| Title |
Optimal Hysteresis Control for CCM Driving of a Single-Stage PFC Flyback Converter for LED Lightings |
| DOI |
https://doi.org/10.5370/KIEE.2016.65.4.586 |
| Keywords |
Flyback converter ; PFC ; CCM ; Hysteresis control ; LED |
| Abstract |
The current control of Continuous Conduction Mode(CCM) can be implemented by several methods: peak current control; average current control; and hysteresis control. Among these methods, the hysteresis current control is popularly applied in various converter applications because of its simplicity of implementation, fast current control response and inherent peak current limiting capability. However, a current controller with conventional hysteresis band which multiplies the current reference has the disadvantage that the modulation frequency varies in one cycle of the input voltage and, as a result, generates high switching frequency in the low input voltage section. Also it is complicated to design the input filter due to varying switching frequency. This paper proposed an optimum hysteresis-band current control method where the band is generated by using both multiplication method and sum method to maintain the modulation frequency to be nearly constant. This approach can solve the high switching frequency in the low input voltage section, and achieve easy design of input filter. The performance of the proposed converter is verified with the simulation and the experimental works. |