• Journal of Auto-vehicle Safety Association
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• v.10 no.1
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• pp.12-19
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• 2018

This paper deals with the broadband electromagnetic emission test of a hybrid electric vehicle. The hybrid electric vehicle's powertrain system consists of an internal combustion engine and an EV traction motor. Depending on the SOC of the traction battery, these modes change automatically in the running state. The Korea electromagnetic compatibility regulations of KMVSS and UN WP.29 stipulated the evaluation method of hybrid electric vehicles. This study analyzes and compares two test results: internal combustion and electric motor mode. Some problems of test conditions are described and an improved test method is proposed for measuring broadband emissions of a hybrid electric vehicle. As a result, we expect this paper to be used as a consideration for improvement when test specifications are revised in the future.

• Journal of Auto-vehicle Safety Association
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• v.13 no.3
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• pp.26-31
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• 2021

Although the number of domestic electric vehicle registrations exceeded 100,000 in the first half of 2020, legal and institutional concerns for maintenance and management are insufficient. In particular, the existing automobile maintenance business and qualification holders are not prohibited from performing electric vehicle maintenance without additional qualifications or training under the current laws. In this study, we review the current status of Korean laws and regulations, examine discussions abroad such as the UK, the US, and Germany, and then discuss desirable laws and institutional reform. This study proposes to temporarily reorganize the system in a way that separates the electric vehicle maintenance business and the electric vehicle maintenance qualifications from conventional vehicle.

• Journal of the Korean Society of Safety
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• v.29 no.4
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• pp.54-60
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• 2014

This paper describes electric shock accidents on a 4.16 kV class circuit breaker for power plant. Electric shock accidents mostly involve damage of human life, in comparison with electrical fire, rate of human death tend to be higher in electric shock accidents. Specially, in a high voltage facilities rate of human death comprised about 43.7% by electric shock accidents. If electric shock accidents happen in a 4.16 kV class circuit breaker for power plant, then the power plant discontinue power production. Electric shock accidents in a power plant have a great ripple effect such as an electric power shortage. In this paper, we analyzed electric shock accidents on a 4.16 kV class circuit breaker for power plant. From the analysis results, we confirmed a cause of electric shock accidents on a 4.16 kV class circuit breaker, it happened by defect of interlock equipment or occurrence of breakdown between first feeder contactor and shielding plate. In order to reduce electric shock accidents on a 4.16 kV class circuit breaker, the power plant should consider improvement of interlock equipment and insulation of feeder contactor in circuit breaker.

• Journal of the Korean Society of Safety
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• v.29 no.4
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• pp.48-53
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• 2014

This study is analyzed for electrical fire danger by electric equipments through surveys of stable owners and the field investigation at 64 stable. Also, an experiment is performed to analyze the thermal characteristics of 4 types electric wiring according to the number of operating halogen warm lamp group and automatic waterer group in Beon-young stable in the Cheongwon location. The survey is done to investigate the occurrence of electrical fire, electric equipment, causes and dangerous equipment. As a result, halogen warm lamp group and automatic waterer group are found to have dangerous loads. In the field investigation, the mode of load capacity of the halogen warm lamp group and automatic waterer group was investigated. The mode of load capacity of halogen warm lamp group (over 3 years) is found 17A and that of the auto waterer group (10 years) is 16A. In this experiment, the halogen warm lamp group aged at least 3 years showed $109^{\circ}C$ while that aged less than 1 year appeared $83^{\circ}C$, showing the max gap of $26^{\circ}C$. The automatic waterer group aged 10 years showed $90^{\circ}C$ while that aged less than 1 year appeared $68^{\circ}C$, showing the max gap of $22^{\circ}C$. These findings indicate that the mode of load capacity needs to be considered in selecting and installing wiring for the electric equipment construction of halogen warm lamp group and automatic waterer group in stable.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.287-292
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• 2005

Safety of Station electric equipment is not analysed yet. this paper try the safety first times on the basis of hazards which railway stations contain. The stations use many electric equipment such as lights, escalator and elevator for facilitating for passengers and public moving, HVAC system making good environment and so on. The electric equipments could be changed to harmful systems to passengers and publics resulting from abnormal operation condition. To ensure safeties in the station, we need to identify and analyse the hazards in the station and to provide risk mitigation methods. In this paper, we shows processes and methods to ensure the safety, how to identify and analyse the hazards. Finally, we demonstrate how to mitigate the potential risks in the stations.

