SU725190A2 - Power transistor control device - Google Patents

Description

one

The invention relates to electrical engineering, and can be used in the construction of pulsed stabilizers, transistor inverters, and other devices that use power switches.

According to the main author. St. No. 574845, a device for controlling a power transistor, comprising two mid-point transformers, the primary windings of which are connected to two sources of phase-shifted at an adjustable angle of rectangular voltage, the output terminals and two transistors, the base-emitter junction of which bypasses the secondary windings of one of the transformers with a midpoint connected to the first output terminal of the device, and the second output terminal of the device is connected to the middle, the output of the secondary windings of another transformer, on chennyh into the collector circuit of said transistor.

The aim of the invention is to increase efficiency. For this, the proposed device is additionally equipped with two resistors and two transistors, each of which is connected to the collector by an emitter, and the main transistor emitter to the emitter, additional transistors npHtieM bases through additional resistors to the connection points of the corresponding transformer.

The drawing shows a diagram of this device.

The device for controlling the power transistor contains two transformers 1, 2 with a midpoint, the primary windings of which are connected to two sources that are out of phase at an adjustable angle to the right side of the HI. The ends of the secondary winding of the transformer 1 are connected to the collectors of the main 3 and 4 and additional 5 emitters; and 6 transistors, and its middle point is connected to output terminal 7. The ends of the secondary winding of transformer 2 are connected through main 8 and 9 and additional 10 and 11 resistors to bases of main 3 and 4 and additional 5 and 6 transistors, and its middle point is connected to emitters of main 3 and 4 and collectors of additional 5 and 6 transistors and to the output terminal 12. The device operates as follows.

Claims (1)

Suppose that the beginnings of the secondary windings of transformers 1 and 2 (indicated by a dot in the drawing) correspond to the polarity of the voltage. In this case, the transistors 4 and b are open, and the transistors 3 and 5 are locked. The locking mode is provided by selecting the voltage on the secondary winding of the transformer 2, which should not be less than twice the voltage on the winding of transformer 1. Through the normally open 6 and inversely open 4 transistors, the output terminal receives a minus power source, and the base current of the power transistor in this case, it is provided by two transistors, in which the base currents are equal, and the collector ones are distributed in proportion to the ratio of normal BN and inverse Bj gain factors. 15 When the voltage on the secondary winding of transformer 2 is changed, transistors 4 and 6 are closed, and transistors 3 and 5 are unlocked, ensuring the change of polarity of voltage at output terminals 20 and 7 and 12. Once again, the base current of the power transistor is provided by one normally open 3 and one inversely open 5 transistors. After changing the polarity of the voltage on the winding 5 of transformer 1, the processes are repeated with the difference that in normal mode, in this case, depending on the polarity of the voltage on the winding of transformer 2, transistors 4 and 5 will work, and in iy-30 version - transistors 3 and 6. Thus, by changing the phase 10 of two initial rectangular symmetric voltages, a bi-polar unbalanced voltage is obtained at the output of the device, the filling factor of which is g - (where 1 is the duration of the positive voltage and load, T - pulse period) can vary from 0 to 1 in accordance with the phase changes, and in the saturation mode and in the mode of dissipation of the excess charge the formation of the base current of the power transistor involves a normally open transistor, which makes it possible to significantly reduce power costs in the transistor control circuit and increase device efficiency. The invention The device for controlling a power transistor according to the author. St. N ° 574845, characterized in that, in order to increase efficiency, it is equipped with an additional two resistors and two transistors, each of which is connected to a collector by an emitter, and to the emitter of main transistors by a collector, and additional resistors are connected to additional connection points main resistors with a secondary corresponding transformer winding torus lg