제어 방식에 따른 20 W급 LED Converter 설계 및 분석

정영기,김성현,박대희,Jeong, Young-Gi,Kim, Sung-Hyun,Park, Dae-Hee 한국전기전자재료학회 2012 전기전자재료학회논문지 Vol.25 No.1

In this paper, by designing 20 W class driving circuit for driving high-power LED (Light Emitting Diode), we are going to comparatively carry out the analysis of characteristics for power circuit according to each design method. In this case, 200 V 60 Hz was performed as input data. The electrical characteristics such as voltage, current and ripple are checked for constant current circuit and constant voltage circuit in the LED module. In addition, as the ripple has an influence on illumination of LED light, low temperature working (-20 [$^{\circ}C$]) and high temperature working(80 [$^{\circ}C$]) are measured to make sure the ripple characteristics in accordance with temperature. In low temperature operation -20 [$^{\circ}C$] measurements, both constant current circuit and constant-voltage circuit were less impacted on input fluctuation, whereas in the high temperature operation 80 [$^{\circ}C$], current voltage in constant voltage circuit was surge after 430 [hour]. Voltage current ripple of constant current circuit was much less than constant voltage circuit, therefore we can show that constant current circuit is more stable.

Improved Multilevel Multistage Constant-Current Constant-Voltage Superfast Charging of Multiple Cells

Yun Sang-Sun,Kee Seok-Cheol 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.1

The increasing energy density from primary to secondary batteries has greatly expanded their applicability. For instance, electric vehicles have emerged to comply with environmental-friendly development. Yet, unlike gasoline vehicles, electric vehicles require long periods to charge their batteries. To reduce the charging time, the multilevel constant-current constantvoltage method has been developed. However, overvoltage protection is activated in the battery management system when using this method because a transient response occurs at the intersection of the constant current and constant voltage due to capacity deviations between multiple cells in a battery. The voltage can be prevented from rising to the charge cutoff level by adopting various constant voltages. Hence, we propose multilevel multistage constant-current constant-voltage superfast charging that varies the charge voltage according to the charge current. The proposed charging technique has a smaller charging rate than the conventional charging method by approximately 3%, but it prevents forced charging shutdown due to overvoltage protection activation in the early stage of superfast charging by providing a stable charge voltage. The performance of the technique was verifi ed through simulations of a real environment, and the improved technique was further evaluated over longer periods through additional simulations.

Design of a High-Precision Constant Current AC-DC Converter with Inductance Compensation

Chang, Changyuan,Xu, Yang,Bian, Bin,Chen, Yao,Hu, Junjie The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

A primary-side regulation AC-DC converter operating in the PFM (Pulse Frequency Modulation) mode with a high precision output current is designed, which applies a novel inductance compensation technique to improve the precision of the output current, which reduces the bad impact of the large tolerance of the transformer primary side inductance in the same batch. In this paper, the output current is regulated by the OSC charging current, which is controlled by a CC (constant current) controller. Meanwhile, for different primary inductors, the inductance compensation module adjusts the OSC charging current finely to improve the accuracy of the output current. The operation principle and design of the CC controller and the inductance compensation module are analyzed and illustrated herein. The control chip is implemented based on a TSMC 0.35μm 5V/40V BCD process, and a 12V/1.1A prototype has been built to verify the proposed control method. The deviation of the output current is within ±3% and the variation of the output current is less than 1% when the inductances of the primary windings vary by 10%.

Design of a High-Precision Constant Current AC-DC Converter with Inductance Compensation

Changyuan Chang,Yang Xu,Bin Bian,Yao Chen,Junjie Hu 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

A primary-side regulation AC-DC converter operating in the PFM (Pulse Frequency Modulation) mode with a high precision output current is designed, which applies a novel inductance compensation technique to improve the precision of the output current, which reduces the bad impact of the large tolerance of the transformer primary side inductance in the same batch. In this paper, the output current is regulated by the OSC charging current, which is controlled by a CC (constant current) controller. Meanwhile, for different primary inductors, the inductance compensation module adjusts the OSC charging current finely to improve the accuracy of the output current. The operation principle and design of the CC controller and the inductance compensation module are analyzed and illustrated herein. The control chip is implemented based on a TSMC 0.35μm 5V/40V BCD process, and a 12V/1.1A prototype has been built to verify the proposed control method. The deviation of the output current is within ±3% and the variation of the output current is less than 1% when the inductances of the primary windings vary by 10%.

1차 측 제어 플라이벅 컨버터의 정전류 및 정전압 제어

조영훈,장바울 전력전자학회 2023 전력전자학회 논문지 Vol.28 No.1

In this paper, a constant current(CC) and constant voltage(CV) control method using a primary-side regulated(PSR) fly-buck converter is proposed. Because the primary-side structure of the fly-buck converter is the same as that of the synchronous buck converter, it always operates in continuous conduction mode(CCM). Therefore, in the proposed method, the load information on the secondary side can always be easily estimated by measuring the primary inductor current at the midpoint of the switch-on period. An accurate CC/CV control can be achieved through simple calculations based on this estimated information. Consequently, the proposed method is advantageous for optimizing the control performance of the PSR converter. The validity of the proposed control was verified using a 5 W prototype of a PSR fly-buck converter. The experimental results confirmed that the current reference of 500 mA was followed within the error range of 1.2%, and that the voltage reference of 12 V was followed within the error range of 1.8% despite the indirect control of the load current and output voltage from the primary side.

