Operating a bi-directional double-base bipolar junction transistor (B-TRAN). One example is a method comprising: conducting a first load current from an upper terminal of the power module to an upper-main lead of the transistor, through the transistor, and from a lower-main lead of the transistor to a lower terminal of the power module; and then responsive assertion of a first interrupt signal, interrupting the first load current from the lower-main lead to the lower terminal by opening a lower-main FET and commutating a first shutoff current through a lower-control lead the transistor to the lower terminal; and blocking current from the upper terminal to the lower terminal by the transistor.