GB1000512A - Inverter - Google Patents

Abstract

1,000,512. Controlled non-linear inductors. CESKOSLOVENSKA AKADEMIE VED NO. 3. Sept. 19, 1961, No. 33471/61. Heading H3B. A magnetic complementing amplifier comprises a core 3 having a rectangular hysteresis loop and associated control and output windings 2, 6, the control winding being connected between earth and an alternating potential 5 through diodes 7 and 10, and the diodes being biased in the conductive direction by a negative potential 8 applied over resistors 9, 11 to such an extent that both diodes are conductive when a normal switching current is passed through winding 6, and one diode becomes cut-off if the winding current exceeds the normal value. The diode which is cut off depends on the direction of the excessive winding current. For operation as a logical device, winding 2 is either effectively short circuited or open circuited at control terminal 1. With an open circuit at terminal 1 (or the equivalent in the form of a high control potential), the core flux changes between positive saturation (set) and negative saturation (reset) in correspondence with the positive and negative half cycles of the alternating potential. In each case current flows between 5 and earth through the diodes 7 and 10 in the appropriate direction. The negative half cycle periods are used to apply control signals and the positive half cycle periods are used to derive a complementing output at terminal 4. With the control winding open-circuited the voltage between terminal 4 and earth through conductive diode 10 is zero in the output period immediately following the control period. If the control winding is short-circuited in a control period the induced current from winding 6 to winding 2 prevents the core flux from being set to positive saturation. Due to the negligible voltage drop across winding 6, diode 7 is no longer negatively biased and becomes cut-off. In the following output period, since the core has not been reset flux switching cannot take place. Consequently the negligible voltage drop of winding 6 changes the bias of diode 10 which is cut-off. An output voltage therefore appears at terminal 4. In a modification, Fig. 2, resistors 9 and 11 are combined in a single resistor 12 by the use of a tap 13 on winding 6. Logical input gates are provided in association with winding 2 which cause the amplifier to provide a complementing output if appropriate terminals 22-27 are energized, and a direct output in response to appropriate energization of terminals 28-30.