Fault-tolerant control of a grid-connected bipolar DC microgrid with high penetration of intermittent renewable energy

Abstract

Bipolar DC grids are gaining great attention in modern power systems due to their superiority over Unipolar DC grids and AC grids. Existing studies on DC microgrid operations and controls individually investigate voltage control and balancing, power-sharing, and fault-tolerant operation. However, simultaneous investigation of voltage control, balancing, fault-tolerant operation and maximizing intermittence renewable energy in bipolar dc grids is important to understand the overall system behaviour. This paper presents a grid-connected bipolar DC microgrid architecture and control strategies to maximize the intermittence renewable energy usage, and reliable operation under fault conditions. The proposed DC microgrid can ensure reliable operation under healthy and faults conditions while utilising a high percentage of renewable energy, being verified through numerical results.