• Journal of the Korea Safety Management & Science
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• v.23 no.3
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• pp.103-113
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• 2021

As the use of capacitors in electrical appliances and electrical control circuits increases, the related electrical fire is increasing. There are various parts such as resistors, coils, and capacitors that make up an electric circuit. Among them, the ignition of a capacitor with a temporary charging function is closely related to the structural characteristics of the capacitor. Capacitors can explode due to various reasons, and the high heat generated when they explode ignites the inflammable dielectric, which in turn burns the inflammable materials such as the surrounding electric wires and spreads into a fire. In this paper, the ignition mechanism is studied by conducting a reenactment experiment on the various probabilities that can be ignited in an electric capacitor, and the prevention measures to be applied to the fire prevention are presented.

• Fire Science and Engineering
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• v.25 no.3
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• pp.63-71
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• 2011

In this study, it was evaluated the fire risk of an electric heater as representative seasonal appliances. Two type of electric heaters were used in experiments. When electric heaters were operated, temperature variation was measured around the heater. Internal structure was understood by Nondestructive inspection. It was evaluated the tire risk of electric heaters, when flammable materials were positioned ear a heater. It was also estimated the probability of a tire in case of malfunction of a safety tip-over witch. When a heater was operated in a normal condition, temperature was maintained under $80^{\circ}C$ around the heater. The possibility of a fire is very high, when a heater is covered with flammable materials or malfunction of safety parts (safety tip-over switch, anti-overheating devices).

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.177-180
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• 2006

This study is to make a basic study if solid zinc (Zn) can be used for buried reference electrode, so we examined the adequacy of zinc as reference electrode by using zinc which showed regular electrode for buried period. The deference of electric potential if zinc electrode for corrosion factor such as soil resistivity or pH didn't show fixed trend and there was no clear trend on the change of measurement period. From field test, it is known that the natural electric potential difference of CSE electrode and zinc electrode is 1,100mV, but the electric potential of zinc electrode for CSE electrode in the natural soil and copying soil was 1,094~1,158mV. There was no fixed trend on the change of measurement period and electric potential difference of zinc electrode for corrosion factors such as soil resistivity or pH. Consequently, there was 40~60mV of electric potential difference in every copying soil during the experiment measurement.

• Journal of Aerospace System Engineering
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• v.16 no.3
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• pp.42-51
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• 2022

An eVTOL aircraft, which is required to operate with low pollution/low noise in urban environments, mostly use battery-powered electric propulsion systems as power sources, not traditional propulsion systems such as reciprocating or turbine engines. Accordingly, certification preparation for the electric propulsion system and securing the safety of the electric propulsion system, are important issues. In the U.S., special technical standards equivalent to FAR Part 33 were issued to certify electric engines, and in Europe, various special conditions were established to certify electric propulsion systems. Thus, in Korea, the technical standards for the electric propulsion system for eVTOL aircraft must also be prepared in line with the U.S. and Europe. In this paper, SC E-19, the technical standard of the electric/hybrid propulsion system (EHPS) in special conditions, was analyzed. Additionally, securing the safety of the electric propulsion system of the aircraft are proposed, through the collaboration of SC E-19 technical standards with the existing aircraft safety evaluation procedure ARP 4761. Finally, through a case study of the Ehang 184 electric propulsion system, it has been confirmed that the proposed safety assurance method is applicable at the aircraft level.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.9
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• pp.1335-1342
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• 2013

Subway is electrified railway system nowadays, in which liquid dielectric transformers have been widely used, though mold type transformers are replacing it. The transformers supplies large electric power and have innate hazards causing accidents under operation. A number of researcher have carried out on failures of it and have oriented to identify transformer's failure causes and how to maintain it healthy state. The transformer failures can cause serious accidents which can provoke economic loss and leads persons to kill. In this paper, we carried out a safety activity to reveal hazards and to estimate risk of subway liquid dielectric transformers using FMEA, HAZOP and What-if methods. In case of installing safety devices in oil immersed transformer, we tried to evaluate an effect on a subsystem's failure rate. We proposed how to design subsystem failure rate and safety device failure rates.