Hybrid Propulsion Research Articles

Battery Energy Storage Systems in Ships’ Hybrid/Electric Propulsion Systems

The shipping industry is going through a period of technology transition that aims to increase the use of carbon-neutral fuels. There is a significant trend of vessels being ordered with alternative fuel propulsion. Shipping’s future fuel market will be more diverse, reliant on multiple energy sources. One of very promising means to meet the decarbonisation requirements is to operate ships with sustainable electrical energy by integrating local renewables, shore connection systems and battery energy storage systems (BESS). With the increasing number of battery/hybrid propulsion vessels in operation and on order, this kind of vessel propulsion is becoming more common, especially in the segment of short range vessels. This paper presents review of recent studies of electrification or hybridisation, different aspects of using the marine BESS and classes of hybrid propulsion vessels. It also reviews several types of energy storage and battery management systems used for ships’ hybrid propulsion. The article describes different marine applications of BESS systems in relation to peak shaving, load levelling, spinning reserve and load response. The study also presents the very latest developments of hybrid/electric propulsion systems offered by leading maritime market manufacturers.

Physics-informed machine learning combining experiment and simulation for the design of neodymium-iron-boron permanent magnets with reduced critical-elements content

Rare-earth elements like neodymium, terbium and dysprosium are crucial to the performance of permanent magnets used in various green-energy technologies like hybrid or electric cars. To address the supply risk of those elements, we applied machine-learning techniques to design magnetic materials with reduced neodymium content and without terbium and dysprosium. However, the performance of the magnet intended to be used in electric motors should be preserved. We developed machine-learning methods that assist materials design by integrating physical models to bridge the gap between length scales, from atomistic to the micrometer-sized granular microstructure of neodymium-iron-boron permanent magnets. Through data assimilation, we combined data from experiments and simulations to build machine-learning models which we used to optimize the chemical composition and the microstructure of the magnet. We applied techniques that help to understand and interpret the results of machine learning predictions. The variables importance shows how the main design variables influence the magnetic properties. High-throughput measurements on compositionally graded sputtered films are a systematic way to generate data for machine data analysis. Using the machine learning models we show how high-performance, Nd-lean magnets can be realized.

Hybrid Propulsion Efficiency Increment through Exhaust Energy Recovery—Part 1: Radial Turbine Modelling and Design

The efficiency of Hybrid Electric Vehicles (HEVs) may be substantially increased if the energy of the exhaust gases, which do not complete the expansion inside the cylinder of the internal combustion engine, is efficiently recovered by means of a properly designed turbogenerator and employed for vehicle propulsion; previous studies, carried out by the same authors of this work, showed a potential hybrid vehicle fuel efficiency increment up to 15% by employing a 20 kW turbine on a 100 HP rated power thermal unit. The innovative thermal unit here proposed is composed of a supercharged engine endowed with a properly designed turbogenerator, which comprises two fundamental elements: an exhaust gas turbine expressly designed and optimized for the application, and a suitable electric generator necessary to convert the recovered energy into electric energy, which can be stored in the on-board energy storage system of the vehicle. In these two parts, the realistic efficiency of the innovative thermal unit for hybrid vehicle is evaluated and compared to a traditional turbocharged engine. In Part 1, the authors present a model for the prediction of the efficiency of a dedicated radial turbine, based on a simple but effective mean-line approach; the same paper also reports a design algorithm, which, owing to some assumptions and approximations, allows a fast determination of the proper turbine geometry for a given design operating condition. It is worth pointing out that, being optimized for quasi-steady power production, the exhaust gas turbine considered is quite different from the ones commonly employed for turbocharging application; for this reason, and in consideration of the required power size, such a turbine is not available on the market, nor has its development been previously carried out in the scientific literature. In the Part 2 paper, a radial turbine geometry is defined for the thermal unit previously calculated, employing the design algorithm described in Part 1; the realistic energetic advantage that could be achieved by the implementation of the turbogenerator on a hybrid propulsion system is evaluated through the performance prediction model under the different operating conditions of the thermal unit. As an overall result, it was estimated that, compared to a reference traditional turbocharged engine, the turbocompound system could gain vehicle efficiency improvement between 3.1% and 17.9%, depending on the output power level, while an average efficiency increment of 10.9% was determined for the whole operating range.

