Research On Electric Field Coupling Wireless Power Supply System For High Voltage Side Equipment

With the rapid development of the national power industry,the process of intelligent power system is gradually advancing,a large number of intelligent high-voltage side equipment has been put into application,to ensure its stable operation,especially the stable power supply is of great significance to the safety and reliability of the power system.The traditional power supply methods,such as lithium battery power supply and new energy power generation,have the disadvantages of cumbersome power exchange work and easy to be affected by the surrounding environment,which can not adapt to the intelligent process of power system.In recent years,with the development of wireless power transmission technology,this power supply mode has gradually entered every corner of our life.Compared with the traditional wire connection power supply mode,it can transmit electric energy without direct contact of conductor,which naturally solves the problem that it is difficult to cross high and low potential under the condition of ensuring insulation when supplying power to high voltage side equipment,and provides a new solution for power supply of high voltage side equipment.Aiming at the power supply problem of high-voltage side equipment in smart grid,this paper proposes a scheme of using electric field coupled radio power transmission to supply power for high-voltage side equipment,and carries out relevant design,simulation and experiment of radio power transmission system.The overall architecture of wireless power supply system for high voltage side equipment is introduced.Combined with the structure of high voltage side and the basic principle of electric field coupling wireless power transmission,the design of electric field coupling wireless power supply system suitable for high voltage side and the demand of power supply for the system are proposed.For the designed wireless power supply system,the calculation and analysis are carried out when the RF power supply acts alone and the power frequency electric field acts alone.The influence of RF electric field on the original power frequency electric field is simulated.The RF circuit of the transmission system is simulated,and the transmission characteristics are analyzed when the load impedance and coupling capacitance are different.The transmission efficiency of the physical model of the system is simulated,and the influence of different transmission distance and different dielectric loss on efficiency is analyzed.According to the requirements of power supply for wireless power transmission system,the realization mode of RF power supply with signal source and power amplifier is selected and realized,and the impedance matching network and load detection circuit are designed to improve the power efficiency.The experiment platform is built to complete the experiment of radio power transmission.This paper mainly studies the power supply of high voltage side equipment by electric field coupled wireless power transmission,and proposes a wireless power transmission scheme combining insulator and coupling mechanism.The calculation shows that the scheme can obtain stable voltage output and is not affected by power frequency high voltage.The simulation results show that the introduction of RF power supply will not affect the insulation,and the system can work stably and efficiently when the load and coupling capacitance change.It is confirmed that the dielectric loss and leakage field when the transmission distance is too long will reduce the efficiency.Experiments show that the transmission system can output stably for different sizes of loads,and the maximum efficiency can maintain more than 25%when the output power is more than 7W.