DC Supply Voltage Research Articles

Low‐Voltage Low Noise Figure Down‐Conversion Mixer for Band #1 of MB‐OFDM System in 180 nm Complementary Metal Oxide Semiconductor Technology

Low‐voltage design is a challenge for Gilbert cell‐based mixers due to stacking transconductance and switching stage. This work addresses this issue by proposing a design of a low‐voltage down‐conversion mixer for band #1 of multiband orthogonal frequency division multiplexing (MB‐OFDM) system in 180 nm complementary metal oxide semiconductor (CMOS) technology. The mixer is tuned at band #1 at RF frequency of 3.432 GHz and IF frequency of 264 MHz. The proposed mixer uses folded cascode connection of LO and RF in order to increase headroom and to reduce the DC supply voltage for low‐voltage operation. Common gate configuration is used at RF transconductance stage to enhance the input bandwidth of the mixer. RF and LO ports are matched to 50 Ω using differential T and LC matching, respectively. The resistive source denegation technique is used to linearize transconductance with respect to the bias point. The common source stage is used at the IF port as a buffer cum matching circuit it. The simulation results of the mixer show the maximum conversion gain of 9.76 dB, 1 dB compression point (P1dB) of ‐16.25 dBm, the third‐order input intercept point (IIP3) of ‐4.70 dBm, an SSB noise figure of 9.036 dB, and S11of ‐19.490 dB at the supply voltage of 1.2 V. Excluding off chip components, proposed mixer records an active area of 926.35 μm2.

Flying capacitors multilevel inverter: architecture, control and active balancing

To improve efficiency and productivity of electric energy generators based on photovoltaic, wind or hybrid systems; several DC/AC conversion techniques have been developed and tested like multilevel inverters. Multilevel inverters are a performant solution for the ramp-up of converters. As soon as the DC supply voltage exceeds a few kV, it is necessary to combine switches, switching cells or converters. This paper presents a progressive study of an interesting type of these inverters namely flying capacitor multilevel inverters (FCMLI): architecture, evolutions, benefits and inconvenient. In fact, we processed 3-and 5-level FCMLI while presenting possible circuit schemes and simulation results on Matlab Simulink. Finally, a general formulation has been adopted and applied to a 17 level FCMLI.

Wireless Power Transfer and Management for Medical Applications: Wireless power

Wireless power transfer (WPT) plays an important role in medical devices that require contactless energy transfer for either direct powering or recharging their small batteries. Miniaturizing medical devices and improving their WPT link robustness against different variations (e.g., distance, alignment, and load changes) also demands an efficient and adaptive power-management IC (PMIC) to convert the incoming ac power carrier into one or multiple usable dc voltage supplies. This article summarizes the key techniques for WPT and PMIC design. It discusses different modalities for WPT, including inductive, ultrasonic, capacitive, and magnetoelectric (ME) methods, with a focus on their applicability in different types of medical devices with different dimensions, implantation depths, and power requirements. It is concluded that ultrasonic and ME modalities are suitable for WPT to deeply implanted small devices with low power consumption, while inductive and capacitive methods are more suitable for WPT to large implants with shorter depth and higher power consumption. This article also summarizes different PMIC techniques for inductive WPT, particularly conventional voltage mode and more recent current-mode (and reconfigurable) techniques, with an emphasis on their suitability for different input voltage and loading conditions.

A Control Method for SMA Robotic Actuators

Soft robots show remarkable benefits over conventional rigid robots due to their high energy density and other factors. We propose a circular soft robot integrating the control system, actuating it with several shape memory alloy (SMA) actuators. Our research methodology involved connecting the DC voltage supply and L298N module to provide uninterrupted power to the actuator and thence control the actuator via Arduino Uno MCU and TOF camera. We designed the controller to simultaneously complete the positioning and manipulation tasks. A novel method utilizing visual servo and closed-loop control algorithm was proposed and integrated into the controller. This method involves the implementation of multi-gait locomotion using SMA actuators. Additionally, the development of closed-loop dynamic controllers for a continuous soft robot is also evaluated. The proposed control model is designed and simulated on the MATLAB tool. To verify the efficiency of the proposed forward-feedback controller, simulations and experiments were conducted in the current study. A new control method using PID control based on the Kalman filtering algorithm and visual servo for the SMA actuator designed in this research is introduced. We conclude that applying spike excitation voltage would benefit the actuating performance. Overall, the experimental results demonstrated a promising future for the purposed control method.

