Power Supply Range Research Articles

Ultra-low-power CMOS ring oscillator with minimum power consumption of 2.9 pW using low-voltage biasing technique

Abstract The need for low-power low-voltage circuit so lutions increases significantly with the rapid spread of wireless sensor network (WSN) and energy harvesting applications. The design of Complementary Metal-Oxide Semiconductor (CMOS) oscillators in sub-threshold region is challenged by the limits of the minimum start-up sup ply voltage, the power available from the harvester, die area, the demand of fully integrated CMOS circuits, and the additional auxiliary circuits that are needed to stabilize the frequency vs a supply voltage V DD. In this work, low-power CMOS oscillator with a simplified design is proposed in order to overcome the aforementioned obstacles. The circuit is designed using 2.5 µm 2-polySi 2-metal CMOS technology from IMB–CNM (CSIC) [1] with a threshold voltage of n-channel metal oxide semiconductor NMOS and p-channel metal oxide semiconductor PMOS transistors of 0.86 and −1.52 V, respectively. The suggested oscillator is capable to start up even in the deep sub-threshold region at V DD of 0.25 V. Accordingly, the minimum power consumption is 2.9 pW with an oscillation frequency of 2 Hz. The circuit can produce a P–P voltage of the oscillation signal equal to the supply voltage within a power supply range of 0.25–1.25 V.

A 0.4-to-0.8 V 0.1-to-5 MS/s 10 b two-step SAR ADC with TDC-based fine quantizer in 40-nm CMOS

This paper presents an energy efficient two-step hybrid-domain successive approximation register (SAR) analog-to-digital converter (ADC). Comparator offset calibration and kickback noise reduction techniques are proposed to maintain the high dynamic range and elevated residual signal quality of the coarse ADC. A feedback adjustment technology is proposed to reduce energy consumption of voltage-to-time converter (VTC). The VTC offset and LSB gain error between the coarse ADC and fine time-to-digital converter (TDC) are calibrated to ensure the gain accuracy. The proposed SAR ADC is designed in a 40-nm CMOS process and occupies 0.0363 mm2 silicon area. The post-simulation results show the proposed ADC achieved a spurious-free dynamic range (SFDR) of 74.8 dB and a signal-to-noise and distortion ratio (SNDR) of 56.42 dB at 0.4 V supply voltage and Nyquist input rate. The operating frequency scales from 100 kS/s to 5 MS/s. The converter has a power supply range of 0.4–0.8 V, and the figure of merit (FOM) is 4.85–10.6 fJ/conversion step.

Modulation, Shaping and Replicability of UWB Chaotic Radiopulses for Wireless Sensor Applications.

A modulation method is proposed for generating identical UWB chaotic radio pulses using an analog generator of chaotic oscillations. The problem is on the edge of two contradicting requirements: (1) theoretical ability to produce a huge number of various-shape signals, because of high sensitivity to the initial conditions of the generator; (2) the necessity to reproduce oscillations of the same shape both in the receiver and in the transmitter for the implementation of coherent methods of signal processing. The considered method allows us to resolve this contradiction. A single-transistor chaotic oscillator with single power supply and frequency range 100 to 500 MHz is proposed. A mathematical model of the generator (a system of ODEs) was derived. A method of generating chaotic radio pulses with a reproducible shape that could be varied in a manner that is controlled and natural for UWB radio by means of changing the supply voltage of the chaotic oscillator is shown. The mathematical model of the generator is simulated numerically and proves the proposed ideas. The shaping and the replicability of UWB pulses was experimentally proven in an analog domain on a testbed with four instances of the chaotic generator.

A New Single-Phase Flying Inductor-Based Common Grounded Converter for Dual-Purpose Application

This paper presents a new common grounded flying inductor-based converter as power electronics interface suitable for application in both dc or single-phase ac grids using the same terminals. This topology enables direct connection of the negative terminal of the input dc power supply to the negative polarity of the converter output. Therefore, the leakage current is eliminated completely. The voltage boosting feature in single-stage and operation in a wide range of input dc power supply is the other benefit of the proposed solution. Since electrolytic capacitors are not used in the structure, the life of the converter is increased. The operation modes of the converter are explained in detail. Also, the design considerations for passive elements are discussed. To verify the accuracy of the performance of the proposed topology, a laboratory prototype (3.6 kW/6 kW) was built. Related experimental results are presented.

