SU1282295A1 - Two-step transistor inverter - Google Patents

Abstract

The invention relates to the field of electrical engineering, in particular, to voltage-to-voltage converters from constant to alternating, and can be used in secondary power supply sources. The purpose of the invention is to increase the efficiency of the inverter by eliminating the asymmetry of the output signal that occurs when the transformer is magnetized. A two-stroke inverter containing an output transformer 1 and an electromagnetic switching element made in the form of a transformer 5 with a saturable core is provided with additional windings 4 and 6 located on the cores of transformers 1 and 5, respectively, orthogonal to the primary windings. The terminals of the additional windings 4, 6 are connected in series and connected to a variable voltage source. 4 il. (L

Description

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The invention relates to electrical equipment, in particular, to voltage transformers from a constant value in an electric circuit, and can be applied to electronic power sources of various devices.

The aim of the invention is to increase the efficiency of a push-pull transistor inverter by eliminating the asymmetry of the output signal that occurs when the transformer is remagnetized.

Ia Fig, 1-3. Depicts the circuit options push-pull transistor inverter; in fig. 4 is a magnetization diagram of a transformer core with orthogonal windings.

One of the variants of the two-sided inverter (FIG. 1) contains an output transformer 1, on the core of which the primary 2 is located, the secondary 3 and additional 4 windings orthogonal to HIM are electromagnetic switching element, ia is an example of transformer C 5 with gripping heart , additional about-. the coil 6 of which is orthogonal to the windings. 7 and 8, controllable keys 9 and 10 of the power amplifier and the master oscillator, are limiting 11. Controllable keys 10 and windings 7 of the saturating transformer 5 are connected according to the .inverter circuit with self-oscillation of the autogenerator. The keys 9, the winding 2 of the output transformer 1 and the winding 8 of the transformer 5 are connected according to the two-power amplifier circuit with a common emitter. Resistors 1 are included in the control electrode circuits of switches 9 and 10. The additional windings 4 and 6 of transformers 1 and 5, respectively, are connected to a sequence connected to an alternating voltage source whose frequency is equal to the frequency of the master oscillator.

With a lower output power, the inverter can be built according to the schemes shown in FIG. 2 and 3.

The embodiment of FIG. 2 contains an output transformer 1, a transformer 5 with a saturation core, controlled keys 9, limiting resistors 11 and 12, a symmetric Zener diode 13. Transformer J, keys 9, resistor 11 and winding 8 of transformer 5 are connected according to a two-stroke power amplifier with a common emit

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ter. The winding 7 of the transformer 5 is connected via a parametric variable voltage regulator on elements i, 12, and 13 with the outermost leads of winding 2 of the output transformer 1. In addition, windings 4 and 6 of transformers 1 and 5 are connected in series and connected to an alternating voltage source 14.

In addition to the transformer, the electromagnetic switching element can be made on the saturation throttle. An inverter circuit with a saturation throttle is shown in FIG. 3. This inverter contains controllable switches 9, an output transformer 1, resistors 11 and a saturation choke 15, on the core of which are located the base 16 and an additional orthogonal 6 windings. Elements 1, 9, and 1 are connected according to the two-stroke auto-generator scheme with combined manifolds. The main winding of saturation throttles 15 is connected between the control elec1c switches 9 and the windings 4 and 6 are connected, as in other variants.

A variant of the inverter according to the scheme of FIG. 1 operates in a similar way.

An oscillator on elements 5, 10, and 1 1 produces an alternating output voltage of a rectangular shape, and the duration of the pulses of each polarity is determined by the time during which the core is depleted; Pull one polarity to saturate another polarity. Typically, this voltage is a symmetrical meander. This voltage is applied to the control electrodes of the keys 9 of the power amplifier (elements 1, 9, 11, and c) and opens them alternately. In this case, a alternating voltage is applied to the winding 2 of the output- jHoro of the transformer 1, f

If the load connected to the winding 3 of the output transformer 1 is asymmetric with respect to the polarity of the output voltage (for example, it contains a half-wave rectifier) or the voltage applied to the winding 2 of the output transformer 1 is asymmetrical, like a difference in the recovery time of keys 9, the transformer core will be magnetized

also asymmetrically, the constant component of the bias current and the core at one of the polarities of the output voltage will begin to enter the saturation region.

The windings 4 and 6 of transformers 1 and 5 and the alternating voltage applied to them are selected from the following condition: in the absence of saturation of the core of transformer 1 in windings 2 and 3, it was not saturated in winding 4. Since the floor of the main 2 and 3 and additional 4 windings orthogonal, in the absence of the core, these windings do not affect each other. .

FIG. 4 to this case correspond to the magnetic flux from the winding 4 - varying along the B axis, and the magnetic flux from windings 2 and 3 - B, B varying along the B axis ... However,

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when, due to the asymmetry of the signal, the core of the transformer 1 enters the saturation region (Fig. 4), it is in saturation and for winding 4 (Fig. 4, B) a projection of the value of the saturation flux Bd deposited along the axis Bj on the axis B, . The voltage on the winding 4 decreases and the voltage and current of the winding 6 increase accordingly, which decreases the core induction saturation value of the transformer core 5, and the saturation of the core Ka of the transformer 5 means changing the polarity of the output voltage of the autogenerator and switching the control keys 9 of the amplifier power, so that when the core of the output transformer is saturated, 1 immediately closes the public key 9 and prevents the current from increasing. As a result, the decrease in the efficiency of a two-stroke inverter caused by the asymmetry of the output transformer signal is eliminated.

Similarly, the inverter works according to the scheme in FIG. A slight saturation of the core of transformer 1 causes saturation of the core of 5 transformer 5 transformer and the removal of

opening voltage control of the previously open control key 9.

In the inverter as shown in FIG. 3 the saturation of the core of the throttles 15 means the decrease of the inductive resistance of the winding 16 and also the removal of the opening voltage from the open

key 9. 5

Introduction to the output transformer and the electromagnetic switching element (transformer or saturation choke) of orthogonal windings connected in series to the alternating voltage source eliminates the asymmetry of the output transformer signal, which increases the efficiency of the device, the Invention Formula

Push-pull transistor inverter containing master oscillator,

0 made according to a circuit with an electromagnetic switching element, and a power amplifier with transistors with an output transformer, characterized in that

from increasing 1SD of the inverter by eliminating the asymmetry of the output signal that occurs when the transformer magnetizes, it is equipped with additional windings connected in series to the alternating voltage source, whose frequency is equal to the frequency of the master oscillator, and located on the cores of the electromagnetic switching element and the output transformer orthogonal. their primary windings.

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Claims (1)

Claim A push-pull transistor inverter containing a master oscillator made according to the scheme with an electromagnetic switching element and a power amplifier on transistors with an output transformer, characterized in that, in order to increase the inverter efficiency by eliminating the asymmetry of the output signal that occurs when the transformer is reversed, it is equipped with additional windings, connected in series, connected to an AC voltage source, the frequency of which is equal to the frequency of the master oscillator, and located and the electromagnetic cores of the switching element and output orthogonally transformer, their primary windings. Fig 2 Fig. 3 Fig. 4