Current regulation of rectified A.C. supply - uses anti-parallel thyristors or rectifier bridge between A.C. supply and D.C. load

摘要

The current regulator for both d.c. and a.c. loads samples the a.c. supply to obtain a reference current and an actual value current which are then used to control the thyristors regulating the current. For a.c. loads two anti-parallel thyristors (2) are connected between one supply terminal and one load terminal and are controlled (3), depending on the reference value derived from the supply fundamental frequency. the actual value signal is taken from the a.c. supply side of the thyristors. For d.c. loads the a.c. supply is rectified by a diode bridge (7) whose output is coupled over a single thyristor (2a) to the d.c. load. The actual value signal is obtained from the load.