Regenerative braking in slip-power-recovery systems

The basic theory of solid-state slip-power-recovery systems is now well established. One of the disadvantages of such systems has been the lack of a suitable method of regenerative braking: this is frequently an important requirement for many applications. The paper describes two methods of incoporating regenerative braking in slip-power-recovery systems. One method requires a separate source of direct current and is called the `separately excited¿ regenerative brake; the second method employs direct current from the d.c. link in the system and is called the self-excited system. Both systems are shown to be practicable and capable of operation down to speeds of at least 0.05 p.u.