Low Power Absorption Research Articles

Dynamic Analysis of a Supercapacitor DC-Link in Photovoltaic Conversion Applications

In this work, a dynamic analysis describing the charge and discharge process of a supercapacitor for the DC-link between a photovoltaic source and a constant power load is presented. The analysis results in a complete nonlinear and dynamic model that can be used for simulation and control for DC–DC converters, achieving fast recharge times and accurate steady-state voltages in the DC link to avoid overcharging the supercapacitor during low power absorption scenarios. The proposed approach includes parasitic elements for the supercapacitor and efficiency effects on the conversion stage, proposing equations useful for design and control. Stability is also discussed for the charge process of the supercapacitor. Validation of the analytical model is performed by comparison with LTSpice simulation, confirming a good agreement between theory and simulation.

Karakteristik Lampu Hemat Energi Ditinjau dari Pengaruh Suplai Tegangan Listrik


 
 
 
 The circulation of Energy Saving Lamps or Self-Based Lamps in Indonesia, which promises the shape of lamps, variations in lamp power, lamp life, comparison of offered lamp brightness, low power absorption with brighter light, has caused many people to switch from using tube lamps and incandescent lamps to other types of lamps. this lamp. Indonesian Government regulation that requires LHE lamp manufacturers to include the Indonesian National Standard label as proof that the lamp is within the specified Efficacy limit. General Regulation of Electrical Installation and PT. PLN urges its consumers that electricity users can maintain the load power factor of not less than 0.8. This study aims to determine the amount of current consumption and electrical power required by LHE lamps labeled with SNI from the Panasonic, Shinyoku and ACR brands which were obtained randomly in the market. 10 lamps 18 watts, 220 volts as a sample, given a variation of the supply voltage between 110 volts to 240 volts with 10 volt steps. The results showed that the average real power at a voltage of 220 volts was in accordance with the labels on all brands. All three lamp brands have a power factor below 0.5. Characteristics of voltage to real power for Panasonic LHE obtained y = -0.0226x2 + 8.889x - 673.88, LHE Shinyoku y = -0.0002x2 + 0.3184x + 109.22, and LHE ACR y = -0.0003x2 + 0.2852x + 120.91
 
 
 

A Simple Strategy of Control DC-DC Converter as Power Supply on Household Lights

Light emitting diode (LED) lamps are lighting lamps that have high efficiency with very low power absorption. This lighting lamp is widely used in households, the working voltage is 110-230 volts AC. Under certain conditions, LED light with the driver can also be turned on using a DC voltage at a voltage of 120-125 volts DC. Storage of electrical energy from solar cells generally uses a 12 volt batteries with a large enough current capacity from 5Ah to 400Ah. If the driver LED light is turned on by a battery or battery with a voltage of 12 volts DC from the solar cell, the driver LED light will not light up. This is because the battery / battery voltage level is not high enough to turn on the drive LED light. An electronic device in the form of a DC-DC converter can be utilized to increase the voltage from 12 volts to a higher voltage. In this paper, a DC to DC converter with a voltage multiplier using the Cockcroft-Walton method is designed to be used to turn on LED light for household lighting. After testing, the output voltage from DC to DC is 125.2 volts and the output current is 0.0465 A with a lamp load of 5 watts, while the input voltage is 3.7 volts and the current is 1.49 A.

A Simple Strategy of Control DC-DC Converter as Power Supply on Household Lights

Light emitting diode (LED) lamps are lighting lamps that have high efficiency with very low power absorption. This lighting lamp is widely used in households, the working voltage is 110-230 volts AC. Under certain conditions, LED light with the driver can also be turned on using a DC voltage at a voltage of 120-125 volts DC. Storage of electrical energy from solar cells generally uses a 12 volt batteries with a large enough current capacity from 5Ah to 400Ah. If the driver LED light is turned on by a battery or battery with a voltage of 12 volts DC from the solar cell, the driver LED light will not light up. This is because the battery / battery voltage level is not high enough to turn on the drive LED light. An electronic device in the form of a DC-DC converter can be utilized to increase the voltage from 12 volts to a higher voltage. In this paper, a DC to DC converter with a voltage multiplier using the Cockcroft-Walton method is designed to be used to turn on LED light for household lighting. After testing, the output voltage from DC to DC is 125.2 volts and the output current is 0.0465 A with a lamp load of 5 watts, while the input voltage is 3.7 volts and the current is 1.49 A.

Multi-tone Switching Shunt Control by a PZT Network Embedded into a Fiberglass Panel: Design, Manufacture, and Test

Research in noise and vibration control has partially focused on semi-active attenuation techniques such as switching shunt control (SSC) systems. Among the various methods, SSC architectures exhibit several interesting advantages such as low power absorption and intrinsic adaptive capabilities. This approach may represent an acceptable compromise between passive and active solutions. In previous work the authors implemented and validated 1D and 2D numerical models, addressed to describe continuous simple isotropic structures under tonal excitations controlled by single-element SSC system. Further efforts were then directed to extend the applicability of those models to non-isotropic structures and to multi-tone control devices. In this article, a 6-PZT network multi-tone SSC system is presented, and embedded into a balanced fiberglass laminate. The network geometry is defined according to an optimization process following modal information. The former 1-channel control circuit was extended to drive up to four independent channels. The complete system dynamics was simulated by assembling the structural matrices into a Matlab code, where both the electromechanical coupling and the control circuit behavior were taken into account. The structure was excited by broadband sweep signals in a selected range. Numerical and experimental results were compared and discussed.

