FR2569914A1 - CONVERTER STABILIZED FOR CURRENT CONTINUOUS CURRENT POWER - Google Patents

Abstract

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

Description

The invention generally relates to current converter apparatus

  continuous AC and vice versa; it concerns more

  particularly converters that use

  rant to excite the primary windings of the transformer used to achieve this conversion.

  It is known in this field to periodically activate commu-

  such as silicon-modulated rectifiers in primary windings of transformers in order to obtain a voltage

  (and a current flow) of alternating phase in the windings sec-

  ondary. When the current requirements are not excessive,

  is known in the art of increasing the frequency with which converts

  can work. Higher frequencies allow the use of

  physically smaller components, such as condenses

  sateurs. However, when higher frequencies are used,

  effects are likely to become significant. For example, it is known in the art to use a common oscillator to control conduction

  through two switches (as well as through windings of trans-

  trainers associated with each switch). To prevent conduction

  simultaneous operation by both switches, which would result in

  excessive energy, an inverting element can be interposed between

  the oscillator and one of the switches. As the frequency increases

  the delay of the inverter element can cause conduction

  multaneous undesirable in both switches.

  It is an object of the present invention to provide a

  Advanced type energizer for transforming a current signal

  continuous into an AC signal.

  Another object of the invention is to provide for the use of two

  transistors for alternately introducing current into two windings

primary constituents.

  In addition, the object of the invention is to provide switches for alternately introducing current into primary windings.

  of a transformer, the apparatus designed in accordance with the present invention

  fishing simultaneous conduction through both switches.

  On the other hand, the particular object of the invention is to provide a third winding in the primary winding of a transformer, this third winding controlling the conduction of the current through one of the two transistor switching circuits so as to control the

  conduction of the current which feeds a transformer winding as-

  Socié. Finally, the invention also has the particular object of providing two transistor switching elements which alternately apply current to the two primary windings of a transformer, these elements

  in no case simultaneously conducting.

  These various objects of the invention, as well as others, are

  achieved through the adoption of a transformer with three

  in the primary winding system. The first and second rolls

  primary elements alternately introduce opposite phase current into the transformer. Control or adjustment of the current through each of these two windings is performed using a transistor switching device which is associated with each of these windings. The conduction of a first transistor switching device, and by

  conduction through an associated primary winding, is therefore

  uses a device designed to apply and delete alternatively

  an actuation signal to the control element (control terminal).

  latching) of the second transistor switching device. The trend

  in the third winding has the correct phase in order to

  conduction in the second trans-

  sistor during the interruption of current in the first primary winding

  mayor. The two transistors can not drive simultaneously.

  These different features of the invention, as well as

  very still, will emerge more clearly from reading the description

  which follows and refers to the Figures of the attached drawing, in which:

  FIG. 1 is a wiring diagram of a current-to-converter

  DC / AC current according to the invention, and

  FIGURE 2 is a timing diagram showing the trends

  used in the present invention.

  If we first refer to Figure 1, we can see that the

  5 and 6 are the input terminals for a DC voltage, terminal 5 is connected to a positive input voltage source while terminal 6 is connected to a negative input voltage source (relative to

  at terminal 5). Terminal 5 is connected by means of a condensa-

  14 to terminal 6; on the other hand, the terminal 5 is connected to a first terminal of a resistor 11 and to a terminal common to two main primary windings 33 and 34. The second terminal of the resistor 11 is

  connected to terminals 14, 4, 5 and 6 of a multivibrator 10 (4047B) and to

  to another capacitor 15 at the input terminal 6. The terminal 3 of the multi-

  vibrator 10 is connected through the resistor 14 to the terminal 2 of the multi-

  vibrator 10 and through a capacitor 13 to terminal 1 of the multivibrator

2A.69914

  The terminals 7, 8, 9 and 12 of the multivibrator 10 are connected to the input terminal 6, which is connected on the one hand to a source terminal of a MOS transistor (metal semiconductor). -oxide) 20, and secondly to

  a source terminal of a MOS transistor 21, and also, through a first

  primary winding 32 of the transformer 30, to a trip terminal of the transistor 21, the calibrated polarity of the first primary winding 32 being applied to this trigger terminal. The collector of the transistor 21 is connected through a second primary winding 33 to the common terminal 31, the calibrated polarity of this second winding

