CN201422077Y - Power supply device - Google Patents

Abstract

The utility model discloses a power supply, power supply includes bridge rectifier, main power converter, standby power converter, rechargeable battery, two-way electric energy converter and two-way conversion controller. The utility model also discloses a power supply, power supply includes: a bridge rectifier, a main power converter, a standby power converter, a rechargeable battery and a boost converter. The utility model discloses an increase rechargeable battery in power supply for can improve the standby power supply stability of standby power converter output when normal mode, and can close standby power converter when standby mode and change and provide standby power by rechargeable battery, thereby power loss when reducing standby mode.

Description

a power supply

technical field

The utility model relates to the field of electronic technology, in particular to a power supply.

Background technique

FIG. 1 is a block diagram of a power supply for liquid crystal displays provided in the prior art. Referring to Fig. 1 , the working modes of the power supply 1 include two kinds of normal mode (on mode) and standby mode (stand-by mode), and the power supply 1 includes an electromagnetic interference filter 11, a bridge rectifier 12, and a main power converter 13 , standby power converter 14, power switch 15 and optional power factor corrector 16. The power supply 1 receives an AC power Vac, and the typical voltage of the AC power Vac is 90-264Vrms. After receiving the AC power supply Vac, the electromagnetic interference filter 11 first filters out the electromagnetic interference in the AC power supply Vac, and the bridge rectifier 12 then converts the voltage of the AC power supply Vac that filters out the electromagnetic interference into a DC voltage Vbus and sends it to the main power supply for conversion. converter 13 and standby power converter 14. However, because the bridge rectifier 12 will cause the current distortion of the AC power supply Vac, generally an active factor corrector 16 is provided at the rear end of the bridge rectifier 12, so that the power supply 1 viewed from the input terminal of the AC power supply Vac can be virtualized as an approximate No reactive power loss systems with resistive loads, especially electronic devices with a power above 75W, currently need to add a power factor corrector to meet the requirements of harmonic current regulations.

When the main power converter 13 is in the normal mode, it performs power conversion to convert the DC voltage Vbus into the main power sources Vm1 and Vm2 for output; and in the standby mode, it stops the power conversion and no longer outputs the main power sources Vm1 and Vm2. The standby power converter 14 performs power conversion no matter in the normal mode or the standby mode to convert the DC voltage Vbus into the output standby power Vsb and provide the internal DC power Vcc. Among them, the typical voltage value of the main power supply Vm1 is 24V, which is converted into a high-voltage AC voltage by an inverter to light up the backlight source of the LCD; the typical voltage value of the main power supply Vm2 is 12V, which supplies power to the audio amplifier and the LCD display. Audio-visual processing circuit; the typical value of the standby power supply Vsb voltage is 5V, which supplies power to the microcontroller on the LCD main board; the typical value of the voltage of the internal DC power supply Vcc is 16V, which supplies power to the power supply 12 inside such as the main power conversion Controller 13 and power factor corrector 16, etc.

The microcontroller is used to monitor whether the user presses the power button on the remote control (or the display control panel), thereby outputting a power switch signal PS to control the power supply 1 to switch between the normal mode and the standby mode. For example, when the power switch signal PS is at a high level (or logic 1), the power supply 1 is controlled to work in the normal mode. At this time, the power switch 15 is turned on, and the DC power supply Vcc supplies power to the main power converter 13 and power factor correction. The controller of the device 16 controls the main power converter 13 and the power factor corrector 16 to perform power conversion and output the main power Vm1 and Vm2 to the inverter, audio amplifier and audio-visual processing circuit of the liquid crystal display, so that the liquid crystal display is turned on and can display a picture . At this time, once the microcontroller detects that the user presses the power button, the output power switch signal PS will change from high level (or logic 1) to low level (or logic 0). When the power switch signal PS is low level (or logic 0), the control power supply 1 works in the standby mode. At this time, the power switch 15 is turned off, and the DC power supply Vcc no longer supplies power to the main power converter 13 and power factor correction. The controller of the device 16 makes the main power converter 13 and the power factor corrector 16 stop the power conversion and no longer output the main power Vm1 and Vm2 to the liquid crystal display, so that the liquid crystal display is turned off, and at this time, once the microcontroller monitors the user When the power button is pressed, the output power switch signal PS will change from low level (or logic 0) to high level (or logic 1).

When the power supply is in standby mode, it must meet the requirements of relevant energy-saving regulations, so the conversion efficiency of the standby power converter is particularly important. The standby power converter 14 of the power supply 1 in the prior art usually adopts a flyback structure, and its conversion efficiency is less than 50% when it works at a light load, and there is limited room for improvement in conversion efficiency or power loss. It is difficult to adapt to the requirements of increasingly stringent energy-saving regulations. In addition, the load at the back end of the standby power converter 14 is a precision integrated circuit chip such as a microcontroller, so the output of the standby power Vsb has to consider the error range value in terms of power supply stability. Generally, the error is required to be within 5-10%. However, as chips continue to evolve and update, there may be a requirement that the error be within 1% in the future, and the power supply 1 of the prior art will not be able to meet such a requirement.

