With the rapid development of China's economy, the demand for electricity is increasing, and the unbalance of power consumption at different times is becoming more serious. In order to alleviate the increasingly acute contradiction between power supply and demand in China, improve the unbalanced electricity consumption, comprehensively implement the peak, flat, and valley time-of-use electricity price system, improve the country's electricity efficiency, and make rational use of power resources. The power departments of some provinces and cities in China have gradually launched multi rate prepaid energy meters to charge users' electricity consumption in time.

Electric energy meter is one of the basic equipment for data acquisition of smart grid (especially smart distribution network). It undertakes the task of original power data acquisition, measurement and transmission, and is the basis of information integration, analysis and optimization and information display.

In addition to the metering function of ordinary electric energy meter, the prepaid energy meter has intelligent functions such as bi-directional multi rate metering function, user control function, bidirectional data communication function of multiple data transmission modes, and anti electricity stealing function in order to adapt to the use of smart grid and new energy. In particular, can only use electricity after purchasing electricity. If the user does not continue to buy electricity after using up electricity, it will automatically cut off the power supply and stop the power supply. It is used to measure AC single-phase active electric energy with rated frequency of 50 Hz and realize the management function of paying first and then using electricity. Advanced microelectronic technology is used to collect, process and save data, and RF card is used to transfer data. Its performance index meets the standards of GB/T17215-2002 and GB/T18460.3-2001. It has the characteristics of small size, high security, high reliability and anti stealing power.

The demand of electric power system management department for prepaid energy meter is diversified. The following is a variety of energy meters prepaid functions required by some power system management departments and specific users:

1) Measuring and storage function. It can measure single and bi direnctional active and reactive electric energy in various time periods, and complete the measurement and display of current power, demand, power factor and other parameters. The electric energy meter can store the data of the last meter reading cycle at least.

2) It can meet the needs of electricity information collection. According to the requirements of the power consumption information acquisition system for collection data items, collection period and power meter management, the types, configuration functions, standardized communication methods and communication protocols of smart power meters are designed to lay the foundation for accelerating the construction of power information collection systems. the types and configuration functions of intelligent electric energy meters, standardized communication methods and communication protocols are designed. In addition, remote prepaid energy meter reading reduces the workload of on-site meter reading, and also reduces the inconvenience to users. The level of high-quality service will be further strengthened.

3) Monitoring function. The prepaid energy meter can monitor the user's power and maximum demand, and prevent the electricity stealing behavior by analyzing the power load curve of the user. Users can also obtain their own power consumption information directly from the electric energy meter, which greatly improves the right to know about the power consumption information of users, and provides convenience for users to change the power consumption mode and implement effective power consumption control.

4) Control function. The prepaid energy meter can control the user's time period and load. The former is used for multi rate time-sharing billing; the latter refers to receiving remote control instructions through communication interface or controlling load through internal programming (considering time period and load quota) of meter. The electric energy meter can not only complete the prepaid function, but also have the control function of alarm delay and power cut when the prepaid energy will be used up.

5) Management function. The electric energy meter is connected with the communication network or meter reading system of the power system through the communication interface to realize the remote data exchange with the outside world. The client server with authority in the power network can set the time period, period rate, period power limit, remaining power alarm limit, representative day, freezing day, mode of demand, time and slip by using the address code of electric energy meter (generally 12 decimal digits); call and view the real-time power of customers; read the relevant power consumption According to the demand, the electric energy measurement information is transmitted to the corresponding departments for system dispatching, electric energy control, electric energy exchange and business accounting.

The prepaid energy meter have the following advantages:

1) It can solve the problem of labor cost

After using the prepaid electric energy meter, the labor cost is greatly reduced, and the related work is more smooth. Electric power workers do not need to read meter on-site, at the time of monthly payment, users will consciously pay the fees.

2) It can solve the problem of difficult charging

In real life, there are some users who are in arrears to pay the electricity bill. Sometimes, there is no one at home when the electricity collection personnel comes to the door. All kinds of situations make it very difficult to pay the electricity bill. Now, with the use of prepaid energy meters, users have to pay in advance for electricity before they can use electricity. The staff do not need to come to the door to collect fees. At the same time, users pay their electricity bills on time.

To sum up, the use of prepaid energy meters can solve some problems of relevant staff, not only allows users to pay fees consciously and efficiently, but also can relieve the service pressure of staff in charge collection, and make the cooperation between users and power departments more convenient and concise.

Smart electric energy meter is an indispensable part of the development of a strong smart grid. Promoting the application of electric energy meters is of great significance in terms of product quality improvement, power collection construction, and smart grid construction.