Today science and technology advances, productivity continues to develop, three-phase electricity in industrial production has played a crucial role. In particular, some motor and high power devices use the more common, but in industrial, enterprise and rural areas, three-phase motor for some reason the phenomenon of burning a lot of damage, mainly because of lack of three-phase power phase-phase, undervoltage and caused. This involves the three-phase power protection relay is by detecting whether the lack of three-phase power phase-phase, voltage and other issues to the protection of the motor in a timely manner to minimize economic losses. Based on the analysis of the motor protection device at home and abroad and present research based on the design of a PIC12F675 microcontroller to control the core, set off phase,-phase and undervoltage fault protection and other multifunctional three-phase motor protection relay.
This article first phase off the motor, and other common-phase-voltage electrical faults are analyzed in detail, combined with PIC12F675 MCU features, presented high reliability, the failure to implement strong protection of realization. The system uses the method of step-down transformer to the chip to provide a stable, reliable power. And through the LED to feedback to the user information. .
According to the text proposed by the various types of fault protection implementation methods, design and implementation of a complete motor protection hardware, protection devices are given a complete system software solution.
Key word: Three-phase power,motor,chip, protcetion relay