Voltage Variations Research Articles

Performance parameters estimation of high speed Silicon/Germanium/InGaAsP avalanche photodiodes wide bandwidth capability in ultra high speed optical communication system

Abstract This paper has clarified the performance parameters estimation of high speed silicon/germanium/InGaAsP avalanche photodiodes wide bandwidth capability in ultrahigh speed optical communication system. The basic structure configuration of avalanche photodiode is clarified. The basic depletion region configuration schematic view is demonstrated. As well as the maximum electric field is indicated for impact ionization through avalanche photodiode in the presence of load. Various avalanche photo-detectors multiplication factor is clarified versus reverse bias voltage at room temperature. Different avalanche photo-detectors dark current is measured against avalanche photo-detectors volume at room temperature. Various avalanche photo-detectors effective doping concentration is demonstrated against ambient temperature variations. Si/Ge/InGaAsP avalanche photo-detectors excess noise factor is demonstrated versus the ionization ratio at room temperature (T = 300 K) and different ambient temperature (T = 350 K and T = 400 K). Various avalanche photo-detectors excess noise factor is measured clearly versus the multiplication factor at room temperature. Si/Ge/InGaAsP avalanche photo-detectors excess noise factor is demonstrated versus reverse bias voltage at room temperature. Si/Ge/InGaAsP avalanche photo-detectors noise equivalent power is clarified versus multiplication factor at room temperature. Various avalanche photo-detectors noise equivalent power is studied versus temperature variations. Si/Ge/InGaAsP avalanche photo-detectors sensitivity is measured in relation to the temperature variations. Different avalanche photo-detectors sensitivity is demonstrated in relation to reverse bias voltage variations at room temperature.

Enhanced Mileage and Efficiency in Lightweight EVs Through Innovative Regenerative Braking and Speed Control with Solar-PV Integration

This study introduces a novel way to regenerative braking based on a Brushless DC (BLDC) motor. The preferred way for braking is to use a variable Stator voltage from a multi-cell battery system DC-DC buck converter. The proposed brake system's performance was evaluated using a simulation. According to simulation results, the proposed regenerative braking system is both practical and effective. Furthermore, this study introduces the most essential technique for regenerative braking, which employs a BLDC motor to increase the mileage of lightweight electric vehicles

The effect of ohmic heating conditions and heating modes on gel properties of unwashed pre-rigor common carp (Cyprinus carpio) surimi.

Ohmic heating (OH) at different conditions (voltage: 15, 20, 25V; frequency: 1, 5, 10kHz) and one-step water bath (WB) were used to heat wash and unwash surimi prepared from fresh pre-rigor common carp. The optimal heating conditions were established through assessments of gel strength, Texture Profile Analysis (TPA), water-holding capacity (WHC), whiteness, and sensory evaluation. Then, the impact of heating modes on gelation properties of unwashed surimi based on the optimal heating conditions was investigated. The study findings indicated a significant enhancement in gel properties compared to WB. Unwashed surimi gel properties showed improvement when derived from freshly caught raw fish and subjected to OH treatment. Moreover, variations in frequencies and voltages were observed to influence the heating rate. Optimal gel quality was achieved at 10kHz 20V (10V/cm), facilitating swift progression through the gel deterioration stage, inhibition of protein hydrolyzing enzymes activity, and establishment of a stable gel network. Continuing to increase the heating rate would disrupt its network structure, resulting in diminished gel strength and WHC. The best quality of unwashed surimi gel was achieved by heating to 40°C for 30min, followed by heating to 90°C for another 30min (40°C 30min+90°C 30min) under 10kHz 20V. The gel strength increased when held for 1h at 40°C. For optimal heating efficiency, the heating mode of 40°C 30min+90°C 30min is recommended to prepare unwashed surimi gel. PRACTICAL APPLICATION: Ohmic heating, as a rapid food heat treatment method, can both increase the heating rate and improve the gelation properties of freshwater surimi. There is a wide range of potential applications for the heat treatment of the surimi.

Reliable Determination of Contact Angle from the Liquid Fence.

