CN2062871U

CN2062871U - Ac voltage stabilizer

Info

Publication number: CN2062871U
Application number: CN 89209774
Authority: CN
Inventors: 扬光
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-12-02
Filing date: 1989-12-02
Publication date: 1990-09-26

Abstract

The utility model discloses an AC voltage stabilizer composed of a sampling circuit, a pulse-width adjusting circuit, a power amplification circuit, a failure checking circuit and an AC main circuit. The AC voltage stabilizer adopts an integrated circuit as a primary element of a checking and controlling section, so the AC voltage stabilizer has the advantages of stable performance and long service life. The AC voltage stabilizer can immediately normally work without generating over-voltage output when the power is supplied. The AC voltage stabilizer has an auto-protective function and high reliability, so the AC voltage stabilizer can be used as an AC power supply voltage stabilizer for the computer and the precision instrument.

Description

AC voltage stabilizer

The utility model belongs to the alternating current steady voltage plug technical field.

In alternating current steady voltage plug, widely used mainly is 614 type electronic regulators, it has adopted thermal values such as tungsten filament diode, electron tube big at electronic control part, the easily worn part that life-span is short happens occasionally because these parts damages cause the phenomenon of the instrument and equipment that output voltage rising damage is expensive.This voltage stabilizer needed first preheating before using, could connect with consumer then, if the situation that instantaneous power-down occurs, power on just easily produces overvoltage output, caused the damage of consumer.

The purpose of this utility model provides a kind of output voltage stabilization, does not need the AC voltage regulator of preheating.

Technical essential of the present utility model is:

It is made up of sample circuit, pulse width modulation circuit, power amplification circuit, failure detector circuit and ac main circuit.The transformer Bc of sample circuit will be coupled to the alternating voltage output signal of secondary L1, produce pulsating dc voltage through rectification, send the input end of pulse width modulation circuit after the filtering.The output terminal of pulse width modulation circuit produces the pulse signal of wide variety, adds to the transistor base stage of power amplification circuit.The transistor conduction ratio of power amplification circuit changes with the base stage pulse width variation, and this current signal makes the saturated electric-examination device B of ac main circuit ₂Change the alternating voltage of stable regulation output terminal.The reference power supply output terminal of one group of input of two voltage comparators of failure detector circuit termination pulse width modulation circuit, voltage is surveyed in another group input end reception of two voltage comparators, and the relatively output electric signal of two voltage comparators provides through output terminal.

The utility model has been owing to adopted integrated circuit as detecting and the main element of control section, makes its stable performance, and the life-span is long, energized no matter when, and operate as normal can not produce overvoltage and export immediately.Has the autoprotection function, the reliability height.AC power stable-pressure device as computing machine and exact instrument is more satisfactory.

Fig. 1 is a block scheme of the present utility model.

Fig. 2 is circuit theory diagrams of the present utility model.

Further narrate below in conjunction with accompanying drawing:

Ac main circuit is by autotransformer B ₁, saturable reactor B ₂(or claiming magnetrol), to wait to main element constitutes, a ', b ' two ends are ac voltage input, a, b two ends are the alternating voltage output end of pressure-stabilizing.Nk is magnetrol B ₂The control winding, DC current size among the Nk is flow through in control, can realize alternating voltage output is adjusted.Sample circuit is by transformer Bc, bridge rectifier D ₂Constitute Deng for critical piece, the primary coil of transformer Bc meets ac voltage output a, b, secondary L ₁The alternating voltage that coupling is obtained is through rectifier D ₂Rectification becomes pulsating dc voltage, and then by obtaining the DC voltage of 1.5-3.5 volt, the pulse width modulation circuit that this direct current force feed is made of pulse width modulated assembly M after the Resistor-Capacitor Unit filtering.Inside comprises that the pulse width modulated assembly M input end (2,7) of parts such as error amplifier, reference power supply generator, oscillator gets the DC voltage that sample circuit provides, the DC voltage that changes provides the pulse electrical signal of wide variety through the output terminal (8) of assembly M, is used for the power controlling amplifying circuit.Power amplification output circuit is by bridge rectifier D ₁, transistor BG, voltage stabilizing diode DW be that critical piece constitutes, bridge rectifier D ₁Input end and ac voltage output a, b join, behind ac voltage rectifier, the Nk through being filtered into power output circuit provides power supply, transistor BG(power switch pipe) collector meet rectifier D ₁Output terminal, emitter meets the end of control winding Nk, another termination D of Nk ₁Negative pole, the base stage of BG links to each other with the output terminal (8) of pulsewidth assembly M, voltage stabilizing diode DW is connected across between BG collector and the substrate.When a, b end alternating voltage raises, M output terminal (8) send the pulse narrowing of BG base stage, because the conduction ratio of BG diminishes, then power supply is little by the average electrical mobility that BG offers Nk, the alternating voltage of a, b end is descended, and when the base stage pulse of BG broadened, then conduction ratio increased, average electrical rheology among the Nk is big, and the alternating voltage of a, b end is risen.So just can make ac output voltage keep stable.Transistor BG can adopt modes such as complex pipe, multistage amplification or field effect transistor to constitute as required.Fault secure circuit is that critical piece constitutes by two voltage comparator assembly SB, another winding L of transformer Bc ₂With the detection voltage behind the rectifying and wave-filtering; after dividing potential drop, send two output terminals (3,6) of two voltage comparator SB; compare with the reference voltage of other two input ends (4,5); when output voltage is normal value; the output terminal of two voltage comparators (1,7) is a low level; if when output AC voltage surpassed the upper limit or lower limit, output terminal (1,7) was a high level, this high level signal is delivered newspaper alert and protection.

R1-7 among the figure is a resistance, and C1-5 is an electric capacity, and L is a coil, the model of two voltage comparator SB is LM393, the model of pulse width modulated assembly M is MC34060, and the model of transistor BG is BV406, and ac main circuit of the present utility model adopts former 614 type stabilizator structure forms.

Claims

1, a kind of AC stabilizer has sample circuit, pulse width modulation circuit, power amplification circuit, failure detector circuit and ac main circuit, it is characterized in that the transformer Bc of sample circuit will be coupled to time utmost point L ₁The alternating voltage output signal, produce pulsating dc voltage through rectification, send the input end of pulse width modulation circuit after the filtering; The pulse signal that the pulse width modulated assembly M output terminal of pulse width modulation circuit changes adds to the transistor BG base stage of power amplification circuit; Power amplification circuit transistor BG conduction ratio changes with the base stage pulse width variation; The reference power supply of one group of input of two voltage comparator assembly SB of failure detector circuit termination pulse width adjusting circuit, voltage is surveyed in another group input end reception, and relatively Shu Chu electric signal provides through output terminal.