• Proceedings of the KIEE Conference
• /
• 1989.11a
• /
• pp.258-263
• /
• 1989

The configuration of Brushless DC moter is similar to the permanent magnet Synchronous moter. Power transistors are oftenly used to supply the switching by feedback signals of rotor positioning sensors. Brushless DC moter have been used in Aerospace and Robotics where the electromagnetic noise or the sparking of the commutator contact can not be tolerated and long - lived maintenance - free operation is required. This paper describes the design of the microprocessor - based controller for the Brushless DC moter. The controller is designed to operate for the constant torque generation and variable speed control using sinusoidal PWM inverters and resolvers as rotor positioning sensors.

• Proceedings of the Korean Society of Marine Engineers Conference
• /
• 2006.06a
• /
• pp.77-78
• /
• 2006

A mixed method between $H_2\;and\;H_{\infty}$ control are widely applied to systems which has parameter perturbation and uncertain model to obtain an optimal robust controller. Brushless Direct Current (BLDC) motors are widely used for high performance control applications. Conventional PID controller only provides satisfactory performance for set-point regulation. However, with the presence of nonlinearities, uncertainties and perturbations in the system, conventional PID is not sufficient to achieve an optimal robust controller. This paper presents an approach to ease designing a Mixed $H_2/H_{\infty}$ PID controller for controlling speed of Brushless DC motors and the genetic algorithm is used to solve the optimized problems. Numerical results are shown to prove that the performance in the proposed controller is better than that in the optimal PID controller using LQR approach.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.9 no.2
• /
• pp.126-133
• /
• 2004

In this paper, a new current control algorithm is proposed for four-switch three-phase brushless DC(BLDC) motor drives, which are suitable for low cost applications. A current reference generation scheme is developed and implemented to obtain high performance characteristics in the four-switch system, such as small torque ripple and fast dynamic speed/torque response. Especially, the proposed scheme can successfully reduce the torque ripple during commutations, so that it can be expected that the four-switch system can be much more practically applied for the industrial application areas.

• Proceedings of the KIEE Conference
• /
• 1997.07a
• /
• pp.171-173
• /
• 1997

This paper presents analysis of the radial force density in brushless DC motor of which distribution is not uniform in the axial direction. The analysis considering 3D shape of teeth and overhang is not only important but essential to calculate the radial force density that acts on the teeth of stator, because it is frequent source of vibration and changes at the end of teeth. For the analysis, a new 3D equivalent magnetic circuit network method taking into account movement of the rotor without remesh is proposed. The radial force density is calculated by Maxwell stress tensor and analyzed by discrete Fourier transform.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.2 no.3
• /
• pp.44-50
• /
• 1997

This paper describes an indirect sensing method for the rotor flux position of interior permanent magnet (IPM) brushless DC motors. The phase inductances of an IPM motor vary appreciably according to the rotor position. The waveform characteristics of the terminal voltage of IPM brushless DC motors is analysed and a simple and practical method for indirect sensing of the rotor position is proposed. A compact and economical sensorless drive is implemented and tested using a 87c196mc 16-bit one-chip microprocessor. The experimental results show the validity of the proposed method. The drive is applied to drive a compressor of air-conditioner and works well from 1,200 to 6,600 [rpm].

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.10
• /
• pp.1038-1044
• /
• 2009

In this study, vibrations of an electric motor are analyzed when the motor has the interaction between mechanical and electromagnetic behaviors. For this vibration analysis a 3-phase 8-pole brushless DC motor is selected. Vibrations of the motor are influenced by coupled electromechanical characteristics. The variation of air-gap induced by vibration has an influence on the inductance of the motor coil. To analyze dynamic characteristics of the rotor, we studied inductance by the variation of an air-gap. After obtaining the kinetic, potential and magnetic energies for the motor, the equations of motion are derived by using Lagrange's equation. By applying the Newmark time integration method to the equations, the dynamic responses for the displacements and currents are computed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2001.11a
• /
• pp.465-470
• /
• 2001

Two-phase BLDC(brushless DC) motor has larger torque ripple than three-phase BLDC motor because of its unique skeleton-type structure. An electronic switching mechanism to change the current-direction of the BLDC motor can be a source of vibration as well as unbalanced rotor weight. A proper switching timing which makes less vibrations was considered by changing the position of sensing element around the center of rotation. Also, the current of the motor was measured for the calculation of the motor efficiency. From the vibration test results and with the consideration of the motor efficiency, an optimal switching position of the Hall sensor was found.

• Journal of the Korea Safety Management & Science
• /
• v.17 no.4
• /
• pp.403-410
• /
• 2015

This study documents the 3-phase BLDC(Brushless DC) motor to improve conventional exhaust fan motor. Energy efficiency, noise, and air pollution reduction for the high-performance vibration of the BLDC motor has been used in many fields. It is necessary to achieve the information of rotor position for driving 3-phase type brushless DC motor. It is also necessary that the PWM control algorithm design for a MOSFET driver to control the motor speed control for each of three phases. BLDC motors for exhaust fan, we studied the controller and software. The control circuit and motor control program through which Exhaust fan up close and person can be used safely and protect the environment.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.4
• /
• pp.603-609
• /
• 2008

Slotless linear brushless DC motor are widely used in precision machine applications because of their advantages such as low of detent force, negligible iron loss. But they have a disadvantage such as low thrust density, thrust ripple, and excessive use of permanent magnet materials. These lead to undesirable performance and high production cost. In this paper, we deal with the design and characteristics investigation of a air-core tubular linear brushless DC(TLBLDC) motor with air-core stator and permanent magnet mover. And to investigate the static and dynamic characteristics of air-core TLBLDC motor, the prototype machine is manufactured and analyzed by F.E.M. and Matlab simulink simulations. Especially, dynamic characteristics of air-core TLBLDC motor driven with 6 step inverter are simulated by F.E.M.coupling with external circuit and Matlab simulink program, and measured for the prototype motor. The simulation results are compared to the experimental results such as current waves, thrust and speed curve.

• Proceedings of the IEEK Conference
• /
• 2001.06e
• /
• pp.143-146
• /
• 2001

Servomotors, especially linear brushless servomotors have numerous advantages over ball screws, timing belts, rack/pinion drives and friction drives compared wi th rotary servomotors This paper proposes an linear regression method as the estimated ion of unknown parameters from the linear brushless DC motor The estimated parameters are used to tune the gain of controller. In order to agree with this purpose, Digital Signal Processor (TMS320F240), developed for implementation of the motor control, is adopted in this study. The processor playing an important role in controller has A/D converters, PWM generators, riched I/O ports internally.