• Journal of the Korean Society for Precision Engineering
• /
• v.27 no.6
• /
• pp.39-46
• /
• 2010

Linear induction motor is adopted as an actuator of the planar stage. An inherently poor characteristic at zero or ultra-low speed zone of the induction motor is remarkably improved due to a recent development of power electronic semiconductor technology and a spatial vector control theory. At present, a servo response speed of the induction motor reaches 90 percent of one of PM synchronous or BLDC motor. Specially, as a secondary of the induction motor can be constructed using uniform conducting sheets, there is no periodic force ripple as in PM motors. So, the induction motor can be superior to another driving means under a certain condition. This paper discusses the overall development procedure of non-contact planar stage with a big workspace using linear induction motors.

• Proceedings of the KIEE Conference
• /
• 2000.11b
• /
• pp.229-231
• /
• 2000

Precision control technologies are required for Lithography devices. The Linear BLDC Motor is used for operations of the stage. The stage is installed in Lithography devices. The stage is basically controlled though three directions (x, y, z axes). This paper presents precision control technologies of the Linear BLDC Motor (only one axes) by using computer simulations. We will plan that real systems is made and tested.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1017-1018
• /
• 2011

This paper deals with a magnetic field analysis on brushless DC(BLDC) motor with radial magnetization permanent magnet. In order to analyze the magnetic field, multi-layer analysis based on space harmonics method is employed. Finally, the analytical results are validated by non-linear Finite Element Analysis(FEA).

• Journal of Power Electronics
• /
• v.3 no.1
• /
• pp.10-16
• /
• 2003

Implementation and experimental verification of a simple neuro-controller (SNC) as a speed controller for a brush less DC (BLDC) motor is presented. The SNC with one weight and a linear hard limit activation function is trained on-line using the back propagation algorithm. A modified error function is used to ensure good performance during the on-line training, which has been used without previous off-line training. The SNC has been implemented using a computer-interface card mounted on a PC. The driving system performance has been investigated by a number of experimental tests for a variety of input reference speed trajectories.

• Proceedings of the IEEK Conference
• /
• 1999.06a
• /
• pp.1121-1124
• /
• 1999

Linear motor is able to produce line movement without rotary-to-line converter at the system required line moving. Thus Linear motor has no gear, screw, belt for line movement. Therefore it has some advantage which decrease friction loss, noise, vibration, maintenance effort and prevent decay of control performance due to backlash. This paper proposes the estimation method of unknown parameters from the BLDC Linear motor and determine the PI controller gain through this estimation. Each control movement that is current, speed, position control, and PWM wave generation is performed on Processor, which is DSP(Digital Signal Processor), having high speed performance. PI theory is adopted to each for controller for control behavior More fast convergence to command position is accomplished by applying the new velocity locus which derived from position error.

• Proceedings of the KIEE Conference
• /
• 2001.07d
• /
• pp.2399-2401
• /
• 2001

This Paper presents a positioning control method of the LBLDCM(Linear Brushless DC Motor) under friction. The friction may cause steady state position error. So it is necessary to consider friction effect for precision positioning control. The proposed control method uses disturbance observer algorithm and friction compensation. The experimental results of the proposed control method based on the disturbance observer are presented to show its effectiveness.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• v.9 no.1
• /
• pp.959-962
• /
• 2005

Servomotors are used as key components of automated system by performing accurate positioning, accurate speed regulation, and precise motion control in response to commands from computers and sensors. Especially linear brushless servomotors have numerous advantages over ball screws, timing belts, rack/pinion drives and friction drives compared with rotary servomotors. This paper proposes the estimation of unknown parameters from the linear brushless DC motor which is operated by sinusoidal commutation. The estimated parameters are used to tune the controller gain and disturbance observer. In order to agree with this purpose, Digital Signal Processor(TMS320F240), developed for implementation of a speed Field Oriented Control(FOC), adopted in this study. The processor playing an important role in controller has A/D converters, PWM generators, riched I/O port internally.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.61 no.2
• /
• pp.298-302
• /
• 2012

The linear encoder used in the BLAC driving circuit consists usually analog type sensor, and need signal transform from analog sinusoidal to digital one for application in the PWM algorithm that is used to control motor current. When the motor is driven in low speed, it is required many operations and higher quality DSP to convert the hole sensor signal to digital one with enough resolution. In this paper, the another method to convert that signal with enough resolution without calculation of sine function is proposed. This is very simple and have high resolution even if the motor is driving in low speed. To verify the proposed method, BLAC motor is used, and it is proved that the motor is tracking well the reference step signal in the low speed as well as in the high one.

• Proceedings of the KIEE Conference
• /
• 2003.04a
• /
• pp.9-12
• /
• 2003

Brushless do motors have been replacing brush type motors in machine tool and robotics applications over the last number of years This Paper deals with the design and application of the slot-less permanent magnet synchronous motor (PMSM). The slot-less PMSM eliminates rotational cogging torque due to permanent magnet preferred positions decreases core loss and thus increases efficiency, provides excellent torque-to-volume and power-to-volume ratios, and has a linear current versus torque relation. The PMSM with slot-less stator is designed and manufactured, which will be used for high speed and high efficiency application such a medical instruments.

• Proceedings of the KIPE Conference
• /
• 2001.07a
• /
• pp.25-29
• /
• 2001

The BLDCM (Brushless DC Motor) characterized by linear torque to current, and speed to voltage has low acoustic noise, and fast dynamic response. Moreover, it has high power density with high proportion of torque to inertia in spite of small size drive. But, it produce torque ripple due to the motor inductance components in stator windings and back-EMF, when armature current is commutated. Therefore, it is difficult to apply the BLDCM to a precision servo drive system. In this paper is proposed to a new current control algorithm with using fourier series coefficients can minimize torque ripple due to the phase current commutation of BLDCM. Simulation and Experimental results prove the effectiveness the proposed algorithm through comparison with the conventional used unipolar PWM method.