Dissipation Factor Values Research Articles

Understanding Heat Dissipation Factors for Fixed‐Tilt and Single‐Axis Tracked Open‐Rack Photovoltaic Modules: Experimental Insights

ABSTRACTThis paper presents the results of long‐term experiments conducted on fixed‐tilt (FT) and single‐axis tracked (SAT) open‐rack photovoltaic (PV) modules in South Africa. Utilising Faiman's heat dissipation model and data filtering method, the study demonstrates favourable comparisons of FT experimental results with literature while yielding novel heat dissipation factors for SAT modules. Enhanced heat dissipation is observed in no/low wind conditions for SAT modules compared to FT modules. Analyses reveal the influence of plane‐of‐array (POA) irradiance, wind speed and direction on module temperature, with SAT modules exhibiting greater heat dissipation stability. An investigation into data filtering methods suggests minor sensitivity for both configurations, with a slightly more pronounced impact on SAT modules. Assessments comparing module temperature predictions using diverse heat dissipation factors for FT modules reveal negligible sensitivity. This suggests that exact heat dissipation factor values may not be crucial for accurate predictions of module temperature in FT open‐rack systems. Annual power output simulations using PVsyst software demonstrate a 2.9% and 3.3% enhancement for FT and SAT configurations, respectively, when employing experimentally determined heat dissipation factors. These findings highlight the importance of realistic, configuration‐specific heat dissipation factors in optimising PV system performance, particularly in the competitive context of modern PV power plant construction and techno‐economic calculations.

Zinc Oxide Filler Effect on Dissipation Factor of High-Density Polyethylene

Polymer Nano-composites (PNC) are efficient materials that consist of polymer matrix and nanoparticles to create a new generation with excellent properties. In this paper a PNC filler-based Zinc oxide (ZnO) is used for enhancing the dissipation factor (DF) or Tan δ of the obtained polymer compared to the individual polymer material and improving the electrical properties of high-density polyethylene (HDPE). The electrical properties of HDPE are investigated under different concentrations of zinc oxide including (0, 10, 20, 30, and 40 wt.%) as well as under different conditions including the variations of temperature (25-150 Celsius) and frequencies (0.1 kHz to 1 MHz). The simulation results reveal that inclusion Zinc oxide as filler can improve the electrical properties of HDPE. In addition to that the minimum value of dissipation factor and the best electrical properties can be obtained at concentration 10 % loading compared to the other concentration levels. Curve fitting solutions were performed to determine the best fit for the experimental results. African Vultures Optimization Algorithm (AVOA) was used to determine the optimal value of zinc oxide filler percentage to obtain the best optimal value of dissipation factor.

Thermal deformation behavior investigation of Ti–10V–5Al-2.5fe-0.1B titanium alloy based on phenomenological constitutive models and a machine learning method

The two-phase titanium alloy Ti–10 V–5Al-2.5Fe-0.1 B was taken as the experimental material, and thermal compression experiments were carried out at a deformation temperature of 770–920 °C and a strain rate of 0.0005–0.5 s−1. An Arrhenius model, a modified Johnson-Cook model, and an improved BP neural network model based on the sparrow search algorithm (SSA-BP) model were established to predict the high temperature rheological stress of the alloy. A comparison of the prediction accuracy of the three models was made. When the partial random data in the rheological curves was used for model building and relatively independent data were used for predicting the rheological stress, the SSA-BP model had higher prediction accuracy, which exhibits the highest mean square correlation coefficient (R2) value of 0.9992 and the lowest root mean square error (RMSE) and average absolute relative error (AARE) values of 1.3031, and 2.0947 %, respectively. The ability of three models to predict the rheological stress for the new process parameters was verified. Results show that the SSA-BP model still has better prediction ability, which exhibits the highest mean square correlation coefficient (R2) value of 0.9720 and the lowest root mean square error (RMSE) and average absolute relative error (AARE) values of 5.0099, and 6.0382 %, respectively. The predicted values of SSA-BP for the rheological stress were used to construct the hot processing map. Results show that the trend of the power dissipation factor (η) value from the hot processing map predicted by SSA-BP can well agree with the microstructure evolution of the alloy.

