This invention discloses a coordinated control method for a multi-module cascaded
solid-state
transformer, relating to the field of
power electronics technology. The
solid-state
transformer includes multiple power conversion units, each employing a combined topology of front-end and rear-end conversion modules. Through the
synergy of front-end
voltage build-up control and rear-end
optimal trajectory soft-start control, a phased and controllable soft-start strategy is constructed. First, the front-end actively builds up and equalizes the input buses at each stage, boosting and stabilizing the
bus voltage within a safe operating range for startup, providing approximately constant input conditions for the rear-
end stages. The rear-
end stages employ an
optimal trajectory control strategy, constraining the evolution paths of resonant current and
capacitor voltage to achieve controlled power delivery, reducing problems such as overshoot, current surges, and excessive device stress during startup. Simultaneously, on the output side, phased control and a smooth transition mechanism ensure that the output voltage gradually builds up along a predetermined trajectory. After the
system enters the steady-state operation stage, a post-stage steady-state optimization control method is proposed. The allocation coefficients of each module are used as unified optimization variables. The optimal allocation result is solved by a resource-aware distributed
differential evolution algorithm. The allocation result is mapped to specific control inputs through the local controllers of each module, thereby optimizing the adaptive and coordinated operation mechanism of the post-stage
system.