Research And Design Of Online Energy Extracting Device On High Voltage Transmission And Distribution Line

In the overall architecture of the power grid, the high voltage transmission and distribution line plays a very important role. When it breaks down, it will have a great negative impact on the social economy and people’s life. Therefore, more and more monitoring devices are used to monitor the state of the high voltage transmission and distribution line in real time, and the stable and reliable power supply is the key to the effective running of these devices.In this paper, the existing online power supply technology is summarized. A design scheme of online energy extracting device on high voltage transmission and distribution line is introduced to solve the existing problems. This scheme combines the induction power supply with the battery power supply. In the former part, nanocrystalline core and silicon steel core are adopted in parallel. The nanocrystalline core is applied in the case of low current(from three amperes to one hundred amperes) because of its high initial permeability while the silicon steel core is applied in the case of large current(from one hundred amperes to one thousand amperes) because of its high saturation flux density. The appropriate core can be chosen according to the scope of current by designing the core switch circuit. In the later part, lithium battery which can be connected to supply power for monitoring devices when the induction power supply is insufficient is adopted.Firstly, with the basic theory of motor and electromagnetism, the principle of induction power supply is analyzed and the relationship between output voltage, current, magnetic core permeability, core size and other parameters is studied. Secondly, the simulation software Saber is introduced. With the Saber simulation, the core size and turn number of the secondary winding are determined. Finally, the overall structure diagram and circuit of the online energy extracting device are designed, and the experiment is carried out.Experimental results show that the online energy extracting device can provide stable power between three amperes and one thousand amperes with low power deadband and meet the power supply requirement of high voltage monitoring devices.