[go: up one dir, main page]

CN114172379A - A switching power supply device and its control method - Google Patents

A switching power supply device and its control method Download PDF

Info

Publication number
CN114172379A
CN114172379A CN202111458977.4A CN202111458977A CN114172379A CN 114172379 A CN114172379 A CN 114172379A CN 202111458977 A CN202111458977 A CN 202111458977A CN 114172379 A CN114172379 A CN 114172379A
Authority
CN
China
Prior art keywords
power supply
voltage
module
circuit
switch tube
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202111458977.4A
Other languages
Chinese (zh)
Inventor
高小丽
张岩
霍星星
郭立星
刘蓝田
雷龙
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Gree Electric Appliances Inc of Zhuhai
Original Assignee
Gree Electric Appliances Inc of Zhuhai
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gree Electric Appliances Inc of Zhuhai filed Critical Gree Electric Appliances Inc of Zhuhai
Priority to CN202111458977.4A priority Critical patent/CN114172379A/en
Publication of CN114172379A publication Critical patent/CN114172379A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • 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
    • 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
    • H02M1/00—Details of apparatus for conversion
    • H02M1/42—Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
    • H02M1/4208—Arrangements for improving power factor of AC input
    • H02M1/4225—Arrangements for improving power factor of AC input using a non-isolated boost converter
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)
  • Rectifiers (AREA)

Abstract

The invention discloses a switching power supply device and a control method thereof, wherein the device comprises: a PFC circuit and a forward power circuit; the forward power supply circuit is arranged at a PFC inductor of the PFC circuit; the forward power supply circuit includes: a high-frequency transformer and a rectifier switch tube module; the primary winding of the high-frequency transformer is used as the input end of the forward power supply circuit; the dotted end of the secondary winding of the high-frequency transformer is connected to the control end of the rectifier switch tube module; the first connecting end of the rectifier switch tube module is used as the output end of the forward power circuit and can output power supply voltage to the first end of a load; and the synonym end of the secondary winding of the high-frequency transformer is connected to the second connecting end of the rectifier switch tube module. This scheme, through making the rectifier tube of just swashing power output, adopt the switch tube to carry out the rectification, can reduce the loss of just swashing power output.

