creator Thiakos, Dimitrios advisor Krishnamurthy, Mahesh Progress has made over the last several years in developing cleaner, more fuel-efficient vehicles. In particular, hybrid electric vehicles (HEVs) have helped reduce fuel emissions by using electrical power to power the vehicle. HEVs have been enhanced by the use of hybrid-energy-storage-systems (HESS), which use an ultracapacitor to satisfy peak-power demands, thereby increasing the life of the battery. In this paper, dynamic models of the individual components of a HEV are created from dynamic equations, and then implemented in Simulink. The components include a realistic battery, an ultracapacitor, and a Permanent Magnet Synchronous Motor. The models are simulated, and the results serve as a basis for how these components should behave. Next, the various power management and control algorithms of a HESS are presented. Then, several HESS topologies are modeled in PSIM, which is a simulation tool for power electronics and motor drives. Simulation results for a simple drive-cycle are presented, and the pros and cons of each topology are described. Considerations are given as to the topologies with the best combination of performance, cost, and life cycle. Furthermore, the benefits of using a HESS in terms of cost, volume, weight, and efficiency, are explained in more detail. Finally, some limitations of PSIM that affected simulation results are explained. Overall, this thesis lays out the various factors that affect choices in HESS topologies. Submitted by Liana Khananashvili (khananashvili@iit.edu) on 2014-10-24T18:48:35Z No. of bitstreams: 2 DNT_final_thesis_iitstyle_no_sig.pdf: 15833523 bytes, checksum: 02e6101ab12e428a71cab20cfe0fc0b8 (MD5) signed_cover_sheet.PDF: 18847 bytes, checksum: 1de04c4c915f078ffd70802b7139ef65 (MD5) Made available in DSpace on 2014-10-24T18:48:35Z (GMT). No. of bitstreams: 2 DNT_final_thesis_iitstyle_no_sig.pdf: 15833523 bytes, checksum: 02e6101ab12e428a71cab20cfe0fc0b8 (MD5) signed_cover_sheet.PDF: 18847 bytes, checksum: 1de04c4c915f078ffd70802b7139ef65 (MD5) Previous issue date: 2014-05 M.S. in Electrical Engineering, May 2014 2014 2014-05 http://hdl.handle.net/10560/3312 en Thesis born digital application/pdf In Copyright http://rightsstatements.org/page/InC/1.0/ Restricted Access ECE / Electrical and Computer Engineering Illinois Institute of Technology Affiliated department