Distributed type high-frequency conversion-based modular solid-state transformer and control method therefor

The invention discloses a distributed type high-frequency conversion-based modular solid-state transformer and a control method therefor. The modular solid-state transformer comprises multiple cascaded modules; each module comprises two sub converters SCi1 and SCi2, a high-frequency transformer and an auxiliary inductor L, wherein i represents the i module; each sub converter consists of four power sub modules; the structure of the power sub module can be a half-bridge type structure or a full-bridge type structure; each half-bridge type structure comprises a capacitor, two IGBTs and adiode in anti-parallel connection with the IGBTs; each full-bridge type structure comprises a capacitor, four IGBTs and a diode in anti-parallel connection with the IGBTs; the input end of the transformer is in a high voltage; multiple modules are connected in series to be used as the input end; the output end of the transformer is in a low voltage; and multiple modules are connected in parallel to be used as the output end. By