Medium voltage range energy harvester application using boost converter

Energy obtained from the surrounding is usually very low and scarce. Such energy can be found from the vibration, solar and heat to name few. Often this energy is less than 1.5 V. Based on this motivation, DC-DC boost converter circuit is choose and design to convert low energy to sufficient amount to be used in normal circuit device and system application. This paper introduces a medium range output voltage using conventional DC-DC boost converter for low input supply range. Simulation has been done and compared with the experiment results. The purpose of this paper is to show the possibility of conversion very low energy to up to 50 V and to discuss a brief operation involved. A linear 4 V to 49 V output voltage trend was obtained from the experiment, under low switching frequency, 2 kHz. The targeted input used in this paper is between 0.1 V to 1.5 V suitable for energy harvesting purpose

Parasitic consideration for differential capacitive sensor

Parasitic integration for a single supply differential capacitive sensing technique is presented in this paper. In real capacitive sensor measurement, parasitic impedance exists in its measurement. This paper objective is to study the effect of capacitive and resistive parasitic to the capacitive sensor circuit. The differential capacitive sensor circuit derivation theory is elaborated first. Then, comparison is made using simulation. Test was carried out using frequency from 40 kHz up to 400 kHz. Result is presented and have shown good linearity of 0.99984 at 300 kHz, R-squared value. This capacitive sensor is expected to be used for energy harvesting application

A DC-DC circuit using boost converter for low voltage energy harvesting application

A DC-DC step-up voltage converter is designed to convert a very lowvoltage supply, 35 mV such as fromthe thermal energy source from body heat. The converter can generate an outputvoltage up to 210 mV, approximately six imes its initial input voltage over afrequency of 36 GHz. The effect of switching transistors, inductor current,rise and fall time is also highlighted. The circuit operates using 2 µH inductor and 0.01 fF load capacitor, is simulated usingPSpice Simulation tool. This voltage converter is suitable for energyharvesting application in implanted electronic devices

Parametric sweep analysis of medium voltage range boost converter for energy harvester application

This paper presents a parametric sweep analysis discussion on proposed DC-DC boost converter circuit for low and wide voltage supply range. Analysis is initially done using computer simulation and then tested with experimental work. Results are combined and discussed in details. In this work, effect of parameter such as input voltage, switching frequency and inductance is presented in details. A linear conversion has been observed in this work. Low DC input voltage of 100 mV to 1.5 V is used and successfully converts to up to 50 V in linear inclination, considering CL = 10 µF, and RL = 10 kΩ. The circuit parameter for this voltage range are L = 100 µH, D = 50 %, and 2 kHz frequency operation. This circuit can be used for energy harvesting purpose and medium voltage application such as aircraft, wireless measurement system and automotive

Parametric analysis of single boost converter for energy harvester

This paper presents a conventional DC-DC boost converter for low and wide voltage supply range, suitable for energy harvesting purpose. The output voltage can be increased by controlling the transistor switching frequency, duty cycle,inductance, load capacitor, rise, and fall time. Both computer simulation and experiment results are performed in details. Experiment results have shown an error less than 6 % with the simulation. A linear trend of output voltage in the range of 4 V to 49 V is successfully converted from 100 mV to 1.5 V input voltage using low switching frequency of 2 kHz. The circuit parameter for this voltage range are L = 100 μH, D = 50 %, tr = tf = 2.9 μs considering CL = 10 μF, and RL = 10

ISOLATION AND CHARACTERIZATION OF MICROCRYSTALLINE CELLULOSE FROM OIL PALM FRONDS USING CHEMO-MECHANICAL PROCESS

This study investigates the characteristic of the microcrystalline cellulose (MCC) isolated from oil palm (Elaies guineensis) fronds using acid hydrolysis method. The morphology and size of the MCC were characterized using both Sherrer equations for X-ray diffraction (XRD) result and transmission electron microscopy (TEM). The thermal stability of MCC was determined from thermogravimetry analysis (TGA) profiles whilst, Fourier transform infrared spectroscopy (FTIR) was used to analyse the chemical modifications that occurred under these conditions. The XRD results showed that the MCC isolated from oil palm fronds (OPF-MCC) fibres had an average diameter and crystallinity index of 12.15 nm and 60.1 % respectively. Both the FTIR and the XRD indicated that lignin and hemicellulose contents decreased while the cellulose-I polymorph remained constant. Thermogravimetric analysis (TGA) revealed that OPF-MCC had higher thermal stability compared to the OPF fibres. The study revealed the potential applications of the MCC isolated from the oil palm biomass as green reinforcement or/and fillers in the production of biodegradable biocomposite