An Improved Energy Management Strategy of Diesel-Electric Hybrid Propulsion System Based on FNN-DP Strategy

Diesel-electric hybrid propulsion system (HPS) is widely applied for shunting locomotive due to the characteristics of flexible configuration, economic and environmental protection in the world. Energy management strategy (EMS) is an important design factor of HPS that can optimize the energy distribution of each power sources, improve system efficiency, and reduce fuel consumption. In this paper, the model of HPS for shunting locomotive and system operating profile are firstly carried out. Then the EMS consist of the conventional rule-based (RB) strategy rule, and a fuzzy neural network base on dynamic programming (FNN-DP) strategy are studied. Finally, the simulations were carried out with these EMSs in the system model at full operating conditions to derive the fuel consumption. The conclusion is that the theoretical optimal solution of DP provides reference and guidance for the fuzzy neural network strategy to improve the rules, and the fuel consumption of the FNN-DP strategy is 10.2% lower than the conventional RB strategy.

Conceptual design and optimal sizing of a small unmanned aerial vehicle with fuel cell and battery-powered hybrid propulsion system by meta-heuristic algorithms based on energy consumption

ABSTRACT In this paper, a new conceptual design methodology for a hybrid propulsion system consisting of the battery and hydrogen fuel cells is presented based on the minimum energy consumption of the UAV. In this context, an optimization problem with non-linear constraints is constituted to determine the wing loading, aspect ratio, stall velocity, endurance velocity, battery power, fuel cell power, maximum lift coefficient, and zero-lift drag coefficient of the UAV. The solution to this optimization problem, based on the UAV’s minimum energy consumption for the endurance and cruising flight modes, is implemented by meta-heuristic algorithms: particle swarm optimization, cuckoo search algorithm, artificial bee colony, and genetic algorithm. The results of these algorithms are compared in terms of energy consumption. This article contributes to the literature on sizing fuel cell-powered small UAVs based on minimum energy consumption and comparing different metaheuristics. According to the results, the lowest power consumption of the UAV is obtained by the particle swarm optimization algorithm as 2018.63 W. Additionally, the weight ratios calculated with the parameters obtained from the sizing optimization for the UAV propulsion system components and flight stages are compared with a benchmark study in the literature. Finally, the payload weight ratio is also increased by 28.5% by sizing optimization.

Influence of a Hybrid Manual–Electric Wheelchair Propulsion System on the User’s Muscular Effort

Abstract Self-propelled wheelchairs favour the rehabilitation process, forcing the user to be physically active. Unfortunately, in most cases, the manual propulsion is not adapted to the individual needs and physical capabilities of the user. This paper presents the results of operational tests of a wheelchair equipped with a hybrid propulsion system in which the muscle strength generated by the user is assisted by two independent electric motors. The research aimed to investigate the influence of the applied control algorithm and the assistance factor (W) on the value of the muscular effort (MA) while propelling the wheelchair with the use of push rims. A modified ARmedical AR-405 wheelchair equipped with two MagicPie 5 electric motors built into the wheelchair’s hubs with a power of 500 W was used in this research. The tests were carried out on a wheelchair test bench simulating the moment of resistance within the range of 8–11 Nm. Surface electromyography was employed for the measurement of MA, specifically, a four-channel Noraxon Mini DTS apparatus. The research was carried out on five patients from the group of C50 anthropometric dimensions. The effort was measured for four muscles: deltoid–anterior part, deltoid–posteriori part, and triceps brachii and extensor carpi radialis longus. The effectiveness of the hybrid propulsion system was observed based on the extensor carpi radialis longus muscle. In this case, for the standard wheelchair, the MA ranged from 93% to 123%. In contrast, for a wheelchair equipped with the hybrid propulsion system, at W = 70%, the MA was within the range of 43%–75%.

