Design Of Supply Research Articles

Design of a Novel Underground Coal Mine 127V Power Supply

In view of the current disadvantages of the large size, high cost and low power factor of custom transformers in China’s coal mine 127V power supply system, a novel type of unit-power factor rectifier based on OCC (One-Cycle Control) is proposed to supply the underground coal mine lighting system. The power supply consists of three stages, including a Vienna rectifier, a high frequency isolated DC-DC converter and an inverter. However, the first two stages of the control circuit use a coordinated control. The circuit is simple to control, unit power factor operation can be realized without the multiplier and input voltage detection and half of the voltage stress of the switching device can be reduced as well. The paper analyses in detail the basic working principle and double closed-loop control strategy of the new rectifier circuit. The correctness is fully verified by simulations.

The Holy Grail of Crypto Currencies: Ready to Replace Fiat Money?

The rise of crypto currencies, notably bitcoin, has fueled new and old debates about money. We discuss attempts to complement or replace fiat money by ‘stablecoins’. In a first step, we review today‘s endogenous and debt-backed money. Second, we analyse attempts to use stablecoins in order to overcome the inherent speculative and deflationary design of fixed supply coins like bitcoin. Building on theories stating that economic and liquidity expansion go hand in hand we find that stablecoins have flexible supply designs. However, we also find that the algorithmically planned allocation of new coins, that is characteristic of stablecoins, is inferior to contemporary ways of money creation for two reasons: (i) it is not market-based and (ii) it is not backed by a ‘We Owe You’. Moreover, it builds on outdated monetarist theories in an attempt to control prices. We predict that crypto-monetarism in its present formulations will fail because quantity adjustments are not a sufficient condition for stable prices. Finally, regarding price stability, we suggest the importance of overcoming the illusionary dichotomy between the real and the financial circuit in (crypto) monetary policy. We show that, in the real world, firms set prices according to cost-based pricing rules, so that changes in unit labour costs correlate well with inflation. As a consequence, and in line with a path-dependent and institutional perspective on the labour market, coordinated wage bargaining appears vital to achieve price stability. Against this backdrop, we propose that wages have to grow in line with productivity plus the inflation target. Such an approach, if properly complemented with fiscal, interest rate and fx policies, would not only benefit price stability, but also financial resilience and economic development at large.

Design and implementation of smart uninterruptable power supply using battery storage and photovoltaic arrays

The objective of this paper is to provide an uninterruptable power supply to the customers by selecting the supply from various reliable power sources such as solar photovoltaic, AC mains and battery storage systems. Initially, the load gets power supply from the reliable source (such as solar photovoltaic), if in case it is unavailable, then the proposed modules automatically switch over to the next reliable source (such as AC mains), and so on. If in case all proposed renewable energy sources (RESs) are unavailable than the proposed mod-ule automatically switch over to the local grid supply, if suppose the local grid supply is also unavailable then the proposed module au-tomatically switch over to the power storage bank. Therefore, the proposed intelligent/smart power module can improve the system per-formance and efficiency. The programming instruction of controller, the relay driver switches appropriate relay of sources to maintain uninterruptable power supply to the proposed utility of capacity 0.1kW. The proposed back-up system gets charged from the available reliable RESs with no pollution and noise, and it can also reduce the electricity bill. The proposed intelligent power module functions are displayed on LCD, it has been designed and analyzed in real time environment.

Parking Pricing and Design in the Morning Commute Problem with Regular and Autonomous Vehicles

Autonomous vehicles can profoundly change parking behavior in the future. Instead of searching for parking, autonomous vehicle owners get dropped off at their final destination and send their occupant-free cars to a parking spot. In this paper, we study the impact of parking in a bi-class morning commute problem with autonomous and regular vehicles. We consider a spatial distribution of parking spaces, which allows us to capture the parking location of travelers. In the equilibrium condition, autonomous vehicles leave home later (than regular vehicles), and park farther away from their destination. The regular vehicle travelers, however, leave home sooner to park closer to the destination with a smaller walking distance. The reverse occurs if regular travelers abdicate walking and take a faster mode from their parking space to the city center. To optimize the system, we develop temporal and spatial parking pricing strategies and a new parking supply design scheme, as practical alternatives for the conventional dynamic congestion pricing. The proposed parking pricing strategies incentivize commuters to adjust their travel schedules by charging a parking price that increases with distance from the city center. Hence, those who park closer to their destination have to pay less. This is a counter-intuitive finding at first which arises from a trade-off with the earliness penalty of users who park close to the destination. We show that system optimality is also reached by redistributing the parking supply. Our numerical experiments capture the impact the autonomous vehicle penetration rate on the performance of the system and the proposed parking pricing and design strategies.

