• Proceedings of the KIEE Conference
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• 2008.04c
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• pp.134-136
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• 2008

In recent years, the switched reluctance motor have been used many industrial application because of its cost advantage. SRM drivers are accomplished by switching the phase currents on and off synchronously with the rotor position which is fed back to the controller by position may deteriorate in harsh environments and increase the size and cost of the SRM drive system. This paper proposes a position sensorless method that is based on impressed pulse voltage using impressed at unenergised phases to estimate the rotor position. The current value by impressed pulse voltage compare with the threshold value. The rotor position can be estimated by observing the current value. Finally, simulation results compare with the sensor type SRM and confirm the proposed method to be useful.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.6
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• pp.292-297
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• 2002

This paper proposes a sensorless drive of a permanent magnet synchronous motor. In general EMF is used to calculate the current of Permanet Magnet Synchronous Motor(PMSM). However the current has a lag component by a time constant. So it is difficult to directly calculate a position angle. To estimate the position using the current without a lag component in this paper, the controller calculates the motor current by using a superposition principle in the equivalent circuit and then compensates lag component with a time constant of the motor. Therefore the estimated motor current without a lag compoent can be obtained and it is used to calculate the rotor position indirectly. In order to confirm the effectiveness of the proposed algorithm, experimental results are shown in detail.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.48 no.3
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• pp.139-143
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• 1999

This paper is on realization of the speed-sensorless vector control of an induction motor using the RLS(Recursive Least Square) algorithm. The speed estimator is including the RLS algorithm and a rotor flux observer. The RLS algorithm has speed and rotor time constant as parameter vectors and rotor flux observer is designed to have robustness to stator resistance variation and through the IP(Integral and Proportional) speed controller stable performance is obtained for estimating rotor speed. Finally the total algorithm are realized in induction motor drive system and its effectiveness is verified.

• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.5
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• pp.440-446
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• 2006

The magnitude of output torque in a BLDC Motor depends on torque angle so that the exact initial position of rotor is essentially required for good starting. This paper presents a novel starting control method for smooth starting in a position-sensorless controlled BLDC motor drive for reciprocating compressor of refrigerator. The proposed method starts a BLDC motor using information on the initial position of rotor, determined from current response characteristics, and shows robust starting capability to starting load variations. The effectiveness of the proposed method is verified through experimental results.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.1
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• pp.100-107
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• 2003

This study was to control magnetic field orientation-typed sensorless vector control by applying the theory of a rotor flux observer to drive an induction motor. This research suggested a new speed estimation method that estimates speed with the rotor flux obtained by using a flux observer and the variable of state current detected by a current sensor without a speed sensor. Because the speed estimation method is independent from the motor constants, it is not necessary to control the gain of the parameters and the algorithm is simple. In the findings of the study, the researcher was convinced of the control function and the possibility of realization in the simulation experiment of sensorless vector control system by using DSP(Digital Signal Prosessor).

• Journal of Power Electronics
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• v.12 no.4
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• pp.604-614
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• 2012

This paper presents a comparative study of position sensorless control schemes based on back-electromotive force (back-EMF) estimation in permanent magnet synchronous motors (PMSM). The characteristics of the estimated back-EMF signals are analyzed using various mathematical models of a PMSM. The transfer functions of the estimators, based on the extended EMF model in the rotor reference frame, are derived to show their similarity. They are then used for the analysis of the effects of both the motor parameter variations and the voltage errors due to inverter nonlinearity on the accuracy of the back-EMF estimation. The differences between a phase-locked-loop (PLL) type estimator and a Luenberger observer type estimator, generally used for extracting rotor speed and position information from estimated back-EMF signals, are also examined. An experimental study with a 250-W interior-permanent-magnet machine has been performed to validate the analyses.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.340-342
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• 2005

This paper describes the speed-sensorless vector control system of a three-phase induction motor using sliding mode flux/speed observer. The sliding mode observer estimates the rotor speed. The error between the actual and observed currents converges to zero which guarantees the accuracy of the flux observer. The convergence of nonlinear time-varying observer along with the asymptotic stability of the controller was analyzed. To define the control action which maintains the motion on the sliding manifold, an "equivalent control" concept was used. It was simulated and implemented on a sensorless indirect vector drive for 750[W] three-phase induction motor. The simulation and experimental results demonstrated the effectiveness of the proposed estimation method.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.579-583
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• 2005

This paper is study for design SOC composing space vector control algorithm of sensorless BLDC motor by H/W and apply this to operating machanism of washing machine system. it is study that increases control efficiency than S/W control algorithm and enhances response for change of system and authoritativeness of controller. Designed so that can compose controller of most suitable in dynamic characteristic of system by design Parameters of each controller to independent block for SOC design connecting to 8051 cores. For control Sensorless BLDC motor to drive system of washing machine, applied to H/W SVPWM control, so improved authoritativeness of control algorithm and control effectiveness than S/W control algorithm

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.881-882
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• 2008

For the interior permanent magnet synchronous motor(IPMSM) drive to operate above the base speed in the constant horsepower region, the field weakening control is applied. However, the field weakening control was not almost applied to sensorless control of the interior permanent magnet synchronous motor. In this paper, the field weakening control is applied to the sensorless control of IPMSM based on the fuzzy controller. The effectiveness of the proposed system is verified by the experimental results.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.175-178
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• 2002

In a conventional speed sensorless Stator Flux Oriented(SFO) induction machine drive system, the estimated speed is delayed in transients by the use of a low pass filter(LPF). To prevent extreme overshoot caused by this delay, PI controller gains should be small, which consequently is greatly affected by disturbance torque. In this paper, by taking advantage of disturbance torque observer and feedforward control, robust speed controller is designed for speed sensorless SFO system. The proposed method is verified by the simulation results.