Author(s):
Jyoti Shah and R. K. Kotnala

Abstract:
Electricity transmission and power conversion devices are always associated with huge power losses and transformer is the primary element in electricity transmission system and power conversion devices. Moreover, it is the major constituent of the power losses because of retaining substantial core losses which are further disintegrated into hysteresis and eddy current losses. Consequently, there is an immediate need for innovating new materials for transformer core to minimize the losses. Besides low hysteresis losses, high power to weight ratio is also a key factor for fabricating efficient and light weight transformer core. In this direction, soft magnetic nanocomposites provide attainable solution by exhibiting low hysteresis losses. In present work it is first time reporting a light weight and highly efficient polypyrrole-magnetite nanocomposite based toroidal transformer core. Polypyrrole-magnetite based nanocomposites are synthesized by facile and cost-effective solution phase route and fabricated as toroidal cores to study the power losses at high frequencies for transformer applications. Vibrating sample magnetometer (VSM) study shows the decrement in hysteresis losses from 8576 erg/cm3 for bare Fe3O4 NPs to 6467 erg/cm3 for NC- 90(90:10; Fe3O4:PPy).Core losses measurement of composites at open circuit (no-load test) reveals reduction in loss values from 43.20 mW/cm3for bare Fe3O4 NPs to 30.72 mW/cm3 for NC-90 and from 30.35 mW/cm3 to 18.24 mW/cm3at 5 V and 3.5 V excitation voltages, respectively. Moreover, similar trends are also observed in broad range of frequencies ranging from 50 Hz to 50 kHz. Minimum core loss30.72 mW/cm3at 50 kHz has been reported by NC-90 nanocomposite. Low Core losses are the primary need of hour for miniaturization of future economical transformer devices.

Pages: 317-328

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