Utility model content

In order to reduce the power loss of the power supply in standby mode, it can meet the requirements of increasingly stringent energy-saving regulations; and improve the power supply stability of the standby power supply, and can supply power to loads that have strict requirements on power supply stability, such as increasingly sophisticated micro-controllers Integrated circuit chips such as devices. The utility model provides a power supply, and the technical solution is as follows:

On the one hand, the utility model provides a power supply, the working mode of the power supply includes a normal mode and a standby mode, and in the normal mode and the standby mode, the output terminal of the power supply Both output standby power, the power supply includes:

Bridge rectifiers, main power converters, standby power converters, rechargeable batteries, bi-directional power converters and bi-directional conversion controllers;

The bridge rectifier is used to convert the voltage input by the AC power supply into a DC voltage;

The main power converter, connected to the bridge rectifier, is used to convert the DC voltage into at least one main power voltage output in the normal mode, and stop the conversion in the standby mode;

The standby power converter is respectively connected to the output terminal of the power supply and the bridge rectifier, and is used to convert the DC voltage into an output voltage and output it to the power supply in the normal mode. The output terminal of is used as the standby power supply voltage, and stops converting when in the standby mode;

The rechargeable battery is respectively connected to the bidirectional power converter and the bidirectional conversion controller;

The bidirectional power converter has a high voltage terminal, a low voltage terminal and a control terminal, the high voltage terminal of the bidirectional power converter is connected to the output terminal of the power supply, and the low voltage terminal of the bidirectional power converter is connected to the A rechargeable battery, the control terminal of the bidirectional power converter is connected to the bidirectional conversion controller;

The bidirectional conversion controller is respectively connected to the output terminal of the power supply, the rechargeable battery and the control terminal of the bidirectional power converter, and is used to operate in the normal mode and the standby power supply voltage is greater than a predetermined When setting a value, control the bidirectional power converter to convert the standby power supply voltage to charge the rechargeable battery; in the normal mode and when the standby power supply voltage is less than the preset value, control the The bidirectional power converter converts the terminal voltage of the rechargeable battery and transmits it to the output terminal of the power supply to stabilize the standby power supply voltage; and in the standby mode, controls the bidirectional power converter to After the terminal voltage of the rechargeable battery is converted, it is sent to the output terminal of the power supply as the standby power supply voltage.

On the other hand, the utility model also provides a power supply, the working mode of the power supply includes a normal mode and a standby mode, and in the normal mode and the standby mode, the power supply The output terminals all output standby power, and the power supply includes:

Bridge rectifiers, main power converters, standby power converters, rechargeable batteries and boost converters;

The bridge rectifier is used to convert the voltage input by the AC power supply into a DC voltage;

The main power converter, connected to the bridge rectifier, is used to convert the DC voltage into at least one main power voltage output in the normal mode, and stop the conversion in the standby mode;

The standby power converter is connected to the bridge rectifier and the rechargeable battery respectively, and is used to convert the DC The voltage is converted into an output voltage and output to the output terminal of the power supply as the standby power supply voltage, and output to the rechargeable battery to charge it; and in the standby mode and the voltage of the rechargeable battery is sufficient, stop conversion;

The rechargeable battery is connected to the standby power converter and the boost converter respectively;

The boost converter has a high voltage terminal and a low voltage terminal, the high voltage terminal is connected to the output terminal of the power supply, and the low voltage terminal is connected to the rechargeable battery.

The beneficial effects of the technical solution provided by the utility model are:

By adding a rechargeable battery to the power supply, the stability of the standby power supply output by the output of the standby power converter can be improved in the normal mode, and the standby power converter can be turned off in the standby mode to be provided by the rechargeable battery. power supply, thereby reducing power loss in standby mode.

Description of drawings

Fig. 1 is a block diagram of a power supply applied to a liquid crystal display provided by the prior art;

Fig. 2 is a block diagram of a power supply provided by Embodiment 1 of the present utility model;

Fig. 3 is a circuit diagram of a power supply shown in Fig. 2 provided by Embodiment 1 of the present utility model;

Fig. 4 is a timing diagram of signals in the complementary switch control signal generator shown in Fig. 3 provided by Embodiment 1 of the present invention;

Fig. 5 is a block diagram of a power supply provided by Embodiment 2 of the present invention;

FIG. 6 is a circuit diagram of a power supply shown in FIG. 5 provided by Embodiment 2 of the present invention.

In the accompanying drawings, the components represented by each label are as follows:

1, 2, 5: Power supply; 11, 21: Electromagnetic interference filter;

12, 22: bridge rectifier; 13, 23: main power converter;

14, 24, 54: standby power converter; 15, 25: power switch;

16, 26: power factor corrector; 20, 50: output terminal of power supply;

27: Bidirectional power converter; 271: High voltage end of bidirectional power converter;

272: the low-voltage terminal of the bidirectional power converter; 273: the control terminal of the bidirectional power converter;

28: Rechargeable battery; 29: Two-way conversion controller;

291: standby power detector; 292: battery detector;

57: Boost converter; 571: Low voltage side of boost converter;

572: High voltage side of boost converter; ADD1: Adder;

