SU1403308A1 - Self-excited push-pull transistor inverter - Google Patents

Abstract

This invention relates to electrical engineering and can be used in transistor oscillators. The goal is to simplify the design. The device limits the "through current in the magnetizing winding of the transformer and improves the quality of the output voltage by eliminating pauses of its transformation. For this, both magnetic cores with different MDS and magnetisation are connected by two feedback windings so that each of them covers the cores in the opposite direction. The through-current mode in the circuit elements is eliminated by limiting the current surges into the collector circuits of the transistors. The feedback windings transport the electromotive force of such polarity that they provide a re-switching of the keys, 4 sludge.

Description

I The invention relates to electrical engineering can be used in secondary power supply systems and automatics M converting DC voltage to AC.

The purpose of the invention is to reinforce the device.

FIG. 1 shows the structure of the output transformer; in fig. 2 is an electrical transistor inverter circuit; in fig. 3 - timing diagrams of the magnetic flux in the cores and for example; - the winding of the feedback windings; in fig. 4 - Magnetization curves of core materials.

; FIG. 3-4 introduced the following values: Фз - magnetic fluxes of the L cores; t is time; Uoc voltage on the feedback winding; In - induk-Qi.

: A transistor inverter (Figs. 1, 2) holds the output transformer 1, on the Core 2 and 3 of which one and the primary windings 4 and 5 are wound, one ends of which have a common point and Connected to the positive terminal of the source Ed, the negative terminal, which is connected to one power electrodes of transistors 6 and 7, to the other. power electrodes of which are connected the second ends of windings 4 and 5. The feedback windings 8 and 9 are connected by one ends through current-limiting resistors 10 And 11 to the base transitions of transistors, and the other ends - to the minus Conclusion 1 food waste. Each winding consists of two parts, wound on the core 2 and 3, respectively, and connected in succession sequentially relative to each other.

i The transistor inverter operates as follows.

I Let the initial state of the cores of the magnetic conductor correspond to B (Fig. 4). switching on the supply voltage due to the identical parameters, one of the transistors, for example 6, begins to open and its collector current increases to the magnitude of the alternating current of the core with a smaller MDS — working core 2. On all windings of the transformer, the induced EMF corresponds to the polarity shown in FIG. 2. Feedback windings 8 and 9 are connected so that

ten

15

20

25

thirty

torus 7. The inductive resistance of the feedback windings from magnetizing the core 2 is practically absent, since the core 2 does not peremagnetize (), where F-C is the MDS of the magnetization reversal of the corresponding core.

The decrease in the feedback voltage starts from the moment the core 2 begins to saturate.

In this case, the transistor 6 is still not closed due to its inertia and passes a current that tends to increase to the value of the short circuit current (since core 2 is saturated). However, the latter is limited by the magnetic field reversal current of the core 2. Almost instantly with the beginning of the magnetic reversal of the core 2, a reverse sign EMF is induced on the feedback windings, closing the transistor 6 and opening the transistor 7. The inductive resistance of the feedback winding from magnetizing the core 2 is almost zero and does not affect Neither the transistor control current. With the opening of the transistor 7, the magnetization reversal occurs in the other direction, i.e. a different half-period of voltage is formed. Now, a locking voltage pulse is applied to the base of the previously open transistor 6, and an even more opening pulse to the base of the closed 7.

Claims (2)

Invention Formula 35 A self-induced push-pull transistor inverter containing transistors and an output transformer, the magnetic conductor of which is made on two closed cores having significantly different magneto-magnetizing forces, both cores covered by primary and secondary windings, while the core with a small magneto-motive force is magnetized 40 swarm positive feedback windings, a core with a large magnetomotive force is gripped by a pair of negative feedback windings, and windings of inverse communication included in the input circuit of the corresponding arm of inverter transistors, characterized in that, for the purpose of simplicity, each winding of the positive feedback-connected oppositely in series with a respective winding O1ritsatelnoy feedback and connected through bazo45 the EMF induced in them is a fully open resistor to the input of the corresponding lOQuT-t g O1gO1L1 T g g f- I.I nniynr. , chg, JU Т Гчпт1П11-т / 1Гч: 1 transistor 6 and closes the transistor. 0 five 0 five 0 torus 7. The inductive resistance of the feedback windings from magnetizing the core 2 is practically absent, since the core 2 does not peremagnetize (), where F-C is the MDS of the magnetization reversal of the corresponding core. The decrease in the feedback voltage starts from the moment the core 2 begins to saturate. In this case, the transistor 6 is still not closed due to its inertia and passes a current that tends to increase to the value of the short circuit current (since core 2 is saturated). However, the latter is limited by the current of magnetic reversal of the core. 2. Almost instantaneously with the onset of magnetization reversal of the core 2, a reverse voltage EMF is induced on the feedback windings, covering the transistor 6 and opening the transistor 7. The inductive resistance of the feedback winding from magnetizing the core 2 is almost zero and does not affect the transistor control current. With the opening of the transistor 7, the magnetization reversal occurs in the other direction, i.e. a different half-period of voltage is formed. Now, a locking voltage pulse is applied to the base of the previously open transistor 6, and an even more opening pulse to the base of the closed 7. Invention Formula five A self-induced push-pull transistor inverter containing transistors and an output transformer, the magnetic conductor of which is made on two closed cores having significantly different magneto-magnetizing forces, both cores covered by primary and secondary windings, while the core with a small magneto-motive force is magnetized 0, the positive feedback windings, the core with a large magnetomotive force is engulfed by a pair of negative feedback windings, and the windings are about brotherly connection is included in the input circuit of the transistors of the corresponding inverter arm, characterized in that, for the sake of simplicity, each positive feedback winding is connected anti-sequentially to the corresponding negative feedback winding and connected through the base 5  T GCHpt1P11- t / 1Gch: 1 transistor. fie. d .g at