Search

Cascaded dc–dc converter is the main component of the dc distributed power system. It is valuable to establish the accurate model for studying the stability of cascaded dc–dc converters. However, the cascaded dc–dc system has many operating modes, such that the existing classic methods, e.g., state-space average model and discrete-mapping model, are difficult to explore to analyze cascaded dc–dc converter system, especially that with different switching frequencies. To overcome this drawback, this article promulgates a new modeling and stability analysis method for cascaded dc–dc converter. Small-step method, discretization method, and Euler method are exploited to modeling. All stages of the system are considered, therefore, accurate; and stability is divided into three categories according to the different definitions. Then, the cascaded systems with the same or different switching frequencies are studied using the presented method. As an example, two-stage peak current-mode controlled boost converter is scrutinized. Finally, simulations and experiments are manipulated to verify the correctness of the new method. [ABSTRACT FROM AUTHOR]

Summary: With the rapid development of renewable energy, inverters have been widely used in the distributed power system. For the safety of the distributed power system, the stable operation of the inverter is vital. Hence, this paper detects slow‐scale instability fast‐scale instability and in the double‐loop proportional‐integral (PI) control single‐phase full H‐bridge inverter with inductive impedance load by the discrete‐mapping model firstly. Next, the mechanism of the mechanism slow‐scale and fast‐scale behaviors are explained by state‐space average model and Filippov method, respectively. Then, passive damping method and sine wave compensation techniques are extended to the system to suppress the nonlinear behaviors. Finally, the PLECS simulation and experiments are utilized to verify the correctness of the investigations. [ABSTRACT FROM AUTHOR]