Direct current hybrid circuit breaker with reverse biased voltage source

A method of operating a direct current (DC) hybrid circuit breaker, the method comprising:

• detecting an over-current condition in a switch current across a closed mechanical switch in a mechanical switch path of the DC HCB, the mechanical switch path comprising a variable inductor and a mechanical switch;
• sending a signal from a current sensor in the mechanical switch path to a controller upon detecting the over-current condition;
• the controller controlling a gate in a semiconductor switch in a semiconductor switch path to close, thereby causing current to flow in the semiconductor switch path, wherein the semiconductor switch path is connected in parallel with the mechanical switch path, thereby causing the variable inductor in the mechanical switch path to desaturate;
• communicating a desaturation signal to the controller upon substantial desaturation of the variable inductor;
• and
• the controller controlling the gate in the semiconductor switch to open the semiconductor switch upon receipt of the desaturation signal.