| With the increasing demand for energy, the automation degree of coal mine industry is also increasing; however, the accidents of coal mine still occur frequently. Therefore, it's imperative to develop the smart feeder switchgear, which is more sensible and reliable. This design of flameproof vacuum feeder switchgear brings important value and practical significance to safety production of coal mine.This paper makes a detailed analysis on the neutral point ungrounded mine power system on theory, and takes the ST's new STM32 microprocessor as the core of design, has finished the relevant design on hardware and software. Furthermore, in allusion to various disturbances that the system may face, this paper designs the anti-jamming from hardware and software aspects. Finally, experimental data validate the reliable characteristics of protection of the whole system when various faults of lines appear.This design puts forward using direction-based zero sequence current selective leakage protection principles, and its feasibility is verified by phase comparison circuit; what's more, we designed the hardware circuit of lower computer, CAN-USB converter interface of PC and monitoring interface of test system; In addition, synchronous sampling and full-wave Fourier algorirhm is successfully applied to the STM32 processor's data acquisition and processing, effectively improve the sampling accuracy.The real operate condition on mine show that this protection system has stable performance and reliable action, effectively improved the safety and reliability of mine power system. |
PDF Full Text Request