Study on a Fuzzy Controller for the Balance of Capacitor Voltages of Three-Level Boost Dc-Dc Converter

A fuzzy control strategy is presented to implement the neutral-point (NP) potential balance based on the power stage of three-level Boost dc-dc converter in this paper. The presented fuzzy controller can solve the imbalance problem of NP potential in the process of starting up and can suppress the influence of inverter circuit modulation strategy on NP potential. It is the fuzzy controller that can adaptively change duty cycle ratio to implement the balance between the output capacitor voltages, not only in the process of starting up, but also in steady operation state. The fuzzy controller has been designed in this paper and the control rules have been given to achieve perfect dynamic and steady performance. Finally, the simulation and experimental results verify the feasibility and reliability of this methods way and the method presented in this paper implemented only by digital control, so this method does not need to add extra hardware. Finally, the experimental results verify the method.