RU1823102C - Stabilized power supply source - Google Patents

Abstract

Usage: power supply of electronic electronic semiconductor equipment. SUMMARY OF THE INVENTION: for single short-term deviations of the output voltage from the nominal value, which are achieved by introducing into the stabilized power supply of the key (23) a self-locking time relay (24), the first and second rectangular pulse generators (25, 26). 1 ill.

Description

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The invention relates to electrical engineering, in particular, for use in systems of stabilized secondary power supply of electronic equipment, as well as computer and automation equipment.

The aim of the invention is to increase the reliability of protection and improve performance.

The drawing shows an electrical functional diagram of a stabilized power supply.

The stabilized power supply includes a transistor inverter 1 having positive and negative inputs 2, 3, and first, second load outputs 4, 5, a shaper-distributor of control pulses 6, a driving generator 7, a transformer 8, a current sensor 9, and an output rectifier 10 , an output filter 11, a signal transducer of a current sensor 12, a ballast resistor 13, a sawtooth voltage generator 14, a voltage limiter 15, a pulse-width modulator 16, a feedback amplifier 17, a reference voltage source 18, minimum protection unit the maximum and maximum output voltage 19, the positive and negative output terminals of the power supply 20, 21, the last of which is common, the auxiliary voltage block 22, the key 23, a time relay with self-locking 24, the first and second rectangular pulse generator 25 , 26, to the first and second load outputs 4, 5 of the transistor inverter 1 are connected in series the primary winding of the transformer 8 and the measuring element of the current sensor 9, the first, second and third terminals of the secondary winding of the transformer 8 are connected respectively with the first, second and third inputs of the output rectifier 10, the first output of which is connected to the first input of the output filter 11. and the second output is connected to the second input, the first and second outputs of the output filter 11 are connected respectively to the plus and minus output terminals of the source power supply 20, 21, the positive output terminal 20 is connected to the input of the protection unit for the minimum and maximum output voltage 19 and the first input of the feedback amplifier 17, the second input of which is connected to the first output of the reference voltage source 18, the second th output of the reference voltage source 18 is connected to the common bus, GTF

the equalizing inputs of the transistor inverter 1 are connected to the corresponding control outputs of the driver-distributor of control pulses

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6, the first input of which is connected to the output of the pulse-width modulator 16, and the second input is connected to the output of the master oscillator 7, the output of the master generator 7 is simultaneously connected to the input of the sawtooth voltage generator 14, the output of which is connected to the first input of the pulse-width modulator 16, the second input of the pulse-width modulator 16 is connected to the output of the feedback amplifier 17, the output of which is simultaneously connected to the output of the voltage limiter 15 and the first output of the switch 23, the second output of which is connected to the common bus the first, second and second outputs of the current sensor 9 are connected respectively to the first and second inputs of the rectifier of the signals of the current sensor 12, the first output of which is connected to the first output of the ballast resistor 13, and the second output is connected to the second output and the common bus, the first input of the voltage limiter 15 is connected to the movable contact of the ballast resistor 13, and the second input is connected to the second terminal of the ballast resistor 13, the inputs of the first and second rectangular pulse generators 25, 26 are connected respectively to the first and second outputs of the block protection of the minimum and maximum output voltage 19, the first outputs are connected to the control input of the key 23, the input of which is simultaneously connected to the output of the self-locking time relay 24, the second outputs of the first and second rectangular pulse generators 25, 26 are connected to self-locking time relay output 24.

A stabilized power supply operates as follows.

