基于桥式拓扑的脉冲变压器隔离驱动器优化设计

Transformer Isolation Drives Optimization Design Based on the Bridge Topology

针对目前桥式拓扑驱动中,因脉冲变压器隔离驱动器与MOSFET制造和安装过程中引入寄生参数,导致波形畸变及耦合干扰,从而引起驱动桥式拓扑过程中功率器件损坏和开关损耗大等影响驱动器品质的问题。给出引入寄生参数的脉冲变压器隔离驱动器驱动电路等效模型,在此基础上分析产生上述问题的内在机理,并以此为依据进行参数及电路优化,最后通过实验结果表明优化后的驱动信号具有最小的波形失真,驱动电压脉冲的前沿、后沿具有合适的陡度及合适的顶降,从而使MOSFET工作于最佳的开关过程,可有效地保证桥式拓扑电路安全可靠地运行。

According to the present bridge topological drives, the parasitic parameters introduced in the process of the pulse transformer isolation drives and MOSFET manufacture and installation can lead to the waveform distortion and coupling interference, they cause the problems, such as the power device damage in the process of driving type topology and big switching loss, and the quality of the drivers will be affected by these problems. Considering all the parasitic parameters, a pulse transformer drive circuit equivalent model was given, and on the basis of the deep analysis of how each parameter produce the above problems, the parameters and circuit were optimized. Finally, the experimental results show that the optimized drive signal has the smallest waveform distortion, the driving voltage pulse front edge and back edge have appropriate gradient and suitable top and down, so that the MOSFET work in the best switching process, it can effectively guarantee bridge topological circuit safe and reliable operation.