AND1: AND gate; B1, B2: rechargeable battery

C1～C3: Capacitor; CMP1: Comparator;

CMP2: Pulse Width Modulation Comparator D1～D3: Diodes;

L1, L2: capacitor; Na: auxiliary winding;

Np: primary winding; Ns: secondary winding;

NOT1: NOT gate; OPA1, OPA2: Operational amplifier;

OSC1: monostable multivibrator; Q1～Q3: power switch;

Q4, Q5: switch; R1～R16: resistor;

SUB1: Subtractor; T1: Transformer;

XOR1, XOR2: XOR gate; ZD1, ZD2: Zener diode;

Vac: AC power supply; Vbus: DC voltage;

Vcc: internal DC power supply; Vm1, Vm2: main power supply;

Vsb: standby power supply; Vsb’: standby power detection voltage;

Vbat: battery terminal voltage; Vbat’: battery detection voltage;

PS: Power switch signal; V1～V4: DC voltage;

Vref: reference voltage; Vset: preset voltage;

Vst: slope voltage; Vpwm: pulse width modulation signal;

Vp1, Vp2: dead zone pulse; Vdr1, Vdr2: switch control signal;

Vfb: feedback signal; T: period;

Ton: enable period; Toff: disable period;

d1, d2: dead time; ζ1, ζ2: duty cycle.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present utility model clearer, the implementation of the present utility model will be further described in detail below in conjunction with the accompanying drawings.

Example 1

The embodiment of the present utility model provides a power supply, see FIG. 2 which is a block diagram of the power supply provided by the first embodiment of the present utility model.

Referring to FIG. 2 , the working modes of the power supply 2 include normal mode and standby mode, and in both the normal mode and the standby mode, the output terminal 20 of the power supply 2 outputs the standby power Vsb. The power supply 2 includes an EMI filter 21, a bridge rectifier 22, a main power converter 23, a standby power converter 24, a power switch 25, an optional power factor corrector 26, a bi-directional power converter 27, a rechargeable battery 28. Bidirectional conversion controller 29, standby power detector 291 and battery detector 292.

Among them, the circuit connections and functions of the electromagnetic interference filter 21 , bridge rectifier 22 , main power converter 23 , power switch 25 and power factor corrector 26 are similar to those of the prior art, and will not be repeated here. It should be noted that the standby power converter 24 is different from the prior art. In the normal mode, it performs power conversion to convert the DC voltage Vbus into an output voltage and outputs it to the output terminal 20 as the voltage of the standby power supply Vsb, and in the standby mode When the power conversion is stopped, the output voltage will no longer be output.

The standby power detector 291 is connected to the output terminal 20 of the power supply 2 for detecting the voltage of the standby power Vsb and outputting a corresponding standby power detection voltage Vsb'. The battery detector 292 is connected to the rechargeable battery 28 for detecting the terminal voltage Vbat of the rechargeable battery 28 and outputting a corresponding battery detection voltage Vbat'. The bidirectional power converter 27 has a high voltage terminal 271, a low voltage terminal 272 and a control terminal 273, the high voltage terminal 271 is connected to the output terminal 20 of the power supply 2, the low voltage terminal 272 is connected to the rechargeable battery 28, and the control terminal 273 is connected to the bidirectional conversion control Device 29. The bidirectional conversion controller 29 is connected to the standby power detector 291, the battery detector 292 and the bidirectional power converter 27, and is used to control the bidirectional power according to the received power switch signal PS, the standby power detection voltage Vsb' and the battery detection voltage Vbat' The converter 27 performs electric energy conversion.

When the power switch signal PS, for example, is high level (or logic 1) to control the power supply 2 to work in the normal mode, the power supply 2 will output the main power Vm1, the main power Vm2 and the standby power Vsb to provide to each LCD circuit device. When the voltage of the standby power supply Vsb is greater than the preset value, the bidirectional conversion controller 29 controls the bidirectional power converter 27 as a step-down (buck) converter, and the bidirectional power converter 27 converts the voltage of the standby power supply Vsb at the high voltage terminal 271 into a low-voltage DC voltage Finally, output from the low-voltage terminal 272 to the rechargeable battery 28 to charge the rechargeable battery 28, and the bidirectional conversion controller 29 also controls the bidirectional power converter 27 to adjust the low-voltage DC voltage output from the low-voltage terminal 272 according to the battery detection voltage Vbat'. When the voltage of the standby power supply Vsb is lower than the preset value, for example, when the voltage of the standby power supply Vsb drops to the preset value instantaneously due to a change in the load of the back-end micro-controller, the bidirectional conversion controller 29 controls the bidirectional power converter 27 as a step-up voltage. (boost) converter, the bidirectional power converter 27 converts the terminal voltage Vbat of the rechargeable battery 28 at the low voltage terminal 272 into a high voltage DC voltage, and outputs it from the high voltage terminal 271 to the output terminal 20 to stabilize the voltage of the standby power supply Vsb. The bidirectional conversion controller 29 also controls the bidirectional power converter 27 to adjust the high voltage DC voltage output from the high voltage terminal 271 according to the magnitude of the standby power detection voltage Vsb'. Wherein, the preset value can be set to be any voltage value that is lower than the rated voltage (such as the above-mentioned typical value of 5V) but still enables the back-end load to work normally.

