SU1684912A1 - Push-pull blocking oscillator - Google Patents

Abstract

The invention relates to a pulse technique and can be used to generate pulses in various radio installations. The purpose of the invention is to increase reliability and efficiency. The block generator contains switching transistors 1, 2 connected by input and output circuits to transformer windings 3, starting generator 4, diode 5. The inductance is controlled as an additional winding 6 located on the core of the transformer 3 orthogonal to the main windings , is connected between the common power supply bus and the emitters of the switching transistors 1, 2. which stabilizes the load current. 1 silt

Description

The invention relates to a pulse shaper and can be used in various electronic devices.

The purpose of the invention is to increase reliability and efficiency by stabilizing the load current.

The drawing shows a schematic diagram of the blocking generator.

The blocking generator contains switching transistors 1, 2 connected by input and output circuits to the windings of transformer 3, a starting generator 4 and a diode 5. The control inductance, made in the form of an additional winding 6 located on the core of the transformer 3 is orthogonal to the main windings, connected between the common power bus and the emitters of the switching transistors 1 and 2, to which the output of the starter generator 4 and one of the terminals of the diode 5 are connected, the other terminal of which is connected to the common power bus.

The blocking generator operates as follows.

In the initial state, the magnetic circuit of the transformer 3 is demagnetized and the operating point in the directions of magnetization is located at the coordinates (0; Br). When a blocking generator is connected to a constant voltage source, the starting generator 4 generates a triggering energy-intensive pulse. Since the output of the starting generator 4 is connected to the additional winding 6, the inductance of this winding begins to accumulate the energy of the trigger pulse. In this position, in the absence of currents through the switching transistors 1, 2, the inductance of the additional winding 6 has the maximum value (since / g // max, where // is the magnetic permeability of the winding material). After pumping the energy of the starting img.ulse B inductance of the additional winding 6, the polarity of the voltage is changed

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on the additional winding 6, with the voltage across it being limited by the Unp value of the diode 5. A positive voltage from the auxiliary circuit 6 is applied to the control inputs of the switching transistors 1.2. The transistors open and, due to the inevitable difference in the characteristics of the transistors, a blocking process begins to develop. Moreover, due to the initial significant inductance of the additional winding, the load on the transformer windings does not affect the development of the blocking process, and when the load decreases (for example, a capacitive load is the worst case), the reduced resistance in the basic circuits decreases, which increases the transfer of positive potential. ala in the additional winding 6, and therefore improves the launch. The blocking process is associated with the occurrence of voltages on the windings and, therefore, the appearance of the load current. The additional load current and the linearly varying magnetization current of the primary winding If flows through the additional winding 6. These currents flow through the primary winding and reduce the inductance of the additional winding 6 at times of increasing iu, i.e. with saturation of the transformer core and switching of the block generator. This is necessary so that at a constant, practically reduced load current, the inductance value of the additional winding 6 is somewhat larger and provides current stabilization (for example, when operating on a rectifier with a capacitive filter, which, after switching, produces a current surge that is required for yes capacitance), and with saturation of the core and an increase of 1, the inductance dropped sharply, but due to the significant current 1 would form a voltage by a nonlinear communication winding to lock the previously open transistor, i.e. the blocking process proceeds in two directions: by increasing (the transistor leaves the saturation mode (in this case, not the main mode)), by increasing L, the voltage on the inductance of the additional winding 6 arises, which allows to form the switching process. the number of turns of the additional winding b, you can set the switching current 1 ..

Since the windings are not orthogonal, they are not alternating voltages from each other, and the quadrature induction transforms provide complete circuit symmetry (Bs2 Вх2 + Vу2, where Bs is the induction of saturation of the transformer core. Vh. - induction in magnetization directions main and additional windings). With a short circuit, the current through the main and additional windings 6 increases, which leads to a sharp increase in frequency and

With the generation stall, the additional effect of increasing the frequency makes it possible to increase reliability, since with short impulse loads, the permissible pulsed power for transistors increases. When the device operates, the start-up circuit does not affect, and the inductance of the additional winding 6 stabilizes the load current. Transformer 3 with main and additional winding 6 is most easily performed on

crossed fields (on the cup core mutually perpendicular windings are made, and the cores are inside the core, and on top, additional cores are used through the core). Thus, it is assured

Claims (1)

running, increasing efficiency and improving the switching modes of the transistors. Claims of the invention Push-pull blocking generator comprising two switching transistors, the collectors of which are connected to the power bus through the corresponding collector windings of the transformer; and a common bus, characterized in that, in order to increase efficiency and reliability, the controlled inductance is made in the form Flax transformer winding, located on its core orthogonal to the main windings.