Additional Power Source Research Articles

Paper-Based Batteries as Conductivity Sensors for Single-Use Applications.

We present a novel approach to measure ionic conductivity with a self-powered strategy. In particular, we propose the use of a paper-based battery as a sensor. The battery sensor unit consists of two electrodes placed side-by-side and covered by a piece of hydrophilic paper strip. The electrodes are externally connected to a resistive element. The addition of the fluid to be sensed—which acts as the electrolyte—activates the battery, which generates an output voltage that is dependent on the conductivity of the liquid sample. The device, which is conceived as a single-use disposable sensor, has been tested with different synthetic and biological liquid samples. The battery sensor effectiveness has been assessed by comparing its performance with a commercial laboratory conductometer. The device opens new avenues for conductivity monitoring in small portable and wearable devices, as it simplifies the number of electronic components and the need of additional power sources.

A fully batteryless multiinput single inductor single output energy harvesting architecture

Conventional energy architectures that utilize multiple ambient energy sources are initiated either by an external power supply or through the addition of an extra power source (e.g., battery) to the architecture. However, these interventions compromise the goal of a self-sustainable energy harvesting system. Moreover, conventional architectures are not effective in situations where space is limited (e.g., an artificial heart) or when access to this space is difficult (e.g., human implantable devices), due to their large battery size. Thus, conventional energy combiner circuits that use multiple energy sources are not well suited for supplying power to most applications. This paper presents a fully batteryless energy combiner architecture with a single inductor for the use of multiple ambient energy sources, including a solar cell and a microbial fuel cell. For each energy source, an auxiliary circuit (i.e. a charge pump) is implemented in order to provide a power supply to a digital control circuit, which consecutively connects each ambient energy source to a power converter. This novel architecture is completely self-starting and requires no additional extra power source or battery. This architecture has been designed and verified using a 0.13-$\mu$m CMOS process and a peak end-to-end efficiency of 79.33% for two ambient sources is achieved. This proposed system is applicable to numerous loads utilized in energy harvesting systems.

Nano Energy Generated By Microfluidic Flow

Energy harvesting is one of the most popular and important global issues for years. Through capturing or storing renewable energy, different energy-harvesting methods developed to provide additional power sources. In this work, a method to collect nano-scale energy by microfluidic flow was presented. Transferring microfluidic dynamic energy into electrical energy, we investigated the relationship between the extracted electrical current versus different electrode distances and the pH of an aqueous solution. The device was designed and implemented in a microfluidic channel with a gold-electrode grating. In the experimental testing, the flow rate was 300 μL/min. Based on the experimental results, the extracted output current was proportional to the electrode distance. The longer the distance (from 0.5 to 3 cm) was, the higher the output current (from 0.3 to 0.7 nA) obtained. In addition to the electrode-distance examinations, different aqueous solution with different pH value (from 5 to 10) were also investigated. To adjust the pH value of the solutions, hydrochloric acid (HCl) and sodium hydroxide (NaOH) were employed. In the pH-related experiments, the electrode distance was 3 cm and the flow rate was 300 μL/min. According to the experimental results, we can extract more electrical current (about 0.5 ~ 1.0 nA) with higher pH solution. In summary, this work demonstrated a potential method for energy harvesting. It could be used in different aqueous environment (ex. rain, river, marine etc.) or running water to generate current autonomously. This could be further integrated with applications of environmental monitoring.

Principles and methods of non-contact DC contactors calculation for alternative power systems

