flyback drive power supply
By using a multi-transformer parallel connection and voltage stabilization module design, the problems of large size and inaccurate output voltage of flyback drive power supplies were solved, achieving circuit layout optimization and improved driving effect.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANJING HENGLI INTELLIGENT TECH CO LTD
- Filing Date
- 2025-08-25
- Publication Date
- 2026-07-31
AI Technical Summary
Existing flyback drive power supplies have large individual transformers, which is particularly detrimental to circuit layout and product size optimization in the design of small-sized power modules, and also results in low output voltage accuracy and poor consistency.
Multiple transformers are connected in parallel, and a voltage regulator module is used to achieve dual positive and negative power output, reducing the size of the transformers and improving the accuracy and consistency of the output voltage.
It effectively reduces transformer size, optimizes circuit layout design, improves output voltage accuracy and consistency, and enhances the driving effect of the power supply.
Smart Images
Figure CN224583090U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of drive power supply technology, specifically to a flyback drive power supply. Background Technology
[0002] Flyback power supplies are commonly used in inverters to provide isolated power to drive circuits due to their advantages such as electrical isolation and voltage flexibility. Currently, most flyback drive power supplies in inverters use a single transformer with multiple outputs to drive the entire inverter's drive circuit, or a single transformer to drive a half-bridge drive circuit. In these forms, the single transformer is generally quite large.
[0003] Furthermore, to achieve dual positive and negative power output, most current flyback power supplies employ dual secondary windings on the output side, with corresponding rectifier and filter circuits in the subsequent stages to output positive and negative power supplies respectively. Given the dimensions of the two secondary windings themselves and the necessary electrical distance between them, this undoubtedly further increases the size of the transformer.
[0004] Therefore, the current flyback drive power supply has a large single transformer volume, especially in certain directions such as the height direction. This is not conducive to circuit layout design and product size optimization in the design of power module drive circuits that require small package size. Utility Model Content
[0005] To solve the above-mentioned technical problems, this utility model provides a flyback drive power supply, which can reduce the size of the transformer and is beneficial to circuit layout design and product size optimization.
[0006] The technical solution adopted in this utility model is as follows: A flyback drive power supply includes: multiple transformers, the primary windings of the multiple transformers being connected in parallel and connected to a preset input power supply via a first switching element; multiple voltage regulator modules, each voltage regulator module being configured in a one-to-one correspondence with the multiple transformers, the input side of each voltage regulator module being connected to the secondary winding of the corresponding transformer, and the output side of each voltage regulator module including a positive power output port and a negative power output port.
[0007] According to the flyback drive power supply of this invention, by connecting multiple transformers in parallel, the use of a single, large transformer can be avoided. By achieving dual positive and negative power output through a voltage regulator module, the size of the transformer can be further reduced compared to achieving dual positive and negative power output through dual windings. Therefore, the flyback drive power supply of this invention is beneficial for circuit layout design and product size optimization. Furthermore, the inclusion of a voltage regulator module can also solve the problems of low voltage accuracy and poor consistency when directly outputting voltage from a transformer, thereby improving the driving effect of the flyback drive power supply.
[0008] In addition, the flyback drive power supply of this utility model may also have the following additional technical features: The voltage regulator module includes a positive voltage regulator unit and a negative voltage regulator unit. The positive voltage regulator unit includes a first voltage regulator element and a transistor, and the negative voltage regulator unit includes a second voltage regulator element.
[0009] Specifically, the first voltage-regulating element is a Zener diode, and the second voltage-regulating element is a three-terminal voltage regulator. The positive voltage regulator unit further includes a first resistor. The collector of the transistor serves as the positive terminal of the input side of the voltage regulator module and is connected to one end of the secondary winding of the transformer. The emitter of the transistor serves as the positive terminal of the output side of the voltage regulator module. The base of the transistor is connected to the cathode of the Zener diode, and the anode of the Zener diode serves as the output ground terminal. One end of the first resistor is connected to the collector of the transistor, and the other end of the first resistor is connected to the cathode of the Zener diode. The positive terminal of the output side of the voltage regulator module and the output ground terminal constitute the positive power output port. The negative voltage regulator unit further includes a second resistor and a third resistor. The three-terminal voltage regulator has its cathode connected to the anode of the Zener diode. The anode of the three-terminal voltage regulator serves as the negative terminal of the input side of the voltage regulator module and is connected to the other end of the secondary winding of the transformer. It also serves as the negative terminal of the output side of the voltage regulator module. One end of the second resistor is connected to the cathode of the three-terminal voltage regulator, and the other end of the second resistor is connected to the reference terminal of the three-terminal voltage regulator. One end of the third resistor is connected to the reference terminal of the three-terminal voltage regulator, and the other end of the third resistor is connected to the anode of the three-terminal voltage regulator. The negative terminal of the output side of the voltage regulator module and the output ground terminal constitute the negative power supply output port.
[0010] Furthermore, the flyback drive power supply also includes a power management chip, wherein the drive signal output pin of the power management chip is connected to the control terminal of the first switching element to output a drive signal to the first switching element.
