A High-Performance Low-Cost Resonant DC Load Switch Exclusively Utilizing Semi-Controlled Devices

The DC load switch provides a solution for the repeated switching of load currents in DC distribution systems, ensuring their flexible operation. However, existing DC load switches suffer from high costs and poor reliability. Therefore, this paper introduces the resonant DC load switch based on thyristor-LC circuit (TLC-RLS), which exclusively utilizes semi-controlled devices. It leverages the continuous turn-on and turn-off of thyristors to rapidly create multiple zero-crossing points for the mechanical switch (MS). Compared to fully controlled devices, thyristors offer lower costs, stronger surge capability, and higher reliability, with a simple triggering mechanism that eliminates electromagnetic compatibility issues. This characteristic enables the TLC-RLS to achieve low costs while maintaining high performance. This paper initially presents the topology and operational principles of the TLC-RLS. Subsequently, considering the thyristor's reverse recovery process, a comprehensive parameter design method is proposed. A 10 kV/3 kA prototype is constructed to validate the accuracy of the topology and parameter design, as well as to verify the interruption capability at lower current levels.