Analysis of balance controllers for cascaded modular solid-state transformer during steady-state, transient and fault conditions

Abstract:

Cascaded Modular Solid-State Transformer (CMSST) is proposed as an alternative to the conventional transformer for smart grids where controlled bidirectional power flow, provision to integrate distributed generation, grid support with ancillary services and feasibility for islanded operation have become absolute necessity. Even though CMSST is modular in design (both phase-wise and system-wise), voltage balance controllers (VBC) and power balance controllers (PBC) are still required to compensate the mismatches in passive elements of various modules. The design and control philosophy of VBC and PBC are well understood in the literature, however, influence of these balance controllers on steady-state and fault performance is less studied. In this paper, analysis of balance controllers during steady-state, transient and faulty conditions are studied interms of harmonics in grid current, bandwidth of system and choice of fault indicators. The presented analysis is substantiated with experimental results from a 1 kV A CMSST prototype. These findings can serve as a good starting guidelines while choosing appropriate balance controllers for CMSST.

Año de publicación:

2020

Keywords:

Fuente:

scopus