[0011] Furthermore, the flyback drive power supply also includes a power on / off module, which is connected to the power off pin of the power management chip to control the power management chip to start and stop the flyback drive power supply.
[0012] Furthermore, the flyback drive power supply also includes a current sampling module, which is connected to the current sampling pins of the first switching element and the power management chip respectively, to collect the current input to the primary winding of the transformer.
[0013] Furthermore, the flyback drive power supply also includes a voltage feedback module, which is connected to the voltage feedback pins of one of the transformers and the power management chip respectively, to acquire the voltage of the transformer.
[0014] The voltage feedback module includes a feedback winding disposed in a transformer. One end of the feedback winding is connected to the voltage feedback pin of the power management chip through a voltage detection circuit, and the other end of the feedback winding is grounded.
[0015] Furthermore, the flyback drive power supply further includes: a first absorption circuit connected between the first and second ends of the first switching element; and a second absorption circuit connected between the two ends of the primary winding of the transformer.
[0016] Furthermore, the flyback drive power supply also includes: a plurality of third absorption circuits, wherein the plurality of third absorption circuits are configured in a one-to-one correspondence with the plurality of transformers, and each of the third absorption circuits is connected to both ends of the rectifier element of the secondary winding of the corresponding transformer. Attached Figure Description
[0017] Figure 1 A block diagram of a flyback drive power supply according to an embodiment of this utility model; Figure 2 This is a circuit topology diagram of a flyback drive power supply according to an embodiment of the present invention. Figure 3 This is a circuit topology diagram of a voltage regulator module according to an embodiment of the present invention.
[0018] Figure label: Transformer 10, voltage regulator module 20, power management chip 30, power on / off module 40, current sampling module 50, voltage feedback module 60, input filter circuit 70, first absorption circuit 80, second absorption circuit 90, third absorption circuit 100. Positive voltage regulator unit 21, negative voltage regulator unit 22, feedback winding 61. Detailed Implementation
[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0020] like Figure 1As shown, the flyback drive power supply of this utility model embodiment includes multiple transformers 10 and multiple voltage regulator modules 20. Each transformer 10 includes a primary winding and a secondary winding. The primary windings of the multiple transformers 10 are connected in parallel and connected to a preset input power supply through a first switching element. The multiple voltage regulator modules 20 are arranged in a one-to-one correspondence with the multiple transformers 10. The input side of each voltage regulator module 20 is connected to the secondary winding of the corresponding transformer 10. The output side of each voltage regulator module 20 includes a positive power output port and a negative power output port.
[0021] According to the flyback drive power supply of this invention, by connecting multiple transformers in parallel, the use of a single, large transformer can be avoided. By achieving dual positive and negative power output through a voltage regulator module, the size of the transformer can be further reduced compared to achieving dual positive and negative power output through dual windings. Therefore, the flyback drive power supply of this invention is beneficial for circuit layout design and product size optimization. Furthermore, by incorporating a voltage regulator module, compared to directly outputting voltage from a transformer, the accuracy and consistency of the output voltage can be improved, thereby enhancing the driving effect of the flyback drive power supply.
[0022] like Figure 2 As shown, taking a flyback drive power supply including three transformers 10 as an example, the primary windings of the three transformers 10 are connected in parallel, one end is connected to the positive terminal of the preset input power supply Vi, and the other end is connected to the first terminal of the first switching element M1. The second terminal of the first switching element M1 is grounded. In the figure, the first switching element M1 is an NMOS (N-Metal-Oxide-Semiconductor) transistor as an example. The first terminal and the second terminal of the first switching element M1 are the drain and source of the NMOS transistor, respectively.
[0023] like Figure 2 As shown, the voltage regulator module 20 may include a positive voltage regulator unit 21 and a negative voltage regulator unit 22. The positive voltage regulator unit 21 includes a first voltage regulator element and a transistor, and the negative voltage regulator unit includes a second voltage regulator element. The positive voltage regulator unit 21 regulates the voltage on the input side of the voltage regulator module 20 to output a positive voltage; the negative voltage regulator unit 22 regulates the voltage on the input side of the voltage regulator module 20 to output a negative voltage. Thus, through two circuit units primarily composed of voltage regulator elements, dual positive and negative power supply outputs can be achieved. The use of transistors amplifies the current, thereby enhancing the driving capability of the flyback power supply.
[0024] In one embodiment of this utility model, the first voltage-regulating element may be a Zener diode, and the second voltage-regulating element may be a three-terminal voltage regulator.
[0025] like Figure 3As shown, the positive voltage regulator unit 21 may further include a first resistor R1. The collector of transistor Q serves as the positive terminal of the input side of the voltage regulator module 20 and is connected to one end of the secondary winding of transformer 10. The emitter of transistor Q serves as the positive terminal Vo+ of the output side of the voltage regulator module 20. The base of transistor Q is connected to the cathode of Zener diode D. The anode of Zener diode D serves as the output ground terminal GND. One end of the first resistor R1 is connected to the collector of transistor Q, and the other end of the first resistor R1 is connected to the cathode of Zener diode D. The positive terminal Vo+ of the output side of the voltage regulator module 20 and the output ground terminal GND constitute a positive power supply output port.