When the supply voltage Un is connected to the device, the transistors of the inverter 1 are locked and come into operation when the service voltage Unl is applied to the auxiliary voltage unit 22, since this provides power to all functional units of the power supply. The master oscillator 7 starts to work, generating rectangular pulses, which, through the second input of the driver - distributor of control pulses 6, are fed to the input of the trigger-phase splitter 29 and to the first inputs of the first and second logic elements And 30, 31. The pause between pulses determines the minimum pause time between the on states of the inverter transistors 1. preventing the occurrence of through currents in them. The sawtooth voltage generated at node 14 is compared in pulse-width modulator 16 to the output signal of feedback amplifier 17.

which depends on the difference between the voltages supplied to the first input of the feedback amplifier 17 from the output terminals of the power source 20, 21 and to the second input from the output of the reference voltage source 18, From the output of the pulse-width modulator 16 angular pulses, the duration of which is determined by the value of the signal at the output of the feedback amplifier 17, are fed through the first input of the driver-distributor of control pulses 6 to the second inputs of the first and second logic elements And 30, 31. To the third inputs of the first and second For the logical elements And 30, 31, rectangular pulses are supplied respectively from the first and second outputs of the trigger-phase splitter 29. The low level of the output voltage of the feedback amplifier 17 corresponds to the short duration of the pulses generated by the pulse-width modulator 16 and, accordingly, to the high level of the output voltage wives - great duration. Logically processed by elements And 30. 31 signals in the form of rectangular pulses are fed to the first and second inputs of the amplifier-pulse distributor 32, which generates the number of amplified bipolar control pulses necessary depending on the implementation of the transistor inverter 1 and distributes them between the corresponding control the transistor inverter 1 inputs. As a result of unlocking and locking the transistors of the inverter 1 in turn in the windings of the transformer 8 and the current-measuring element of the current sensor 9, it forms with a variable voltage of a rectangular shape with pauses between positive and negative impulses. Next, the alternating voltage of the secondary winding of the transformer 8 is rectified by the output rectifier 10 and filtered by the output filter 11, as a result of which at the output terminals of the power supply 20, 21 the output voltage of the mains is constant taking into account the compensation of the destabilizing effects (changes in the supply voltage 1) and load current). The alternating pulse voltage of the secondary winding of the current-measuring element of the current sensor 9 is rectified by the signal rectifier of the current sensor 12 and, through the ballast resistor 13 used as the voltage regulator, is supplied to the inputs of the voltage limiter 15, which is an adjustable shunt connected to feedback amplifier output 17. With increasing load current of the power supply over

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a certain value, the voltage at the input of the current sensor 9 increases, which causes a proportional decrease in the shunt resistance, which is a voltage limiter 15, respectively, a decrease in the output voltage of the feedback amplifier 17 and a decrease in the duration of the control pulses. As a result, the open time of the transistors of the inverter 1 is limited, which leads to a decrease in the output voltage of the UBUX power supply. The limiting effect of the voltage limiter 15 is the greater, the greater the signal supplied to its inputs from the ballast resistor 13. At a certain minimum voltage value at the output terminals of the power source 20. 21, to which the input of the protection unit is connected to the minimum and maximum output voltage 19, the undervoltage comparator 27 of the protection unit 19 is activated and the output t to the input of the first rectangular pulse generator 25 triggering signal, causing the appearance of the first and second outputs of this rectangular pulse generator. From the first output, the pulses are fed to the control input of the key 23, opening and closing the key 23 with a pulse repetition rate. Each time you open 23. the feedback amplifier 17 shunting the output, EN.COD-. but the voltage of the amplifier 17 receives a value at which the pulse-width modulator 16 stops generating pulses and the transistor inverter 1 is turned off. In a pause after each pulse received at the control input of the key 23, the transistor inverter 1 is turned on. If, in this case, the overload causing the undervoltage comparator 27 of the protection unit 19 to disappear has disappeared, the stabilized lithium source enters into a stable mode of operation with the rated output voltage. If the emergency overload persists, then due to the pulses from the second output of the first generator of rectangular pulses 25 to the input of the time relay with self-locking 24. after a certain time, a stable signal will arrive at the control input of the key 23, opening the key 23 and causing the transistor to be completely closed inverter 1. The number of repeated shutdowns and turns on the power supply when an emergency overload occurs is determined by the parameters of the pulses generated by the first square-wave generator 25 parametrlmi

self-locking time relay 24 Since the operation of protection to minimize the output voltage accompanies each switching on of the stabilized power supply until the rising output voltage reaches the value corresponding to the protection cut-off threshold, the possibility of emergency current overload of the transistor inverter 1 when switching on the source is excluded power to a faulty load.

