CN113364296A - Switching power supply circuit and power supply device - Google Patents
Switching power supply circuit and power supply device Download PDFInfo
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- CN113364296A CN113364296A CN202110526000.5A CN202110526000A CN113364296A CN 113364296 A CN113364296 A CN 113364296A CN 202110526000 A CN202110526000 A CN 202110526000A CN 113364296 A CN113364296 A CN 113364296A
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- 239000003990 capacitor Substances 0.000 claims description 37
- 230000006641 stabilisation Effects 0.000 claims 1
- 238000011105 stabilization Methods 0.000 claims 1
- 230000005611 electricity Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 10
- 238000004804 winding Methods 0.000 description 10
- 230000004044 response Effects 0.000 description 4
- 230000009467 reduction Effects 0.000 description 3
- 230000007423 decrease Effects 0.000 description 2
- 238000004146 energy storage Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33561—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having more than one ouput with independent control
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Abstract
The utility model is suitable for a power technical field provides a switching power supply circuit and power supply unit, above-mentioned switching power supply circuit includes first main output unit, supplementary output unit and voltage stabilizing unit, and the input of first main output unit and supplementary output unit's input all are connected with the first secondary coil electricity of transformer, and the voltage stabilizing unit concatenates between first main output unit's output and supplementary output unit's output. When the load of the first main output unit is very small or zero and the load of the auxiliary output unit is increased, the first main output unit provides energy for the auxiliary output unit through the voltage stabilizing unit, so that the second voltage output by the auxiliary output unit is stabilized, and the auxiliary output unit can supply power to the load normally.
Description
Technical Field
The application belongs to the technical field of power supplies, and particularly relates to a switching power supply circuit and a power supply device.
Background
With the increasing precision of electronic products, the electronic products have higher requirements on the energy efficiency and precision of the output voltage of the power supply. In order to meet the requirements of electronic products, current power supply devices can simultaneously provide multiple sets of outputs, such as 12V, 5V, and 3.3V outputs.
The prior art power supply device includes a transformer, a main output unit and an auxiliary output unit, wherein the main output unit and the auxiliary output unit are used for outputting different voltages, for example, the main output unit is used for outputting 12V and 5V voltages, and the auxiliary output unit is used for outputting 3.3V voltage. When the load of the main output unit changes, the feedback system can correspondingly adjust the duty ratio of the PWM, so that the speed of the transformer for changing the output energy is controlled, and the voltage output by the main output unit is ensured to be stable. When the load of the main output unit is small or zero and the load of the auxiliary output unit is increased, the speed of the transformer for outputting energy cannot be changed, so that the voltage output by the auxiliary output unit is reduced, and the load cannot be normally supplied with power.
Disclosure of Invention
The embodiment of the application provides a switching power supply circuit and a power supply device, which can solve the problem of reduction of the output voltage of an auxiliary output unit caused by increase of load.
In a first aspect, an embodiment of the present application provides a switching power supply circuit, including a first main output unit, an auxiliary output unit, and a voltage stabilizing unit, where an input end of the first main output unit and an input end of the auxiliary output unit are both electrically connected to a first secondary coil of a transformer, and the voltage stabilizing unit is connected in series between an output end of the first main output unit and an output end of the auxiliary output unit;
the first main output unit is used for outputting a first voltage, the auxiliary output unit is used for outputting a second voltage, and the first voltage is greater than the second voltage; the voltage drop of the voltage stabilizing unit is equal to the absolute value of the difference between the first voltage and the second voltage, and when the second voltage is reduced, the first main output unit provides energy for the output end of the auxiliary output unit through the voltage stabilizing unit so as to keep the second voltage stable.
In one possible implementation manner of the first aspect, the voltage stabilizing unit includes a plurality of diodes connected in series in sequence;
the anodes of the diodes which are sequentially connected in series are electrically connected with the output end of the first main output unit, and the cathodes of the diodes which are sequentially connected in series are electrically connected with the output end of the auxiliary output unit.
In one possible implementation manner of the first aspect, the first main output unit includes a first rectifying unit, a first inductor, a first capacitor, and a first freewheeling diode;
a first end of the first rectifying unit is electrically connected with a first end of the first secondary coil, and a second end of the first rectifying unit is electrically connected with a first end of the first inductor and a cathode of the first freewheeling diode respectively; a first end of the first capacitor is electrically connected with a second end of the first inductor, and the second end of the first capacitor is respectively connected with an anode of the first freewheeling diode, a second end of the first secondary coil and ground; and the common end of the first inductor and the first capacitor is used as the output end of the first main output unit.
