• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.1
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• pp.1-8
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• 2000

Switched reluctance motor(SRM) has simple magnetic structure, and requires simple power electronic driving circuit. It is very useful for wide range adjustable speed drive system. But, SRM drive generates large vibration and acoustic noise because it is commutated individually by step pulse m.m.f of each phase pole. In the vibration and acoustic noise characteristics. The considerable vibration and noise is induced by radial deforming of stator, so the frequency of dominant vibration and noise is coincident with the frequency of natural mode frequency of mechanical structure. This radial vibration force is generated in the phase commutation region. This paper suggests the new electromagnetic structure of SRM with auxiliary commutation winding which is excited by direct current. This phase and commutation winding are coupled magnetically between one phase winding and the other. Therefore, the switch-off phase current is absorbed by the another phase winding. By this interaction of phase and commutation winding in commutation mechanism, vibration and noise is reduced. And this reduction effect is examined by the test of prototype machine. As a result, SRM with DC exciting commutation winding is very useful to reduce vibration and acoustic noise.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.243-246
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• 2001

The control of the SRM(Switched Reluctance Motor) is usually based on the non-linear inductance profiles with positions. So determination of optimal switching angle is very different. This paper proposed that the determination method of turn-on/off angle in the SRM drives is to maintain the high torque, which is realized by using self-tuning control method. During the sampling time, a number of pulses from the encoder are checked by using micro-controller. And compared with pre-checked a number of pulses. After calculating difference between two data, turn-on/off angle moves forward or backward direction by using self-tuning method. The optimal turn-on/off angle is determined by iterating such a process and the maximum torque is maintained. Experimental results are provided to demonstrate the validity of the self-tuning controller.

• Proceedings of the KIEE Conference
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• summer
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• pp.959-961
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• 2004

A multi pole SRM(switched reluctance motor) is applied by the regulated current in regular sequence. So, it can be started by itself. But a single phase SRM can not be started by itself because the positive torque is only generated in the limited zone which the inductance is increased. Therefore, it is required auxiliary device for self starting which place the rotor in start position. The prototype was designed and fabricated in the previous research. It has the permanent magnet, which is installed in the bottom of the rotor, for self starting. But the permanent magnet affect the prototype during operation and cause the decrease of the torque and speed. The influence of the permanent magnet on the average torque and speed was already confirmed. On this paper, the instant torque of the prototype was calculated from the experiment results which is the inductance and current according to installed permanent magnet or not.

• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.4
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• pp.307-312
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• 2006

This paper proposes the SRM drive system, which accurately estimates the phase currents from the DC-link current to drive SRM instead of detecting the three-phase currents. In addition, the detecting circuit of DC-link current is also proposed to increase the resolution and decrease the off-set influence. Comparing with the general drive system based on the phase current, it is verified through the experiments that the proposed SRM drive system based on the DC-link current has the good performance in steady-state response of the speed control. Using the DC-link current, all of the 3-phase currents can be easily estimated for driving the SRM.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.5
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• pp.115-121
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• 2014

The intrinsic simplicity, ruggedness, and simple power electronic drive requirement of a Switched Reluctance Motor(SRM) make it possible to use in many commercial adjustable speed application. The simple magnetic circuit results in a high efficiency drive and low temperature rise, and the drive system provides a good drive characteristics. This paper is provides two phase 4/3 SRM that is similar to two phase 6/3 SRM as aspect to magnetic structure. Although 6/3 SRM does not experience any flux reversal as the flux is in the same direction whether phase A or B is excited, but two phase 4/3 SRM experiences a flux reversal in small part of stator yoke. The flux reversal in two phase 4/3 SRM could be relieved by an adjustment of stator yoke structure. The magnetic analysis and design considerations of the two phase 4/3 SRM have been obtained by the finite element method analysis (FEM).

