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This post was last edited by chenjinfeng on 2020-2-21 at 15:46. The distribution network is an important component of the power system, responsible for the efficient distribution of electrical energy; therefore, its safe and stable operation is of great significance to the entire power system. 10kV distribution lines are the most numerous and structurally complex part of the distribution network. To improve the power supply reliability of 10kV distribution lines and ensure their safe and stable operation, it is essential to install appropriate microcomputer-based protection systems. Based on this, this paper designs and develops a microcomputer-based protection and monitoring device for 10kV lines. It reviews the domestic and international research status, requirements, and development trends of microcomputer-based protection, analyzes the basic protection principles and algorithms for 10kV microcomputer-based protection, and presents the system architecture of 10kV microcomputer-based line protection and monitoring devices, which includes 10kV busbars, microcomputer-based protection and monitoring devices, circuit breakers, users, and a back-end monitoring and processing center. The hardware design of the device is presented; based on the modular design concept, it is divided into four main modules: the protection module, the measurement module, the human-machine interaction and communication module, and the power supply module. Among them, the protection module uses the high-performance floating-point DSP chip TMS320F28335 as its control core, and is responsible for performing logical judgments related to protection as well as implementing the protection functions; the measurement module makes use of the dedicated measurement chip ATT7022B to collect measurement data; the human-machine interaction and communication module relies on the STM32F103VET6 microcontroller as its control chip to handle functions such as the human-machine interface and communication; the power supply module employs an AC-DC switching power supply to provide DC power, and utilizes voltage conversion circuits to deliver the required voltages for the various devices. The software design of the device is presented, including the implementation of the main program in the CCS development environment, as well as the design of relevant interrupt subroutines such as the A/D sampling subroutine, frequency measurement subroutine, protection judgment subroutine, human-machine interaction subroutine, and communication subroutine. At the same time, corresponding hardware and software anti-interference measures were designed to ensure the reliable and stable operation of the device. After debugging and testing, the device is capable of performing the required protection functions, and the measurement data achieves the desired accuracy, fully meeting the operational requirements of power systems.