Light Electric Vehicle Research Articles

Light electric vehicles have come to stay (problems and regulation in Estonia and Latvia)

The aim of this article is to create a comparative map of the problems related to light electric vehicles in Estonian andLatvian traffic management and outline some of the planned innovations to their traffic laws. The research problem ofthe article is to find out the main reasons why accidents involving light electric vehicles are so often and so serious.The main methods used are comparative analysis and interpretation of statistical data. The research results concludethat drivers of light cyclists often have poor driving skills, traffic rules are broken when riding a light cyclist in pairs andthere are more drunk drivers among light cyclists compared with other groups of road users. The lack of roads for lightelectric vehicles and the poor quality of the roads used are also major problems.

Light electric vehicles: the views of users and non-users

PurposeLight electric vehicles (LEVs), such as e-bikes, e-scooters and electric two-wheelers, can potentially assist the transition to a sustainable transport system due to their low energy and spatial demands. This exploratory survey study investigated and compared the views of LEV users and interested non-users on the vehicles’ advantages in Finland, Austria, Spain and Italy among urban residents (n = 4090) to understand factors influencing their adoption. Additionally, differences between personal and shared vehicles were investigated.MethodThe survey queried respondents on the advantages of either the LEV they used most often, or the LEV they were most interested in using. Of respondents, 26% were LEV users, 37% were non-users interested in using an LEV and 37% were uninterested non-users. Factors concerning comfort, accessibility, safety, and practicality of travel were formed. The effects of respondent type (user vs. non-users), LEV type, whether the LEV was shared or personal, age, gender and country were examined with a full-factorial ANOVA for each factor and some additional variables.FindingsIn general, LEVs were regarded well for travel comfort and supporting accessibility, but less positively for safety and assisting with practical aspects of travel. LEVs were also perceived environmentally friendly. Furthermore, users perceived LEVs more positively than non-users, while age and gender only mildly influenced views. The results suggest that increased familiarity with LEVs is associated with more favourable views concerning them. Existing positive views may have led to LEV use; however, experience could have changed these views as well. LEVs are novel vehicles with recognised benefits, but low familiarity may hinder adoption. Increasing familiarity with LEVs among non-users could encourage uptake, potentially supporting modal shifts from the car to LEVs and thus assist the transition to a more sustainable transport system.

An Adaptive Delay Compensated Position Sensorless PMBLDC Motor Drive With Regenerative Braking for LEV Application

This paper deals with a new terminal voltage-based rotor position sensorless algorithm of permanent magnet brushless DC (PMBLDC) motor with adaptive phase angle compensation along with regenerative braking technique for light electric vehicle (LEV) application. Removal of Hall-Effect sensors from PMBLDC motor reduces the circuit complexity and makes the motor drive system robust and compact. Back EMF based position estimation of PMBLDC motor suffers poor accuracy at low speed. In this paper, position sensorless operation is achieved at very low speed below 100rpm. Position estimation of PMBLDC motor suffers with commutation error due to several factors like non-ideal back EMF, lowpass filter used, unbalanced DC bus voltage etc. An adaptive phase angle compensation strategy is developed to mitigate this issue, considering a generalized nonideal commutation case. This method is suitable for compensation of commutation error during variable speeds over a wide speed range, which is required for EV application. Moreover, the compensation method works with motor parameters variation as well. The proposed drive topology extends the vehicle's driving range with solar PV integration and energy regeneration algorithm. The system is simulated and experimentally validated in real case scenarios.

Bridgeless Modified High-Step-Up Gain SEPIC PFC Converter Based Charger for Light EVs Battery

This study presents a two-stage on-board charger for light electric vehicles (LEVs) with low voltage battery (24-72V). The front-end of the charger has characteristics of high voltage conversion ratio and unity power factor operation achieved by a bridgeless high gain modified SEPIC converter. The high voltage conversion ratio enables the front-end to operate over a wide range of input voltages. At the back-end of the charger, an isolated positive output Luo DC-DC converter is employed to regulate the charging profile of the LEV battery under constant current (CC) and constant voltage (CV) charging modes. The presented charger operates in discontinuous conduction mode (DCM), which has dual advantages of having inherent feature of power factor correction (PFC) at the supply end along with significantly reducing the complexity of control mechanism, thereby reducing the cost and effort of control implementation. The operational analysis and design of the presented charger in DCM are covered in detail in this study and the same are further validated by means of simulations. A 650 W test bench setup is developed to authenticate the theoretical performance by means of experimental results. The experimental performance of the front-end is finally compared with other PFC topologies to highlight the merits and demerits of the presented charger.

