Independent Power Supply Research Articles

Thrust ripple suppression analysis of moving-magnet-type linear synchronous motor based on independent coil

In this paper, a novel thrust ripple suppression method for multi-secondary permanent magnet synchronous linear motor based on independent coil structure is proposed. Independent coil structure can realize independent power supply for each coil by changing the driving mode of the coils. Combined with the new power supply strategy, the detent and electromagnetic force fluctuation can be suppressed. Firstly, the cogging and end force of moving-magnet-type linear motor are separated by periodic and vector boundary conditions and harmonic analysis is carried out. An analytical model of air gap magnetic field based on virtual magnetic poles is established to solve the back EMF and electromagnetic force fluctuation of the motor. The generation mechanism and harmonic of electromagnetic force fluctuation are analyzed. A multi-secondary PMLSM based on independent coil is proposed, the principle of suppressing motor thrust ripple is expounded, and the coupling effect between modules is analyzed. Finally, a zero-crossing power supply strategy is proposed. The simulation and experimental results show that multi-secondary independent coil PMLSM can effectively suppress the detent and electromagnetic force fluctuation.

DEVELOPMENT OF SCIENTIFIC FOUNDATIONS AND METHOD OF AUTONOMOUS POWER AND GAS SUPPLY OF REMOTE CONSUMERS FROM GAS DISTRIBUTION NETWORKS

The development and implementation of independent power supply systems with a high degree of autonomy is becoming an urgent task for the development of remote and inaccessible regions of the country, both due to the lack of energy capacities and accessible networks in newly developed areas, and the high cost of allocating separate power lines for remote and compact settlements. The increase in the scale of central networks is associated with high capital investments and long project implementation time, which creates inconvenience for consumers and the development of small and medium-sized enterprises. At the same time, unlike power supply, gasification issues, which are actively being resolved in all regions of the country, make it possible to connect new consumers of natural gas several times faster and cheaper, which is due to the high manufacturability and speed of construction of polyethylene gas pipelines of distribution networks, provided that gas pipelines pass in the region. In addition to lower capital and operating costs, the process of transporting energy resources through pipelines in the form of a primary source — gas — is characterized by significantly lower losses compared to water and electricity. At the same time, network gas in combination with trigeneration technologies and cryogenic hydrocarbon storage can be used not only as boiler fuel, but also as motor fuel, a source for generating electricity, heat and even cold with a replenished autonomous reserve. Thus, as an alternative solution to traditional power systems, it is proposed to use hybrid power systems — systems based on trigeneration plants with gas piston installations, turbine and screw machines, as well as cryogenic gas storage facilities that can provide the population with electricity, heat, cold and motor fuel. The article analyzed the state and development of the fuel and energy complex in Russia, conducted a study of the needs for heat, gas and electricity for an average compact settlement with small and medium-sized enterprises. Analysis and selection of equipment parameters for uninterrupted autonomous power supply of the economy was carried out.

Distributed Photovoltaic Site Selection and Capacity Planning Considering Power Mutual Support in Multiple Power Distribution Areas

Abstract With the rapid development of local economy, the form of independent power supply from a single power supply in the power distribution area is difficult to meet the demand for high reliability. The interconnection and power mutual assistance planning of power distribution areas under large-scale distributed photovoltaic access have attracted widespread attention. Due to the randomness and volatility of distributed photovoltaics, its different access methods and capacities will affect the safe and stable operation and power mutual assistance capabilities of the distribution area. In order to study the site selection and capacity planning problem of distributed photovoltaics, this paper builds a site selection and capacity model based on the three-phase power flow equation with the maximum external power of the station area as the optimization goal and the safe operation of the distribution area as constraints. Furthermore, an optimization method for distributed photovoltaic site selection and capacity based on improved particle swarm algorithm is proposed. Finally, this paper verified the effectiveness of the optimization method through simulation analysis on the IEEE33 three-phase grid model. The simulation results show that this method of site selection and capacity determination can achieve maximum power transmission in the power distribution area while ensuring the safe and stable operation of the area.