In one possible implementation manner of the first aspect, the first rectifying unit includes a first rectifying diode;
the anode of the first rectifying diode is electrically connected with the first end of the first secondary coil, and the cathode of the first rectifying diode is electrically connected with the first end of the first inductor and the cathode of the first freewheeling diode respectively.
In one possible implementation manner of the first aspect, the auxiliary output unit includes a switching unit, a second rectifying unit, a second inductor, a second capacitor, and a second freewheeling diode;
a first end of the switch unit is electrically connected with a first end of the first secondary coil, and a second end of the switch unit is electrically connected with a first end of the second rectifying unit; a first end of the second inductor is electrically connected with a second end of the second rectifying unit and a cathode of the second freewheeling diode respectively; the first end of the second capacitor is electrically connected with the second end of the second inductor, and the second end of the second capacitor is respectively connected with the anode of the second freewheeling diode, the second end of the first secondary coil and the ground; and the common end of the second inductor and the second capacitor is used as the output end of the auxiliary output unit.
In one possible implementation manner of the first aspect, the switch unit includes a first switch;
the first end of the first switch is electrically connected with the first end of the first secondary coil, and the second end of the first switch is electrically connected with the first end of the second rectifying unit.
In one possible implementation form of the first aspect, the switching unit comprises a magnetic amplifier;
the first end of the magnetic amplifier is electrically connected with the first end of the first secondary coil, and the second end of the magnetic amplifier is electrically connected with the first end of the second rectifying unit.
In one possible implementation manner of the first aspect, the second rectifying unit includes a second rectifying diode;
an anode of the second rectifying diode is electrically connected to the second end of the switching unit, and a cathode of the second rectifying diode is electrically connected to the first end of the second inductor and a cathode of the second freewheeling diode, respectively.
In one possible implementation manner of the first aspect, the switching power supply circuit further includes a second main output unit;
the second main output unit is electrically connected with a second secondary coil of the transformer, and the second main output unit is used for outputting a third voltage.
In a second aspect, an embodiment of the present application provides a power supply apparatus including the switching power supply circuit described in any one of the first aspects.
Compared with the prior art, the embodiment of the application has the advantages that:
when the load of the first main output unit is very small or zero and the load of the auxiliary output unit is increased, the first main output unit provides energy for the auxiliary output unit through the voltage stabilizing unit, so that the auxiliary output unit outputs a stable second voltage, and normal power supply of the load by the auxiliary output unit is ensured.
It is understood that the beneficial effects of the second aspect can be referred to the related description of the first aspect, and are not described herein again.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.
FIG. 1 is a schematic diagram of a prior art switching power supply circuit;
fig. 2 is a schematic diagram of a switching power supply circuit according to an embodiment of the present application;
FIG. 3 is a timing diagram illustrating the operation of a magnetic amplifier according to an embodiment of the present application;
fig. 4 is a schematic diagram of a switching power supply circuit according to another embodiment of the present application.
Detailed Description
In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.
It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
As used in the specification of this application and the appended claims, the term "if" may be interpreted contextually as "when …" or "upon" or "in response to a determination" or "in response to a detection". Similarly, the phrase "if it is determined" or "if a [ described condition or event ] is detected" may be interpreted contextually to mean "upon determining" or "in response to determining" or "upon detecting [ described condition or event ]" or "in response to detecting [ described condition or event ]".
Furthermore, in the description of the present application and the appended claims, the terms "first," "second," "third," and the like are used for distinguishing between descriptions and not necessarily for describing or implying relative importance.
Reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.
Fig. 1 shows a schematic diagram of a switching power supply circuit of the prior art, which includes a main output unit 10 and an auxiliary output unit 20, the main output unit 10 and the auxiliary output unit 20 being electrically connected to the same secondary winding TB of a transformer T. When the load of the main output unit 10 is increased, the first voltage output by the main output unit 10 is reduced, and the feedback system detects that the first voltage is reduced and then increases the duty ratio of the PWM, so as to control the transformer T to increase the output energy rate, so that the first voltage output by the main output unit 10 is kept stable, and the main output unit 10 is ensured to normally supply power to the load.
