High power regulated D.C. supply

• US 3,922,595 A
• Filed: 05/23/1973
• Issued: 11/25/1975
• Est. Priority Date: 05/23/1973
• Status: Expired due to Term

• Current Assignee: Bruno John Vieri
• Original Assignee: Bruno John Vieri
• Inventors: Vieri, Bruno John
• Primary Examiner(s): Envall, Jr., R. N.
• Application Number:
  US05/363,457
• Time in Patent Office: 916 Days
• Field of Search: 321/15,16,18,47
• US Class Current: 363/54
• CPC Class Codes: H02H 7/12 for static converters or rectifiers for discharge lamp power supplies using static converters H05B41/2851, H05B41/2921, H05B41/2981
• CPC Class Codes: H02M 7/1555 with control circuit
• CPC Class Codes: H02M 7/1557 with automatic control of the output voltage or current

Abstract

A regulated AC to DC converter includes a pair of controlled gates which are triggered into conduction selectively during the positive and negative half cycles of the alternating current. An improved triggering circuit is provided which includes a monostable multi-vibrator for providing a train of trigger pulses, circuitry for driving the multi-vibrator to generate the train of trigger pulses, circuitry for triggering the controlled gates into conducting states selectively in response to the trailing edges of the train of trigger pulses and circuitry for applying a control current to the multi-vibrator for controlling the time position of the trailing edges of the trigger pulses relative to the phase of the alternating current applied to the converting means, whereby the duration of conduction of the controlled gates in the corresponding half cycle of the alternating current is controlled.

Claims

1. In a regulated AC to DC converter including a pair of controlled rectifiers which are triggered into conduction selectively during the positive and negative half cycles of the alternating current, an imporved triggering means comprising:

a monostable multivibrator for providing a train of output pulses, means for driving said multivibrator to generate said train of output pulses in predetermined phase relation to the alternating current, means responsive to the trailing edges of said output pulses for providing a train of trigger pulses, means for actuating said controlled rectifiers into conducting states selectively in response to said train of trigger pulses, and means for providing a control current to said multi-vibrator for controlling the width of the output pulses so as to control the time position of the trigger pulses relative to the phase of the alternating current, whereby the duration of the conduction of the controlled rectifiers in the corresponding half cycle of the alternating current is controlled.

2. The converter according to claim 1, further including means for generating a train or reset pulses and applying said reset pulses to said multivibrator timed to occur at zero crossings of the alternating current.

3. The converter according to claim 1, wherein said means for driving said multivibrator includes:

means for phase-shifting the alternating current by 90*, means for detecting zero crossings of the phase-shifted alternating current and generating a train of set pulses occurring at the zero-crossings of the phase-shifted alternating current, and means for applying the train of set pulses to said monostable multivibrator to generate said output pulses.

4. The converter according to claim 3, wherein said zero crossing detecting means and set pulse generating means includes a limiter, pulse shaper and a negative logic OR gate connected in series.

5. The converter according to claim 1, further including means for deTecting an overload condition and generating an overload condition signal and means for disabling said multivibrator driving means in response to said overload condition signal, whereby the generation of the trigger pulses is prevented.

6. The converter according to claim 2, wherein said means for applying said train of set pulses to said monostable multivibrator includes a coincidence gate having a first input means to which said train of set pulses are applied and a second input means to which said overload condition signal is applied.

7. The converter according to claim 6, wherein said overload condition detection means is adapted to apply a logical 1 to said coincidence gate under no overload condition and apply a logical 0 as the overload condition signal to said coincidence gate under the overload condition.

8. The converter according to claim 7, wherein said overload condition detection means includes:

resistive means inserted in the DC output path and means for sensing the voltage drop across said resistive means exceeding a predetermined level, and a flip-flop being set to provide said logical 1 to said coincidence gate and being reset to provide said logical 0 to said coincidence gate in response to detection of the voltage exceeding said predetermined level.

9. The converter according to claim 1, wherein said control current providing means includes:

means for sensing the load voltage and generating a load voltage level signal, means for providing a predetermined reference voltage, means for comparing said load voltage level signal to said reference voltage and generating said control current, and means for applying said control current to said multi-vibrator.

10. The converter according to claim 4, further including a reset pulse generating means having a limiter and a differentiator connected in series and interposed between the alternating current source and said monostable multi-vibrator and adapted to generate a first train of negative going pulses occurring at the positive going zero crossings of the input alternating current and being applied to said monostable multi-vibrator to reset it positively into its stable state after it is switched into its metastable state and a second train of positive going pulses occurring at the negative going zero crossings of the input alternating current to set positively the multi-vibrator into its stable state, whereby said multi-vibrator is positively conditioned to receive each of said train of pulses from said means for driving said monostable multi-vibrator and generate said output pulses.