Electric Transportation Systems Research Articles

Implementasi Model Jigsaw Pada Pembelajaran Sistem Kelistrikan Kapal

Abstract. This study aims to determine the implementation of the Jigsaw cooperative learning model on the learning outcomes of the ship's electrical system in the second semester of the Barombong Shipping Polytechnic. The jigsaw cooperative learning model is a model of student learning in small groups of 5-6 people with heterogeneous groups, cooperating positively and each member is responsible for learning a particular problem from the material provided and conveying the material to other group members. This research is a Classroom Action Research consisting of two cycles with the stages of planning, implementation, observation and reflection. The data analysis technique used is descriptive qualitative analysis technique. The subjects of this study were 16 people in class 2 B majoring in ship engineering. Data collection techniques using tests, observation, documentation, questionnaires and field notes. The results showed that based on the learning outcomes obtained in the first cycle it can be seen that the total average score of 75.62 and 75% classical completeness and the second cycle the average score of 82 and 73% classical completeness. The implementation of the jigsaw cooperative learning model can improve learning outcomes because it provides opportunities for students to think critically on a problem and find a concept directly from the results of the analysis.

Socio-Economic and Environmental Analyses of Sustainable Public Transport in the Philippines

Electric vehicles are regarded as energy transition technology towards more sustainable and environment-friendly transportation systems. Despite the benefits of reducing the dependence on fossil fuels and greenhouse gas emissions, the adoption of electric vehicles faces several obstacles ranging from financing issues, government policies, and public acceptance. This study aims to identify the economic, environmental, and social impact of the adoption of electric vehicles for public transportation. Using the Philippines as a case study, the findings highlight the economic advantage of investing in electric public transportation with high public acceptance. The results further identify significant decrease in air pollution, reduction of greenhouse gas emissions and encourage lowering the reliance on imported fossil fuels by shifting the public transport from conventional to electric transport system. This study recommends stricter implementation of government policies on modernized public transportation, stronger government support on financing mechanisms, establishment of charging stations in public and private terminals, and boosting programs for developing local-made electric vehicles. To make electric vehicle more environment-friendly, the government must accelerate the energy transition by increasing the electricity share from renewable sources and investing in more sustainable sources of energy.

Collaborative Planning for Electricity Distribution Network and Transportation System Considering Hydrogen Fuel Cell Vehicles

Under the pressure of climate change, the transportation sector is under electrification, and electric vehicles (EVs) are encouraged to reduce their reliance on fossil fuels. However, in those regions where coal is a dominating power generation fuel source, different opinions about whether EVs can help emission reduction exist. In other words, whether EVs can help emission reduction depends on the energy system configuration and the power generation mix. To achieve the overall emission reduction in both systems, a collaborative planning strategy for electricity and transportation systems is proposed. In the electricity distribution network, the renewable energy source is planned to cope with future demand growth due to the increasing use of EVs. In the transportation network, hydrogen fuel cell vehicles (FCVs) are introduced to realize the coordinated development of different types of vehicles. The location of the hydrogen refueling stations can be planned, and the penetration ratio of internal combustion vehicles, EVs, and FCVs is optimized. The proposed planning model is verified on the 46-bus electricity distribution network and the 21-bus transportation network. The mixed-integer linear programming (MILP) and subgradient methods are employed to solve the proposed optimization model. According to the simulation results, the proposed model can achieve the lowest emission since the electricity and transportation systems can cooperate well.

Coupled Charging-and-Driving Incentives Design for Electric Vehicles in Urban Networks

Electric Vehicles (EV) impact urban networks both when driving (e.g., noise and pollution reduction) and charging. For the electrical grid, the flexibility of EV charging makes it a significant actor in “Demand Response” mechanisms. Therefore, there is a need to design incentive mechanisms to foster customer engagement. A congestion game approach is adopted to evaluate the performance of such electrical transportation system with multiple classes of vehicles: EV and Gasoline Vehicles. Both temporal and energy operating costs are considered. The latter is nonseparable as it depends on the global charging need of all EV, which is scheduled in time by a centralized aggregator in function of nonflexible consumption at charging location. Thus, driving and charging decisions are coupled. An adaptation of Beckmann’s method proves the existence of a Wardrop Equilibrium (WE) in the considered nonseparable congestion game; this WE is unique when the charging unit price is an increasing function of the global charging need. A condition on the nonflexible load is given to guarantee the monotonicity of this function. This condition is tested on real consumption data in France and in Texas, USA. Optimal tolls are used to control this electrical transportation system and then computed in order to minimize an environmental cost on a simple network topology.

