• Journal of information and communication convergence engineering
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• 제11권1호
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• pp.56-61
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• 2013

Modern integrated circuits (ICs) are becoming an integrated parts of analog, digital, and radio frequency (RF) circuits. Testing these RF circuits on a chip is an important task, not only for fabrication quality control but also for tuning RF circuit elements to fit multi-standard wireless systems. In this paper, RF test circuits suitable for embedded testing are introduced: RF power detectors, power control circuits, directional couplers, and six-port reflectometers. Various types of embedded RF power detectors are reviewed. The conventional approach and our approach for the RF power control circuits are compared. Also, embedded tunable active directional couplers are presented. Then, six-port reflectometers for embedded RF testing are introduced including a 77-GHz six-port reflectometer circuit in a 130 nm process. This circuit demonstrates successful calibrated reflection coefficient simulation results for 37 well distributed samples in a Smith chart. The details including the theory, calibration, circuit design techniques, and simulations of the 77-GHz six-port reflectometer are presented in this paper.

• Journal of Power Electronics
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• 제16권5호
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• pp.1678-1688
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• 2016

This paper presents a capacitive power transfer (CPT) system using a Class-E resonant inverter. A Class-E resonant inverter is chosen because of its ability to perform DC-to-AC inversion efficiently while significantly reducing switching losses. The proposed CPT system consists of an efficient Class-E resonant inverter and capacitive coupling formed by two flat rectangular transmitter and receiver plates. To understand CPT behavior, we study the effects of various coupling distances on output power performance. The proposed design is verified through lab experiments with a nominal operating frequency of 1 MHz and 0.25 mm coupling gap. An efficiency of 96.3% is achieved. A simple frequency tracking unit is also proposed to tune the operating frequency in response to changes in the coupling gap. With this resonant frequency tracking unit, the efficiency of the proposed CPT system can be maintained within 96.3%-91% for the coupling gap range of 0.25-2 mm.

• 한국정보통신학회논문지
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• 제18권6호
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• pp.1413-1421
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• 2014

본 논문은 마스터로 동작하는 32 비트 RISC 프로세서와 전력을 제어할 수 있는 다수의 슬레이브가 동기되어 동작하는 전력 제어 임베디드 시스템을 구현하였다. Core-A 플랫폼은 Core-A 프로세서, AMBA 버스, SSRAM, AC97, DMA, UART, GPIO모듈 등으로 구성된다. 슬레이브는 4 비트의 디지털 데이터의 값에 비례하여 220V 전력을 제어할 수 있는 아날로그 회로와 마스터가 보내는 신호에 동기되어 다양한 전력제어 패턴을 생성하는 제어 시스템을 설계 하였다. Core-A 플랫폼이 라이브러리로 구축된 Flowrian II를 사용하여 소프트웨어를 크로스 컴파일하고 하드웨어 회로를 시뮬레이션으로 검증하였다. 임베디드 시스템은 FPGA 검증 보드와 CPLD 칩에 구현되었고 전력제어 아날로그 보드를 제작하여 구현하였다.

• Journal of Electrical Engineering and Technology
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• 제9권5호
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• pp.1454-1470
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• 2014

This paper propose a new power conditioner topology with intelligent power management controller that integrates multiple renewable energy sources such as solar energy, wind energy and fuel cell energy with battery backup to make best use of their operating characteristics and obtain better reliability than that could be obtained by single renewable energy based power supply. The proposed embedded controller is programmed for maintaining a constant voltage at PCC, maximum power point tracking for solar PV panel and WTG and power flow control by regulating the reference currents of the controller on instantaneous basis based on the power delivered by the sources and load demand. Instantaneous variation in reference currents of the controller enhances the controller response as it accommodates the effect of continuously varying solar insolation and wind speed in the power management. The power conditioner uses a battery bank with embedded controller based online SOC estimation and battery charging system to suitably sink or source the input power based on the load demand. The simulation results of the proposed power management system for a standalone solar/WTG/fuel cell fed hybrid power supply with real time solar radiation and wind velocity data collected from solar centre, KEC for a sporadically varying load demand is presented in this paper and the results are encouraging in reliability and stability perspective.

• 전기전자학회논문지
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• 제18권2호
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• pp.282-290
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• 2014

본 논문은 1인승 전기차량의 임베디드 전동 제어장치 설계를 제안하였다. 제안된 임베디드 장치는 PIC18F8720 프로세서, 16Mb flash ROM, 32Mb SDRAM과 신호처리회로로 설계되었다. 제안된 1인승 전기차량은 4KW 인휠 BLDCM, $180^{\circ}$ 도통 공간 벡터제어 3상 전압형 인버터, PID 속도제어기와 전동제어 장치와 임베디드 제어장치로 구성된다. 이 1인승 전기차량은 역 3륜 형태의 기계적인 구조를 가지고 있으며, 인휠 BLDCM과 틸팅 기능을 가지는 조향 메카니즘이 적용되었다. 또한 제안된 임베디드 전동제어장치의 성능은 PEV에 대한 Lab 실험과 도로 주행시험을 통하여 검증하였다.