Description

Switching power supply device and control method thereof
Technical Field
The invention belongs to the technical field of power supplies, particularly relates to a switching power supply device and a control method thereof, and particularly relates to a novel isolating switching power supply circuit and a control method thereof.
Background
A flyback power supply in an isolated switch power supply circuit topology is generally applied to a low-power supply conversion occasion, and a forward power supply is adopted in a commercial air conditioner due to the large requirement on the load capacity. And a rectifier tube at the output end of the forward power supply adopts a rectifier diode for rectification. However, the conduction voltage drop of the rectifier diode is higher, so that the loss of the output end rectifier tube is more outstanding.
The above is only for the purpose of assisting understanding of the technical aspects of the present invention, and does not represent an admission that the above is prior art.
Disclosure of Invention
The invention aims to provide a switching power supply device and a control method thereof, which aim to solve the problem that when a rectifier tube at the output end of a forward power supply in an isolated switching power supply circuit topology is rectified by a rectifier diode, the conduction voltage drop of the rectifier diode is higher, so that the loss of the rectifier tube at the output end of the forward power supply is larger, and achieve the effect of reducing the loss of the output end of the forward power supply by rectifying the rectifier tube at the output end of the forward power supply by a switching tube.
The present invention provides a switching power supply device, including: a PFC circuit and a forward power circuit; the forward power supply circuit is arranged at a PFC inductor of the PFC circuit; the forward power supply circuit includes: a high-frequency transformer and a rectifier switch tube module; the primary winding of the high-frequency transformer is used as the input end of the forward power supply circuit; the dotted end of the secondary winding of the high-frequency transformer is connected to the control end of the rectifier switch tube module; the first connecting end of the rectifier switch tube module is used as the output end of the forward power circuit and can output power supply voltage to the first end of a load; and the synonym end of the secondary winding of the high-frequency transformer is connected to the second connecting end of the rectifier switch tube module.
In some embodiments, the PFC circuit includes: a PFC inductance; and the primary winding of the high-frequency transformer is used as a PFC inductor of the PFC circuit.
In some embodiments, the PFC circuit further comprises: the power supply comprises a power supply switch tube module, a power supply diode module and a bus capacitor module; the control end of the power switching tube module is used as the input end of a driving signal of the switching power supply device; the first connecting end of the power switch tube module is connected to the synonym end of the primary winding of the high-frequency transformer; the first connecting end of the power switch tube module is also connected to the anode of the power diode module; the second connecting end of the power switch tube module is grounded; and the cathode of the power diode module is grounded after passing through the bus capacitor module.
In some embodiments, the power switching tube module includes: a first MOS transistor; the control end of the power switch tube module is the grid electrode of the first MOS tube; the first connecting end of the power switch tube module is the drain electrode of the first MOS tube; the second connecting end of the power switch tube module is the source electrode of the first MOS tube.
In some embodiments, the forward power supply circuit further comprises: the follow current switch tube module and the energy storage inductor module; the synonym end of a secondary winding of the high-frequency transformer is connected to the control end of the follow current switching tube module; the dotted end of the secondary winding of the high-frequency transformer is also connected to the first connecting end of the follow current switch tube module; the second connecting end of the follow current switching tube module is connected to the first connecting end of the rectification switching tube module; the energy storage inductance module is arranged at the first connecting end of the follow current switch tube module and is connected with the second end of the load.
In some embodiments, the forward power supply circuit further comprises: a filtering module; the filtering module is arranged between the first end of the load and the second end of the load.
In some embodiments, the rectifier switching tube module includes: a second MOS transistor; the control end of the rectifier switch tube module is the grid electrode of the second MOS tube; the first connecting end of the rectifier switch tube module is the drain electrode of the second MOS tube; the second connecting end of the rectifier switch tube module is a source electrode of the second MOS tube; the follow current switch tube module comprises: a third MOS transistor; the control end of the follow current switch tube module is the grid electrode of the third MOS tube; the first connecting end of the follow current switch tube module is the drain electrode of the third MOS tube; and the second connecting end of the follow current switch tube module is a source electrode of the third MOS tube.
In accordance with another aspect of the present invention, there is provided a method for controlling a switching power supply apparatus, including: acquiring bus voltage of the PFC circuit, PFC current of the PFC circuit and output voltage of the forward power circuit; determining a driving signal of the PFC circuit according to the bus voltage of the PFC circuit, the PFC current of the PFC circuit and the output voltage of the forward power supply circuit; and controlling the switching power supply device to work according to the driving signal of the PFC circuit so as to convert high voltage provided by an input power supply of the PFC circuit into low voltage and supply power to the load.
