{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/10431"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/10431","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"Medium voltage petrochemical drives : soft start and adjustable speed systems","abstract":"Medium voltage synchronous machines are used for large petrochemical compressor motor drives (>13 MW) at high application voltages (e.g. +-11 kV). Limited research exists on the application of Voltage Source Inverters (VSIs) for these petrochemical loads. An application concept is described where the converter is used to start several motors and to drive one at adjustable speed. Associated benefits in terms of availability, hazardous areas and switching surge overvoltages are outlined. A technology feasibility study illustrates that new VSI Cascaded H Bridge (CHB) technology and the application concept is economically feasible. Ultimately the research illustrates how and where new VSI technology can economically be applied with a significantly lower risk level.","abstract_html":"Medium voltage synchronous machines are used for large petrochemical compressor motor drives (>13 MW) at high application voltages (e.g. +-11 kV). Limited research exists on the application of Voltage Source Inverters (VSIs) for these petrochemical loads. An application concept is described where the converter is used to start several motors and to drive one at adjustable speed. Associated benefits in terms of availability, hazardous areas and switching surge overvoltages are outlined. A technology feasibility study illustrates that new VSI Cascaded H Bridge (CHB) technology and the application concept is economically feasible. Ultimately the research illustrates how and where new VSI technology can economically be applied with a significantly lower risk level.","abstract_has_math":false,"creators":["Endrejat, Frieder"],"institution":"Department of Electrical Engineering","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Pillay, Pragasen"],"committee_chairs":[],"committee_members":[],"year":2010,"date_issued":"2010","date_published":"2010","updated_at":"2026-07-22T22:23:19Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/10431","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Pillay, Pragasen"]},{"key":"dc:creator","label":"Author","values":["Endrejat, Frieder"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-12-28T20:04:30Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-12-28T20:04:30Z"]},{"key":"dc:date.issued","label":"Date","values":["2010"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Electrical Engineering"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["PhD"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/10431"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Includes bibliographical references."]},{"key":"dc:description.abstract","label":"Abstract","values":["Medium voltage synchronous machines are used for large petrochemical compressor motor drives (>13 MW) at high application voltages (e.g. +-11 kV). Limited research exists on the application of Voltage Source Inverters (VSIs) for these petrochemical loads. An application concept is described where the converter is used to start several motors and to drive one at adjustable speed. Associated benefits in terms of availability, hazardous areas and switching surge overvoltages are outlined. A technology feasibility study illustrates that new VSI Cascaded H Bridge (CHB) technology and the application concept is economically feasible. Ultimately the research illustrates how and where new VSI technology can economically be applied with a significantly lower risk level."]},{"key":"dc:title","label":"Title","values":["Medium voltage petrochemical drives : soft start and adjustable speed systems"]}]}],"canonical_facts":{"dc:contributor.advisor":["Pillay, Pragasen"],"dc:creator":["Endrejat, Frieder"],"dc:date.accessioned":["2014-12-28T20:04:30Z"],"dc:date.available":["2014-12-28T20:04:30Z"],"dc:date.issued":["2010"],"dc:description":["Includes bibliographical references."],"dc:description.abstract":["Medium voltage synchronous machines are used for large petrochemical compressor motor drives (>13 MW) at high application voltages (e.g. +-11 kV). Limited research exists on the application of Voltage Source Inverters (VSIs) for these petrochemical loads. An application concept is described where the converter is used to start several motors and to drive one at adjustable speed. Associated benefits in terms of availability, hazardous areas and switching surge overvoltages are outlined. A technology feasibility study illustrates that new VSI Cascaded H Bridge (CHB) technology and the application concept is economically feasible. Ultimately the research illustrates how and where new VSI technology can economically be applied with a significantly lower risk level."],"dc:identifier.uri":["http://hdl.handle.net/11427/10431"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Electrical Engineering"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["Medium voltage petrochemical drives : soft start and adjustable speed systems"],"dc:type":["Doctoral Thesis"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["PhD"]},"updated_at":"2026-07-22T22:23:19Z"}