Marine vessel powertrain design optimization: Multiperiod modeling considering retrofits and alternative fuels

Over the coming decades, maritime transportation will transition from fossil hydrocarbon fuels to hydrogen, ammonia, and synthetic hydrocarbon fuels produced using renewable electricity as the primary energy source. In this context, a shipowner needs to identify a cost-efficient plan for the adoption of alternative fuels and onboard energy conversion system retrofits. This paper presents a multiperiod decision model for the selection of energy system components under increasingly stringent CO2 emissions regulations and cost forecasts over a multidecade planning horizon. The model considers the choice of newbuild architecture, timing of retrofits, component sizes, and allocation of fuels to converters with the objective of minimizing total cost of ownership (TCO). The decision problem is formulated as a discrete time multiperiod mixed-integer linear program. The application of the model is numerically illustrated for a Baltic Sea roll-on/roll-off ferry. The main findings are: (i) modifying the energy system with retrofits obtains 43% lower TCO compared to fuel switching alone; (ii) batteries contribute to 23% lower TCO; (iii) optimal component installation period can be shorter than their maximum lifetime; (iv) running an engine with hydrogen is favored over fuel cells and (v) hybrid propulsion is the key future-proofing design choice for short sea vessels.

Energy Flow and Electric Drive Mode Efficiency Evaluation of Different Generations of Hybrid Vehicles under Diversified Urban Traffic Conditions

Hybrid propulsion dedicated to light duty vehicles is seen as an evolutionary change from internal combustion engine (ICE) to electric propulsion. Widespread direct replacement of convection ICEs in the current energy system is impossible because ICEs are vehicles’ main source of mechanical energy. The hybrid powertrain uses the advantages of electric propulsion with the ability to charge the traction battery or have the internal combustion engine assist the system. The article compares different types of hybrid drives (with a small share of plug-in hybrid propulsion) under typical urban driving conditions. Nine vehicles were tested, and the tests were conducted over several months in various cities in Poland. The terms of the research conducted were not under the requirements of the driving test. However, they are authoritative when using the vehicle in real traffic conditions. Such conditions take into account many aspects that are relevant to a road test. It was found that urban conditions are a very suitable environment for hybrid propulsion systems, as they cover more than 50% of the distance in electric mode, regardless of the initial battery charge, in most cases.

Active Mitigation Strategy of Structure-Borne Vibration with Complex Frequency Spectra from Asymmetric Plate-like Mounting Systems in Next Generation Mobilities

The complicated spectrum produced by electric and hybrid car engines is particularly sensitive to the mid-frequency range. Furthermore, sensor placement in future mobility is crucial because when the positions and orientations of sensors are altered by excessive vehicle vibration, it results in the malfunctioning of autonomous driving systems. Smart structure-based active mounting approaches have been developed to reduce engine-induced vibration. These are made to continually adjust the mounts’ dynamic properties and enhance their performances in terms of noise, vibration, and harshness (NVH) under diverse operating circumstances. It can take the place of the engine support system’s current mount technique. The performance of the source part for reducing vibration when the structure is triggered by a sinusoidal and multi-frequency signal is the main subject of this study. The overall structure, which has two active mounts based on the source-paths-receiver structure, was modeled using a lumped parameter model. In the source section, sinusoidal, amplitude modulation (AM), and frequency modulation (FM) signals were used in order to assess the effectiveness of vibration reduction in the mid-frequency band. The normalized least mean-square (NLMS) technique was utilized to assess the effectiveness of an active mounting system, and a tracking signal was employed as a control signal. The algorithm was further expanded to the multi-NLMS algorithm to monitor the complex spectral signal. This demonstrates how an active mounting system can successfully reduce vibrations when the structure is activated by many mid-frequency complex signals.

Improvement and Optimization Configuration of Inland Ship Power and Propulsion System

Advances in power and propulsion and energy management improvements can significantly contribute to reducing emissions. The International Maritime Organization (IMO) Marpol regulations impose increasingly stringent restrictions on ship’s emission. According to the measured data of the target ship in typical working profiles, the power fluctuation, fuel consumption and emission data are analyzed, and the result represented that there are serious fuel consumption and pollution problems in the diesel engine power system. Based on the ship-engine propeller matching design theory, the ship-engine propeller model was built, and the new propulsion system power of the target ship was obtained by simulation. From the perspectives of power, economy and green, the performance and emission indexes of diesel engine and LNG engine are compared and analyzed, and the fuel cost advantage, green advantage and power performance disadvantage of LNG engine compared with diesel engine are determined. By comparing the topological structures of different hybrid propulsion forms, the new propulsion form of the ship is improved to be the gas-electric hybrid propulsion system based on the ESS (Energy Storage System), and the selection of the supercapacitors and lithium batteries is compared. Based on the low-pass filter strategy, the power distribution of the ultracapacitor and lithium battery is distributed. In order to determine the optimal ESS configuration, a capacity configuration model with investment cost, fuel cost and energy storage life as objective functions was established. NGSA-II algorithm was used to calculate the model and scheme selection was completed based on the scheme decision model. In this case, the optimal scheme significantly reduces pollutant emissions, it also reduces daily fuel costs by 38% and the result shows that we can complete the cost recovery in 1.28 years.

