• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.53 no.3
• /
• pp.123-127
• /
• 2004

Mode conversion type ultrasonic rotary motor using bolt tightened Langevin type vibrator was studied. Driving frequency of the motor, displacements and elliptical trajectories at tip of the coupler were simulated by finite element analysis program (ANSYS). Speed and torque of the fabricated motor were measured as functions of input voltage and load. As results, from FEA the driving frequency of 40.8[kHz] and useful elliptical trajectories were found. Fabricated motor rotated clockwise at frequency of 38.2[kHz]. Speed and torque of the motor were increased when the input voltage was increased. Maximum speed, torque and efficiency were 75[rpm], 0.14[Nm] and 6.28[％], respectively.

• Proceedings of the KIEE Conference
• /
• 2000.07e
• /
• pp.79-84
• /
• 2000

This paper presents an implementation of digital position control system for an induction motor vector drives by a direct torque control(DTC) using the 16bit DSP TMS320 F240. The DSP controller enable enhanced real time algorithm and cost-effective design of intelligent controller for motors which can be yield enhanced operation, fewer system components, lower system cost, increased efficiency and high performance. The system presented are stator flux and torque observer using current model that inputs are current sensing of motor terminal and rotor angle for a low speed operating area, two hysteresis controller, optimal switching look-up table, and IGBT voltage source inverter by fully integrated control software. The developed control system are shown a good motion control response characteristic results and high performance features using 2.2Kw general purposed induction motor.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.667-668
• /
• 2015

Synchronous Reluctance Motor (SynRM) has a simple structure with high efficient and without rotor conductor loss. Therefore, it is better than induction motor for electric vehicle (EV) on aspect of efficiency. SynRM usually operates on the constant torque region using maximum torque per ampere （MTPA）control which is adopted due to rotor structure limitation. Thus, the accurate current angle is crucial for motor control. However, finite element analysis (FEA) program is not sufficient exactly to regard how the iron loss and magnetic saturation influences on the current angle. Consequently, this paper proposed a method to calculate the current angle with consideration of iron loss.

• Proceedings of the KIPE Conference
• /
• 2003.07b
• /
• pp.832-835
• /
• 2003

This paper presents a design and characteristics analysis of a SRM drive for EPS(Electrically Power Steering) application. A conventional driving room space and mechanical structure are suggested in design stage. In the restricted design conditions, motor parameters are determined for sufficient torque and speed. For the smooth torque generation and simple circuit of power system, 12/8 motor drive is considered. With FEM and magnetic circuit analysis, designed motor is simulated to meet the requirement of specifications. Effectiveness of the suggested SRM drive for EPS application is verified by the manufactured prototype motor drive tests.

• Proceedings of the KIPE Conference
• /
• 1998.07a
• /
• pp.305-308
• /
• 1998

This paper describes a development of interior permanent magnet synchronous motor (IPMSM) and driver for electric vehicle (EV) which is driven by 2 motors without differential gear. A inverter is designed to drive 2 motors with 6 legs IGBT switches in a control board. Also vector control algorithm is implemented with maximum torque control method in the constant torque region and field weakening control method considering inverter capacity in the constant power region. Prototype IPMSM and inverter have been developed. To verify dynamic characteristics of the those about torque to speed and efficiency etc. We are making an experiment on that. Though that is not completed, we will show results to be acquired.

• New & Renewable Energy
• /
• v.6 no.4
• /
• pp.41-49
• /
• 2010

Over the last decade, wind turbine industry has rapidly increased around world. These days many parts of the wind generators are induction generator. But it has some problems such as gearbox failure, rotor excitation and maintenance. Thus many manufacturers are considered permanent magnet synchronous generator named PMSG and direct drive. PMSG uses NdFeB magnet has many the advantage compare with induction generator. In this study, 3MW class outer rotor type PMSG for wind turbine is proposed. The generator features 2.6m stator outer radius, 1200mm stator length, 81 pole pairs, 14 rated rpm, 42kN/$m^2$ shear force density and 94.2% efficiency. Design and analysis generator using FEM program. Then calculate and derivate no load voltage, losses, conductor temperature. To reduce total harmonic distortion and cogging torque, the stator is applied the stator skewing. And to evaluate the designed generator, compare with other generators by active mass per rating torque and torque density.

• Journal of the Korean Society of Visualization
• /
• v.7 no.2
• /
• pp.47-55
• /
• 2010

In this study, we optimized the shape of the surface aerator that will be installed in a biological reactor using the response surface method. Response surfaces of mass flow rate, impeller torque, mass flow rate per impeller torque are generated and used to track the optimum shape of the aerator. MOGA(Multi-Objective Genetic Algorithm)method is adopted to find the optimum results. By increasing the mass flow rate per impeller torque, increase of oxygen supply efficiency to a reactor is anticipated. To verify the usability of the surface aerator, PIV measurements on flow fields inside a scale-downed biological reactor model are carried out.

• Proceedings of the KIEE Conference
• /
• 1988.07a
• /
• pp.133-136
• /
• 1988

In this paper, the characteristics of brushless DC Motor using voltage source inverter are analysized. The optimal commutation angle for Maximum Torque, the pulse width of supply voltage for available torque and the advanced commutation according to motor speed and electrical time constant effect power factor, efficiency, and no load speed limit.

• Proceedings of the KIEE Conference
• /
• 2004.10a
• /
• pp.18-20
• /
• 2004

An interior permanent magnet synchronous motor (IPMSM) is receiving increased attention for many industrial applications because of its high torque to inertia ratio, superior power density, and high efficiency. IPMSM is necessary to use the accurate information of the inductace for the precise torque control owing to the reluctance torque. This paper presents two method to measure the each-axis inductance. The first method uses the peak current that is measured by applying the pulsewise voltage on the each position of IPMSM. The second uses the hysteresis loop of the flux and current measured by applying the positive and negative pulsewise voltage alternately on the each-axis.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.14 no.3
• /
• pp.81-87
• /
• 2006

In this paper, the belt-pulley mechanical loss is investigated. A bondgraph model for the mechanical loss is developed from the viewpoint of the power flow by assuming that all power losses are attributed to the torque loss. The mechanical loss model consists of transient and steady state part. The coefficients of the power loss model are obtained from the experiments. It is found from the simulations and experiments that the steady state loss depends on the line pressure, input torque and rotational speed while the transient loss depends on the rotational speed, shift speed and the inertial torque.