Title |
Hybrid Current Mode Controller with Fast Response Characteristics for DC/DC Converter |
Authors |
Seung-Min Oh ; Seung-Woo Baek ; Hag-Wone Kim ; Kwan-Yuhl Cho |
DOI |
https://doi.org/10.6113/TKPE/2018.24.2.134 |
Keywords |
Super capacitor ; Peak current mode control ; Sub-harmonics oscillation ; Slope compensation |
Abstract |
A wide-bandwidth current controller is required for fast charging/discharging of super capacitor applications. Peak current mode is generally used to accomplish fast charging/discharging because this mode has fast response characteristics. However, the peak current mode control must have a slope compensation function to restrain sub-harmonics oscillation. The slope must be changed accordingly if the controlled output voltage is varied. However, changing the slope for every changed output voltage is not easy. The other solution, selecting the slope as the maximum value, causes a slow response problem to occur. Therefore, we propose a hybrid mode controller that uses a peak current and a newly specified valley current. Through the proposed hybrid mode control, the sub-harmonic oscillation does not occur when the duty is larger than 0.5 because of the fast response. |