In some embodiments, determining the driving signal of the PFC circuit according to a bus voltage of the PFC circuit, a PFC current of the PFC circuit, and an output voltage of the forward power supply circuit includes: performing voltage regulation according to the output voltage of the forward power supply circuit and the given value of the output voltage to obtain a first voltage regulation value; performing voltage regulation according to the bus voltage of the PFC circuit and a bus voltage reference value to obtain a second voltage regulation value; obtaining a first voltage by a divider according to the sum of the first voltage regulating value and the second voltage regulating value and a voltage value corresponding to the PFC current of the PFC circuit; and comparing the first voltage with a preset carrier voltage to obtain a comparison voltage, and taking the comparison voltage as the driving signal.
Therefore, according to the scheme of the invention, the output end of the forward power supply is positively excited in the topology of the isolated switch power supply circuit, so that the loss of the output end of the forward power supply can be reduced by rectifying the rectifying tube of the output end of the forward power supply by adopting the switch tube.
Furthermore, the scheme of the invention adopts a rectification switch tube (such as an MOS tube) to replace a rectification diode and adopts a follow current switch tube (such as an MOS tube) to replace a follow current diode in the forward power output end of the isolating switch power circuit topology, thereby not only reducing the loss of the forward power output end, but also realizing self-driving on the secondary side of the high-frequency transformer by using the switch tube to carry out rectification and follow current at the forward power output end, independently operating without depending on the primary side topology and greatly simplifying the circuit design.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.
Drawings
Fig. 1 is a schematic structural diagram of a switching power supply device according to an embodiment of the invention;
fig. 2 is a schematic structural diagram of a topology circuit of a power supply of a home appliance in a related scheme;
FIG. 3 is a schematic diagram of a power supply topology according to an embodiment of the present invention;
fig. 4 is a flowchart illustrating a control method of the switching power supply apparatus according to an embodiment of the invention;
fig. 5 is a flowchart illustrating an embodiment of determining a driving signal of the PFC circuit according to the method of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
According to an embodiment of the present invention, there is provided a switching power supply device. Referring to fig. 1, a schematic structural diagram of an embodiment of a switching power supply device according to the present invention is shown. The switching power supply device may include: a PFC circuit and a forward power supply circuit. The forward power circuit is disposed at a PFC inductor of the PFC circuit, such as a cathode of a diode D in the PFC circuit shown in fig. 3, i.e., at a point P. The forward power supply circuit includes: high-frequency transformer and rectifier switch tube module. A high frequency transformer, such as high frequency transformer T1. And a rectification switching tube module, such as a MOS tube Q3.
And the primary winding of the high-frequency transformer is used as the input end of the forward power supply circuit. And the dotted terminal of the secondary winding of the high-frequency transformer is connected to the control terminal of the rectifier switching tube module (such as the grid of a MOS tube Q3). The first connection end (such as the drain electrode of the MOS transistor Q3) of the rectifier switching tube module is used as the output end of the forward power circuit, and can output the supply voltage to the first end of the load. And the synonym terminal of the secondary winding of the high-frequency transformer is connected to the second connecting terminal (such as the source electrode of the MOS transistor Q3) of the rectifier switching tube module.
Fig. 2 is a schematic structural diagram of a topology circuit of a power supply of a home appliance in a related scheme. As shown in fig. 2, the topology circuit of the household electrical appliance power supply includes: inductor L, inductor L1, MOS pipe Q1, MOS pipe Q2, diode D1, diode D2, capacitor C1, transformer T1, Main Control Unit (MCU), and analog power IC (i.e. analog power chip).
The topology circuit of the power supply of the household electrical appliance shown in fig. 2 has 1 output as an example, and comprises: a BOOST PFC circuit composed of an inductor L, MOS, a Q2, and a diode D, and a forward power circuit composed of a bus capacitor, such as a capacitor C, a high frequency transformer T1, a power switching transistor, such as a MOS transistor Q1 (some analog power ICs have switching transistors built in), a rectifier diode, such as a diode D1, a freewheeling diode, such as a diode D2, a filter capacitor, such as a capacitor C1, and a filter inductor having an energy storage function, such as an inductor L1.
In the example shown in fig. 2, the primary winding of the high frequency transformer T1 is fed from the bus capacitor (e.g., capacitor C) behind the PFC circuit, and the power switch tube (e.g., MOS tube) is connected to the bus capacitorWhen Q1 is turned on, diode D1 is turned on, and when power is supplied to load 1, inductor L1 and capacitor C1 store electric energy, and diode D2 is turned off. When a power switch transistor, such as a MOS transistor Q1, is turned off, the diode D1 is turned off, the diode D2 is turned on, and the energy stored in the inductor L1 and the capacitor C1 supplies power to the load 1 through the diode D2, so as to maintain the output voltage unchanged. The required low-voltage direct current is supplied to the load 1 by controlling a power switch tube such as an MOS tube Q1 through the original secondary side turn ratio N1/N2 setting of a high-frequency transformer T1 and an analog power supply IC. A main control unit capable of detecting the current I of the PFC circuit according to the current sensorPFCAnd bus voltage V detected by the voltage sensorpAnd (5) controlling.