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.3
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• pp.205-212
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• 2007

This paper presents a direct instantaneous torque control (DITC) of Switched Reluctance Motor (SRM) with a novel 4-level converter to develop a uniform torque and to improve a dynamic performance. The DITC method can reduce a high torque ripple of SRM. Drive efficiency and dynamic performance with conventional drive are low due to a slow excitation current build-up. Since the 4-level converter can obtain an addition boosted voltage to have a fast excitation and demagnetization, it can Improve dynamic performance and efficiency easily. To apply the DITC technique to a 4-level converter, a novel control scheme is presented according to the operating modes. Additionally, selection of capacitances of boosted capacitor and efficiency improvement of 4-level converter are analyzed. At last, the validity of proposed method is verified by some computer simulations md comparative experiments.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.4
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• pp.356-361
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• 2008

The conventional drive system of SRM has a current sensor per each phase. The torque demand signal generated by the outer control loop is translated into individual current reference signal for each phase. The torque is controlled by regulating these currents. Using the SRM in a variable-speed control, the phase currents are generally regulated to achieve a square wave. The simplest form of current regulation uses fixed frequency delta modulation of the phase voltages. The aim of this paper is to regulate 3-phases current of SRM by only single current sensor using delta modulation with digital chip. In this paper, the asymmetric bridge converter which is able to control independently phases and be excited simultaneously is used as the driver system for 6/4 poles SRM. And the current sensor is replaced 3 sensors of each phase with only one on bus line of converter so as to detect current of every phase. The proposed delta modulation technique has been implemented in a simple digital logic circuit using EPLD(Electrically Programmable Logic Device). This method is verified through simulation and experiment results.

• Proceedings of the KIPE Conference
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• 2010.11a
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• pp.15-16
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• 2010

본 논문에서는 최소의 진동/소음을 가지는 SRM을 설계하기 위하여 고정자와 회전자의 Skew에 따른 단상 6/6 SRM의 소음/진동 특성을 비교, 분석하였다. SRM(Switched Reluctance Motor)에 발생하는 소음/진동의 주 원인은 모터 구동 시 Yoke 에 발생하는 방사방향 힘의 변화라고 할 수 있다. Yoke에 작용하는 힘은 돌극이 위치한 곳에 집중되므로 더욱 큰 진동을 유발하지만 회전자와 고정자에 동일한 Skew를 적용시키면 힘을 받는 Yoke의 면적은 늘어나게 되고, 따라서 방사방향의 힘을 요크 전체로 분산 시킬 수 있다. 이에 따라 스위치 온, 오프시 요크에 인가되는 방사방향의 힘의 최대치는 감소하게 되어 진동/소음이 현저히 줄어들게 된다. 본 논문에서는 최소의 진동/소음을 가지는 SRM을 설계하기 위하여 시뮬레이션을 통하여 회전자와 고정자의 스큐 각도에 따른 힘의 분포를 분석하였다. 시뮬레이션 결과를 바탕으로 하여 대표적인 특성을 가진 $0^{\circ}$, $18^{\circ}$의 SRM을 설계하여 소음/진동을 측정한 결과 제안한 방식이 소음/진동을 현저하게 감소시키는 효과를 가짐을 입증하였다.

• The Transactions of the Korean Institute of Power Electronics
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• v.13 no.3
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• pp.171-178
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• 2008

Pressure control of hydraulic pump using SRM with pressure predictor and direct torque control method is presented in this paper. Nowadays, high efficiency and high performance motor drive is much interested in hydraulic pump system. But the hydraulic pump system has an inherent defect that its dynamic behavior causes by interaction between the sensor and hydraulic load. It will make low performance of whole system, even unstable and oscillatory. Proposed system integrates pressure predictor and direct instantaneous torque control (DITC). The pressure predictor includes Smith predictor, which is easy to improve unstable or long oscillation in traditional negative feedback control and popular PID control architectures. And DITC method can reduce inherent torque ripple of SRM, and develop smooth torque to load, which can increase stability and improve the torque response of SR drive. So high dynamic performance and stabilization can achieved proposed hydraulic system. At last, the proposed hydraulic system is verified by simulation and experimental results.

• The Transactions of the Korean Institute of Power Electronics
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• v.9 no.3
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• pp.240-245
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• 2004

This paper presents a Switched Reluctance Motor(SRM) drive using the self-tuning control method to achieve the maximum torque. SRM has the difficulty to research it by an analytic method and to control the speed End torque because of the high nonlinearity. So, in this paper, the self-tuning control method is applied to relevantly controlling turn-on/off angle to operate at the maximum torque. Also, the feedback signals to control the turn-on/off angle are the encoder pulse and the increment of phase current. At first, n adequate turn-off angle is searched by itself and then a turn-on angle is done. As the relationship between turn-on and him-off angle is mutual dependent, the turn-on/off angle is controlled by a real time self-tuning control method in order to maintain the maximum torque. The proposed self-tuning Algorithm is verified by experiments.