• 전기전자학회논문지
• /
• 제25권3호
• /
• pp.506-510
• /
• 2021

본 논문에서는 current detection 구조로 인하여 load regulation의 변화를 향상시킨 LDO를 제안하였다. 제안된 LDO 레귤레이터는 출력단에 제안된 current detection 회로를 추가하였다. 그로인하여 출력에 부하전류에 따른 전압 값의 regulation을 향상시켜 기존 LDO 레귤레이터보다 load Regulation의 변화량을 향상시켰다. 제안한 current detection 구조를 사용하여 부하전류의 변화에 따른 출력 변화를 약 60 % 가량 향상시킬 수 있었다. Cadence의 Virtuoso, Spectre 시뮬레이션을 사용하여 특성을 시뮬레이션 및 검증하였다.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2018년도 전력전자학술대회
• /
• pp.522-524
• /
• 2018

A New Direct AC LED Driver has been proposed for wide output power range and precise constant current regulation using an advanced auto commutation topology. The conventional shunt regulation method provides a stepped input current shape by fixed regulation references in the linear regulator of the each channel, which results in poor current regulation and high THD. The conventional method needs to assign a linear regulator in each LED channel so that the number of linear regulator increases when extending the number of channels especially at high power application. The proposed regulation method can drive multiple switches to regulate each LED channel current by a single amplifier with sinusoidal reference so that large number of LED channel can be simply extended with less BOM cost and low THD is obtained with the accurate current regulation thanks to the sinusoidal input current control in the closed loop control. To confirm the validity of the proposed circuit, theoretical analysis and experimental results from a 20-W LED driver prototype are presented.

• 전기전자학회논문지
• /
• 제27권3호
• /
• pp.308-312
• /
• 2023

게이트 전류 감지 구조는 LDO 레귤레이터가 오버슈트 또는 언더슈트 상황 발생 시 출력전압의 레귤레이션을 보다 효과적으로 제어하기 위해 제안되었다. 기존의 전형적인 LDO 레귤레이터는 부하전류가 변화할 때 레귤레이션 전압 변화가 발생한다. 하지만 게이트 전류 감지 구조를 이용하여 패스 트랜지스터에 있는 게이트 단자 전류를 공급/방전 함으로 인해 패스 트랜지스터의 동작 속도를 더욱 향상시킬 수 있다. 게이트 전류 감지 구조를 이용한 LDO 레귤레이터의 입력전압은 3.3 V ~ 4.5 V 이며 출력 전압은 3 V이고 부하 전류는 최대 250 mA의 값을 갖는다. 시뮬레이션 결과, 부하 전류가 250 mA 까지 변화할 때 약 9 mV의 전압 변화 값을 확인하였다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 학술대회 논문집 정보 및 제어부문
• /
• pp.528-529
• /
• 2008

Proposed buck converter includes load current sensing circuit to compensate load regulation. Because error amp has finite gain, there is load regulation in SMPS. In this paper we use variable current source that is added to positive input of comparator and current of current source is changed by sensed load current. The simulation result shows that proposed buck converter has improved load regulation than conventional buck convertor.

• 대한전기학회논문지
• /
• 제43권2호
• /
• pp.215-225
• /
• 1994

In this paper, a performance evaluation of different current regulators for induction motor drive systems fed by IGBT inverter is presented. The twoparts of current regulation are considered : current error compensation part, voltage modulation part. The characteristics of hysteresis, synchronous PI, decoupled PI, predictive, deadbeat and stage feedback controllers are analyzed and the steady-state performances and transient responses of current regulation are well compared through the simulation and experimental results.

• 통상정보연구
• /
• 제9권1호
• /
• pp.277-295
• /
• 2007

This paper presents the ODR phenomenon with a specific focus on regulatory problems. It argues that the current regulatory framework for online dispute resolution is, to a large extent, defective. Existing deficiencies result not only from a lack of comprehensive ODR law, but also from the weakness of the other modalities of regulation : norms and market. The current today's approach to regulating ODR has been unsuccessful, and it is time to re-examine that position. I would like to say that suggesting details of the optimal ODR regulatory framework is beyond the scope of this paper. From a broader perspective, the field of ODR seems to be not sufficiently regulated. Neither by law, nor by the restrains set by other norms or market. Given the current weakness of the modalities of regulation, online dispute resolution requires greater institutional and international support. It appears that adoption of internationally harmonized ODR law would not hamper the development of norms and market, but rather support their proper growth. As a result, the co-regulation approach recommended in this paper is different from both traditional state-oriented models of regulation and self-regulatory systems. Arguably, this co-regulation approach is the optimal model for regulation of online dispute resolution under current circumstances.