In the example shown in fig. 2, after the power factor correction, the bus gets power, and the multiple outputs are realized through the forward topology of the power IC (i.e., the power chip) and the high-frequency transformer, which can show the advantages especially in a system with low voltage and large current. However, since the conduction voltage drop of the rectifier diode is relatively high and the loss of the output-side rectifier tube is more prominent, this problem needs to be considered in the design of the isolated switching power supply circuit.
The scheme of the invention provides a novel isolating switch power supply circuit and a control method thereof, which utilize an MOS (metal oxide semiconductor) tube to replace a rectifier diode at the output end of a forward power supply, reduce the conduction loss of a new circuit topology, improve the circuit efficiency, reduce the conduction loss of the diode in the isolating switch power supply circuit, improve the efficiency of the isolating switch power supply circuit, and solve the problems that the conduction voltage drop of the rectifier diode is higher and the loss of a rectifier tube at the output end is more, namely, the problem that when the rectifier tube at the output end of the forward power supply in the isolating switch power supply circuit topology is rectified by adopting the rectifier diode, the conduction voltage drop of the rectifier diode is higher, so that the loss of the rectifier tube at the output end of the forward power supply is larger.
In some embodiments, the PFC circuit includes: a PFC inductance. And the primary winding of the high-frequency transformer is used as a PFC inductor of the PFC circuit.
Considering that with the advancement of digital power supply technology, modern household electrical appliance controller power supplies are developed to be digital, high-frequency, small and high-efficiency, the hardware cost also needs to be significantly reduced. According to the scheme of the invention, the PFC (power factor correction) inductor is used as the primary side of the high-frequency transformer, so that the cost of the controller is effectively reduced, the area of a PCB (printed circuit board) is reduced, the problems of large area and high manufacturing cost of the PCB of the switching power supply in related schemes are solved, the hardware cost of the switching power supply is obviously reduced, and the stability of output voltage is improved.
In some embodiments, the PFC circuit further comprises: the power supply comprises a power supply switch tube module, a power supply diode module and a bus capacitor module. And the power switching tube module is a MOS tube Q1. A power diode module, such as diode D. And a bus capacitor module, such as a capacitor C.
The control terminal of the power switching transistor module (e.g. the gate of the MOS transistor Q1) is used as the input terminal of the driving signal of the switching power supply device. The first connection end (for example, the drain of the MOS transistor Q1) of the power switching transistor module is connected to the different-name end of the primary winding of the high-frequency transformer. The first connection terminal of the power switch module (for example, the drain of the MOS transistor Q1) is further connected to the anode of the power diode module. And the second connecting end (such as the source electrode of the MOS transistor Q1) of the power switch tube module is grounded. And the cathode of the power diode module is grounded after passing through the bus capacitor module.
Fig. 3 is a schematic structural diagram of a power supply topology circuit according to an embodiment of the present invention. The power supply topology circuit shown in fig. 3 is a new power supply circuit improved on the basis of the power supply topology circuit shown in fig. 2. In the example shown in fig. 3, a diode in a forward circuit in the related scheme is replaced by a MOS transistor on the basis of taking a PFC (power factor correction) inductor as the primary side of the high-frequency transformer T1, and the secondary side of the high-frequency transformer T1 is self-driven and can be operated independently without depending on the primary side topology.
In some embodiments, the power switching tube module includes: the first MOS transistor, for example, the MOS transistor Q1. And the control end of the power switch tube module is the grid electrode of the first MOS tube. The first connecting end of the power switch tube module is the drain electrode of the first MOS tube. The second connecting end of the power switch tube module is the source electrode of the first MOS tube.
The power supply topology circuit shown in fig. 3, for example, has 1 output, which includes: a BOOST PFC circuit consisting of a tube Q1 of a primary inductor L, MOS of a transformer T1 and a diode D, and a forward power circuit.
In some embodiments, the forward power supply circuit further comprises: the device comprises a follow current switch tube module and an energy storage inductance module. And a freewheeling switching tube module, such as a MOS tube Q4. And an energy storage inductance module, such as an inductor L1.
The synonym terminal of the secondary winding of the high-frequency transformer is connected to the control terminal of the freewheeling switching tube module (such as the gate of the MOS transistor Q4). The dotted terminal of the secondary winding of the high-frequency transformer is also connected to the first connection terminal (such as the drain of the MOS transistor Q4) of the freewheeling switching transistor module. The second connection end (such as the source electrode of the MOS transistor Q4) of the follow current switching tube module is connected to the first connection end (such as the drain electrode of the MOS transistor Q3) of the rectification switching tube module.
The energy storage inductance module is arranged at a first connection end (such as a drain electrode of a MOS transistor Q4) of the follow current switching tube module and is connected with a second end of the load.
In the scheme of the invention, the secondary side of the transformer adopts self-driving, and the transformer can independently operate without depending on primary side topology, thereby greatly simplifying circuit design.