  33 is applied to said common terminal 31. The trigger terminal

  The transistor 20 is connected to the terminal 11 of the multivibrator 10, while the collector of the transistor 20 is connected through a third primary winding 34 of the transformer 20 to the common terminal 31, the calibrated polarity of the third primary winding 34 of the transformer being applied to the collector of transistor 20. The output terminals of

  voltages produced in the secondary windings 37 and 38 of the transformer

  The output terminal 51 is the positive terminal, while the output terminal 52 is the common terminal and the output terminal 53 is the negative terminal. The output terminal 52 is connected through a capacitor 45 to the terminal 51, and through another capacitor 46 to the terminal 53, the same output terminal 52 being connected to the secondary windings 37 and 38 of the transformer 30 through a terminal 39. The calibrated polarity of the secondary winding 38 is applied to the terminal 39. The second terminal of the secondary winding 38 of the transformer is connected to the cathode of a diode 44 and to the anode of a diode 42 The second terminal of the secondary winding 37, which is the calibrated polarity terminal, is connected to the anode of a diode 41 and to the cathode of another diode 43. The anode of the diode 41 and the anode of the diode 42 are connected to a terminal 51, while the cathode of the diode 44 and the cathode of the diode 43 are connected to a terminal 53. Whereas the converter is designed to operate at a relatively low frequency

  high, the transformer 30 is shielded. Standard values for

  For the resistance 11 and the resistor 14, 22 pf for the capacitor 13, 0.01 pF for the capacitor 15, and 0.33 FF for the capacitor 14, the values are 6.8 K-ohms.

  are a frequency of 600 Khz and an input voltage of 15 volts.

  Referring to Figure 2, ideal waveforms are

  for the current conducted through the transistors 20 and 21 in the ab-

  any load, as shown by the idealized waveforms for tripping voltages of the associated transistors. The tripping voltage of the transistor 20 can vary, in a particular mode of operation, between 0 and 6 V, while the tripping voltage

  of transistor 21 can vary between -6V and + 6V.

S Operation

  If we go back to Figure 1, we can see that the multi-

  vibrator 10 is designed to act as an oscillator to apply a

  gnal from terminal 11 to the transistor trip terminal

  during a specified period. The oscillator then removes the

  which excites or turns on transistor 20, generally during the same period of time. During the activation period of the transistor 20, the current flows through the primary winding 34 between the terminal 5 and the terminal 6. While the current flows through the primary winding 34, a voltage is induced in the other primary winding 32. The polarity of the voltage induced in the winding 32 maintains the

  transistor 21 in its non-conductive state. When the activation signal

  tion is removed from the trip terminal of transistor 20 and that

  it becomes therefore non-conductive, the current passing through the

  primary bearing is interrupted and a reverse electromotive force is

  generated, resulting in a change of polarity in the applied signal.

  than the tripping terminal of transistor 21. This change of polarity

  rity makes the transistor 21 conductive. The current then flows through the winding 33 and determines a change of direction of flow of the

  current in the primary windings while maintaining the conductive

  transistor 21 by virtue of the voltage induced in the winding 32.

  The transistor 21 remains in this conductive state until the instant when the activation signal is applied to the transistor 20, and the circulation of

  current through the primary winding 34 induces a voltage across the

  bearing 32, which puts the transistor 21 in a non-conductive state.

  It can therefore be seen that the conduction through the transistor 21 is determined by the non-conduction through the transistor 20 and

  that the simultaneous actuation of the two transistors is made impossible.

  The elements 41, 42, 43 and 44 provide a full rectification of the transformer signal 30 to provide DC power between the output terminals 51 and 53. It is evident that the current conversion

  AC current can be ensured by eliminating the

straighteners.

  The invention can function to maintain a magnetic flux

  than zero in the transformer core. This phenomenon results in the equalization of the utilization coefficients of each transistor in the case of small excursions with respect to equal coefficients of use.

  transistors. In case of slight imbalances in the coefficient of

  The flow will flow through the transformer core and this will result in an initial change in conduction in the transistors.

  The foregoing description is intended to illustrate the mode of

  operation of the preferred embodiment of the invention without any

  time limit the area of it. From this disclosure, it is apparent to those skilled in the art that various modifications and variations may be made in the practice of the invention without

  however depart from the basic principles of it.

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R E V E N D I A T IONS

  1. Apparatus for converting a DC voltage into a voltage

  a type comprising a transformer (30) composed of a first (32), a second (33) and a third primary winding (34), the latter being the control winding, characterized in that that he understands:

  a) first switching means (20) connected to the first

  primary bearing (32) to establish a magnetic flux in the core of the transformer (30), and

  b) second switching means (21) connected to the second winding

  (33) to establish a magnetic flux in said transformer core, the primary control winding (34) driving the

  second switching means (21) when a pre-determined value stream

  determined exists in the transformer core.

