The traditional electric meter system has some shortcomings, such as inaccurate measurement, time-consuming and laborious manual meter reading, and tedious statistics. With the development of network technology, the network has been everywhere, and people's lifestyles have also changed. Aiming at the shortcomings and shortcomings of the traditional electromagnetic watt-hour meter, combined with the current network technology, an automatic meter reading system based on Ethernet transmission is studied and designed. The hardware, software and communication design of remote power data terminal are emphatically introduced. Electric energy remote terminal (hereinafter referred to as ERTU) is an important part of electric energy metering and charging automation system. The electric energy metering and charging system with high automation, reliable operation and convenient maintenance has become an important link in the automation transformation of power system. Based on the design of remote power data terminal, this paper introduces the concept of real-time embedded system into the traditional electric energy acquisition system according to the application requirements of practical engineering. The system makes full use of RTOS's multi-task ability and modular simplification function, and has strong advantages in execution efficiency, program volume and communication processing ability. During the design and implementation of the system, a set of application protocols based on TCP/IP (PRMP) is defined for the communication between the substation and the main station, which effectively solves the communication problem. The various algorithms of electric energy collector are emphatically analyzed, and their problems are pointed out. Based on the theoretical derivation of Fourier algorithm, the amplitude algorithm and high-precision frequency measurement algorithm for eliminating decaying DC component are proposed. The new amplitude algorithm does not make any assumptions and requirements on the attenuation time constant τ: the frequency measurement algorithm tracks the system frequency with high accuracy by adjusting the correction coefficient in real time according to the errors existing in the traditional Fourier frequency measurement algorithm.