A New Multi-Loop Digital Control DC-DC Converter
Sukita, S.; Sakemi, J. (Graduate School of Science and Technology, Nagasaki University, Japan)
This paper presents a new multi-loop digital control circuit which is able to detect not only the average output voltage but also the output current and input voltage of the dc-dc converter. The proposed digital control circuit consists of the three A-D converters, one DSP and the digital PWM circuit. In this proposed digital control circuit, the output voltage is used for the digital P-I-D control, the load resistance is calculated using the output voltage and current and then the moving average of the load resistance is obtained for another control loop. As a result, it is clarified that the transient time is suppressed to within 1.15ms and this result is approximately 84% smaller than the conventional static model controlled dc-dc converter. Especially, the overshoot of reactor current is suppressed to within 68% and this result is approximately 50% smaller than that of the conventional control method. It is confirmed that the proposed multi-loop control technique is useful to realize the high performance digital control circuit of dc-dc converter.