Micro-electricity generation from wind-induced vibration with magnetostrictive material-based energy harvester

This study aimed to experimentally investigate flow-induced vibration of modified circular cylinders for wind-receiving mast of Vibration-Based Power Generator (VBPG). Specifically, it focused on vibration characteristics of tapered and stepped circular cylinders in VBPG mechanism. Tapering and inverting cylinder model proved effective in reducing Vortex-Induced Vibration (VIV) onset and peak amplitude concerning flow stream velocity. Some tapered cylinder models showed a broadening peak response (upper branch region), showing an extensive power harvesting range for VBPG device. The result showed that the maximum power harvesting of the model with a plain bluff cylinder was 8.45 mW, reduced by tapering bluff cylinder. The power coefficient of VBPG with a normal bluff cylinder was 4 %, but inversing stepped bluff cylinder yielded 5.45 %. It is related to VIV-onset parameter, which was lower than that the plain cylinder. In addition, it was discovered that there was an interdependency between frequency response and power generation capacity for VIV-type resonance. The generated power proved sufficient to illuminate a board with 54 LED lamps in a laboratory-scale test. Meanwhile, an outdoor performance test of harvester, conducted with variable wind speed (0 – 3.2 m/s), showcased the reliability of VBPG mechanism for independent power supply to wireless, remote sensor networks, or moderate scale of power supply. The field test model worked not only in variable wind speed, but also in chaotic wind direction.

Fuzzy sliding mode control with adaptive exponential reaching law for inverters in the photovoltaic microgrid

Photovoltaic inverters are widely utilized in microgrid systems working as the key equipment for converting solar energy into usable electricity. This paper presents a fuzzy sliding mode control (FSMC) method for the photovoltaic inverter in a microgrid. The inverter module uses voltage control to achieve stable AC output voltage. Moreover, to deal with system uncertainty and non-linearity in the photovoltaic inverter, a fuzzy controller was designed to realize real-time adaptation of the gains of the constant term and the reaching term in the sliding mode control law, which serves as a compensating controller for traditional sliding mode control. The gains of the exponential reaching law can be adjusted according to the system state instead of fixed gains, which can effectively reduce the chattering phenomenon and improve the robustness of the photovoltaic microgrid. Finally, the Lyapunov stability theory was used to ensure the stability of the entire control system, achieving a high-performance independent power supply for loads in a microgrid. Simulation results show that the designed control system is more robust to load disturbances and has superior dynamic performance.

CONCEPT SOLUTION OF AUTONOMOUS IOT SMART HIVE AND OPTIMIZATION OF ENERGY CONSUMPTION USING ARTIFICIAL INTELLIGENCE

In this paper the authors present a conceptual solution for an autonomous smart beehive with a focus on energy efficiency; the hive's existence is based on artificial intelligence. The hive is equipped with an advanced system for monitoring the entry and exit of bees, as well as for collecting data on the weather inside and around the hive. Using an array of sensors controlled by Espressif ESP32 and Arduino Mega microcontroller boards, the hive continuously optimizes the operation of the ventilation system and other components, monitoring energy consumption and adapting to changing conditions. Special accents in the work are dedicated to the monitoring of the solar panel and, consequently, the capacity of the battery for independent power supply of the system, as well as the application of artificial intelligence to predict meteorological changes and optimize energy efficiency. This paper provides a comprehensive overview of the solutions and technologies that enable the autonomous and energy-efficient functioning of the Smart Hive.

Modelling and simulation of Λ-ridge concentrator system using commercial PV modules

This paper presents the Λ-ridge and V-trough concentrator system with low concentration ratio applicable in independent power supply systems (e.g. chalets, road signs, traffic lights, street lamps, industrial cameras, CCTV), of an outpower not exceeding 500W. Actual area of photovoltaic modules, which doesn’t exceed 3m2 constitutes important parameter in this kind of construction. Small external dimensions and relatively light weight are the crucial principles of constructing Λ-ridge concentrator system. The performance of the system and the amount of energy produced constitute key factors for such restrictions. A series of simulations was conducted enabling evaluation of the efficiency of the presented systems depending on their technical parameters and weather conditions.

