• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1999년도 전력전자학술대회 논문집
• /
• pp.618-621
• /
• 1999

With the advent of the high-speed microprocessor and DSP, the possibility of executing a control strategy in digital domain has become a reality. By the use of the DSP and microprocessor controller, many high power drive system may be enhanced resulting in the improved robustness to EMI, the ability to communicate the operating conditions and the ease of adjusting the control parameters. But, the digital controller using DSP or microprocessor is not applied in the high frequency switching power supplies, especially full bridge DC/DC converter. So, this paper presents the method and realization of designing a digital-to-phase shift PWM circuit for full digital controlled full bridge DC/DC converter with zero voltage switching. The operating principles, simulation and experimental results will be presented.

• Journal of Power Electronics
• /
• 제12권1호
• /
• pp.88-97
• /
• 2012

This paper presents a method for the digital control of a high power factor AC/DC converter employing the power balance control technique to achieve a fast response of the output voltage control. To avoid the effects of an output voltage ripple in the voltage control loop, the average output voltage is sampled and used as a feedback signal for the output voltage controller. The proposed control technique was verified by simulations using MATLAB/Simulink and its implementation was realized by a dsPIC30F4011 digital signal processor to control a CUK topology AC/DC converter with a 48V output voltage and a 250 W output power. The experimental results agree with the simulation results. The proposed control technique achieves a fast transient response with a lower line current distortion than is achieved when using a conventional proportional-integral controller and the power balance control technique with the conventional sampling method.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
• /
• pp.690-692
• /
• 2004

Differently from an existing analog control, because the digital control includes microprocessor basically, the digital control is enable to monitor internal parameters of DC-DC converter and to control output voltage remotely by communicating with a Windows based PC and also to monitor whether exact voltage is output or not. These things are impossible in an analog control. In this paper, a simple flyback converter is taken as a control target and is controlled by a microcontroller(TMS320F2812). This converter can make variable outputs 1.8V to 5V from 30V input voltage remotely in PC. Finally the response characteristics of a step reference voltage and in a steady state are experimented to verify the feasibility and the usefulness of this digital controlled converter.

• 전자공학회논문지SC
• /
• 제41권6호
• /
• pp.67-74
• /
• 2004

기존의 아날로그 제어방식과는 달리 디지털 제어 방식은 기본적으로 마이크로프로세서를 포함하고 있기 때문에 아날로그 제어방식에서는 할 수 없었던 DC-DC 컨버터 내부 파라미터에 대한 모니터링이 가능하며, 아날로그 제어방식에서는 처음의 사양에 의해 고정된 출력전압을 얻었지만 디지털 제어 방식에서는 PC와 DC-DC 컨버터의 통신을 통하여 사용자가 원하는 임의의 전압을 얻어낼 수 있고 원격제어가 가능하다. 또한 PC와의 통신을 통해 원거리에 있는 DC-DC 컨버터에 정확한 전압이 출력되고 있는지 또는 비정상적인 전압이 출력되고 있는지를 감시, 진단할 수 있다는 장점을 가지고 있다. 본 논문에서는 이와 같은 디지털 제어기의 장점과 함께 디지털 제어기의 저가격화에 대한 실용성을 제시하고자 하였다. 이러한 기능들을 구현하기 위해 AD 컨버터와 PWM 로직이 내장되어 있는 저가의 정수형 On-chip 마이크로 콘트롤러인 Renesas사의 H8/3672를 사용하였다. 디지털 제어기는 Flyback 컨버터에 적용되었으며, DC 20∼30V 입력으로부터 기본 DC 5V 출력전압을 갖도록 설계되었고, 또한 에뮬레이터를 이용하여 PC상에서 원격으로 DC 0V에서 DC 5V이상까지의 다양한 출력 전압을 만들 수 있다. PWM의 듀티(Duty) 제어를 위한 제어기로써는 PID제어기 중에서 PD제어기를 사용하였다. 본 논문에서 설계된 디지털 제어방식 컨버터의 실용성을 검토하기 위해 과도상태의 특성과 정상 상태의 특성을 분석하여 정수형의 저가형 마이크로 콘트롤러를 이용한 Flyback 컨버터의 실용성을 검토하였다.