A 13b 600-675MS/s Tri-State Pipelined-SAR ADC With Inverter-Based Open-Loop Residue Amplifier

This article presents a 13-b high-speed pipelined-successive-approximation-register (pipelined-SAR) analog-to-digital converter (ADC). By utilizing the comparator metastability, a tri-state SAR logic is introduced to achieve a fast approximation process. The tri-state SAR outputs three states by one comparator after each comparison cycle, and the effective-number-of-bits (ENOBs) can improve up to 1 b when the metastability boundary is set at ±1/4 LSB. In addition, an open-loop inverter-based residue amplifier (RA) is proposed with simple circuit implementation. The RA gain is well defined by <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$g_{m}$ </tex-math></inline-formula> ratio and is immune to process, voltage, and temperature (PVT) variations. Fabricated in 40-nm CMOS technology, the prototype ADC achieves a mean signal-to-noise plus distortion ratio (SNDR) of 59.8–62.8 dB, with 1- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sigma $ </tex-math></inline-formula> than 1.7 dB, at 600–625 MS/s over −40° to 125° temperature range and 1.1–1.2 V power supply range, a 67 dB dynamic range (DR), and a 62.4 dB SNDR for a Nyquist input while sampling at 625 MS/s. The overall power consumption is 7.05 mW.

Topology Optimization of Regional Power Grid Under Large-Scale Access of Distributed Photovoltaic Power Generation

In order to avoid the impact of large-scale access of distributed photovoltaic power generation on regional power grid and minimize power grid line loss, a regional power grid topology optimization method under large-scale access of distributed photovoltaic power generation is proposed. Obtain the factors related to the line loss consumption of regional power grid and the access location and capacity of large-scale distributed photovoltaic power generation, as well as the power grid network structure and load. Take the minimum bus loss after large-scale access to distributed photovoltaic power generation as the objective function, and take the continuity, network structure, line relationship, node voltage, etc. as constraints, build the topology model of low-voltage power grid, Using k-means clustering algorithm, the power supply range of regional power grid after large-scale access of distributed photovoltaic power generation is divided into several regions. In each divided small region, KPSO algorithm is used to optimize the network topology, so as to realize the topology optimization of the whole regional power grid. The experimental results show that when the number of clustering centers is 4, the clustering effect of this method is the best and can effectively reduce the power supply line loss.

Distribution Network Grid Planning and Automatic Routing Based on Cluster Analysis Algorithm

In order to improve the efficiency of power grid enterprises under the background of new power reform, the author proposes a set of planning ideas and methods for medium-voltage distribution networks based on the optimal division of power supply grids. First, the layout of the main channel in the planning area should be determined to ensure the reservation of land resources. Then, on the basis of clarifying the purpose and principle of grid division, based on the selection of the nearest load backup substation and the load clustering method, the optimal division of the power supply grid should be realized on a global scale. Finally, in each power supply grid, the wiring mode and the primary and secondary construction and renovation standards are selected based on the classification of the supply area, and the main line wiring planning is carried out. For the grid frame in the transition year, in order to avoid repeated reconstruction and facilitate construction, the principle of piece-by-piece construction and reconstruction is proposed. The results show that by the target year, each power supply grid in the planning area will use two substations as power points, the power supply range of the main lines of each grid is limited to this grid, the lines between grids will not be connected, and the line connection rate will reach 100% and all meet the N-1 check. The proposed method follows the basic planning concept of “technically feasible and economically optimal” on the basis of overall planning and transforms the complex global planning of distribution network into local planning within each optimized grid, and it enables different planners to obtain a basically consistent grid optimization scheme, strengthens the scientificity and certainty of planning, and provides a reference for the revision and refinement of relevant guidelines, which has been practically applied.

