• Journal of Power Electronics
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• v.19 no.1
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• pp.146-157
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• 2019

The inverter is an essential part of permanent magnet synchronous motor (PMSM) drive systems. The performance of an inverter is greatly influenced by its modulation strategy. Using a proper management of modulation strategies can guarantee high performance from a PMSM under various speed conditions. Switching between modulations is a pivotal technique that determines the performance of a PMSM. Most works on hybrid methods focus on two-level induction motors drive systems. In this paper, in order to improve the performance of PMSMs under various speed conditions, a hybrid method of a pulse width modulation (PWM) control scheme based on a neutral-point-clamped (NPC) three level topology was proposed. This hybrid PWM modulation comprised space vector PWM (SVPWM) and selective harmonic elimination PWM (SHEPWM). Under low speed conditions, the SVPWM is employed to cause the PMSM to start smoothly, and to obtain a rapid response from the control system. Under high speed conditions, the SHEPWM is employed to reduce the switching frequency and to eliminate particular current harmonics. Moreover, the harmonic characteristics of different modulations are analyzed to obtain a smooth transition between the SHEPWM and the SVPWM. Experimental and simulation results indicated the effectiveness of the proposed control method.

• Journal of the korean Society of Automotive Engineers
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• v.24 no.5
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• pp.19-28
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• 2002

• Journal of Drive and Control
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• v.7 no.2
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• pp.33-41
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• 2010

• Journal of Drive and Control
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• v.7 no.2
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• pp.19-24
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• 2010

• Journal of Drive and Control
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• v.7 no.2
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• pp.2-11
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• 2010

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.9
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• pp.967-972
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• 2015

Because of recent interests in energy conservation and prevention of environmental pollution, research related to these topics is increasing. The U.S. Navy has started to study the HED (hybrid electric drive) system in order to improve the COGAG propulsion system's fuel efficiency in AEGIS destroyers. (This ship's fuel consumption is 40% of the total fuel consumption of the U.S. Navy.) In addition, the Korean Navy is considering applications of the HED system in AEGIS destroyers. The purpose of this study is to analyze the U.S.A.'s HED system and to simulate its generating mode energy saving rate using LabVIEW. The results confirmed that the fuel savings are about 700 kg/h.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.307-311
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• 2004

In this study, a novel hybrid vehicle is proposed. The vehicle has a flywheel-engine hybrid system. Flywheels are more effective as energy charge systems than electric batteries in a respect of output power density. However, transmissions to effectively drive flywheels are very complex systems such as CVTs (Continuously Variable Transmissions). In the proposed hybrid vehicle, Constant Pressure System is employed, which is hydraulic power transmission. Using Constant Pressure Systems, hydraulic CVTs are easily realized with variable displacement pumps/motors. In this paper, firstly, the proposed flywheel hybrid vehicle making use of Constant Pressure System is described. Secondly, fuel consumption characteristics of the flywheel hybrid vehicle are experimentally examined with the stationary test facility, which employs a flywheel as a load emulating vehicle inertia. Finally, the experimental results and discussions are described. Fuel consumption of 26km/L is expected for 10 mode driving schedule with vehicle mass of 1500kg.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.11
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• pp.1407-1413
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• 2013

The swing motion drive unit of a hybrid excavator is composed of an electrical motor instead of a hydraulic motor that is used in hydraulic excavators. The method to assess and guarantee the reliability of a hybrid excavator should consider combining the mechanical and the electrical failure mode effects. In particular, the swing reduction gear set of a hybrid excavator is operated under severe outdoor conditions; therefore, an accelerated life test, which is based on field operating condition, should be conducted for the newly developed reduction gear set. In this study, various qualitative methods for reliability engineering, such as FMMA, FMECA, FTA, and QFD, were used to develop the accelerated life test method for the swing drive reduction gear set for the hybrid excavator.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.277-280
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• 2006

This paper deals with the possibility on the hybrid power system concerning wind energy at a really existing island, Sunyoo-do in the west sea near Seamangeum. In the present stage, Diesel system produces all the electrical power of the Island. However, in the new proposed system of Diesel and wind energy, an optimized guideline for drive from the economic analysis on this hybrid system is given by a mathematical and statistical modelling with a share software HOMER (hybrid optimization model for electric renewables). After a series of analysis it has been shown that the hybrid system can reduce the total expenses as well as air pollution.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2342-2345
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• 2005

Robot control system considers various requirements. Firstly, it needs adaptation for unpredictable and dynamic environment. Secondly, it needs way to make do not injurious action to human because live with a person. Thirdly, it needs processing about aim of robots. In this paper proposed that these requirements effective robot control architecture. Robot control architecture can divide Deliberative, Reactive, Hybrid. Recently, robot control architecture that come Deliberative and use hybrid architecture that apply advantage of Reactive architecture is studied much. Hybrid control purpose to combine the real-time response of Reactive with the rationality of Deliberative. Our purpose is enhancement of hybrid architecture that is studied in these days. Proposed architecture that applied human's nervous system can reduce relativity between each module of existent architecture and drive response speed guarantee and safe robot action.