Analysis and improvement of cross-regulation effect in the primary side-regulated multi-output flyback converter

作者：Guo, Xifeng^*; Luan, Fangjun; Liu, Jian; Liu, Meiju

来源：International Journal of Circuit Theory and Applications, 2017, 45(9): 1299-1312.

DOI：10.1002/cta.2312

• cross regulation
• stacked topology
• primary side-regulated
• analytical model
• flyback converter

In the multi-output primary side-regulated (PSR) flyback converters, cross-regulation effect denotes the phenomenon that change of load current in either one of the outputs would lead to the output voltage variations in other output terminals. Because the PSR flyback converters are frequently used to provide power supplies in a power system, the steady operation of the power system may be affected. Based on an improved Cantilever model, this paper proposes a thorough analysis on the cross-regulation effect in the PSR flyback converter. It has been found that the coupling between the output windings and the topology of the output terminal would have significant influence on the cross-regulation effect. Moreover, a mathematical expression has been derived to calculate the relationship, in the time domain, between the voltages of the output windings in the PSR flyback converter. In the mathematical expression, the leakage inductances in the improved cantilever model are lumped into a matrix R'. Hence, the winding method and the geometry of the transformer can be optimized to improve the precision of the multi-output voltages in the PSR flyback converter. A 10-W PSR flyback prototype with three output terminals is built. Experimental results are given to validate the theoretical analysis.

• 出版日期2017-9
• 单位沈阳建筑大学