Abstract: Power supply turn-on and turn-off transients are eliminated in power supplies employing thermionic vacuum tube pass devices and control amplifiers for controlling the output voltage of the power supply by controlling the conductance of the pass tube or tubes. The elimination of turn-on transients is accomplished by cutting off the pass tube and rendering the control amplifier non-responsive for a predetermined time after the power supply is turned on. The turn-off transients are eliminated by quickly restoring the cut-off of the pass tube and the non-responsive rendering means of the control amplifier very quickly after the turn-off instant of the power supply.

Abstract: A first low voltage power supply having silicon controlled rectifier regulation in the primary of the power transformer, capable of supplying very high direct current, and a second well regulated feedback power supply providing a fixed current in reverse polarity are connected in parallel across a load. The first power supply is feedback controlled to maintain constant current sinking in the second power supply. The second power supply is programmed to regulate the load current or voltage, to provide fine regulation at the load, and to reduce ripple voltage at the load.

Abstract: The power supply output is monitored by voltage and current mode amplifiers, which drive a shunt stabilizer according to control commands and load requirements, the shunt stabilizer altering its conduction, thereby compensating for any tendency of the output to change from its preset level. Simultaneously, the current through the shunt stabilizer is itself monitored by a control amplifier. Depending on the demands made on the shunt stabilizer (which in turn depends on the output requirements), the conduction angle of the control rectifiers in the silicon controlled rectifier phase control circuit are altered. The shunt stabilizer's current is thereby regulated. Two additional amplifiers are used to control the output current. One, the foldback amplifier, receives its input signals from the current mode amplifier and output terminals to transfer the power supply into foldback mode if an overload is present at the output terminals.

Abstract: Two sources of current are applied to a load. One source supplies a constant current which is at least equal to the maximum current to be supplied to the load in one polarity. The second source is in opposition to the first source and is capable of being controlled from zero to a value at least double the value of the constant current. A voltage feedback circuit in combination with a bipolar control signal provides a bipolar voltage across the load having maximum positive and negative voltage excursions equal to the control signal times the feedback circuit gain and current in either direction having a maximum value substantially equal to the constant current value. In this manner a high voltage regulated bipolar voltage can be controlled across a load using one controlled unipolar device while providing class A operation, that is, without cross-over distortion. An important feature of the invention is the positive and negative limiting of both load voltage and load current.

Abstract: In a high current shunt stabilized regulated power supply transients may occur containing too much energy for the shunt stabilizer to safely absorb. The absorber circuit is designed with capacity to absorb normally encountered transients. If the transient lasts longer than a predetermined interval a crow-bar circuit is activated and the power supply is shut down.