Power Management of Renewable-Grid Integrated Smart e-Mobility System for Light Electric Vehicles

This work proposes an architecture that integrates renewable energy sources or photovoltaic (PV) systems with the dc-link of utility and acts as primary and secondary energy sources to the electric vehicle (EV) load. The proposed architecture contains the dc-link cascaded single-stage conventional H-bridge, which superimposes a dual boost interleaved (DBI) topology with a series-series resonant (SSR) converter system. Further, the SSR side contains a wireless charging system followed by the diode bridge rectifier and a Li-ion battery as an EV load. It is challenging to integrate the above system with reduced power stages. Moreover, achieving power control in an integrated single-stage system makes it more complex. Therefore, this work includes a fundamental operation and analysis of the proposed architecture. A system-level power management scheme is also provided to control the proposed system. This power management scheme includes four basic power modes that comply with different system conditions during its operation. Furthermore, the essential of the power management scheme is to ensure that the utility should support the charging structure during excess or shortage of power flow between PV and EV load. Finally, the proposed architecture has been validated using MATLAB simulation and a 1.2kW hardware prototype.

Drive Systems for Micromobility from E-bikes to Light Electric Vehicles

Drive Systems for Micromobility from E-bikes to Light Electric Vehicles

A single‐stage bridgeless isolated positive output Cuk configuration‐based unidirectional onboard battery charger

SummaryAs power factor correction rectifiers play a key component of electric vehicle (EV) battery charger, the advancements in designing of improved power quality‐based EV charger become more significant in modern era. This article exposes a single‐stage bridgeless isolated positive output (BIPO) Cuk PFC converter with a noninverted output signal. The input diode rectifier present at the input is redeemed by the bridgeless topology that eliminates the serious power quality (PQ) issues and proffers the eminent charging solution for the light electric vehicles (LEV). Unlike the conventional Cuk converter, the noninverted outcome of the BIPO converter does not require a separate amplifier for converting negative to positive output voltage. The preferred charger utilizes a single voltage and current sensor to synchronize the battery charging control in the constant current (CC) and constant voltage (CV) phases of charging. Therefore, the converter encompasses intrinsic zero current switching (ZCS) and offers low‐cost solution to the charger with reduced control complexities. The extensive state space approach is executed to analyze the marginal stability of the presented system. Moreover, the detailed loss modeling is addressed to show the charger's efficacy curve at the standard conditions. A hardware prototype of 350 W, 60 V/4 A charger is implemented to validate its steady‐state and dynamic performance.

Multi-stage constant current–constant voltage under constant temperature (MSCC-CV-CT) charging technique for lithium-ion batteries in light weight electric vehicles (EVs)

Multi-stage constant current–constant voltage under constant temperature (MSCC-CV-CT) charging technique for lithium-ion batteries in light weight electric vehicles (EVs)

MATLAB/Simulink Modeling of Regenerative Recovery Circuit with Bidirectional DC-DC Converter for Scooter

Scooter, which is in the class of light electric vehicles, is a very common transportation vehicle, especially in big cities. Brushless direct current motor (BLDCM) is preferred in scooters. These motors are a type of electric motor used in light electric vehicles (LEV) due to their features such as high efficiency, long operating life, high speed and silence operation. Although the BLDCMs used in the propulsion system of the scooter have high efficiency, they do not have a long range due to their limited battery capacity. The biggest problem with scooters is their short range. In order to solve this negativity, manufacturers are working on different solutions. In this study, MATLAB/Simulink modelling of bidirectional DC-DC converter regenerative recovery circuit for scooter was carried out. It is aimed to increase the range with regenerative recovery. The system in the proposed study is implemented for a 300W BLDCM with a rated voltage of 24V. The effect of bidirectional DC-DC converter regenerative recovery is proven by MATLAB/Simulink results.