It is shown that the principle of control and power supply of a non-contact bi-directional DC contactor by the electrical line voltage is implemented by connecting the electronic control circuit by one output between two opposite powered gate-controlled thyristors of the bilateral switch to the first pole of the contactor and the second one – to the output clamp. As a result, the electrical line voltage is fed to the electronic circuit only for a short time (up to ms), that is determined by the charge time of the switching capacitor to the breakdown voltage of the threshold zener diode. The peculiarities of the heating process of the power semiconductor contactor in different operating conditions were determined, that allowed to develop a methodology that with sufficient accuracy determines such important parameters as rated and operational current of the contactor. In addition, it was found that in order to reduce significantly the capacity of the switching capacitor, and consequently the size and cost, it is necessary while turning on of the switching thyristor the discharging current of the switching capacitor was equal to the current of its charging circuit, and their values should not be less than the maximum allowable current of turning off the gate-controlled thyristor. It is allows to define justified the parameters of the elements that provide a secure turning off the bilateral switch. The researches have also shown that the non-contact contactors due to the introduction of the network voltage control as compared with existing ones have peculiarities which rise competitive abilities. In particular, they are more reliable, they do not need to supply an additional power source, they exclude standard drivers, and minimize energy consumption. Thus, an exemplary aspect of using the obtained scientific result is the ability to create competitive reliable non-contact DC contactors for voltage up to 1000 V and currents of 100-600 A for alternative energy. Key words – non-contact bi-directional DC contactor, switching capacitor, switching thyristor, power semiconductor switch, alternative energy.

Self-driven power management system for triboelectric nanogenerators

This paper presents a fully functional power management system for triboelectric nanogenerators (TENGs) with the TENG as the only power source. TENG was developed for the objective to provide power to electronic devices and sensors without the need for a battery (the so-called self-powered systems). A unique feature of the TENG's electrical output is high pulsed voltage but low current capability, making TENGs unsuitable for direct use as a power source. To provide continuous and steady electrical voltage for conventional electronics, a power management system (PMS) is required. Existing PMS′ based on power electronic converters do not provide a complete solution due to the use of additional power sources for the logic circuit and switch drivers. The PMS to be reported in this work provides a complete solution for a self-powered system with the TENG as the only power source. This goal is accomplished with a novel approach of employing discrete semiconductor devices, including a silicon-controlled rectifier (SCR) and zener diodes, for controlling the power flow paths, without using any integrated circuit. The effectiveness of the newly developed PMS has been experimentally validated with a prototype and a contact and separation mode TENG device.

Boosting Microbial Fuel Cell Performance by Combining with an External Supercapacitor: An Electrochemical Study

AbstractMicrobial fuel cells (MFCs), despite representing a promising technology, suffer from low power generation that hinders, in most of the cases, their application as power sources. In fact, MFCs are usually coupled with supercapacitors or batteries and these storage units accumulate the energy harvested by MFCs and deliver it on demand. In this work, the electrodes of a MFC are used as electrodes of an internal supercapacitor and discharges and self‐recharges are performed and investigated. Discharges between 1.5 mA and 4 mA were presented producing a maximum power of 1.59 mW. Discharges between 1 mA and 100 mA and recharges are systematically studied for three commercial supercapacitors (SCs) with different capacitances of 1 F, 3 F, and 6 F. The MFC was also connected in parallel with external SCs and discharged galvanostatically. The SC was self‐recharged by the MFC without any additional external power sources. At lower current pulses, the MFC contributed to the overall capacitance, probably owing to its faradaic component. At higher current pulses, the use of SCs enables the energy to be harvested by MFCs at power levels that could not be achieved with the MFC alone. This study demonstrates that, through the proper connection and operation mode of the MFC and SC, it is possible to improve and maximize the performance of every single unit. Understanding the MFC−SC combination is important for identifying the right practical application for which the combination is suitable.

Measurement of Impedance-Frequency Property of Traction Network Using Cascaded H-Bridge Converters: Device Design and On-Site Test

To investigate the harmonic resonance in electric railways, determination of the traction network impedance using a utility instrument is an important and challenging task. This article presents a novel industrial test device which can directly measure the impedance of the actual traction network which is the power source of the railway. The structure arrangement and the parameter design are accomplished to meet the requirements for high-voltage level and strong anti-electromagnetic interference capability. Following this, frequency-dependent impedance measurement is implemented through the injection of controlled harmonic currents using the cascaded H-bridge converters. Furthermore, the power flow analysis is carried out to demonstrate that this device does not need any additional power source and can generate harmonic power. In a new-built railway, this device has been adopted to conduct the on-site test of the traction network impedance. Then, the multi-conductor simulation model is established for the purpose of mutual verification between the field test result and simulation result. Furthermore, the on-site test results can be applied to determine the resonance frequency before a nenw-built line is put into use so that any harmonic resonance can be avoided by taking effective measures in advance.