The feedback system is not able to detect the second voltage output by the auxiliary output unit 20, and therefore, when the load of the auxiliary output unit 20 increases, the transformer T cannot be controlled to adjust the rate of outputting energy, so that the second voltage output by the auxiliary output unit 20 decreases, and the load cannot be normally supplied with power.
In the prior art, in order to solve the problem of voltage reduction of the auxiliary output unit 20 due to load increase, a hypothetical load R11 is added to the main output unit 10. Assuming that the load R11 can cause the feedback system to increase the PWM duty cycle, the transformer T increases the energy output to ensure that the load of the auxiliary output unit 20 is increased within a certain range, and the auxiliary output unit 20 can still normally supply power to the load.
However, the load R11 always consumes energy, which is a problem of wasting energy. Meanwhile, when the load of the auxiliary output unit 20 increases by a value exceeding the preset value, the output voltage of the auxiliary output unit 20 is still reduced, so that the auxiliary output unit 20 cannot normally supply power to the load.
Based on the above problem, an embodiment of the present application provides a switching power supply circuit, which includes a first main output unit, an auxiliary output unit, and a voltage stabilizing unit, where an input end of the first main output unit and an input end of the auxiliary output unit are both electrically connected to a first secondary coil of a transformer, and the voltage stabilizing unit is connected in series between an output end of the first main output unit and an output end of the auxiliary output unit.
When the load of the first main output unit is very small or zero and the load of the auxiliary output unit is increased, the first main output unit provides energy for the auxiliary output unit through the voltage stabilizing unit, so that the auxiliary output unit outputs a stable second voltage, and normal power supply of the load by the auxiliary output unit is ensured.
In order to explain the technical solution described in the present application, the following description will be given by way of specific examples.
Fig. 2 shows a schematic diagram of a switching power supply circuit according to an embodiment of the present application. Referring to fig. 2, the switching power supply circuit includes a first main output unit 100, an auxiliary output unit 200, and a voltage stabilizing unit 300, wherein an input terminal of the first main output unit 100 and an input terminal of the auxiliary output unit 200 are electrically connected to a first secondary winding TB of a transformer T, and the voltage stabilizing unit 300 is connected in series between an output terminal of the first main output unit 100 and an output terminal of the auxiliary output unit 200.
Specifically, the first main output unit 100 outputs a first voltage to power a first load, and the auxiliary output unit 200 outputs a second voltage to power a second load, where the first voltage is greater than the second voltage. The first voltage output by the first main output unit 100 is reduced due to the increase of the first load, the duty ratio of the PWM signal is increased after the feedback system detects the reduction of the first voltage, and the speed of the transformer T for increasing the output energy is controlled, so that the first voltage output by the first main output unit 100 is kept stable, and the first main output unit 100 is ensured to normally supply power to the load.
When the first load of the first main output unit 100 is very small or zero and the second load of the auxiliary output unit 200 increases, the first main output unit 100 supplies energy to the auxiliary output unit 200 through the voltage stabilizing unit 300, so that the auxiliary output unit 200 outputs a stable second voltage, thereby ensuring that the auxiliary output unit 200 can normally supply power to the second load.
In one embodiment of the present application, the voltage stabilizing unit 300 includes a plurality of diodes connected in series in sequence, anodes of the plurality of diodes connected in series in sequence are electrically connected to the output terminal of the first main output unit 100, and cathodes of the plurality of diodes connected in series in sequence are electrically connected to the output terminal of the auxiliary output unit 200.
Specifically, the plurality of diodes connected in series in sequence have a set voltage drop to ensure that the first voltage and the second voltage are both stable. The designer determines the number of diodes used in the voltage stabilizing unit 300 and the type of the diodes used according to actual requirements, so as to meet the requirement that the voltage drop of the voltage stabilizing unit 300 reaches a set value.
For example, as shown in fig. 2, the first voltage output by the first main output unit 100 is 5V (the first voltage output by the first main output unit 100 may also be 12V or other voltages), and the second voltage output by the auxiliary output unit 200 is 3.3V (the second voltage output by the auxiliary output unit 200 may also be other voltages). The voltage stabilizing unit 300 includes a fifth diode D5 and a sixth diode D6, wherein an anode of the fifth diode D5 is electrically connected to the output terminal of the first main output unit 100, a cathode of the fifth diode D5 is electrically connected to an anode of the sixth diode D6, and a cathode of the sixth diode D6 is electrically connected to the output terminal of the auxiliary output unit 200.
