On-board Battery Research Articles

Wireless Multisensors Platform for Distributed Insect Biobot Sensing Network

Recently, the combination of electronic devices with living insects has been explored for direct manipulation of insects’ locomotion. However, the potential of such controllable insect biobots for environmental sensing, especially in outdoor applications, has not been fully studied. Vision and auditory are two primary means to remotely perceive the world. By incorporating the image and sound sensors into the beetle-carried behavior control system, we designed a fully wireless, self-powered sensing backpack with a lightweight of 523 mg. This backpack not only realizes the manipulation of beetle biobots, but also allows for real-time visual and acoustic feedback tracking. According to the test results, the backpack is able to transmit images at 1–5 frames/s and ambient sound, within a range of 160 m. The dedicated waterproof design enables the operation in the moist environment without compromising the sensing capability. In addition, for extended mission durations, solar power-harvesting circuitry was added to recharge the onboard battery. By mounting this backpack on the beetle biobots, we demonstrated our preliminary efforts toward remote locomotive control of biobots indoors and outdoors. And a sensing network was also constructed with distributed multiple beetle biobot nodes for real-time environmental sensing in the field. The successful implementation of our novel system design could provide some insights into distributed insect cyborg biobots’ future application and development outdoors.

ELECTRIC VEHICLE ONBOARD CHARGING VIA HARRIS HAWKS OPTIMIZATION-BASED FRACTIONAL-ORDER SLIDING MODE CONTROLLER

Electric vehicles (EVs) have become more popular due to their excellent efficiency and pollution-free benefits. The technology requirements for onboard chargers are increasing as the number of electric vehicles increases. This research proposes a fractional-order sliding mode controller (FOSMC) for power converters to improve the efficiency of the onboard battery charger. The Harris Hawks optimization (HHO) algorithm chooses the FOSMC parameters. Independent controllers are used in a two-stage charging scheme. The grid-side ac–dc converter helps to smooth the current and voltage in the dc bus while reducing the harmonic frequency in the grid. A dc-dc converter with a constant current–constant voltage curve regulates the charging parameters of the battery on the battery side. Experiments show that HHO-based FOSMC improves the overall dynamic response of the onboard battery charger. Moreover, the proposed method performs with a current total harmonic distortion (THD) of less than 2 %. The proposed method improves 98% efficiency than existing methods such as SSA-PID and SSA- FOAFPIDF controllers.

Modelling of Electric Bus Operation and Charging Process: Potential Contribution of Local Photovoltaic Production

The transition from diesel to electric buses allows the reduction of greenhouse gas emissions. However, the impacts of charging strategies on the quality of bus services and the utility grid must be assessed to ensure the feasibility of the energy transition in the public transportation sector. This study investigates the performances of different locations and sizes of charging infrastructures by presenting the comprehensive modelling of a bus network. It also estimates the potential benefits of a local photovoltaic (PV) production to reduce negative impacts on the utility grid. The presented approach is used for modelling one urban bus line in Compiègne, France, and simulations are performed for various case studies. The results demonstrate that the proposed method allows analysing the impact of the charging process on the quality of bus services by determining the delays of arrivals. The simulations also show the impacts of charger placement on bus on-board battery capacity, total peak power demand of battery charging, and PV self-consumption ratio. The amount of PV energy used directly to charge buses remains low, although it varies between scenarios. PV energy during winter is not sufficient to fully charge buses; however, it can be enough with additional stationary storage in the summer.

On the Transition to Green Aviation

To solve the problem of harmful emissions into the atmosphere, the principles of “green aviation” have been developed, which are based on optimizing flight schedules, changing the aircraft design, using lightweight composite materials, changing the engine operation principle and design, and the fuel used. The staff of the National Research Center Zhukovsky Institute, working jointly with other institutes, develops the principles of “green aviation”. Over the past few years, specialists of the Zhukovsky Institute have developed a number of powerful switching voltage converters as part of power plants for electric and hybrid aircrafts, in particular, for charging aircraft on-board storage batteries. Owing to the use of modern solid-state electronic components and an ergonomic design, the power plant specific capacity has been brought to a level from units to tens of kW/kg. In the field of low-temperature plasma physics, work is also underway on electrohydrodynamic flow control systems for aircraft, which is of primary importance for increasing aerodynamic and energy efficiency, thus helping solve the environmental problem of reducing harmful emissions, including carbon and nitrogen oxides, and achieve significant fuel saving.

