Visible to the public Exciter Remanence Effect Mitigation in a Brushless Synchronous Generator for Test-field Applications

TitleExciter Remanence Effect Mitigation in a Brushless Synchronous Generator for Test-field Applications
Publication TypeConference Paper
Year of Publication2021
AuthorsWredfors, Antti, Korhonen, Juhamatti, Pyrhönen, Juha, Niemelä, Markku, Silventoinen, Pertti
Conference NameIECON 2021 – 47th Annual Conference of the IEEE Industrial Electronics Society
Keywordscomposability, compositionality, Current control, Generators, insulated gate bipolar transistors, Magnetic Remanence, Power measurement, pubcrawl, resilience, Resiliency, synchronous generators, Topology, Voltage control, Windings
AbstractBrushless synchronous generators (BSG) are typically used to produce an island network whose voltage is close to the nominal voltage of the generator. Generators are often used also in test-field applications where also zero output voltage is needed. The exciter construction and magnetic remanence may lead to a situation where the non-loaded generator terminal voltage cannot be controlled close to zero but a significant voltage is always generated because the exciter remanence. A new brushless synchronous generator excitation and de-excitation converter topology for test applications is proposed. The purpose is to achieve full voltage control from zero to nominal level without modifications to the generator. Insulated-gate bipolar transistor (IGBT) and Field-Programmable Gate Array (FPGA) technology are used to achieve the required fast and accurate control. In the work, simulation models were first derived to characterize the control performance. The proposed converter topology was then verified with the simulation model and tested empirically with a 400 kVA brushless synchronous generator. The results indicate that the exciter remanence and self-excitation can be controlled through the exciter stationary field winding when the proposed converter topology controls the field winding current. Consequently, in highly dynamical situations, the system is unaffected by mechanical stresses and wear in the generator.
DOI10.1109/IECON48115.2021.9589654
Citation Keywredfors_exciter_2021