SU847470A1 - Transistorized inverter - Google Patents

Description

(54) TRANSISTOR INVERTER

i

The invention relates to a technique for converting direct current energy into alternating current energy and can be used in devices for the secondary power supply of electronic equipment.

Transistor inverters are known, built according to the multivibrator circuit with a transformer positive feedback, in which to reduce losses, the transformer is made on cores made of a material with a high coefficient of hogresis loop rectangle.

The disadvantage of these inverters is that the operation of the circuit is accompanied by the appearance of pulses of a collector current of considerable and uncontrolled amplitude, which reduces the efficiency and reliability of the device.

The closest to the invention is a transistor inverter, two transistors and a main transformer with primary, secondary and feedback windings, connected by a middle point, with the middle points of the primary winding and the first and second transformer input terminals of the inverter, respectively, and the extreme leads of the feedback winding through the limiting resistors with the base transistors, an additional transformer with two primary windings, Connected in series with the power circuits of the respective transistors, with the secondary winding connected in series with the secondary winding of the main transformer and the additional winding f2J.

The disadvantages of the known inverter are the inadequate accuracy of fixing the moment of increasing the collector current, as well as tightening the cut-off front of the transistors due to the presence of scattering inductance between the primary and additional windings of the additional transformer, which reduces the reliability of the inverter. The purpose of the invention is to improve reliability by speeding up the process of turning on transistors. The goal is achieved by the fact that in a transistor inverter, an additional transformer is made on two cores with one primary winding on each, each primary winding of an additional transformer is connected between the emitter of the corresponding transistor and the second input terminal of the inverter, and the additional winding through the ballast resistor is between the first and second input terminals of the inverter, with additional winding included reen. but each primary winding is an additional transformer. The drawing shows a diagram of a transistor inverter. The inverter contains the main transformer 1 (; primary 2 and secondary 3 windings and feedback windings 4. The outputs of the primary winding 2 are connected to the collectors of transistors 5 and the emitters of which are connected to the middle point of the winding 4 of the reverse link through the primary windings 7 and 8 The terminals of which through resistors 10 and P are connected to the bases of transistors 5 and 6, In turn, the middle points of the primary winding 2 and feedback windings 4 are connected to the first 12 and second 13 terminals of the inverter, To the output terminals 14 and 15 of the inverter connected in series are the secondary windings 3 and 16 of the main 1 and additional transformers 9. An additional transformer 9 is made on two cores 17 and 18, and its additional, additional winding 19 is connected between the input terminals 13 and 14 via a ballast resistor on the cores of a material with a high rectangular hysteresis loop. The ratio of the number of turns of the primary 8 and the secondary 16 windings of the additional transformer is equal to the ratio of the turns of the primary 2 and secondary 3 windings of the base Nogo transformer. The secondary windings 16 of the additional transformer are connected successively with the secondary winding 3 of the main 8 04 transformer, and their inclusion with respect to the primary winding 7 of the auxiliary transformer (counter or consonant) must coincide with the inclusion of the secondary winding 3 of the main transformer relative to the primary winding 2 of the main transformer . The bias winding 19 of the auxiliary transformer must be turned on so that the magnetizing force of this winding is directed oppositely towards the magnetizing force of the primary winding 7 of the auxiliary transformer. With such switching on, the magnetizing force in the core of the additional transformer is defined as: where IXXOCH is the magnetizing current of the main transformer; -the base of the transistor; - magnetizing power of the winding XY, p of an additional transformer. The magnetizing force of the secondary winding 3 of the Additional Transformer is compensated for by the magnetizing force generated by the load current in the winding 7 brought to the winding 2 of the main transformer. The value of f is chosen so that during the magnetization reversal of the core of the main transformer the condition PC, O is maintained. when its core F is saturated, it becomes greater than O. The remagnetization of the core of the additional transformer begins and the corresponding trans hist under the influence of electromotive force occurring in the coil, is locked fast on the emitter circuit, a result achieved arbitrarily hard limit inrush current in the collector circuit of transistors, irrespective of the load transistor and the current transmission ratio (neglecting of instability). In addition, since the additional transformer is re-magnetized only at the moment of switching the circuit, the dimensions of its core are small. Such inclusion of an additional transformer is distinguished by the proposed transistor converter, for example

Claims (1)

Claim Transistor inverter comprising two transistors and a main transformer with a primary, a secondary winding and a feedback winding, ^z each of which is connected to the scheme with midpoint, and the midpoints of the primary winding and the feedback winding of the main transformer | ₅ tori are connected to the first and second input terminals of the inverter, respectively, and the extreme terminals of the feedback winding through the limiting resistors are connected to transistor bases, ₂ θ an additional transformer with two primary windings connected in series with the power circuits of the corresponding transistors, with a secondary winding connected in series 25 with a secondary winding of the main transformer and an additional winding, characterized in that, in order to increase reliability by accelerating the process of switching on transistor ov, the specified additional transformer is made on two servo ·: receivers with one primary winding on each, each primary winding of the additional transformer is connected between the emitter of the corresponding transistor and the second input terminal of the inverter, and the additional winding through the ballast resistor is between the first and second input terminals of the inverter moreover, an additional winding is included counter to each primary winding of an additional transformer.