AC voltage regulator - has staged transformer with triac switching stages controlled by solid stage shift registers

摘要

The a.c. voltage regulator is designed to be unaffected by changes of the mains frequency and the power factor of the coupled load. The mains supply is coupled (2,3) to the primary winding of a transformer (1) that has two groups (41,42), each of eight, pick-offs. Each pick-off is coupled to a triac switching stage and allows a total of 64 voltage levels to be selected e.g. regulated output from 180 to 244 volts in 1 volt stages. The triac firing is controlled by two eight stage shift registers (91,92) that respond to the output voltage (61,62) using a voltage discriminator (95), analogue to digital converter and logic stage (96).