Role of metallic and composite (ceramic–metallic) supports on microwave heating of porous dielectrics

The heating of porous dielectrics, beef–air (b/a) and beef–oil (b/o), attached with ceramic, metallic or ceramic–metallic composite supports, has been studied analytically using microwaves. Three test porosities were considered, 0.3, 0.45 and 0.6. A preliminary understanding of enhanced heating and power absorption within the material was obtained from the average power vs slab depth plots. The maxima in power, also termed as ‘resonances’, are observed for specific sample thicknesses and the two consecutive resonances are termed as R 1 and R 2 modes. It is observed that, for both b/a and b/o samples, higher intensity of resonances for power absorption occur in the presence of metallic and alumina–metallic composite supports. The detailed spatial distribution of power illustrates that the sample attached with the metallic support attains lower power distribution for both b/a and b/o samples. The low power absorption near the unexposed face has been enhanced by ceramic–metallic composite support. The overall heating efficiency is also enhanced with ceramic–metallic composite supports. The optimal heating strategy has been derived based on large heating rate with small thermal runaway. Metallic support may be recommended as optimal heating strategy for higher porosities ( ϕ ⩾ 0.45 ) whereas alumina–metallic composite support may be suitable for smaller porosities ( ϕ ⩽ 0.45 ) for b/a samples. Metallic or alumina–metallic composite supports give optimal heating effects for b/o samples. For both b/a and b/o samples, the thermal runaway is larger at higher porosities.

Material Requirements For All-Optical Devices:Nonlinear Properties of Poly-4BCMU

The non-resonant third order nonlinearity of conjugated polymers appears to be potentially useful for all-optical devices in waveguide formats.[l,2] This nonlinearity manifests itself as an intensity-dependent refractive index which leads to a nonlinear phase shift over some propagation distance. Device research over the last few years has shown that there are certain minimum requirements for the nonlinear phase shift that need to be achieved over one absorption length of the material.[l,3] There are two principal sources of absorption, the usual linear absorption which is independent of fluence, and two photon absorption for which the absorption scales linearly with intensity. Thus the usefulness of a nonlinear material for all-optical switching devices can be evaluated from a limited number of material parameters, namely n2(in n = n0+ n2I where I is the local intensity), α0which is the low power absorption coefficient andβwhich is the two photon coefficient (in α = α0+βI). The problem for a given material is to identify spectral regions over which the minimum required phase shift can be achieved.

A bent laue crystal monochromator for angiography at the NSLS

A focusing Laue-geometry dual energy monochromator has been designed for the human coronary angiography project at the National Synchrotron Light Source. The monochromatic photon beams from (111) reflections from the cylindrically bent [110] waters of silicon focus and cross at the patient. The energy of one of the beam is just above the K edge of iodine, used as a contrast agent for the coronary imaging and the other beams's energy is just below the edge. The reflectivity of the crystals is enhanced due to bending by an order of magnitude over the dynamical value. This advantage is somewhat offset by limiting the vertical aperture in order to maintain a bandwidth of a few hundred eV in the beams. The major advantage of this device should be its low power absorption in the beam from the superconducting wiggler magnet.

Kinetic equation study of phonon-induced nonequilibrium states in superconducting films

The response of a superconductor to the injection of coherent longitudinal phonons is investigated using a Bardeen-Cooper-Schrieffer- (BCS-) type energy-gap equation and the coupled nonlinear quasiparticle and phonon kinetic equations of Chang and Scalapino. The superconductor is assumed to be a weak-coupling, isotropic film which is perturbed in a spatially uniform steady-state manner. The frequently used quasiparticle relaxation-time theory of Eliashberg is first used to study the effects associated with changing the temperature $T$ and with changing the frequency and strength of the phonon field. The effect of assuming that the quasiparticle relaxation time ${\ensuremath{\tau}}_{q}$ is independent of the energy for $T$ near the critical temperature ${T}_{c}$ is also examined. The solutions of the coupled kinetic equations for the quasiparticle and phonon distribution functions and the energy gap $\ensuremath{\Delta}(T)$ are then presented and compared to the results obtained from the relaxation-time model. It is seen that even for low-power absorption levels the relaxation-time model is valid only when the phonon escape time ${\ensuremath{\tau}}_{\mathrm{es}}$ is much shorter than the phonon pair-breaking time ${\ensuremath{\tau}}_{B}$. The experimental data of Tredwell and Jacobsen and their theoretical calculations using the relaxation-time model are briefly discussed in the light of these results.