Optimal coordinated operation scheduling for electric vehicle aggregator and charging stations in an integrated electricity-transportation system

The interdependences between electric power systems and transportation systems are becoming increasingly tight as the market share of electric vehicles keeps booming. Therefore, improving the operation performance of power system and transportation system as an integrated system becomes a critical issue. This paper investigates the coordination between electric vehicle charging stations and electric vehicles assuming they are managed by non-cooperative stakeholders. The operation strategies of electric vehicle charging stations can be optimized by solving a mixed integer linear optimization model while an integer optimization model offers the optimal operation strategy of electric vehicles considering travel route selections. A method for coordinating electric vehicle charging stations and an electric vehicle aggregator without exchanging or sharing private information is proposed. A marginal price based co-ordination model is used for representing the gameplay between two non-cooperative stakeholders. The proposed formulation uses charging pricing policy as an effective tool to coordinate electric vehicle charging stations and electric vehicles, considering travel route selections of electric vehicles. We propose an iterative algorithm for obtaining the optimal solution of proposed marginal price based co-ordination model. A numerical case is provided to validate the merits of proposed model, as a 78.3% total cost reduction can be achieved by adopting the proposed model, comparing to three intuitive approaches.

A Taxonomy of Supervised Learning for IDSs in SCADA Environments

Supervisory Control and Data Acquisition (SCADA) systems play an important role in monitoring industrial processes such as electric power distribution, transport systems, water distribution, and wastewater collection systems. Such systems require a particular attention with regards to security aspects, as they deal with critical infrastructures that are crucial to organizations and countries. Protecting SCADA systems from intrusion is a very challenging task because they do not only inherit traditional IT security threats but they also include additional vulnerabilities related to field components (e.g., cyber-physical attacks). Many of the existing intrusion detection techniques rely on supervised learning that consists of algorithms that are first trained with reference inputs to learn specific information, and then tested on unseen inputs for classification purposes. This article surveys supervised learning from a specific security angle, namely SCADA-based intrusion detection. Based on a systematic review process, existing literature is categorized and evaluated according to SCADA-specific requirements. Additionally, this survey reports on well-known SCADA datasets and testbeds used with machine learning methods. Finally, we present key challenges and our recommendations for using specific supervised methods for SCADA systems.

Exploring the impact of economic growth, trade openness and urbanization with evidence from a large developing economy of India towards a sustainable and practical energy policy

Causal relationship among economic growth, urbanization, energy consumption, renewable energy share, trade openness and carbon emissions in the context of a large developing economy of India over the period 1990–2015 is examined in this study. The results support the existence of co-integration among the major variables. Ridge regression is done to model the impact of these variables on carbon emission. Estimated coefficients of economic growth and energy consumption are positive and significant. The major contribution to carbon emission in India comes from total energy consumption (34.12%) and economic growth (12.49%), while renewable energy consumption shows negative impact (− 29.76%). Results support feedback hypothesis among trade and carbon emission. This is revealed that the increase in GDP and trade openness facilitates adoption of renewable and energy-efficient technologies to reduce emission. In view of continued heavy dependence on indigenous fossil fuel coal as the major energy provider, concern should be adoption of ultra-low-emission technology in coal-fired power plants for immediate relief. Development of renewable energy sources coupled with switching to electric mass transport systems and large-scale adoption of energy-efficient green technologies appear as the other most practical and sustainable policy suggestions for a vast economy like India.

Identifying spatio-temporal patterns of bus bunching in urban networks

The objective of this paper is to identify hot spots of bus bunching events at the network level, both in time and space, using Automatic Vehicle Location (AVL) data from the Athens (Greece) Public Transportation System. A two-step spatio-temporal clustering analysis is employed for identifying localized hot spots in space and time and for refining detected hot spots, based on the nature of bus bunching events. First, the Spatio-Temporal Density Based Scanning Algorithm with Noise (ST-DBSCAN) is applied to distinguish bunching patterns at the network level and subsequently a k++means algorithm is employed to distinguish different types of bunching clusters. Results offer insights on specific time periods and route segments, where bus bunching events are more likely to occur and, also, on how bus bunching clusters change over time. Further, headway deviation analysis reveals the differences in the characteristics of the various bunching event types per line, showing that routes running on shared corridors experience more issues while underlying causes may vary per line. Collectively, results can help guide practice toward more flexible solutions and control strategies. Indeed, depending on the type of spatio-temporal patterns detected, appropriate improvements in service planning and real-time control strategies may be identified in order to mitigate their negative effects and improve quality of service. In light of emerging electric public transport systems, the proposed framework can be also used to determine preventive strategies and improve reliability in affected stops prior to the deployment of charging infrastructure.