Flower Shaped Oscillating Heat Pipe at the thermosyphon condition: Performance at different rotational speeds, filling ratios, and heat supplies

The performance of a very effective and innovative thermal device based on Pulsating Heat Pipes (PHP) in a rotating system is studied and analysed in the paper. The appliance called a Flower Shaped Oscillating Heat Pipe (FSOHP) is developed for use in industrial sectors and is arranged in the specific shape of a flower so as to obtain homogeneous heat reception from technological processes. The capillaries, with an inner diameter of 2.7 mm, were filled and tested, with HFE−7000 as a working fluid. This fluid, according to a confinement criterion based on the Bond or Garimella numbers, places the device in the range of thermosyphon operation, the description and experimental verification of which is addressed in this paper. The influence of rotational speed (0–300 rpm), heat input (300–450 W), and filling ratio (40–90%) on the thermal performance has been studied as an experimental research. Current research shows that a low boiling point liquid such as HFE−7000 can be used as a working fluid in a rotating system, and the thermal resistance of the process is characterised by a value of almost 100% higher compared to water. The maximum value of the heat flux value achieved was equal to 22.1 kW/m2 for HFE−7000, while for water it was more than four times higher and equal to 98.4 kW/m2. It was also observed that by increasing the Filling Ratio (FR) by up to 80%, the thermal resistance decreases to the lowest value of 0.05 K/W in speed conditions such as above 200 rpm. Results have shown that with respect to dimensionless numbers, despite going beyond the scope of the confinement criterion, FSOHP achieves a low value of thermal resistance and temperature stabilisation with characteristics very similar to those that describe standard pulsating heat pipe solutions in a stationary system. Furthermore, in a rotating system, an increase in heating power improves the thermal efficiency of the device only for FR >70%, while in a stationary system, an increase in the power supply range studied is always associated with a decrease in thermal resistance, regardless of the FR.

Design of Low Power High Speed Hybrid Full Adder: A Review

In this research, I present a new hybrid FA design (a blend of CMOS and transistor logic types) that tries to achieve high speed while consuming minimal power, hence the low PDP designation. Our proposed FA and seven other current FA designs were modelled on the spice with a 45 nm low power model file, a standard test bed, and a standard test pattern (56 input switching), and the impersonation results for eight designs are equivalent. Power outages, distribution delays, and PDP are all issues that need to be addressed. The results of simulations show that our suggested FA design has the shortest broadcast delays and the lowest PDP across the whole power supply and frequency range.

Ground Fault Analysis and Grounding Method of Static Power Converters in Flexible AC Traction Power Supply Systems

Flexible traction power supply system (FTPSS) can eliminate neutral sections of all catenaries and improve the poor power quality of railway substations. The static power converter (SPC) is the key equipment of FTPSS and its internal faults must be quickly identified and cleared with minimal impact on catenaries to ensure the safety and reliability. This article investigates the two-stage fault characteristics in FTPSS. Before blocking, overcurrent and voltage distortion may result in a wide range of abnormal power supply. After blocking, capacitor overvoltage becomes the primary problem threatening the safety of faulty SPC because of the energy feeding from other SPCs. Equivalent circuits are established and applied to various fault conditions. The most serious fault case can be found through the comparison, so the complicated large-scale simulation scanning can be avoided. A T-shaped grounding method is proposed to solve the problem of fault current and capacitor overvoltage. Based on the calculation and simulation results of several typical fault cases, the dimensioning criterion of grounding circuit is provided for reference. Moreover, a comprehensive scheme of grounding protection is designed to detect and isolate serious faults. The theoretical fault analysis and the proposed grounding method are verified by simulations and experiments.

Research on Desktop Wide Range Wireless Power Transfer Based on High Frequency Electric Field

This paper proposes a desktop wireless power transfer system that can wirelessly supply power to electrical equipment in a certain space above the aluminum foil using only a high-frequency electric field. Compared with other wireless power supply systems, this system has a smaller power receiving device and a wider power supply range, which is convenient for wireless power supply of portable electrical equipment and low-power electric vehicles. The power receiving device of the system is only the size of a mobile phone, and the power supply range can reach 1.2 m2. This article introduces the system design, electromagnetic field simulation and experiment of the desktop wireless power transfer system. The experimental results show that by using a mobile phone-sized receiving device to connect a light bulb and a fan, multiple loads can simultaneously receive power in a specific space above the desktop power supply. In addition, people can hold the power receiving device for wireless charging.

