• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.7
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• pp.854-859
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• 2018

This paper describes the characteristics of a hybrid supercapacitor module for power quality stabilization. Hybrid supercapacitor is an promising energy storage device that positioned between conventional EDLC and Li-ion battery. A cylindrical 7500F hybrid supercapacitor ($60{\times}138mm$) was assembled by using the $Li_4Ti_5O_{12}$ electrode as an anode and activated carbon as a cathode. Considering the ESR and efficiency has been designed to module with 41.6F 480V design results in 180 series combination. In order to determine the characteristics of the hybrid supercapacitor module for power system, hybrid supercapacitor cells were connected in series with active balancing circuit. As a result of measuring the 50kw UPS, it was discharged at the current of 104A~143A during the discharge in the voltage range of 350V~480V, and the compensation time at discharge was measured to be about 30s. These results can be used to stabilization of power quality by applying hybrid supercapacitor module.

• Journal of Drive and Control
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• v.17 no.3
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• pp.15-25
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• 2020

The cycle time and power saving effect of a hydraulic hybrid injection molding machine using a servo motor are considered in this paper. In order to verify control characteristics, such as pressure and speed, experiments were performed with the hydraulic hybrid injection molding machine, clamping force of 110 ton. The power consumption and production cycle time of a conventional hydraulic injection molding machine were measured to compare its performances with the hydraulic hybrid injection molding machine. An injection molding machine with a clamping force of 1300 ton was used as the conventional machine, the hybrid machine was implemented by replacing its induction motors with servo motors. In the remodeled hybrid machine, experiments were performed to investigate how the displacement of the mold clamping pump affects the power consumption and production cycle time. The results showed that the production cycle time of the hybrid injection molding is similar to a conventional hydraulic injection molding machine but with a significant energy saving of about 40%.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.545-546
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• 2007

A hybrid system that uses a parallel combination of wind turbine and fuel cell is modeled. Wind energy source is characterized by its intermittent and variable nature. The output power generated by the fuel cell is stable and can be properly controlled. Therefore, fuel cell system can be added to the wind turbine system for the purpose of ensuring continuous power flow. Fuel cell helps to compensate power and regulate the frequency in power system. Simulation results show the effect of the hybrid system on power regulation. The excess power generated by the wind turbine was directed to an electrolyzer to generate hydrogen and the power deficit was compensated by the fuel cell.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.2
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• pp.269-276
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• 2023

In this research works, we propose a hybrid power generation system for drone capable of staying in the air for more than 1 hour. This power system converts the alternating current generated by the generator into direct current through a diode bridge circuit to charge the battery and uses a battery system having separated cells to obtain high controllability of the power system. The fuel efficiency and the power output for individual load were analyzed, and also the performance of a selected generator was studied in this paper. The drone which is equipped with the proposed hybrid power generation system calculated 0.82 ratio for weight vs power output, and flight time of drone showed 4,179 seconds.

• Journal of IKEEE
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• v.23 no.3
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• pp.826-831
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• 2019

The stand-alone photovoltaic power systems are widely used for lighting equipment and CCTV. In order for these devices to be competitive, the life of power storage devices such as batteries is very important. The characteristic Hybrid supercapacitor is the high power density and long life. We have proposed a stand-alone photovoltaic power system that uses hybrid supercapacitor. The charge and discharge characteristics and the internal resistance of the hybrid capacitor were measured to configure the power converter. A stable maximum output point tracking control algorithm is proposed even with the change in solar radiation. In order to verify the validity of the proposed system, a prototype was fabricated and tested using a 18W hybrid capacitor and a 10W solar cell.

• Journal of Navigation and Port Research
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• v.35 no.8
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• pp.637-641
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• 2011

Ocean structure's power system is difficult to construct a stand-alone power system. Therefore, to manage effectively power system of ocean structure, it's important to construct power system which is connected fuel-cell with hybrid power system. This paper designs power system of fuel-cell for the sea based on hydrogen generation mechanism, calculation of using electric power, etc. Designed power system is analysed & simulated using LabVIEW program. And, this paper suggests design method of power system for ocean structure based on analysed & simulated results.