A multi-criteria decision method for performance evaluation of public charging service quality

Public electric vehicle charging infrastructure provides an essential support for sustainable electric transportation systems. However, the current development model for such infrastructure tends to emphasize quantity over quality and cannot meet the charging needs of electric vehicle users. Addressing this situation requires further guidance from governments, which should be based on performance evaluation systems. This study therefore developed a multi-criteria evaluation framework to assess the performance of public charging infrastructure in terms of planning rationality, operational efficiency, service capacity, charging safety, and sustainable development. After defining individual charging station attributes through numerical data and user/expert input, a modified Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) model was used, with vague sets to standardize, weight, and process the data. The assessed stations were subsequently ranked. The model was applied to three public charging stations in Beijing, China to verify its effectiveness and robustness. The resulting rankings can facilitate regulatory assessment of these stations’ performance and guide improvements in the quality of their charging services. The results further indicated that the sustainable development value of charging facilities is often undervalued, and relevant incentive strategies should thus be implemented by policymakers.

Research on Ship Electronic Power System Fault Diagnosis Based on Expert System

Aiming at the difficulty in locating the fault point quickly and accurately after the ship electronic power system fault. In this paper, fault diagnosis expert system is used to diagnose the fault occurred to ensure stability of power supply of ship power system. The possible faults are divided into four categories on the base of analysis of ship electrical system fault characteristics. Frame structure is used to describe the connections between the various parts of the ship power system in knowledge presentation. Expert system uses production rules to describe the specific fault and combine the ideal of fuzzy inference to dealing with the uncertainty in fault diagnosis at the same time. The expert system designed in this paper can find fault points and provide solutions quickly and accurately and improves the reliability of the ship power system by test.

Пространственное взаимодействие сетей электротранспорта в городах России

The transport systems of the largest cities in Russia usually include extensive tram and trolleybus networks. There are subways in seven million-plus cities. Thus, electric transport has a very significant role in the passenger traffic of these cities. Moreover, the mentioned elements of the electric transport system can influence each other in different ways, and the level of their spatial interaction can also differ. For example, in global practice, there are cases when most types of public transport in the city (bus, trolley, tram, minibus, etc.) are feeders to subway lines, which are usually the key mode of transport within the integrated transport system of a large city (in In some cases, the role of the subway can be performed by a light rail). In addition, tram and trolleybus can be integrated in different ways. Diverse factors and processes taking place inside the city can influence the level of this integration: replacing one mode of transport with another, shortening the lines of one of the modes of transport, etc. Various options for such interaction are described by the example of three Russia’s cities: Kazan, Samara and St. Petersburg.

Proposing and Techno-Economic Study of Smart and Integrated Electric Transportation System

Proposing and Techno-Economic Study of Smart and Integrated Electric Transportation System

Guest Editorial Special Issue on High-Power Fast Chargers and Wireless Charging

Electric transportation systems have made great strides forward in terms of performance and cost-effectiveness. Electric drivetrains provide better efficiency and higher reliability due to the lower complexity and smaller part numbers compared to combustion-based drivetrains. As such, electric transportation concepts are becoming viable for all modes of transportation. This move toward transportation electrification is enabled by the drastic improvements in battery performance, making passenger vehicles with a range of over 200 mi cost-competitive with petroleum-powered vehicles. Despite the increasing number of electric vehicles (EVs) on the roads, the lack of charging infrastructure and long charging times restricts the use of these vehicles for daily commutes and short-distance trips.

Study of LoRa (Long Range) communication for monitoring of a ship electrical system

This paper presents a study of long range (LoRa) communication for monitoring of a ship electrical system. Three categories of electrical system include generator, power distribution, and navigation are monitored. A low power communication technology of LoRa is used to transmit electrical variables such as current, voltage, and power are logged and sent to the server. Experiments using LoRa SX1278 and Arduino have been inducted to validate the performance of the communication. Three spreading factors 12, 7, 6 have been tested. From experiments results, the performance of the communication has been analysed, if has been found that 97% successful data transmission was achieved with maximum distance. Furthermore, small baud rate communication was more suitable for the application.

