Booster (electric Power)
A Booster was a motor-generator (MG) set used for voltage regulation in direct current (DC) electrical power circuits. The development of alternating current and solid-state devices has rendered it obsolete. Boosters were made in various configurations to suit different applications.
Read more about Booster (electric Power): Line Booster, Milking Booster, Reversible Booster, Metadyne