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Studies of voltage-induced deflections in electroactive paper (EAPap) have been carried out. On the experimental side, measurements of bias-dependent deflections and strain, water absorption as a function of time, and relative humidity were obtained for the cellulose EAPap actuator. In addition, model simulations have also been carried out to probe and quantify the role of the various internal mechanisms responsible for the deflection. Our simulation predictions yield good agreement with the measured deflection data for the EAPap. The modeling suggests that internal ion content and its migration, water absorption leading to a nonuniform permittivity, random variations in the transverse piezoelectric-coupling coefficient d31,i, and the modulus of elasticity all collectively contribute to the EAPap deflection electrophysics. It also appears that higher sensitivity, with a minimal bias dependence, could be achieved by deliberately adding ions during EAPap processing.

A typical set of partial discharges (PD) occurring in insulation systems can be characterized by a three dimensional plot of their phase 'φ' on the power line cycle, apparent charge magnitude 'q' and the number of pulses 'n'. A digital acquisition system is being developed which can measure 'φ' and 'q' values of 'n' PD's occurring on a given power line voltage and then plot n(φ,q). The system is developed using the data acquisition card NI-5112, which is a 2-channel high speed digitizer (100 MS/s) with the acquisition and analyses programs written in LabVIEW 8.2. The system is being tested using artificially generated PD pulses which have variable 'φ' and 'q' magnitudes and their performance benchmarked by comparing the resulting plots with the plots obtained by processing the same data on existing PD analyses system called TECHIMP-PD check.

The effect of droplets on the surface of the overhead insulators (porcelain and silicone rubber) and their contributions to electric field distribution and hence possibility of failure is investigated. Initially the variation of electric field distribution around a typical water droplet in the sheath and shed regions as a function of contact angle is investigated. The effect on field distribution in presence of multiple droplets is explored by varying the number, the relative positioning and contact angle.

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