Driving mutually coupled coils using an array of class-E amplifiers
| buir.advisor | Atalar, Ergin | |
| dc.contributor.author | Arghiani, Ziba | |
| dc.date.accessioned | 2022-09-20T09:22:34Z | |
| dc.date.available | 2022-09-20T09:22:34Z | |
| dc.date.copyright | 2022-09 | |
| dc.date.issued | 2022-09 | |
| dc.date.submitted | 2022-09-19 | |
| dc.department | Department of Electrical and Electronics Engineering | en_US |
| dc.description | Cataloged from PDF version of article. | en_US |
| dc.description | Thesis (Master's): Bilkent University, Department of Electrical and Electronics Engineering, İhsan Doğramacı Bilkent University, 2022. | en_US |
| dc.description | Includes bibliographical references (leaves 77-81). | en_US |
| dc.description.abstract | Linear radiofrequency (RF) power amplifiers are commonly used in magnetic resonance imaging (MRI) to generate radiofrequency field (B1). These low-efficiency amplifiers require cooling systems and lengthy transmission cabling, increasing the MRI hardware cost. An array of on-coil class-E amplifiers is pro-posed for the transmit system to mitigate these problems. Class-E amplifiers are switching type amplifiers capable of achieving 100% power efficiency theoretically. In this dissertation, a state-space model is proposed to simplify interpreting and analysis, and provide insight into the system of on-coil class-E amplifiers. This model can also be employed to find high power and efficiency modes of ampli-fiers’ operation. Using the state-space model, phase delays are adjusted between gate signals of the amplifiers to obtain high power and efficiency even in the presence of highly coupled coils. In addition, a sampled-data system generated from the state-space model is proposed to analyze the system’s transient behav-ior by investigating the time constant of the system. To validate the state-space model, a single class-E amplifier and two class-E amplifiers with coupled coils are simulated in LTSPICE. Moreover, novel hardware is designed for the class-E amplifier resulting in a cost-efficient design. Simulation and experimental results are provided to demonstrate the effectiveness of the proposed model. | en_US |
| dc.description.degree | M.S. | en_US |
| dc.description.statementofresponsibility | by Ziba Arghiani | en_US |
| dc.format.extent | xiv, 81 leaves : illustrations (color), charts, graphics ; 30 cm. | en_US |
| dc.identifier.itemid | B161319 | |
| dc.identifier.uri | http://hdl.handle.net/11693/110547 | |
| dc.publisher | Bilkent University | en_US |
| dc.rights | info:eu-repo/semantics/openAccess | en_US |
| dc.subject | MRI system | en_US |
| dc.subject | State-space model | en_US |
| dc.subject | Class-E amplifier | en_US |
| dc.subject | Transmit array system | en_US |
| dc.title | Driving mutually coupled coils using an array of class-E amplifiers | en_US |
| dc.title.alternative | E-sınıfı yükselteç dizisi kullanarak kuplajlı bobinlerin sürülmesi | en_US |
| dc.type | Thesis | en_US |