• Journal of Electrical Engineering and Technology
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• v.4 no.2
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• pp.266-271
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• 2009

In this paper, improved direct torque control(DTC) of five-phase induction motor(IM) is proposed. Due to the additional degrees of freedom, five-phase IM drives present unique characteristics. One of them is the ability of enhancing the torque producing capability of the motor. Also five-phase motor drives possess many others advantage compared with the traditional three-phase motor drives. Such as, reducing the amplitude and increasing of frequency of torque pulsation, reducing amplitude of current per phase without increasing the voltage per phase and increasing the reliability. The direct torque control method is advantageous when it is applied to the five-phase IM. Because the five-phase inverter provides 32 space vectors in comparison to 8 space voltage vectors by the three-phase inverter. The 32 space voltage vectors are divided into three groups according to their magnitudes. The characteristics and dynamic performance of traditional five-phase DTC are analyzed and new DTC for five-phase IM is proposed. Therefore, a more precise flux and torque control algorithm for the five-phase IM drives can be suggested and explained. For presenting the superior performance of the pro-posed direct torque control, experimental results is presented using a 32 bit fixed point TMS320F2812 digital signal processor

• Journal of Power Electronics
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• v.16 no.6
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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.

• Journal of Korean Medical classics
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• v.23 no.1
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• pp.15-19
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• 2010

Five phase theory has significant effect on Traditional Chinese Medicine, which puts its emphasis on correlation and integrity. However, the five phase theory itself has a limitation that it cannot reflect the general correlation and special features of affairs. Traditional Chinese Medicine pertains the five organs to five elements, absorbing the essence of the five phase theory, and transcending the limitation of the five phase theory in practice. Therefore, Traditional Chinese Medicine and other traditional medicine theories can be called as "five viscera correlation theory". On the course of modernization of traditional medicine, the effects among the five viscera can be concluded to 3 correlations of promotion, coordination and inhibition, to illustrate the integrity and correlation theory of traditional medicine from different approaches.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.2
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• pp.138-147
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• 2009

In this paper, improved direct torque control(DTC) system for five-phase squirrel-cage induction motor(IM) is proposed. Due to the additional degrees of freedom, five-phase 1M drives present unique characteristics. Also five-phase motor drives possess many other advantages compared with the traditional three-phase motor drive system, such as reducing an amplitude of torque pulsation and increasing the reliability. The DTC method is advantageous when it is applied to the five-phase IM, because the five-phase inverter provides 32 space vectors in comparison to 8 space voltage vectors into the three-phase inverter. However, five-phase motor has structural drawback of 3rd space-harmonics current component, it is necessary to controlled 3rd harmonic current. So to control 3rd harmonic current and enhance dynamic characteristics of five-phase squirrel-cage IM drive, modified DTC method should be demanded. The characteristics and dynamic performance of traditional five-phase DTC are analyzed and new DTC for five-phase IM is presented. A more precise flux and torque control algorithm for the drives can be suggested and explained For presenting the superior performance of the proposed direct torque control, experimental results are presented using a 32-[bit] fixed point TMS320F2812 digital signal processor with 2.2[kW] induction motor.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.95-97
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• 2006

This paper investigates the field weakening operation of a five-phase IPMSM(inner permanent magnet synchronous motor). The five-phase motor can supply sinusoidal voltage and third harmonic voltage because of more freedom of control. This paper present field weakening algorithm and experimental results for five-phase IPMSM which has trapzoidal back-EMF and concentrate winding to prove the validity of the proposed algorithm.

• Korean Journal of Acupuncture
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• v.39 no.2
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• pp.63-67
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• 2022

Objectives : The purpose of this study was to investigate the needling depth of five-phase acupoints and discuss the association with the depth of meridian qi. Methods : DongUiBoGam was used to determine the depth of five-phase acupoints. The depth of needling at 60 five-phase acupoints was compared between well, spring, stream, river, and sea acupoints. Results : The proximal part of the extremities had deeper needling depth than the distal part of the extremities. The targeted deqi sensation can be related to the needling depth. Conclusions : The depth of the meridian qi is related to the distinct patterns of needling depth of five-phase acupoints.

