Mathematical analysis and experimental application of compensation schemes in magnetically coupled resonance circuits

In addition to MR imaging and some critical physics applications, magnetic resonance circuits have been used frequently in power electronics applications such as wireless power transfer systems in recent years. Wireless power transfer can be expressed as the transfer of power to the load from a high frequency power source through the air without any connection in between. The magnetic resonance technique is used at medium distances for maximum efficient power transfer. In magnetic resonance-based systems, each of coil pair consists of so-called primary and secondary coils coupled via the magnetic field. Capacitors are connected to both primary and secondary coils so as to eliminate the reactive component of the input impedance. The most common connection schemes of the compensation capacitors are series-series (SS), series-parallel (SP), parallel-parallel (PP), and parallel-series (PS). With these connection schemes, power transmission is provided with the highest efficiency. In this thesis, mathematical analyses of SS, SP, PS and PP topologies used in magnetic resonance circuits are performed. As a result of these analyses, three resonance conditions, known as single resonance and frequency separation, are deduced for SS and SP schemes. For the PS and PP compensation schemes, since very long analytical expressions are obtained and analytical solutions could not be found for certain cases, simulations are made through circuit simulation programs and resonance responses are examined. The SS compensation scheme, whose analytical expressions are extracted, is utilized in a sample magnetic passive sensor application.