계통연계형 인버터의 왜곡된 계통전압에 의해 발생하는 전류고조파 저감방법

목형수(H.S. Mok),최규하(G.H. Choe),이정민(J. M. Lee),김상훈(S. H. Kim),지준근(J.K. Ji) 전력전자학회 2007 전력전자학술대회 논문집 Vol.- No.-

Phase angle in grid-connected inverter is important information for current control. When different loads are connected to PCC(Point of Common Coupling) of grid, distorted grid voltage is taken place by load utility generating distorted current. Especially, in case the grid voltage is distorted by low order frequency such as 3<SUP>rd</SUP>, 5<SUP>th</SUP> harmonic, phase angle of PLL output is distorted. This paper analyze problem of current THD(Total Harmonic Distortion) due to distorted phase angle by distorted grid voltage, and propose control method compensating this problem. Also, it’s validity is verified by simulation and experiment.

조건부 적분기를 가지는 LQ 제어기를 이용한 3상 PWM 컨버터의 전류제어

김홍성(H.S Kim),전윤석(Y S. Jeon),조영준(Y.J Joe),목형수(H S. Mok),최규하(G.H Choe),김한성(H.S.Kim) 전력전자학회 1997 전력전자학술대회 논문집 Vol.1997 No.-

In this paper, controller for PWM converter considering unsymetrical input voltage is designed and current controller using LQ controller with conditional integrator is proposed. And the proposed current controller is compared with other current controller predictive controller, decoupling PI controller. As simulation results, LQ controller with Conditional Integrator shows the improved performance for DC link voltage regulation through transient test of load variation. And when unsymeritrical input voltage is applied to converter with conventional current controller considering only symetrical input voltage, input current is distorted but it is showed that current controller considering unsymetrical input has robust control characteristics under phase voltage unbalance.

12펄스 정류기의 DC 전압 안정성 문제 분석

송호재(H. J. Song),박현수(H. S. Park),최재혁(J. H. Choi),목형수(H. S. Mok) 전력전자학회 2025 전력전자학회 학술대회 논문집 Vol.2025 No.7

공간전압벡터 PWM을 이용한 7상 영구자석형 동기전동기의 구동 시스템

김한구(H.G. Kim),최문규(M.G. Choi),정병환(B.H. Jeong),목형수(H.S. Mok),최규하(G.H. Choe) 전력전자학회 2005 전력전자학술대회 논문집 Vol.- No.-

The motor research of pre-existing attaches importance about one and three motor of reduce torque ripple and speed control. 3-Phase PMSM Motor, which is generally used, has limited usage in high speed, due to pulsation torque and variable speed. To solve this problem, it is necessary to increase invariable, pole number or the number of slots. In this paper 7-Phase PMSM Motor of Steady state analysis of Torque and Output Voltage characteristic. 7-Phase modulation method with Space Voltage Vector is studied for ideal operation of controller.

인버터 아크용접기를 위한 3상 승압/강압형 컨버터의 운전특성비교

최해룡(H.R. Choi),구영모(Y.M. Goo),채영민(Y.M. Chae),최규하(G.H. Choe),목형수(H.S. Mok),김규식(K.S. Kim),원충연(C.Y. Won) 전력전자학회 1998 전력전자학술대회 논문집 Vol.- No.-

Three phase Boost/Buck converter which have economical merits and simple control scheme, are analyzed and evaluated through comparative methods and digital simulation for equivalent load Those play a part of voltage boost/buck as well as power factor correction with single switch. Controller operating in constant and variable frequency is used for rapid output response and stable system condition respectively Moreover low THD property of single switched converter is available for inverter arc welding machine known as high power and low power factor. So in this paper a comparison of the characteristics in boost and buck converter is described and then simulation results conforms the merits from the point of view of power factor and voltage regulator.<br/> <br/>

비선형 역기전력 파형을 고려한 BLDC 모터 모델

이상용(S.Y. Lee),강병희(B.H. Kang),채영민(Y.M. Chae),목형수(H.S. Mok),초규하(G.H. Choe),김덕근(D.K. Kim),류재성(J.S. Ryu) 전력전자학회 1999 전력전자학술대회 논문집 Vol.1999 No.7

