Low-voltage Circuit Breaker Intelligent Controller Design

The paper grounds on a design and development automation project of universal air circuit breaker of a low-voltage electrical plant in Jiangsu, and according to the enterprise's demand mainly researches development and re-design of the original circuit breaker for the problems of unperfect function, inconvenient setting operatin and unfriendly man-machine interfaces, and researches how to keep reliability of the breaker, increase the level of automation and intelligence and simultaneously reduce the product cost as far as possible. So, this paper has certain practical significance and application prospect.Among this subject, the intelligent controller regards MSP430 MCU which TI Company produces and CPLD as the key procsssor. The intelligent controller incorporates the functions of measurement, protection, monitoring and communication. The paper discusses the software design of the intelligent controller based on the full study of arithmetic of measurement and principle of protection in the way of the modular design of software design. Meanwhile, the paper discusses the anti-jamming methods of both hardware and software to enhance anti-jamming ability of the intelligent controller, so as to ensure the reliability of the breaker.For the breaker's "four remotion" communication requirements, the paper studies Modbus fieldbus communication protocol which is widely used in low-voltage electrical fields, and bring forward a plan of intelligent controller communication network based on Modbus fieldbus, which realizes the communication of intelligent controller and PC, and is good for the PC's centralized monitoring and management to the intelligent breaker.