Design of Beam Position Fast-Correction Magnet Power Supply for HALS

Design of Beam Position Fast-Correction Magnet Power Supply for HALS

Design and Simulation for Pre-amplifier of ITER Radial X-ray Camera

The radial X-ray camera, which is used to measure magnetohydrodynamic phenomenon and monitor edge localised mode events, is a key diagnostic system for physics studies in the international thermonuclear experimental reactor (ITER) tokamak. Considering the special requirements of physics measurements and spatial resolution, 144 detector channels are required. The board card of the pre-amplifier is designed to improve the integration, on which 16 signal channels have been integrated. In order to suppress the noise and improve the stability of the pre-amplifier, the target impedance analysis method is applied in the design of the power supply, the trans-impedance amplifier and a two-stage active low pass filter are applied in the design. Simulation with Cadence OrCAD and ANSYS SIwave has been adopted to optimize the characteristics of the pre-amplifier. A test of the pre-amplifier shows its good performance for ITER application. After optimization of the pre-amplifier, the band width is 270 kHz, the amplification is 107 V/A, and the noise attenuation is − 30 dB, the noise of the pre-amplifier is reduced to 10 mV (noise of the power supply is included).

Design development and testing of high voltage power supply with crowbar protection for IOT based RF amplifier system in VECC

This paper described the detailed design, development and testing of high voltage power supply (−30 kV, 3.2 A) and different power supplies for biasing electrodes of Inductive Output Tube (IOT) based high power Radio Frequency (RF) amplifier. This IOT based RF amplifier is further used for pursuing research and development activity in superconducting RF cavity project at Variable Energy Cyclotron Centre (VECC) Kolkata. The state-of-the-art technology of IOT-based high power RF amplifier is designed, developed, and tested at VECC which is the first of its kind in India. A high voltage power supply rated at negative polarity of 30 kV dc/3.2 A is required for biasing cathode of IOT with crowbar protection circuit. This power supply along with crowbar protection system is designed, developed and tested at VECC for testing the complete setup. The technical difficulties and challenges occured during the design of cathode power supply, its crowbar protection techniques along with other supported power supplies i.e. grid and ion pump power supplies are discussed in this paper.

Optimization to water supply system design and operation scheme in high rise buildings

Greenhouse Gas emission from high-rise buildings has been increasing mainly due to excessive energy consumption of the HVAC system, structural system and electrical system. Electricity consumption for pump system accounts for 15% of total electricity usage in building. Therefore the reduction of electricity in operation is crucial to the overall reduction of GHGs in urban areas. In this study, a lab-scale experiment was conducted to test the electricity consumption in applying different design approaches; the energy efficiency of the system was calculated. Finally, this study proposes the advanced water supply design scheme to reduce electricity consumption of the pump system.
 Article history: Received 12 March 2018, Revised 03 April 2018, Accepted 27 April 2018

Advanced CFD modelling of air and recycled flue gas staging in a waste wood-fired grate boiler for higher combustion efficiency and greater environmental benefits

Grate-fired boilers are commonly used to burn biomass/wastes for heat and power production. In spite of the recent breakthrough in integration of advanced secondary air systems in grate boilers, grate-firing technology needs to be advanced for higher efficiency and lower emissions. In this paper, innovative staging of combustion air and recycled flue gas in a 13 MWth waste wood-fired grate boiler is comprehensively studied based on a numerical model that has been previously validated. In particular, the effects of the jet momentum, position and orientation of the combustion air and recycled flue gas streams on in-furnace mixing, combustion and pollutant emissions from the boiler are examined. It is found that the optimized air and recycled flue gas jets remarkably enhance mixing and heat transfer, result in a more uniform temperature and velocity distribution, extend the residence time of the combustibles in the hot zone and improve burnout in the boiler. Optimizing the air and recycled flue gas jet configuration can reduce carbon monoxide emission from the boiler by up to 86%, from the current 41.0 ppm to 5.7 ppm. The findings of this study can serve as useful guidelines for novel design and optimization of the combustion air supply and flue gas recycling for grate boilers of this type.

Design of a Hybrid Power Supply for a 65 T Quasi-Continuous High Magnetic Field With a Dual-Coil Magnet

A quasi-continuous high magnetic field is a special kind of pulsed magnetic field with a flat-top field longer than 100 ms. This paper proposes a hybrid power supply that consists of a capacitor power supply and a generator–rectifier power supply. A dual-coil magnet is powered to generate a 65 T/100 ms quasi-continuous high magnetic field with a ripple less than 500 ppm at the Wuhan National High Magnetic Field Center, Wuhan, China. A protection circuit consists of an R-C branch and a diode array is discussed for the worst short-circuit fault, which occurs between the first turns of inner coil and outer coil. This type of fault will produce oscillation voltage with a high peak value and high frequency on the rectifiers. A self-adaptive PI controller with the coefficients corrected by a back propagation neural network is adopted to reduce the ripple of a flat-top.

