Abstract : This paper analyzes the composition, principle, and characteristics of microcomputer-based integrated protection devices, pointing out that the application prospects of microcomputer-based integrated protection devices are quite promising. Keywords : Microcomputer-based integrated protection device; relay protection; application 0 Overview At present, the high-voltage electrical appliances in industrial and mining enterprises' substations adopt traditional relay protection methods, which require many relays, resulting in large relay protection panel areas and cumbersome setting, which cannot well meet the requirements of modern technological development. If microcomputer-based integrated protection devices are adopted for transformation, automated management can be achieved, labor intensity can be reduced, and the reliability and accuracy of the electrical system will also reach a new level. [b]1 Device Composition and Principle 1.1 Hardware Composition[/b] Microcomputer-based integrated protection devices generally adopt a plug-in structure, typically including AC conversion plug-in, analog-to-digital conversion and microprocessor plug-in, human-machine management plug-in, switch input plug-in, power supply plug-in, and relay plug-in, etc. Although the microprocessors and analog-to-digital conversion methods used in products from different manufacturers are different, the structural principle of microcomputer protection devices is basically the same. Analog-to-digital conversion includes two different methods: A/D and VFC. Switching inputs and parallel outputs are generally opto-isolated to enhance anti-interference capabilities. With the development of microprocessor technology, more and more resources are integrated internally; a single processor chip often constitutes a complete microprocessor system. More complex microcomputer protection devices typically employ a multi-CPU structure. 1.2 Principle The principle of microcomputer-based integrated protection varies slightly depending on the protected object and the application (mainly the type of equipment). Different protection structures require different analog, digital input, and digital output quantities to be acquired. Although a microcomputer protection device integrates many protection principles, these principles remain relatively independent. External current and voltage inputs are transformed by isolation transformers, then input to the analog-to-digital converter via low-pass filters. After sampling and digital processing by the CPU, various protection relays are formed, and various telemetry measurements are calculated. IA, IB, IC, IOH, and IOk are analog inputs for protection, while MIA, MIB, and MIC are dedicated measurement CT inputs for measurement, ensuring sufficient accuracy in telemetry measurements. The UA, LIB, and UC inputs in this device are mainly used for voltage measurement, and together with MIA, MIB, and MIC, they are used to calculate the P, Q, COS, Kwh, and Kvarh of the circuit. The device schematic is shown in Figure 1. [b][align=center]For more details, please click: A Brief Discussion on the Application Prospects of Microcomputer-Based Integrated Protection Devices[/align][/b]