• 반도체디스플레이기술학회지
• /
• 제23권1호
• /
• pp.48-51
• /
• 2024

Recently, high-performance BLDC(Brushless DC) motors are being applied to various fields such as industrial and personal mobility devices and drones. To achieve the best performance of BLDC, sensors such as hall sensors, encoders, and resolvers are used to determine the position of the rotor, and various speed control technologies are being developed. However, due to problems with high-speed control due to external environmental factors and frequency bandwidth of semiconductor sensing devices, research on BLDC motors without semiconductor sensing devices is in progress. Therefore, in this study, a signal brush was added to the end of the rotor of a BLDC motor and the rotor position of the BLDC motor was detected by analyzing the signal output through the signal brush.

• Journal of Power Electronics
• /
• 제16권1호
• /
• pp.227-237
• /
• 2016

A novel digital current control strategy for digitally controlled DC-DC switching converters, referred to as Adjacent Cycle Sampling (ACS), is proposed in this paper. For the ACS current control strategy, the available time interval from sampling the current to updating the duty ratio, is approximately one switching cycle. In addition, it is independent of the duty ratio. As a result, the contradiction between the processing speed of the hardware and the transient response speed can be effectively relaxed by using the ACS current control strategy. For digitally controlled buck DC-DC switching converters with trailing-edge modulation, digital current control algorithms with the ACS control strategy are derived for three different control objectives. These objectives are the valley, average, and peak inductor currents. In addition, the sub-harmonic oscillations of the above current control algorithms are analyzed and eliminated by using the digital slope compensation (DSC) method. Experimental results based on a FPGA are given, which verify the theoretical analysis results very well. It can be concluded that the ACS control has a faster transient response speed than the time delay control, and that its requirements for hardware processing speed can be reduced when compared with the deadbeat control. Therefore, it promises to be one of the key technologies for high-frequency DC-DC switching converters.

• Journal of Electrical Engineering and Technology
• /
• 제1권3호
• /
• pp.279-286
• /
• 2006

A method for estimating the instantaneous phasor of a fault current signal is proposed for high-speed distance protection that is immune to a DC-offset. The method uses a modified notch filter in order to eliminate the power frequency component from the fault current signal. Since the output of the modified notch filter is the delayed DC-offset, delay compensation results in the same waveform as the original DC-offset. Subtracting the obtained DC-offset from the fault current signal yields a sinusoidal waveform, which becomes the real part of the instantaneous phasor. The imaginary part of the instantaneous phasor is based on the first difference of the fault current signal. Since a DC-offset also appears in the first difference, the DC-offset is removed trom the first difference using the results of the delay compensation. The performance of the proposed method was evaluated for a-phase to ground faults on a 345kV 100km overhead transmission line. The Electromagnetic Transient Program was utilized to generate fault current signals for different fault locations and fault inception angles. The performance evaluation showed that the proposed method can estimate the instantaneous phasor of a fault current signal with high speed and high accuracy.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2015년도 전력전자학술대회 논문집
• /
• pp.415-416
• /
• 2015

This paper deal with a CRM control method of DC-DC converter of increase its performance. It allows high speed switching in critical current region when driving converter to improve efficiency of converter. The validity of the theory is verified by the comparison of the simulation results proposed between method and conventional method.

• 디지털콘텐츠학회 논문지
• /
• 제18권6호
• /
• pp.1193-1198
• /
• 2017

본 논문에서 개발된 IGBT 구조는 DC 송배전을 위한 고전력 스위치 반도체로서 사용되며, 빠른 스위칭 속도 및 개선된 항복전압 특성을 확보하여, 향후 신재생 장거리 DC 송전을 위한 중요한 전자 소자로서 이용될 것이 기대되고 있다. 새로운 타입의 차세대 전력 반도체로서, 스위칭 속도를 향상시키면서 동시에 항복 전압의 특성을 개선시켜, 전력 손실 특성을 줄이도록 설계되었고, 높은 전류 밀도의 장점을 동시에 획득 가능하다. 이러한 개선된 특성은 Planar IGBT의 N-drift 영역에 $SiO_2$를 추가로 도입함으로서 얻어지며, Sentaurus TCAD 시뮬레이션 툴을 사용하여, 비교 분석하였다.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회A
• /
• pp.1138-1142
• /
• 2007

As a brush DC motor, the brushless DC motor is also operated by DC power supply but has no mechanical contacts occurred by a brush or a commutator. Though the performance of BLDC motor is almost similar with that of DC motor, the BLDC motor has the advantage of the high speed responsibility, the high controllability, and the high effectiveness. The control valve using the BLDC motor, which excludes the burnout effect provoked possibly by the vacuum condition during the flight, is employed for the upper stage of a launch vehicle. For the component level analysis, the dynamic response characteristics of BLDC and DC motors to the same design input sources have been studied in using AMEsim.

• 한국기계가공학회지
• /
• 제2권4호
• /
• pp.88-94
• /
• 2003

The DC motor has the strong characteristics in the speed response, the system parameter variations and the external influence and is used as the speed controller with its good starting torque in the distributing industry. However development of the Microprocessor which is for high speed switching program can make better control system. This paper introduce to design of the high-effective DC motor controller that is using Software Bang-Bang Program of Fuzzy algorithm and to verity a PI controller and a Fuzzy controller.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
• /
• pp.138-138
• /
• 2000

In this paper, a methodology for designing a controller based on inverse dynamics for speed control of DC motors is presented. The proposed controller consists of a prefilter, the inverse dynamic model of a system and a fuzzy logic controller. The prefilter prevents high frequency effects from the inverse dynamic model. The model of the system is characterized by a nonlinear equation with coulomb friction. The fuzzy logic controller regulates the error between the set-point and the system output which may be caused by disturbances and it simultaneously traces the change o( the reference input. The parameters of the model are estimated by a genetic a]gorithm. An experimental work on a DC motor system is carried out to illustrate the performance of the proposed controller

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
• /
• pp.623-628
• /
• 2009

There is an increasing demand for efficient high power/weight auxiliary power supplies for use on high speed traction application. Many new conversion techniques have been proposed to reduce the voltage and current stress of switching components, and the switching losses in the traditional pulse width modulation(PWM) converter. Especially, the phase shift full bridge zero voltage switching PWM techniques are thought most desirable for many applications because this topology permits all switching devices to operate under zero voltage switching(ZVS) by using circuit parasitic components such as leakage inductance of high frequency transformer and power device junction capacitance. The proposed topology is found to have higher efficiency than conventional soft-switching converter. Also it is easily applicable to phase shift full bridge converter by applying an energy recovery snubber consisted of fast recovery diodes and capacitors.

• 한국자동차공학회논문집
• /
• 제6권4호
• /
• pp.39-46
• /
• 1998

For permanent magnet brushless DC motors used for high speed fuel pumps, torque ripple is an important origin of vibration, acoustic noise and speed fluctuation. In this paper, the output torque profile of a PM motor with one phase energized is decomposed into the commutation torque, the reluctance torque and the armature reaction torque according to their source origins. It verifies that the output torque profile is qualitatively equivalent to the BEMF profile for low reluctance motors. This paper discusses the effect of magnet pole shaping and magnet arc length on the output torque and torque ripple. A magnet edge shaping is proposed to design a trapezoidal BEMF motor without torque ripple, with minimal sacrifice of the maximum output torque.