A Study on Power Flow Control and DC Circuit Breaker Stress Reduction Using DC Power Flow Control Converter

The method proposed in this paper controls the power flow of the meshed DC power system using a DC Power Flow Control Converter (PFCC), and reduces the fault current that occurs in the case of a short circuit in a DC circuit. It is a method to lower the fault current flowing through the DC circuit breaker and thus to reduce the stress applied to the circuit breaker. The proposed PFCC is a Dual Active Bridge (DAB) Converter consisting of a DC/AC power converter connected in parallel with the DC system, a high-frequency transformer that transforms voltage, and a DC/AC power converter, and It consists of a full bridge converter that is connected in series with a DC line and outputs a constant voltage and a reverse voltage, and controls the voltage of the grid line. In this paper, simulation was performed by applying PFCC to a mesh-type DC power system through MATLAB/Simscape, and performance and feasibility were verified through Cassie method to analyze the characteristics of DC circuit breakers.