Traditional methods of measuring contact angles often face difficulties in precisely defining the three-phase contact points. A novel method for accurately defining three-phase contact points based on liquid fences is proposed in this article. The tested liquid is placed in a cubic liquid fence composed of a pair of narrow strips of the tested solid and a pair of transparent wide strips. The transparent wide strip serves as the measurement window, and the surface tension of the liquid on it can be almost ignored. In experimental measurements, the horizontal coordinates of the end points of the liquid profile are fixed by the liquid fence, thus determining the horizontal coordinates of the three-phase contact points, which helps to accurately survey the contact angle. Additionally, since the parameters of the liquid fence are known, the size of the contact angle can also be calculated by measuring the height of the liquid level dome inside the liquid fence. Using the electric wetting effect as an example, we experimentally extracted a series of liquid contour maps with circular tops and square columns under varying voltages. The relationship curve between contact angle and voltage variation was obtained using the above methods, and a contact angle variation tendency seemed to agree well with the theoretical value.

Performance Investigation of Boost Converter Based on Fuzzy Logic Using Mamdani Rules

Boost Converter is one type of DC converter that is often used for various purposes where the output voltage is equal to or higher than the input voltage. To get an output voltage higher than the input voltage commonly used by electrical and electronic equipment, a voltage increase is needed that can be varied as needed. One way to increase the voltage with a variable is to use the Boost Converter with Fuzzy Logic control. This research proposes a Boost Converter that can increase the variable direct voltage. Boost Converter proposed Fuzzy Logic using Mamdani's rules as a controller. Boost Converter is investigated on Open Jacks Boost Converter, Closed Loop Boost Converter and Boost Converter Fuzzy Logic Control Duty cycle on Boost converters using PID and Fuzzy Logic implemented using Simulink Matlab. The results of the investigation show that the Boost Converter designed in this study has worked well according to the purpose.

Period-1 Motions and Bifurcations of a 3D Brushless DC Motor System with Voltage Disturbance

Abstract: In this paper, the nonlinear dynamic system of a brushless DC motor with voltage disturbance is studied analytically via a generalized harmonic balance method. A truncated Fourier series with time-varying coefficients is utilized to represent the analytical variations of nonlinear currents and voltages within this dynamic system. Bifurcations of periodic currents and voltages are obtained, and their stability is discussed through eigenvalue analysis. The frequency–amplitude characteristics of periodic currents and voltages exhibit complexity in the frequency domain. Comparative illustrations are provided to contrast the analytical solutions with numerical outcomes for periodic currents and voltages. These analytical findings can be effectively employed for controlling the brushless DC motors experiencing voltage disturbances.

Development of RF plasma generator based on Class E Power Amplifier

Abstract The plasma produced at 2 MHz radio frequency has substantial energy release stability and can be used to modify a material’s surface. The objective of this research is to create a plasma generator operating at a radio frequency of 2 MHz and examine how voltage affects the plasma spectrum that is generated. An AD9833 frequency generator, a class E amplifier, and impedance matching are used in the design of a 2 MHz radio frequency plasma generator as power amplifiers to create plasma. Variations in voltage, gas, and gas flow have been used. The input voltage variations used were 10V and 15V from the power supply. Two different media, free air (atmospheric gas) and argon gas flow, are used for plasma generation. In free air, the plasma formed is Nitrogen plasma with a wavelength of 300 to 380 nm. Argon gas flow is given a variation of Argon gas rate of 2 LPM, and 3 LPM. The plasma formed is Argon plasma with a wavelength of 700 to 850 nm.

Analysis of the Impact of Unbalanced Connection of Consumers and Electric Vehicles on Voltage Variation and Voltage Unbalance

Analysis of the Impact of Unbalanced Connection of Consumers and Electric Vehicles on Voltage Variation and Voltage Unbalance

50‐3: Invited Paper: An Active‐Matrix High‐Channel‐Count Neurostimulation System Enabled by Flexible Thin‐Film Transistors

Advanced neurostimulation systems require intimate interface with brain or peripheral nervous system to provide a therapeutic modulation for patients experiencing neural function loss. To achieve these, it requires stimulators with high‐channel counts and mechanical flexibility. In this invited paper, we showed a 4T1C neurostimulation pixel circuit with an active‐matrix architecture, offering the opportunity for high‐channel counts. In addition, a 4‐mask photolithographic process for highly uniform organic thin‐film transistor (OTFT) integrated system was demonstrated for mechanical flexibility, which shows a high device yield of 100% (50/50) and small device variation in threshold voltage of 0.64 V and in mobility of 4.9%. By implementing OTFTs to this novel neurostimulation architecture, we fabricated an OTFT‐based high‐channel‐count neurostimulation system, showing a high stimulator yield of 71.0% and small variation of 15.6% for the output stimulation currents among pixels.

