The Research And Design Of Intelligent Controller Of Low Voltage Circuit Breakers Based On CANOpen Bus

Low-voltage circuit breakers is to protect the electrical distribution networks and industrial equipment from overload, short circuit and leakage and other important electrical components against malfunction. Intelligent controller is the core control unit of the realization of measurement and protection functions. This paper reviewed and summarized the development process for low-voltage electrical industry trends of the intelligent controller, and committed to the design work of communication intelligent controller for low-voltage circuit breaker, researched and designed a fieldbus-based CANOpen Intelligent Circuit Breaker controller.(1) Analyzed the circuit breaker situation and development trend of the research, pointed out the limitations of the traditional circuit breaker function, and elaborated high level demand on applications of intelligent circuit breaker in the electrical distribution protection system. On this basis, this paper researched the intelligent controller technology:measurement principle of power parameter, the current three pahse protection features and CANOpen bus technology.(2) According to national standards and enterprise standards and considering functional requirements of the project, put forward the overall intelligent control system circuit breaker program. This paper designed DSP control module system, power control module, the DIP switches module, communication module, signal conditioning module.etc, described the composition of the module circuit theory and methods in detail, then gave out the entire circuit system schematic.(3) Described the software design, combined with the hardware circuit, then designed system application programs, discussed the implementation method of current three-segment protection procedures and CANOpen slave protocol stack program in detail, and gave the system software design process and some code implementation.(4) On the platform of QQ2812 development board, combined with DSP emulator and software CCS2.2, debug the system software and over again, gave the results, while communications checked through USBCAN PC CAN converter and functional test software, and verified slave CANOpen communication, simple test methods were given.Final test and operation results showed that the intelligent circuit breaker designed to stabilize the realization of three pahse current protection, and regulation accuracy of current and time,other technical specifications have reached the desired requirements, the basic bus traffic control to meet the functional requirements.