• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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• pp.25-28
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• 1989

This paper is to study a modified hysteresis band current control technique for keeping the fixed switching frequency. The control technique is applied to an brushless DC motor(BLDCM). This paper gives an analysis of the modified hysteresis band with isolated neutral case and the PI controller with current limiter in forward loop; their characteristics are studied by simulation. The proposed control technique is implemented by using a microprocessor-based system.

• 대한전기학회논문지
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• 제34권7호
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• pp.283-288
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• 1985

This paper is concerned with the analysis of microprocessor-based PID control for the current source inverter-induction motor derive system. A linearized dynamic model of the motor is derived and is converted into the discrete-time model. With the equation, the overall system including the feedback loops is formulated into a single discrete-time state equation. The stability regions are determined at various values of controller gains. The transient responses of the motor speed are simulated by digital computer and are verified by laboratory experiments.

• 한국산학기술학회논문지
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• 제8권6호
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• pp.1388-1393
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• 2007

본 논문에서는 물리, 화학, 생물 등 실험 교과목에 대하여 학생들이 가정 및 여러 장소에서 원격 접근 기능을 가지는 마이크로프로세서 기반 실험 장치(Microprocessor Based Laboratory Systems, MBL)의 소프트웨어 및 하드웨어 플랫폼 구조 설계에 관하여 연구하였다. 본 시스템에서는 학교 실험실에서 수행되는 실험교과목에 대한 다양한 주변 환경 및 실험방법에 대하여 지원 가능하도록 원격접근기능을 TCP/IP 프로토콜로 구현한 NUTOS를 실시간 운영체제를 사용하였다. 본 논문에서 제안한 MBL-NUTOS(Microprocessor Based Laboratory-NUT/OS)는 실시간 인터넷 접속이 가능하며 서버 또는 클라이언트로 활용 가능하도록 설계되었으며 실험을 통하여 본 플랫폼의 유용성을 입증하였다. 본 MBL 하드웨어 플랫폼에서는 기존의 마이크로프로세서 기반 실험 장치가 가지고 있지 않은 네트워크 접근기능이 구현되었으며 또한 실시간으로 실험 상황을 인터넷으로 억세스 할 수 있는 장점을 가지고 있다. 더욱이, 저비용 고집적도를 가지게 설계되어 일선 학교에서 용이하게 사용 할 수 있도록 하였으며, 학교 실험실에서 수행되는 실험이 미래 유비쿼터스 교육환경에 적용 가능하도록 하여 첨단 과학에 대한 학생들의 인지를 넓히는 주요 매개체로서 그 교육 효과를 높이도록 하였다.

• 대한전기학회논문지
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• 제35권12호
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• pp.541-554
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• 1986

This paper presents the results of driving performance analysis of permanent magnet synchronous motor using a microprocessor based control system. The system consists of three phase power transistor inverters, three phase controlled rectifier, three central processing units, and sensors. The three CPUs are, respectively, used to generate PWM control signals for the inverter generating three phase sine wave, to generate the gate control signals for firing the converter, and to supervise other two CPUs. The supervisor is used to compute PI control algtorithm to three phase reference sine wave for the inverter. It is also used to maintain a constant voltage frequency ratio for the converter operating as a constant torque controller. The inverter CPU retrieves precomputed PWM patterns from look up tables because of computation speed limitations found in almost available microprocessors. The converter CPU also retrieves precomputed gate control patterns from another look-up tables. For protecting the control ststem from any damage by extraordinary over currents, the supervisor receives the data from current sensor, CT, and break down the CB to isolate the circuits from source. A resolver has a good performance characteristics of overall speed range, especially on low speed range. Therefor the speed control accuracy is impoved. The microprocessor based PM synchronous motor control system, thus, has many advantages such as constant torque characteristics, improvement of wave, limitation on extraordinary over currents, improvement of speed control accuracy, and fast response speed control using multi-CPU and look-up tables.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.195-198
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• 2008

