Investigation of power loss in wound toroidal cores under PWM excitation

Effects of geometrical factors on iron loss increase in wound toroidal cores energized by pulse width modulated voltage sources

“…When a typical strip wound toroidal core is energized by the PWM voltage sources additional losses occur in the laminated cores due to non-sinusoidal flux variation [4]. Limited investigations have been carried out on strip wound toroidal and stator cores which showed that core geometry has effects on power loss [5,6].…”

Design optimisation of a typical strip-wound toroidal core using genetic algorithms

“…The magnetic properties of the strip material are assessed in the Epstein Square in which short strips are stacked, magnetised and tested under well-defined standard conditions. Normally, when the material is built into a device, the final magnetic properties are poorer than when tested in the Epstein Square; however, in the toroid the material operates under better magnetic conditions [5]. The flux is mainly directed along its rolling direction, there are no corners, no air gaps exist, good annealing can eliminate harmful stress effects, and good core winding gives a high stacking factor.…”

Minimization of Losses in Converter-Fed Induction Motors – Optimal Flux Solution

“…The fast growth of the number of industrial applications using static frequency converters recently observed in variable speed drives has encouraged the meticulous study of losses in magnetic materials under PWM supply by several researchers [3,4,5,6,7,8]. They have shown that such losses depend on a number of control parameters, such as the modulation index, the number of levels and pulses of the frequency converter and the duration of PWM signal pulses.…”