A Three-Phase Nonisolated Pseudo-Six-Phase-Based Integrated Onboard Battery Charger for Electric Vehicles

The trending modern designs of electric vehicle (EV) motors are concerned with maximizing the machine torque density while offering a fault tolerance capability. Among different available stator winding layouts, the so-called pseudo-six-phase (P6P) winding has recently been proposed, which offers an improved torque density and fault tolerance over conventional six-phase distributed winding. An integrated onboard battery charger (IOBC) has also been proposed as a new leading technology that employs the propulsion components of the EV in the charging process to achieve the highest possible charging current with zero machine torque production. In this context, this article proposes a new P6P-based IOBC system. Two different controllers have been investigated, namely, conventional proportional–resonant (PR)-based current control and predictive current control (PCC) techniques. Under the charging mode, the control objectives aim at achieving a balanced three-phase grid current while nullifying machine torque production. To this end, the sequence stator currents are regulated to ensure a balanced <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${xy}$ </tex-math></inline-formula> current, while both the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\alpha \beta }$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${ {0}}^{ {+}}{ {0}}^{ {-}}$ </tex-math></inline-formula> current components are controlled to zero. Furthermore, a novel postfault controller using a PR-based current controller has been proposed, which ensures balanced grid line currents under one open-phase fault. A comparative experimental study has been carried out under different controllers for both vehicle-to-grid (V2G) and grid-to-vehicle (G2V) modes using a 2-hp prototype machine.

Standardization of Utility Connections in Ports: Cold ironing of ships in ports

This article is about electric shore power connections in port for vessels in regular service. The main purpose is to reduce emissions from vessels while in port, and for some vessels, to include charging onboard batteries. This article does not cover the needs of vessels under repair, laid-up vessels, and permanently moored vessels.

Universal Bridgeless Nonisolated Battery Charger With Wide-Output Voltage Range

The existing onboard battery chargers (OBCs) are incompatible to adopt for different electric vehicle (EV) powertrain configurations owing to different battery pack voltages and input power supplies. This letter proposes a new universal battery charger to charge EV batteries whose output voltage is ranging from 48 to 450 V. A dual-loop distinct current controller with a seamless transition for boost and buck operations is designed, which regulates the output voltage and maintains the unity power factor at the grid side. Furthermore, an active harmonic minimization method is incorporated with the designed controller to attenuate the prominent third-harmonic in the reference current and eradicate subharmonic oscillations. The performance of the proposed OBC is validated through the MATLAB simulations and experiments on a 1.5-kW laboratory prototype with an universal ac power supply and compared with existing OBCs.

Stochastic-Geometry-Based Analysis of Multipurpose UAVs for Package and Data Delivery

Using drones for communications and transportation is drawing great attention in many practical scenarios, such as package delivery and providing additional wireless coverage. However, the increasing demand for unmanned aerial vehicles (UAVs) from industry and academia will cause aerial traffic conflicts in the future. This, in turn, motivates the idea of this article: multipurpose UAVs, acting as aerial wireless data relays and means of aerial transportation simultaneously, to deliver packages and data at the same time. This article aims to analyze the feasibility of using drones to collect and deliver data from the Internet of Things (IoT) devices to terrestrial base stations (TBSs) while delivering packages from warehouses to residential areas. We propose an algorithm to optimize the trajectory of UAVs to maximize the size of collected/delivered data while minimizing the total round trip time subject to the limited onboard battery of UAVs. Specifically, we use tools from stochastic geometry to model the locations of the IoT clusters and the TBSs and study the system performance with respect to energy efficiency, average size of collected/delivered data, and package delivery time. Our numerical results reveal that multifunctional UAVs have great potential to enhance the efficiency of both communication and transportation networks.

Implementation of EFC Charging Station by Multiport Converter with Integration of RES

Electric vehicles (EVs) are gradually becoming an integral part of the drive to accomplish sustainable energy standards. Due to their limited onboard battery capacity, EVs’ expanding popularity creates a need for widespread charging stations. However, fast charging stations, particularly Extreme Fast Charging (EFC), may impose a hassle on the electrical system due to overload during peak hours, frequent power gaps, and voltage sag. To flatten the power supply, the photovoltaic (PV) Hybrid Energy Storage Systems (HESS) and the uncertain and variable nature of PV systems always include solar and hybrid energy storage systems (HESS) such as batteries and supercapacitors. This research suggests a multi-port DC-DC converter (MPC) with a bidirectional DC-DC converter for battery ESS-integrated PV systems. The MPC can regulate the majority of active power through PV to a battery, PV to an EV charging station, HESS to an EV charging station, and PV to AC grid. Additionally, a PI controller is used for the MPC, taking both the PV and battery voltage variations into account. Therefore, the presented configuration can achieve the key benefits of greater integration, more efficiency, and reduced cost. Simulation results show the advantages of this multiport EV charging circuit with PV-HESS and design in different modes.