Co-precipitation method followed by ultrafast sonochemical synthesis of aluminium doped M type BaFe11.4-xAlxCo0.6O19 hexaferrites for various applications

The co-precipitation method followed by Sonochemical process was used to synthesize M-type BaFe11.4-xAlxCo0.6O19 hexaferrites (x = 0.0, 0.4, 0.8, 1.2, and 1.6) with Al3+ substitutions. XRD, FTIR, UV–vis spectroscopy, VSM, SEM and LCR meter are used for the characterizations of the synthesized materials. The optical properties, magnetic properties, structural, morphological, and dielectric properties had been systematically investigated. XRD data and cell refinement study confirmed the hexagonal crystal structure of the synthesized materials that belong to space-group of P63/MMC-(No 194). The values of lattice parameters ‘a’ and ‘c’ have been reduced from their original value 5.9145 Åto 5.8446 Åand 23.239 Åto 23.1684 Åcorrespondingly with doping content. The values of ratio c/a are found within 3.9292 to 3.9641 range, which can be regarded as optimal values for M-type hexaferrites structure as mentioned in previous studies. The crystallite size-(D) and volume-(V) decreases with doping concentration. The band gap of the synthesized materials had shown decreasing trend with doping content. The values of dissipation factor, dielectric loss ε'', and dielectric constant ε', are higher at lower frequency but get smaller as frequency increases. The dissipation factor, dielectric loss ε'', and dielectric constant ε', reduced as the concentration of aluminium is increased. From the analysis of M−H loops it has been concluded that saturation magnetization and remnant magnetization is decreasing with aluminium content, while coercivity is increasing. The anisotropy parameter (B) and anisotropy field (Ha) had shown increasing trend with aluminium concentration. FTIR analysis showed the development of barium hexaferrites in two main absorption-bands, the enormous frequency-band and the low frequency-band. The position of these bands were moved towards a lower frequency range with increasing Al substitution level. The reduction in band gap as well as the enhancement in magnetic and dielectric properties of barium M type hexa-ferrites as a result of aluminium doping making them suitable for various applications, including magnetic storage media, magnetic sensors, microwave devices, electromagnetic wave absorbers and permanent magnets etc.

Synthesis of flower like microstructured CdZnS films for optoelectronic applications by powder vapor transport technique

Cadmium zinc sulfide (CdZnS) is a remarkable semiconducting material used as window layer in solar cells. Herein, the flower’s like microstructured CdZnS film is synthesized by powder vapor transport (PVT) technique. The structural parameters like lattice constant, various diffraction planes, crystallinity, preferential orientation factor and standard deviation of CdZnS film of good quality growing preferentially along (110) orientations. The growth of longitudinal optical phonons modes at 303 and 599 cm−1 confirms the synthesis of CdZnS film. The values of transmittance and refractive index are ranged from 89.9%–95.2% and 1.53–2.67 whereas the values of energy band gap, oscillator energy and dispersion energy are found to be 2.79, 0.73 and 1.73 eV respectively. The values of dielectric constant are increased with increasing photon energy. The smaller values of dissipation factor and volume/surface energy loss functions of CdZnS film is suitable to make it a good quality capacitor. The electrical conductivity (1.68×103 S cm −1 ) of CdZnS film is increased nonlinearly with increasing temperature and the activation energy is found to be 0.31 eV. It is determined that the synthesized CdZnS film may be used as window layer in solar cells and to make good quality capacitor, hence it may be used in optoelectronic applications.

Comparison of exergy and exergy economic evaluation of different geothermal cogeneration systems for optimal waste energy recovery

Since energy sources are limited, any activity aimed at recycling energy waste or facilitating energy conversion systems is invaluable. Against this background, most scientists focus on the integration of energy systems and the coupling of different technologies. In this study, a variety of power systems are investigated for optimal power conversion configurations of geothermal sources. Three configurations, Organic Rankine Cycle Geothermal Cooling (GPR/ORC), Kalina Cycle Geothermal Cooling (GPR/Kalina), and Rankine Cycle and Feed water Heater (GPR/FWH) Geothermal Cooling, are classified according to exergy and Study energy economic analysis. Calculations show that the GPR/FWH system has the highest net output power of 2963 kW. In addition, the GPR/Kalina system has the lowest output power and lowest energy efficiency among the systems launched. Across the three proposed systems, the fuel cell generates 1254 kW of electricity, while the Kalina cycle in the GPR/Kalina system generates 487 kW. Exergy studies show that the GPR/Kalina and GPR/FWH systems have the lowest and highest irreversibility (3795.4 kW and 4365.56 kW, respectively). Furthermore, the fuel cell was found to have the greatest exergy destruction rate among the three configurations. The results of the economic analysis show that the fuel cell has the highest cost ratio among all designs. In addition, the values of the dissipation factor show that the absorption chiller has the highest dissipation factor value among the three configurations. Furthermore, the comparative parametric analysis provides new aspects to introduce into the system.

