Although the technology of integrated passives in power electronics has been receiving a lot of attention recently, behavior prediction of these integrated passive structures is still not on an acceptable level for widespread applications. A lot of work has been done recently on accurate electromagnetic modelling of these structures, but the complex models investigated are not practical for the average engineer in power electronics to apply, and integrated passives remain a subject of interest in research and academia, but very infrequently applied in industry. The aim of this dissertaion is to provide a bridge between the mathematical models currently being investigated, and circuit level behaviour prediction which may be used by practicing engineers to design power electronics circuits which make use of integrated passives. The history of integrated passives is first investigated, along with historical modelling techniques and their shortcomings. Two similar modern distributed circuit theory models are investigated and aspects of both are combined to form the model that is used as a mathematical foundation for this dissertation. This model is analysed, and some methods are proposed for integrating the resulting differential equations. A transformation is proposed for transforming the transmission network representa- tion of the structure, which results from integrating the differential equations, into a network of admittances, which may be used for applying the technique of nodal analysis to a circuit containing an integrated passive structure. This admittance network model is used to implement a frequency domain simulation model in a practical circuit simulator. i In the integration of the circuit differential equations, the method of modal analysis is applied. In this analysis a system of wave equations is derived and solved in the frequency domain. By applying the inverse fourier transform to these wave solutions it is found that the modal wave propogation is a simple time shift in the time domain for each propogating mode in lossless structures. Applying this observation a transient model is implemented in the circuit simulator for lossless integrated passive structures. Although this is limited to the lossless case, the simulator still appears to be giving good results. The zero voltage switching two inductor boost converter was then investigated to construct a case study for the simulator. The topology was analysed, and a design method found. A discrete converter was constucted to verify the analysis. The design of an integrated passive structure for this converter is then presented, and the simulation results show that the simulator may is robust enough to be applied to practical problems. The integrated converter could unfortunately not be constructed due to materials processing limitations, and thus the simulation result remain to be experimentally verified. The results do however closely match those predicted by the widely used lumped element models, apart from some high order effects. / Prof. I.W. Hofsajer
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uj/uj:2719 |
| Date | 12 June 2008 |
| Creators | McMullin, Gareth |
| Source Sets | South African National ETD Portal |
| Detected Language | English |
| Type | Thesis |
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