• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.06a
• /
• pp.439-439
• /
• 2009

Nowadays, source of MEMS, USN, Hybrid parts pay attention to energy harvesting. On this paper, energy harvesting was studied using piezoelectric effect. And, piezoelectric generator was designed and fabricated. Generators were designed by FEM simulation program and generators were made by attaching cymbal type metal plates on upper and bottom sides of a disc type piezoelectric ceramic. Output AC power was rectified to DC power by full bridge circuit and converted to regular voltage power by DC-DC converter. The final output power was charged to Ni-Cd battery. Using fabricated generators, output voltages dependant on thickness of ceramic, displacement of vibration, frequency of vibration were measured.

• Proceedings of the KIEE Conference
• /
• 2006.04b
• /
• pp.341-343
• /
• 2006

In this paper an integrated model of PV-AF (Photovoltaic-Active Filter) and PV-SPE (Photovoltaic Solid Polymer Electrolyte) system using PSCAD/EMTDC were explained in detail. The main concept of PV-AF system starts from the "harmonics". In order to deliver power to utility, PV system essentially needs a converter system. Here PV-AF system adds the function of active filter to the converter system installed in PV system, which was introduced already in several papers. PV-SPE system has been studied as a replacement of existing hydrogen production technology that emits large amount of carbon dioxide into atmosphere. Until now, these two systems, PV-AF and PV-SPE, have been considered separately. However, in this paper, characteristics and advantages of combined system are discussed in detail.

• Journal of the Korean Data and Information Science Society
• /
• v.13 no.1
• /
• pp.1-16
• /
• 2002

In this paper, we suggest and implement an on-line survey and analysis system based on the database structure. We can do trends analysis in this system and reduce the number of function because we can treat basic algorithms on the database.

• Proceedings of the KIEE Conference
• /
• 1997.07f
• /
• pp.2101-2103
• /
• 1997

In this paper, micro step driving method is used for a high performance motion control and minimizing of vibration in a industrial X-Y table. By using a mathmetical analysis method of 2 phase Hybrid-type step motor, each phase current can be optimized about unit speed and torque. We can improve the electrical and mechnical driving charicteristic of machine by applying this proposed driver to the real plant using microprocessor.

• Proceedings of the KIEE Conference
• /
• 2003.10b
• /
• pp.39-41
• /
• 2003

This paper deals with the characteristics of the permanent magnet type linear synchronous motors(PMLSMs). Firstly, the structures and the characteristics of a slotted type and a slotless type PMLSM are compared. Secondly, the analyses and the design methods of each motor are presented. Finally, slotted type PMLSM and slotless type PMLSM are designed using the presented design method.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1296-1297
• /
• 2011

This paper deals with a power-hardware-in-the loop simulation (PHILS) of permanent magnet synchronous generator (PMSG) type wind power generation system (WPGS) using a real hardware which consists of a motor generator set with motor drive, real time digital simulator (RTDS), and back-to-back converter. A digital signal processor (DSP) controls the back-to-back converter connected between the back-to-back converter and the RTDS. The proposed PHILS can effectively be applied to demonstrate the operational characteristics of PMSG type WPGS under grid connection.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.822-823
• /
• 2011

The authors analyzed harmonic current based loss of a high temperature superconducting (HTS) DC model cable. The loss in HTS DC cable is generated due to the variation of magnetic field caused by harmonic current in a HVDC transmission system. The authors designed and fabricated two meters of HTS DC model cable for verification of real loss characteristic. In this paper, the loss characteristics caused by harmonic current in the HTS DC model cable are analyzed using commercial finite element method software package. The loss of the HTS DC cable is much less than the loss of the HTS AC cable but the loss should be considered to decide a proper capacity of cooling system.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.828-829
• /
• 2011

This paper performs a comparison analysis of two types of HVDC system in Jeju power system. A traditional HVDC transmission system had been composed of line commutated converter based on thyristors and the development of semiconductors enables to apply voltage source converter using IGBTs. The detailed parameters of Jeju power system were considered to make a similar condition with real system in real time digital simulator. Two types of HVDC transmission system were modeled and simulated to compare their characteristics in Jeju power system. The simulation results demonstrate that the VSC-HVDC system has more stable performance due to the fast response speed than LCC-HVDC when the transmission capacity was fluctuated.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1306-1307
• /
• 2011

Recently, the small scale photovoltaic (PV) electronic devices are drawing attention as the upcoming PV generation system. The PV system is commonly used in small scale PV applications such as LED lighting and cell phone. This paper proposes photovoltaic output sensorless (POS) maximum power point tracking (MPPT) control for a small scale charging system of PV-nickel metal hydride battery using field-programmable gate array (FPGA) controller. A converter is connected to a small scale PV cell and battery, and performs the POS MPPT at the battery terminal current instead of being at the PV cell output voltage and current. The FPGA controller and converter operate based on POS MPPT method. The experimental results show that the nickel metal hydride battery is charged by the maximum PV output power.

• Proceedings of the KIEE Conference
• /
• 2008.10b
• /
• pp.79-80
• /
• 2008

본 논문에서는 Support Vector Machines(SVM)을 이용하여 불확실한 계통의 공칭계통에 있어서 상태들의 관계를 이끌어낸다. 우선 2차 계통의 예를 통해서 서로 다른 실근을 갖는 공칭계통에 대해서만 상태들의 관계를 일반적으로 이끌어낼 수 있음을 보이고 고차계통에 대해서는 SVM을 이용하여 그 관계를 표현한다. 공칭계통의 상태들의 관계는 슬아딩모드제어기(SMC)의 구성에 사용함으로써 SMC의 강인성을 다른 제어기법에 추가시키는 것을 가능하게 하였다.