Perspective of solar energy-powered road and rail transportation in China

As essential pillars of passenger mobility and freight transport, road and rail transportation have experienced a rapid increase over the past years. This trend indicates an increase in energy consumption, especially electricity, due to higher energy efficiency and less carbon emission, but it exacerbates the contradiction between the power supply and demand. Nowadays, for additional power sources, increased solar power generation has been widely installed in their own available spaces for road and rail transportation, which has attracted a great deal of attention. This paper reviews the current status of solar power generation and its integrated application in the transport sector. Then, the photovoltaic generation potential of road and rail transportation in China are evaluated. Finally, further developments and perspectives of solar energy-powered road and rail transportation are presented, which not only contributes to lower-carbon and green transportation, but also promotes the development of renewable power generation for energy transformation. It is confirmed that solar energy-powered road and rail transportation is a promising approach for sustainable transportation with more renewable energy and less carbon emission.

OPTIMIZATION OF THE CONVERTER CHARACTERISTICS IN BRAKING TRANSITION MODES OF TRACTION ENGINE

Described conditions of converter optimization for DC engine braking modes. Braking minimizes the level of current ripple when using various methods of current regulation. Solving problems of efficient use of a DC traction engine and create safe modes of operation by ensuring optimal mode. The introduction of additional elements in the scheme allows to reduce the rate of attenuation of the current in the brake coils. A significant advantage of the proposed circuit modernization is the introduction of diodes in the circuit, which will allow the use of self-excitation of the electric motor for electrical braking. The proposed solution simplifies the technical implementation and reduces costs due to the lack of an additional independent power source for the brake coils. A significant factor in increasing the profitability of electric transport in general may be the replacement of an existing traction electric drive (TEP) with their more modern types. Simulation models have been developed to allow the study of electromechanical processes in a serial DC engine. Introduction to the circuit of a pulsed regulator diode, which shunts the excitation winding, reduces the rate of attenuation of the current in this winding. The proposed modernization of the circuit is to introduce into the circuit the diodes, an energy storage, which allows the use of brake modes for self-excitation of the motor and to avoid the use of additional independent sources of current.

APPLICATION OF THE AUTOMATIC CONTROL THEORY FOR SEARCHING RATIONAL WAYS OF TECHNICAL DIAGNOSTICS AND IMPROVEMENT OF TECHNICAL CHARACTERISTICS OF 2E36 STABILISER

The subject matter of the article is the process of troubleshooting a BMP-2 fire control system The goal of the study is the developing a fault finding algorithm in this system and to offer suggestions for improving the technical characteristics of the weapon stabilizer based on the analysis of design and circuit solutions and technical characteristics of the BMP-2 fire control system. The tasks to be solved are: to conduct an analysis of the BMP-2 fire control system as a closed automatic control system provide suggestions for improving the performance of the stabilizer; to draw up a block diagram of a rational technical diagnostics of the 2E36 stabilizer and to propose a method for troubleshooting.General scientific and special methods of scientific knowledge are used. The following results are obtained. It is proposed to improve the technical characteristics of the 2E36 stabilizer by reducing the number of gyrotachometers from four to two with a parallel increase in the remaining signal branching, as well as improving the speed characteristics by installing an additional power source - a capacitor battery, for short-term and short-term engines. A rational technical diagnostics block scheme of the 2E36 stabilizer has been drawn up and methods of troubleshooting in the form of rigidity tuning cards, damping and vibration of the gun and turret stabilizer have been proposed. The diagnostic methods of elemental and group inspections are analyzed. Based on the analysis, the basic algorithms for the diagnostic process of tower and gun stabilization were developed. Thanks to this in the area of the task, personnel and repair units will be able to ensure the combat readiness of the equipment as quickly as possible. Conclusions. Gun stabilizers and turrets are closed automatic control systems based on the principle of adjusting the deviation of the adjustable value from a predetermined value. The objects of regulation in these stabilization systems are the cannon and the tower, and the adjustable values are their angular velocities. Feedback optimization involves reducing the number of gyro tachometers from four to two, which will increase the power reserve and give more opportunities for further stabilizer upgrades. Acceleration of the accelerator of the executive motor can be accomplished by installing a capacitor battery. The most long-term step in the process of repairing the complexity of complex systems is the process of finding failed items. The scheme of rational technical diagnostics provides the basic algorithms for carrying out the diagnostic process of stabilization of the tower and the gun, which allows to search for problems with maximum efficiency.

