• Journal of Electrical Engineering and Technology
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• v.6 no.1
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• pp.67-75
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• 2011

The development of electric vehicle power electronics system control, composed of DC-AC inverters and DC-DC converters, attract much research interest in the modern industry. A DC-AC inverter supplies the high-power motor torques of the propulsion system and utility loads of electric vehicles, whereas a DC-DC converter supplies the conventional low-power and low-voltage loads. However, the need for high-power bidirectional DC-DC converters in future electric vehicles has led to the development of many new topologies of DC-DC converters. The nonlinear control of power converters is an active research area in the field of power electronics. This paper focuses on the use of the fuzzy sliding mode strategy as a control strategy for buck-boost DC-DC converter power supplies in electric vehicles. The proposed fuzzy controller specifies changes in control signals based on the surface and knowledge on surface changes to satisfy the sliding mode stability and attraction conditions. The performance of the proposed fuzzy sliding controller is compared to that of the classical sliding mode controller. The satisfactory simulation results show the efficiency of the proposed control law, which reduces the chattering phenomenon. Moreover, the obtained results prove the robustness of the proposed control law against variations in load resistance and input voltage in the studied converter.

• Journal of Power System Engineering
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• v.9 no.4
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• pp.24-30
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• 2005

For a reciprocating compressor of household refrigerators, a direct analogy between the pipe flow network and the electric circuit network has been utilized to set up a mathematical model for oil supply system. Individual lubrication elements of the oil supply system, such as propeller- installed oil cap, oil galleries, radial oil feeding holes, spiral oil grooves, and various sliding surfaces have been analogized by equivalent electric elements, and these have been combined together to form an electric circuit corresponding to the whole oil supply system. By solving the closed network equations of the model, oil flow rates at various lubrication elements could be obtained. Total amount of the oil flow rate drawn into the shaft has been measured and compared reasonably well with the prediction of the numerical simulation.

• JOURNAL OF ELECTRICAL WORLD
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• no.7 s.67
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• pp.6-9
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• 1982

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.45-47
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• 1993

Load Management, is originated from efficiency improvement of energy use, or energy conservaion. Traditionally, electric utilities have constructed new power plants to meet the steadily increasing electricity demand. Power development planning, however, is becoming more difficult in the countries like Korea, Japan, and the United States, and increasing concerns about global environmental problems necessitate changes from existing supply-side options based on fossil-fuel to environmentally agreeable supply strategies. This paper discusses the demand side management strategy with emphasis on the concept, implementation scheme, and current practices employed in utilities.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.390-398
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• 2008

While road traffic of sharp rise of an international oil price and capital Seoul reaches to critical point, and a use passenger drives recklessly on the subway which is a cradle of public transportation, the depths analyzes an electric power feed system regarding a ground wealth electric car line of the subway Line 2 East Section which is a long distance (Seongsu $\sim$ Gangbyeon), and future, electric power supply Feeder Distribution Center prepares to Operational Headway shortening along an ATO signal method change by feeder increase supplement, and ensure safety to an electric power supply system, and will solve inconvenience of safe operation and use passenger.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.112-115
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• 2008

Recently, In Korea Electric power Corporation guarantee free using, which separate a class of electric supply with a group of generates electricity and supply, so a market price is decided by demand and supply that take part in a tender. In this treatise predict about demand of power by abstracting a pattern cause it (temperature and economic growth). Also it proposes market price of the best electricity power generation with predicted data that is made database and is showed by Web. The proposed system is increased satisfaction of consumer through smoothness of power supply and demand that rises competitiveness through exactly estimated demand at power supply and demand and supply market will open the future. Moreover consumers can reduce expenses of basic charge. Because they beforehand predict and analyze a mount of power spending with former times so a provider concludes the lowest price and reduction effect of basic charge that needed producing of power.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.38-41
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• 2007

The increase of $CO_2$ emission by increasing of fossil fuel usage has been understood a major cause of global warming. The supply of electric energy is heavily dependent on the massive thermal power and nuclear power plant before developing the renewable energy to supply the electric energy stably at a low price. The large and sound forged components of pressure vessel, turbine and generator are widely used in power plant such as wind power, hydroelectric power generation, nuclear power and thermal power plant. This paper is discussed the trend of manufacturing technology for pressure vessel and turbine to satisfy the required condition of utility company. It is also introduced a strategy of forging industry to cope with carbon tax.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.5
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• pp.433-440
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• 2002

Simulations were carried out to investigate the characteristics of $CO_2$ emissions for an electric powered air conditioning system. The $CO_2$ emissions were evaluated for various simulation parameters such as a power source distribution rate, power plant efficiency, power supply efficiency and system performance (COP). It was found that the $CO_2$ emissions were remarkably decreased by increasing the COP of the electric powered air conditioning system with storage tank. The $CO_2$emission per unit refrigeration capacity is 0.6 kg/RTh. And also, as the COP increase by 0.1, the $CO_2$ emissions decrease by 7.2%.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.5
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• pp.498-503
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• 2010

Recently, the industrial electric customers require a digital switchgear which can improve the safety and reliability of the power supply, and the quality of electric power by on-line monitoring the electric power information based on the internet under the ubiquitous environments. Accordingly, in this paper, a industrial switch-gear prototype is designed based on the power supply method of three phase, four-line type, and then a three-phase electric management module of the digital switchgear is made for industrial electric customer system. Finally, the three-phase voltage and current measuring function of the prototype is verified from real power load test.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.252-253
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• 2005

This paper describes a improvement of power control characteristics of ship's emergency lighting power supply(SELPS), that power factor(PF) is improved and electric power is controlled extensively, and power ON-OFF is controlled and system parameter monitored in remote distance by PC serial communication.