Dielectric frequency response at different voltage levels of mineral oil-based silica nanofluids

In this paper, the Frequency domain dielectric response of oil-paper insulation, employing SiO 2 -based nanofluids is reported. It is a well-known fact that the dissipation factor ( tanδ) profile is affected by the magnitude of excitation voltage & measurement temperature. Analysis of data obtained from laboratory samples suggests that the influence of excitation voltage is non-linear in nature. It is further observed that the degree of non-linearity is different for new and aged mineral oil. The frequency domain dielectric response for new mineral oil-based silica nanofluid has been found non-linearity nature at 50 Hz for sinusoidal excitation level 26 V-130 V for temperature range 50⁰C-70⁰C. Similarly, in the case of aged mineral oil, a non-linearity nature has been found at 1 Hz. The related analysis presented in this paper suggests that it is possible to express the non-linearity introduced in the value of dissipation factor ( tanδ) at power frequency by a mathematical expression.

Enhancing Dielectric and Thermal Performances of Synthetic-Ester Insulating Oil via Blending With Natural Ester

Synthetic ester and blended insulating oils have attracted widespread attention owing to their great potential on performance enhancement because of the high capacity with tailorable molecular structure and mixable components. In this work, natural ester insulating oil (FR3) is blended into the synthetic tetra-ester insulating oil (KA) via mixing and oscillating. The physicochemical and electrical property measurements of the ester blends indicate the flash point, fire point, and AC breakdown voltage of KA are capable to be increased, and the dissipation factor of KA is reduceable by the addition of FR3. As expected, a series of physicochemical properties of the ester blends follow a quasi-linear relationship with the variation (in vol%) of FR3. However, the flash point (closed cup) is verified with high nonlinearity according to the results of thermogravimetric-derivative and thermogravimetric-differential scanning calorimetry (TG-DSC) tests in nitrogen. The optimized ester blend (85 vol% (KA):15 vol% (FR3)) is typically manifested by high flash point (260°C), low pour point (-51°C), low dissipation factor (1.44%), high AC breakdown voltage (76.5 kV), and high onset temperature of DSC either in nitrogen (229.99°C) or in the air (272.05°C). The activation energy is analyzed based on the Arrhenius equation, dissipation factor, and resistivity values in order to recognize the optimum ratio of the ester blends.

Synthesis, structure, oxygen stoichiometry, and electrical properties of doped ruddlesden-popper strontium cobaltite Sr1·875Ce0·025CoO4-δ, Sr1·875Ce0·025Co0·75Ni0·25O4+δ novel compounds

We report the synthesis of Sr1·875Ce0·025CoO4-δ and Sr1·875Ce0·025Co0·75Ni0·25O4+δ for the first time, each compound was synthesised using Co-precipitation and Sol-Gel methods, at 1050 °C for 144 and 120 h respectively. Oxygen stoichiometry was determined using Iodometric titration, we have noticed oxygen hypostoichiometry for Ce-doped compound and hyperstoichiometry state after Ni-doping. Electrical properties were studied for sintered pellets, Electrical resistance was measured in the range (−0.5–+0.5 v). Specific electrical resistivity and electrical conductivity were calculated from resistance measurements. It was found that the Ce-doped compound has about three times higher conductivity (σC1 = 0.000000058423295 s cm−1) Compared with the Ni-doped one (σN2 = 0.000000022384787 s cm−1). Electrical Capacitance was measured at 1 kHz frequency, the relative dielectric constant εr, and the loss tangent tanδ were calculated accordingly. The results showed that the Ni-doped compound has higher capacitance but lower εr and dissipation factor values.