Study on the Change of Power Consumption Structure in Xumai Township, Nimu County, Lhasa, Xizang

The research on the evolution of rural power consumption structure in Xizang reflects the information on rural power development in Xizang, and the information on rural power development shows the people's living standards and demand trends. In order to understand the depth of changes in the power consumption structure of farmers and herdsmen households, the project team conducted a field survey of the changes in power supply sources, power consumption structure, power consumption equipment, and operation and management status of Sumai Township, a typical village in Nimu County, Lhasa City, Xizang over the years, and explored the history and trend of power development in remote villages in Xizang. Field research has found that before 2014, the township mainly relied on small-scale independent solar photovoltaic power supply, which was almost used for lighting; Since the implementation of the State Grid in 2014, electricity consumption has shifted from low voltage to wide voltage. In the past three years, the annual electricity consumption growth rate in Xumai Township has exceeded 6%, and the power supply stability has reached 90%. At the same time, the township utilizes solar photovoltaic street lights. The electrical appliances used have developed from a single lamp to power appliances such as household appliances, agricultural electric vehicles, tsamba machines and oil presses. The distribution line of the township is gradually being replaced with medium and low voltage, and is equipped with a 35kV Xumai substation. The 10kV medium and low voltage distribution network project of the rural power grid is gradually being put into operation and put into practice. However, research has found that villagers hope to use more clean energy such as solar energy for power supply and heating, in order to reduce the cost of electricity and gas bills.

Design and Control of Hydraulic Power Take-Off System for an Array of Point Absorber Wave Energy Converters

The development of wave energy converter (WEC) arrays is an effective way to reduce the cost of levelized energy and facilitate the commercialization of WECs. This study proposes a hydraulic power take-off (PTO) system for an array of point absorber wave energy converters (PA-WECs) and designs a control system using a novel algorithm called the improved simplified universal intelligent PID (ISUIPID) controller and the adaptive matching controller including an improved artificial gorilla troops optimizer (IGTO) to improve and stabilize the output power of PA-WEC arrays. Simulations under varying irregular wave states have been carried out to verify the validity of the mathematical model and the control system. The results show that the designed IGTO has faster convergence speed and better convergence accuracy in solving the optimal linear damping coefficient of the generator, and the proposed ISUIPID controller provides superior performance in tracking the speed of the hydraulic motor under the changing sea states. In addition, the capture power and output power of the array of PA-WECs are improved and the electrical energy can be output stably under the designed control system. The array of PA-WECs with the proposed control system will become an independent, stable, efficient, and sustainable power supply system.

Analysis of the Wireless Power Transfer System Using a Finite Grid of Planar Circular Coils

In this paper was analysed a wireless power transfer system (WPT) with multiple resonators supplying, for example, sensors or LED lighting. Energy is transferred simultaneously using a group of identical planar spiral circular coils acting as transmitters and receivers. These coils were arranged to form transmitting and receiving planes. The receivers were connected to independent power supply circuits of each, e.g., sensor or LED lighting. Higher power reliability and flexibility can be achieved by isolating these circuits. The proposed system was described and discussed. Taking into account the skin effect and mutual couplings, a theoretical analysis was made. A detailed analysis was made at the resonant frequency of the system. The system was modeled using a matrix equation and appropriate formulas. The calculations were verified experimentally for different loads and two distances between transmitters and receivers. The efficiency and receiver power were compared and discussed. The maximum efficiency was about 45% at the small distance between the planes. The maximum efficiency of the WPT system decreased more than two times to less than 20% when the distance between the coils was doubled. The results and discussion of the conducted analysis may provide valuable knowledge when designing this type of system.

Boosted electrocatalytic oxidation of organophosphorus pesticides by a novel high-efficiency CeO2-Doped PbO2 anode: An electrochemical study, parameter optimization and degradation mechanisms