When the power switch signal PS is, for example, low level (or logic 0) to control the power supply 2 to work in the standby mode, the standby power converter 24 stops power conversion and no longer outputs the output voltage as the standby power Vsb voltage. Instead, the bidirectional power converter 27 is controlled by the bidirectional conversion controller 29 as a boost converter. After the bidirectional power converter 27 converts the terminal voltage Vbat of the rechargeable battery 28 at the low voltage terminal 272 into a high voltage direct current voltage, it is output from the high voltage terminal 271 to The output terminal 20 is used as the standby power supply Vsb voltage. The bidirectional conversion controller 29 also controls the bidirectional power converter 27 to adjust the high voltage DC voltage output from the high voltage terminal 271 according to the magnitude of the standby power detection voltage Vsb'.

Therefore, the power supply 2 of the present invention connects the rechargeable battery 28 in parallel to the output end of the standby power converter 24 through the bidirectional power converter 27 . When the power supply 2 works in the normal mode, the standby power Vsb output from the output terminal of the standby power converter 24 can charge the rechargeable battery 28 through the bidirectional power converter 27 . And when the standby power Vsb output by the standby power converter 24 is unstable due to load changes, the rechargeable battery 28 can stabilize the standby power Vsb output by the standby power converter 24 through the bidirectional power converter 27 . In addition, when the power supply 2 works in the standby mode, the standby power converter 24 can be turned off and the rechargeable battery 28 can provide the standby power Vsb through the bidirectional power converter 27, so that the input power loss can be much lower in the standby mode. In line with the requirements of existing energy-saving regulations.

FIG. 3 is a circuit diagram of the power supply shown in FIG. 2, and only the standby power converter 24, the bidirectional power converter 27, the rechargeable battery 28, the bidirectional conversion controller 29, and the standby power supply in the power supply 2 are described here. The specific circuit diagram of the detector 291 and the battery detector 292.

Referring to FIG. 3 , the standby power converter 24 adopts a flyback architecture, and performs power conversion by controlling the switching of the power switch Q3 in the normal mode. When the power switch Q3 is turned on, the primary winding Np of the transformer T1 is connected to the DC voltage Vbus, so that the magnetic flux of the transformer T1 increases. At this time, the output of the secondary winding Ns of the transformer T1 will cause the diode D1 to be reverse-biased and disconnected, so that the capacitor C1 The stored energy is provided to an output 20 load. When the power switch Q3 is turned off, the energy stored by the transformer T1 is supplied to the capacitor C1 and the output terminal 20 load. An inductor L2 and a capacitor C2 are usually provided between the capacitor C1 and the output terminal 20 to filter out high-frequency signals generated when the power switch Q3 switches. In addition, the auxiliary winding Na of the transformer T1 supplies an internal DC power supply Vcc through rectification by the diode D2 and filtering by the capacitor C3.

The bidirectional power converter 27 includes a first power switch Q1, a second power switch Q2 and an inductor L1. Both the first power switch Q1 and the second power switch Q2 have a first terminal, a second terminal and a control terminal, and the inductor L1 has a first terminal and a second terminal. The first end of the first power switch Q1 is connected to the high voltage end 271 of the bidirectional power converter 27, the first end of the second power switch Q2 is connected to the second end of the first power switch Q1, and the second end of the second power switch Q2 terminal connected to the ground potential, the first terminal of the inductor L1 is connected to the second terminal of the first power switch Q1 and the first terminal of the second power switch Q2, and the second terminal of the inductor L1 is connected to the bidirectional power converter 27 The low-voltage terminal 272, the control terminal of the first power switch Q1 and the control terminal of the second power switch Q2 are respectively connected to the bidirectional conversion controller 29 through the control terminal 273 of the bidirectional power converter 27 to receive the switch control output by the bidirectional conversion controller 29 Signals Vdr1 and Vdr2. When the bidirectional power converter 27 is used as a step-down converter, its power flow flows from the high-voltage terminal 271 to the low-voltage terminal 272, and the duty ratio ζ1 of the first power switch Q1 is adjusted according to the battery detection voltage Vba t' to adjust the low-voltage terminal. The magnitude of the low-voltage DC voltage output by 272, at this time, the duty cycle of the second power switch Q2 is (1-ζ1). When the bidirectional power converter 27 is used as a boost converter, its power flow flows from the low-voltage terminal 272 to the high-voltage terminal 271, and the duty ratio ζ2 of the second power switch Q2 is adjusted according to the magnitude of the standby power detection voltage Vsb' to adjust the high-voltage terminal. The magnitude of the high-voltage DC voltage output by 271, at this time, the duty cycle of the first power switch Q1 is (1-ζ2).

