Multilevel PFC circuits are widely used in medium and high-voltage applications. However

conventional multilevel topologies suffer from the large number of semiconductor devices and the lack of obvious expansion methods. In this paper

a new multilevel topology based on the full binary tree structure (MT-FBT) is derived by combining multilevel construction methods with a three-level clamp unit as the starting point. This topology has a high degree of modularity

an exponential trend of 2 in the number of output levels and structure layers

and an advantage over traditional multilevel topologies in terms of the number of devices. In this paper

the derivation process and its general form is obtained. On this basis

the expansion method and clamping principle are elaborated. Then

the four-level converters extended by the MT-FBT are analyzed in detail in terms of working principle

PWM modulation strategies and control methods. Finally

experimental prototypes with rated power of 1 kW are designed and built. The experimental results verify the feasibility of the MT-FBT and the engineering application value of the derived converters.