This article presents a novel and highly efficient electrocatalytic degradation method for two significant organophosphorus pesticides, fenitrothion (FEN), and methyl parathion (MPN), using a Ti/β-PbO2-CeO2 modified anode (indirect oxidation). A comprehensive electrochemical investigation was also carried out to gain new insight into the redox behavior and destruction pathway of these pesticides (direct oxidation). The study also explores the effects of various operating parameters, such as initial solution pH, applied current density, and initial pesticides concentration, on the conversion-paired electrocatalytic removal process. To further enhance the degradation efficiency, a new configuration of the electrochemical cell was designed, employing two types of electrodes and two independent power supply devices. The conversion paired electrocatalytic degradation process of these pesticides involves first the direct reduction of FEN (or MPN) on a graphite cathode and then the indirect oxidation of reduced FEN (or MPN) by hydroxyl radicals electro generated on the Ti/β-PbO2-CeO2 anode. The synergism of these two processes together will effectively lead to FEN (or MPN) degradation. The degradation percentages of 98% for FEN and 95% for MPN at the optimal conditions for the electrochemical degradation of these pesticides were achieved at pH = 7, initial concentration 50 mg L−1, with a current density of 90 mA cm−2 for direct reduction and 11 mA cm−2 for indirect oxidation. Overall, this study presents a promising and efficient approach for the remediation of organophosphorus pesticide-contaminated environments, offering valuable insights into the electrochemical degradation process and highlighting the potential for practical application in wastewater treatment and environmental protection.

All-transparent tandem photovoltaic-powered photodetector

Can electronics operate independently and invisibly in designated places? If yes, the user would not recognize the existence of devices and this can be applied to various applications. The device should be optically transparent and simultaneously achieve transparent electric power to satisfy this invisible freedom. Herein, we propose a dual transparent platform consisting of a broad-range translucent photodetector powered by an invisible photovoltaic unit. Transparent photovoltaic (TPV) has a NiO/TiO2 heterojunction for high optical transparency of 79.7% and can produce a maximum voltage of 0.6 V at an efficiency of 13.4%. A transparent broadband photodetector (TBD) that comprises Co3O4/ZnO has high optical transparency (70%) and provides a broad wavelength photodetection. The TBD can be tuned in the reverse bias mode along with the separate power unit (TPV), which significantly enhances the responsivity to 6.8 mA W−1. In contrast to the self-powered operation mode, the dual system (TBD and TPV power units) can actively control the bias voltage to the TBD, supplied from the TPV (0–0.6 V). TPV and TBD have an overall transparency of 56.4% and long-term stability to allow a high degree of freedom in transparent human electronics, ensuring visional transparency and an independent power supply.

A novel high-performance three-phase magnetic field energy harvester for powering up vehicle onboard electronics

The boosting development of vehicle electrification and onboard sensing networks in the intelligent vehicle era poses a significant challenge to conventional electrical power supply systems. This study developed a novel passive three-phase magnetic field energy harvester (TMEH) for reliable and sustaining power to drive vehicle onboard electronics, which recycles the induced magnetic field energy around the power lines of a permanent magnet synchronous motor (PMSM) on an electric vehicle (EV). A Y-Y topological connection pattern for three-phase coils was designed to enhance and stabilize the TMEH output performance. Furthermore, three auto-shift operating modes were assigned to the TMEH to tackle the dynamic changes of the captured power caused by unpredictable vehicle manoeuvres and road conditions. The theoretical model and numerical method were also established for structural optimization of the TMEH, followed by a series of experimental tests for highlighting the impacts of the power lines carrying alternating current on TMEH. The results have indicated that the proposed TMEH showed impressive energy conversion efficiency, providing an independent power supply for sensors and other electronics applications on a 4 kW-PMSM driven EV. Bench testing results and practical EV driving trials demonstrated the capability of the TMEH prototype to power up multiple types of sensors and electronic devices under most EV driving conditions. Specifically, an average power of 5.69 W and power density of 123.85 mW/cm3 were generated by the harvesting coils when excited by a 50 A current at 50 Hz. Furthermore, the maximum TMEH energy conversion efficiency of 41.9% at the excitation current frequency of 50 Hz is obtained in laboratory conditions. In EV driving tests at speeds of 20–30 km/h, the TMEH presented steady output power up to 5.98 W, capable of driving various loads such as an electronic resistor, Li-ion battery, GNSS/INS device, driving recorder, and cellphone, either with the employment of one or two sets of harvesting coils. The approach of this study offers a promising application scenario to power up numerous electronics on a commercial transport EV platform driven by a more powerful PMSM.

