• Proceedings of the KIPE Conference
• /
• 1998.07a
• /
• pp.342-346
• /
• 1998

The brushless DC motor with trapezoidal back emfs has torque ripple due to phase commutation. The torque ripple generates noise and vibration and cause errors in position control so this makes the brushless DC motor less suitable for high performance servo applications. In this paper, we propose a new current control method to reduce the torque ripple due to commutation, when the unipolar PWM method is applied for the phase current control of brushless DC motor.

• Proceedings of the KIEE Conference
• /
• 1988.11a
• /
• pp.53-55
• /
• 1988

The application of Sliding Mode Control for inproving the dynamic response of a Multi-Phase-Bipolar (MPB) Brushless DC motor based position Brushless DC motor system is presented. Sliding Mode Control gives fast dynamic response with no overshoot and zero steady state error. It has the important feature of bins highly robust. A design procedure is outlined for the Sliding Mode Controller for a MPB Brushless DC motor. Digital computer simulation of the overall position control system is carried out using a time domain model in the d-q reference frame.

• The Transactions of the Korean Institute of Electrical Engineers B
• /
• v.48 no.3
• /
• pp.131-138
• /
• 1999

Generally, the digital controller has many advantages such as high precision, robustness to electrical noise, capability of flexible programming and fast response to the load variation. In this study, we have established proper mathematical equivalent model of Brushless DC (BLDC) motor and estimated the motor parameter by means of the back-emf measurement as being the step input to the controlled target BLDC motor. And the validity of proposed estimation method is confirmed by the test result of step response. As well, we have designed the reasonable digital controller as a consequence of the root locus method which is obtained from the open-loop transfer function of BLDC motor with hall sensor, and the determination of control gain for variable speed control. Here, revised Ziegler-Nichols tuning method is applied for the proper digital gain establishment, and the system stability is verified by the frequency domain analysis with Bode-plot and experimentation.

• 제어로봇시스템학회:학술대회논문집
• /
• 1990.10a
• /
• pp.122-126
• /
• 1990

This paper discusses the possibility of applying fuzzy logic controller in a microprocessor-based brushless DC servo motor controller, which requires faster and more accurate response compared with other industrial processes. Limitations of fuzzy logic controller are also described.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.207-210
• /
• 1998

Brushless servomotor systems offer a great advantae in unmanned factories where a great number of servomotors are employed, because of its easy maintenance charateristics and controllability. This paper propose a sinusoidal type brushless DC motor speed servo system which has high efficiency and usability in industrial field as described above. And this servo system is realized by a new Auto-Tuning PI control algorithm and verified it's practical potential of implementation by self-designed driver system. In particular, DSP(digital signal processor) is adopted in this study as controller and sensor signal processor owing to their fast computational capability and suitable architecture.

• 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.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.1
• /
• pp.21-26
• /
• 2000

This paper describes a positioning system for ultra-precision that will be utilized in semiconductor manufacturing field and precision machinery. This system is composed with laser scale unit with 10nm resolution, ball screw with LM guide, brushless DC servo motor, vibration isolator and is equipped in chamber for continuous measuring environment. The dynamic of table, the problem of servo control and the traceability for micro step motion are described. These data will be applied for getting more stable system with 50nm resolution.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.43 no.6
• /
• pp.982-990
• /
• 1994

In this paper, we consider feedback-kinearizing control of brushless dc motors which have been increasingly used in high-performance servo applications, We completely characterize the whole class of the feedback controllers that enable the brushless dc motors to behave like linear systems but without torque ripple. The whole class of the feedback-linearizing controllers is characterized in the explicit form which contains a function to be chosen freely. The previously known controllers correspond to either the particular ones in our whole class of the feedback-Linearzing controllers or their truncated Fourier expansions. This free function can be used to achieve other control objectives as well as linear dynamic characteristics. Furthermore, our feedback-linearizing controllers can be easily determined from the measurement data of back EMF.

• Proceedings of the KIEE Conference
• /
• 2003.04a
• /
• pp.170-172
• /
• 2003

Among low power servo applications, classical DC motors are very popular because they are reasonably cheap and easy to control. The main disadvantage is the mechanical collector which has only a limited life period. Also, brush sparking can destroy the rotor coil, generate EMC problems. So permanent magnet brushless do motors and drives are being used increasingly in a wide range of applications. This has been made possible with the advantages of high performance permanent magnets with high coercively and residual magnetic, which make it possible for the PM to have superior power density, torque to inertia ratio and efficiency, when compared to an induction or conventional dc machine. This paper presents the design of a PM brushless dc motor drive simplistically operates as a classical dc motor. The BLDC motor drive system for this paper composes to the power integrated circuits, the one chip device. And several simple semiconductors add to drive system for a motor drive system simplistically operates as a conventional dc motor. Test results confirmed the feasibility of the proposed motor drive system design.

• Journal of the Korean Institute of Telematics and Electronics T
• /
• v.36T no.1
• /
• pp.41-50
• /
• 1999

The brushless DC motor is widely being used in unmanned factories for its easy maintenance and characteristics of controllability. In this paper, we designed a speed control servo system of a sinusoidal type bmshless DC motor which has high efficiency and usefulness in the industrial fields. This servo system is realized by a controller which is required for driving motors and a new auto-tuning PI control algorithm. The DSP(Digita1 Signal Processor) is adopted as a main controller and a sensor signal processor owing to its fast computational capability and suitable architecture. Also, the hardware PWnl(Pulse Width Modulation) current controller is implemented to pursue a speed command exactly. By experimental results, it is verified that the speed response is pursued fast after command value and the steady-state response is well converged for command value variation without overshoots.