In the example shown in fig. 3, a PFC inductor and a high-frequency transformer T1 are integrated into one, a primary inductor L of the high-frequency transformer T1 serves as the PFC inductor, a switching tube of the PFC circuit, i.e., a power switching tube such as Q1, functions as a switching tube in a forward power supply, and a MOS tube with an extremely low on-resistance is used for synchronous rectification instead of a rectifier diode, so that the circuit loss is reduced, and the circuit efficiency is improved. The Main Control Unit (MCU) is used for controlling the MOS tube Q1 and the MOS tube Q3, synchronous rectification is achieved, an analog power supply IC and a PFC inductor are omitted, the cost of the controller is effectively reduced, and the area of a PCB is reduced.
In the example shown in fig. 3, when the MOS transistor Q1 on the primary side of the high-frequency transformer T1 is turned on, the input power of the high-frequency transformer T1 charges the PFC inductor L, and the voltage across the PFC inductor L is positive and negative, and when the MOS transistor Q3 is turned off, the input power of the high-frequency transformer T1 and the PFC inductor L simultaneously charge the capacitor C, and at this time, the voltage across the PFC inductor L is positive and negative, and an interleaved voltage can be formed across the PFC inductor L. Under the action of the high-frequency transformer T1, the PFC inductance L, namely the energy of the primary side of the high-frequency transformer T1, is transferred to the secondary side of the high-frequency transformer T1, and due to the fact that the high-frequency transformer T1 is a forward circuit, the secondary voltage of the high-frequency transformer T1 is in phase with the primary side voltage of the high-frequency transformer T1, namely the voltage of the PFC inductance L, and in the positive half cycle of the secondary voltage of the high-frequency transformer T1, the MOS tube Q3 has a rectifying effect. In the negative half cycle, the MOS transistor Q3 is turned off, the MOS transistor Q4 is turned on, and the MOS transistor Q4 performs a freewheeling function.
In some embodiments, the forward power supply circuit further comprises: a filtering module, such as a capacitor C1.
The filtering module is arranged between the first end of the load and the second end of the load.
As shown in fig. 3, the power supply topology circuit includes: inductor L1, MOS pipe Q1, MOS pipe Q3, MOS pipe Q4, diode D, electric capacity C1, high frequency transformer T1, and Main Control Unit (MCU).
In some embodiments, in the PFC circuit, when the power switch module is an MOS transistor, the rectifier switch module is an MOS transistor, and the freewheeling switch module is an MOS transistor, the control end of each switch module is a gate of the MOS transistor, the first connection end of each switch module is a drain of the MOS transistor, and the second connection end of each switch module is a source of the MOS transistor.
The rectification switch tube module comprises: and a second MOS transistor, such as transistor Q3. And the control end of the rectifier switch tube module is the grid electrode of the second MOS tube. The first connecting end of the rectifier switch tube module is the drain electrode of the second MOS tube. And the second connecting end of the rectifier switch tube module is a source electrode of the second MOS tube.
The follow current switch tube module comprises: and a third MOS transistor, such as the MOS transistor Q4. And the control end of the follow current switch tube module is the grid electrode of the third MOS tube. And the first connecting end of the follow current switch tube module is the drain electrode of the third MOS tube. And the second connecting end of the follow current switch tube module is a source electrode of the third MOS tube.
In the power supply topology circuit shown in fig. 3, a forward power supply circuit is composed of a high-frequency transformer T1, a rectifying switch tube such as a MOS transistor Q3, a freewheeling switch tube such as a MOS transistor Q4, a filter capacitor such as a capacitor C1, and a filter inductor having an energy storage function such as an inductor L1.
By adopting the technical scheme of the invention, the output end of the forward power supply is positively excited in the topology of the isolated switch power supply circuit, so that the loss of the output end of the forward power supply can be reduced by rectifying the rectifying tube of the output end of the forward power supply by adopting the switch tube.
According to an embodiment of the present invention, there is also provided a control method of a switching power supply apparatus corresponding to the switching power supply apparatus, as shown in fig. 4, which is a schematic flow chart of an embodiment of the method of the present invention. The control method of the switching power supply device may include: step S110 to step S130.
At step S110, a bus voltage of the PFC circuit, a PFC current of the PFC circuit, and an output voltage of the forward power supply circuit are acquired. Bus voltage of the PFC circuit, such as bus voltage VPThe PFC current of the PFC circuit is the primary PFC current I of a high-frequency transformer T1PFCThe output voltage of the forward power supply circuit is, for example, the secondary side output voltage Vo of the high-frequency transformer T1.
At step S120, a driving signal of the PFC circuit is determined according to a bus voltage of the PFC circuit, a PFC current of the PFC circuit, and an output voltage of the forward power supply circuit.
In step S130, the switching power supply device is controlled to operate according to the driving signal of the PFC circuit, so as to convert the high voltage provided by the input power supply of the PFC circuit into low voltage to supply power to the load.
In the example shown in fig. 3, the energy of the primary side of the high frequency transformer T1 is transmitted to the secondary side of the primary side of the high frequency transformer T1 through the high frequency transformer T1 by switching on and off of the switching tube, the output signal of the Main Control Unit (MCU) controls the on and off of the MOS transistor Q1, and the bus voltage V is sampledPPFC current IPFCThe duty ratio of a driving signal of a power supply switching tube such as an MOS tube Q1 is adjusted by outputting voltage Vo, the turn ratio N1/N2 of a primary side and a secondary side of a high-frequency transformer T1 is set according to the size of the output voltage Vo, the high-frequency transformer T1 converts high-voltage electricity into low-voltage electricity, the on and off of a rectification switching tube such as an MOS tube Q3 and a freewheeling switching tube such as an MOS tube Q4 are controlled by self-driving, and then the voltage transmitted to the secondary side of the high-frequency transformer T1 is supplied to each load by a filter capacitor such as a capacitor C1 and an energy storage inductor such as an inductor L1 to obtain required low-voltage direct current electricity.
