Plc-based Electricity Billing System

This project is mainly supposed to design a reliable smart electricity metering system based on power line carrier communication (PLC). The system realizes systematization, automation and intelligentification of functions from power measurement, breaker control, PLC, all the way to centralized data management.Moreover, the system can save a great cost of reinvestment by directly modifying the mechanical electricity meters in use to achieve meter reading, thus being propitious to efficient use of resources and promoting the popularity of automatic meter reading. The system mainly consists of three subsystems (or modules): the upper computer system (PC Terminal, hereinafter referred to as UCS), the lower computer system (User Terminal, hereinafter referred to as LCS), and the PLC modem.The UCS is a user interface that is integrated with device management, user account management, data management, and other functions of the sort. Device management refers to assignment of the LCS ID, communication parameter settings and data exchange with the LCS. User account management mainly refers to user account adding and deleting, and authorization management. Data management mainly refers to management of citizens'registration information, energy consumption log and statistics.The LCS instantaneously collects readings of the electricity meter and stores them in an external ROM. When it acquires the command to report its reading, it packs the data to send. The data packet is modulated by the PLC modem on the LCS'side and then coupled to the power line, and then demodulated by the PLC modem on the UCS'side, and at last sent to the UCS via a serial interface; vice versa. Also, the LCS acquires and executes other commands by the UCS.As a repeater, the PLC modem offers a transparent data channel, i.e. it is entirely independent from the protocol, thus making it easier to constitute a protocol.