Systematic Overview of Newly Available Technologies in the Green Maritime Sector

The application of newly available technologies in the green maritime sector is difficult due to conflicting requirements and the inter-relation of different ecological, technological and economical parameters. The governments incentivize radical reductions in harmful emissions as an overall priority. If the politics do not change, the continuous implementation of stricter government regulations for reducing emissions will eventually result in the mandatory use of, what we currently consider, alternative fuels. Immediate application of radically different strategies would significantly increase the economic costs of maritime transport, thus jeopardizing its greatest benefit: the transport of massive quantities of freight at the lowest cost. Increased maritime transport costs would immediately disrupt the global economy, as seen recently during the COVID-19 pandemic. For this reason, the industry has shifted towards a gradual decrease in emissions through the implementation of “better” transitional solutions until alternative fuels eventually become low-cost fuels. Since this topic is very broad and interdisciplinary, our systematic overview gives insight into the state-of-the-art available technologies in green maritime transport with a focus on the following subjects: (i) alternative fuels; (ii) hybrid propulsion systems and hydrogen technologies; (iii) the benefits of digitalization in the maritime sector aimed at increasing vessel efficiency; (iv) hull drag reduction technologies; and (v) carbon capture technologies. This paper outlines the challenges, advantages and disadvantages of their implementation. The results of this analysis elucidate the current technologies’ readiness levels and their expected development over the coming years.

Age Estimation of a Hybrid Energy Storage System for Vehicular Start–Stop

Ultracapacitors are energy storage devices that have shown outstanding capability in a vast spectrum of applications, mainly in energy storage systems required to deliver short bursts of electrical energy. Ultracapacitors possess high power density while batteries possess high energy density. In this paper, a hybrid energy storage device comprising a lithium-ion ultracapacitor module and a lead acid battery was modeled, built, and tested for vehicular start–stop application, which requires a much larger number of engine cranking events than conventional vehicles. The combination of a lead acid battery with Li-ion ultracapacitors was chosen due to the fact that the vast majority of vehicles utilize lead acid batteries to crank the internal combustion engine. This allows retrofitting this hybrid setup in conventional vehicles along with the start–stop feature without inflicting damage to the already installed lead acid battery. The start–stop feature puts high stress on the lead acid battery, contributing to its faster aging. This feature is commonly found in hybrid vehicles to save the unnecessarily burned fuel during idling. This paper discusses aging of the lead acid battery as a result of being used in hybrid vehicles equipped with start–stop when used alone versus when used in the hybrid setup. The paper shows cranking tests performed on a number of cars to obtain voltage, current, power, and energy requirements for combustion engine cranking. Mathematical derivation, analysis, and an energy storage age estimation method are also presented. A set of cranking events followed by capacity checks performed on two automobile energy storage systems, one being a lead acid battery alone and the other being the proposed hybrid module, show the advantage of integrating the ultracapacitor module with the lead acid battery to extend its life span almost fivefold in a hybrid automobile.