Graphene oxide – Based supercapacitors from agricultural wastes: A step to mass production of highly efficient electrodes for electrical transportation systems

Supercapacitors and other innovative devices for electric energy generation and storage could significantly improve ecological situation in large densely populated cities. However, for this to become reality, supercapacitors should be produced en masse via a clean, green technology from the ecologically friendly material, preferably from abundant, sustainable resources, such as agricultural waste that is a by-product of other technological cycles. Many types of agricultural waste could be considered as an abundant, low-cost carbon source for large-scale fabrication of graphene-type materials. Here, we demonstrate that widely available coconut waste can be efficiently converted into reduced graphene oxide via simple catalytic oxidation using ferrocene as an efficient and low-cost catalyst. The structure and morphology of the as-prepared materials were characterized by XRD, SEM, and TEM techniques. The results confirmed the formation of high-quality reduced graphene oxide. The as-prepared graphene oxide was then analyzed as an electrode material for supercapacitor applications. We have found that the material exhibits high performance as an electric double layer capacitor (EDLC) and demonstrates excellent cyclic stability. Therefore, the reduced graphene oxide prepared via a simple, green process from this type of agricultural waste could be a good candidate of the supercapacitor electrodes.

Identification of electric traction in the urban electric transport system

The article presents the results of a systematic review of the basis of formation and implementation of electric traction in the urban electric transport system. Its complexity is determined by the fact that various technical, technological, industrial and other subsystems and complexes are included in it, whose main purpose is to satisfy the needs of the population in transportation. Determining the basis for the formation and implementation of electric traction in the system of urban electric transport is a condition for finding methods and means of improving its efficiency, including the energetic one. Based on the proposed approach, urban electric transport was interpreted as a complex production and technical system, which allowed identifying electric traction as an electrical engineering complex, and at the same time as a technological system, and as a technological process of functioning of this system. The results of the study should be interpreted from the standpoint of synergistic ideas that will contribute to the development of the general theory of electric traction in the context of modern scientific methodology.

Development of a three-level information model for processing diagnostic information for electric transport systems

The article proposes a way to improve the existing system for forecasting the technical condition of vehicles at electric transport enterprises. The authors propose a three-level architecture of the software and hardware of the information system and its implementation in Intranet and Internet technologies. The transition to a three-level system is primarily due to the desire to reduce the information system costs, which consists of the cost of equipment, software and operating expenditures. In addition, the work defines the structure of effective forecasting of the developed system operation.

Pseudocapacitive behavior of amorphous Nb 2 O 5 at low potentials

Supercapacitor has been demonstrated as one of the most attractive electrochemical energy storage devices for practical applications, especially for electric transportation systems, because of high power density, long cycle life, impressive conversion efficiency and desirable usage safety. However, energy densities of supercapacitors are typically low comparing with lithium-ion batteries, which impedes their broad applications. The development of advanced supercapacitors mainly concerns with increasing their energy densities. Being different from conventional double layer supercapacitors, pseudocapacitive materials can deliver much higher capacitances and energy densities. For example, some metal oxides can be used as electrode materials for stable charge and discharge at high rates on the basis on of reversible surface redox reactions, resulting in desired energy densities comparable to that of lithium-ion batteries. In this work, we study an amorphous α-Nb2O5, which is prepared using a facile hydrothermal method followed by a low temperature post-annealing process. The α-Nb2O5 is evaluated as a pseudocapacitive electrode material in the LiPF6-based organic electrolyte for lithium storage performance. The α-Nb2O5 demonstrates reversible Li+ intercalation/deintercalation behavior in a voltage range of 0.1–2.5 V (vs. Li/Li+), resulting in an impressive reversible lithium storage capacity higher than 250 mAh/g at 0.2 C (1 C = 400 mA/g), together with excellent cycling stability and rate capability up to 10 C for 10000 cycles. In addition, the cyclic voltammetry (CV) profiles obtained at a low scanning rate of 0.1 mV/s show unexpected square patterns in multiple cycles even at low potentials between 1.0 and 0.1 V (vs. Li/Li+), which is distinctly different from that of crystalline orthorhombic Nb2O5 electrode material. The CV analysis also indicates apparent intercalation capacity contribution of such α-Nb2O5 electrode material during lithium ion storage. All electrochemical experiments verify typical pseudocapacitive behavior for the amorphous α-Nb2O5 material in a wide voltage range of 0.1–2.5 V (vs. Li/Li+). The special pseudocapacitive property at low potentials enables the α-Nb2O5 to be used as an attractive anode in a hybrid supercapacitor coupled with the active carbon (AC) material as cathode with a wide voltage window. As a result, the assembled α-Nb2O5//AC hybrid supercapacitor full cell can be charged to a high voltage up to 4.5 V. According to the calculated energy density of the supercapacitor based on E =1/2 CV 2, the high working voltage results in an impressive energy density of 178.5 Wh/kg for this hybrid supercapacitor cell on the basis of the mass of two active electrode materials. In addition, the full cell also shows outstanding high-rate performance, and our ongoing work will optimize associated structure to improve its cycling stability at harsh work conditions. This work offers a promising Nb2O5 material that is amorphous and showing pseudocapacitive behaviors for lithium ion storage at low potentials. Improved capacity and energy density have been achieved, together with desired cycling stability for prolonged cycles. Such an electrode material can be served as a feasible anode material for high-voltage and high-energy hybrid supercapacitor full cell when it is coupled with high-rate cathode materials.