Design An Infant Warmer With Android-Based Temperature Monitoring

Infant Warmer design testing or calibration with Android-based Temperature Monitoring is highly dependent on infant warmer modeling equipped with a microcontroller-based APGAR timer using 2 modes (water mode and skin mode) the timer can be activated by sound. The purpose of this research is to design an infant warmer tool with an Android-based temperature monitoring system using a research method consisting of several stages including the required voltage supply of AC 220V and dc voltage supply required by 5V, temperature setting in this Infant Warmer Design tool using temperature settings 36 - 37 °C , an effective distance of 8 meters of temperature monitoring, and a display on LCD devices and android apps. The result of this research is an infant warmer design module with Android-based monitoring and temperature monitoring with the application can work according to its function. The correction value measured in the temperature test was 33 °C at 0.16 °C, the temperature was 35 °C at 0.085 °C, the temperature was 37 °C at 0.1 °C, so the prototype could still be used. The relative percentage of errors is 0.2 % - 0.4% .from the comparison between kalibtor incu analyzer tools.

Vacuum Arc Evolution Characteristics in Low-Voltage DC Current Interruption Under Composite Transverse Magnetic Fields

Based on our novel dc vacuum interruption technology under composite transverse magnetic fields (TMFs), the arc voltage of dc vacuum arc can be effectively improved to interrupt the dc current. The objective of this work is to experimentally investigate the vacuum arc characteristics and their evolution in dc current interruption under composite TMFs. The composite TMFs were generated by both multipole permanent magnets and cup-type TMF contacts. The vacuum arc photos were recorded by a high-speed camera. The experimental results indicate that under these composite TMFs, the dc current could be successfully interrupted, which was closely related to the dc vacuum arc characteristics and their evolution. The experimental dc current and voltage were less than 500 A and 500 V. First, the evolution of the dc vacuum arc could be divided into Stable and Unstable stages, according to the characteristics of the arc voltage waveform. In the Stable stage, the dc vacuum arc might be stagnated, constricted, and rotated with a stable arc voltage of 20 V. In the Unstable stage, the dc vacuum arc was transferred to the outer periphery of the contact in the form of a ``C''-shape, and the arc voltage significantly increased higher than the supply dc voltage. Second, there was an Extinction Area in the middle of Area 4 under the composite TMFs, which made the dc vacuum arc always extinguish at this position. Third, repeated fluctuations of the arc voltage are caused by the formation and extinction of the ``C''-shaped arc. Finally, when the distance between the igniting area and Extinction Area increased, the duration of the Stable stage increased, while the duration of the Unstable stage decreased.

Three-Phase Six-Level Multilevel Voltage Source Inverter: Modeling and Experimental Validation.

This research proposes a three-phase six-level multilevel inverter depending on twelve-switch three-phase Bridge and multilevel DC-link. The proposed architecture increases the number of voltage levels with less power components than conventional inverters such as the flying capacitor, cascaded H-bridge, diode-clamped and other recently established multilevel inverter topologies. The multilevel DC-link circuit is constructed by connecting three distinct DC voltage supplies, such as single DC supply, half-bridge and full-bridge cells. The purpose of both full-bridge and half-bridge cells is to provide a variable DC voltage with a common voltage step to the three-phase bridge’s mid-point. A vector modulation technique is also employed to achieve the desired output voltage waveforms. The proposed inverter can operate as a six-level or two-level inverter, depending on the magnitude of the modulation indexes. To guarantee the feasibility of the proposed configuration, the proposed inverter’s prototype is developed, and the experimental results are provided. The proposed inverter showed good performance with high efficiency of 97.59% following the IEEE 1547 standard. The current harmonics of the proposed inverter was also minimized to only 5.8%.

Design and Implementation of High Performance PPSK demodulator in Biomedical Implant

Background/Objective: The important challenge for the realization of hearing aids is small size, low cost, low power consumption, and better performance, etc. Keeping these requirements in view this work concentrates on the VLSI (Very Large Scale Integrated) implementation of the analog circuit that mimics the PPSK (Passive Phase Shift Keying) demodulator with a low pass filter. Methodology: This research deals with RF Cochlear implant circuits and their data transmission. A PPSK modulator is used for uplink data transmission in biomedical implants with simultaneous power, data transmission. This study deals with the implementation of a PPSK demodulator with related circuits and a low pass filter which are used in cochlear implants consumes low power and operates at 14MHz frequency. These circuits are designed using FINFET 20nm technology with 0.4v DC supply voltage. Findings: The performance of the proposed design over the previous design is operating at low threshold voltage, reduces static leakage currents, and often observed greater than 30 times of improvement in speed performance Novelty: As the conventional design with the same supply voltage(0.4v) exhibit high power dissipation and delay and require more amount of time to demodulate the signal. Whereas the proposed FINFET based monostable circuit and PPSK demodulator with a low pass filter has proven better in terms of less delay and power dissipation and can transmit the data with less bit error rate in stipulated time. Keywords: Cochlear Implant (CI); Fin Field Effect Transistor (FINFET); Electrode Array; Back Telemetry; PPSK Demodulator