97‐2: Late‐News Paper: Development of High‐Mobility Indium‐rich IGZO TFT Device for IT OLED Display

High‐end MNT, NBPC OLED displays require high resolution and high‐speed driving characteristics. In addition, as an OLED backplane, a high mobility and excellent reliability characteristics of TFT are required. We have developed high mobility devices by using Indium (In‐) rich a‐IGZO. In the In‐rich a‐IGZO TFT process, a relatively large amount of oxygen is used compared to conventional a‐IGZO (In:Ga:Zn 1:1:1) in order to control the variation of the threshold voltage (VTH) caused by high carrier concentration. However, the increase in excess oxygen leads to a decrease in reliability, making it even more difficult to satisfy both VTH dispersion and reliability at the same time. We have developed a‐IGZO TFTs that have excellent reliability characteristics while satisfying VTH dispersion and mobility by controlling the vertical and lateral distribution of oxygen and hydrogen. Furthermore, it has been confirmed that the 27‐inch QHD OLED monitor, which incorporates high‐mobility a‐IGZO TFTs, satisfies the product reliability characteristics.

10‐4: Late‐News Paper: Precise Compensation of Device Variability in IGZO‐based Ferroelectric Thin‐Film Transistors for Enhanced Transparent Display Performance

We demonstrate the compensation of device‐to‐device variation in threshold voltage using programmable ferroelectric indium‐gallium‐zinc‐oxide thin‐film transistors. Furthermore, degradationinduced threshold voltage shift can be mitigated by programming, setting the characteristics back to their pristine state. This can be a promising alternative for the replacement of complex VT compensation circuits in display applications.

71‐3: High Resolution Pixel Circuit Using a Double‐Gate LTPS TFT for AMOLED Displays in AR and VR Applications

The new AMOLED pixel circuit for high‐resolution applications such as AR/VR has been proposed. The simultaneous emission is adopted to minimize pixel elements. The proposed circuit can compensate for variations of threshold voltage and sub‐threshold voltage even composed with 3 TFTs and 1 capacitor.

Time-of-flight technique for estimation of the energy of runaway electron bunches formed in magnetized gas diodes

Time-of-flight estimates of the kinetic energy of magnetically insulated bunches of moderately relativistic runaway electrons (RAEs) were obtained with the use of an air diode equipped with a drift section. The measurements have demonstrated that the bunch energy can be controlled by changing the conditions for RAE emission in an air diode with a sharply inhomogeneous electric field, which can be done by varying the cathode geometry and material and the length of the cathode-anode gap. It has been demonstrated that if the measured electron current peaks are resolved to within 10 ps, and the bunch duration and spread in RAE emission moments are close to this resolution, the characteristic energies of the bunches can be estimated with an accuracy of ≈10%. Examples of energy measurements are given for paraxial and tubular bunches accelerated at cathode potentials of up to −250 kV. The estimated characteristic energies of the bunches, even not corrected for drift losses in the fill gas, turned out to be greater than the energies that could be achieved for bunches accelerated in a vacuum diode with due account for the variations in diode voltage.

Adaptive Takagi–Sugeno (T–S) fuzzy observer based fault tolerant control for DC–DC converters with robustness against uncertainties

AbstractThis paper proposes a Takagi–Sugeno fuzzy system model based fault tolerant control scheme for DC–DC converters, which is robust against parameter uncertainties and achieves the output voltage of an ideal converter. The control involves estimating the duty cycle change in the form of a fault parameter required to track the output voltage, in the presence of several uncertain conditions including converter losses, variation in input voltage, and unknown and changing output load. An adaptive law is designed to estimate the fault parameter that guarantees state and parameter error convergence. The adaptive law is derived using the Lyapunov stability theorem and the required parameters are evaluated by solving a linear matrix inequalities optimization problem. The load resistance is estimated in parallel by using a Kalman filter and fed to the fault parameter estimation scheme. Furthermore, a fast and robust method to detect short and open circuit switch faults is also presented. The proposed technique offers a simple, yet effective method to regulate the output voltage under several faulty and uncertain conditions. The proposed technique is tested on a DC–DC boost converter simulation model and the demonstrated MATLAB/Simulink results show the effectiveness of the proposed algorithm.