고효율 스위칭에 의한 정전류 조정 교류전원 제어시스템

임병국 忠州大學校 2009 한국교통대학교 논문집 Vol.44 No.-

This paper proposed an improved inverter systems with constant current regulation based on improved measuring technique of feedback current. To improve the response and precision of the measured current, moving average method of instantaneous currents was applied. Also, high frequency switching techniques was used to decrease the ching loss of inverter. By applying double-carrier modulation, the efficiency of the inverter system was improved. The proposed algorithm was verified by experiment using DSP TMS320C33. The experimental results shows that the proposed measuring technique of feedback current has fast-response. This proposed system may be used various applications including on-line type UPS, VVVF inverter, solar cell system and fuel cell.

PSR CC/CV AC-DC converter with an adaptive high-precision closed-loop constant current control scheme

Gu, Yang,Ju, Dongqian,Wang, Lei,Ren, Jie,Chang, Changyuan The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.7

A primary-side regulation (PSR) constant current (CC) output and constant voltage (CV) output AC-DC converter is proposed and an adaptive high-precision closed-loop constant current control scheme is put forward in this paper. In the CC mode, the converter adopts the closed-loop control strategy to realize that the switching period adaptively converges to twice the demagnetization time, which realizes the CC output. In addition, exactly detecting the demagnetization time is a prerequisite for obtaining a high-precision output current. Therefore, a demagnetization time detection circuit is designed to provide accurate and reliable demagnetization information. The control IC was fabricated with the Nuvoton 0.5um BCD process, and a 5 V/2 A prototype circuit was implemented to verify its performance. Experimental results show that the CC deviation is within ± 1.4%, which is lower than the target value of ± 2.0%. Under different loads and AC inputs, the conversion efficiency in the CC mode varies between 76.3% and 80.7%.

Characteristic analysis of new hybrid compensation topology for wireless charging circuits

Wang, Huanmin,Chen, Yao,Zhang, Hui,Zhang, Shangzhou The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.9

Wireless power transfer (WPT) has the advantages of flexibility, safety, and high reliability. Thus, it is widely used in portable electronic equipment, electric vehicles (EV), medical equipment, and other fields. The resonance compensation method of wireless charging directly affects the gain characteristics of the output current and voltage. As a result, this is one of the main research focuses of wireless power transmission technology. A new hybrid compensation topology circuit is proposed in this paper, which is based on the EV constant-current (CC) and constant-voltage (CV) charging mode. In this hybrid topology circuit, an equivalent loosely coupled transformer T model is established for the primary and secondary coils. Through an analysis of the circuit principle, it is concluded that the wireless power transmission circuit can realize CC and CV outputs under a dynamic load change. The output power efficiency characteristics of the serial/parallel (S/P) compensation and serial/serial (S/S) compensation circuits are analyzed. In addition, the mutual inductance parameters are optimized by an efficiency power product method to achieve the overall optimal parameter design in terms of the circuit output power and efficiency. A simulation model and an experimental prototype of the wireless power transmission circuit are established. The design process of the circuit parameters under a given target current and voltage is also presented. The simulation verifies the correctness of the constant current and constant voltage output of the S/P-S/S hybrid compensation circuit. The experimental platform verifies the CC output under the S/P compensation topology, and the CV output under the serial/serial (S/S) compensation topology.

Improved Stability of AlGaN/GaN Heterojunction Schottky-diode-type Hydrogen Sensor Using Constant Current Source Operation

June-Heang Choi,Hyungtak Kim,Ho-Young Cha 대한전자공학회 2020 Journal of semiconductor technology and science Vol.20 No.5

An AlGaN/GaN heterojunction Schottky-diode-type hydrogen sensor was fabricated with Pd catalyst and exhibited excellent response characteris-tics. The sensor was operated in two different modes: constant voltage and constant current bias modes. Since the diode current has an exponential relationship with its forward voltage, any small fluctuations or drift in the bias voltage results in large variations in the output current. Using a constant current bias mode of operation thus allowed more stable sensing characteristics for the Schottky-diode-type hydrogen sensor.

군용레이더 전원공급장치의 p-Channel MOSFET 돌입전류 제한 회로 개선에 관한 연구

정성빈,윤재복 한국기계기술학회 2023 한국기계기술학회지 Vol.25 No.5

Despite the presence of the p-Channel MOSFET inrush current limiter circuit within the power supply unit of military radar, The internal MOSFET and DC-DC Converter has been damaged due to the high inrush current. In this paper, the cause of the high inrush current was identified by analyzing the p-Channel MOSFET inrush current limiter circuit. Based on the analysis, the high inrush current was reduced by about 60% by adjusting the time constant of the source-to-gate elements compared to before improvement.