The effect of thermal aging on solid insulating materials: A case study for dielectric loss and dissipation factor based evaluations under different voltage levels and frequencies

Investigating the dielectric performance phenomenon in insulating materials is critical for condition monitoring and early failure diagnosis. In this study, the effect of thermal aging on dielectric losses and dissipation factors of four insulating materials are investigated: PET, SBR/NR, presspaper and HDPE. A series of measurements at 4 kV and 10 kV with eight different frequencies between 50 Hz and 400 Hz are used to determine the dielectric loss and dissipation factor values of the materials during aging process. Thus, the non-ideal structure of electrical networks and the presence of harmonics are considered. Referring to the results, it is found that the level and frequency of the applied voltage greatly affects the performance of the materials. Also, it is seen that thermal aging have a significant impact on the dielectric properties of the materials. Furthermore, thermal aging effect on the results of different frequencies differs according to the material type.

The influence of post-annealing temperatures on XPS, XZ height of nanoparticles, and optical properties of Cu–Al doped ZnO films

In this article, using a radio frequency magnetron sputtering system at room temperature, Cu–Al doped ZnO films were deposited on quartz substrates. XPS studies have shown that the broad bands at around 932.5, 943, and 952 eV correspond to the Cu 2 P3/2 peak of Cu+1, Cu 2p3/2 of Cu+2, and Cu 2p1/2, respectively. In the case of Al2p3/2, the peak with binding energy 74.2 eV may be attributed to the presence of Al3+ oxide. The optical density, D opt, of films annealed at 600 °C has a maximum value about of 0.25. Films annealed at 600 °C have a minimum value of the fractal dimensions, D f, about 2.65. It is observed that films annealed at 500 °C, have a maximum value of the single layer. The minimum value of dissipation factor occurred in films annealed at 500 °C. It can be seen that with doping Cu and Al atoms into ZnO films, the oxygen vacancies were nearly removed and the quality of films was increased; hence the porosity which is introduced in ZnO films can be removed by Cu–Al doping of ZnO films. Due to high evaporation in films annealed at 600 °C, they were rougher and they have a maximum value of RMS roughness at about 4.68 nm. Films annealed at 400 °C have a minimum value of dissipation factor.

An Experimental Study and Statistical Analysis on the Electrical Properties of Synthetic Ester-Based Nanofluids

The rise in power demand today necessitates its generation and transmission at high voltages. The efficient transmission of electric power requires transformers with an insulation system that exhibits excellent dielectric properties. In this paper ZnO and CuO nanomaterials are utilized to investigate the dielectric characteristics of pure synthetic ester oil and its related nanofluids (NFs) from room temperature up to 60 °C at increments of 20 °C, including AC breakdown voltage, Dielectric Dissipation factor, and DC resistivity. The breakdown testing is carried out in accordance with experimental IEC-60156 requirements. The DC resistivity and dissipation factor of oils are measured using the Dissipation Factor meter, resistivity meter, and a heating chamber with an oil cell that follows IEC 60247 standard. The statistical analysis is performed on the breakdown voltages test values using the Weibull probability distribution model for better accuracy. From the results, it has been found that ZnO nanofluid possesses a higher breakdown voltage among all the tested liquids. Furthermore CuO nanofluid gives a minimum value of dissipation factor even at higher temperatures.

Synthesis and characterization of ZnO based varistor ceramics: effect of sintering temperatures

PurposeThe purpose of this paper is to investigate the effects of the sintering temperature on the microstructural, morphological and electrical characteristics of Zinc oxide (ZnO)-based varistors.Design/methodology/approachThis study used a conventional method to design and produce ZnO varistors by sintering ZnO powder with small amounts of various metal oxides. Furthermore, the effect of sintering temperature on varistor properties of (Bi, Co, Cr, Sb, Mn)-doped ZnO ceramics was investigated in the range of 1280–1350 °C.FindingsThe obtained results showed an EB value of 2109.79 V/cm, a Vgb value of 0.831 V and a nonlinear coefficient (α) value of 19.91 for sample sintered at temperature of 1300 °C. In addition, the low value of tan δ at low frequency range confirmed that the grain boundaries created in 1300 °C sintering temperature were obviously good.Originality/valueBased on the previous research on the ZnO-based varistors, a thorough study was carried out on these components to improve their electrical characteristics. Thus, it is necessary that those varistors have low leakage current and low value of dissipation factor to ensure their good quality. High breakdown fields and nonlinearity coefficients are also required in such kind of components. The effect of sintering temperature on the varistor properties of the new compositions (zinc, bismuth, manganese, chrome, cobalt, antimony and silicon oxides)-doped ZnO ceramics was studied in the range of 1280–1350 °C. Also, the microstructure and the phase evolution of the samples sintered at various temperatures (1280 °C, 1300 °C, 1320 °C and 1350 °C) were investigated according to X-ray diffraction and scanning electron microscope measurements.

