Silicon-carbide (SiC) MOSFET–based solid-state circuit breakers (SSCBs) must bound transient drain–source voltage (VDS) during faults while avoiding steady-state stress on surge absorbers. A voltage clamping network is presented in which a gas-discharge tube (GDT) is placed in series with a metal-oxide varistor (MOV). The GDT isolates the MOV under normal conditions; after sparkover, the MOV clamps VDS, enabling higher DC-bus operation with lower-clamp MOVs. Analytical bounds on pre-sparkover overshoot and clamp margin guide selection of GDT sparkover, MOV parameters, and allowable loop inductance. Experimental validation on an SSCB prototype corroborates the analysis.