Research on optimization of power grid range and pre-control strategy of power flow in key areas under ty-phoon weather

Typhoons Typhoons are extremely destructive and the route trajectory is ex-tremely uncertain. The power grids in coastal areas are frequently attacked by typhoons, resulting in large-scale power outages. When a typhoon strikes, it is difficult to determine the trajectory, which may cause simultaneous fail-ures of multiple contact lines at the same time and the location of the failure is difficult to predict in advance. Based on the above background, this paper proposes a strategy for optimizing the power supply range of the power grid in key areas and pre-controlling the power flow under typhoon weather. First of all, this article will optimize the scope of key areas. The minimum overhead cable ratio, the optimal generator load capacity ratio and the minimum connection sec-tion power flow between the key area power grid and the external power grid are used as the optimization objective function, and the cuckoo search algo-rithm is used to supply power. Scope is optimized. Based on the above opti-mization results of the power supply range, a power flow pre-control strategy is proposed to ensure that the power flow of the connection section between the power grid in key areas and external power grids is zero by optimizing the output of generators, energy storage equipment, and load shedding, and finally ensure that the key areas under typhoon mode the grid can transition and operate stably.

Power supply system for electrical installations with electrical converters, grid, generator and solar sources

Over the past decades, the range and functionality of power supplies has expanded and changed significantly. This is primarily due to the continuous desire to reduce the weight and size characteristics of the power supply, to increase their efficiency, to use modern economical pulse control methods, integrated microcircuits, etc.

A Digital Improvement-Trimming a Digital Temperature Sensor with EEPROM Reprogrammable Fuses.

An EEPROM (electrically erasable programmable read-only memory) reprogrammable fuse for trimming a digital temperature sensor is designed in a 0.18-µm CMOS EEPROM. The fuse uses EEPROM memory cells, which allow multiple programming cycles by modifying the stored data on the digital trim codes applied to the thermal sensor. By reprogramming the fuse, the temperature sensor can be adjusted with an increased trim variation in order to achieve higher accuracy. Experimental results for the trimmed digital sensor showed a +1.5/−1.0 ℃ inaccuracy in the temperature range of −20 to 125 ℃ for 25 trimmed DTS samples at 1.8 V by one-point calibration. Furthermore, an average mean of 0.40 ℃ and a standard deviation of 0.70 ℃ temperature error were obtained in the same temperature range for power supply voltages from 1.7 to 1.9 V. Thus, the digital sensor exhibits similar performances for the entire power supply range of 1.7 to 3.6 V.

R&D of a fast timing electronics board for testing SiPMs

A general-purpose SiPM electronics board has been developed in this work. Compared with commercial driver boards, this electronics board has a wider power supply range (20 V–90 V) to suit various types of SiPM. This new board enables cascading batch tests to meet the needs for high-volume SiPM testing procedures. More importantly, the new board can test SiPM timing performance down to a few tens of ps.

Improved Atomization via a Mechanical Atomizer with Optimal Geometric Parameters and an Air-Assisted Component.

Atomization of liquid media is a key aim in various technological disciplines, and solutions that improve spray performance, while decreasing energy consumption, are in great demand. That concept is very important in the development of liquid fuel spray atomizers in high-efficiency microturbines and other generator systems with low inlet pressure and a wide range of power supply. Here we present a study of the liquid atomization characteristics for a new mechanical atomizer that has optimal geometric parameters and a preliminary swirl stage. In our air-assisted atomizer, air is introduced through a swirl chamber positioned at the exit of the mechanical atomizer. The optimized mechanical atomizer alone can achieve D32 drop diameters in the range of 80 to 40 µm at water supply pressures of 2 to 5 bar, respectively. The addition of an air swirl chamber substantially decreases drop sizes. At an air–liquid ratio (ALR) equal to 1, water pressures of 2.5 to 3 bar and air supply pressures 0.35 to 1 bar, D32 drops with diameters of 20–30 µm were obtained. In an air-assisted atomizer the parameters of the mechanical atomizer have a much stronger influence on drop diameters than do characteristics of the air-swirl chamber. Using a mechanical atomizer with optimal geometrical dimensions allows limiting the liquid supply pressure to 5 bar; but when an air-assisted component is introduced we can recommend an ALR ≈ 1 and an air supply pressure of up to 1 bar.