A Single-Stage Charger for LEV Based on Quadratic Buck-Boost AC-DC Converter Topology

A single-stage AC-DC converter, which uses a quadratic buck-boost voltage gain, for LEVs' (Light Electric Vehicles) battery charging is presented in this work. Unlike conventional BCs (Battery Chargers), which employ transformer (low or high frequency) based approaches to charge low voltages LEVs' batteries, the presented charger utilizes transformerless single-stage power architecture. In order to realize desired charging of LEVs and to maintain proper transformerless voltage gain, the presented quadratic buck-boost AC-DC converter ensures high step-down gain characteristics between AC mains and low voltage battery packs. Besides realizing desired battery charging profile, the presented single-stage BC ensures high PQ (Power Quality) indices (low input current distortions and unity power factor operation) at the supply side. Notably, the presented quadratic buck-boost AC-DC converter exhibits an intrinsic power factor correction (PFC) feature at the AC input mains under discontinuous inductor current mode (DICM) operation, thereby, incurring minimum complexities during the control implementation, which further reduces the cost of the charger. The DICM operation facilitates negligible switch turn-on and diode reverse recovery losses, and therefore, ensures an improved conversion efficiency of the BC. Even if, the presented AC-DC converter employs two switching devices, the simultaneous switching of both switches shrinks the cost and complexity of driving circuitry even further. Finally, a comprehensive operational analysis, component selection criteria, and modelling of the presented quadratic buck-boost AC-DC converter-based LEVs BC are carried out and its performance is validated through a test bench set-up in a laboratory environment. Relevant results are presented to validate the efficacy of the presented quadratic buck-boost AC-DC converter for LEVs charging applications.

Improved Power Quality Charger Based on Bridgeless Canonical Switching Cell Converter for a Light Electric Vehicle

An enhanced supply side performance based cost effective, efficient, and reliable charger for light electric vehicles (LEVs), is demonstrated in this work. On one side, the bridgeless canonical switching cell (BL-CSC) power factor corrected (PFC) converter excellently satisfies the grid side requirements; whereas, the flyback converter on another side ensures ripple (twice the line frequency ripples) free charging of the LEVs under different charging modes. Notably, the outstanding input current ripple characteristic of the BL-CSC converter reduces the switch stress and filter size. Furthermore, the discontinuous conduction mode (DCM) operation of the charger adds extra benefits such as the optimized size of magnetic components, minimum need of sensing devices, minuscule possibility of flyback transformer saturation, and zero current switching (ZCS) of all semiconductor devices. Moreover, the bridgeless configuration at supply end improves the overall device count, which further reduces the cost and corresponding losses in the charger. Performance validation of the presented charger is carried in laboratory environment through a test-bench prototype. Further, the steady-state performance analysis, behavior during various dynamics like supply voltage dynamics, and DC link voltage dynamics, are tested and relevant results are presented for performance verification. Finally, a comparative analysis of the charger with other existing topologies is carried out to justify its advantages over other chargers.

The Design, Optimization, and Experimental Study of Hub and Axial Flux BLDC Motor Under Operating Conditions For Light Electric Vehicles

The Design, Optimization, and Experimental Study of Hub and Axial Flux BLDC Motor Under Operating Conditions For Light Electric Vehicles

International experience of legal regulation of personal light electric transport

