Analysis of a cascaded high-boost non-isolated DC-DC converter with bidirectional power flow

This paper analyses the performance of a modified boost topology derived from a classic boost converter with higher gain for applications in motor drive operation. The bidirectional power management of the boost converter is enhanced by connecting the dc link capacitor across the boost inductor, rather than across the DC-link. The voltage regulation of the output capacitor and the average current control for the boost inductor are achieved by two PI controllers. Compared with the single switch operation, the two-switch boost converter features full regenerative operation with improved voltage regulation, while retaining the advantage mentioned above. The paper evaluates performance of a 3-level modular cascaded DC-DC converter which offers multi-stage dc input and output connections with high boost and redundancy for power management. Simulation studies of the converter supplying a motor drive operation with fast acceleration and deceleration demonstrate the bi-directional power flow and proper current sharing between cascaded stages.