Superconducting Coil System R&D for a 230-MeV Superconducting Cyclotron

Started in January 2015, a 230-MeV superconducting cyclotron is under construction in the China Institute of Atomic Energy for proton therapy. A compact main magnet design with warm iron yokes and a superconducting coil system is adopted to reduce the size, construction, and operation cost of the cyclotron. In this paper, the field calculations of the main magnet are briefly described; then, the R&D of the superconducting coil system are outlined in detail, including the cryogenics design of the system, the forces, and stress analysis of the superconducting coil and support links, the power supply and quench protection design. Some preliminary test results are also presented.

REVERSIBLE VENTILATION SYSTEM FOR ADMINISTRATIVE BUILDINGS

Objectives To consider the possibility of applying the principle of reversing air flows for a centralised ventilation system; to develop a specific scheme for air exchange reversible ventilation, which will take into account the peculiarities of the microclimate of administrative buildings; to select the type of filling of the air-permeable element and justify this choice; to determine the conditions for changing the direction of air movement in the ventilation system and the area of its application; to form a list of equipment necessary for the operation of such a system; to consider the influence of supply and exhaust devices on the heat and humidity regime of claddings. Methods To achieve this goal, the published thematic material was reviewed and a patent search carried out using Russian and European databases. Data on mathematical modelling of filtration in porous media and experimental results were used. A method for ventilating rooms in administrative building using the reversal of movement of supply and exhaust air streams along the same channels was applied. Results Schemas for reversible ventilation systems are presented and their modes of operation considered. It is established that the idea of reversing ventilation flows has not yet been applied in the development of centralised ventilation systems. Based on these published materials, it was concluded that the proposed design of supply and exhaust devices can be used in practice. An original air exchange scheme for the ventilation of administrative buildings and design of supply and exhaust devices for this system are proposed. The conditions for changing the operating modes of the system and the scope of its application are determined. Conclusion The use of the proposed ventilation system allows normative air exchange to be provided without using a supply unit during the cold season. This application of airflow reversal allows the potential of natural forces to be used to the fullest extent to ensure the air exchange of the rooms.

The Sustainability of Integrating Contactless Occasional Charging in Electric Vehicle Material Handling

Electric mobility has developed itself to an option to mitigate air pollution and greenhouse gas emissions in cities same as in intralogistics material handling, while significant advances have been made in the research and development of electric vehicles (EV’s). Along with the major challenge of energy storage, another important factor is the efficient design of system energy supply, transfer and consumption. This has had the effect of fundamentally changing perspectives across the mobility and transportation sector.The overarching aim of this research is to examine the impact and potential of using contactless occasional recharging for non-road Electric Vehicles (nrEV) integrated within a manufacturing line, recognising the need to balance the (sometimes competing) demands of delivering reliable and efficient production while respecting environmental and sustainable needs. The integration of a contactless charging infrastructure targets on a reliable energy supply in process inherent break times without changing or interrupting existing production processes.The research investigations based on the Occasional Charging Station Location Model (OCSLM) provide a set of novel results in reference to the impact from interim battery charging to system`s overall sustainability. The application demonstrated a theoretical increase in usable battery energy of 40% to 60% while realising a reduction potential in battery capacity and system cost of between 5% to 45%. However, the use of contactless power transfer based on a standard energy mix resulted in an increase in CO2 emissions of up to 6.89% revealing a negative impact to overall ecology from the use of this energy transfer system.

Development of Magnetostrictive Transducer Prototype for Blockage Detection on Molten Salt Pipes

In solar thermal power plants molten salt is often used to store and transport the energy that is collected during the day. The external pipe temperature is measured to activate an electric heating system if the temperature approaches the melting point. However, salt solidification cannot be completely excluded from the plant management. Once occurred, the location of a salt blockage is very complex due to the high temperature of the pipe. Therefore, when this problem arises, power plants have to stop production with the consequences in time and cost that this entails. Electro-magnetic acoustic transducers can be used as non-destructive testing systems for this application. A method for salt blockage detection is proposed that is applicable in straight sections of pipes by employing torsional guided waves that are generated with magnetostrictive transducers. The present paper deals with the transducer conception and the design of the power supply to activate it. Two alternatives are proposed and compared to determine the improvement in the amplitude/noise ratio. Finally, the experimental results show the performance of the equipment in a small prototype, thus validating the technique presented.