  2. DC / AC power converter device according to

Claims (17)

Claim 1, characterized in that the first switching means comprises a first transistor (20) connected in series between the DC voltage source and the first primary winding (32).   3. DC / AC converter device according to either   Claims 1 or 2, characterized in that the second means of   switching comprises a second transistor (21) connected between the second primary winding (33) and the DC voltage source, an element   controlling the second transistor (21) being connected to the primary winding   control mayor (32) of the transformer (30).   4. DC / AC converter apparatus according to any one of the   1 to 3, characterized in that the first and second switching means (20, 21) are activated for periods substantially   equal to one cycle, the magnetic flux of the transformer core these cycle periods.   Converter apparatus according to any one of the claims   1 to 4, characterized in that the magnetic flux of the core of the trans-   trainer establishes a condition of balance during periods of   by the first switching means (20) and the second means switching (21).   Converter apparatus according to Claim 1, characterized in that: a) the first switching means (20) applies the current to the transformer (30) during a first period of a cycle; b) the second switching means (21) applies current 69914   -7- to said transformer (30) for a second period of said cycle, and   c) the control means (10) actuates the second means of com-   mutation (21) while the first switching means (20) is inactive.   7. DC / AC converter apparatus according to Claim 6, characterized   rised by the fact that said first period of the cycle and said second   period of the cycle are in equilibrium relation between them.   8. DC / AC converter apparatus according to Claim 1, characterized rised by the fact that it includes:   a) said transformer (30) which comprises a winding se-   o10 condaire (37, 38); b) the first switching means (20) connected to the primary winding (32) of the transformer (30) for periodically conducting the current through the first primary winding (32), and   c) the second switching means (21) connected to the second winding   (33) as well as control winding (34) in order to   conduct current conduction through the second primary winding   mayor (33) when the first switching means (20) does not conduct the current.   9. DC / AC converter apparatus according to Claim 8, characterized   in that the first switching means (20) comprises a   oscillator (10) and a first transistor (20) -.   10. DC / AC converter apparatus according to any one of   8 or 9, characterized in that the second device of   switching comprises a second transistor (21), that the conduction of the   through this second transistor is controlled by a voltage   from said control winding (34) connected to a control element of the second transistor (21).   11. DC / AC converter apparatus according to any one of the   Claims 8 to 10, characterized in that the voltage across said secondary winding (37, 38) is a high frequency alternating voltage.   12. DC / AC converter apparatus according to any one of   8 to 11, characterized in that a period of   controlled by said first switching means (20) and that a   conduction period controlled by said second switching means (21) reach a state of equilibrium.   Converter apparatus according to Claim 1, characterized in that: a) said transformer (30) comprises a third primary winding (34);   b) there is provided a first transistor (20) connected to said first   primary winding (32) for controlling current conduction through said first winding (32) during a first portion of a cycle; c) the apparatus comprises a signal generator (10) for driving the first transistor (20), and d) a second transistor (21) connected to the second winding (33), the second transistor (21) controlling the conduction of the current to   through this second winding, this same second transistor (21) being   connected to the third winding (34) which makes the second transistor {21)   during a second part of said cycle.   Converter apparatus according to Claim 13, characterized   in that the transistors (20, 21) are semiconductor elements   metal oxide, said third winding (34) being connected between   a trigger terminal and a source terminal of said second transistor tor (21).   15. Converter apparatus according to any one of the   13 and 14, characterized by the fact that the third winding   (34) is connected directly between a trip terminal and a terminal   a source of said second transistor (21).   16. Converter apparatus according to any one of the   13 to 15, characterized in that the signal generator is a multivibrator (10).   17. Converter apparatus according to any one of the   13 to 16, characterized in that said transformer (30) provides a high frequency alternating output current across   its secondary windings (37, 38).   18. Converter apparatus according to any one of the   13 to 17, characterized in that the first cycle part and   the second cycle part are in equilibrium relation between them.   19. Process for converting a DC voltage into a voltage   A method according to Claim 1, characterized in that it comprises the steps of: a) activating a first switching means (20) by flowing current through said first primary winding (32) of said transformer ( 30) during a first part of the cycle; b) deactivating this first switching means (20) at the end of said first part of the cycle, this deactivation being translated 2 969914 -9   by generating a control signal in said primary winding   control mayor (34) of said transformer (30), and c) activating a second switching means (21) with said control signal to conduct current in said second primary winding (33) of said transformer (30). ).