SU796830A1 - Ac stabilizer - Google Patents

Description

one

The invention relates to electrical engineering and can be used to power various automation devices and electrical equipment with stabilized current.

The AC regulator is known, which contains a voltage inverter and a linear choke in the inverter AC circuit 1

The closest to the proposed is the AC power regulator, which contains an inverter with zero output of the transformer primary winding on two key transistors with combined collectors, the base of each of these transistors is connected to one of the corresponding resistor, and the emitter-collector junction of each transistor is diode-bounded , with the secondary winding of the transformer through a linear choke connected to the output vyvopvm {2j.

A disadvantage of the known devices is their complexity and low reliability.

The purpose of the invention is to simplify the device, increase its reliability, as well as control the output.

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The goal is achieved by introducing two pairs of field-effect transistors of different conductivity types with combined sources into a known current stabilizer, moreover, the drain of the first field-effect transistor is connected to the second gate and base of the corresponding key transistor, the collector of which is connected to the drain of the second field-effect transistor, the gates of the first field-effect transistors are connected by a pair of hiccups and connected to the bus amp, and the other conclusions of the mentioned resistors are connected to the emitters of the corresponding key transistors. In addition, in order to regulate the output current, the integrated gates of the field effect transistors are connected to the common bus through the input regulated voltage source.

Figures 1 and 2 are a schematic diagram of the proposed device.

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The stabilizer contains a power source 1, a transformer 2, to which the secondary winding is connected in series. Line choke 3 and load 4. 0 Between the collector and the base of transistors 5 and 6 are connected two field-effect transistors 7.8 and 9.10 with channels of additional conduction types, diodes 11 and 12 are connected between collectors and emitters, and the emitter junction is bridged by resistors 13, 14.

The device works as follows.

When the power source 1 is turned on, due to the nonidentity of the characteristics of the field-effect transistors 7.8 and 9.10, the mode is established when transistors 7, 8 are open and transistors 9, 10 are closed or vice versa.

Let the transistors 7, 8 be opened at the considered time instant. In this case, the key transistor 5 operates in an active mode close to the saturation limit. Its collector current, as well as the current through the field conductors 7, 8, increases as the current through the linear choke increases. The circuit of their field-effect transistors 7, 8 has a current-voltage characteristic with a portion of negative permeability. When the current through the field-effect transistors 7, 8 and, consequently, the base current of the transistor 5, is reached, the magnitude of the peak current in the current-voltage characteristic decreases through the field-effect transistors 7, 8 to almost zero. The key transistor 5 is locked in this case, the polarity of the voltages on the windings of the transformer 2 is reversed, the diode 12 is unlocked.

The current flows through the circuit: minus power supply 1, left side of the primary winding of transformer 2, diode 12, plus power supply 1. In this case, part of the energy accumulated in the magnetic field of Drossel 3 is returned to power supply 1. When the throttle 3 is reduced to zero, the diode 12 is locked, the field-effect transistors 9, 10 are unlocked, and, therefore, the CL transistor b. Current throttle 3 begins to increase in the opposite direction. The processes described below are repeated for the other arm of the circuit.

 If the transformer 2 operates in a linear mode and its magnetization current is much less than the current of the throttle 3, then the amplitude of the alternating current in the load 4 does not depend on the voltage of the power supply source 1 and the load magnitude

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current gain

the key of the first tranz of the source; peak current of the circuit and two field-effect transistors with channels of additional conduction types;

  Transformer transformation ratio 2 and the number of turns of the primary and secondary windings.

If necessary, the load can be supplied with stabilized direct current if a rectifier and a smoothing filter are switched on between the linear choke 3 and the load 4.

The device shown schematically in Fig. 1, as well as the known, does not allow the load current to be controlled.

Figure 2 shows a schematic diagram of a stabilizer allowing the load current to be regulated.

This is achieved by connecting an adjustable voltage source 15 between the combined drains of the field effect transistors 8 and 10 connected to the collectors of the key transistors 5 and 6 and the combined gates of the field effect transistors 8 and 10. When the voltage of the source 15 changes, the currents of the current-voltage characteristics of the circuits and field-effect transistors 7, 8 and 9, 10, and thus the amplitude of the load current, change.

The proposed stabilizer is simpler and more reliable than the known one due to the absence of a feedback circuit from the output of the inverter to its input. It makes it easier to regulate the load current.

In addition, the stabilizer is more reliable and simpler in its design when it is supplied with stabilized current for circuits that are under high voltage, since the galvanic isolation of the feedback circuit is not required.

Claims (1)

1. An AC power stabilizer containing an inverter with zero lead of the transformer primary winding on two key transistors with combined collectors, the base of each of these transistors is connected to one of the corresponding resistor outputs, and the emitter-collector junction of each transistor is diode bridged, and the secondary winding of the transformer through a linear choke is connected to the output pins, which is different, so that, in order to simplify the device and increase its reliability, two pairs are inserted into it OLEV transistors of different conductivity type from the combined origins, the drain of the first FET coupled to the gate of the second base and the corresponding transistor, whose collector is connected to the drain of the second field effect transistor, the gate of the first field