Simulation and optimization of EMI filter of conducted emission for high voltage gain DC-DC converter

In the continuity of the work on design of high voltage gain DC-DC converter, used for feeding the CubeSat electrospray thrusters with a variable output voltage according to the maneuver size, this paper introduces a simulation of the converter model with MATLAB/Simulink to determine its conducted emission level. By referring to the MIL-STD-461 standard, a required passive electromagnetic interference (EMI) filter parameters are calculated to reduce, under thresholds, the converter noise. With consideration of the available volume and power constraints in this kind of satellite, the design of common-mode (CM) choke is optimized with proposed procedure optimization, so as to reduce its volume and electrical losses. Also, this optimization procedure can be generalized and applied for any passive EMI filter design.

Multifactorial evaluation of an ultra-fast process for electrospinning of recycled expanded polystyrene to manufacture high-efficiency membranes for nanoparticle air filtration

The increased production of polystyrene waste has led to the need to find efficient ways to dispose of it. One possibility is the use of solid waste to produce filter media by the electrospinning technique. The aim of this work was to develop an ultra-fast electrospinning process applied to recycled polystyrene, with statistical evaluation of the influence of polymeric solution parameters (polymer concentration and percentage of DL-limonene) and process variables (flow rate, voltage, and type of support) on nanoparticle collection efficiency, air permeability, and fiber diameter. An extensive characterization of the materials and evaluation of the morphology of the fibers was also carried out. It was found that recycled expanded polystyrene could be used in electrospinning to produce polymeric membranes. The optimized condition that resulted in the highest nanoparticle collection efficiency was a polymer concentration of 13.5%, percentage of DL-limonene of 50%, voltage of 25 kV, and flow rate of 1.2 mL/h, resulting in values of 99.97 ± 0.01%, 2.6 ± 0.5 × 10−13 m2, 0.19 Pa-1, and 708 ± 176 nm for the collection efficiency of nanoparticles in the range from 6.38 to 232.9 nm, permeability, quality factor, and mean fiber diameter, respectively. All the parameters were found to influence collection efficiency and fiber diameter. The use of DL-limonene, a natural solvent, provided benefits including increased collection efficiency and decreased fiber size. In addition, the electrostatic filtration mechanism was evaluated using the presence of a copper grid as a support for the nanofibers. The findings demonstrated that an electrospinning time of only 5 min was sufficient to obtain filters with high collection efficiencies and low pressure drops, opening perspectives for the application of polystyrene waste in the development of materials with excellent characteristics for application in the area of atmospheric pollution mitigation.

Robust optimal dispatching of power grid with the participation of virtual power plants

Abstract One of the key technologies for creating intelligent distribution networks is energy management systems, which allow virtual power plants (VPPs) to combine distributed flexible resources and accomplish unified scheduling and coordination. This paper presents a solid optimization model that compromises safety and economics for distribution networks involving virtual power plants. First, a power flow model for the distribution network is created to minimize voltage variation, operating cycle cost, and the safety operation of several AM (active management) methods as constraints. Second, a strong optimization model for the distribution network was built with the participation of virtual power plants, accounting for the unpredictability of the load and fresh energy. Finally, the problem was solved using the relaxation evolution technique, and the precision and potency of the suggested model were shown by doing a simulated comparison study on the upgraded IEEE33 node testing system.

P‐72: A Bidirectional Gate Driver Circuit with Scan Signal for Low‐Frame‐Rate LTPO AMOLED Displays

This paper presents a bidirectional gate driver circuit based on low‐temperature polycrystalline oxide thin‐film transistors for a low‐frame‐rate AMOLED display. Simulation results indicate the falling and rising times of the output waveform are all below 3.48 μs and 0.56 μs with the threshold voltage variations of TFTs, ensuring the stability of the proposed circuit. The output waveforms are also generated successfully for a frame rate of 1 Hz display panel and have no fluctuation in consecutive frames. Therefore, the proposed circuit is suitable for a low‐frame‐rate AMOLED display.

79‐3: Novel Mini‐LED Pixel Circuit with PWM Driving Method for Decreasing Power Consumption

This article proposes a mini‐LED pixel circuit that employs the PWM driving method to decrease power consumption. To achieve uniform current, the circuit compensates for threshold voltage variations of TFTs and VDD I‐R drops. Simulation results show that power consumption is ameliorated over 10.53% more than the 6T1C circuit.

P‐68: Oxide Semiconductor Thin‐Film Transistor‐Based Micro‐LED Pixel Circuit with External Current Setting System

We propose an oxide semiconductor thin‐film transistor‐based micro light‐emitting diode pixel circuit with external current setting system. The proposed circuit achieved stable operation using pulse width modulation with maximum error rates 1.2 % and 3.2 % under threshold voltage variations and mobility variations, respectively.