A triple redundant controller which adopts the time-sharing fault recovery method and its application to a power converter controller

A novel fault recovery method, in which memory copy from a normal system to a fault detected system is executed in time-sharing fashion, has been implemented in a triple redundant controller. This method reduces data copy bandwidth required for recovery of the fault detected system, and allows non-stop fault recovery with only a little hardware overhead, even when the controller contains multiple processors and operates at a very short operating period. The developed controller contains triplicated processing units, each of which consists of seven 60 MIPS processor boards connected by a 30 MHz 4 byte bus. One processor board contains a bus arbiter, and each of the remaining six processor boards contains three sets of 100 Mbps two-way optical links, which can be utilized for inter-system memory copy as well as for connecting to 10 units. This controller has been applied to a power converter controller, and a 104 microsecond operating period was achieved.