一种新型三电平智能变压器的研究

Research on three-level intelligent transformer

研究了一种新型的三电平智能变压器拓扑。以SEPIC变换器为例,将多电平技术应用到智能变压器中,使得开关管的电压应力得到大幅下降,同时也减小了滤波器的体积。分析了其工作原理和开关模态,并设计了带电容均压控制的电压瞬时值反馈控制策略。最后,完成了一台500 W单相原理样机,通过实验验证了新型拓扑及控制策略的正确性,充分体现了SEPIC式三电平智能变压器的优越性。

This paper proposes a new topology structure of three-level intelligent transformer. Firstly ,researches the topology structure of SEPIC three-level intelligent transformer. The multi-level technology is applied to the topology, which can obviously re-duce the voltage stress of switches and the volume of fiher. Secondly, analyzes its working principle and switching mode, and de-signs transient voltage feedback control strategy with same capacitor voltage. In the end, a single phase principle prototype is made to verify the feasibility of new topology and correctness of control strategy. By experiment, results show excellent performance of prototype, and fully reflect the superiority of SEPIC three-level Intelligent Transformer.