Equivalent Consumption Minimization Strategy Based on Belt Drive System Characteristic Maps for P0 Hybrid Electric Vehicles

A P0 system is used in hybrid automobiles to improve engine economy and performance. An essential element of the P0 system for effectively transmitting power to the drive train is the belt drive system (BDS). The features of electric machine (EM) and internal combustion engines (ICE) are taken into account by standard energy management systems, such as the equivalent consumption minimization strategy (ECMS). In order to maximize the effectiveness of the P0 system, this work provides a novel formulation of the ECMS, which considers the power loss map of the BDS in addition to the characteristic maps of EM and ICE. A test bench is built up to characterize the BDS, and it is verified using an open-loop Hardware in the Loop (HIL) in the WLTP driving cycle. To find the most appropriate equivalence factors for the ECMS, which would ordinarily be tuned through trial and error, a genetic algorithm (GA) is used. With regard to the standard ECMS, the proposed methodology intends to reduce fuel usage and CO2 emissions. Two belts in BDS were tested in the WLTP to achieve CO2 savings of 1.1 and 0.9 [g/km], indicating the enhancement of system performance by using the BDS power loss maps in ECMS.

Розвиток технологій гібриднихсилових установок автомобілів

Innovations and trends in the field of power plants of hybrid cars were covered in the article. The essence of the car's power plant was analyzed. The special transmission of hybrid cars was described. The modes of operation of the power plant in a hybrid car were outlined. Modern technologies of power plants of cars were given. The issue of increasing the efficiency of propulsion system of cars, increasing fuel efficiency and reducing toxic gas emissions in modern automotive industry was considered. It was emphasized that the practical use of combined power plants allows to significantly reduce the cost of transporting goods and passengers by vehicle, as well as to improve energy and environmental characteristics. The main modes of operation of the power plant in a hybrid car were listed by the authors, in particular: electric mode, hybrid mode, charge mode. Trends in the development of electric cars, which use electric propulsion systems instead of internal combustion engines, have been outlined. The trend of recent years in the development of electric cars included: an increase in the range of travel, fast charging and improvement of power electronic systems. The modern development of hybrid cars was analyzed in the article, in particular: Plug-in hybrid cars, use of a 48-volt network, an improvement of control modes in hybrid cars and energy recovery systems. Special attention was paid to changes in driving modes of hybrid cars. In general, the technologies of power plants of cars are developing rapidly, are aimed at reducing fuel consumption. A combination of internal combustion and electric motors in hybrid cars makes it possible to achieve an optimal balance between fuel efficiency and environmental friendliness, and ensures convenience and performance when driving on the road.

A new validated open-source numerical tool for the evaluation of the performance of wind-assisted ship propulsion systems

Wind propulsion is envisioned as one of the solutions for the decarbonisation of maritime transport, as it offers high efficiency in terms of primary energy comsumption. Many wind propulsion systems already exist at various development stages, but the uncertainties over their performance is a strong obstacle to their adoption by ship owners. This paper presents a general method for the assessment of steady and unsteady performances of wind- propelled ships with 6 degrees of freedom, as implemented in the open-source program xWASP_CN. Inspired by system-based modelling, the method consists in the independent modelling of the forces acting on the ship, as functions of the ship’s 6 degrees of freedom and environmental conditions. An original root-finding algorithm that leverages the specifics of the physical problem to find the steady equilibrium is presented. The method works either like a Power Prediction Program (PPP) or like a Velocity Prediction Program (VPP). As a PPP, the forward speed and course are fixed while the required propulsive power, leeway angle, heel, trim and sinkage are solved. As a VPP, only the course is fixed and the attained forward speed, leeway angle, heel, trim and sinkage are solved. This makes the method suitable for both hybrid propulsion and pure wind propulsion. The force models can be semi-empirical (usually requiring very little input data), based on preliminary experimental or numerical results (such as forward resistance curves, lift/drag coefficients and frequency-domain sea-keeping coefficients), or full-fledged flow solvers (e.g. potential theory, CFD). Thus the method is suitable for all design stages as each force can be modelled with several levels of accuracy depending on the input data available. Comparisons of an intermediate-level model with experiments on a 18-ft catamaran fitted with a Flettner rotor and a water turbine show good agreement for steady-state results.

