Low voltage power distribution user side state assessment based on narrowband Internet of things （NB-IOT） Technology research

With the rapid development of distribution network load, users have higher requirements for power supply reliability. At present, the power supply company mainly relies on the “95598” customer service phone number dialed by users after power outages for low-voltage side power supply loop terminal status information,and cooperates with distribution network automation and power outage management systems to handle low-voltage network faults. At the same time, it is only possible to predict the location of the fall fuse or switch based on the description of the power outage user, analyze the scale of the power outage, personnel strength, and emergency repair plan, determine the priority of emergency repair, calculate the work force required on site, estimate the recovery time, and manage it field work. In troubleshooting, there are common phenomena such as incomplete fault judgment, delayed repairs, high work intensity, and high implementation costs. How to quickly, accurately and comprehensively collect the status information of the low-voltage side power supply loop is particularly important.Therefore, it is necessary to in-depth study of low-voltage user-side power supply loop status assessment and fault warning technology, and real-time grasp of the operating status information of the low-voltage side power supply loop of the distribution network.