CN210629191U

CN210629191U - Full-bridge backup UPS (uninterrupted power supply)

Info

Publication number: CN210629191U
Application number: CN201922031881.4U
Authority: CN
Inventors: 郭畅; 王业琴; 杨艳; 吴婷婷
Original assignee: Huaiyin Institute of Technology
Current assignee: Huaiyin Institute of Technology
Priority date: 2019-11-22
Filing date: 2019-11-22
Publication date: 2020-05-26
Anticipated expiration: 2029-11-22

Abstract

The utility model relates to the field of uninterrupted power supply, and discloses a full-bridge backup UPS (uninterrupted power supply), which comprises a push-pull booster circuit and a full-bridge inverter circuit, wherein the push-pull booster circuit outputs a 12V input voltage through the push-pull booster circuit and then outputs a direct current 360V voltage; the full-bridge inverter circuit SPWM module adopts unipolar modulation, adopts a bilateral mode on the basis of unipolar modulation, and has certain advantages in inhibiting oscillation of a zero crossing point compared with unilateral control. Compared with the prior art, the utility model discloses the circuit is simple, the reliability is high, and output voltage satisfies the load requirement basically, and push-pull circuit only has a switching element work at a moment, and to the output of the same requirement, switching loss is little, and drive circuit is simple, and easily loading and unloading and debugging, has saved assembly cost for traditional UPS, and wherein transformer has the function of direct current isolation and voltage transformation simultaneously concurrently, and peripheral component figure is less, and the cost is lower.

Description

Full-bridge backup UPS (uninterrupted power supply)

Technical Field

The utility model relates to an uninterrupted power supply field specifically relates to a convert low pressure DC power supply to full-bridge backup UPS power of 220V50 Hz.

Background

UPSs are becoming more and more popular as a backup power source for critical electrical equipment in many critical locations. The method for realizing the single-phase full-bridge backup UPS is analyzed and discussed on the basis of summarizing the existing UPS structures and application occasions at home and abroad. Through characteristic contrast, in daily use, the operating efficiency, the reliability of reserve UPS system all are greater than traditional online UPS system, and the maintenance cost then is less than online system to the noise is low, and the price is cheap relatively, and mainly applicable to the commercial power undulant not big, to the occasion that the power supply quality requirement is not high, reserve UPS all will or get favoured of user in each field.

During normal operation of the backup UPS, the load is powered by mains electricity. When it is detected that a mains interruption causes a sudden voltage change above the rated voltage, the inverter module will provide a regulated output voltage to the critical load within 1 millisecond. The load is switched to the energy storage power supply within 2-4 ms. However, if the load is too large, the backup UPS is overloaded, the current increases, the power supply heats up, and the service life of the power supply is shortened. When the voltage of the mains supply is recovered to be normal, the backup UPS system enables the output voltage of the backup UPS system to be synchronous with the mains supply, and the backup UPS system is in a bypass state after the storage battery is charged.

SUMMERY OF THE UTILITY MODEL

Utility model purpose: to the problem that exists among the prior art, the utility model provides a simple structure, with low costs, full-bridge backup UPS power of reliable operation.

The technical scheme is as follows: the utility model provides a full-bridge backup UPS power supply, which comprises a push-pull booster circuit and a full-bridge inverter circuit;

the push-pull boosting circuit comprises an input capacitor, an input inductor, a pair of switching tubes, a boosting transformer, a rectifier bridge, an output capacitor, an output inductor and a control module; the 12V direct current input voltage is filtered and stored by an input capacitor, the control module controls the two switching tubes to be alternately conducted at the same switching frequency by a fixed frequency, the alternating current is boosted to 360V alternating current by an input inductor and a booster transformer, and the direct current is filtered by a rectifier bridge, an output capacitor and an output inductor to output 360V direct current voltage;

the full-bridge inverter circuit comprises a voltage feedforward control module, a current feedback control module, a unipolar SPWM module, a full-bridge inverter module, a voltage and current sampling module and a filtering module; direct current bus voltage of push-pull boost circuit output does voltage feedforward control, and feedback control is done to the electric current, full-bridge inverter module's A end with filter module's input is connected, its B end with filter module output is connected, and voltage current sampling module is connected with filter module output, and sampling voltage, sampling current input unipolar SPWM module input, unipolar SPWM module output rectifier bridge's trigger pulse inserts full-bridge inverter module g end.

Further, the rectifier bridge is composed of 4 reverse fast diodes.

Further, the control module comprises a single-chip integrated PWM control chip SG 3525.

Furthermore, the full-bridge inverter module is composed of 4 thyristors, every two thyristors are connected in series and then connected in parallel, and each thyristor is reversely connected in parallel by 1 MOS (metal oxide semiconductor) tube and 1 diode.

