Efficiency improvement in redundant power systems by means of thermal load sharing

The demand for higher output currents at ever lower voltage levels is often solved by paralleling multiple converters. Provided redundancy is implemented this technique, besides being relatively easy to implement, has the advantage of improving the overall system reliability. Also, the parallel-connection concept forms the basis of a very cost-effective power system design, since the entire system often can be realized using off-the-shelf units. This paper verifies experimentally that the use of the thermal load sharing technique, not only increases the overall system reliability but also has a positive impact on the system efficiency. The latter aspect is achieved by redistributing the current throughput of each converter, which in turn results in equal thermal conditions as opposed to the current sharing technique´s intent to establish equal currents.