Design and analysis of capacitive power transfer system for low power applications

• Main Author: Abdul Rahman, Farah Khalidah
• Format: Thesis
• Language: English; English
• Published: 2021
• Subjects: T Technology (General); TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://eprints.utem.edu.my/id/eprint/26016/1/Design%20and%20analysis%20of%20capacitive%20power%20transfer%20system%20for%20low%20power%20applications.pdf; http://eprints.utem.edu.my/id/eprint/26016/2/Design%20and%20analysis%20of%20capacitive%20power%20transfer%20system%20for%20low%20power%20applications.pdf; http://eprints.utem.edu.my/id/eprint/26016/; https://plh.utem.edu.my/cgi-bin/koha/opac-detail.pl?biblionumber=121113
• Institution: Universiti Teknikal Malaysia Melaka

Capacitive power transfer (CPT) system has been chosen as an alternative to perform the contactless power transfer in recent years. Advantages of CPT includes ability to confine electric field between coupling plates, power transfer capability through metal barriers, low eddy current power losses in metal surroundings, as well as the potential to minimise circuit size and costing. However, the challenge of handling CPT includes the separation distance between the transfer plates. This thesis focuses mainly on the development of a fundamental theory of CPT system and its application for low power contactless charging, starting from designing and analysing Class E resonant inverter to generating high frequency AC power source to drive the CPT system. The design is ensured to fulfil Zero-Voltage Switching (ZVS) condition in order to avoid switching loss. In electronic system, the quality factor, QL represents the effect of electrical resistance towards the system. By using Class E power amplifier circuit, the system with QL = 10 produced better results as compared to QL = 40. Considering the sensitivity of components variation, the investigation of Class E resonant inverter with π1a impedance matching circuit is done to act as a compensation network in order to enable efficient power transfer between the two parts of the system for wider load-range changes. The size of the capacitive plates was also succeeded to be reduced to half of the initial measurement by implementing the impedance matching network. The implementation of aluminium plate as transfer material for the CPT system shown the peak-to-peak value of output voltage is 25.5V with 52.55% duty cycle. After an impedance matching being inserted into the system, the experimental work produced 9.51W with 95.10% efficiency. Different materials of capacitive plates were also been investigated and discussed further in this thesis by providing the consequences of using particular materials towards the efficiency of the system. Copper has shown the best results by producing a better exponential decrease as compared to aluminium and zinc, in line graph of the output voltage.