一种磁集成全桥LLC软开关焊接电源

An integrated magnetic full-bridge LLC soft-switching welding power supply

采用绕组绕制在EE型磁芯侧柱上的方法设计高频变压器,通过适当的绕组和气隙设计,使得高频变压器励磁电感和漏感满足LLC谐振电路参数的要求,LLC谐振槽中的两个谐振电感和变压器可以集成在同一磁芯上,减少变换器磁性元件个数,磁集成变换器可以提高效率,提高了变换器功率密度;同时,LLC磁集成焊接电源在整个负载工作范围内,实现原边开关管零电压开通,副边整流管实现零电流关断,降低损耗.在此基础上,研制2.5k W输出平特性的软开关全桥LLC磁集成焊接电源试验样机.结果表明,磁集成技术提高了系统性能.

By placing the windings in the outer leg of EE cores,the magnetizing inductor and leakage inductance of highfrequency transformer designed with suitable windings and air gap can meet the requirement of parameters for LLC converter. And the two inductors of LLC converter and the high-frequency transformer can be integrated in one EE core,so the number of magnetic components can be decreased,and the power conversion efficiency and power conversion density can be increased. Meanwhile,because of the integrated magnetic LLC resonant technique,the ZVS turn-on can be achieved for the primary side power switch,and the ZCS turn-off can be achieved for the secondary side rectifier diodes under the whole load ranges. The converter losses can be decreased dramatically. Finally,a welding power supply prototype with 2. 5 kW constant voltage output was developed. The experimental results show the performance of integrated magnetic LLC converter was improved.