Analysis of Simultaneous WPT in Ultra-Low-Power Systems with Multiple Resonating Planar Coils

This paper analyses the conceptual application of a wireless power transfer (WPT) system with multiple resonators supplying outdoor sensors using a mobile charger. The solution is based on the idea of using sensors, located in open space, to monitor environmental parameters. Instead of the typical two-coil WPT with a single charger, energy transfer is realized simultaneously, using a group of identical planar coils as transmitters and receivers connected to the independent power supply circuits of each sensor and microcontroller. By isolating these charged circuits, a higher reliability and powering flexibility of the weather station can be achieved. The concept of the proposed system was discussed, and it was proposed to include the main devices in it. A theoretical analysis was performed considering all mutual couplings and the skin effect; hence, the system is characterized by a matrix equation and sufficient formulae are given. The calculations were verified experimentally for different frequencies, two possible distances between the transmitters and receivers, and equivalent loads. Both the efficiency and load power are compared and discussed, showing that this solution can provide power to ultra-low-power devices, yet the efficiency must still be improved. At the small distance between the transmitting and receiving coils (5 mm), the maximum efficiency value was about 40%, with a load resistance of 10 Ω. By doubling the distance between the coils, the efficiency of the WPT system decreased by three times.

Method of creation of power sources for home appliances under constraints of limited resources

The subject of study in this article is the voltage ranges, methods, and tools for prototyping independent sources of power supply and artificial lighting for home appliances with reuse of only widespread components. The goal is to improve the efficiency of the creation and use of independent power supply sources for home appliances. Task: to analyze the history of the development of voltage standards for households; analyze existing autonomous power sources and types of batteries; analyze different loads; find rational voltage ranges based on fundamental values; analyze charge control and balancing circuits for lithium-based batteries; propose the technique of prototyping independent sources of power supply based on reused lithium-ion (Li-ion) accumulators; provide an example of the practical application of the results of research. According to the tasks, the following results were obtained. The evolution of voltage standards of electrical supply networks is analyzed. Types of autonomous power supplies, including pure sine versions, are discussed. The analysis of batteries for autonomous power sources of different chemical compositions is performed. It is proposed to use the water analogy of current and area as an analogy of battery capacity for visual representation of electrical processes. Models of constant current consumption and constant power consumption are considered. It is proposed to reduce the internal resistance of the battery assembly by parallel connection of the reused lithium-ion accumulators. Correspondence of voltage ranges of sequential connection of lithium-ion cells to ensure compatibility with existing devices is investigated. Rational parameters of voltage ranges to ensure compatibility of lithium-ion and acid accumulators with the ability to charge directly from solar panels without a charge controller are found. Charge controllers, battery management systems (BMS), and battery balancing circuits are analyzed. A set of steps for reuse of lithium-ion accumulators for the creation of autonomous power sources is proposed. Conclusions. The main contribution of this research is the proposed method of creation of power supply and interior lighting based on the reuse of accumulators without additional components. The discovered and proposed magic numbers of 3, 5, 7, 9, 11 and 13 for series connection of lithium-ion cells allows to obtain the equivalent of standard voltage ranges of 12 V, 19 V, 27 V, 36 V, 42 V and 48 V. The proposed technique of adjusting the voltage of the passive balancer allows adding 4.5 % to the capacity of the battery assembly. The described solutions allow to build the completely scalable autonomous low-voltage electrical supply network with the ability to charge directly from solar panels without expensive charge controllers.

A dual doping nonvolatile reconfigurable FET

In this work, we propose a dual doping based nonvolatile reconfigurable field effect transistor with source/drain (S/D) charge storage layers (DDN R-FET). It introduces nonvolatile charge storage layers on both source and drain sides as a floating program gate (FPG) instead of a program gate (PG) that needs independent power supply. The stored charges in the FPG are programmed by the control gate (CG). Therefore, the proposed DDN R-FET essentially requires only one independently powered gate to complete the reconfigurable operation. Moreover, by adjusting the charge stored in the FPGs, the CG can regulate the equivalent voltage in the FPG, which can promote the on-state current and reduce the generation of reversely biased leakage current at the same time. The physical mechanism has also been analyzed in details.

A Novel Single Gate Controlled Nonvolatile Floating Program Gate Reconfigurable FET

AbstractIn this work, a single gate controlled nonvolatile floating program gate (FPG) reconfigurable field effect transistor (RFET) is proposed. Different from the traditional RFET, it introduces a nonvolatile charge storage layer as an FPG instead of a program gate that needs independent power supply. The stored charge in the FPG can be programmed by the control gate (CG). Therefore, the proposed FPG‐RFET essentially requires only one independently powered gate to complete the reconfigurable operation. Moreover, the CG can regulate the equivalent voltage in the FPG, which can effectively reduce the static power consumption and the generation of reverse leakage current. The physical mechanism has also been analyzed in detail.

