Research On Magnetically Coupled Resonance Wireless Power Transfer System Based On LCC-series Resonant Topology

With the increasing progress of science and technology and the continuous improvement of economic,the world's energy situation also has undergone unprecedented changes.The proportion of electricity in energy consumption is increasing.Compared with the wired power transfer mode,the advantages of the wireless power transfer technology make it become the current research hotspot.Magnetically coupled resonance wireless power transfer technology can be used for wireless charging of electric vehicles,and has wide application value,because of its many advantages,for instance,high transfer efficiency and large transfer power in medium transmitting distance,good robustness and suitable for special environment.Currently,there are some research results in this field,but it is still a long distance from the practical application.Some key problems that have not yet been solved,which need to be researched.In this paper,several kinds of wireless power transfer technology are introduced,and their basic structure,transmission principle and development status are briefly explained.Then,the basic coupling principle and the present research situation of the magnetically coupled resonance wireless power transfer technology are illustrated.Also,this paper indicating that the resonant topology has a closely influence on the wireless power transmission system.Then,the model of the wireless power transmission system which used series-series resonant topology is established based on circuit theory,and its transmission characteristics are analyzed.It is found that the transfer power is not large under the condition of small load resistance,and it is not suitable for the electric vehicle wireless charging system.And then the wireless power transmission system which used LCC-series resonant topology is proposed,its model is established based on circuit theory alternating current impedance analysis method.Its transmission characteristics are analyzed and it is found that the system which used LCC-series resonant topology has a constant voltage output characteristic.It is found that the transfer power can be large under the condition of small load resistance,and it is suitable for the electric vehicle wireless charging system.Then,this paper analyzes the resonant coil which is the core components of the magnetically coupled resonance wireless power transmission system.When the parameters of the resonant coil change,the trend of the resonant coil self-inductance,mutual inductance and coupling coefficient is simulated by the finite element simulation analysis method.And the design principle of resonant coil is summarized.Finally,the hardware circuit is designed,and the hardware platform of the magnetically coupled resonance wireless power transmission system which used LCC-series resonant topology is established.The transmission characteristics are verified by experiments.Experiments show that the hardware experimental platform can realize wireless transmission of power.In the 85kHz operating frequency,8cm transmission distance,100? load resistance,the system achieved the transmission efficiency of 95.23%.The experiment also analyzes the transmission characteristics of the hardware experimental platform,which is in good agreement with the result of theoretical analysis.