The fifth diode D5 and the sixth diode D6 are diodes with a voltage drop of 0.85V or close to 0.85V, so that the voltage drop of the fifth diode D5 and the sixth diode D6 connected in series is 1.7V or close to 1.7V, and the first voltage output by the first main output unit 100 and the second voltage output by the auxiliary output unit 200 are ensured to be stable during operation.
When the first load of the first main output unit 100 is very small or zero and the second load of the auxiliary output unit 200 is large, the second voltage output by the auxiliary output unit 200 is decreased. The output terminal (5V) of the first main output unit 100 supplies energy to the output terminal (3.3V) of the auxiliary output unit 200 through the fifth diode D5 and the sixth diode D6, so that the second voltage output by the auxiliary output unit 200 is stabilized at 3.3V. Meanwhile, as the first main output unit 100 supplies energy to the auxiliary output unit 200, the first voltage (5V) output by the first main output unit 100 is reduced, the feedback system detects that the first voltage is reduced and then increases the duty ratio of PWM, and controls the transformer T to increase the output energy rate, so that the first voltage output by the first main output unit 100 is stabilized at 5V, and it is ensured that the first main output unit 100 supplies power to the first load normally.
Therefore, when the first load of the first main output unit 100 is very small or zero and the second load of the auxiliary output unit 200 is large, the auxiliary output unit 200 can still output a stable second voltage to normally supply power to the second load.
In one embodiment of the present application, the first main output unit 100 includes a first rectifying unit 101, a first inductor L1, a first capacitor C1, and a first freewheeling diode D2. A first terminal of the first rectifying unit 101 is electrically connected to a first terminal of the first secondary coil TB, and a second terminal of the first rectifying unit 101 is electrically connected to a first terminal of the first inductor L1 and a cathode of the first freewheeling diode D2, respectively. A first end of the first capacitor C1 is electrically connected with a second end of the first inductor L1, and a second end of the first capacitor C1 is electrically connected with the anode of the first freewheeling diode D2, the second end of the first secondary winding TB, and ground, respectively; the common terminal of the first inductor L1 and the first capacitor C1 serves as an output terminal of the first main output unit 100.
Specifically, the first rectifying unit 101 rectifies the electrical signal output by the first secondary coil TB of the transformer T, and the first inductor L1 and the first capacitor C1 are energy storage devices. When the output of the first rectifying unit 101 is at a pulse high level, the first capacitor C1 and the first inductor L1 store energy, and the first main output unit 100 outputs a first voltage. When the output of the first rectifying unit 101 is at a pulse low level, the first capacitor C1 and the first inductor L1 release energy, so that the first main output unit 100 outputs a first voltage. Thereby, the first main output unit 100 can continuously output the stable first voltage.
When the first capacitor C1 and the first inductor L1 discharge energy, the first freewheeling diode D2 may function to prevent sudden voltage changes in the circuit, thereby functioning to protect the circuit.
Illustratively, the first rectifying unit 101 includes a first rectifying diode D1, an anode of the first rectifying diode D1 is electrically connected to the first end of the first secondary coil TB, and a cathode of the first rectifying diode D1 is electrically connected to the first end of the first inductor L1 and the cathode of the first freewheeling diode D2, respectively.
Specifically, the first rectifying diode D1 may perform half-wave rectification on the electrical signal output from the first secondary coil TB of the transformer T, and in cooperation with the following first inductor L1 and first capacitor C1, the first main output unit 100 may be implemented to output a stable first voltage.
In one embodiment of the present application, the auxiliary output unit 200 includes a switching unit 201, a second rectifying unit 202, a second inductor L2, a second capacitor C2, and a second freewheeling diode D4. A first terminal of the switching unit 201 is electrically connected to a first terminal of the first secondary coil TB, and a second terminal of the switching unit 201 is electrically connected to a first terminal of the second rectifying unit 202. A first terminal of the second inductor L2 is electrically connected to a second terminal of the second rectifying unit 202 and a cathode of the second freewheeling diode D4, respectively. A first terminal of the second capacitor C2 is electrically connected to the second terminal of the second inductor L2, and a second terminal of the second capacitor C2 is electrically connected to the anode of the second freewheeling diode D4, the second terminal of the first secondary winding TB, and ground, respectively. The common terminal of the second inductor L2 and the second capacitor C2 serves as an output terminal of the auxiliary output unit 200.
