Loose Coupling Transformer Design And Power Control For Wireless Power Transmission

Inductive Coupled Power Transfer(ICPT)technology is a new technology based on the principle of electromagnetic induction,power electronics,control theory and so on,to realize the technology of providing electrical energy for electrical equipment by means of non-electrical contact.Because of its safe,reliable,efficient,and flexible non-contact transmission of electrical energy,it has a wide range of applications in handheld electronic devices,transportation,aerospace,medical,lighting,mines and underwater applications.This paper introduces the common topology and main components of inductive wireless power transmission systems.The loosely coupled transformers for the core components of the system are analyzed and the equivalent circuit model of loosely coupled transformers is analyzed and established.The measurement of the inductive coupling coefficient of loosely coupled transformers is discussed.Based on the equivalent circuit model of loosely coupled transformer,four basic resonant compensation circuit topologies are introduced and the characteristics of the double-sided LCC resonant compensation network and its parameter design methods are analyzed.A deep discussion was made on the design of loosely coupled transformers in the system.The finite element analysis software ANSYS Maxwell is used to simulate and analyze the core and coil structure of a typical loosely coupled transformer.Based on theoretical analysis and simulation analysis,an optimization method is proposed based on its advantages and disadvantages.Finally,under the given constraint conditions,A new type of high power density loosely coupled transformer was designed.Based on the research of the main circuit and control method of the system,the closed-loop control method of the system is proposed,and the system hardware(including buck circuit,high-frequency inverter circuit,high-frequency rectifier circuit,control circuit)and software design are completed.Using ANSYS Simplorer and ANSYS Maxwell software co-simulation method,the theoretically calculated system circuit parameters were simulated and verified.Then,using the experimental platform of the built-in 3.3KW inductive wireless power transmission system,the radio energy transmission experiment under various conditions was completed.The experiment proves that the system transmission capacity is stable.When operating under the rated power,the overall system transmission efficiency reaches 93%and the system parameters are set reasonably.At the same time,the output characteristics of the current source of the bilateral LCC resonant compensation network and the influence of the change in the spatial position of the loosely coupled transformer on the system transmission efficiency are also verified,which basically accords with the theoretical analysis conclusion.