Protection of DC Bus using Solid-State DC Breaker

In this contemporary era, DC micro grids are become trendy. DC micro grids have numerous advantages as well as disadvantages. One of the main drawbacks of DC micro grid is short-circuiting protection; it has become a challenging issue because of the high rise rate the fault current. Electro-mechanical switches are very slow which cannot control the short circuit faults resulting in over dimensioning of the system. Power electronic circuit breakers have the ability to interrupt high magnitude of fault currents. This paper introduces a new concept of Bi-directional Short-Circuit Current Blocker based on Solid-State Circuit Breaker (SSCB). The new Solid-State circuit Breaker detects the short-circuit faults by using Current Differential Protection strategy. The SSCB can be directly placed in series with the DC Bus without disturbing the normal circuit. Finally, the performance of the blocking circuit is simulated and results are verified. The results clearly show that, by using SSCB short-circuit fault current is blocked within 4 ms. The SSCB gives better results than any other protection mechanism developed until now and has many benefits such as reclosing, bi-directional blocking and energy releasing functions. SSCB can be used numerous times and the best solution for short-circuit faults.