Research On Design And Control Strategy Of Dynamic Cluster Wireless Charging System For Electric Vehicle

The proposal of the goal of "carbon peak and carbon neutrality" has accelerated the pace of the energy revolution,and the characteristics of clean energy production and electrification of energy consumption will become more obvious.Electric vehicles are receiving more and more attention due to their high energy efficiency and low polluting gas emissions.The current wired charging method has certain difficulties in meeting the demands of unmanned and intelligent.As a new type of charging method,dynamic wireless charging technology realizes the "charging while walking" without actual electrical connection between the piles.This method can use the existing right of way to realize the online energy replenishment of electric vehicles and overcome the shortcomings of wired charging.Alleviating the problem of battery life of electric vehicles.At present,the research of dynamic wireless charging system concentrates on theoretical research,and the design of its hardware system is less involved.Therefore,based on the principle of dynamic wireless charging and transmission,the paper carries out dynamic wireless charging system design,modeling and analysis of road load,and carrying out charging strategy research to promote the development of dynamic wireless charging technology and contribute to the construction of a green and low-carbon society.Based on the engineering of the short-track dynamic wireless charging system,this thesis studies the principle of dynamic wireless charging of the short-track electric vehicle,carries out the hardware design simulation of the dynamic wireless charging system,and proposes shortsegmented transmitting coils switching strategy.Further more,Clustered load forecasting and vehicle charging strategy is also addressed in the thesis.The main work is as follows:(1)Combined with the principle of magnetic coupling resonance,the analysis and modeling of the transmission characteristics of the short-track dynamic wireless charging system with multiple transmitting coils are mainly focused on the research of the dynamic wireless charging principle.Using the principle of dynamic wireless charging for electric vehicles with short tracks,the transmission characteristics of single transmitter coils,double transmitter coils and even multiple transmitter coils are analyzed,and LCC-S(InductanceCapacitor-Capacitor-Series)compensation topology is selected for the transmitter coil.The connection mode is compared,and the conclusion is drawn that the current is controllable when the system adopts the parallel connection mode,so the parallel connection mode is selected.Through simulation and comparison,the mutual inductance of closely adjacent coils in the dynamic wireless charging system is analyzed,and the simulation results are substituted into the current calculation formula for simplification to calculate the overall system loss and system efficiency of the cluster dynamic charging.(2)The design of the dynamic charging system of electric vehicles and the short-track transmitting coils switching strategy is studied.The thesis builds the overall framework of the dynamic charging system,and design and select the power distribution part and power supply part of the system according to the existing wireless charging international standards.Three possible dynamic wireless charging power distribution methods are simulated and verified to find out the applicable scope of various power distribution schemes.The thesis analyzes the principle of mutual inductance and power fluctuation between dynamic wireless charging coils,calculated the mutual inductance between coils under different conditions.The switching method of "theoretical switching point" and "actual switching point" is proposed: the switching method of "theoretical switching point" is adopted when the vehicle speed is low and the switching accuracy is high,and the switching method of "actual switching point" is adopted when the vehicle speed is high and the switching accuracy is low.The switching strategy was verified experimentally,and the problem of power fluctuation caused by switching the transmitting coil was solved.(3)To study the dynamic charging road charging strategy clustering and multi-vehicle load forecasting,research focused on the engineering application point Dynamic wireless charging system exploration.Analyzed the influencing factors of single-vehicle and cluster-type electric vehicle charging,and carried out modeling and analysis around the two main factors of dynamic wireless charging,vehicle flow and charging power.The hybrid neural network based on wavelet and BP neural network was used for electric vehicles.Traffic forecasting,clustering the charging power of electric vehicles entering the road section according to vehicle type,battery capacity,and remaining SOC,combined with Monte Carlo simulation method to predict the daily load of dynamic charging roads,and separately predicting the traffic conditions when there are few cars and many cars A charging control strategy for small electric vehicles based on vehicle speed is proposed,and a rapid charging strategy for engineering is discussed based on the existing power level restrictions.