Specifically, the auxiliary output unit 200 may be controlled by the switching unit 201, and when the switching unit 201 is in a conducting state, the auxiliary output unit 200 normally outputs the second voltage; when the switching unit 201 is in an off state, the auxiliary output unit 200 does not output.
The second rectifying unit 202 rectifies the electrical signal output by the first secondary winding TB of the transformer T, and the second inductor L2 and the second capacitor C2 are energy storage devices. When the output of the second rectifying unit 202 is at a pulse high level, the second capacitor C2 and the second inductor L2 store energy, and the auxiliary output unit 200 outputs a second voltage. When the output of the second rectifying unit 202 is at a pulse low level, the second capacitor C2 and the second inductor L2 release energy, so that the auxiliary output unit 200 outputs a second voltage. Thereby, the auxiliary output unit 200 can continuously output the stable second voltage.
When the second capacitor C2 and the second inductor L2 discharge energy, the second freewheeling diode D4 can function to prevent sudden voltage changes in the circuit, thereby functioning to protect the circuit.
Illustratively, the switching unit 201 includes a first switch, a first terminal of which is electrically connected to a first terminal of the first secondary coil TB, and a second terminal of which is electrically connected to a first terminal of the second rectifying unit 202.
Specifically, the auxiliary output unit 200 may be controlled to output the second voltage by controlling the first switch. The first switch can be a switching tube, such as a MOS tube.
Illustratively, the switching unit 201 includes a magnetic amplifier MA1, a first terminal of the magnetic amplifier MA1 is electrically connected to a first terminal of the first secondary winding TB, and a second terminal of the magnetic amplifier MA1 is electrically connected to a first terminal of the second rectifying unit 202.
Specifically, the magnetic amplifier MA1 is made by winding a coil on a magnetic core with a square hysteresis loop, and its operating state includes a saturated state and a non-saturated state, and the output voltage is controlled by reducing the duty ratio of the voltage pulse. The magnetic amplifier MA1 can reduce the mutual influence between the first main output unit 100 and the auxiliary output unit 200, and ensure that the first main output unit 100 and the auxiliary output unit 200 can output voltage signals normally.
Fig. 3 shows an operation timing diagram of the magnetic amplifier MA1 according to an embodiment of the present application. Referring to fig. 3, TB is a waveform diagram of the first secondary winding TB of the transformer T, and MA is a waveform diagram of the second terminal of the magnetic amplifier MA 1. When the first secondary coil TB of the transformer T is at a pulse high level, the magnetic amplifier MA1 is in an unsaturated state within a time T1, and at this time, the second end of the magnetic amplifier MA1 is at a pulse low level; during time t2, the magnetic amplifier MA1 is in saturation, and the second terminal of the magnetic amplifier MA1 is pulsed high. The auxiliary output unit 200 can be ensured to stably output the second voltage by adjusting the initial magnetic flux density of the magnetic amplifier MA1 to adjust the time when the magnetic amplifier MA1 is in the saturation state t 2.
Illustratively, the second rectifying unit 202 includes a second rectifying diode D3, an anode of the second rectifying diode D3 is electrically connected to the second terminal of the switching unit 201, and a cathode of the second rectifying diode D3 is electrically connected to the first terminal of the second inductor L2 and the cathode of the second freewheeling diode D4, respectively.
Specifically, the second rectifying diode D3 may perform half-wave rectification on the electrical signal output from the first secondary coil TB of the transformer T, and the auxiliary output unit 200 may output a stable second voltage in cooperation with the following second inductor L2 and second capacitor C2.
Fig. 4 shows a schematic diagram of a switching power supply circuit according to another embodiment of the present application. Referring to fig. 4, the switching power supply circuit further includes a second main output unit 400, the second main output unit 400 being electrically connected to the second secondary winding TC of the transformer T, the second main output unit 400 being configured to output a third voltage.
Specifically, the second main output unit 400 and the first main output unit 100 can provide voltages with different magnitudes to meet the requirements of the electronic system for outputting various voltages.