Temperature Segment Compensation Method of Dissipation Factor for Insulation Diagnosis in Converter Transformer Bushing

Temperature compensation occupies a significant function in the insulation condition evaluation of converter transformer bushings based on the Frequency Domain Spectroscopy (FDS), which could influence the accuracy of its insulation diagnosis. In order to accurately obtain the variation law of FDS at different temperature, a Resin Impregnated Paper (RIP) insulation bushing for converter transformer was designed by the equivalence of maximum electric field, coaxial cylinder structure and RIP materials. The increment law of dielectric parameters both dissipation factor and capacitance at wideband frequency (1mHz ~ 10kHz) was measured for a quality RIP insulation samples at the temperature from 30°C to 100°C. 1) Under the uniform temperature, it was found that the value of dissipation factor was rising with the frequency from 10 Hz to 0.001Hz, while the tendency was reversed at the frequency from 100Hz to10kHz. 2) The minimum value of tan <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\delta $ </tex-math></inline-formula> from 0.001Hz to 10kHz could be driven to higher frequency moving (10Hz to 10kHz) by the action of temperature rising 30°C to 100°C.3) The effect of temperature on the lower frequency 0.001Hz ~ 1Hz tan <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\delta $ </tex-math></inline-formula> of RIP insulation closely conformed to the index law of Arrhenius equation, while it was in accordance with the linear decrease at higher frequency 1kHz ~ 10kHz. The effect of temperature on dissipation factor could be eliminated by curve segment shifting based the experiment equation, which it at 0.001Hz dissipation factor could be eliminated by curve shifting based the index equation originated Arrhenius equation. The method is beneficial to eliminate the influence of temperature on the dielectric spectroscopy test results, and then to eliminate the influence of temperature on the dielectric spectroscopy diagnosis of RIP bushings.

Spectroscopic, Mechanical and Electrical Studies on Surfactant Modified HTV-SiR/Nano Alumina Composites

Using an experimental approach, the effectiveness of nonionic surfactant, Triton™-X-100 in dispersing nano Alumina in high temperature vulcanized silicone rubber are studied in detail. Nanocomposites are prepared in varying concentrations of 0, 0.01, 0.05, 0.2, 1, and 5 phr levels by weight of the surfactant. Evidence to moderate dispersion of nano Alumina for composites at 0.01 phr and 0.05 phr weight loadings is gained from SEM pictures. Structural changes observed for the composites in FTIR spectra are examined and peaks identified. Thermogravimetric analysis shows some improvement in thermal resistance. However, an adverse effect on properties, such as volume resistivity, surface resistivity and dissipation factor are observed even at low surfactant loadings. A plausible role of surfactant as a plasticizer is explained with respect to the results of tensile strength. From this work, it can be inferred that surfactant at 0.01 phr may be taken as an optimum loading concentration for a desirable level of electrical properties, without compromising on insulation characteristics of volume resistivity and dissipation factor. Nonetheless, utmost caution needs to be exercised while employing Triton™-X-100 in compositions prepared for insulation applications because of inadequacies in values of volume resistivity, surface resistivity, dissipation factor and dry arc resistance even at low loadings.

Measurement of Dissipation Factor of Inner Layers of Insulation in Three-Core Belted Cables

This paper presents a substantiation of an approach for direct measurements of dielectric dissipation factor of layers of insulation between the conductors of three-core power cables. Proposed approach is based on grounding of the inspecteddielectric layer through the sufficiently low electrical resistance. The results of carried out analysis, which was carried out taking into consideration the presence of numerous parasitic parameters of tested layer of insulation due to the capacitive coupling between the electrically conductive elements of three-core power cable, have shown that for the case of sufficiently low value of used resistor the value of phase shift between the waveforms of voltage drop on inspected layer of insulation and resistor, through which this layer of insulation is grounded, coincides with the value of phase shift between the sine waveforms of current and voltage for parallel equivalent scheme of tested layer of insulation with power losses. Because of the dependence of dielectric power loss angle on the value of phase shift between sine curves of current and voltage, the presented approach for the measurement of dielectric dissipation factor is based on such coincidence of values of phase shift. Depending on the value of applied resistor, the value of dissipation factor is calculated on the basis of measured value of phase shift between the voltage drop on the electrical resistor, through which tested layer of insulation is grounded, and either the waveform of voltage dropon the inspected layer of insulation, or the waveform of applied voltage. Factors that affect the accuracy of measurement are discussed, equivalent schemes of tested three core power cable for various ways of applying testing voltage are presented and theexample of practical implementation of presented approach for dissipation factor measurement is also given. Further development of presented approach for dissipation factor measurement is supposed to include the comparative analysis of the results of its practical implementation with the results obtained by applying previously developed techniques based on aggregate measurements.