Design of Portable Phototherapy using PL-S UVB Lamp for Psoriasis Therapy

This research aims to design portable phototherapy using PL-S UVB lamp. The transformer DC power supply range used is step down transformer with 220 Volt primary input and 12 volt secondary output. The series of Driver Relay serves to control the mechanical relay in the on-off position, which corresponds to the changes received by the counting circuit, the circuit uses a BC 547A transistor and a 12V/5 pole DC relay and the diode used IN 4002/ IN4004. Resistance in this relay of 400 Ω. From the measurement results using digital multimeter obtained the voltage value in the IC LM7812 of 12.11 Volt and on IC LM7805 of 5.02 Volt. Ultraviolet radiation spectrum can penetrate the base layer of the dermis. Ultraviolet rays B can penetrate the base layer of epidermis skin.

An integrated low-power Binary-PAM based wireless telemetry circuit for implantable cardiac pacemakers

A low-power wireless telemetry circuit integrated in an analog front-end (AFE) chip for implantable cardiac pacemakers is presented in this paper. With an on-chip telemetry circuit, the electrocardiogram (ECG) data can be transmitted directly from the AFE chip to a programmer outside the human body. Such a direct-memory-access (DMA) scheme improves data transmission efficiency and saves the overall power consumption. The proposed telemetry system employs a near-field inductive-coupling link with oscillating frequency of 128 ​kHz and a binary pulse-amplitude-modulation (PAM) strategy to achieve higher reliability. It consumes lower power and reach a longer communication distance when compared to conventional on-off-keying (OOK) modulation method. In order to further reduce the power consumption, pulse width adjustment technique is adopted in the transmitter. Also, edge detection and window detection techniques are employed in the receiver, making it more robust and immune to noise, disturbance and clock skew. The AFE chip is implemented using a 0.35-μm CMOS technology and the telemetry circuit occupies an active area of 1150umX350 ​μm. Measurement results show that the proposed wireless communication circuit can operate under a power supply range of 2.0–2.8 ​V, and achieves a maximum communication distance of 12 ​cm with current consumption lower than 26 ​μA and bit error rate less than 10−5.

Harmonic Control for Variable-Frequency Aviation Power System Based on Three-Level NPC Converter

At present, three-phase 115V/360-800Hz variable frequency AC power system is mostly used in the main power system of More-Electric Aircraft. With the increase of EMA (Electro-Mechanical Actuator), EHA (Electro-Hydrostatic Actuator), DC/DC power supply and power electronic devices in More-Electric Aircraft, harmonic and reactive power problems are brought, which seriously affect the power supply quality of variable frequency power supply for aircraft. According to the characteristics of high frequency and wide range of aviation variable frequency power supply, this paper studies a three-level active filter which can effectively improve the power quality of aviation variable frequency power supply system. This paper analyzes the working principle of the diode clamped three-level topology active filter, and deduces its mathematical model; proposes the frequency detection of the aviation variable frequency power supply based on the improved Rife method; the ip-iq method based on the instantaneous reactive power theory, accurately detects the harmonic current of the aviation variable frequency power supply system; uses the quasi PR controller to track the current, and improves the harmonic suppression effect. Finally, the experimental hardware platform is built to verify the feasibility of the proposed control strategy.

A Design of Wide-range Frequency-tracking Ultrasonic Power Supply

Aiming at the problem that the frequency tracking range of commercial ultrasonic power supply on the market is narrow, which makes the load of ultrasonic power supply, a structure of transducer-horn-tool, difficult to match. This paper presents a kind of ultrasonic power supply based on TMS320F28335, which can track the frequency in a wide range(15-21kHz). The advantages, theory, software and hardware structure of the power supply are introduced, which can realize the functions of wide range frequency tracking, power regulation, human-computer interaction and so on. Experiments show that the power supply can well match the ultrasonic vibration load with a wide range of resonant frequencies, and has good human-computer interaction function.