Their main purpose of VSDs is to reduce the amount of energy and electricity consumption, which they can do without changing motor speed. They can help save energy in plants that use powerful electric motors, as well as operating other areas such as sewage and irrigation pumps, paper machines, sawmill conveyors and hospital ventilation systems.

Drives are available in various different sizes to suit the size of the motors they are regulating. They are also known by several other names including adjustable speed drives, variable frequency drives, AC drives and inverter drives. Since being introduced to the market, they have overtaken DC motors and controllers to become the most popular and cost-effective motor control system.