DIELECTRIC DISSIPATION FACTOR IN THREE-CORE POWER CABLES

This article is devoted to the analysis of components of variance of the results of measurements of dielectric dissipation factor of insulation layers between the conductive elements of the construction of three core power cables with paper impregnated insulation in a common sheath. The analysis of components of variance was carried out by applying presented relations for the direct calculation of the dielectric dissipation factor. The accuracy of presented relations for the calculation of variance components was verified. The results of carried out analysis have shown that the variance of the dielectric dissipation factor measurements is mostly determined by the variances of multiplication of measurements of aggregate values of dielectric dissipation factor and coefficients depending on the partial capacitances of tested three core cable.

Low temperature sintering of (1-x-y) BaTiO3-xBiFeO3-yKVO3 composition

Abstract In this study, the composition of (1-x-y) BaTiO3-xBiFeO3-yKVO3 (x = 0.15; y = 0.01, 0.025) were successfully synthesized using a calcination at 700 °C for 2 h of mixed BaTiO3, BiFeO3, and KVO3. Previously, BaTiO3, BiFeO3, and KVO3 powders were respectively synthesized through oxalate co-precipitation, solid state reaction, and sol–gel self-combustion method. The substitution of 1 mol% and 2.5 mol% doped KVO3 successfully reduce the sintering temperature become ≈1050 °C from generally reported 1400⁰C-1500⁰C. The XRD pattern reveals the presence of a secondary phase which is also indicated by SEM images. Furthermore, the increase of KVO3 causes an increase of secondary phase then decrease the value of relative permittivity (er) and dissipation factor (tan δ).

Chemical Gardens as Electrochemical Systems: In Situ Characterization of Simulated Prebiotic Hydrothermal Vents by Impedance Spectroscopy.

In an early earth or planetary chimney systems, hydrothermal fluid chemistry and flow durations play a large role in the chimney's ability to drive electrochemical reactions for the origin of life. We performed continuous electrochemical impedance spectroscopy (EIS) characterization on inorganic membranes representing prebiotic hydrothermal chimney vents in natural seafloor systems, by incorporating an electrode array into a chimney growth experiment. Localized potential and capacitances profiles in the chimney reveal a dynamic system where redox processes are driven by transport phenomena, increasing rapidly due to disequilibrium until achieving equilibrium at about 100 mV and 1000 μF/cm2 . The impedance in the chimney interior is three orders of magnitude lower (100 Ohms/cm2 vs 100 KOhms/cm2 ) than at the ocean or the ocean/chimney interface. The calculated peak dissipation factor (DF) values are more than ten times higher (40.0 vs 3.0) and also confirm the elevated chemical reactivity in the chimney interior.

Fabrication and characterization of composites of a perovskite and polymers with high dielectric permittivity

Composites of strontium titanate (SrTiO3) at loadings up to 50 vol.% with polar poly(butylene terephthalate) (PBT) and non-polar linear low density polyethylene (LLDPE) were prepared to investigate their dielectric responses in the wireless frequency range. The SrTiO3 particles were uniformly dispersed in the polymers at low loadings, but were more bead-like and agglomerated at higher SrTiO3 loadings. The SrTiO3 has a strong nucleating effect on both polymers, increasing the crystallization temperature and reducing the crystallinity of both polymers. Dielectric properties of composites were measured between 2.45−5 GHz. Dielectric permittivity (ε') of composites at 2.45 GHz increased with increasing SrTiO3 content. ε' increased by a factor of 5 for PBT, from 3.7 for unfilled PBT to 16.5 and by a factor of ∼8.5 for unfilled LLDPE, from 2.3 to 19.7 for maximum SrTiO3 loading. The composites had similar dissipation factor values as the unfilled polymers. The Lichtenecker model was in good agreement with the experimental data.