Single supply differential capacitive sensor with energy harvester compatibility

This paper presents a single supply differential capacitive sensing technique suitable to be used with a hybrid energy harvester in providing power to the circuit. The proposed differential capacitive circuit is designed based on the available off-the-shelf components. Theoretical and experimental study has been carried out to observe the performance of the circuit for various excitation frequencies. Tests that were carried out include using excitation frequencies ranging with a 0.1 pF capacitance change. Results from 40 kHz up to 400 kHz show a high level of linearity up to a 0.999 R-squared value. Range of capacitance detection can be increased by controlling the feedback capacitor, Cf, and the filter components, Rd and Cd. The sensitivity range is from 0.004 to 0.122 mV per every fF change,with ± 5 % error. The circuit consumes 3.83 mW, with a 3.3 V supply voltage. This circuit is also suitable for a wireless sensing node application

Exploring the effect of cellulose nanowhiskers isolated from oil palm biomass on polylactic acid properties

In this work, polylactic acid (PLA) reinforced cellulose nanowhiskers (CNW) were prepared through solution casting technique. The CNW was first isolated from oil palm empty fruit bunch microcrystalline cellulose (OPEFB-MCC) by using 64% H2SO4 and was designated as CNW-S. The optical microscopy revealed that the large particle of OPEFB-MCC has been broken down by the hydrolysis treatment. The atomic force microscopy confirmed that the CNW-S obtained is in nanoscale dimension and appeared in individual rod-like character. The produced CNW-S was then incorporated with PLA at 1, 3, and 5 parts per hundred (phr) resins for the PLA-CNW-S nanocomposite production. The synthesized nanocomposites were then characterized by a mean of tensile properties and thermal stability. Interestingly to note that incorporating of 3 phr/CNW-S in PLA improved the tensile strength by 61%. Also, CNW-S loading showed a positive impact on the Young’s modulus of PLA. The elongation at break (Eb) of nanocomposites, however, decreased with the addition of CNW-S. Field emission scanning electron microscopy and transmission electron microscopy revealed that the CNW-S dispersed well in PLA at lower filler loading before it started to agglomerate at higher CNW-S loading (5 phr). The DSC analysis of the nanocomposites obtained showed that Tg,Tcc and Tm values of PLA were improved with CNW-S loading. The TGA analysis however, revealed that incopreated CNW-S in PLA effect the thermal stability (T10,T50 and Tmax) of nanocomposite, where it decrease linearly with CNW-S loading

Bionanocomposite based on cellulose nanowhisker from oil palm biomass-filled poly(lactic acid)

Cellulose nanowhiskers (CNW) extracted from plant fibers exhibit remarkable properties that make them suitable for use in the development of bionanocomposites. CNW have demonstrated the capability to enhance the properties of a polymer matrix at low filler loading. In this study, poly (lactic acid) (PLA) bionanocomposites were prepared using the solution casting technique, by incorporating the PLA with the CNW obtained from an oil palm empty fruit bunch (OPEFB). Fourier transform infrared spectroscopy showed no significant changes in the PLA peak positions, which indicates that incorporating the CNW into the PLA did not result in any significant changes in the chemical structure of the PLA. Thermogravimetric analysis, on the other hand, revealed that the bionanocomposites (PLA-CNW) had better thermal stability than the pure PLA. The tensile strength of PLA-CNW increased by 84% with the addition of 3 parts of CNW per hundred resins (phr), and decreased thereafter. Moreover, a linear relationship was observed between the Young's modulus and CNW loading. Elongation at break, however, decreased with the addition of 1-phr CNW, and remained constant with further addition. Transmission electron microscopy revealed that agglomeration of CNW occurred at 5-phr loading, consistent with the tensile strength results. Overall, the CNW obtained from OPEFB can enhance the tensile and the thermal properties of bionanocomposites

Current behavior analysis of the single supply differential capacitive sensing

Differential capacitive sensing technique has gained popularity in capacitance measuring system due to its high symmetrical implementation, easy to be implemented using discrete components and has a characteristic of high linearity in its system. However, very few work has reported on the differential CVC system that is able to operate at a high frequency operation especially when using discrete method. In this work, a differential CVC is proposed using discrete single supply, suitable for energy harvesting and WSN application. The method has emphasised on the rectifier current behavior analysis of the capacitive sensing circuit. Using this method, sensitivity of 0.04933 mV per 1 ƒF capacitance change is achievable with low power consumption of 3.83 mW. The proposed method has also shown high linearity of R-squared value 0.99788 between 5 and 9.5 pF capacitance change. Finally, the recorded DC output voltage is in the range of 1.6505 to 1.8725 V output with working frequency of 200 kHz operation