• New & Renewable Energy
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• v.9 no.4
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• pp.3-12
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• 2013

This paper proposes the hybrid fuel cell system that can solve disadvantages of existing fuel cell system and ensure high reliability and high stability. The system consists of PEM fuel cell, Ni-MH battery and power management system. In this system, when the power provided from the fuel cell is higher than the load power, the extra energy may be used to charge the Ni-MH battery. When the fuel cell can not provide enough energy to the load, the shortage of energy will be supplied by the Ni-MH battery. Experimental results show that the output voltage is regulated well during load variations. Also, high system efficiency is achieved.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.361-365
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• 2005

Since the fuel cell uses the hydrogen for its fuel. it has no emission and higher efficiency than an internal combustion engine. Also fuel cell is much quieter than engine generator and generates heat much less than engine generator. So it has advantage of Army's 'si lent watch' capability and the ability to operate undetected by the enemy. The fuel cell hybrid system combines a fuel cell power system with an ESS. The ESS (e.g., batteries or ultracapacitors) reduces the fuel cell's peak power and transient response requirements. It allows the fuel cell to operate more efficiently and recovery of vehicle energy during deceleration. The battery has high energy density, so it has the advantage regarding driving distance. However, it has a disadvantage considering dynamic characteristic because of low power density. One other hand. the ultracapacitor has higher power density, so it can handle sudden change or discharge of required power. Yet. it has lower energy density. so it will be bigger and heavier than the battery when it has the same energy. This paper proposes the power management strategy for multi-power source fuel cell hybrid system. which is applied with the merits of both battery and ultra capacitor by using both of them simultaneous.

• International Journal of Automotive Technology
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• v.8 no.6
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• pp.771-780
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• 2007

In recent studies, various types of multi mode electric variable transmissions of hybrid electric vehicles have been proposed. Multi mode electric variable transmission consists of two or more different types of planetary gear hybrid powertrain system(PGHP), which can change its power flow type by means of clutches for improving transmission efficiencies. Generally, the power flows can be classified into three different types such as input split, output split and compound split. In this study, we analyzed power transmission characteristics of the possible six input split systems, and found the suitable system for single or multi mode hybrid powertrain. The input split system used in PRIUS is identified as a best system for single mode, and moreover we identified some suitable systems for dual mode.

• Journal of Power Electronics
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• v.3 no.3
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• pp.145-150
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• 2003

Reliability, availability, and cost have been the major concerns for photovoltaic hybrid systems since their beginning as primary sources for much critical applications like communication units and repeaters. This paper descnbes the performance of two hybrid systems, photovoltaic-battery, wind-turbine coupled with the public-grid (PVBWG) hybrid system and photovoltaic-battery, wind-turbine coupled With the diesel generator (PVBWD) hybrid system The systems are sized to power a typical 300W/48V de telecommunication load continuously throughout the year Such hybrid systems consist of subsystems, which in turn consist of components Failure of anyone of these components may cause failure of the entire system. The reliability and availability basics, and estimation procedure for the two proposals are introduced also in this paper. The PVBWG and PVBWD system configurations are shown with the relevant mean-time-between-faIlure (MTBF) and failure rate (${\lambda}$) of each component. The characteristics equations of the two systems are deduced as a function of operating hours and the percentage of sun and wind availabilities per day. The system probability failure as well as the reliability is estimated based on the fault tree analysis technique. The results show that, by using standard or normal components MTBF, the PVBWG is more reliable and the time of periodic maintenance period is more than one year especially in the rich sites of both sun and wind, but PVBWD competes else Also, in the first five years from the system installation, the system is quit reliable and may not require any maintenance. The results show also, as the sun and wind are available, as the system reliable and available.