| Title |
A Constant-Current and Constant-Voltage Control Method for Primary-Side Regulated Fly-Buck Converter |
| Authors |
Younghoon Cho ; Paul Jang |
| DOI |
https://doi.org/10.6113/TKPE.2023.28.1.30 |
| Keywords |
Fly-buck converter; Primary-side regulation; Constant-current control; Constant-voltage control |
| Abstract |
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. |