Wherein, through the switching on and shutting off of self-propelled control rectification switch tube such as MOS pipe Q3, freewheel switch tube such as MOS pipe Q4, include: the energy transmitted by the transformer is that the MOS tube Q3 is switched on, the MOS tube Q4 is switched off and the MOS tube Q3 has a rectifying function in the positive half cycle of the secondary side voltage; during the negative half cycle, the MOS transistor Q4 is switched on, the MOS transistor Q3 is switched off, and the MOS transistor Q4 has a follow current function. The synchronous rectification circuit can be spontaneously switched on and off without depending on an external driving signal.
In some embodiments, in step S130, a specific process of determining the driving signal of the PFC circuit is determined according to a bus voltage of the PFC circuit, a PFC current of the PFC circuit, and an output voltage of the forward power supply circuit, as shown in the following exemplary description.
The following further describes, with reference to a schematic flow chart of an embodiment of determining the driving signal of the PFC circuit in the method of the present invention shown in fig. 5, a specific process of determining the driving signal of the PFC circuit in step S130, including: step S210 to step S240.
And step S210, regulating the voltage according to the output voltage of the forward power supply circuit and the given value of the output voltage to obtain a first voltage regulating value.
Step S220, voltage regulation is carried out according to the bus voltage of the PFC circuit and the reference value of the bus voltage, and a second voltage regulation value is obtained.
In step S230, a voltage value corresponding to the PFC current of the PFC circuit and a sum of the first voltage adjustment value and the second voltage adjustment value are divided by a divider to obtain a first voltage, such as an output voltage U1.
Step S240, comparing the first voltage with a preset carrier voltage to obtain a comparison voltage, and using the comparison voltage as the driving signal.
In the example shown in fig. 3, the control unit (MCU) is mainly based on the bus voltage V, which is the capacitor voltage of the capacitor module (e.g. capacitor C) in the PFC circuitPPrimary PFC current I of the high-frequency transformer T1PFCAnd the secondary side output voltage Vo of the high-frequency transformer T1, and a driving signal of a power switching tube such as an MOS tube Q1 is controlled; inputting the collected secondary side output voltage Vo (such as output voltage detection value Uo) of the high-frequency transformer T1 and the output given reference voltage (such as output voltage given value Uo _ ref) into a first voltage regulator, outputting the output voltage as a first voltage regulation value Uerror1, and outputting a bus voltage V of a PFC circuitPThe voltage (or the voltage Uc at the two ends of the capacitor) and the reference voltage Uc _ ref of the PFC bus voltage are input into a second voltage regulator to obtain an output second voltage regulation value Uerror 2; the output voltages of the two voltage regulators are input into an adder, the result is used as one input of a divider, the sampling voltage of a sampling resistor Rs is used as the other input of the divider, the divider obtains an output voltage U1, the output voltage U1 is compared with a carrier voltage U2 to obtain a driving signal, and the driving signal controls the on and off of a power switch tube such as an MOS tube Q1 to achieve synchronous rectification.
According to the scheme, the PFC inductor is used as the primary winding of the high-frequency transformer, so that the area of the PCB is reduced, and the cost is reduced; a rectifier diode in a forward circuit (namely a forward power supply in an isolating switch power supply circuit topology) in a related scheme is replaced by an MOS (metal oxide semiconductor) tube, so that the loss of the forward circuit is reduced, and the efficiency of the forward circuit is improved; in addition, the secondary side of the transformer adopts self-driving, can independently operate without depending on primary side topology, and keeps the stability of the output of the forward circuit by utilizing the dual-voltage control of the low-voltage output end and the PFC output end; therefore, the problems of large area of the PCB of the switching power supply and loss caused by the diode in related schemes are solved, the circuit design can be simplified, the process cost is saved, and the circuit efficiency is improved.
Since the processing and functions implemented by the method of the present embodiment substantially correspond to the embodiments, principles and examples of the switching power supply device, reference may be made to the related descriptions in the foregoing embodiments without being detailed in the description of the present embodiment.
By adopting the technical scheme of the embodiment, the output end of the forward power supply is positively excited in the topology of the isolating switch power supply circuit, the rectifier switch tube (such as an MOS tube) is adopted to replace a rectifier diode, and the follow current switch tube (such as an MOS tube) is adopted to replace a follow current diode, so that the output stability of the forward circuit can be kept, and the power supply efficiency is improved.
In summary, it is readily understood by those skilled in the art that the advantageous modes described above can be freely combined and superimposed without conflict.
The above description is only an example of the present invention, and is not intended to limit the present invention, and it is obvious to those skilled in the art that various modifications and variations can be made in the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims (9)