Self-Propelled Pre-Biased Synchronous Charge Extraction Circuit for Triboelectric Nanogenerator

Triboelectric nanogenerators (TENGs) are suitable for harvesting ambient mechanical energy to increase the battery life of the Internet of Things (IoT) devices. Energy extraction circuits (EECs) are required as an interface between TENG and the onboard battery load to rectify and improve the energy transfer efficiency. Here, for the first time, a novel “self-propelled pre-biased synchronous charge extraction (spSCE)” EEC is presented with theoretical analysis as well as experimental results. The proposed EEC offers a universal plug-and-play solution for any TENG operating under any ambient vibration, due to its self-propelled switching feature. In addition, its inbuilt pre-biasing (precharging of TENG capacitor at the operation extremes) action enhances the net transduced energy from the mechanical source beyond the per-cycle energy limit for any non-pre-biasing EEC set by the existing synchronous charge extraction (SCE) circuit. Accounting for the energy costs of spSCE actions, our experiments validated 119.7% (resp., 163.7%) energy gain over the SCE circuit at a load of 5 V (resp., 15 V).

Operation Characteristics of Discontinuous Current Mode for a Dual-Active-Bridge AC-DC Converter with an Active Energy Buffer

This paper discusses operation characteristics of discontinuous current mode (DCM) for an ac-dc isolated converter for on-board battery chargers of electric vehicles. The converter discussed in this paper consists of a front-end diode-bridge rectifier, an active energy buffer, and a dual-active-bridge dc-dc converter. The energy buffer circuit absorbs the power pulsation form the single-phase ac line into a small-rated capacitor, and thus, makes it possible to reduce a required capacitance of the dc-link capacitor. This paper explains details of the DCM control method including a technique of the ripple cancel of the inductor current, to realize the power factor correction of the line current and the voltage control of the buffer capacitor at the same time without complex calculations. Then, a reference value of the inductor current and an operation range of the dc-output voltage are discussed. Experimental results obtained by a 220-V, 6.6-kW experimental setup demonstrate a sinusoidal-line current and a controlled buffer capacitor voltage as well as a smoothed dc-output current.

Impact of Larger Capacity of EV Batteries and Higher Output of Quick Chargers on Charging Peak Load

Large-scale introduction of electric vehicles puts an electric load to the power system. Recently, the capacities of on-board batteries and the outputs of quick chargers have been increasing. Increase in battery capacity allows EV owners to charge more freely; however, the charging may concentrate at a certain time such as on Friday afternoon before a weekend, because EVs travel relatively long distance on weekend. Therefore, we evaluate the impact on the peak load, under large capacity batteries, high power quick chargers, and simultaneous charging. Charging threshold is defined as follows: when a state of charge (SOC) of an EV falls below the charging threshold, the EV goes to a quick charging station to charge. We set up cases that the charging thresholds are raised on Friday afternoon to prepare for EV use on a weekend.

Capacity Estimation of Lithium-Ion Batteries Based on Multiple Small Voltage Sections and BP Neural Networks

Accurate capacity estimation of onboard lithium-ion batteries is crucial to the performance and safety of electric vehicles. In recent years, data-driven methods based on partial charging curve have been widely studied due to their low requirement of battery knowledge and easy implementation. However, existing data-driven methods are usually based on a fixed voltage segment or state of charge, which would be failed if the charging process does not cover the predetermined segment due to the user’s free charging behavior. This paper proposes a capacity estimation method using multiple small voltage sections and back propagation neural networks. It is intended to reduce the requirement of the length of voltage segment for estimating the complete battery capacity in an incomplete charging cycle. Firstly, the voltage segment most possibly covered is selected and divided into a number of small sections. Then, sectional capacity and skewness of the voltage curve are extracted from these small voltage sections, and severed as health factors. Secondly, the Box–Cox transformation is adopted to enhance the correlation between health factors and the capacity. Thirdly, multiple back propagation neural networks are constructed to achieve capacity estimation based on each voltage section, and their weighted average is taken as the final result. Finally, two public datasets are employed to verify the accuracy and generalization of the proposed method. Results show that the root mean square error of the fusion estimation is lower than 4.5%.

