Novel Step-Up Topologies of Zigzag Autotransformer
Zigzag autotransformer is widely used in multi-pulse rectifier system. However, the traditional zigzag autotransformer does not have the step-up function. Meanwhile, by improving the zigzag autotransformer structure, the output voltage can be increased without additional auxiliary components. Therefore, based on the 12 pulse rectifier system, this paper analyzes and designs three zigzag autotransformer step-up topologies, establishes the corresponding mathematical topology, studies the relationship between the transformation ratio and system main parameters, and deduces the step-up range of the three topologies. When the transformation ratio is greater than or equal to 1.0353 and less than 2.0705 and when the transformation ratio is greater than or equal to 2.0705, the equivalent capacity of the three topologies are compared. Based on the comparison, the optimal topology is obtained in different cases. Finally, according to the theoretical analysis, the simulation parameters are set, the simulation circuit is built, and the results are analyzed combined with corresponding mathematical topologies.