Electric and Magnetic Design of a Deployable WPT System for Industrial and Defense UAV Applications

The following paper presents a highly efficient wireless power transfer (WPT) system for unmanned aerial vehicle (UAV) applications. The proposed system is designed as a deployable landing pad, where UAVs can be efficiently charged at distances up to 20 cm, while the UAV is landing. The operation frequency is 50 kHz. The current work presents two major contributions that help improve this aspect: a novel RX charging pad geometry and an unconventional design of a low-voltage, high-power DC–AC inverter using discrete MOSFET transistors. Both the pad’s geometry and the inverter are designed specifically for UAV applications. The input DC to output AC system efficiency peaks at approximately 95%. The peak efficiency is obtained at power transfers of 625 W. A major difference between the present design and traditionally used state-of-the-art systems is the low DC supply voltage requirement of just 24 V, compared with typical values that range from 50 up to 300 V at similar output power.

Adaptive neuro‐fuzzy inference systems (ANFIS) controller design on single‐phase full‐bridge inverter with a cascade fractional‐order PID voltage controller

AbstractAdaptive neuro‐fuzzy inference system (ANFIS) technique is a significant alternative of research which is structured with a combination of two soft‐computing strategies of fuzzy logic and artificial neural network. The design of ANFIS controller for a single‐phase full‐bridge inverter with pulse width modulation is demonstrated here in the presence of different disturbances. Moreover, an LC filter is designed to decrease the disturbing harmonics which the stability of the filter can be noted as an important issue. Based on the fuzzy C‐mean clustering method used for decreasing fuzzy rules, the computational burden has been improved resulting in faster dynamic performance. This method considers the system as a black‐box structure which omits the need for an exact model of system and can be an appropriate technique for ill‐defined systems. Additionally, to deal with the variations of supply DC voltage, a fractional‐order proportional‐integral‐derivative controller is designed which is tuned by particle swarm optimiser algorithm and can generate a sinusoidal reference for the system input. This double‐loop control technique is known as cascade control strategy. It can be seen that ANFIS scheme provides appropriate results with less computational burden and simple structure with optimised responses in challenging conditions. The capability of the proposed method is validated for different operating conditions through simulation and experimental results.

Rancang Bangun dan Evaluasi Kinerja Kotak Pendingin Berbasis Termoelektrik

The cooler is one of the necessities for humans to store food, drinks, vegetables, fruit, meat and so on. Refrigeration systems that are commonly used today use refrigerants or freon/CFC (Chlor Fluoro Carbon) which are less environmentally friendly and expensive. To meet the need for cheap and environmentally friendly refrigerators, an alternative cooler is needed. One alternative refrigerant that has been widely used today is thermoelectric. The power source is from an adapter with an output voltage of 12V – 36V DC6A. Peltier Is a Thermo-Electric Module. This component is coated by a thin ceramic that contains Bismuth Telluride rods in it. When the DC supply voltage is 12volt-15volt and current is 2-5A. The cooling room material is Styrofoam, with a heat sink in the form of a heat sink fan. Variations are made on the amount of thermoelectric used. Data retrieval is done by installing a voltmeter, ammeter and thermocouple in a predetermined position then each measuring instrument will display the data. The data is then processed using the Microsoft Excel program which can produce graphs. With a graphic form, discussion and conclusion can be done easily.

Analysis and design of class E-LCCL compensation circuit topology circuit topology for capacitive power transfer system

<p class="Abstract">This research introduces the analysis and design of Class E-LCCL for capacitive power transfer (CPT) system. The CPT Class-E LCCL system is able to operate at high-frequency with decreased capacitance plate size and at reduced power losses by minimising switching losses. Additionally, the design of a CPT Class-E LCCL power amplifier is less complicated, since it is usually lighter and smaller with comparative intolerance to different circuit variants; hence, enabling the possibility of miniaturising the system. In this work, the capability of the CPT Class-E LCCL CPT system powered by 24 V DC supply voltage while operating at 1 MHz was analysed via experimental works and extensive simulation. Lastly, a CPT Class-E LCCL system prototype was built, generating 10 W output power via a 0.1 cm air gap at a near-perfect efficiency level of 96.68%. These findings could be beneficial for household apparatus, medical implants, and charging consumer electronics.</p>