• Journal of Power Electronics
• /
• 제19권1호
• /
• pp.220-233
• /
• 2019

This work aims to study and analyze the various operating modes of universal power converter which is powered by solar and thermoelectric generators. The proposed converter is operated in a DC-DC (buck or boost mode) and DC-AC (single phase) inverter with high efficiency. DC power sources, such as solar photovoltaic (SPV) panels, thermoelectric generators (TEGs), and Li-ion battery, are selected as input to the proposed converter according to the nominal output voltage available/generated by these sources. The mode of selection and output power regulation are achieved via control of the metal-oxide semiconductor field-effect transistor (MOSFET) switches in the converter through the modified stepped perturb and observe (MSPO) algorithm. The MSPO duty cycle control algorithm effectively converts the unregulated DC power from the SPV/TEG into regulated DC for storing energy in a Li-ion battery or directly driving a DC load. In this work, the proposed power sources and converter are mathematically modelled using the Scilab-Xcos Simulink tool. The hardware prototype is designed for 200 W rating with a dsPIC30F4011 digital controller. The various output parameters, such as voltage ripple, current ripple, switching losses, and converter efficiency, are analyzed, and the proposed converter with a control circuit operates the converter closely at 97% efficiency.

• 조명전기설비학회논문지
• /
• 제25권7호
• /
• pp.32-39
• /
• 2011

FPS(Filament Power Supply), one of the KSTAR NBI(Neutral Beam Injections) is implemented by full-bridge DC/DC converter. NBI heating device for KSTAR(1.5MW) is developed for heating an ion source of plasma in KSTAR tokmak. The full-bridge DC/DC converter is applied to FPS for isolation with input and output. And FPS is operated with PWM control method which is the most usual method. In this paper, NBI FPS of 4.8kW is simulated by using the PSIM 6.0. And the full-bridge DC/DC converter using IGBTs is fabricated to demonstrate it. The processor DSP 28335 is implemented for digital control.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
• /
• pp.807-810
• /
• 2004

This is a experimental result which is reported with using 16-Bit microprocessor H8 series of Renesas company, organizing digital control which is practicable PWM embodiment, and applying switched-mode power supply. The basic topology consists of the active clamp forward DC-DC converter which is widely used for the highly efficient power supply these days. In an experiment, it incites the result to lay emphasis on the highly efficient operation of converter, and performance of digital control which is practicable PWM embodiment. And it is debated on performance of processor and condition for improving performance of part.

• Journal of Power Electronics
• /
• 제9권3호
• /
• pp.430-437
• /
• 2009

This paper presents the dynamic characteristics of buck and buck-boost dc-dc converters with digital filters. At first, the PID, the minimum phase FIR filter and the IIR filter controls are discussed in the buck dc-dc converter. Comparisons of the dynamic characteristics between the buck and buck-boost converters are then discussed. As a result, it is clarified that the superior dynamic characteristics are realized in the IIR filter method. In the buck converter, the undershoot is less than 2% and the transient time is less than 0.4ms. On the other hand, in the buck-boost converter, the undershoot is about 3%. However, the transient time is approximately over 4ms because the output capacitance is too large to suppress the output voltage ripple in this type of converter.

• Journal of Power Electronics
• /
• 제17권3호
• /
• pp.686-694
• /
• 2017

Due to the wide use of electronic products, digitally controlled DC-DC converters are attracting more and more attention in recent years. However, digital control strategies may introduce undesirable Limit Cycle Oscillation (LCO) due to quantization effects in the Analog-to-Digital Converter (ADC) and Digital Pulse Width Modulator (DPWM). This results in decreases in the quality of the output voltage and the efficiency of the system. Meanwhile, even if the resolution of the DPWM is finer than that of the ADC, LCO may still exist due to improper parameters of the digital compensator. In order to discover how LCO is generated, the state space averaging model is applied to derive equilibrium equations of a digital PID controlled DC-DC converter in this paper. Furthermore, the influences of the parameters of the digital PID compensator, and the resolutions of the ADC and DPWM on LCO are studied in detail. The amplitude together with the period of LCO as well as the corresponding PID parameters are obtained. Finally, MATLAB/Simulink simulations and FPGA verifications are carried out and no-LCO conditions are obtained.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2010년도 하계학술대회 논문집
• /
• pp.485-486
• /
• 2010

FPS(Filament Power Supply), one of the KSTAR NBI (Neutral Beam Injections) is implemented by full-bridge DC/DC converter. NBI heating device for KSTAR(1.5MW) is developed for heating an ion source of plasma in KSTAR tokmak. The full-bridge DC/DC converter is applied to FPS for isolation with input and output. And FPS is operated with PWM control method which is the most usual method. In this paper, NBI FPS of 4.8kW is simulated by using the PSIM 6.0. And the full-bridge DC/DC converter using IGBTs is fabricated to demonstrate it. The processor DSP 28335 is implemented for digital control.