In one embodiment of the present application, the second main output unit 400 includes a third rectifying diode D7, a third freewheeling diode D8, a third inductor L3, and a third capacitor C3. An anode of the third rectifying diode D7 is electrically connected to one end of the second secondary coil TC, and a cathode of the third rectifying diode D7 is electrically connected to a cathode of the third freewheeling diode D8 and a first end of the third inductor L3, respectively. A first terminal of the third capacitor C3 is electrically connected to the second terminal of the third inductor L3, and a second terminal of the third capacitor C3 is electrically connected to the anode of the third freewheeling diode D8, the second terminal of the second secondary winding TC, and ground, respectively.
The second main output unit 400 outputs a third voltage through the second secondary coil TC connected to the transformer T, wherein the third voltage is not equal to the first voltage, so that the first main output unit 100 and the second main output unit 400 can output different voltages, and the requirements of the electronic system on different voltages are met.
Illustratively, as shown in fig. 4, the first voltage output by the first main output unit 100 is 5V, the third voltage output by the second main output unit 400 is 12V, and the second voltage output by the auxiliary output unit 200 is 3.3V. When the loads of the first main output unit 100 and the second main output unit 400 are both small or zero and the load of the auxiliary output unit 200 is large, the first main output unit 100 provides energy for the auxiliary output unit 200 through the voltage regulation unit 300. Since the energy output from the first main output unit 100 increases, the voltage at the output terminal thereof decreases. After the feedback system detects that the voltage at the output end of the first main output unit 100 is reduced, the duty ratio of the PWM signal is increased, so that the transformer T increases the energy output rate, and thus the first main output unit 100 and the auxiliary output unit 200 maintain stable voltage output, and at this time, the auxiliary output unit 200 can normally supply power to the load.
The application also discloses a power supply device which comprises the switching power supply circuit. When the first load of the first main output unit 100 is very small or zero and the second load of the auxiliary output unit 200 increases, the first main output unit 100 supplies energy to the auxiliary output unit 200 through the voltage stabilizing unit 300, so as to ensure the stability of the second voltage output by the auxiliary output unit 200, thereby ensuring that the auxiliary output unit 200 can normally supply power to the second load.
The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.
Claims (10)
1. A switching power supply circuit is characterized by comprising a first main output unit, an auxiliary output unit and a voltage stabilizing unit, wherein the input end of the first main output unit and the input end of the auxiliary output unit are electrically connected with a first secondary coil of a transformer, and the voltage stabilizing unit is connected between the output end of the first main output unit and the output end of the auxiliary output unit in series;
the first main output unit is used for outputting a first voltage, the auxiliary output unit is used for outputting a second voltage, and the first voltage is greater than the second voltage; the voltage drop of the voltage stabilizing unit is equal to the absolute value of the difference between the first voltage and the second voltage, and when the second voltage is reduced, the first main output unit provides energy for the output end of the auxiliary output unit through the voltage stabilizing unit so as to keep the second voltage stable.
2. The switching power supply circuit according to claim 1, wherein the voltage stabilization unit includes a plurality of diodes connected in series in sequence;
the anodes of the diodes which are sequentially connected in series are electrically connected with the output end of the first main output unit, and the cathodes of the diodes which are sequentially connected in series are electrically connected with the output end of the auxiliary output unit.
3. The switching power supply circuit according to claim 1, wherein the first main output unit includes a first rectifying unit, a first inductor, a first capacitor, and a first freewheeling diode;
a first end of the first rectifying unit is electrically connected with a first end of the first secondary coil, and a second end of the first rectifying unit is electrically connected with a first end of the first inductor and a cathode of the first freewheeling diode respectively; a first end of the first capacitor is electrically connected with a second end of the first inductor, and the second end of the first capacitor is respectively connected with an anode of the first freewheeling diode, a second end of the first secondary coil and ground; and the common end of the first inductor and the first capacitor is used as the output end of the first main output unit.
4. The switching power supply circuit according to claim 3, wherein the first rectifying unit includes a first rectifying diode;
the anode of the first rectifying diode is electrically connected with the first end of the first secondary coil, and the cathode of the first rectifying diode is electrically connected with the first end of the first inductor and the cathode of the first freewheeling diode respectively.