The fast rhythm of modern life puts forward new requirements for human mobility, producing the demand for new ways of moving. The use of various types of individual micromobility means solves the problem of the movement of part of the population in cities, contributes to the restoration of the environment, reduces the burden on transport infrastructure and roads, but at the same time requires policy changes both at the local and national levels, because it is often associated with high public perception of the risk of road traffic crashes and the resulting increase in injuries and deaths. The article draws attention to the prevalence of personal light electric transport (not powerful electric scooters, electric scooters, segways, unicycles, gyroboards, self-balancing unicycles, gyro scooters, electric skateboards, etc.) both in the world and in Ukraine. The problem of legal regulation has been updated and an analysis of domestic legislative initiatives to determine this type of movement has been carried out. In particular, attention is drawn to the diversity of approaches to the terminological definition and understanding of the role and place of personal light electric vehicles among road users. The most effective mechanisms for the legal regulation of micromobility means are highlighted, aimed at increasing the level of protection and safety of all road users, accepted in different states and deciding issues: classifying personal light electric vehicles as “pedestrians” or defining as a vehicle, technical requirements, permissible speed, determining the age of users, the place of use and parking areas, the availability of the necessary means of protection, the definition of liability in the event of an accident, etc. Based on the analysis of foreign experience, a conclusion was made about the possibility of using certain foreign legislative developments to form a high-quality regulatory basis for regulating the use of personal light electric vehicles in Ukraine.

SMO Based Position Sensorless BLDC Motor Drive Employing Canonical Switching Cell Converter for Light Electric Vehicle

In this paper, an adaptive sliding mode observer (ASMO) based rotor position sensorless brushless DC (BLDC) motor drive with energy regeneration for light electric vehicle (LEV) is designed. A canonical switching cell (CSC) converter is introduced for optimized MPPT performance and soft starting of the motor is assured during sensorless start-up. The CSC converter provides ripple free current in the output to the voltage source inverter (VSI) and minimizes the losses. It also acts as a fundamental building block for a DC-DC converter with the least element counts. For position sensorless commutation of BLDC motor drive, ASMO technique with self-correction ability of commutation error is used. Estimation of rotor angular position and continuous speed tracking for closed loop control are achieved using this method. This control is robust and derived from linear model of BLDC motor. Proper stability analysis of the observer is derived and ensured using pole placement method. Optimal gain scheduling technique is used in ASMO, which reduces the order of the error function making the computation easier. This model is truly adaptive to any parameter variation and load perturbation. To ensure green mobility, a pulse-width modulated regenerative braking algorithm is also integrated using the same VSI, which avoids any additional converter. Experimental results validate this method as effective for EV applications

Characterization of urban distribution networks with light electric freight vehicles

The massive incorporation of light electric freight vehicles (LEFV) in the last mile distribution has been identified as one of the alternatives that large Latin American cities shall include in their agenda for cleaner and more effective public policy in logistics operations. Thence, in this paper, arouting optimization model was used to evaluate the reduction in operational cost and GHG emissionswhen fueled cargo trucks or motorcycles are replacedbyLEFV (i.e.,e-trikes or e-bikes)in the last mile distribution in large Latin American cities. Results showed that for the case of a commercial area in Bogota, and two lines of business (i.e., parcel delivery and dry chain), the use of LEFV reduces more than 50% de operational cost and more than 95% the GHG emissions. These high reductions are due to the synergistic effect of switching from fuel to electricity and reducing the energy consumption of vehicles.

A dynamic multi-axis control allocation scheme for real-time applications

The Dynamic Weighting Control Allocator (DWCA) was introduced by Sadien et al. (Control Engineering Practice, 2019) to solve the allocation problem raised by the yaw control of an on-ground aircraft. It handles the classical tradeoff between virtual reference inputs realisation and control power minimisation. But it also offers three specific features. First, the actuators reach saturation almost simultaneously, which allows an efficient recovery in case of failure. Then, several industrial requirements are taken into account, such as implementation ease, low computational cost and compatibility with certification constraints. And finally, the actuators can be prioritised, the last ones being used sparingly (to avoid overheating, fatigue, maintenance cost…) only when the virtual reference inputs cannot be realised by the first ones only. But despite its attractiveness, the DWCA is limited to the 1-dimensional case, which means that only one degree of freedom can be controlled. This is not sufficient to deal with today's challenges in the aeronautical and automotive fields, for example, where certain control problems are inherently multi-dimensional. With the progressive advent of autonomous cars, new concepts of light hybrid or electric vehicles are, for example, emerging, where both hydraulic and electric actuators are mounted on each wheel to improve the combined management of speed and steering. In this context, this paper introduces a non-trivial generalisation of the DWCA, which retains the various characteristics and advantages of the initial version and can be used in the multi-dimensional case.