1. A switching power supply device characterized by comprising: a PFC circuit and a forward power circuit; the forward power supply circuit is arranged at a PFC inductor of the PFC circuit; the forward power supply circuit includes: a high-frequency transformer and a rectifier switch tube module; wherein,
the primary winding of the high-frequency transformer is used as the input end of the forward power supply circuit; the dotted end of the secondary winding of the high-frequency transformer is connected to the control end of the rectifier switch tube module; the first connecting end of the rectifier switch tube module is used as the output end of the forward power circuit and can output power supply voltage to the first end of a load; and the synonym end of the secondary winding of the high-frequency transformer is connected to the second connecting end of the rectifier switch tube module.
2. The switching power supply device according to claim 1, wherein the PFC circuit comprises: a PFC inductance; and the primary winding of the high-frequency transformer is used as a PFC inductor of the PFC circuit.
3. The switching power supply device according to claim 2, wherein the PFC circuit further comprises: the power supply comprises a power supply switch tube module, a power supply diode module and a bus capacitor module; wherein,
the control end of the power switching tube module is used as the input end of a driving signal of the switching power supply device; the first connecting end of the power switch tube module is connected to the synonym end of the primary winding of the high-frequency transformer; the first connecting end of the power switch tube module is also connected to the anode of the power diode module; the second connecting end of the power switch tube module is grounded; and the cathode of the power diode module is grounded after passing through the bus capacitor module.
4. A switching power supply unit according to claim 3, characterized in that the power switching tube module comprises: a first MOS transistor; the control end of the power switch tube module is the grid electrode of the first MOS tube; the first connecting end of the power switch tube module is the drain electrode of the first MOS tube; the second connecting end of the power switch tube module is the source electrode of the first MOS tube.
5. The switching power supply device according to any one of claims 1 to 4, wherein the forward power supply circuit further includes: the follow current switch tube module and the energy storage inductor module; wherein,
the synonym end of the secondary winding of the high-frequency transformer is connected to the control end of the follow current switching tube module; the dotted end of the secondary winding of the high-frequency transformer is also connected to the first connecting end of the follow current switch tube module; the second connecting end of the follow current switching tube module is connected to the first connecting end of the rectification switching tube module;
the energy storage inductance module is arranged at the first connecting end of the follow current switch tube module and is connected with the second end of the load.
6. The switching power supply device according to claim 5, wherein the forward power supply circuit further comprises: a filtering module;
the filtering module is arranged between the first end of the load and the second end of the load.
7. The switching power supply device according to claim 5, wherein,
the rectification switch tube module comprises: a second MOS transistor; the control end of the rectifier switch tube module is the grid electrode of the second MOS tube; the first connecting end of the rectifier switch tube module is the drain electrode of the second MOS tube; the second connecting end of the rectifier switch tube module is a source electrode of the second MOS tube;
the follow current switch tube module comprises: a third MOS transistor; the control end of the follow current switch tube module is the grid electrode of the third MOS tube; the first connecting end of the follow current switch tube module is the drain electrode of the third MOS tube; and the second connecting end of the follow current switch tube module is a source electrode of the third MOS tube.
8. A control method of the switching power supply device according to any one of claims 1 to 7, comprising:
acquiring bus voltage of the PFC circuit, PFC current of the PFC circuit and output voltage of the forward power circuit;
determining a driving signal of the PFC circuit according to the bus voltage of the PFC circuit, the PFC current of the PFC circuit and the output voltage of the forward power supply circuit;
and controlling the switching power supply device to work according to the driving signal of the PFC circuit so as to convert high voltage provided by an input power supply of the PFC circuit into low voltage and supply power to the load.
9. The control method of the switching power supply device according to claim 8, wherein determining the driving signal of the PFC circuit based on the bus voltage of the PFC circuit, the PFC current of the PFC circuit, and the output voltage of the forward power supply circuit includes:
performing voltage regulation according to the output voltage of the forward power supply circuit and the given value of the output voltage to obtain a first voltage regulation value;
performing voltage regulation according to the bus voltage of the PFC circuit and a bus voltage reference value to obtain a second voltage regulation value;
obtaining a first voltage by a divider according to the sum of the first voltage regulating value and the second voltage regulating value and a voltage value corresponding to the PFC current of the PFC circuit;
and comparing the first voltage with a preset carrier voltage to obtain a comparison voltage, and taking the comparison voltage as the driving signal.
CN202111458977.4A 2021-12-01 2021-12-01 A switching power supply device and its control method Pending CN114172379A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111458977.4A CN114172379A (en) 2021-12-01 2021-12-01 A switching power supply device and its control method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111458977.4A CN114172379A (en) 2021-12-01 2021-12-01 A switching power supply device and its control method

