SU1068912A1 - Multichannel stabilized power supply unit - Google Patents

Abstract

A MULTI-CHANNEL STABILIZED POWER SUPPLY UNIT containing an adjustable source of alternating voltage connected by an output to the primary winding of a power transformer, to which each of the secondary windings of which are connected in series a rectifier and a linear stabilizer, differing in that voltage and feedback signal shaper, while the inputs of the voltage sensor across each separate are connected in parallel to the collector-emittershtl circuits of the control transition tori linear regulators, their vyhdpy vhodg1mi shaper connected to the feedback signal and the output of the latter is connected to the control input of a controlled source of variable-g alternating voltage. (L

Description

The invention relates to electrical engineering, in particular, to secondary power sources, and can be used to power various electrical circuits requiring the supply of a number of stabilized voltages. A multichannel power source is known, which contains a variable voltage source, a rectifier unit, and Of the control transistors, the control device and the current limiting device Q1. The disadvantage of the device is the low efficiency /. caused by the increase in losses. The power at the control transistors of all channels with increasing supply voltage, as well as the increase in losses at the control transistors of the loaded channels during load shedding in other channels of the power source. . The closest in their tech-. The essence of the invention is a multichannel stabilized power supply unit containing a variable voltage source, which is from a master oscillator of a pulse width modulator, a constant voltage converter into a variable voltage, a power transformer, connected to the primary winding to the output of an adjustable source of alternating voltage, and each of the secondary to a rectifier connected in series and a linear stabilizer consisting of a regulating and preventing transistor and control circuits, and a feedback winding to the corresponding input of an arrester-pulse modulator of an adjustable source of alternating voltage, a power amplifier connected, with an input to the master oscillator, and outputs to collectors of pre-regulating transistors G2. A disadvantage of the known device is low efficiency, due to the fact that the magnitude of the feedback winding voltage does not depend on the load of the power source, therefore reducing the load in one of the channels leads to an increase in the voltages at the inputs of other, more loaded channels. This increases the voltage drop across the regulating transistors, which leads to an increase in energy loss in linear stabilizers and, therefore, reduces the efficiency of the entire device. . The purpose of the invention is to increase efficiency. The goal is achieved by the fact that voltage sensors are connected to a multichannel stabilized bathing unit containing a controlled alternating voltage source connected by an output to the primary winding of a power transformer, to each of whose secondary windings connected in series a rectifier and linear stabilizer and a feedback signal conditioner, wherein the inputs of the voltage sensors are separately connected in parallel to the collector-emitter circuits of the control transistors of the line s stabilizers, their outputs are connected to the input of the feedback signal and the output of the latter is connected to a control input regulirue.mogo source AC voltage. The drawing shows a functional diagram of a multi-channel stabilized power supply. The device contains an adjustable source of alternating voltage. Connected by the output to the primary winding 2 of the power transformer 3, to the secondary windings 1M 4-4gch. Of which are connected. Sequentially connected rectifiers 5 -5p with filters and linear stabilizers 6-6p. Linear stabilizers b-6p contain control transistors 7-7p and 8-8p control. Sensors 9-9i voltage their inputs are connected to the collector-emitter junction regulating transitions 7-7, and the outputs to the inputs of the imaging device 10 signal feedback, the output of which is connected to the control to the circuit of the input of the variable source 1 of the alternating voltage. The device works as follows. The voltages of the secondary windings 4-4 of the power transformer 3 are fed to the inputs of the rectifiers 5-5 ", where they are rectified, smoothed and then fed to the collectors of the control transistors 7-7l.,. The control circuits 8-8p compare the potential voltages of the respective 6-6p linear stabilizers with the set and as a function of the error signal set the base currents of the respective control transistors 7-7g, and the increase in the output voltage of the linear stabilizer 6. -bp reduces the base current corresponding to a regulating transistor, and a decrease in voltage to an increase in current. The voltage drop across the control transistor 7-7 increases with decreasing base current. For normal operation of the linear stabilizer, the bbl is necessary so that the voltage drop on the corresponding; the control transistor 7-7p was not lower than a certain permissible value, otherwise the transistor will go into saturation mode and the voltage drop across it will be constant.

A change in voltage at the input of a linear stabilizer 6-6p leads to a change in its output voltage. In this case, the error signal also changes, which leads to such a change in the base current, in which the change in the voltage drop on the corresponding control transistor 7-7p compensates for the change, the voltage at the input of the linear stabilizer b-6p.

The change in voltage at the output of the linear stabilizer 6-6p is determined by the parameters of the circuit 8-8 "l control and is very small. Therefore, My voltage variation at the input of the 6-6p linear stabilizer is almost equal to the voltage change at the corresponding 7-7p control transistor.

Voltage sensors 9–9p measure the actual voltage drop values on the 7–7 control transistors. The feedback signal conditioner 10 selects the minimum signal from the output signals of the sensors 9–9 and the voltage and supplies it to the corresponding input of the adjustable voltage source 1 where the feedback signal is compared with the setpoint and the regulation of the alternating voltage

on the primary winding 2 of the power transformer 3 as a function of the error signal. In this case, the change in the feedback signal leads to such a change in the alternating voltage, at which the change in the feedback signal is compensated.

The resulting change in the feedback signal is determined by the corresponding parameters of the controlled {variable voltage source 1 1 and is insignificant. Therefore, the magnitude of the feedback signal is kept almost constant.

As a feedback signal, the minimum of the output signals of the 9-9vi voltage sensors is selected. This signal corresponds to a voltage drop across the control transistor 7-7g of the most loaded channel, since it decreases due to an increase in the voltage drop across the corresponding rectifier 5-5h.

Thus, the proposed device 5 The device maintains at a predetermined level the voltage drop across the regulating transistor 7–7 p of the most loaded channel, which ensures minimal energy losses in linear stabilizers 6–6 p, thereby increasing the efficiency of the device.

Claims (1)

MULTI-CHANNEL STABILIZED POWER SUPPLY, containing an adjustable AC voltage source, connected by an output to the primary winding of a power transformer, to each of the secondary windings of which a rectifier and a linear stabilizer are connected in series, characterized in that, in order to increase the efficiency, voltage sensors and a shaper are introduced into it feedback signal, while the inputs of the voltage sensors are separately connected in parallel to the collector-emitter circuits of the regulating transistors l linear stabilizers, their outputs are connected to driver inputs the feedback signal and the output of the latter is connected to the control input of the controlled variable voltage source. zismr'Tis