최근 태양광 발전시스템 등 낮은 전압을 발생하는 전원소스를 이용하여 높은 승압효과를 얻기 위한 멀티레벨 인버터에 대한 관심이 높아지고 있다. 본 논문은 FPGA 기반 멀티레벨 인버터용 스위칭 함수를 구현하고자 한다. FPGA는 프로그램 가능한 로직 디바이스로써 풀 디지털 스위칭함수를 구현하는 효율적이다. 본 논문에서는 FPGA 기반 스위칭 함수를 구현하기 위해서 마이크로프로세서로부터 출력되는 클럭과 동기신호로 독립적으로 구동이 되도록 하였다.

• 전자공학회논문지SC
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• 제40권6호
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• pp.31-38
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• 2003

단열회로를 이용한 16-bit 저전력 마이크로프로세서를 설계하였다. 본 논문에서 설계한 마이크로프로세서는 콘트롤 블록, 멀티포트 레지스터 파일, 프로그램 카운터 그리고 ALU로 구성되어 있다. 또한 저전력 단열 프로세서에 필요한 효율적인 4-phase 전원클럭 발생기도 설계하였다. 단열회로는 ECRL(Efficient Charge Recovery Logic)을 기반으로 설계되었고 0.35㎛ CMOS 공정을 이용하여 구현하였다. 단열프로세서와 일반적인 프로세서와 에너지를 비교하기 위해서 CMOS를 기반으로 한 프로세서를 설계하여 에너지 비교를 수행하였다. 시뮬레이션 결과 기존의 CMOS 프로세서보다 2.9∼3.1배의 에너지 감소효과를 보였다.

• 대한임베디드공학회논문지
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• 제12권2호
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• pp.89-96
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• 2017

We develop an embedded system to measure various sensor data, control multiple motors, and communicate with mobile devices for system managements. Choosing TI AM3359 microprocessor featuring high processing performance, low power consumption, and various I/O device support, we design and build the embedded system hardware so that it supports multiple global positioning system (GPS) and gyro sensor modules to measure precise position; multiple pulse width modulation (PWM) outputs to control multiple direct current (DC) motors; a Bluetooth module to communicate with mobile devices. Then, we port the boot loader and device drivers to the built circuit board and construct the firmware development environment for the application programming. The performance of the designed and implemented embedded system is demonstrated by real motor control test using GPS and gyro sensor data and control parameters configured by a mobile device.

• Journal of Advanced Marine Engineering and Technology
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• 제28권6호
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• pp.916-921
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• 2004

This paper describes microprocessor-based control of photovoltaic power conditioning system. where the microprocessor is responsible for control of output power in accordance with the generated array DC power. The microprocessor includes the control algorithm of maximum power point tracking and converter control algorithm. In this power, we have designed a MPPT(Maximum Power Point Tracker) algorithm with environment factors and a PWM(Pulse Width Modulation) algorithm for high efficiency. The controller has been tested in the laboratory with the power conditioner and shows excellent performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.492-495
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• 1991

This paper proposes the microprocessor-based step-up chopper system used for the battery charge from the photovoltaic arrays. The proposed scheme tracks the maximum power point by analyzing the voltage and power phasors which vary as the solar irradiation quantity. In this system, protection for the overcharge and overdischarge in also provided.

• 전기학회논문지P
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• 제62권3호
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• pp.133-138
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• 2013

A large generator is an important role in transferring an electric power to power system. The IEDs of large generator often use microprocessor technology to obtain a digital relay system with a wide range of measuring, protection, control, monitoring, and communication functions. However, all generator protection and control systems in Korea imported from abroad and are being operated. In order to reduce the large expense and improve the reliable operation, development of generator protection and control system by domestic technology is required. This paper deals with the design of the IED of generator protection panel for development of generator protection and control system. The major emphasis of the paper will be on the description of hardware and signal processing test results and measurement accuracy of the prototype IED. By developing of generator IED based on DSP and microprocessor, replacement of the generator protection panel imports are expected to be effective.