Cool facts about cooling electric motors

The evolution of electric motor design, as it pertains to cooling methods, provides insights about better ways to cool machines in service. The array of methods engineers have devised to solve the same problems is fascinating yet reassuring, because many things remain unchanged even after a century of progress. This paper discusses how motors are cooled and how heat dissipation can be improved for applications that fall outside the “normal operating conditions” defined by NEMA Stds. MG 1-2011 [1].