Ricerc@Sapienza

Nowadays there are 3 % of missed start-ups of emergency gensets in Italian hospitals every year. The subject of this work is the analysis of the failure to start an emergency genset due to the failure of the batteries. The work is based on ten years statistics of maintenance on hospital facilities. A real case study is here described; measurements were made on a 1000 kVA genset of a hospital to study the real operating conditions of the system. The whole electrical, mechanical and dynamic model of the starter system of a genset is studied. Computer simulations for this study are based on the Matlab/Simulink model of the considered starter system. An automatic system of parallel between the batteries of different generators is presented as a solution to the problem. This system can also indicate to the maintenance technician the need to replace a partially deteriorated battery in a timely manner. It is also proved that it is possible to succor the failed battery instantly without losing the first part of the starting transient. The work demonstrates that the failure to start, due to a fault in the batteries, can be significantly reduced by using the proposed solution. With this technical proposal the risk of blackouts and relative human losses are largely reduced.