• 전기전자학회논문지
• /
• 제26권3호
• /
• pp.462-467
• /
• 2022

피드백 버퍼 구조는 오버슈트 및 언더슈트 현상 및 출력전압의 레귤레이션을 완화하기 위해 제안된다. 기존의 LDO 레귤레이터는 일정한 부하전류의 변화로 인해 발생하는 레귤레이션 전압 변화를 겪는다. 따라서 패스 트랜지스터의 게이트 단자의 전류를 충방전함으로써 패스 트랜지스터의 동작 속도가 향상된다. 피드백 버퍼 구조를 갖는 LDO 레귤레이터는 3.3~4.5V에서 동작하며 출력 전압은 3V이며, 최대 150mA의 부하 전류를 가집니다. 시뮬레이션 결과에 따라 부하전류가 150mA까지 일정하게 변화하였을 때 6.2mV의 레귤레이션 값을 확보하였다.

• Journal of Electrical Engineering and Technology
• /
• 제13권2호
• /
• pp.677-687
• /
• 2018

This paper presents a novel power decoupling control scheme with the bidirectional buck-boost converter for primary-side regulation photovoltaic (PV) micro-inverter. With the proposed power decoupling control scheme, small-capacitance film capacitors are used to overcome the life-span and reliability limitations of the large-capacitance electrolytic capacitors. Then, an improved flyback PV inverter is employed in continuous conduction mode with primary-side regulation for the PV power conditioning. The proposed power-decoupling controller shares the reference for primary side current regulation of the flyback PV inverter. The decoupling controller shapes the input current of the bidirectional buck-boost converter. The shared reference eliminates the phase-delay between the input current to the bidirectional buck-boost converter and the double frequency current at the PV primary current. The elimination of the phase-delay in dynamic response enhances the ripple rejection capability of the power decoupling buck-boost converter even with small film capacitor. With proposed power decoupling control scheme, the additional advantage of the primary-side regulation of flyback PV inverter is that there is no need to have an extra current sensor for obtaining the ripplecurrent reference of the decoupling current-controller of the power-decoupling buck-boost converter. Therefore, the proposed power decoupling control scheme is cost-effective as well as the size benefit. A new transient analysis is carried out which includes the source voltage dynamics instead of considering the source voltage as a pure voltage source. For verification of the proposed control scheme, simulation and experimental results are presented.

• 한국기계가공학회지
• /
• 제3권4호
• /
• pp.20-29
• /
• 2004

A Tool wear monitoring system is indispensable for better machining productivity with guarantee of machining safety by informing the tool changing time in automated and unmanned CNC machining. Different from monitoring using other signals, the monitoring of spindle current has been used without requiring additional sensors on machine tools. For the reliable tool wear monitoring, current signal only of tool wear should be extracted from other parameters to avoid exhaustive analyses on signals in which all parameters are fused. In this paper, influences of force components of parameters on measured spindle current are investigated and a hybrid approach to cutting force regulation is employed for tool wear signal extraction in the spindle current. Finally, wear levels are verified with experimental results by means of real-time feedrate aspects changed to regulate the force component of tool wear.

• 무역상무연구
• /
• 제17권
• /
• pp.93-125
• /
• 2002

This paper aims to find a reasonable solvency margin system in non-life insurance industry and also to evaluate the appropriateness of the current solvency margin regulation system in Korea. The current solvency margin system in Korea, based on EU's solvency margin model, was introduced during the 1997 financial crisis. The solvency requirement is not based on non-life insurer's risk, but simply on written premiums. The current solvency margin for general insurance, such as fire, marine, and automobile insurance, is determined by the greater between a premium-based amount and a claim-based amount, where the premium-based solvency margin is calculated by multiplying the net written premium for the preceding year by the premium based solvency margin ratio. Also, the amount of solvency margin for long term insurance is set at 4% of the policy reserve of the long term insurance. Still, there exist many differences between the current solvency margin regulation system in Korea and EU's model. This paper focuses on the rationality of the solvency margin regulation system, and compares the current system in Korea with EU's model and the RBC(Risk Based Capital) system in U.S. and Japan. Finally, this paper suggests a more specific and reasonable solvency margin system to be developed in Korea.