Furthermore, the filter module comprises an input resistor, an input inductor, a filter inductor and a filter capacitor, wherein one end of the input resistor is connected with the end A of the full-bridge inverter module after being connected with the input inductor in series, the other end of the input resistor is connected with the filter capacitor, and the filter capacitor is connected with the end B of the full-bridge inverter module after being connected with the filter inductor in parallel.

Furthermore, when the unipolar SPWM module of the full-bridge inverter circuit is modulated, one bridge arm performs SPWM modulation output, the other bridge arm performs fundamental wave output, and the filter inductor is connected to the output end of the SPWM modulation bridge arm.

Furthermore, the full-bridge backup UPS power supply further comprises a protection circuit which is a resistance wire, one end of the resistance wire is connected with the power output end, and the other end of the resistance wire is connected with an indicator lamp.

Has the advantages that:

one, the utility model discloses because of most of the time is mains supply, UPS output capacity is strong, does not have strict requirement to load current crest factor, surge coefficient, output power factor, overload etc to the circuit is simple, with low costs, the reliability is high, and output voltage satisfies the load requirement basically.

Secondly, the utility model discloses two power tube operating condition's symmetry when the UPS power is heavy current is guaranteed to the symmetry balanced mode of push-pull partial power supply adoption.

Thirdly, the utility model discloses when low input voltage (being less than 100V, 12V in this patent), push-pull circuit only has a switching element work at a moment, and to the output of the same requirement, switching loss is little, and drive circuit is simple, is particularly useful for the occasion of the transform that steps up.

Four, the utility model discloses at single MOS pipe electric current too big, under the physics cooling can not in time radiating the condition, trade 4 undercurrents, little internal resistance's MOS pipe and the good MOS pipe packaging form of radiating effect, can effectively reduce peak voltage, peak current.

Fifthly, the utility model discloses a full-bridge backup type UPS power easily loads and unloads and the debugging, has saved assembly cost for traditional UPS, has improved production efficiency. The transformer has the functions of direct current isolation and voltage conversion, and has fewer peripheral elements and lower cost.

Drawings

FIG. 1 is a block diagram of a backup UPS of the present invention;

FIG. 2 is a schematic diagram of the push-pull boost circuit of the present invention;

fig. 3 is a MATLAB simulation of a full-bridge inverter of the present invention;

fig. 4 is a unipolar SPWM simulation diagram of the present invention.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings

Referring to fig. 1, 2, 3 and 4:

the utility model relates to a when the commercial power was interrupted, a series of designs were done when the load was switched to energy storage power supply, the utility model discloses used energy storage power supply directly chooses storage battery car power for use (being equivalent to 12V's battery), directly gives the load by its power supply.

A full-bridge backup UPS power supply comprises a push-pull boosting circuit and a full-bridge inverter circuit. The front stage circuit and the rear stage circuit are completely isolated. Chip SG3525 controls preceding stage DC-DC push-pull boosting, and the contravariant part adopts SPWM unipolar control mode, carries out multiple protection to the power, solves the problem that the power heavy current is unilateral to generate heat, the current is unbalanced, to power under-voltage protection, improves the contravariant efficiency of complete machine. The backup UPS is improved, the system inversion output and the commercial power are switched in the same direction under different states of the commercial power, and the uninterrupted power supply of the equipment is realized.

The push-pull booster circuit comprises an input capacitor, an input inductor, a pair of switching tubes, a booster transformer, a rectifier bridge, an output capacitor, an output inductor and a control module; the low-voltage direct-current input voltage is filtered and stored by the input capacitor, the control module controls the two switching tubes to be alternately conducted at the same switching frequency by a fixed frequency, the low-voltage direct-current input voltage is boosted to be 360V alternating current by the input inductor and the booster transformer, and the low-voltage direct-current input voltage is filtered by the rectifier bridge, the output capacitor and the output inductor to output 360V direct-current voltage. In this patent, the rectifier bridge is composed of 4 reverse fast diodes, see fig. 2, and a pair of switching tubes are common switching tubes on the market, and their types are: 190N 08. The control module controls the PWM signal of the switch tube to be generated by a single chip integrated PWM control chip SG3525 control circuit, the voltage and current sampling signal output by the UPS and the overvoltage and overcurrent protection signal in the circuit are sent to the control chip SG3525 to control the output of the PWM signal, and the PWM signal drives the on-off of the switch tube in the push-pull boosting circuit. For driving the boost circuit for converting the dc voltage to another fixed or adjustable dc voltage.

The full-bridge inverter circuit comprises a voltage feedforward control module, a current feedback control module, a full-bridge inverter module (4 high-power MOS (metal oxide semiconductor) tubes IRFP460 and four diodes are connected in an anti-parallel mode respectively), a unipolar SPWM module, an input resistor and an input inductor, a filter inductor and a filter capacitor, and a voltage and current sampling module (a voltage sampling module and a current sampling module).

