A novel combination of permanent magnet generator and exciter

Brushless standby generator sets require an auxiliary excitation support system to provide fault clearing capabilities. Generator sets are typically required to carry 300% fault current for ten seconds. Fault current is required to trip breakers and clear devices from the generator set. The most popular auxiliary excitation method for standby generator sets is provided by a rotating exciter and permanent magnet generator (PMG). The PMG and traditionally been considered two separate machines. Each machine requires materials, machining and room on the interior and/or exterior of the main generator shell. This requires additional cost for each generator with a PMG. A new machine is introduced that combines the functionality of both machines into a single structure. The combination machine is called a PMG exciter (PMEX). The PMEX is made in such a way that unwanted interaction of the two devices is kept to a minimum. This device reduces the overall machine length and reduces generator manufacturing complexity. Due to minimal interaction of the two devices combined in the PMEX, the device was analyzed in a traditional manner as two separate machines