The rechargeable battery 28 includes two rechargeable batteries B1 and B2 connected in parallel, and the cathode terminal of the rechargeable battery 28 is connected to the ground potential, and the anode terminal provides the terminal voltage Vbat of the rechargeable battery 28 . The standby power detector 291 includes two resistors R1 and R2 connected in series, and one terminal of the standby power detector 291 is connected to the output terminal 20 of the power supply 2 , and the other terminal is connected to the ground potential. The standby power detector 291 divides and samples the voltage through the resistors R1 and R2 to output the standby power detection voltage Vsb' corresponding to the voltage of the standby power Vsb. The battery tester 292 includes two resistors R3 and R4 connected in series, and is connected at one end to the anode terminal of the rechargeable battery 28 and at the other end to ground potential. The battery tester 292 samples through voltage division by resistors R3 and R4 to output a battery test voltage Vbat' corresponding to the terminal voltage Vbat of the rechargeable battery 28.

The bidirectional conversion controller 29 includes a feedback selection circuit (composed of comparator CMP1, AND gate AND1, Zener diodes ZD1 and ZD2, resistors R5～R8, switches Q4 and Q5), subtractor SUB1 (composed of operational amplifier OPA1, resistor R9～R12), adder ADD1 (composed of operational amplifier OPA2, resistors R13～R16), pulse width modulation comparator CMP2 and complementary switch control signal generator (composed of monostable multivibrator OSC1, NOT gate NOT1, XOR gates XOR1 and XOR2, and drivers). Here, assuming that the resistance values of the resistors R9-R12 are the same, the DC voltage V3 output by the subtractor SUB1 is the reference voltage Vref minus the DC voltage V2, that is, V3=Vref-V2; in addition, assuming that the resistance values of the resistors R13-R16 are If they are all the same, the DC voltage V4 output by the adder ADD1 is the DC voltage V1 plus the DC voltage V3, that is, V4=V1+V3, thus, V4=V1-V2+Vref.

When the power switch signal PS is at a high level (or logic 1) to control the power supply 2 to work in the normal mode, when the standby power detection voltage Vsb' is greater than the preset voltage Vset (equivalent to the above-mentioned standby power Vsb voltage being greater than the preset value ), the comparator CMP1 outputs a high level, so that the AND gate AND1 outputs a high level, the control switch Q4 is turned on, and the switch Q5 is turned off, so that the DC voltage V1 is the battery detection voltage Vbat', and the DC voltage V2 is zero voltage, so DC voltage V4=V1-V2+Vref=Vbat'+Vref. The pulse width modulation comparator CMP2 generates a first pulse width modulation signal Vpwm by comparing the ramp voltage Vst with the DC voltage V4. The complementary switching control signal generator generates first complementary switching control signals Vdr1 and Vdr2 according to the first pulse width modulation signal Vpwm, and the duty ratios thereof are ζ1, (1−ζ1) respectively. The first complementary switching control signals Vdr1 and Vdr2 control the switching of the power switches Q1 and Q2, so that the bidirectional power converter 27 is a step-down converter and the power flow flows from the high-voltage terminal 271 to the low-voltage terminal 272, and according to the battery detection voltage Vbat' Feedback to adjust the magnitude of the low-voltage DC voltage output from the low-voltage terminal 272 .

When the power switch signal PS is at a high level (or logic 1) to control the power supply 2 to work in the normal mode, when the standby power detection voltage Vsb' is less than the set voltage Vset (equivalent to the above-mentioned standby power Vsb voltage being less than the preset value ), the comparator CMP1 outputs a low level, so that the AND gate AND1 outputs a low level, the control switch Q4 is turned off, and the switch Q5 is turned on, so that the DC voltage V1 is zero voltage, and the DC voltage V2 is the standby power supply detection voltage Vsb', Therefore, the DC voltage V4=V1-V2+Vref=-Vsb'+Vref. The pulse width modulation comparator CMP2 generates a second pulse width modulation signal Vpwm by comparing the ramp voltage Vst with the DC voltage V4. The complementary switch control signal generator generates second complementary switch control signals Vdr1 and Vdr2 according to the second pulse width modulation signal Vpwm, and their duty ratios are (1-ζ2), ζ2 respectively. The second complementary switching control signals Vdr1 and Vdr2 control the switching of the power switches Q1 and Q2, so that the bidirectional power converter 27 is a boost converter and the power flow flows from the low voltage terminal 272 to the high voltage terminal 271, and detects the voltage Vsb' according to the standby power supply The magnitude feedback is used to adjust the magnitude of the high-voltage DC voltage output from the high-voltage terminal 271 . It should be noted that the purpose of changing the standby power detection voltage Vsb' to (-Vsb') through the subtractor SUB1 is to make the standby power detection voltage Vsb' less than the set voltage Vset momentarily, so that the duty of the switch control signals Vdr1 and Vdr2 Ratio instantly changes from ζ1, (1-ζ1) to reverse phase (1-ζ1), ζ1, so that the bidirectional power converter 27 can be changed from the original buck converter to a boost converter, and then the switch control signal Vdr1 The duty cycle (1-ζ1) and ζ1 of Vdr2 will be adjusted to (1-ζ2), ζ2 due to the size of the standby power detection voltage Vsb'.

When the power switch signal PS is at a low level (or logic 0) to control the power supply 2 to work in the standby mode, no matter what value the comparator CMP1 outputs, the output of the AND gate AND1 will continue to be at a low level, and the control switch Q4 will be turned off. On, the switch Q5 is turned on, so the DC voltage V4=-Vsb'+Vref. The DC voltage V4 passes through the pulse width modulation comparator CMP2 and the complementary switch control signal generator to generate the second switch control signals Vdr1 and Vdr2, whose duty ratios are (1-ζ2) and ζ2 respectively, and make the bidirectional power converter 27 is a boost converter, which converts the terminal voltage Vbat of the rechargeable battery 28 at the low-voltage terminal 272 into a high-voltage DC voltage, and then outputs it from the high-voltage terminal 271 to the output terminal 20, so as to serve as a standby power supply Vsb voltage. At this time, the output power of the standby power converter 24 is almost zero when it is turned off, so there will be no power loss, and relatively no energy will be drawn from the AC power supply Vac. Therefore, in the standby mode, it can be far lower than the existing energy-saving standard. requirements.

FIG. 4 is a timing diagram of signals in the complementary switch control signal generator shown in FIG. 3 . Referring to Figure 3 and Figure 4 at the same time, the monostable multivibrator OSC1 generates dead zone pulses Vp1 and Vp2 according to the pulse width modulation signal Vpwm, wherein the pulse width of the dead zone pulse Vp1 is d1 and the rising edge position corresponds to the pulse width modulation signal The position of the rising edge of Vpwm, and the pulse width of the dead zone pulse Vp2 is d2 and the position of the rising edge corresponds to the position of the falling edge of the pulse width modulation signal Vpwm. The dead zone pulse Vp2 passes through the NOT gate NOT1 to generate an inverted dead zone pulse Vp2. The pulse width modulation signal Vpwm and the dead zone pulse Vp1 pass through the exclusive OR gate XOR1 to generate the switch control signal Vdr1, and the pulse width modulation signal Vpwm and the dead zone pulse Vp2 pass through the exclusive OR gate XOR2 to generate the switch control signal Vdr2. As shown in FIG. 4 , each period T of the pulse width modulation signal Vpwm includes an enabling period Ton and a disabling period Toff, and its duty ratio is Ton/T. The switch control signals Vdr1 and Vdr2 are complementary asymmetric pulse width modulation signals, which control the power switch Q2 to be turned off when the power switch Q1 is turned on, and the power switch Q2 to be turned on when the power switch Q1 is turned off, but in order to avoid the power switch Q1 and Q2 are turned on at the same time, so the dead-time pulses Vp1 and Vp2 are used to make the switch control signals Vdr1 and Vdr2 have dead-times d1 and d2. Since the dead time d1 and d2 are extremely small, when the duty cycle of the switch control signal Vdr1 is ζ1=(Ton-d1)/T≈Ton/T, the duty cycle of the switch control signal Vdr2 is (1-ζ1)=( Toff-d2)/T≈Toff/T.

The power supply device described in the utility model uses a rechargeable battery connected in parallel through a bidirectional power converter at the output end of the standby power converter, and the output end of the standby power converter is connected to the output end of the power supply device for outputting the standby power, so that in In the normal mode, the stability of the standby power supply output by the output terminal of the standby power converter can be improved, and the standby power converter can be turned off in the standby mode, and the bidirectional power converter can provide the standby power, thereby reducing the power loss in the standby mode.

Example 2

The embodiment of the present invention provides a power supply, and FIG. 5 is a block diagram of the power supply according to Embodiment 2 of the present invention.

Referring to Fig. 2 and Fig. 5 at the same time, the power supply 2 is a rechargeable battery 28 connected in parallel through a bidirectional power converter 27 at the output end of the standby power converter 24, and the output end of the standby power converter 24 is directly connected to the power supply 2 output terminal 20; and the power supply 5 is directly connected in parallel with the rechargeable battery 28 at the output terminal of the standby power converter 54, and the output terminal of the standby power converter 54 is connected to the output terminal 50 of the power supply 5 through a boost converter 57 . The working modes of the power supply 5 include normal mode and standby mode, and in both the normal mode and the standby mode, the output terminal 50 of the power supply 5 outputs the standby power Vsb. The power supply 5 includes an EMI filter 21, a bridge rectifier 22, a main power converter 23, a standby power converter 54, a power switch 25, an optional power factor corrector 26, a boost converter 57, a rechargeable battery 28. The standby power detector 291 and the battery detector 292, wherein the components in FIG. 5 with the same symbols as those in FIG. 2 represent components with the same circuit structure, but not limited thereto.

The boost converter 57 has a low voltage terminal 571 and a high voltage terminal 572 , the low voltage terminal 571 is connected to the rechargeable battery 28 , and the high voltage terminal 572 is connected to the output terminal 50 of the power supply 5 . When the standby power converter 54 is in the normal mode, it performs power conversion to convert the DC voltage Vbus into an output voltage and outputs it to the rechargeable battery 28 so as to charge it. 50 output as the standby power supply Vsb voltage. When the standby power converter 54 is in the standby mode and the voltage of the rechargeable battery 28 is sufficient, it stops power conversion and no longer outputs the output voltage. At this time, the rechargeable battery 28 boosts the voltage through the boost converter 57 and outputs it from the output terminal 50. Take it as the standby power supply Vsb voltage. While the standby power converter 54 is in the standby mode and when the voltage of the rechargeable battery 28 is insufficient, it performs power conversion to convert the DC voltage Vbus into an output voltage so as to charge the rechargeable battery 28, and simultaneously outputs to the boost converter 57 to be boosted by it. After voltage is output from the output terminal 50 as the standby power Vsb voltage.