Publications (1)

Publication Number Publication Date
CN114172379A true CN114172379A (en) 2022-03-11

Family

ID=80482327

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111458977.4A Pending CN114172379A (en) 2021-12-01 2021-12-01 A switching power supply device and its control method

Country Status (1)

Country Link
CN (1) CN114172379A (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6018469A (en) * 1997-02-05 2000-01-25 Computer Products, Inc. Low cost high efficiency power converter
CN104158402A (en) * 2014-08-27 2014-11-19 南京国睿新能电子有限公司 Novel boost switching power supply
KR20160141981A (en) * 2015-06-02 2016-12-12 숭실대학교산학협력단 Boost-forward differential power conditioner and control method thereof
CN111182689A (en) * 2020-02-22 2020-05-19 福州大学 Visible light communication modulation circuit and method based on single-stage forward LED drive circuit
CN111404391A (en) * 2020-04-24 2020-07-10 苏州锴威特半导体股份有限公司 Positive-shock active clamping driving circuit
US10862389B1 (en) * 2019-10-04 2020-12-08 Raytheon Company Multiple-output non-isolated active line filter
CN113489307A (en) * 2021-07-09 2021-10-08 珠海格力电器股份有限公司 Switching power supply and control method thereof

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6018469A (en) * 1997-02-05 2000-01-25 Computer Products, Inc. Low cost high efficiency power converter
CN104158402A (en) * 2014-08-27 2014-11-19 南京国睿新能电子有限公司 Novel boost switching power supply
KR20160141981A (en) * 2015-06-02 2016-12-12 숭실대학교산학협력단 Boost-forward differential power conditioner and control method thereof
US10862389B1 (en) * 2019-10-04 2020-12-08 Raytheon Company Multiple-output non-isolated active line filter
CN111182689A (en) * 2020-02-22 2020-05-19 福州大学 Visible light communication modulation circuit and method based on single-stage forward LED drive circuit
CN111404391A (en) * 2020-04-24 2020-07-10 苏州锴威特半导体股份有限公司 Positive-shock active clamping driving circuit
CN113489307A (en) * 2021-07-09 2021-10-08 珠海格力电器股份有限公司 Switching power supply and control method thereof

Similar Documents

Publication Publication Date Title
US11283288B2 (en) Integrated DC to DC converter UPS topology
CN114448263B (en) Converter based on asymmetric half-bridge flyback circuit and control method thereof
CN114884356A (en) Flyback converter and power supply system
CN112311220B (en) PFC control circuit and power supply control device
CN102437724B (en) AC-DC (alternating current-direct current) chip, system and high-voltage startup control circuit of system
CN113794368B (en) Control device and method of flyback switching power supply and flyback switching power supply
CN114583963B (en) Flyback converter and control method thereof
CN114123791A (en) A bridge-type high-gain and high-efficiency switched capacitor DC-DC converter
CN216146251U (en) Flyback switching power supply and control device thereof
CN114172379A (en) A switching power supply device and its control method
CN214591163U (en) Flyback converter
CN113726182A (en) Flyback switching power supply and control device and method thereof
CN212343642U (en) PFC auxiliary power supply circuit, switching power supply device and air conditioner
CN115566885A (en) Switching power supply circuit, device and electronic equipment
CN110601323B (en) Charging device and driving power supply generating circuit
JP2015012645A (en) Dc-dc converter and ac-dc converter
CN114285271A (en) A new type of new energy boost converter and its control method
CN111541371A (en) Direct current electric energy generation circuit for new energy application
CN219372285U (en) Voltage conversion circuit
CN119362902B (en) Power supply regulating circuit and method, power supply converting circuit and electronic equipment
CN220964655U (en) Power supply control system and LED all-in-one machine
CN219740026U (en) Power supply circuit and energy storage system
CN222339260U (en) Phase-shifting PFC converter
CN223109915U (en) Voltage conversion circuit and photovoltaic optimizer
CN118611427B (en) DC converter and circuit breaker

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination