Electrical Accidents Research Articles

Research and analysis of electric vehicle fire accidents and review of lithium-ion battery thermal runaway mechanism

The rapid development of electric vehicles is accompanied by numerous security issue, which has caused people great concern. This paper counts the electric vehicle fire accidents in the past six years, and from three different perspectives: the time of the accident, the type of vehicle involved and the type of vehicle power to discuss these accidents. Then analyzed the various causes of electric vehicle fire accidents, such as spontaneous combustion, crash fire, etc. Explaining the three major causes of thermal runaway and the mechanism of thermal runaway in batteries. Proposing some measures and suggestions to solve the thermal runaway of electric vehicles. Through the conclusion and analysis of these accidents, this paper hopes that the new energy electric vehicles can be developed more safely and better.

Electric Scooter-Related Trauma in Korea.

BackgroundThe number of users of electric scooters, which provide swift and convenient mobility options, has increased sharply over recent years as their distribution as a shared service has expanded. Although the number of accidents and related damage has increased accordingly, limited research has analyzed data on the new types of accidents arising from electric scooters. This study aimed to analyze data on trauma characteristics due to accidents that occurred during electric scooter use.MethodsA retrospective chart review was conducted for patients who visited the regional trauma center of our institute due to electric scooter accidents from April 2018 to October 2021. Information was extracted on helmet-wearing status, sex, age, drinking status, accident timeframe, accident mechanism, electric scooter proficiency (period of use), injury severity, severe trauma, lethality, admission to the intensive care unit, surgery under general anesthesia, and the trauma region.ResultsAmong the 108 patients involved in electric scooter accidents, 92 patients were not wearing a helmet. Eighty-nine patients (85.2%) were male. The average age of the patients without a helmet was 31.3 years, while that of patients with a helmet was 34.1 years. The most frequent causes of accidents were lack of electric scooter operation experience and falling off the scooter due to obstacles (90 cases). Whether surgery was performed under general anesthesia was not associated with helmet use or non-use, although all patients who underwent facial fracture surgery were not wearing a helmet.ConclusionThe craniofacial region was most frequently affected in electric scooter accidents and wearing a helmet was the best way to prevent craniofacial trauma. Although helmet-wearing is mandatory, the majority of treated patients were not wearing a helmet at the time of injury. Thus, there is an urgent need to introduce a helmet rental system, as well as strict legal requirements, to improve this situation.

Post‐Handover Quality Management Index of Electric Housing Work

Since housing electrical work is essential in the aspect of electricity use and electrical accidents, it is necessary to properly design, construct, and manage it to avoid quality problems. However, disputes are intensifying in Korea due to numerous quality problems after the house is handed over to the owner. Although related standards have been established and some studies have been conducted, there is a lack of discussion on housing electrical work because the housing quality problem is varied. In this study, the cases of quality problems that occurred in housing electrical works were investigated, while 52 quality control indices were presented and classified according to detailed work category, object, and problematic occurrences. In addition, the number of cases of quality problems for each quality management index and the repair cost ratio were used as a scale to understand the status of quality management. Finally, 11 quality indices were suggested as candidates of important indices which needed to be controlled to focus on the housing electrical work by comparing the above 52 indices. The comparison was made on which one was best suited to the Pareto principle, a quality management strategy, among the candidates for the critical index and the indices suggested by relevant standards and previous studies. The comparison results showed that the candidates of the essential indices suggested in this study conformed to the Pareto principle, while other indices hardly conformed to it. Therefore, if the quality control strategy of choice and concentration for housing electrical works is used, focusing on these vital index candidates can effectively assist in handling the occurrence of quality problems.

Research on online monitoring and cause identification system of building electrical fire

Frequent building electrical fire accidents have brought great harm to life and property. In order to prevent the occurrence of accidents and reduce the losses to the greatest extent, it is necessary to take effective measures for building electrical fires. Based on the Internet of things (IoT) technology, a system for online monitoring and cause identification of building electrical fire is proposed in this paper. For both hardware and software, this paper introduces the overall structure, component units and system functions in detail. According to the characteristics of arc fault and fire, the complete scheme of online monitoring is given, and the system workflow is also described to realize the cause identification. Finally, the effectiveness of this system is verified by practical testing. The results show that the proposed system is helpful to solve the problems in monitoring and cause identification of building electrical fire, which can not only provide decision-making basis for firefighting, but also provide strong technical support for improving the safety of low-voltage power grid.

Residual Current Detection Prototype and Simulation Method in Low Voltage DC System

With the rapid development of dc system, the residual current in dc system has become an urgent problem to be solved. However, the type B residual current devices (RCD) for ac systems could not be directly used in dc systems. In the dc system, the voltage fluctuation generated by the rectifier and the system circulating net currents generated by the line with different positive and negative parameters would interfere with the detection of RCD. In this paper, the residual current experimental platform was built firstly. Then the residual current detection prototype was developed and its operating characteristics were tested. The impedance model of human body was built for different electric shock conditions secondly. Thirdly, the influence of system factors on circulating net currents and the detection of residual current was analyzed. Finally, the configurations of RCD in dc system were proposed finally, protecting human body from electric shock and preventing electric fire accident threats.

Exploratory Factor Analysis of Safety Culture and Safety Climate in Utility Sector Electrical Accidents of Kerala State in India

Exploratory Factor Analysis of Safety Culture and Safety Climate in Utility Sector Electrical Accidents of Kerala State in India

퍼지추론 기법을 적용한 전기설비 안전진단장치 개발

Instances of arc and sparks caused by poor insulation, gradual failure or poor contact of electrical wires within power distribution panels or between electrical equipment can lead to electrical fires. In order to prevent such electrical equipment related accidents, various sensors and measuring devices are used on site to monitor and detect anomalous incidents.<BR>This research develops an electric facility diagnostic system that determines the insulation status of power distribution panels, using sensor technology. Not only does the system generate individual warnings using the sensors installed within the diagnostic system, but the system uses the Fuzzy Inference System to calculate an Insulation Safety Index which is used to holistically determine the severity of the incident. In addition, by using wireless technology, the user is able to check on the smart phone the Fuzzy Inference Insulation Safety Index and the quantity of electricity supplied to load systems.

Understanding and Discussion on Mechanical and Electrical Equipment Accident of Fully Mechanized Mining in Coal Mine

Understanding and Discussion on Mechanical and Electrical Equipment Accident of Fully Mechanized Mining in Coal Mine

Problematical aspects of using forensic expert conclusion on results of the forensic examination of electric shock accidents

The article is devoted to topical and at the same time debatable topic of using forensic expert conclusion based on forensic examination results of electric shock accidents.&#x0D; Evaluation and verification of forensic expert conclusion, as one of the sources of evidence obtained on the basis of scientific knowledge is a prerequisite for impartiality, objectivity and comprehensiveness of the investigation in criminal proceedings and court proceedings. Conclusion assessment and verification consists of the solution of two general groups of issues: 1) compliance with procedural rules and requirements while appointment, forensic examination and conclusion submission: procedural assessment; 2) correctness, scientific validity and reliability of research and the conclusion is a meaningful assessment.&#x0D; Difficulty of correctly assessing and verifying reliability and scientific validity of forensic expert conclusion by investigative bodies or the court is due to the fact that conclusion is an expert’s deduction made on the basis of specific expertise in a particular field of science and technology. Certainly, investigator or the court does not have such knowledge. Sometimes they cannot objectively assess and verify the conclusion content for correct choice of methodology, methods used and methods of problem solving. It is emphasized that solution of such issue by investigation or the court is especially difficult in default of proven methods, or when applying new types of examinations.&#x0D; The article presents some aspects of verification of the facts established in the conclusion, their consistency with other circumstances and evidence in the case. Emphasis is placed on the fact that it is often difficult to verify the facts established in while investigation of electric shock accidents, consistency of these facts with other evidence in the case, if forensic examination establishes such facts, or when examination establishes certain crime elements.&#x0D; The ways of solving some complex aspects of the substantive assessment of forensic expert conclusion by investigation or the court are identified; it is proposed to make certain changes in procedural legislation regarding the independent review of forensic expert conclusion.

Sensorless metal object detection for wireless power transfer using machine learning

PurposeThis study aims to realize a sensorless metal object detection (MOD) using machine learning, to prevent the wireless power transfer (WPT) system from the risks of electric discharge and fire accidents caused by foreign metal objects.Design/methodology/approachThe data constructed by analyzing the input impedance using the finite element method are used in machine learning. From the loci of the input impedance of systems, the trained neural network (NN), support vector machine and naive Bayes classifier judge if a metal object exists. Then the proposed method is tested by experiments too.FindingsIn the test using simulated data, all of the three machine learning methods show high accuracy of over 80% for detecting an aluminum cylinder. And in the experimental verifications, the existence of an aluminum cylinder and empty can are successfully identified by a NN.Originality/valueThis work provides a new sensorless MOD method for WPT using three machine learning methods. And it shows that NNs obtain high accuracy than the others in both simulated and experimental verifications.

Fault Tree Analysis Study of Ship Electrical Accident

Fault Tree Analysis Study of Ship Electrical Accident

Electrochromism of Viologen/Polymer Composite: From Gel to Insulating Bulk for High-Voltage Applications.

Power equipment operates under high voltages, inducing space charge accumulation on the surface of key insulating structures, which increases the risk of discharge/breakdown and the possibility of maintenance workers experiencing electric shock accidents. Hence, a visualized non-equipment space charge detection method is of great demand in the power industry. Typical electrochromic phenomenon is based on redox of the material, triggered by a voltage smaller than 5 V with a continuous current in μA~mA level, which is not applicable to high electric fields above 106 V/m with pA~nA operation current in power equipment. Until now, no naked-eye observation technique has been realized for space charge detection to ensure the operation of power systems as well as the safety of maintenance workers. In this work, a viologen/poly(vinylidene fluoride-co-hexafluoropropylene)(P(VDF–HFP)) composite is investigated from gel to insulating bulk configurations to achieve high-voltage electrical-insulating electrochromism. The results show that viologen/P(VDF–HFP) composite bulk can withstand high electric fields at the 107 V/m level, and its electrochromism is triggered by space charges. This electrochromism phenomenon can be visually extended by increasing viologen content towards 5 wt.% and shows a positive response to voltage amplitude and application duration. As viologen/P(VDF–HFP) composite bulk exhibits a typical electrical insulating performance, it could be attached to the surface of insulating structures or clamped between metal and insulating materials as a space charge accumulation indicator in high-voltage power equipment.

Analysis of the current situation of electric shock fatal occupational accident and trial of risk assessment to electric shock occupational accidents

Analysis of the current situation of electric shock fatal occupational accident and trial of risk assessment to electric shock occupational accidents

Applications of FFTA–HFACS for Analyzing Human and Organization Factors in Electric Misoperation Accidents

Human and organizational factors (HOFs) play an important role in electric misoperation accidents (EMAs), but research into the reliability of human factors is still in its infancy in the field of EMAs, and further investment in research is urgently required. To analyze the HOFs in EMAs, a hybrid method including the Human Factors Analysis and Classification System (HFACS) and fuzzy fault tree analysis (FFTA) was applied to EMAs for the first time in the paper. HFACS is used to identify and classify the HOFs with 135 accidents, reorganized as basic events (BEs), intermediate events (IEs), and top event (TE), and develop the architecture of fault tree (FT). Fuzzy aggregation is employed to address experts’ expressions and obtain the failure probabilities of the BEs and the minimal cut sets (MCSs) of the FT. The approach generates BEs failure probabilities without reliance on quantitative historical failure statistics of EMAs via qualitative records processing. The FFTA–HFACS model is applied for quantitative analysis of the probability of failure of electrical mishaps and the interaction between accident risk factors. It can assist professionals in deciding whether and where to take preventive or corrective actions and assist in knowledgeable decision-making around the electric operation and maintenance process. Finally, applying this hybrid method to EMAs, the results show that the probability of an EMAs is 1.0410 × 10−2, which is a risk level that is likely to occur and must be controlled. Two of the most important risk factors are habitual violations and supervisory violation; a combination of risk factors of inadequate work preparation and paralysis, and irresponsibility on the part of employees are also frequent errors.

Epidemiology of Occupational Electrical Injuries.

Electrical injuries are an uncommon but very destructive type of burn, with serious complications and disabilities for the victims. This study was conducted due to the importance of understanding the epidemiology of electrical accidents in planning to prevent their occurrence. This is a retrospective cross-sectional study that was performed on patients with electrical burns referred to Shahid Motahari Educational and Medical Center from 2017 to 2018. Patients' information was entered in the researcher-made information registration form, including demographic and accident-related information. In this study, most of the accidents occurred in the workplace with high-voltage electricity. Contact with overhead cables and wires was the most common cause of injury. Excision and graft surgeries were the most common type of surgery. The variables of sex, age, length of hospital stay, and type of job had a significant relationship with the type of voltage (P < .05). The difference between the ratio of men to women and the length of hospitalization in the group of injured with high-voltage electricity was greater and most of these patients were construction workers. The variables of sex, nationality, length of hospital stay, and cause of the accident had a significant relationship with the type of job (P < .05). Construction workers are the main group at risk of electrical damage in Iran. Therefore, it is recommended to conduct more extensive studies in the field of recognizing and implementing practical methods of preventing electrical injuries, especially in high-risk work environments.

A Self‐Powered Early Warning Glove with Integrated Elastic‐Arched Triboelectric Nanogenerator and Flexible Printed Circuit for Real‐Time Safety Protection

AbstractA matched and self‐powered supply for a variety of wearable electronics remains a critical challenge. Here, a fully self‐powered early warning glove (SEWG) is developed via unique elastic‐arched triboelectric nanogenerator (EA‐TENG) and flexible printed circuit technology. The EA‐TENG generates electricity from a continuous touch lightly by hand or body, as a sustainable self‐powered source that can be utilized to complete one charging process by simply five times slapping. The SEWG has the advantage that can really deliver real‐time no‐contact electrostatic monitoring when no external power is supplied, and can effectively avoid the electric shock accident in 220/380 V electric maintenance work. Quantitative analysis of the mechanical and electronic characteristics of the SEWG demonstrated its advantages in terms of stability and reliability, with consistently well performance over more than 80,000 working cycles. It is anticipated that the special design of integrated self‐powered system could produce more implications in the field of wearable/flexible electronics and human‐machine interaction.

A Fault Diagnosis and Prognosis Method for Lithium-Ion Batteries Based on a Nonlinear Autoregressive Exogenous Neural Network and Boxplot

The frequent occurrence of electric vehicle fire accidents reveals the safety hazards of batteries. When a battery fails, its symmetry is broken, which results in a rapid degradation of its safety performance and poses a great threat to electric vehicles. Therefore, accurate battery fault diagnoses and prognoses are the key to ensuring the safe and durable operation of electric vehicles. Thus, in this paper, we propose a new fault diagnosis and prognosis method for lithium-ion batteries based on a nonlinear autoregressive exogenous (NARX) neural network and boxplot for the first time. Firstly, experiments are conducted under different temperature conditions to guarantee the diversity of the data of lithium-ion batteries and then to ensure the accuracy of the fault diagnosis and prognosis at different working temperatures. Based on the collected voltage and current data, the NARX neural network is then used to accurately predict the future battery voltage. A boxplot is then used for the battery fault diagnosis and early warning based on the predicted voltage. Finally, the experimental results (in a new dataset) and a comparative study with a back propagation (BP) neural network not only validate the high precision, all-climate applicability, strong robustness and superiority of the proposed NARX model but also verify the fault diagnosis and early warning ability of the boxplot. In summary, the proposed fault diagnosis and prognosis approach is promising in real electric vehicle applications.

Analyzing the cause of human electrical accidents using Swiss Cheese model

Purpose This study aims to explore the factors influencing electrical accidents. Here, the authors aim to understand and model the causes of electrical accidents at multiple levels. Design/methodology/approach In the study, the authors have tried to put causes of accidents in the electricity distribution segment, in the framework of the Swiss Cheese model. Delphi kind of expert survey was conducted to find the Cheese Slice (level) and the causes (holes) for electrical accidents. Inputs from a hundred experts having more than five years of experience in electrical utility companies have been used to find Cheese Slice and holes, to explain the occurrence of an electrical accident. Findings Effective training for safe work practices, safe knowledge and closer supervision would go a long way to plug the holes in the Cheese Slice in human factors. The difference in perception of managers, supervisors and workers on the importance of various causes of electrical accidents are also presented and discussed. Research limitations/implications This research is based on expert opinion and survey where respondent perception is reported. Actual accident data has not been used here. Practical implications The holes or causes of accidents at different levels (Cheese Slice) have been identified for plugging or removal for better safety. Social implications Electrical energy is widely used, and therefore, electrical safety is a social concern and also improving it is a social need. Originality/value The study contributes to electrical safety issues in the electrical utility sector.

Correlation analysis of platform intelligent electric screen doors and accidents in urban rail transit

In order to determine the main factors affecting the accident of passenger falling off the track, 223 cases of subway station passengers falling off the track in mainland China from 2000 to 2020 (up to September) were collected as the research object. Among them, 13% of the samples had platform screen doors, and 87% had no platform screen doors. Considering the limitations of the statistical sample data, in order to accurately and scientifically study and judge the effectiveness of PSD in reducing the accident of passengers falling off the track, this paper uses the knowledge of advanced mathematics and statistics, combined with the passenger volume information of the station, to analyse and verify the relationship between the existence of PSD and the occurrence of the accident. The statistical results of the case show that the installation of platform screen doors in the station can reduce the occurrence of passenger falling off the rail to a certain extent. The mathematical analysis shows that the correlation between the installation of platform screen doors in the station and the passenger falling off the rail in the operation process of Urban Rail Transit reaches 0.99, which is consistent with the statistical results of this case.

Research on liquid cooling technology in the field of electric bicycle charging

The electric vehicle industry is an industry with national characteristics advocating green environmental protection, close to China’s livelihood and highly completely independent intellectual property rights. At present, electric bicycles are gradually becoming the most popular category in the market and consumers. The rapid development of electric vehicles can significantly reduce the use of fuel vehicle exhaust emissions, so as to effectively solve the long-term fuel emissions of motor vehicles and other vehicles on the source of environmental pollution. The common cause of electric vehicle fire accidents is the heat dissipation of charger. In order to improve the heat dissipation efficiency of wireless charging, combined with the disadvantages of traditional wireless charging devices, the application of liquid cooling technology in electric vehicle charging devices is studied.