Research And Implementation Of Low Voltage Power Network Intelligent Circuit Breaker

Nowdays, power grid become more and more intelligent in every aspect, the intelligent circuit breaker(ICB) is the key equipment to ensure electric distribution network safe and reliable. Its main function is to protect the line current. The existing circuit breaker is generally used as a 32-bit DSP processor as the core part of the intelligent control, that can fulfill the protection requirements of power grid currently. However, with smart power grid expanding, the parameters measurement of power grid requires ICB more accurate, speedy trouble solving and diversified function. Therefore, ICB inevitably faced innovation. It has great research significance and application value to conduct the research on ICB for low voltage electrical manufacturing industry. Under this background, this paper design an intelligent circuit breaker based on dual processor with DSP + ARM structure. The two separate CPUs work cooperatively according to the different functions.First of all, this paper introduced the background and development trend of the circuit breaker both in domestic and abroad environment before the functions and characteristics analysis were given. The principle of the power grid also was introduced following the system design aiming to realize the functional requirements and to satisfy relevant performance indicators where dual CPU hardware was proposed. Second part included description of separate hardware modules and functional modules in the hardware. This part presented three principles of current protection in detail. By using fast Fourier transform(FFT) in protection algorithm, electric parameter measurement was decided. The function of the software design corresponding to implementation functions, the design idea and software flow chart were given. Finally, by improving both software and hardware in the system, this investigation successfully complete the acquisition system and data collection process, hardware and software module testing, in the laboratory simulation of low voltage power grid protection with this device tested.Experimental results show that design ideas are clear and reliable. The protection action is quick and extensible with expecting design goal.