Implementation of Dual-Circuit System for Additional Power Supply Based on Photovoltaic Converters for Electric Vehicles

The article presents a process of designing the photovoltaic (PHV) converters system for an electric vehicle, shows the scheme of photovoltaic converters usage, the results of electric vehicle motion modeling with photovoltaic converters, and the results of road tests of an electric vehicle with an additional power source based on photovoltaic converters. The photovoltaic converters system and low-voltage system of an electric vehicle have a shared low-voltage battery, which allows the implementation of two schemes of electric vehicle power supply. Initially, the aggregate base was selected, then, taking into account the efficiency of each device included in the design of the new electric vehicle, mathematical modeling was carried out and showed good efficiency results of the photovoltaic converters system. Then, the prototype was manufactured and tested. The aggregate base included the battery of photovoltaic converters assembled in a certain way on the vehicle roof, the MPPT (maximum power point tracking) controller, the buffer storage device in the form of a 12 V battery, and the DC (direct current) converter that allows transmitting electricity from the buffer battery to the high-voltage system. Modeling of the electric vehicle motion considered typical operating modes, including energy costs for the operation of assistant systems of the electric vehicle, as well as including the consumption of low-voltage components. The tests were carried out according to the NEDC (New European Driving Cycle). As a result, implementation of photovoltaic converters with 21% efficiency allowed for the power reserve of the electric vehicle to be increased by up to 9%.

Development of strategies for reducing traction energy consumption by electric rolling stock

The paper considers a method of increasing the energy efficiency of the traction power consumption during operation of a non-autonomous electric rolling stock equipped with an onboard energy storage. The idea is to use the onboard energy storage of the electric braking as an additional power source for the traction electric drive in the process of vehicle acceleration and to coordinate its work with the power supply system. This not only ensures the independence of the processes of electric power consumption and kinetic energy recovery by the traction equipment, but also reduces losses in the elements of traction and external power supply systems. To confirm the effectiveness of the proposed method, we simulated the operation of a metro train with asynchronous traction electric drive in combination with the proposed system. The results obtained, in this case, demonstrated a reduction of energy losses in the elements of the traction power supply system during the electric train acceleration by 45 % compared with the losses when using a regular traction drive system. Attention is paid to the factors and their characteristics that exert significant influence on the traction and electric braking processes.

Features of operation of wind power stations as an supplementary source of electricity for non-traction consumers of railway electric mains

Purpose. Identify the features of operation of wind farms as an auxiliary supplier of electricity for non-traction consumers of railway networks and analyze the main factors that directly affect the use of wind farms due to the random nature of wind flow and additional factors due to the above conditions in different climates. The research methodology is based on modern methods of computational mathematics, statistics and information analysis using modern computer technology. Findings. The need to use renewable energy sources in the power supply systems of non-traction consumers of railway transport is obvious. Given the constant growth of prices and tariffs for electricity in Ukraine, more and more attention is paid to its savings and the search for the cheapest and most affordable alternative sources. The authors consider issues related to the possibility of using additional generation of electricity in the power supply systems of railway transport through the use of wind turbines, including for non-traction consumers. The analysis of wind flow features in some regions of Ukraine was carried out, and the measurement of wind speed in Zaporizhia and Dnipropetrovsk regions was obtained with the help of a compact wind speed sensor manufactured by Micro-Step-MIS LLC (Russia). The obtained values of wind speed were recorded and stored digitally. The received information of the above device was processed. The authors conclude that in the case of using wind turbines as an additional power source in the networks of non-traction consumers of railway power supply systems it is economically advantageous to connect them directly to these networks and fully use all electricity produced by them, reducing its consumption from this power supply system. The originality is that the use of renewable energy sources in the power supply systems of non-traction consumers of railway transport, in particular wind turbines, is proposed. Practical implications. Introduction of wind power plants as an auxiliary supplier of electricity for non-traction consumers of railway power grids in order to minimize electricity costs. Keywords: renewable energy sources, quality of electric energy, wind power plant, power supply networks of railway transport, non-traction consumers of railway electric networks, electricity production, wind speed.

Кинематический накопитель энергии для децентрализованной энергетики

In mastering the use of decentralized renewable energy sources, problems of connecting them to the common grid are encountered, including those stemming from the nonuniform power output produced by them. The use of a kinematic energy storage (KES) as an additional source of power for a wind farm is considered. In addition, a high-speed three-phase permanent-magnet synchronous machine equipped with an output electronic module, with which the energy storage can operate with a variable rotation frequency, is proposed to be used as the KES motor—generator unit. The parameters of a KES with the inertia moment equal to 100 kgm[1] made using different materials (steel, aluminum, titanium, and high-strength composite material) have been calculated for different flywheel diameter-to-height ratios. It is shown that the energy storage equipped with a 624-kg flywheel made of composite material can produce the power output equal to 5 kW for 8 h in the rotation frequency range 18000—6000 min-1. A three-phase permanent-magnet motor-generator is proposed for such KES.

Principles of constructing, calculation methods of direct current hybrid contactors for alternative energy

is shown that the principle of control and voltage supply of the hybrid DC contactor network is realized by connecting the electronic circuit with one terminal between two counter-actuated power-operated semiconductor devices of the two-way key, which shunts the main contacts of the first pole of the contactor, and the second terminal Luce. As a result, the network voltage is fed to the electronic circuit only for a short period of time (several ms), which is determined by the value of the time flow of the load current through the shunted bidirectional NC under the disconnected load. The features of the process of current flowing from the main contacts to the circuits of switching on and off power controlled devices and the charge of the switching capacitor are determined. It was found that in order to ensure reliable switching in the entire range of switching currents of the contactor, it is necessary that the parameters of the elements of the switching circuit and the charge circuit of the switching capacitor were selected on the condition that the current in the switching circuit of the power NC at the moment of its switching was equal to the current in the charge circuit of the switching capacitor. In this case, the value of this current should not be less than the maximum switching-off current of a fully controlled NC. This makes it possible to reasonably approach the determination of the parameters of the elements, which ensure the secure locking of the two-directional NC. As a result of the studies, it was also shown that the proposed hybrid contactors due to the introduction of voltage control of the network compared to the existing ones have competitiveness enhancing properties. In particular, they increase the reliability of the work, they do not need to supply an additional source of power, they exclude standard drivers, minimize energy consumption. Thus, an exemplary aspect of using the scientific result obtained is the ability to create competitive on-line hybrid DC contactors with a voltage up to 1000 V and currents of 100 ÷ 600 A for alternative energy.

Solar car: modern technologies and development prospects

Problem. At the present time, the need for energy sources is growing. The use of petroleum products as energy sources leads to environmental degradation. It is necessary to look for alternatives to heat engines, which are the main sources of air pollution and exhaustion of natural resources. One of the ways to solve this problem is to use solar energy. Solar cars harness energy from the sun, converting it into electricity. Goal. Analyzing the existing types of cars with alternative power sources. Explore solar cars. Examine their device. To determine all the advantages and disadvantages of this invention. We give a forecast on the prospects for the development and use of the cars on solar energy. Results. The device of the heliomobil is investigated; the principle of its work is studied and generalized. The advantages and the indicated disadvantages of these vehicles are given. We analyze all the positive and negative aspects of this invention. There is the problem of how to get around at night or on rainy days when the sun is nowhere to be seen. Most viable solar car projects rely on additional power sources to ensure that the car gets going any time you need it to. Originality. The main indicators that influence the development of production and use of solar cars in the future are shown in this article. It is reasonable to use solar vehicles in the present and especially in the future. Practical value. It can already be argued that for heliomobiles there is an ecologically clean future of our planet. The use of solar energy is a step towards improving the ecology of our planet. Solar cars will be crucial to reducing transport’s impact on climate change and should be introduced widely as soon as possible.Keywords: heliomobile; electric car; photocells; photoelectric effect; solar battery.

