• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 F
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• pp.2776-2779
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• 1999

This paper describes the vector control of a single-phase induction motor drive system to improve the dynamic performance for low power applications. Using auxiliary winding which is only utilized for starting, the single-phase induction motor is regarded as the unsymmetrical two-phase motor. This paper shows that the vector control of single-phase induction motor with new method achieves the high performance of the motor. The results of the new method are illustrated by the simulations.

• 전력전자학회논문지
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• 제10권4호
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• pp.339-346
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• 2005

본 논문에서는 3-레그 2상 인버터의 새로운 PWM방식을 제안하였다. 기존의 3-레그 인버터의 PWM방식은 전형적인 SVPWM 방식을 적용하여 PWM 방식이 복잡하다. 3-레그 2상 인버터를 "중성점이 있는 4-레그 인버터"의 등가회로라고 할 때 3-레그 인버터에서 형성되는 6개의 섹터는 4개의 섹터로 축소되며, 각 영역에서는 SYPWM 방식 대신 단순화된 정현파형 PWM방식을 적용할 수 있다. 각 레그의 스위치마다 스위칭 시간을 계산하는 스위칭 패턴을 제시하였다. 제안된 ,3-레그 인버터의 PWM방식에 대한 타당성을 확인하기 위해 모의 실험과 실험이 실행되었다.

• 전기학회논문지
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• 제64권8호
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• pp.1186-1192
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• 2015

This paper proposes an economical method that the phase currents can be measured and reconstructed by means of the leg-shunt resistors in the 3-leg 2-phase vector-controlled inverter for 2-phase induction motor. In general, the phase currents of 2-phase induction motor have been measured using two Hall current sensors. However, because Hall current sensors are expensive, economically disadvantageous to apply in low power applications. The proposed method is verified by computer simulations and experiments to show the good performance of the vector control.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1095-1097
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• 1993

The double excited induction motor has two sets of three-phase system : One is connected to the ac source to take care of energy convertion, and the other is to the inverter controlable frequency and/or magnitude of voltage, both of the induction mode and the synchronous mode are possible in double excitation motor, and the proposed double excitation motor can be driven as a synchronous motor by the extra three-phase input. At the synchronous mode the efficiency is improved so higher than that at induction mode or induction motor. The rating of the inverter used for speed control can be reduced upto one-fifth of that for conventional induction motor. Also the cost and maintenance fee of double excitation induction motor can be reduced compared to any other motors.

• Journal of Power Electronics
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• 제16권6호
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• pp.2162-2172
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• 2016

This paper presents a Direct Torque Control (DTC) strategy for the five-phase induction motor driven by a three-level five-phase inverter in order to improve the performance of the five-phase induction motor. In the proposed DTC technique, only 22 voltage vectors out of 243 available voltage vectors in a three-level five-phase inverter are selected and are divided in 10 sectors each with a width of $36^{\circ}$. The four different DTC combinations (DTC-I, II, III and IV) for a three-level five-phase induction motor drive are investigated for improving the performance of five-phase induction motor. All four of the DTC strategies utilize a combination of the same large and zero voltage vectors, but with different medium voltage vectors. Out of these four techniques, DTC-II gives the best performance when compared to the others. This DTC-II technique is analyzed in detail for improvements in the performance of five-phase induction motor in terms of torque ripple, x-y stator flux and Total Harmonics Distortion (THD) of the stator phase current when compared to its two-level counterparts. To verify the effectiveness of the proposed three-level five-phase DTC control strategy, a DSP based experimental system is build. Simulation and experimental results are provided in order to validate the proposed DTC technique.

• 전기학회논문지
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• 제65권7호
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• pp.1204-1210
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• 2016

The phase currents must be accurately measured to achieve the instantaneous torque control of AC motors. In general, those are measured using the current sensors. However, the measured current signals can include the offset errors and scaling errors by several components such as current sensors, analog amplifiers, noise filter circuits, and analog-to-digital converters. Therefore, the torque-controlled performance can be deteriorated by the current measurement errors. In this paper we have analyzed the influence caused by vector control of 2-phase induction motor when two errors are included in measured phase currents. Based on analyzed results, the compensation method is proposed without additional hardware. The proposed compensation method was applied vector-controlled inverter for 2-phase induction motor of 360[W] class and verified through computer simulations and experiments.

• Journal of Electrical Engineering and Technology
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• 제9권1호
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• pp.121-126
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• 2014

The accurate determination of induction motor efficiency depends on the estimation of the five losses of stator and rotor copper loss, iron loss, mechanical loss and stray load loss. As the mechanical and stray load losses are not calculated by electro-magnetic analysis, the values of these two losses are very important in induction motor design. In this paper, the values of mechanical loss and stray load loss are proposed through investigating testing data from commercial products of three phase induction motors under 37kW. If the values of this paper are applied to motor design, the accuracy of design and analysis can be improved. The losses of motors are obtained by using load and no-load test results following IEC 60034-2-1 standard.

• 한국산학기술학회논문지
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• 제16권1호
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• pp.634-638
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• 2015

2상 유도전동기의 벡터제어를 위해서는 전동기로 입력되는 상전류를 실시간으로 측정해야 한다. 일반적으로 전동기의 상전류는 인버터의 출력단에 2개의 홀전류센서를 삽입하여 측정한다. 그러나, 홀전류센서는 가격이 비싸고, 2상 유도전동기용 벡터제어 인버터는 주로 시스템의 가격이 낮은 저전력 응용분야를 대상으로 연구가 진행되고 있으므로 홀전류센서를 사용하는 것은 경제성 측면에서 부적합하다. 따라서, 본 논문에서는 인버터의 출력단에 고가의 홀전류센서 대신 션트저항을 삽입하고, 이것의 양단 전압을 차동 증폭기로 증폭하여 모든 운전영역에서 정밀하게 상전류를 측정하는 방법을 제안한다. 이를 220[V]/360[W]급의 2상 유도전동기 벡터제어 인버터에 적용하였으며, 제안된 방법의 유효성은 컴퓨터 시뮬레이션과 실험을 통하여 검증하였다.

• 전기학회논문지
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• 제63권9호
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• pp.1317-1320
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• 2014

In case of using three-phase induction motor in three-phase power system, if he deficiency happens in phase among three-phase, the motor will drive in an open phase state. As to the motor, the continuing operation is possible then, but the phenomenon that the power supply stops happening by the result of the overload electricity order on the healthy phase of two phases with a damage and activating the circuit breaker. Consequently, in order to overcome this problem in treatise accordingly. I propose an uninterruptible power supply which is able to prevent that the over current on the health phase through the restoration that in case happening open phase on the power line when driving the motor. Also, it is possible to supply power consecutively without interruption of electric power and we proved the performance and reliability through an experiment.

• 전력전자학회논문지
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• 제7권1호
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• pp.1-10
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• 2002

본 논문에서는 2상 인버터용 공간전압벡터 PW 방식을 제안하였다. 제안된 2상 공간전압벡터 PWM 방식은 2상 유도전동기에 적용할 수 있다. 2상 공간전압벡터 방식을 사용하는 2상 인버터는 4개의 공간 전압벡터를 발생하나 영 전압 벡터는 만들 수 없다. 2상 인버터에서는 4개의 공간 전압벡터를 조정하여 기본 전압벡터를 실현한다. 또한, 2상 공간전압벡터방식에 의해 최적의 PWM 전압파형을 만들기 위한 대칭변조방식이 제안되었다. 제안된 2상 공간 전압벡터방식에 대한 타당성을 확인하기 위해 시뮬레이션과 실험이 실행되었다.