Development of self-conducting current bypass circuit for series-connected diodes in high power semiconductor light source

This paper proposes a self-conducting current bypass circuit for series-connected diodes in high power semiconductor light source. This circuit enables the main circuit current flow continuously, even if several of the diodes connected in series are open because of breakdowns. Herein, the composition, operation, and circuit design method of the proposed circuit are described. Moreover, the development of a simulation model of the fuse, which is an element of the circuit, is described. Furthermore, the simulation result of the proposed circuit using the fuse model is presented, and the method of determining the circuit constant based on the simulation result is demonstrated. Finally, by connecting a prototype circuit based on this study in parallel with series-connected diodes, we show that the main circuit current of 60 A flow continuously even when one of the diodes is open.