• Journal of the Korean Solar Energy Society
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• v.36 no.5
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• pp.19-30
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• 2016

In this study, realize voltage regulation $220Vac{\pm}10%$ or less, frequency fluctuation $60Hz{\pm}1%$ or less over the independent operation and grid-connected operation technologies for power stabilization relates to the ESS designed and manufactured in conjunction with solar installations and solar to compensate the output reduction due to the polarization of the solar module through the polarization prevention technology for preventing the optical module efficiency is lowered, in conjunction with the BMS inverter efficiency was more than 92%, more than 90% of the charging efficiency to the target. This study was designed in conjunction with the ESS solar power plants, grid-connected operation and independent operation, Peak-Cut, it can stabilize the grid via the Peak-Shifting operation

• KIEE International Transactions on Electrophysics and Applications
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• v.4C no.3
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• pp.96-100
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• 2004

The Nd： YAG laser is commonly used throughout many fields such as accurate material processing, IC marking, semiconductor annealing, medical operation devices, etc., due to the fact that it has good thermal and mechanical properties and is easy to maintain. In materials processing, it is essential to vary the laser power density for specific materials. The laser power density can be mainly controlled by the current pulse width and pulse repetition rate. It is important to control the laser energy in those fields using a pulsed laser. In this paper we propose the constant-frequency current resonant half-bridge converter and monitoring of capacitor charging voltage. This laser power supply is designed and fabricated to have less switching loss, compact size, isolation with primary and secondary transformers, and detection of capacitor charging voltage. Also, the output stabilization characteristics of this Nd： YAG laser system are investigated. The test results are described as a function of laser output energy and flashlamp arc discharging constant. At the energy storage capacitor charges constant voltage, the laser output power is 2.3％ error range in 600[V].

• Journal of Platform Technology
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• v.12 no.2
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• pp.34-44
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• 2024

This paper proposes a dynamic clock supply control algorithm and a system load power stabilization algorithm that minimizes the power consumption of the sensing system, which accounts for the largest percentage of power consumption in mobile devices, to extend the usage time of the rechargeable battery mounted on the mobile device. The dynamic clock supply control algorithm can reduce the power consumed by the sensing system by configuring a circuit to cut off the power of the sensing system and by recognizing the state of low sensor change and adjusting the measurement cycle. The system load power stabilization algorithm is an algorithm that controls the power of the surrounding module according to the power consumption state, and when it requires a lot of power, it controls the clock supply to stabilize the operation. The experimental results confirmed that applying only the dynamic clock supply control algorithm reduces the power consumed by the sensing system by 17%, and applying only the system load power stabilization algorithm reduces power consumption by 9.3%, enabling it to operate stably in situations that require a lot of power such as image processing. When both algorithms were applied, the power consumption of the battery was reduced by 67% compared to before applying the algorithm. Through this, the reliability of the proposed method was confirmed.

• Journal of Power Electronics
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• v.17 no.2
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• pp.570-578
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• 2017

This paper proposes a method to stabilize the output voltage of the secondary side of an Inductive Power Transfer (IPT) system through tuning/detuning via a serial tuned DC Voltage-controlled Variable Capacitor (DVVC). The equivalent capacitance of the DVVC changes with the conduction period of a diode in the DVVC controlled by DC voltage. The output voltage of an IPT system can be made constant when this DVVC is used as a variable resonant capacitor combined with a PI controller generating DC control voltage according to the fluctuations of the output voltage. Since a passive diode instead of an active switch is used in the DVVC, there are no active switch driving problems such as a separate voltage source or gate drivers, which makes the DVVC especially advantageous when used at the secondary side of an IPT system. Moreover, since the equivalent capacitance of the DVVC can be controlled smoothly with a DC voltage and the passive diode generates less EMI than active switches, the DVVC has the potential to be used at much higher frequencies than traditional switch mode capacitors.

• Journal of Electrical Engineering and Technology
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• v.3 no.4
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• pp.546-551
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• 2008

In this paper, a flux-lock type superconducting fault current limiter(SFCL) integrated with a voltage-controlled voltage source inverter(VC-VSI) is proposed. The suggested equipment, which consists of a flux-lock type SFCL and a VCVSI, can perform the fault current limiting operation from the occurrence of a short-circuit. In addition, it can compensate the reactive power that the non-linear load requires and also perform the uninterruptible power supply(UPS) as well as the load voltage stabilization by controlling the amplitude and the phase of the inverter's output voltage. The specification for a test model was determined and its various functions such as the fault current limiting and the power conditioning operations were presented and analyzed via computer simulation. Through the analytical results based on the computer simulation, the validity of the analysis was confirmed and its multi-operation was discussed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.423-426
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• 2001

In this paper, an electronic step-down transformer with output voltage stabilization characteristics is presented. The proposed electronic transformer has some advantages and features as follows: 1) It has 40 % weights lighter than that of commercial magnetic transformer, 2) It has output voltage stabilization characteristic with regulated output voltage over input variations, 3) It cab be operated as circuit breaker in the case of emergency, 4) It can be operated with so called soft starting function. Moreover, the electronic transformer may have stand-by power cutoff function and act as distortion compensator. This paper show the circuit diagram and present its features through various PSPICE simulations.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.1
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• pp.17-26
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• 2010

This paper proposes the stabilization modelling method of receive sensitivity of thick film oscillation circuit for air explosion shell. The proposed method minimizes the errors of the thick film oscillator which uses air explosion shell for military and it is very similar to the simulation for maximizing the efficiency. Firstly, the proposed method gets the equation of new form through statistical analysis from the data which shows always fixed and stabilized output from the real model. Secondly, the simulation is designed which is possible to predict the output, after optimization that is a model to match the each electronic component output by the equation. In a conclusion, the usefulness, the accuracy and the precision are proved as compared with the output data of real model.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.18-27
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• 2003

The goal of the UN Framework Convention on Climate Change (UNFCCC) is to stabilize atmospheric CO2 concentration for preventing global warming in future. However, there are many unknown factors regarding stabilization of CO2 concentration. What level of concentration should be appropriate to prevent global warming？ When should we stop the increase of CO2 concentration\ulcorner What kind of countermeasures of reducing CO2 emission will be available for CO2 stabilization？(omitted)

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.7
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• pp.824-832
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• 2018

According to the government's policy to demonstrate and expand the renewable energy sources, distributed generators such as PV and WP are installed and operated in distribution systems. However, there are many issues related to power quality problems including over voltage and under voltage of customers. In order to overcome these problems, the electric power company have installed a step voltage regulator (SVR) in primary feeders interconnected with distributed generators, and also have established the technical guidelines for the distributed generators to stabilize the customer voltages in distribution systems. However, it is difficult to maintain the customer voltages within allowable limit. Therefore, this paper reviews the problems of voltage control by SVR in a distribution systems interconnected with a large amount of PV systems, and proposes characteristics of operating range and voltage control limit of the small hydropower generators. Also, with the estimation of the influence to the power system voltages from the voltage control mode of generators, this paper proposes the optimal voltage control algorithm of the small hydropower generators. By programming the proposed algorithm into control simulator of exciter, it is confirmed that the proposed algorithm can contribute the voltage stabilization in distribution systems interconnected with large scaled PV systems.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.371-372
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• 2014

This review focuses on grid-connected technology for distributed energy resources(DER). The grid-connected technology is categorized into three classifications: 1) protection function; 2) power quality improvement function; 3) grid stabilization fuction. Grid codes comparison of Japan, USA, EU and Korea is also described in the paper.