10 KV Distribution Network Fault Current Limiter

With the continuous development of the power system,10 kV distribution network plays an increasingly important role for a wide range of users.Fault current limiting technology is also evolving constantly.According to the new development trend,the current limiting air-core reactor and the current breaker are commonly combined.In addition,The protection algorithm is an important part.Based on the introduction of the existing protection algorithms,a new algorithm is proposed.And the other two modules include signal acquisition module and controller module.Then the detailed design of each module are introduced.The overall working principle of the fault current limiter are introduced firstly.Then describing the control unit section and signal acquisition section separately.Proposal of protection algorithm.Several existing protection algorithm are included to analyze the current waveform under the special situation in this article.Aiming at the shortcomings of existing current detection algorithms,a new protection algorithm is proposed.Then various algorithms are simulated through the Matlab and error is analyzed.Finally,the comparative analysis determines the reliability of the new algorithm.The corresponding signal acquisition module is designed in the article.It mainly collects the current signal and displays the current signal waveform.This section introduces various modules of the data acquisition device.A/D conversion circuit,signal application,power supply circuit are included.Then the article designs the corresponding schematic diagram.The design of the control unit includes the core control CPU circuit section,power circuit section,on-off module,external memory module.Then each module hardware circuit diagram are designed.The design of the software.This paper combines the whole application system to design the software system of each function module.According to the current sampling circuit part,the current sampling flowchart is given.The new protection algorithm is introduced,and writing software section in use of CCS3.3 software.The design of the primary equipment.The protective current transformer are included,and then describing the parameters in detail.Section of the high speed circuit breaker.Its parameters are introduced and calculating the rated breaking current and maximum breaking peak current value.The application of the distribution system determines the matched circuit reactors.The type of current-limiting reactor is selected,the corresponding dynamic stability and thermal stability check meet the requirements.