Segmented Stator Switched Reluctance Motor Drive for Light Electric Vehicle

The world market of electric light vehicles will significantly increase in the coming years. What will require the development of better high-performance drives with lowcost, and, if possible, free of permanent magnets. A segmented stator switched reluctance motor is presented to fulfill this objective because it has advantages over the conventional switched reluctance machines, such as segmented stator construction, stator shorter flux paths without flux reversal, and as a consequence, fewer iron losses. Simulations will demonstrate that the proposed segmented stator switched reluctance motor drive is suitable as a powertrain for light electric vehicles.

Simulation and Experimental Analysis of Battery Types for Light Electric Vehicle

Now-a-days it can be seen that most of people are focusing on cycling for exercising and short distance travelling due to unhygienic lifestyles and increase in environmental pollution and its harmful effect on human. Looking at such circumstances this paper is focused on to generate electrical energy produced by the person via paddling and later consume the same energy for automatic running of the cycle. The demand for Electric Bikes is growing throughout the world due its characteristics of zero emission effects and longer life cycle. An electric bicycle uses electric motors for the purpose of moving which run on different types of Batteries. These batteries undergo many charging and recharging cycles in running conditions. By use of various non-conventional energy sources various batteries worked as energy storage units can be charged which will reduce the required amount of external energy for charging the batteries which will also reduce the use of fossil fuels and also will help to reduce the environmental pollution. The theme of paper is comprised in two sections, in first part a paddling mechanism is proposed which will do the energy conversion from mechanical to electrical and in later part the stored electrical energy is converted into mechanical energy to run cycle on charged batteries. A comparative analysis is also proposed for different batteries to find out efficient types in terms of economic aspects such as cost, thermal runaway, etc. in this work an electric generation mechanism by paddling the cycle is proposed for specified amount of time and based on that the generated electricity is calculated to be stored in battery for charging. Further the simulation results using MATLAB/Simulink has been analyzed for the proposed electric bicycle with different types of batteries, to study the various characteristics of the proposed set up with variation of battery parameters and distance covered by the cycle.

ANALYSIS OF TRANSPORT EMISSIONS FROM A GLOBAL PERSPECTIVE

According to the International Energy Agency (IEA), there were 16.2 million light electric vehicles (EVs) on the world's roads by the end of 2021, more than three times as many as in 2018. Those figures will grow strongly the next few years considering that EV sales doubled in 2021 compared to 2020, reaching an all-time high of 6.6 million vehicles. To better understand this high rate of sales, it is enough to think that currently as many EVs are sold in one week as were sold in the whole of 2012.

A Single-Stage Bridgeless Isolated AC–DC Conversion System for Light Electric Vehicles Charging Application

A 1- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\phi $ </tex-math></inline-formula> single-stage ac–dc power conversion unit employing bridgeless isolated modified single-ended primary inductor converter (BLIMSEPIC) is presented in this work for the light electric vehicles (LEVs) charger applications. Unlike the existing SEPIC and Cuk high-power factor (HPF) ac–dc converters, the presented BLIMSEPIC HPF ac–dc converter incorporates continuous input and output current features while operating under discontinuous current mode (DCM) condition. Therefore, it demonstrates excellent applicability in charging applications. The DCM operation considerably simplifies overall control architecture, as the presented BLIMSPEIC ac–dc converter exhibits inherent power factor correction capability under DCM operation, and therefore, significantly reduces the cost of control implementation. Besides, the continuous input and output currents attribute lessen the filter’s size and associated losses. Furthermore, the reduced voltage stress and zero current switching of semiconductor devices, together with the front-end bridgeless structure, considerably improve the conduction and switching losses of the charger. The operation, design, control, and performance of the BLIMSEPIC HPF ac–dc converter are experimentally verified, and corresponding results are presented to justify its efficacy for LEVs charging applications.