Cultural Architecture for the Promotion and the Citizenization of Rural Population

With the rapid development of the society and the economy, the scale of urban construction has been continuously improved, and the service supply of the agricultural transfer population in the city has become a problem that must be solved. Based on this, the planning and design of the public cultural service supply and the urban integration of the agricultural transfer population were put forward in this paper. First of all, the background of the study on the cultural needs of the current agricultural transfer population was expounded, and the planning and design of the current urban public cultural service supply was discussed; then the design of public cultural architecture was put forward on the basis of meeting the demand of agricultural transfer population; with the public cultural and architectural project in a city as an example, the planning of urban parks and cultural and art centers was proposed to provide reference for promoting the integration of agricultural transfer population.

Planning and Design of Public Supply Services for Urban Integration

The citizenization of agricultural transfer population is the key content of urbanization. At present, the agricultural transfer population can't enjoy the same public service supply in urban integration. Based on this, in this paper, the planning and design of public service supply and the urban integration of agricultural transfer population were studied. The problems existing in urban integration of agricultural transfer population were analyzed, and the basic public service status of the agricultural transfer population in urban integration was expounded. Then, the basic public service needs of the agricultural transfer population in urban integration were analyzed, and the planning and design of urban basic public service supply were put forward. After that, taking the construction of the public service for agricultural transfer of population in a city as an example, a case analysis of the planning and design was carried out. The practice shows that the planning of urban public facilities service is beneficial to the urban integration of the rural population.

A Novel Self-Powered Lightning Current Measurement System

To address the lack of reliable power supplies for lightning current measurement systems (LCMS), this paper proposes a novel self-powered LCMS. The required operation power of a LCMS can be provided by harvesting the surge current that is measured using a power coil such that the system can be energized to complete a single-cycle measurement and data recording. In this manner, the stand-alone LCMS is triggered by lightning currents, and, hence, the signal acquisition can be activated automatically. In particular, this paper designs a two-channel passive peak-holding circuit as a low-power substitution to the conventional high-speed sampling modules. The polarity, current peak, and trigger time can be measured and ultimately be stored in a nonvolatile memory. The theoretical and simulation studies are presented in detail to determine the structure, size, and number of winding turns of the power and signal coils. The circuitry design of the power supply and signal conditioning units are also addressed. Experimental results verify that the proposed LCMS can accurately measure the amplitudes of lightning currents, achieving an accuracy of a maximum error of 4%, while the LCMS is fully self-powered to satisfy the energy demand from the measurement and data acquisition tasks.

Design of a Telemedical Vest for Sleep Disorder Diagnosis - A Preliminary Analysis

Abstract This paper presents the components of a sleep apnea analysis device that have been evaluated for diagnosis suitability and expected difficulties. The medical background and statistics of sleep apnea are presented. Work related to the topic is then discussed. A description of the system components follows: ECG, respiratory effort, nasal flow and pulse oximetry. Problems expected with all of these measurements are then outlined both from the methodological and electronic perspective. The main difficulties identified are the necessity to maintain the exact location of the sensors on the patient’s body and vulnerability of the sensors to variations of the environmental conditions. Challenges on the electronic aspect are then discussed, which are mainly caused by the need of measuring small signals (noise, interference) and compensation of the sensors’ nonlinearity. Power supply design in the context of the measurement accuracy is also considered followed by an evaluation of the impact of telemedical function presence. The paper ends with a summary and conclusions.

PWM power supply for ICRF ferrite tuner in EAST

Ion cyclotron resonance frequency (ICRF) heating is a traditional auxiliary heating method applied to EAST. However, the antenna load will oscillate violently with the change of plasma parameters in the ICRF heating. But fast ferrite branch technology (FFT) can be used to achieve real-time impedance matching by controlling the bias magnetic field of FFT to adjust its equivalent electric length. So an excitation coil power supply is developed to satisfy the requirement of fast and stable change of FFT bias magnetic field. In the power supply design, the method of Pulse Width Modulation is used to achieve rapid real-time conversion of current, and to meet the needs of rapid power conversion. The paper introduces general design of PWM power supply, front DC power supply, energy storage filter circuit and constant current circuit of H bridge sequentially. And an experiment is set on the FFT excitation coil current changing with the control signal, indicating that the rapid real-time current conversion can be achieved.

Direct Off-Line Two-Switch Forward Converter with a Boost PFC Converter for Powering of DC Electromagnet Systems

In this paper a switch mode power supply design for electromagnet systems is presented. It is based on a boost converter with power factor correction and a two-switch forward converter. The powered electromagnetic systems in this research are part of various electrical contact apparatus such as electromagnetic contactors, relays, circuit breakers etc. The proposed schematic works in a wide input voltage range which solve the problem with the voltage sag occurring in the energy distribution system. The proposed solution ensures stable operation of the contact equipment and the relay circuits in their industrial application.