Research Based on Modeling and Simulation of the Transient Regime in Controlled Switching with High Power Switches

This paper addresses one of the current areas of interest in electrical engineering, which is controlled switching of high voltage circuit breakers. During their operation, the problem of controlled switching of high voltage circuit breakers in commutation regimes was studied. Several types of switching were analyzed, considered representative of the transient regime, depending on the type of load, on the defect that may occur on the power supply lines, as well as depending on the position of this defect (near or far). The study carried out in the paper includes simulations of the controlled connection/disconnection operations in a transient regime, assuming the existence of different kinds of defects. To perform the study and simulations in the transient regime, a model, implemented in Matlab, was used for a time interval located around the origin of the time axis. The study included the dependence of the SF6 circuit breaker switching process on the following parameters: the DC voltage supply, ambient temperature and oil pressure in the circuit breaker actuator. The validity of the theory presented in this paper, in addition to being validated by simulations, is proven by the fact that the protection system currently in use at the power station of an 800 MW power plant, at the 400 kV power line, is based on the principles presented in this paper. The theory presented in the paper has been implemented in industry for nearly two years, and the results confirm that the theory presented in the paper is fully applicable in high voltage power stations.

A Scalable High-Power Microwave Source Based on Coherent Stimulated Emission

Future moderate-band (MB) high-power microwave sources will take advantage of having a small size and a low cost. However, the output power of existing designs is limited by the dc voltage supply. To tackle this issue, this article proposes a novel scalable high-power microwave source based on the concept of coherent stimulated emission. The proposed microwave source consists of an antenna array, in which the two arms of each dipole antenna are connected with a fast-rise time switch and charged by a dc voltage source. Each antenna unit is triggered by the incoming wave radiated from the previous unit and then oscillates and correspondingly produces a new electromagnetic wave to trigger the next one. Both simulations and experiments show that the output waves of multiple antenna units are in phase, and the output power is accordingly enhanced. Compared with the existing MB high-power microwave sources, the proposed microwave source is able to significantly boost the maximum output power by applying more automatically triggered antenna units, featuring strong scalability and less limitation by the dc voltage supply.

Investigation into Class E/F3 with Parallel Network

The system of equations for processes in the amplifier output network is analytically formulated. This system of equations considers parameters of resonant networks at higher harmonics. To calculate amplifier output network, the system of five equations was built for five unknowns, to which the condition of positive second voltage derivative at extremum of drain voltage was added. Two equations correspond to class E conditions, another two — quadrature waveforms at load and at additional resonant network. The last equation is the condition of extremum at the point near middle of drain voltage pulse. This system was solved using computer algebra program. The circuit elements and waveforms were calculated using the derived parameters. By choosing different parameters, it is possible to obtain various amplifier realizations, which will demonstrate features of different class F variants. The obtained amplifier parameters drain voltage and current waveforms were verified with calculated ones using the harmonic balance simulating software. The variant, which is closer to class E/F3 mode, was chosen to build an experimental amplifier prototype on frequency 2MHz using IRF530 MOSFET as a switch. The prototype was tested in the range of supply dc voltage up to 24V with the output power greater than 6W, while the amplifier efficiency was >80%. In the experiment, the ratio of peak drain voltage to dc supply voltage was measured to be 3.3 at the duty ratio 50%, unlike class E amplifier, where this value is around 3.65, and on practice, considering non-linear drain to source capacitance, it may achieve 4. The experimental second harmonic level amounted to be -20 dB relatively to fundamental, and the third one — 28.5 dB, which is due to an additional second harmonic filter. The paper results are useful for introduction of such circuits to practice.

The design of an efficient class E-LCCL capacitive power transfer system through frequency tuning method

In this work, the optimum zero voltage switching (ZVS) of Class E-LCCL capacitive power transfer (CPT) was determined via frequency tuning method. Through this an efficient system can be guanranteed although there is a change in the capacitive plates distance. This study used a Class-E LCCL inverter, as it can operate at a high alternate current frequency, besides producing low switching losses and minimal power losses. Specifically, this study conducted simulations and experiments to analyse the performance of an LCCL CPT System at 1 MHz operating frequency and 24 V DC supply voltage. Using an air gap distance of 0.1 cm, the designed CPT system prototype successfully achieved an output power of 10W and an efficiency of 95.45%. This study also found that by tuning the resonant frequency of the Class E-LCCL system, the optimum ZVS can be obtained although capacitive plate distance was varied from 1-3 cm via experimental. The results of this study could benefit medical implant and portable device development, consumer electronics, and environments that involve electrical hazards.

