• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.4
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• pp.323-330
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• 2005

In order to increase reliability and reduce system cost, this paper studies particularly applicable method for sensorless PM BLDCM drive system. The waveform of the motor internal voltages(or back emf) contains a fundamental and higher order frequency harmonics. Therefore the third harmonic component is extracted from the stator phase voltage. The resulting third harmonic signal keeps a constant phase relationship with the rotor flux for any motor speed and load condition, and is practically free of noise that can be introduced by the inverter switching, making this a robust sensing method. In addition, a simple starting method and a speed estimation approach are also proposed. Some experimental results are Provided to demonstrate the validity of the proposed control method.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.4
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• pp.201-207
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• 2005

This paper has investigated the sensorless vector control method of induction motor based on the stator flux oriented voltage equation and the digital low pass filter (LPF) with compensator of phase/gain. The Proposed vector control method is easy to decide the stator reference voltages and control of motor, since it is based on stator flux vector But this method has sensitive structure to excessive sensor noise and PWM pulsating components of stator currents because the measured stator currents are directly used to compensate the internal resistive voltage drop at the determination of stator reference voltages. To eliminate the noise sensitive of proposed vector drive, this paper propose the digital LPF with compensator of phase/gain base on orthogonal property of stator current vector in stationary $\alpha$, $\beta$ reference frame. The proposed methods have been simulated and implemented on a sensorless vector drive for 750W three-phase induction motor. The simulation and experimental results demonstrate effectiveness of the proposed methods.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1614-1622
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• 2014

A novel equivalent flux sliding-mode observer (SMO) is proposed for dual three-phase interior permanent magnet synchronous motor (DT-IPMSM) drive system in this paper. The DT-IPMSM has two sets of Y-connected stator three-phase windings spatially shifted by 30 electrical degrees. In this method, the sensorless drive system employs a flux SMO with soft phase-locked loop method for rotor speed and position estimation, not only are low-pass filter and phase compensation module eliminated, but also estimation accuracy is improved. Meanwhile, to get the regulator parameters of current control, the inner current loop is realized using a decoupling and diagonal internal model control algorithm. Experiment results of 2MW-level DT-IPMSM drives system show that the proposed method has good dynamic and static performances.

• Journal of Power Electronics
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• v.10 no.2
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• pp.171-175
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• 2010

This paper introduces the application of a SUI PID controller for permanent magnet (PM) drive systems. The drive system model is developed via FO control. Simulation of the system is carried out to predict the performance at no load and under load. The results and comparisons indicate that application of a SUI PID controller is effective for sensorless PM drive systems.

• Proceedings of the KIEE Conference
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• 2004.10a
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• pp.46-48
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• 2004

Recently, the study of sensorless drive of IPMSM is coming to be active. In sensorless drive, because the wrong estimation of the initial rotor position brings about the decrease of the starting torque, or a temporary reverse revolution, it is important to know the exact importation of the initial rotor position. In this paper, the initial rotor position estimation method is based on the current peak measured by applying the pulsewise voltage and the current peak is changed according to the rotor position owing to the saliency of the rotor. The effectiveness of the proposed algorithm is verified by the experimental results.

• The Transactions of the Korean Institute of Power Electronics
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• v.3 no.3
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• pp.199-205
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• 1998

Brushless DC motors have trapezoidal back-EMF waveform. Theoretically it should be fed with rectangular phase current in order to produce torque ripple free. Because it is drived by a voltage source inverter, perfect rectangular phase current can not available and therefore produce torque ripple. In this paper, the torque ripple due to commutation is analyzed and the practical method that can reduce the torque ripple is proposed. Experimental and simulation results show the effectiveness of the proposed method.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.1
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• pp.50-56
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• 2005

This paper develops a sensorless BLDCM drive for frequently startup. The position information is based on detecting the zero-crossing point of the BEMF that can be directly obtained from the terminal voltage of the floating phase without voltage-dividing and filtering. As a result, this approach makes it possible to detect the rotor position over a wide speed range, especially at a lower speed. A fast startup procedure is also discussed because the induced BEMF signals are not present when motor is at rest. Experimental results shows that the schemes implemented are feasible and the performance achieved are satisfactory.

• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.1
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• pp.83-90
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• 2013

This paper describes advanced brushless DC motor drive without position sensor for home appliances with compressor to reduce the pulsating currents and vibration. The proposed method limits the motor currents during starting period and reduces commutation torque ripple during sensorless operating period. Experimental results show that the proposed method implemented in an inverter for a BLDC motor driven compressor considerably reduces not only the pulsating currents but also vibration of the home appliances.

• Proceedings of the KIEE Conference
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• 2004.04a
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• pp.173-176
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• 2004

This paper is proposed to position and speed control of interior permanent magnet synchronous motor(SPMSM) drive without mechanical sensor. A adaptive fuzzy controller is applied for speed control of SPMSM drive A adaptive state observer is used for the mechanical state estimation of the motor. The observer was developed based on nonlinear model of SPMSM, that employs a d-q rotating reference frame attached to the rotor. A adaptive observer is implemented to compute the speed and position feedback signal. The validity of the proposed sensorless scheme is confirmed by various response characteristics.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.129-132
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• 2002

The first purpose of this paper is to develop the sensorless drive at adjustable speed without any mechanical position or speed sensor. For this, this research analyzes terminal voltage, finds the rotor position information and makes the source of commutations of phase current. The second purpose is to propose the sensing method of initial rotor position without instantaneous rotating. Experimental results show the validity and practical use of the proposed sensing method.