Dong-Choon Lee

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—This paper proposes a novel control scheme of single-phase-to-three-phase pulsewidth-modulation (PWM) converters for low-power three-phase induction motor drives, where a single phase half-bridge PWM rectifier and a two-leg inverter are used. With this converter topology, the number of switching devices is reduced to six from ten in the case of full-bridge(More)
—This paper presents a new velocity estimation strategy of a nonsalient permanent-magnet synchronous motor (PMSM) drive without a high-frequency signal injection or special pulsewidth-modulation (PWM) pattern. This approach is based on the d-axis current regulator output voltage of the drive system that has the information of rotor position error. Rotor(More)
—In this paper, a novel control scheme of three-phase PWM rectifiers eliminating both the ac input voltage and current sensors is proposed. The phase angle and the magnitude of the source voltage are estimated by controlling the deviation between the rectifier current and its model current to be zero. The input currents can be reconstructed from switching(More)
—Conventional proportional/proportional–integral (P/PI) speed controller for today's servo drives has to be manually tuned at the controller switching set point by trial and error, which may translate into drive system downtime and a subsequent loss of productivity. The adjustable drive performance is heavily dependent on the quality of expert knowledge.(More)
Fig. 3. Start-up performance of the system directly from DVC mode. TMS30C30-type DSP, and the experimental results of the total drive system will be reported in the future. V. CONCLUSION A zero-speed start-up method has been developed and investigated for a speed sensorless induction motor drive that uses stator-flux-oriented direct vector control. The(More)
—In this paper, a novel control scheme compensating for source voltage unbalance and current harmonics in series-type active power filter systems combined with shunt passive filters is proposed, which focuses on reducing the delay time effect required to generate the reference voltage. Using digital all-pass filters, the positive voltage sequence component(More)
—This paper proposes a new maximum power point tracking (MPPT) algorithm for variable-speed wind turbine systems , which takes advantage of the rotor inertia power. In this method, a proportional controller is added to the power control to effectively reduce the moment of inertia of the wind turbines, which can improve the fast performance of the MPPT(More)