Online Monitoring For Vacuum Degree Of The Switchgear

With the highly increasing demand of the safety factor for the power system, the online monitoring technology is being paid more and more attention.This paper first introduces the basic components of the switchgear and describes the relevant characteristics of the arc chamber, its development and its detection technology, including the online monitoring and the offline detection technology. On this basis, the paper focused on the vacuum degree online monitoring system based on coupling capacitance.Based on the partial discharge principle, the coupling capacitance method is proposed to detect the vacuum of the vacuum interrupter under normal operation. Through the sensor we can acquire the electrical signal of the shield, and then the vacuum could be achieved by the experiment comparison, finally we can use the liquid crystal to display the result and the communication module to transfer the signal to the PC. In order to improve the measurement accuracy, I used the simulation algorithm of the wavelet change, through which the interference can be removed effectively. Experimental results show that:this method can monitor the vacuum of the vacuum interrupter effectively and real-time, providing the safe operation of the power system.This system is based on the AVR MCU, and through this core I designed the hardware system of the vacuum online monitoring system, then I used the readable C language to develop the hardware system.Finally, I have built an online monitoring system of the laboratory operating platform, and made several experiments to verify its feasibility. I have also handed the prototype to the factory and finished the installation and experimental work of the prototype. Results can be verified that the system is capable of vacuum degree online measurement.