When the output voltage of the power source is increased to the level of operation of the comparator of the voltage increase 28, a trigger signal is issued to the input of the second rectangular pulse generator 26 from the second output of the block 19. From the first output of the generator 26, the pulses are fed to the control input of the key 23, and from the second output to the input of the time relay with self-locking 24. In this case, the key 23 and the time relay with self-locking 24 work in the same way as in case of emergency overload, but with a different pulse duration and a different pulse repetition rate. The duration of the pulses and their duty cycle both for protection against overload and for protection against overvoltage is selected depending on the operating hours of the transistor inverter 1, which has a margin for adjusting the output voltage and output parameters in the power supply file 11.

The use of the invention will make it possible, in comparison with the prototype, to increase the reliability of protection operations and improve the operational characteristics of a stabilized power supply by preventing the output voltage of the power supply lines from exceeding the permissible level for any disturbing influences in the direction of the power supply network, in the load or when a malfunction occurs in the power supply system itself; the impossibility of increasing the load current above a predetermined limit value; uninterrupted power supply of the load during short-term single changes in the output voltage of the electric power supply lines reaching emergency levels (absence of false positives); to remove the output voltage of the IVEP by the built-in means while maintaining stable signs of an emergency state.

Claims (1)

The claims Stable power supply. comprising a transistor inverter having positive and negative inputs, first and second load outputs, a driver-distributor of control pulses, a master oscillator, a transformer, a current sensor, an output rectifier, an output filter, a rectifier of current sensor signals, a ballast resistor, a sawtooth generator, a limiter voltage, pulse-width modulator, feedback amplifier, reference voltage source, protection block for minimum and maximum output voltage, plus and minus output power supply odes, the last of which is the auxiliary voltage unit, the transformer primary inverter and the current transformer measuring element are connected in series to the first and second load outputs of the transistor inverter, the first, second, third terminals of the transformer secondary winding are connected respectively to the first, second , the third inputs of the output rectifier, the first output of which is connected to the first input of the output filter, and the second output is with the second input, the first and second outputs are output of the filter are connected respectively to the positive and negative output terminals of the power source, the control inputs of the fan inverter of the inverter are connected to the corresponding control outputs of the driver-distributor of control pulses, the first input of which is connected to the output of the pulse-voltage modulator, and the second input is output from the master the generator, the output of the master generator is simultaneously connected to the input of the sawtooth voltage generator, the voltage of which is connected to the first input of the pulse-width modulator, the second the input of the pulse-width modulator is connected to the output of the feedback amplifier, the output of which is simultaneously connected to the output of the voltage limiter, the first input of the feedback amplifier is connected to the input of the protection unit to minimize and maximum the output voltage and to the positive output terminal of the power supply, the second input is connected to the first output of the reference voltage source, whose output is connected to a common bus, the first and second outputs of the current sensor are connected to the corresponding rectifier inputs of the current sensor signals a, the first output of which is connected to the first terminal of the ballast resistor, and the second output is connected to the second terminal of the ballast resistor and a common bus, characterized in that, in order to increase the reliability of the protection and improve the operational characteristics, a key, a time relay with self-locking, the second outputs of the first and second generators, the first and second generators of rectangular angular pulses are connected to pulses, the inputs of which are connected by the input of a time relay with self-locking, respectively, with the first and second outputs — the first output of the key is connected to the output the protection block minimum and maximum 5 feedback amplifier, and the second output is the output voltage, the first outputs with a common bus, the first input of the limiter are connected to the control input of the switch, the voltage connected to the movable contact, the input of which is simultaneously connected to the output of the ballast resistor, and the second input by way of the self-locking time relay, with the second output of the ballast resistor.