• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.58-60
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• 1998

This paper analyzes the torque characteristics with the structure of harmonic side drive motor using by F.E.M and conformal mapping method. F.E.M and conformal analysis result are almost same. Through the results, we investigate how do design parameters variation affect torque characteristics.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권3호
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• pp.104-109
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• 1999

In order to design and predict the performance of the harmonic side drive motor, it is necessary to analyze the torque generated by the structure. In this paper, an analytical model is proposed for design. Conformal mapping is used to model the capacitance and torque of the motor as a function of the rotor angular position with two-dimensional approximation. Then the result of conformal mapping analysis is verified with F.E.M result.

• 전기학회논문지P
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• 제67권1호
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• pp.1-8
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• 2018

ACL and DCL are have been conventionally used for reducing harmonic current on the input side of an ACMD. The current distortion ratio ITHD using ACL and DCL is only 35% to 85%, therefore to satisfy the IEEE Std. 519 requirements, the line filters has been focused as an alternative means. Those are installed between the AC power supply and the input of the ACMD, and must meet the IEEE Std. 519, be economical and be compact. To contribute to the widespread of using these line filters, we discussed concerning its topologies, simulation results, prototype test results as well as the cost evaluations. It included not only the proposed (NHHF) new hybrid harmonic filters which have both merits of simplicity and economic but also the past (BBHF) broadband harmonic filters and (HHF) hybrid harmonic filters.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.409-413
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• 1988

In this paper a control technique for active power filters is proposed which not only eliminates the harmonic current, but also controls the reactive power at the ac side of PWM inverter-induction motor drive system. Injecting the proposed PWM current enables the harmonic components of orders not greater than the pulse number per half-cycle to be removed completely. It also enables the input power factor to become unity. Theoretical investigations are performed to evaluate the performance of the proposed control technique.

• 전력전자학회논문지
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• 제9권5호
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• pp.430-437
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• 2004

본 논문에서는 고주파 스위칭 시 스위칭 손실의 감소, 구현의 용이성 및 인버터 제어를 위하여 요구되는 연산시간 감소 등 다양한 장점을 가진 4-Switch 인버터를 대상으로, 새로운 2상 스위칭 패턴(Pattern)과 이에 적용된 새로운 SRP-PWM(Separately Random Pulse Position PWM)기법을 제안한다. 본 논문에서는 고속운전 영역에서의 인버터 출력전류의 고조파 스펙트럼을 넓은 주파수 영역으로 즉, 특정주파수의 side-band로 고루 분산시키는 결과로부터 제안한 스위칭 패턴과 이에 적용된 새로운 SRP-PWM기법의 고조파 저감효과를 확인하고자 한다. 따라서 DSP를 이용한 IGBT인버터에 의한 실험을 수행하고, 이로부터 얻은 결과를 MATLAB/SIMULINK를 이용한 시뮬레이션 결과와 비교ㆍ분석하여 제안된 기법의 타당성을 검증하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.67-69
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• 1998

In order to design or predict the performance of a cylindrical electrostatic motor it is necessary to analyze the torque generated by such a structure. In this paper a simple but sufficiently accurate analytical model is developed for use in design. Conformal mapping are used to model the capacitance and torque of the motor as a function of the rotor position, using a quasi-static, two-dimension approximation, the effect of an insulating dielectric layer on the stator or rotor is also evaluated.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권8호
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• pp.431-439
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• 1999

Among the variable-speed AC motor drive systems, the static slip power recovery system has been widely adopted in large power drives because a high efficiency drive can be obtained by recovering the slip power to the AC line. Although many improvements have been made in this system, several problems also remain such as the need of transformer in inverter AC side, which results in limiting speed control range and increasing the losses, production of reactive power by the control of inverter firing angle, harmonics in line currents, and so on. This paper presents the novel high performance slip power recovery system using the boost converter and small size filter in the rotor circuit, which recovers slip power of a wound rotor induction machine to AC supply efficiently with the aid of the boost converter, in which most of the problems in conventional system can be solved. The speed can be controlled by the duty ratio of the converter switch, not by inverter firing angle. As a results, the proposed system can operate in high power factor and the harmonic currents caused by the inverter and rectifier can be considerably suppressed. The validity of the proposed system verified by demonstrating the good agreement in the simulation and experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.491-494
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• 1994

The 3-level inverter is applied to the induction motor drive as the voltage type inverter for large poller one. This inverter divides the DC link voltage into the two parts and it is supplied to the inverter. The 3-level inverter can reduces the voltage between the each devices, and get more sinusoidal current waveform. This paper presents the new PWM method which can reduces the harmonics. The modulation at the inverter side is implemented using a DSP microprocessor.