ОДНОКРАТНО ІНТЕГРУЮЧА СИСТЕМА ЕЛЕКТРОПРИВОДА ПОСТІЙНОГО СТРУМУ ДЛЯ ЗАПУСКУ ГАЗОТУРБІННОГО ДВИГУНА ВЕРТОЛЬОТА

The purpose of this work is to develop a system for starting a gas turbine engine (GTE) of a helicopter, which implements interconnected control of the parameters of the current consumed from the on-board battery and the process of setting the speed by means of a valuer, which allows to optimize the dynamic characteristics of the system and increase the time spent on the energy resource of the battery. The goal was achieved in a double-circuit single-integrating electric drive system, which is astatic in current and static in speed, which corresponds to the requirements for the launch system of the GTE helicopter. As a result of the analysis of the transient characteristics of the system by current, the conditions for the existence of aperiodic, boundary, oscillatory modes, as well as the regularities of changes in the derivative current in these modes, are obtained. The magnitude of astatism by velocity and its relationship with the pattern of change in the output voltage of the velocity setter have been established. As a result of the analysis of the patterns of change in the derivative current, its minimum values for various setting parameters of the proportional regulator of the speed circuit at the time intervals of the transient characteristic have been established. It is proposed to form a transient characteristic of the electric drive system by current in three modes. Its initial section must be formed in the boundary mode, the next -in a weakly oscillatory mode. The third section should correspond to the adjustment of the regulator to a modular optimum. For the practical implementation of the proposed principle of forming the transition characteristic of the electric drive system, it is necessary to include a proportional regulator with a relay law of changing the setting parameter in the speed circuit. An analysis of the transient characteristic for current is carried out, taking into account the discrete nature of the change in the setting of the speed circuit regulator. Its comparison withthe transitional characteristic corresponding to the optimum modulo is carried out. It is established that the transient characteristicof the electric drive system with a relay regulator of the speed circuit differs from the transition characteristic tuned to the modular optimum, the absence of overregulation and smaller differences of the derivative at the interval of its existence. Thepresence of a speed specifier that allows you to stabilize the dynamic current of the electric motor and the low drops of itsderivative during the start-up of the GTE create conditions for a longer consumption of the limited energy resource of the on-board battery of the helicopter.

Bidding and Charging Scheduling Optimization for the Urban Electric Bus Operator

With the development of electric buses (EBs) in urban areas, how to effectively utilize their charging demand flexibility and the considerable energy stored in the on-board batteries becomes an urgent issue for the electric bus operator (EBO) to consider. This paper focuses on the bidding decision in energy and reserve markets for the urban EBO owning multiple electric bus stations with energy storage systems (ESSs), and the charging scheduling of all EBs. A trip-chain based electric vehicle boundary model is proposed firstly to concisely describe the flexibility region for an EB with multiple sequential trips, which can be further aggregated via a state-based approach to adapt to large-scale problems. The uncertain boundaries are also derived taking the uncertainty of trip energy consumption into account. In order to deal with the issue that the boundary aggregation will possibly influence the feasibility of decomposing the total power to each individual EB, the stochastic bidding and EB scheduling optimization problem in a hierarchical optimization framework is proposed. Accelerated Benders decomposition is utilized to efficiently solve the problem. Case studies verify that the proposed model can dramatically reduce the computational burden, effectively consider the uncertainty and take advantage of the flexibility of both EBs and ESSs to achieve better economic performance.

Trolleybuses and trams in the urban public transport network of Russian regions: problems and prospects

This study covers the problems and prospects of integrating trolleybuses and trams into the public urban transport network of the Russian regions, to the analysis of the relevant experience of individual cities of the world. As part of the implementation of the national project "Safe High-Quality Roads", the regions are financed to modernize the rolling stock of trolleybuses and trams, expand the network of routes, and create modern infrastructure. The study identified the problems of transition to electric public transport, typical for Russian regions and individual foreign cities. In most cities of Russia, the fleet of trolleybuses and trams has drastically decreased compared to the Soviet period, tram lines often interfered with traffic due to increased urban traffic and were dismantled, the infrastructure and rolling stock are worn out and do not meet safety requirements. Abroad, city authorities face other problems: equipping trolleybuses and trams with security systems that allow them to avoid collisions with pedestrians and collisions with other city transport, equipping rolling stock with on-board batteries with recharging while driving, creating low-floor models of trams and trolleybuses. Thus, the task of switching to electric public transport is common on a global scale, but the problems that the city authorities of Russian and foreign regions need to solve differ significantly.