Comparison of side collision analyzes of electric vehicle and conventional vehicle chassis

Conventional vehicles use fossil fuels, which leads to the emission of CO, causing environmental harm. Due to the damage caused by this gas to the environment and human health, the interest in hybrid or electric cars that can use RES has increased. Parts like powertrains, which are found in conventional vehicles but not in electric ones, have caused design disparities in their respective chassis. This study aims to investigate the load distribution on the chassis of electric and conventional vehicles in the event of a side collision. After conducting a literature review and engineering calculations, a chassis was designed for both types of vehicles using the SOLIDWORKS program. The completed chassis was analyzed at a speed of 40 km/h, taking the average of the speed limits determined in the side impact test and polar impact test in the EXPLICIT module of the ANSYS WORK-BENCH program. Due to the load generated during the collision, a deformation of 150.72 mm occurred in the electric vehicle chassis and 403.78 mm in the conventional vehicle chassis. As a result of the deformations, stress of 1228.2 MPa occurred in the electric vehicle chassis base and 1000.2 MPa occurred in the conventional vehicle chassis base. These stresses exceeded the yield limit on the designed chassis bases, causing a permanent shape change in both vehicles, but no rupture occurred.

Синхронизация работы поршневого и электрического двигателя в авиационной гибридной силовой установке параллельной схемы

The article discusses the synchronization of the operation of a piston and electric engine in an aviation hybrid power plant in a parallel circuit. Diagrams of a parallel and series hybrid power plant based on a piston engine and an electric motor are presented. The features of the parallel circuit hybrid power plant are noted. The power and torque graphs of a piston engine, an electric motor and a hybrid propulsion system with a propeller are analyzed. Conclusions are drawn about the possibility of synchronizing different types of engines as part of a hybrid power plant, taking into account power losses

Aplikačné možnosti HCCI technológie

This text describes the current state of the art of HCCI technology, which is based on combining the characteristics of a petrol and diesel engine. HCCI engines offer higher fuel efficiency and lower nitrogen oxide emissions. However, they also have disadvantages such as limited load range, control complexity and cold weather starting problems. The next section of the text discusses hybrid propulsion, which uses a combination of an internal combustion engine and an electric motor. It describes the different types of hybrid powertrains such as soft hybrids, plug-in hybrids and full hybrids. Explains their advantages and possible applications. A solution is then proposed where the HCCI engine would serve as a generator in a series hybrid vehicle with an electric motor. Such an arrangement allows optimization of energy use and reduction of emissions. Finally, the relevance of HCCI technology for improving the efficiency of fuel engines and hybrid vehicle design is evaluated.

Residual Reinforcement Learning for Motion Control of a Bionic Exploration Robot—RoboDact

This paper aims to investigate the motion control method of a bionic underwater exploration robot (RoboDact). The robot is equipped with a double-joint tail fin and two undulating pectoral fins to obtain good mobility and stability. The hybrid propulsion mode helps perform stable and effective underwater exploration and measurement. To coordinate these two kinds of bionic propulsion fins and address the challenge of measurement noises and external disturbances during underwater exploration, a novel residual reinforcement learning method with parameter randomization (PR-RRL) is proposed. The control strategy is a weighted superposition of a feedback controller and a residual controller. The observation feedback controller based on active disturbance rejection control (ADRC) is adapted to improve stability and convergence. And the residual controller based on the soft actor-critic (SAC) algorithm is adapted to improve adaptability to uncertainties and disturbances. Moreover, the parameter randomization training strategy is proposed for adapting natural complicated scenarios by randomizing the partial dynamics of the underwater exploration robot during the training phase. Finally, the feasibility and efficacy of the presented motion control method are validated by comprehensive simulation tests and RoboDact prototype physical experiments.

Conceptual Design and Control Schedule Optimization for Parallel Hybrid Propulsion System of Regional Turboprop Aircraft

Current environmental policies for the aviation industry motivate the use of cleaner propulsion systems to reduce its CO2 and noise footprint in the coming years. In this context, hybrid propulsion systems have emerged as a potential solution as they have demonstrated a good trade-off between performance and low pollutant emissions. In the present work, the conceptual design and control schedule optimisation of a parallel hybrid propulsion system for the De Havilland Dash 8 regional turboprop aircraft is carried out. A parametric study of the turboprop engine with different degrees of hybridisation at design point and off-design performance analysis of the parallel hybrid propulsion system with different control schedules for an aircraft typical mission has been carried out. Overall aircraft performance parameters are used to evaluate hybrid propulsion systems with different degrees of hybridisation and control schedules. From the results, it was found that a control schedule with 10-15% hybridisation during the cruise phase is the most promising when considering the aircraft mission blocked fuel and fuel efficiency.