The circuit samples the direct current bus voltage output by the push-pull boosting module to perform voltage feedforward control, and samples the output current to perform feedback control. The full-bridge inversion module is composed of 4 thyristors, the 4 thyristors are divided into two groups, the two groups of thyristors are connected in series and then connected in parallel with the other group, the thyristors are formed by reversely connecting high-power MOS (metal oxide semiconductor) tubes and diodes in parallel, and the type of the MOS tubes is IRFP 460. The input resistor is connected with the input inductor in series, one end of the input resistor is connected with the A end of the full-bridge inverter module, and the other end of the input resistor is connected with the filter capacitor; the filter capacitor is connected with the filter inductor in parallel; the sampling voltage is input to the In1 end of the unipolar SPWM module, the sampling current is input to the In2 end of the unipolar SPWM module, and the output end of the unipolar SPWM module is connected to the g end of the full-bridge inverter module. According to the unipolar SPWM module of the full-bridge inverter circuit, one bridge arm performs SPWM modulation output during SPWM unipolar modulation, the other bridge arm performs fundamental wave output, a filter inductor is connected at the output end of the unipolar SPWM modulation bridge arm, a voltage sampling module is also connected at the output end of the SPWM modulation bridge arm inductor, error calculation is performed on the measured feedback peak voltage and the internal reference sine wave peak voltage, and corresponding adjustment is performed on the output voltage value. The SPWM module of the circuit adopts unipolar modulation, and has the advantages of low loss, small electromagnetic interference, no switching frequency level harmonic wave and the like compared with bipolar control; and a bilateral mode is adopted on the basis of unipolar modulation, so that the method has certain advantages in inhibiting oscillation of a zero crossing point compared with unilateral control.

Two paths of reverse square waves generated by PWM waves output by the power supply drive the on-off of a switch tube in the push-pull booster circuit, so that the purpose of controlling the output voltage is achieved.

After sampling and signal conditioning, the output voltage is sent to pin 1 of SG3525, pin 1 is the reverse input end of the error amplifier, and the feedback signal is connected to the pin to form closed-loop control. PWM waves generated by a control chip SG3525 pass through an isolation driving circuit and then drive a switching tube in a push-pull boosting circuit, direct-current input voltage is boosted to a set value to be output, the driving circuit is a common driving circuit, and the driving circuit also integrates the functions of voltage, current and temperature protection, an LED alarm display function and a fan control function, can output the signals through 50/60Hz set by a jumper, and has a soft start function and a dead zone size. The driving link also plays a role in isolating the main power circuit from the control circuit.

The full-bridge backup UPS power supply also comprises a protection circuit (namely an overvoltage and overcurrent protection circuit), wherein a high-fusing resistance FUSE is arranged in the protection circuit, one end of the protection circuit is connected with the power supply output end, and the other end of the protection circuit is connected with an indicator light, so that the current is limited below a conductive bottleneck at any point in the circuit to avoid overload or short circuit. When the lamp is on, the electric power is output to the control circuit, otherwise, when the lamp is off, the current is too large or short-circuited, the fuse is fused, and the circuit is cut off (at the moment, the fuse is timely maintained and replaced).

The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose of the embodiments is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention, which cannot limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered by the protection scope of the present invention.

Claims

1. A full-bridge backup UPS power supply is characterized by comprising a push-pull booster circuit and a full-bridge inverter circuit;

2. A full-bridge backup UPS power supply as claimed in claim 1 wherein said rectifier bridge is comprised of 4 reverse fast diodes.

3. The full-bridge backup UPS power supply of claim 1 wherein the control module comprises a monolithic integrated PWM control chip SG 3525.

4. A full-bridge backup UPS power supply according to claim 1 wherein the full-bridge inverter module is composed of 4 thyristors, each thyristor is connected in series and then connected in parallel, each thyristor is connected in anti-parallel with 1 diode and 1 MOS transistor.

5. The full-bridge backup UPS according to claim 1, wherein the filter module comprises an input resistor, an input inductor, a filter inductor and a filter capacitor, wherein one end of the input resistor and the input inductor is connected with the A end of the full-bridge inverter module after being connected in series, the other end of the input resistor and the input inductor is connected with the filter capacitor, and the filter capacitor and the filter inductor are connected with the B end of the full-bridge inverter module after being connected in parallel.

6. The full-bridge backup UPS according to claim 5, wherein when the unipolar SPWM module of the full-bridge inverter circuit modulates, one bridge arm is used for SPWM modulation output, the other bridge arm is used for fundamental wave output, and the filter inductor is connected with the output end of the SPWM modulation bridge arm.

7. A full-bridge backup UPS power supply according to claim 1 further comprising a protection circuit which is a resistance wire with one end connected to the power output and the other end connected to an indicator light.