Electron aspirator using electron\u2013electron scattering in nanoscale silicon

Current enhancement without increasing the input power is a critical issue to be pursued for electronic circuits. However, drivability of metal-oxide-semiconductor (MOS) transistors is limited by the source-injection current, and electrons that have passed through the source unavoidably waste their momentum to the phonon bath. Here, we propose the Si electron-aspirator, a nanometer-scaled MOS device with a T-shaped branch, to go beyond this limit. The device utilizes the hydrodynamic nature of electrons due to the electron–electron scattering, by which the injected hot electrons transfer their momentum to cold electrons before they relax with the phonon bath. This momentum transfer induces an electron flow from the grounded side terminal without additional power sources. The operation is demonstrated by observing the output-current enhancement by a factor of about 3 at 8 K, which reveals that the electron–electron scattering can govern the electron transport in nanometer-scaled MOS devices, and increase their effective drivability.

An Accurate Force Regulation Mechanism for High-Speed Handling of Fragile Objects Using Pneumatic Grippers

Controlling the gripping force on fragile objects has been a challenging task for industrial grippers. The solution often requires an electric gripper with embedded force sensors and control feedback. This approach is costly and leads to extra gripper complexity. To avoid damage while handling fragile objects, this paper presents a novel force regulation mechanism (FRM) to be installed on pneumatic grippers. Without using additional sensors and control, the FRM can passively produce an adjustable contact force between the gripper jaws and objects of various sizes. Together with pneumatic grippers that have a higher gripping speed, lower cost, and simpler structure, this approach offers a more attractive solution than the use of electric grippers. In this paper, the design and analysis of the FRM are presented. A prototype of the FRM is illustrated to demonstrate the effectiveness and accuracy of force regulation. This novel mechanism is expected to serve as a reliable alternative for fragile object manipulation. Note to Practitioners —Pneumatic grippers are popular due to their low cost and simple structure. However, it is difficult to control the gripping force to handle fragile objects without damage. The FRM has a small size and can be easily installed on pneumatic grippers to provide fast force regulation. The gripping force depends on axial preload of the FRM rather than air pressure of the gripper. Axial preload is passively regulated using a screw or spacer. No additional source of power or sensor is required. The FRM has a large force adjustment range and can grip objects of various sizes using the same force. Applications include the automation in electronics, food, agricultural, and medical industries.

Digitally Assisted On-Chip Body Bias Tuning Scheme for Ultra Low-Power VLSI Systems

Body bias control is one of the most efficient means to reduce leakage power, adjust process variation, and apply performance boost. However, such control incurs a certain power overhead that has to be reduced, especially in ultra low-power systems. In order to exploit the advantages of body bias control while guaranteeing power efficiency, an on-chip control scheme is required. Conventionally, on-chip body bias control relies on the use of digital–analog converters. However, such analog circuits require a high power supply voltage and an additional power source, resulting in a considerable power overhead and an increased system cost. In this paper, an on-chip “Digitally assisted Automatic Body-bias Tuning” (DABT) scheme for ultra low-power systems is proposed and evaluated. The proposed scheme controls the body bias voltage so as to meet the timing constraints of a given target system. Since DABT is based on “Digitally assisted” circuitries, it can decrease the power supply voltage to near-threshold region and, therefore, a significant amount of power overhead can be reduced. The proposed system is fabricated with the 65-nm silicon on thin box (SOTB) process, a fully depleted silicon on insulator technology. We demonstrate that the chip can achieve the expected functionality, even with 0.35 V of power supply voltage, and with only a few micro watts of power overhead. Moreover, the efficiency of the proposed system is evaluated with a MIPS processor, adopted as a case study. According to the obtained evaluation results, the proposed system can enable 80% of leakage reduction while maintaining the frequency required to meet the timing constraints of the adopted target MIPS processor.

Load-Sensing Pump Design to Reduce Heat Generation of Electro-Hydrostatic Actuator Systems

The electro-hydrostatic actuator (EHA) with variable pump displacement is considered to be a promising alternative to the currently popular EHA with fixed pump displacement in terms of heat reduction. This paper presents a load-sensing pump for the EHA which requires no additional power source and can adjust its volumetric displacement automatically with load pressure. A load-sensing pump prototype was developed and experiments were carried out on a test rig for it under different operating conditions. In addition, an experimental campaign was performed on an EHA test bench with a load-sensing pump and a fixed displacement pump. The results show that the load-sensing pump can decrease its volumetric displacement automatically at high pressure and thus reduce the heat generation of EHA system effectively.