• Korean Journal of Acupuncture
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• v.32 no.2
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• pp.66-74
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• 2015

Background : Saam acupuncture were composed by applying the elemental concepts from the Five Phase theory - the relationships between the cycles such as Saeng(Sheng, 'nourishing' or 'creating') and Geuk(Ke, 'suppressing' or 'controlling') - onto the Five Phase points and 12 channels to compensate for the imbalance in each of the 12 main energy traits. Objective : The present study is aimed to find out the characteristics of Five Phase points pattern in Saam acupuncture. Methods : We analysed the characteristics of five elements of the Five Phase points in Korean medical texts such as Saamdoinchimguyogyeol, Dongeuibogam and Chimgugyeongheombang in mid Chosun Dynasty. Using non-negative factorization(NNMF) methods, we extracted the feature matrix of five elements of Five Phase points in each classic medical text. Results : In Saam acupuncture, two characteristics were most prominent: (1) "Self" component of Five elements, (2) "Mother" and "Grandmother" component of Five elements. Conclusions : Saam acupuncture used the combination of Five-Shu acupoint based on ZangFu pattern identification. Our findings suggest that grasping the characteristics of Five Phase points combinations can improve the understanding the selection of the relevant acupoints based on the ZangFu pattern identifications.

• Korean Journal of Acupuncture
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• v.39 no.4
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• pp.117-125
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• 2022

Objectives : The purpose of this study was to investigate the needling depth of five-phase acupoints by acupuncture and moxibustion literatures. Methods : 7 volumes of acupuncture and moxibustion literatures was used to determine the depth of five-phase acupoints. The depth of needling at 60 five-phase acupoints was compared between well, spring, stream, river, sea acupoints and also yin, yang, hand and foot meridians. Results : The proximal part of the extremities had deeper needling depth than the distal part of the extremities. The order of well, spring, stream, river, sea can be related to the needling depth. Foot meridians had deeper needling depth than hand meridians. Yin meridians had deeper needling depth at Well, spring, stream acupoints and yan meridians had deeper needling depth at river, sea acupoints. Conclusions : The distinct patterns of needling depth of five-phase acupoints is related to which part of the extremities are five-phase acupoints located.

• Journal of Power Electronics
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• v.11 no.3
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• pp.294-303
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• 2011

In this paper an effective five-phase induction motor (IM) and its drive methods are proposed. Due to the additional degrees of freedom, the five-phase IM drive presents unique characteristics for enhancing the torque producing capability of the motor. Also the five-phase motor drives possess many other advantages when compared to traditional three-phase motor drives. Some of these advantages include, reducing the amplitude and increasing the frequency of the torque pulsation, reducing the amplitude of the current without increasing the voltage per phase and increasing the reliability. In order to maximize the torque per ampere, the proposed motor has concentrated winding, the produced back electromotive force (EMF) is almost trapezoidal, and the motor is supplied with the combined sinusoidal plus the third harmonic of the currents. For demonstrating the superior performance of the proposed five-phase IM, the motors are also analyzed on the synchronously rotating reference frame. To supply trapezoidal current waveform and to exclude the effect of the $3^{rd}$ harmonic current, a new control stratagem is proposed. The proposed control method is based on direct torque control (DTC) and rotor flux oriented control (RFOC) of the five-phase IM drives. It is able to reduce the acoustical noise, the torque, the flux, the current, and the speed pulsations during the steady state. The DTC transient merits are preserved, while a better quality steady-state performance is produced in the five phase motor drive for a wide speed range. Experimental results clearly demonstrated a more dynamic steady state performance with the proposed control system.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.1
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• pp.66-74
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• 2012

This paper propose a improved direct torque control(DTC) system for improving operation of five-phase squirrel-cage induction motor(IM). A five-phase IM drives present unique characteristics due to the additional degrees of freedom and also drives possess many others advantage compared with the traditional three-phase motor drive system, such as reducing a amplitude of torque pulsation and increasing the reliability. In order to maximize the torque per ampere, the proposed motor has concentrated windings and the produced back-electromotive force(EMF) is almost trapezoidal, and the motor is supplied with the combined sinusoidal plus third harmonic of currents, there is necessary to controlled 3rd harmonic current. Also a DTC method is advantageous when it is applied to the five-phase IM, because the five-phase inverter provides 32 space vectors in comparison to 8 space voltage vectors into the three-phase inverter drive system. For presenting the superior performance of the proposed DTC, experimental results of speed control are presented using a 32-bit fixed point TMS320F2812 DSP with 1.5[hp] IM.