Double Resonant Tanks LLC Resonant Converter Based on Magnetic Control
ZHENG Hong;YAN Xuwen;YUAN Xuekai;QIN Runtian;YOU Tao;College of Electrical and Information Engineering, Jiangsu University;
LLC resonant converter can realize the zero voltage switching(ZVS)of primary switching transistor and the zero current switching(ZCS)of the secondary rectifier transistor with high conversion efficiency. However, the traditional LLC resonant converter has the disadvantages of narrow input voltage range and low efficiency in wide input voltage range. In view of this shortcoming, through the improvement of topology and control method, a full-bridge double resonant tanks LLC resonant converter is proposed, which uses variable inductance controlled by magnetism to realize output voltage control and regulation in constant frequency mode, and greatly broadens the input voltage without sacrificing efficiency. An experimental prototype with the input of 120 V-400 V and the output of 48 V/5 A is assembled, which verifies the rationality of the theoretical analysis.