A facile approach to prepare a flexible and durable electrically driven cotton fabric-based heater

Flexible and durable electrically driven heaters (EDHs) was prepared by using silver nanowire/polydopamine modified cotton fabric (AgNW/PDA-C) as Joule heat generator and polydimethylsiloxane (PDMS) as stretchable matrix.The electric property of the EDHs was investigated, and it can show excellent electrical property and stability. The EDHs can be seen from the SEM morphology that cotton fabric was well protected by the PDMS and has good conductive network. The EDHs also exhibit excellent electrothermal performance under applied voltage. At low-voltages, it can quickly reach satisfactory steady-state temperatures that meet the needs of wearables. By improving the electrothermal model, it can be verified that there is a quadratic function relationship between electric power and steady-state temperature. Under cyclic voltage and bending tests, the EDHs can well maintain steady-state temperature and exhibit excellent dynamic and static electrothermal performance.

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Identification of DC Thermal Steady-State Differential Inductance of Ferrite Power Inductors

Energies ◽

10.3390/en14133854 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3854

Author(s):

Salvatore Musumeci ◽

Luigi Solimene ◽

Carlo Stefano Ragusa

Keyword(s):

Steady State ◽

Input Voltage ◽

Switching Frequency ◽

Ohmic Losses ◽

Steady State Temperature ◽

Wide Range ◽

Average Current ◽

Power Inductors ◽

Saturable Inductor ◽

Thermal Steady State

In this paper, we propose a method for the identification of the differential inductance of saturable ferrite inductors adopted in DC–DC converters, considering the influence of the operating temperature. The inductor temperature rise is caused mainly by its losses, neglecting the heating contribution by the other components forming the converter layout. When the ohmic losses caused by the average current represent the principal portion of the inductor power losses, the steady-state temperature of the component can be related to the average current value. Under this assumption, usual for saturable inductors in DC–DC converters, the presented experimental setup and characterization method allow identifying a DC thermal steady-state differential inductance profile of a ferrite inductor. The curve is obtained from experimental measurements of the inductor voltage and current waveforms, at different average current values, that lead the component to operate from the linear region of the magnetization curve up to the saturation. The obtained inductance profile can be adopted to simulate the current waveform of a saturable inductor in a DC–DC converter, providing accurate results under a wide range of switching frequency, input voltage, duty cycle, and output current values.

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Heterogeneous Preparation of Cellulose/Ag/Polyaniline Conductive Composite and its Electrical Property

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.182-183.254 ◽

2012 ◽

Vol 182-183 ◽

pp. 254-258

Author(s):

Zhong Li Zhao ◽

Zun Li Mo ◽

Zhong Yu Chen

Keyword(s):

Electrical Conductivity ◽

Electrical Property ◽

Conductive Network ◽

High Electrical Conductivity ◽

Electrically Conductive ◽

Conductive Composite

Cellulose/Ag/polyaniline conductive composite with rather excellent electrical conductivity was heterogeneously synthesized in this paper. The UV-Vis analysis indicated that homogeneous nanoAg particles deposited on the surface of cellulose in the form of globe particles. They offered some electrons to polyaniline chains. This behavior resulted to the facts that more polyaniline embedded on cellulose and an integrated electrically conductive network formed. Consequently, the high electrical conductivity of the composite was observed. The value was 3.48 S/cm, which was higher two magnitudes than the electrical conductivity of cellulose/polyaniline composite (2.15×10-2S/cm), and even was higher than the electrical conductivity of pure polyaniline (0.142 S/cm). This paper provided a facile method for the preparation of cellulose/Ag/ polyaniline composite with favorable electrical conductivity.

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