Modelling Home Appliances of DC House Based on Rooftop Photovoltaic Power Supply

The implementation of rooftop photovoltaic (PV) system in Indonesia mostly using inverter to convert the DC voltage supply into AC voltage supply to power the AC home appliances. This inverter is a complex and expensive electronics system. Many of the rooftop PVs are in fault condition due to the failure of their inverters. Therefore, the trends of applying everything’s DC source has been recently developed. This paper examines the modelling of several home appliances (i.e., refrigerator, television, washing machine, air conditioner, crockpot, laptop, mobile phone charger, and LED lightings) of a DC house, which is powered by the rooftop PV using the MATLAB/SIMULINK platform. This proposed model considers the PV (solar cell) module, chargecontroller, battery, and the home appliances as the end load of the system. As the results, this model then analyses and compares to the PV system that powered the AC home appliances to get better vision of DC home appliances that can be implemented in the community

A Common Drain Operational Amplifier Using Positive Feedback Integrated by Metal-Oxide TFTs

This paper presents a common-drain-based operational amplifier (OPAMP) fabricated by mono n-type indium-zinc-oxide (IZO) thin-film transistors (TFTs). Positive feedback technology is employed to the load TFTs by cross-coupled connection in order to boost the voltage gain of the common-drain differential pair. The OPAMP exhibits an open-loop voltage gain (Av) of 27 dB over a −3 dB bandwidth (BW) of 8.4 kHz at a DC supply voltage of 10 V. The measured unity-gain frequency (UGF), phase margin (PM) and DC power consumption are 119.4 kHz, 36° and 0.96 mW, respectively. Moreover, the chip area of the proposed OPAMP is as small as 0.37 mm $\times0.3$ mm since this concise topology needs only 10 TFTs.

Research for a three‐level T‐type grid‐connected converter based on the simplified three‐level SVPWM modulation scheme and neutral‐point potential balancing

ABSTRACTT‐type pulse width modulation controlled three‐level circuit is the mainstream topology in current medium power distributed PV inverters, charging station and active power filter system with the advantages of high equivalent switching frequency, high efficiency, small filter inductance and small grid current harmonic. Aiming at the inherent problems of midpoint voltage fluctuation and complex of the traditional three‐level space vector pulse width modulation (SVPWM) scheme of a three‐level T‐type rectifier, a new equivalent method of SVPWM strategy used in three‐level converter based on acting time equivalence was proposed, which needs no trigonometric function, irrational operation, and complex coordinate transformation. By the means of rotating the target vector in other sectors to the first sector, the dwell time of vectors can be calculated by the unified formula, and the formula for calculating the dwell time is deduced based on two levels SVM. Then, the control problems of the neutral‐point voltage balance in T‐type three‐level converter topology are analyzed and studied. Through the PI control of electric charge of one capacitor, the neutral‐point voltage can be kept to be half of the DC supply voltage stably. To verify the correctness and effectiveness of the proposed control strategy, a complete simulation model and experimental prototype platform under the digital control is established. The results show that the implementation of this method is very simple and it could decrease calculation error and keep the neutral point potential balance, which makes the results more accurate. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

Design of robust self‐tuning regulator adaptive controller on single‐phase full‐bridge inverter

This paper depicts a self-tuning adaptive control method along with a novel robust procedure to system identification which is applied to a single-phase full-bridge Inverter with LC filter by Pulse Width Modulation (PWM). Moreover, an LC filter is designed to decrease the disturbing harmonics produced by PWM which, the stability of the filter can be noted as an important issue. On the other hand, a dynamic change of the inverter can lead to instability issues in which the proposed approach can overcome this problem and perform with a great response. Due to the parametric uncertainty on a full-bridge inverter and other disturbing factors, a digital adaptive controller is proposed which is performed by minimum degree pole placement (MDPP) technique combined with Improved Exponential Regressive Least identification (IERLS) algorithm. To prevent the undesired influences of high variance noises and disturbance on the performance of the identification approach, a robust identification algorithm is introduced which is capable of keeping the parametric estimation process in a desired range. Additionally, to deal with the variations of supply DC voltage, a proportional-integral-derivative (PID) controller is designed. Finally, the experimental and simulation results are performed by Matlab-Simulink to show the validation of the work.