This paper proposes an online condition monitoring system for aluminum electrolytic capacitors used as dc-link capacitors in industrial power converters. Electrolytic capacitors are one of the most fragile components of a power converter system because of their wear-out failures and short lifespan. Therefore, the use of condition monitoring systems for aluminum electrolytic capacitors allow preventive maintenance to be performed, thereby avoiding unexpected shutdown and downtime. The dominant wear-out mechanisms in aluminum electrolytic capacitors are characterized by the increase in equivalent series resistance. Hence, the condition monitoring system proposed in this paper is based on the online estimation of the capacitor's equivalent series resistance using the switching frequency components of the dc-link capacitor voltage and current. The equivalent series resistance estimation method is tested using the PSpice circuit simulator and is validated experimentally using a custom-made inverter. Finally, the equivalent series resistance estimation method is adapted for the condition monitoring of capacitors in industrial power converters and the proposed condition monitoring system is implemented in a commercial ac drive system to prove the applicability of the proposed method to industrial power converters.
The magnetic component is considered one of the major factors that dominate the power density of power converters. In this paper, magnetic integration of inductors of a three-phase LCL filter on delta yoke composite core is explored and investigated. Using the conventional rectangular core as the baseline design reference, the proposed delta yoke core achieved a weight reduction of close to 10% without affecting the filter's performance.
The inductances based on both shapes were calculated and verified through magnetic circuit analysis and 3-D finite element analysis (FEA) simulation. Hardware prototypes of the integrated inductor with both the conventional rectangular and the proposed delta yoke cores were fabricated and tested with a three-phase inverter circuit to verify the design validity.Index Terms --Delta yoke core; Magnetic integration; LCL filter; High power density converter
I.Rejeki Simanjorang (SM'16) was born in Tanah Karo, Indonesia. He received his B.Sc., M.Eng. and Dr.Eng. degrees in Electrical
This paper presents the power density developments of high-power isolated dc-dc converter to be utilized in a higher voltage direct-current (HVDC) powersupply system of a data center. This technique results in a prototype of dc-dc converter unit which is smaller by factor of ten when compared with the conventional one, and the area of power-supply system becomes much smaller than before. Consequently, the cooling power for this power-supply system is saved and both the energy and the space saving are available.In order to realize a prototype of the high-power isolated dcdc converter, the switching power devices composed of a hybrid pair of Si-CoolMOS and SiC-SBD are utilized and operated in a driving pattern of hard switching with a frequency of 200kHz. As a result, an isolated dc-dc converter with the input/output voltage of 400V/400V, a rating power of 5kW, and a high power density of 10W/cm 3 has been fabricated. The experimental confirmation was reported and the surge problems due to diode recovery difficulties mentioned before was solved.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.