Therefore, the power supply 5 of the present utility model connects the rechargeable battery 28 in parallel to the output end of the standby power converter 54, and the output end of the standby power converter 54 is connected to the output end of the power supply 5 through a boost converter 57 50. Since the rechargeable battery 28 is equivalent to a large capacitor, the standby power Vsb output from the output terminal 50 of the power supply 5 is not likely to change greatly, and the power supply stability of the standby power Vsb is greatly improved. In addition, when the voltage of the rechargeable battery 28 is sufficient in the standby mode, the rechargeable battery 28 can completely provide the standby power supply Vsb through the boost converter 57, so that the input power loss in the standby mode can be far lower than the existing energy-saving specification requirements.

FIG. 6 is a circuit diagram of the power supply shown in FIG. 5, and only the standby power converter 54, boost converter 57, rechargeable battery 28, standby power detector 291 and battery detection in the power supply 5 are described here. The specific circuit of the device 292. Referring to FIG. 6 , the standby power converter 54 adopts the flyback architecture as shown in FIG. 3 , which will not be repeated here. And its control circuit includes resistors R5-R7, switch Q4, AND gate AND1, NOT gate NOT1, comparator CMP1 and a controller connected to power switch Q3. The standby power detector 291 is connected to the output terminal 50 of the power supply 5 for detecting the voltage of the standby power Vsb and outputting a corresponding standby power detection voltage Vsb'. The battery detector 292 is connected to the rechargeable battery 28 for detecting the terminal voltage Vbat of the rechargeable battery 28 and outputting a corresponding battery detection voltage Vbat'. In addition, the resistors R5 and R6 form another battery detector for detecting the terminal voltage Vbat of the rechargeable battery 28 and outputting a feedback signal Vfb to the controller.

When the power supply 5 works in the normal mode, the power switch signal PS is, for example, a high level (or logic 1), which changes to a low level (or logic 0) through the NOT gate NOT1, so that the output of the AND gate AND1 is a low level level, and then the switch Q4 is turned off through the current limiting resistor R7, so the level of the feedback signal Vfb is within an appropriate range, and the controller adjusts the switching of the power switch Q3 according to the magnitude of the feedback signal Vfb, so as to achieve the power of the standby power converter 54 Feedback control, at this time, the standby power converter 54 performs power conversion to output the output voltage to charge the rechargeable battery 28 , and the output voltage is boosted by the boost converter 57 , and then output from the output terminal 50 as the standby power Vsb voltage.

When the power supply 5 is working in the standby mode, the power switch signal PS is, for example, low level, and it becomes high level through the NOT gate NOT1. At this time, the output of the AND gate AND1 is equivalent to being completely determined by the output of the comparator CMP1. . When the voltage of the rechargeable battery 28 is insufficient, in this embodiment, the battery detection voltage Vbat' output by the battery detector 292 is lower than the set voltage Vset, the comparator CMP1 outputs a low level, and the AND gate AND1 outputs a low level, Furthermore, the switch Q4 is turned off, so it is the same as working in the normal mode, that is, the standby power converter 54 will perform power conversion. However, when the voltage of the rechargeable battery 28 is sufficient, in this embodiment, the battery detection voltage Vbat' output by the battery detector 292 is greater than the set voltage Vset, the comparator CMP1 outputs a high level, and the AND gate AND1 outputs a high level. level, and then the switch Q4 is turned on, causing the level of the feedback signal Vfb to be too large, so that the controller stops driving the power switch Q3 to switch. At this time, the standby power converter 54 stops power conversion, and the rechargeable battery 28 converts the power through boost conversion. After the voltage is boosted by the device 57, it is output from the output terminal 50 as the voltage of the standby power supply Vsb.

The boost converter 57 includes an inductor L1, a diode D3 and a power switch Q1, and its control circuit includes a proportional-integral-differential (PID for short) circuit and a pulse width modulation comparator CMP2. The PID circuit is an existing feedback control commonly used in devices whose basic linearity and dynamic characteristics do not change with time. Here, according to the magnitude of the voltage of the standby power supply Vsb (or the detection voltage Vsb' of the standby power supply detected and output by the standby power detector 291 magnitude) through the pulse width modulation comparator CMP2 to control the switching of the power switch Q1 to achieve the feedback control of the boost converter 57 .

The power supply device described in the utility model can be directly connected in parallel with the output end of the standby power converter to be charged, and the output end of the standby power converter is connected to the output end of the power supply device for outputting the standby power through a boost converter, which can improve The standby power supply output by the output terminal of the standby power converter is stable, and when the standby mode and the voltage of the rechargeable battery are sufficient, the standby power converter is turned off and the rechargeable battery provides standby power to reduce power loss in the standby mode.

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present utility model shall be included in this utility model. within the scope of protection of utility models.

