. The system integrates microelectronics, communication technology and computer technology in one high-tech product. It is highly reliable and simple to install. It is widely used in metering and monitoring of electricity and gas meters in urban and rural areas.

However, because the power line is used to transmit electrical energy to electrical equipment, rather than to transmit data, the power line has many restrictions on data transmission: (1) The distribution transformer has a barrier effect on the power carrier signal, so the electrical carrier signal can only be A distribution transformer transmits within the area; (2) Different signal coupling methods have different losses for the power carrier signal; (3) The power line has its own inherent impulse interference. In addition, high power line reduction, high noise, and high distortion make the power line an unsatisfactory communication medium. However, due to the development of modern communication technologies, power line carrier communication becomes possible. The signal-to-noise ratio of the data signal determines the transmission distance. . The key to power line carrier communication is to use a powerful Powerline carrier dedicated Modem chip.

Full electronic meter system consists of:

(1) Remote table. Meters with pulse output such as water meter, electricity meter, gas meter, and hot meter are remote meters. The metering method is the same as the traditional meter. The difference is that the pulse output function is added to the original base meter. Each pulse represents a certain measurement value. . The collector collects pulses through the pulse output port of the remote table.

(2) Collector. The collector can simultaneously collect the pulse information of water meters, electricity meters, gas meters, and heat meters, and convert these pulse information into physical quantities for measurement and storage in the memory of each collector. Through the management of the microcomputer, you can query any system A user's energy consumption information is uploaded to the user's information under the management computer's meter reading and other commands.

(3) Converter. The main task of the converter is to complete the data communication work with the collector, release the power data freeze command to the collector, periodically receive the collector's power data or receive the data of a certain meter or a group of meter according to the system requirements. According to the system requirements, the communication with the master station is completed, and user power data and other information required by the master station are transmitted to the master station database. The downlink channel refers to the communication line between the converter and the collector. There are mainly three methods: bus meter reading system, carrier meter reading system, and infrared meter reading system. The upward channel of the communication channel refers to the communication line between the converter and the master station, and may use communication media such as telephone, wireless, and dedicated lines.

(4) System management software functions. The system management software is based on communication, with the database as the core, providing data processing, query, statistics, reporting, backup, and other functions; using a combination of object-oriented and modular methods to flexibly support different customer requirements, such as special format reports, Authority control, etc.; holding the customer's original management system, can interface with other management software, provide data interface and communication interface, have network communication function; can manage multiple cells at the same time, set communication parameters for each cell; power meter management, set the meter The original parameters, address, and its status; rate management, can be arbitrarily set a variety of rates, set the unit price of each energy; user management, management and control of the amount of each household, management of the user's settlement; real-time meter reading function, The system can capture the real-time data of each energy meter; the cost is automatically calculated and the average energy loss of the public energy is realized.