5. The switching power supply circuit according to claim 1, wherein the auxiliary output unit includes a switching unit, a second rectifying unit, a second inductor, a second capacitor, and a second freewheeling diode;
a first end of the switch unit is electrically connected with a first end of the first secondary coil, and a second end of the switch unit is electrically connected with a first end of the second rectifying unit; a first end of the second inductor is electrically connected with a second end of the second rectifying unit and a cathode of the second freewheeling diode respectively; the first end of the second capacitor is electrically connected with the second end of the second inductor, and the second end of the second capacitor is respectively connected with the anode of the second freewheeling diode, the second end of the first secondary coil and the ground; and the common end of the second inductor and the second capacitor is used as the output end of the auxiliary output unit.
6. The switching power supply circuit according to claim 5, wherein the switching unit includes a first switch;
the first end of the first switch is electrically connected with the first end of the first secondary coil, and the second end of the first switch is electrically connected with the first end of the second rectifying unit.
7. The switching power supply circuit according to claim 5, wherein the switching unit includes a magnetic amplifier;
the first end of the magnetic amplifier is electrically connected with the first end of the first secondary coil, and the second end of the magnetic amplifier is electrically connected with the first end of the second rectifying unit.
8. The switching power supply circuit according to claim 5, wherein the second rectifying unit includes a second rectifying diode;
an anode of the second rectifying diode is electrically connected to the second end of the switching unit, and a cathode of the second rectifying diode is electrically connected to the first end of the second inductor and a cathode of the second freewheeling diode, respectively.
9. The switching power supply circuit according to any one of claims 1 to 8, further comprising a second main output unit;
the second main output unit is electrically connected with a second secondary coil of the transformer, and the second main output unit is used for outputting a third voltage.
10. A power supply apparatus comprising the switching power supply circuit according to any one of claims 1 to 9.
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| CN202110526000.5A CN113364296A (en) | 2021-05-14 | 2021-05-14 | Switching power supply circuit and power supply device |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1262551A (en) * | 2000-01-13 | 2000-08-09 | 深圳市华为电气股份有限公司 | Dual-output power supply with high voltage stability and high precision |
| CN102377347A (en) * | 2011-10-17 | 2012-03-14 | 广州三晶电气有限公司 | Flyback converter for implementing auxiliary output voltage control by using triode and control method |
| CN105075092A (en) * | 2013-11-14 | 2015-11-18 | 崇实大学校产学协力团 | Multi-output converter and control method therefor |
| CN105790589A (en) * | 2016-03-08 | 2016-07-20 | 马鞍山职业技术学院 | Multi-output switching converter with high efficiency and high accuracy |
| CN107846147A (en) * | 2017-11-07 | 2018-03-27 | 上海电力学院 | A kind of single input and multi-output DC DC switch converters |
| CN207442703U (en) * | 2017-12-06 | 2018-06-01 | 深圳市科华恒盛科技有限公司 | A kind of circuit and accessory power supply of the cross regulation rate for improving accessory power supply |
| CN109980943A (en) * | 2019-04-08 | 2019-07-05 | 北京承力电源有限公司 | A kind of two-way voltage-stabilizing Switching Power Supply of the voltage superposition based on magnetic amplifier |
-
2021
- 2021-05-14 CN CN202110526000.5A patent/CN113364296A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1262551A (en) * | 2000-01-13 | 2000-08-09 | 深圳市华为电气股份有限公司 | Dual-output power supply with high voltage stability and high precision |
| CN102377347A (en) * | 2011-10-17 | 2012-03-14 | 广州三晶电气有限公司 | Flyback converter for implementing auxiliary output voltage control by using triode and control method |
| CN105075092A (en) * | 2013-11-14 | 2015-11-18 | 崇实大学校产学协力团 | Multi-output converter and control method therefor |
| CN105790589A (en) * | 2016-03-08 | 2016-07-20 | 马鞍山职业技术学院 | Multi-output switching converter with high efficiency and high accuracy |
| CN107846147A (en) * | 2017-11-07 | 2018-03-27 | 上海电力学院 | A kind of single input and multi-output DC DC switch converters |
| CN207442703U (en) * | 2017-12-06 | 2018-06-01 | 深圳市科华恒盛科技有限公司 | A kind of circuit and accessory power supply of the cross regulation rate for improving accessory power supply |
| CN109980943A (en) * | 2019-04-08 | 2019-07-05 | 北京承力电源有限公司 | A kind of two-way voltage-stabilizing Switching Power Supply of the voltage superposition based on magnetic amplifier |
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