A brushless DC motor has the high quality of torque output and silence, has been more widely used in industrial area. As the driver and controller of BLDC motor have been more complicated and precise, simulation method has been much used m motor design. And the output characteristics of BLDC motor is determined by the waveform of BACK-EMF in instinct. But because the conventional model of BLDC motor is obtained by approximation of real nonlinear waveform to ideal trapezoidal waveform, the error is occurred in slmulation result. Thus in this paper, for the correction of this error in simulation, the model of real nonlinear waveform considered is proposed, and the simulation result is obtained in case of three-phase, four-poles Y-connected, surface mounted permanent magnet BLDC motor.

리튬 폴리머 전지의 충방전 특성해석

최룡해(H.R. Choi),강병희(B.H. Rang),목형수(H.S. Mok),최규하(G.H. Choe),신우석(W.S. Shin) 전력전자학회 1999 전력전자학술대회 논문집 Vol.1999 No.7

Started upon Its discovery by Wright et al in 1973, studies on the solid polymer electrolyte are being carried out vigorously. So. models of Ll-polymer battery have been developed through R-L-C components combination and P-splce functional block in this paper. The Impedance characteristics of Li-polymer battery with R-L-C components are presented. Simulation results using P-spice functional model are compared with measured charge/discharge characteristics.

MSTC를 이용한 7상 BLDC 모터 구동시스템

이석(S. Lee),전윤석(Y.S. Jeon),김흥민(H.M. Kim),목형수(H.S. Mok),김덕근(D.G. Kim) 전력전자학회 2000 전력전자학술대회 논문집 Vol.2000 No.11

Recently, the demand of motor for industrial, household machinery is increasing. As switching devices and control technology are progressing, so the use of BLDC Motor is increasing But 3- Phase BLDC Motor generally used has pulsating torque and speed variation in commutation, so the range of it's application is limited high speed application is Especially, to solve these problems, it is necessary to increase phase of Motor, so study of Poly-Phase BLDC Motor is progressing. In this paper, we designd 7-Phase BLDC Motor drive system and MSTC(Minimum Switching Time Controller)

마이크로 프로세서를 이용한 축전지의 병렬운전 부하분담률 개선에 관한 연구

반한식(H.S. Ban),이정민(J.M. Lee),목형수(H.S. Mok),최규하(G.H. Choe) 전력전자학회 2000 전력전자학술대회 논문집 Vol.2000 No.11

A battery is the device that transforms the chemical energy into the direct-current electrical energy without a mechanical process. Unit cells are connected in series to obtain the required voltage, while being connected in parallel to organize capacity for load current. Because the voltage drop down in one set of battery is faster than in two one, it may result in the low efficiency of power converter with the voltage drop and cause the system shutdown. However, when the system being driven in parallel, a circular-current can be generated. It is shown that, as a result the new batteries are heated by over-charge and over-discharge, and the over charge current increases rust of the positive grid and consequently shortens the lifetime of the new batteries. The difference between the new batteries and old ones is the amount of internal resistance. In this paper, we can detect the unbalance current using the microprocessor and achieve the balance current by adjusting resistance of each set. The internal resistance of each set becomes constant and the current of charge and discharge comes to be balanced by inserting the external resistance into the system and calculating the change of internal resistance.

불평형 전원시스템을 고려한 3상 능동전력 필터에 관한 연구

이승요(S.Y.Lee),조준석(J.S.Cho),최규하(G.H.Choe),목형수(H.S.Mok),박영길(Y.K.Park),신우석(W.S.Shin) 전력전자학회 1997 전력전자학술대회 논문집 Vol.1997 No.-

An important assumption for the active power filter design using instantaneous power theory and the d-q transformation method in a 3-phase power system is based on balanced 3-phase system. However, under pratical conditions, the 3-phase power system can not be continuously balanced due to unbalanced loading. In this paper, a method to control the 3-phase active power filer using instantaneous power theory and the d-q transformation under unbalanced power system is presented and the theoretical results are verified by simulated results.