Research on Improving Methods of Power Quality of Diesel Generators with Millisecond Pulse Load

Modern radar is a typical millisecond pulse load (MPL). Still, the independent power supply system of radar with a diesel generator (DG) as the main power source will have serious frequency fluctuation and voltage distortion problems. In practical applications, the main method to solve these problems is to increase the power supply capacity. This method will cause a serious waste of resources, and the mobility of the system will deteriorate. This paper takes the diesel generator with a millisecond pulse load system (DG_MPL) as the research object. It proposes a method to improve the power quality of DG_MPL by connecting the energy storage system (ESS) on the AC side. The system uses DG as the main power source and ESS as the auxiliary power source. The equivalent frequency regulation model is studied when the inverter control mode of ESS is selected PQ, Droop, and VSG, respectively. Finally, the system operating characteristics and power quality of several common improvement methods are compared and analyzed. The results prove that the proposed method can effectively improve the system frequency and voltage distortion problems.

A novel high-low-high Schottky barrier based bidirectional tunnel field effect transistor

In this work, we proposed a novel High-Low-High Schottky barrier bidirectional tunnel field effect transistor (HLHSB-BTFET). Compared with previous technology which is named as High Schottky barrier BTFET (HSB-BTFET), the proposed HLHSB-BTFET requires only one gate electrode with independent power supply. More importantly, take an N type HLHSB-BTFET as an example, different from the previously proposed HSB-BTFET, due to that the effective potential of the central metal is increased with the increasing of drain to source voltage (Vds), built-in barrier heights maintain at the same value when the Vds is increased. Therefore, there is no strong dependence between built-in barrier heights formed in the semiconductor region on the drain side and the Vds. Besides that low Schottky barrier formed on the interface between the conduction band of silicon regions on its both sides and the central metal (while high Schottky barrier formed between the valence band of silicon regions on its both sides and the central metal) have been designed for preventing the carriers in valence band from flowing into the central metal induced by thermionic emission effect. Thereafter, the proposed N type HLHSB-BTFET has a natural blocking effect on the carriers flowing in valence band, and this blocking effect is not significantly degraded with the increasing of Vds, which is a huge promotion from the previous technology. The comparison between the two technologies is carried out, which exactly agrees with the design assumptions.

Performance evaluation of HCOOH micro-fluidic fuel cell using Ni wire electrode

A membrane-free low cost microfluidic fuel cell (μFFC) consisting a trident shaped channel is molded into a poly(dimethyl siloxane) block and Ni wires affixed therein that doubled up as the catalyst and electrical connectors. Streams of aqueous acidic solutions of formic acid as the anolyte (fuel), KMnO4 as the catholyte (oxidant) and an acid electrolyte, flown through the respective channels at a constant rate ensured laminar flow across the length of the channels, while being in contact with the Ni wires, thereby tapping its’ catalytic activity for good electrochemical performance. The effect of varying fuel or oxidant concentration on the μFFC performance is studied. In the chronopotentiometric mode, the high catalytic activity of Ni allows high currents of the order of 1.25 mA to be sustained by the cell, particularly when the surface is fresh, and this current drops when the deposition of Mn, K, and S occurs. A flow rate of 150 μL/min. is found to be optimal, as the highest open-circuit voltage (OCV) of 1.33 V is attained at this flow rate. While the cell performance is largely unaffected by formic acid concentration, but it is controlled by KMnO4 concentration. Higher oxidant concentrations yielded higher OCVs, due to more amount of the five-electron reaction, occurring at the cathode enhancing the charge separation and hence the OCV. DRT studies of the EIS data resolved two different time constants for the anodic and cathodic processes. The μFFC delivers a maximum power density of 2.1 mW/cm2 and a stable current of 3.5 mA/cm2 for more than 10 min. at 0.6 V, thus validating its deployment in a variety of applications like diagnostic devices and as an independent power supply for MEMS devices.