Forming structure and testing loading cycle of automobile power supply system

The paper considers the formation of the structure of the test cycle of the vehicle power supply system, which makes it possible to simulate typical load modes. A roundabout route has been developed, which makes it possible to carry out road tests in operating conditions as close to real ones as possible. The test cycle includes seven loading stages, different in duration and power of the consumers involved. The character of changes in the on-board network voltage, generator and battery currents has been established, a comparative assessment of which can be used to determine the current technical state of the power supply system. Further research will focus on the influence of characteristic faults on the parameters of the power supply system. Keywords: vehicle power supply system, road tests, automotive generator, battery, load cycle

Galvanically Isolated On-Board Charger Fully Integrated With 6-Phase Traction Motor Drives

The rapid spread of electric vehicles is pushing for more and more compact and reliable e-axle architectures. In this scenario, the integration of the on-board battery charger with the traction drive can be a feasible way to reduce the embedded volume and number of components. Anyway, integrated chargers often present safety issues due to the absence of an isolation stage. In this work, a solution is proposed for integrating the on-board battery charger with the traction drive of road electric vehicles equipped with a 6-phase traction motor drive. The proposed charger is deeply integrated within the e-drive powertrain, to reduce the cost and volume of the e-axle with respect to non-integrated solutions, but still providing galvanic insulation, differently from all fully integrated charger in the literature. Dedicated control strategies are developed and tested for regulating the AC grid current at unitary power factor and low THD, and to avoid torque production or rotor movement during charging independently from the rotor position. Extensive simulation results show the feasibility of the proposed solution, together with a proof-of-concept validation on a commercial traction motor.

ПОДЗАРЯДКА БЕСПИЛОТНЫХ ЛЕТАТЕЛЬНЫХ АППАРАТОВ С ВЕРТИКАЛЬНЫМ ВЗЛЕТОМ-ПОСАДКОЙ НА КОНТАКТНЫХ ПЛАТФОРМАХ С АДАПТИРУЕМОЙ ШИРИНОЙ КОНТАКТНЫХ ПОЛОС

Relevance The article describes one of the modifications of ground charging platforms for electric unmanned aerial vehicles (UAVs) with vertical takeoff and landing (VTOL). It belongs to the class of charging platforms with open pads. The previously described platforms with coplanar band parallel electrodes (CBPE) have multiple parallel strip electrodes with alternating polarity, isolated from each other by narrow dielectric separators. The corresponding on-board electrodes of the multi-rotor UAV with a symmetrical frame are proposed to be arranged at the ends of the support legs under the bearing beams of the engine-propeller groups. Thus, the contact points for the quadrocopter will be at the vertices of the square. With certain geometric relationships between the width of the ground electrodes and the interelectrode distances of the on-board electrodes for any UAV position on the platform, almost 100% different polarities of the on-board electrodes is ensured after landing, and as a consequence, the ability to bring the voltage from the ground DC source to the on-board battery charger. The advantages of such platforms are: relative simplicity of design, independence of maintenance from the accuracy of landing and the ability to charge several UAVs at the same time. However, UAVs may have various sizes and therefore various interelectrode distances, which may violate the condition of different polarities of on-board electrodes after landing. Therefore, it is important to find a solution in which reliable service of the CBPE platform for UAVs of different sizes is possible. Aim of research Finding a technical solution for adaptive band width change of a CBPE landing platform that allows charging UAVs of different sizes. Research methods Prototyping the adaptable CBPE platform and pilot study of its operation. Results The proposed modification of the platform consists in arranging the switching of bands in such a way that alternating groups of bands of one polarity are formed. Bands can be grouped into 1, 2, 3, 4, etc. Such a group works as a single band of appropriate width, which can be changed discretely. In this way, it is possible to adapt the width of the platform stripes depending on the type of vehicle coming for landing. An experimental landing platform for multicopters and a variant of implementing a commuting device for platform adaptive configuration are described.

Wireless charging system for electric vehicle

The majority of electric vehicle systems are built around a number of modules intended to guarantee the high power and stability of the car on the track. Most of these parts are connected to the charging system. Dynamic wireless power transfer can help alleviate range anxiety in electric vehicles and lower the price of on-board batteries. In this regard, pure electric vehicles have long used wireless recharging, enabling charging even while the car is moving. However, due to the complexity of this method's working methodology and the presence of numerous variables and parameters, analysis is challenging. Also, whether the vehicle is moving or not specifies a number of other factors, including the speed of the vehicle, as well as the coil receivers' sizes and characteristics. The dynamic wireless recharging system’s performance can be enhanced using the unique technique presented in this study. By providing a dynamic mathematical model that can describe and measure source-to-vehicle power transfer even while it is in motion, receiver coils have been added to the proposed system to maximize charging power. All the physical parameters of the model were presented and addressed in the suggested mathematical model. The outcomes demonstrated the viability of the suggested model. Additionally, by placing two coil receivers under the car, the simulation results were validated by experimental testing.