Current Limiter Circuit to Suppress Inrush Load Current for LVDC Distribution System

This paper proposes an analysis of the inrush load current and a design of the inrush current limiter circuit for a low-voltage DC (LVDC) distribution system. Due to the absence of a zero-crossing point, large fault current during the connection of DC loads with a large input capacitor may cause severe problems in the LVDC distribution system including voltage drop on the DC bus and damage to the system. To analyze the necessity of a current limiter circuit, the voltage control system of a TAB converter for the LVDC distribution system is designed. The stability under the inrush current is analyzed through the small-signal modeling of the TAB converter. Also, the inrush current limiter circuit composed of a switch, a diode, and an inductor is proposed. To obtain the desired current suppression performance, the design methodology is presented. The validity of the proposed inrush current limiter is verified by a lab-level LVDC distribution system with a 4-kW TAB converter prototype.