Voltage Stability Analysis of General Cargo Ship Electrical System

Voltage Stability Analysis of General Cargo Ship Electrical System

Possibility of Using Petroleum Coke As Reducing Agent for V2O5 in Solid-Phase Synthesis of Li3V2(PO4)3

Nowadays, electrochemical batteries are playing an important role in the development of technology in various fields – consumer electronics, electric transport, and stationary energy storage systems. The main requirements for modern batteries are high specific energy and low cost. State of art lithium-ion batteries have the highest specific energy, but their cost is quite high, and that limits their production volume. Therefore, a relevant problem is the development of new low-cost electrode materials with a high specific energy. One of the most promising compounds for positive electrodes of lithium-ion batteries is lithium vanadium phosphate Li3V2(PO4)3. It has the same safety in operation as LiFePO4, and at the same time has a higher specific capacity of 197 mA·h/g vs. 170 mA·h/g in LiFePO4, and provides lithium-ion batteries higher average discharge voltage. The lithium-ion batteries with positive electrodes based on Li3V2(PO4)3 have an average discharge voltage of 4.1 V and with LiFePO4 have 3.3 V [1]. The main raw material for lithium-vanadium phosphate is vanadium pentoxide (V2O5). V5+ reduces to V3+ in the process of synthesis Li3V2(PO4)3. The aim of the present work was to study the possibility of using petroleum electrode coke as a reducing agent in the solid-phase synthesis of lithium vanadium phosphate Li3V2(PO4)3. The following reagents were used: Li2CO3 (>99.9%), NH4H2PO4 (>98%), V2O5 (>99%), petroleum electrode coke. The reagents were milled to a homogeneous mixture in a mortar, then pressed into pellets in a hydraulic press at a pressure of 6 tons per cm2. The synthesis was carried out at a temperature of 800 °C in a tubular furnace in an argon atmosphere for 5 hours. Electrodes of the following composition (% wt.) were made of the synthesized material: 80% Li3V2(PO4)3, 10% Super P, 10% LA-132. 1M LiPF6 in mixture of DMC:EMC:EC:PA (1:1:2:1 by vol.) was used as an electrolyte, Celgard®3501 was used as a separator, lithium metal foil (100 µm) was used as the negative electrode. On the 1st cycle, the discharge capacity of the cells was 130 mA∙h/g(Li3V2(PO4)3) for cells being cycled in the potential range of 3.0-4.2 V and 160 mA∙h/g(Li3V2(PO4)3) in the range of 3.0-4.8 V. According to obtained results, it can be concluded that petroleum electrode coke can be used as a reducing agent in the solid-phase synthesis of Li3V2(PO4)3. In order to improve the characteristics of Li - Li3V2(PO4)3 cells, it is necessary to optimize the synthesis method. This work was performed as part of a Government Order to Ufa Institute of Chemistry of the Russian Academy of Sciences by the Ministry of Science and Higher Education of the Russian Federation (Theme No. AAAA-A17-117011910031-7), Russia.