• 한국융합학회논문지
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• 제10권12호
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• pp.1-6
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• 2019

본 논문에서는 IPTV와 셋톱박스의 전원 동기화를 통한 전력 손실을 줄이는 알고리즘을 연구하였다. 그리고 임베디드 보드에서 Android 7.0으로 IPTV (Miracast 및 인터넷)를 제어 할 수 있는 안드로이드 시작프로그램을 설계하였다. 시작 프로그램은 IPTV의 원격 제어로 제어 할 수 있다. 그리고 IPTV를 사용할 때 TV를 수신할 수 있으며, Miracast 및 Embedded 보드는 절전 모드로 전환된다. 이러한 방식으로 한 모드를 선택하면 다른 두 모드가 절전 모드로 전환되고 절전 제어 기술이 적용되어 에너지 소비를 줄일 수 있었다. 이 논문에서 사용 된 보드는 Android 버전 7.1.2 버전의 Raspberry pie 3B / B + 및 Asus Tinker 보드이며, Android Studio 프로그램을 사용하여 안드로이드 시작 프로그램을 작성 하였다. 동기화 제어 알고리즘은 IPTV 원격 제어와 함께 작동하도록 개발 되었다. 이러한 방식으로 개발 된 절전 제어 기술 및 원격 제어 동기화 제어 알고리즘은 Android 시작 프로그램에서 리모컨으로 IPTV, Miracast 및 인터넷 선택 및 작동이 정상적인 것을 확인할 수 있었다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권3호
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• pp.180-187
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• 2004

A conventional power supply of a microwave oven has a 60Hz transformer and high voltage capacitor(HVC). Though it is very simple and has low cost, it has several problems such as large size, heavy weight and low efficiency To improve these problems, various high frequency inverter type power supply have been investigated and developed in recent years. But these cost is higher than the conventional one due to additional control circuit, fast switching devces. In this paper, a novel pulse power supply for microwave oven using high frequency transformer embedded HVC(High Voltage Capacitor) is proposed for down-sizing, cost reduction and efficient improvement. To verify the effectiveness of the proposed transformer, an equivalent circuit of transformer embedded HVC is derived and it's characteristic is described. And the validity of the proposed pulse power supply embedded HVC-high frequency transformer is shown by simulations and experiments accroding to various operating conditions.

• 한국컴퓨터정보학회논문지
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• 제28권9호
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• pp.1-8
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• 2023

본 논문에서는 임베디드 시스템을 이용한 차량용 다기능 레이다(Multi-Function Radar, MFR) 수평구동장치(Auto-Leveling Equipment, ALE) 구동 전략을 제안한다. 차량용 레이다는 일정 속도로 회전하며 지대공 유도미사일, 유인/무인 전투기 감시정찰 임무를 수행한다. 수평구동장치는 수평구동모듈 4세트로 구성하고 레이다 차량의 수평을 유지하여 시스템의 안정성을 확보한다. 차량의 수평은 임베디드 시스템을 이용하여 경사도를 측정하고, 구동모터를 이용하여 차량의 수평각을 유지한다. 본 논문에서는 수평구동모듈 1세트를 모델링하여 수평구동장치를 축소 구현하여 수평구동장치 설계 향상에 기여한다. 제안하는 구동 전략의 타당성은 MATLAB/Simulink 시뮬레이션으로 입증한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1840-1845
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• 2005

The SoC and digital technology development recently enabled the emergence of information devices and control devices because the SoC present many advantages such as lower power consumption, greater reliability, and lower cost. It is required to use an embedded operating system for building control systems. So far, the Real-Time operating system is widely used to implement a Real-Time system since it meets developer's requirements. However, Real-Time operating systems reveal a lack of standards, expensive development, and license costs. Embedded Linux is able to overcome these disadvantages. In this paper, the implementation of control system platform using Real-Time Embedded Linux is described. As a control system platform, we use XScale of a Soc and build Real-Time control platform using RTAI and Real-Time device driver. Finally, we address the feasibility study of the Real-Time Embedded Linux as a Real-Time operating system for mobile robots.

• 대한임베디드공학회논문지
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• 제15권3호
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• pp.111-118
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• 2020

We investigate the optimization problem of transmit power control and MMSE Receiver filter for multi access points environment. Previous work showed that increasing the number of access points decreases the transmit power consumption. Accordingly, transmit power control algorithm was developed in such a way that the transmit power is minimized, while each terminal meets Signal to Interference and Noise Ratio Requirement. In this work, we further reduce the transmit power consumption by optimizing the transmit power level and the MMSE receiver filter together. We showed that the proposed joint optimization algorithm satisfies the necessary and sufficient conditions to be standard interference function, which guarantees convergence and minimum transmit power consumption. We observed that the proposed algorithm outperforms the algorithm which only optimizes the transmit power.