Circuit for controlling the switching frequency of scr regulators

Abstract

A control apparatus for a switching regulator circuit having a voltage controlled oscillator responsive to any deviation of the output voltage of the switching regulator circuit from a predetermined reference voltage. The voltage controlled oscillator produces a digital pulse stream having a frequency which is varied by the voltage controlled oscillator in response to any deviation of the output voltage of the switching regulator circuit from the predetermined reference voltage. A recovery detector is connected to at least one of the reactors of the switching regulator circuit to ensure that the particular SCR associated with that reactor has fully recovered prior to the next actuation thereof. If the particular SCR has not recovered then the digital pulse which would be distributed to that SCR within the digital pulse stream is held. The digital pulse stream is received from the recovery detector by a maximum frequency detector, which prevents the digital pulse stream from exceeding a predetermined maximum frequency. The output of the maximum frequency detector is received by the SCR sequencer which distributes the individual pulses within the digital pulse stream in a known sequence to the switching regulator circuit for actuation of the individual SCRs therein.