Claims (4)

1. A power supply, the working mode of the power supply includes a normal mode and a standby mode, and in the normal mode and the standby mode, the output terminals of the power supply both output standby power, which It is characterized in that the power supply includes: Bridge rectifiers, main power converters, standby power converters, rechargeable batteries, bi-directional power converters and bi-directional conversion controllers; The bridge rectifier is used to convert the voltage input by the AC power supply into a DC voltage; The main power converter, connected to the bridge rectifier, is used to convert the DC voltage into at least one main power voltage output in the normal mode, and stop the conversion in the standby mode; The standby power converter is respectively connected to the output terminal of the power supply and the bridge rectifier, and is used to convert the DC voltage into an output voltage and output it to the power supply in the normal mode. The output terminal of is used as the standby power supply voltage, and stops converting when in the standby mode; The rechargeable battery is respectively connected to the bidirectional power converter and the bidirectional conversion controller; The bidirectional power converter has a high voltage terminal, a low voltage terminal and a control terminal, the high voltage terminal of the bidirectional power converter is connected to the output terminal of the power supply, and the low voltage terminal of the bidirectional power converter is connected to the A rechargeable battery, the control terminal of the bidirectional power converter is connected to the bidirectional conversion controller; The bidirectional conversion controller is respectively connected to the output terminal of the power supply, the rechargeable battery and the control terminal of the bidirectional power converter, and is used to operate in the normal mode and the standby power supply voltage is greater than a predetermined When setting a value, control the bidirectional power converter to convert the standby power supply voltage to charge the rechargeable battery; in the normal mode and when the standby power supply voltage is less than the preset value, control the The bidirectional power converter converts the terminal voltage of the rechargeable battery and transmits it to the output terminal of the power supply to stabilize the standby power supply voltage; and in the standby mode, controls the bidirectional power converter to After the terminal voltage of the rechargeable battery is converted, it is sent to the output terminal of the power supply as the standby power supply voltage. 2. The power supply according to claim 1, wherein the bidirectional power converter comprises: The first power switch has a first terminal, a second terminal and a control terminal, the first terminal of the first power switch is connected to the high-voltage terminal of the bidirectional electric energy converter, and the control terminal of the first power switch is passed through the The control terminal of the bidirectional electric energy converter is connected to the bidirectional conversion controller; The second power switch has a first terminal, a second terminal and a control terminal, the first terminal of the second power switch is connected to the second terminal of the first power switch, and the second terminal of the second power switch connected to ground potential, the control terminal of the second power switch is connected to the bidirectional conversion controller through the control terminal of the bidirectional power converter; an inductor having a first end and a second end, the first end of the inductor is connected to the second end of the first power switch and the first end of the second power switch, the first end of the inductor The two terminals are connected to the low voltage terminal of the bidirectional electric energy converter. 3. The power supply according to claim 2, wherein the bidirectional conversion controller comprises: a feedback selection circuit, connected to the output terminal of the power supply and the rechargeable battery, and used to select the rechargeable battery in the normal mode and the standby power supply voltage is greater than the preset value Terminal voltage feedback; and in the normal mode and the standby power supply voltage is less than the preset value or in the standby mode, select the standby power supply voltage feedback; A pulse width modulation comparator, connected to the feedback selection circuit, used to generate a first pulse width modulation comparator by comparing the ramp voltage with the terminal voltage of the rechargeable battery when the normal mode and the standby power supply voltage are greater than the preset value. a pulse width modulation signal; and in the normal mode and the standby power supply voltage is less than the preset value or in the standby mode, generated by comparing the slope voltage with the inverted standby power supply voltage a second pulse width modulated signal; A complementary switch control signal generator, connected to the pulse width modulation comparator, the control terminal of the first power switch, and the control terminal of the second power switch, for operating in the normal mode and the standby mode When the power supply voltage is greater than the preset value, generate a first complementary switch control signal according to the first pulse width modulation signal; and in the normal mode and when the standby power supply voltage is lower than the preset value or in the In the standby mode, a second complementary switch control signal is generated according to the second pulse width modulation signal. 4. A power supply, the working mode of the power supply includes a normal mode and a standby mode, and in the normal mode and the standby mode, the output terminals of the power supply both output standby power, which It is characterized in that the power supply includes: Bridge rectifiers, main power converters, standby power converters, rechargeable batteries and boost converters; The bridge rectifier is used to convert the voltage input by the AC power supply into a DC voltage; The main power converter, connected to the bridge rectifier, is used to convert the DC voltage into at least one main power voltage output in the normal mode, and stop the conversion in the standby mode; The standby power converter is connected to the bridge rectifier and the rechargeable battery respectively, and is used to convert the DC The voltage is converted into an output voltage and output to the output terminal of the power supply as the standby power supply voltage, and output to the rechargeable battery to charge it; and in the standby mode and the voltage of the rechargeable battery is sufficient, stop conversion; The rechargeable battery is connected to the standby power converter and the boost converter respectively; The boost converter has a high voltage terminal and a low voltage terminal, the high voltage terminal is connected to the output terminal of the power supply, and the low voltage terminal is connected to the rechargeable battery.

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