[0026] like Figure 3 As shown, the negative voltage regulator unit 22 may further include a second resistor R2 and a third resistor R3. The cathode of the three-terminal regulator T is connected to the anode of the Zener diode D. The anode of the three-terminal regulator T serves as the negative terminal of the input side of the voltage regulator module 20, and is connected to the other end of the secondary winding of the transformer 10. It also serves as the negative terminal Vo- of the output side of the voltage regulator module 20. One end of the second resistor R2 is connected to the cathode of the three-terminal regulator T, and the other end of the second resistor R2 is connected to the reference terminal of the three-terminal regulator T. One end of the third resistor R3 is connected to the reference terminal of the three-terminal regulator T, and the other end of the third resistor R3 is connected to the anode of the three-terminal regulator T. The negative terminal Vo- of the output side of the voltage regulator module 20 and the output ground terminal GND constitute a negative power supply output port.
[0027] like Figure 3 As shown, filter capacitors can also be installed at the positive power output port and the negative power output port respectively to achieve output filtering.
[0028] In one specific embodiment of this utility model, the three-terminal regulator T is model TL431, which can save costs compared to using an LDO (Low Dropout Regulator) for voltage regulation.
[0029] In one embodiment of this utility model, such as Figure 2 As shown, the flyback drive power supply may further include a power management chip 30. The power supply pin Vcc of the power management chip 30 is connected to the positive terminal of a preset input power supply Vi to obtain power from the preset input power supply Vi. The drive signal output pin DR of the power management chip 30 is connected to the control terminal of the first switching element M1 to output a drive signal to the first switching element M1. Taking the first switching element M1 as an NMOS transistor as an example, the control terminal of the first switching element M1 is the gate of the NMOS transistor, such as... Figure 2As shown, the drive signal output pin DR of the power management chip 30 is connected to the gate of the NMOS transistor through a drive resistor. By outputting a PWM (Pulse Width Modulation) drive signal to the first switching element M1 through the power management chip 30, the on and off states of the first switching element M1 are controlled, thereby realizing the energy storage and release of the primary windings of each transformer 10.
[0030] In one embodiment of this utility model, such as Figure 2 As shown, the flyback drive power supply may further include a power on / off module 40, which is connected to the power-off pin SD of the power management chip 30 to control the power management chip 40 to start and stop the flyback drive power supply. Specifically, the power on / off module 40 may include a first switching element M2 and a controller that controls the first switching element M2 to turn on and off. The first switching element M2 may be an NMOS transistor, with its drain connected to the power-off pin SD of the power management chip 30, its source connected to a power supply that can provide a high-level signal, and its gate receiving the power-on / off signal Son / off from the controller to control the power-off pin SD of the power management chip 30 to turn on or off the high-level signal, thereby realizing the sleep and wake-up of the power management chip 30 and the shutdown and start-up of the flyback drive power supply. When the flyback drive power supply is not required to work, controlling the power management chip 30 to sleep and shutting down the flyback drive power supply can significantly reduce energy consumption.
[0031] In one embodiment of this utility model, such as Figure 2 As shown, the flyback drive power supply may further include a current sampling module 50. The current sampling module 50 is connected to the first switching element M1 and the current sampling pin Isen of the power management chip 30, respectively, to collect the current of the primary winding of the input transformer 10. The current sampling module 50 may include a sampling resistor, one end of which is connected to the source of the NMOS transistor (first switching element M1), and the other end is grounded. The current sampling module 50 is configured to achieve overcurrent detection.
[0032] In one embodiment of this utility model, such as Figure 2 As shown, the flyback drive power supply may also include a voltage feedback module 60, which is connected to the voltage feedback pin FB of a transformer 10 and a power management chip 30, respectively, to acquire the voltage of the transformer 10. Figure 2 As shown, the voltage feedback module 60 includes a feedback winding 61, which is disposed in a transformer 10. One end of the feedback winding 61 is connected to the voltage feedback pin FB of the power management chip 30 through a voltage detection circuit 62, and the other end of the feedback winding 61 is grounded. Multiple transformers 10 can feed voltage back to the power management chip 30 from only one of their feedback windings 61, achieving voltage feedback while reducing costs.
[0033] In one specific embodiment of this utility model, the power management chip 30 may be an LM3478, or other chips with the above-mentioned functional pins.
[0034] In one embodiment of this utility model, such as Figure 2 As shown, an input filter circuit 70 can also be provided in the connection circuit between the preset input power supply Vi and the transformer 10, which can improve the stability of the preset input power supply Vi.
[0035] In one embodiment of this utility model, such as Figure 2 As shown, each transformer 10 has a rectifier and filter circuit between its secondary winding and the corresponding voltage regulator module 20. The rectifier element that performs the rectification function can be a rectifier diode, which can be placed at one end of the secondary winding of the transformer 10 with its cathode facing the positive terminal of the input side of the voltage regulator module 20. The filter function is performed by a filter capacitor.
[0036] In one embodiment of this utility model, such as Figure 2 As shown, the flyback drive power supply may further include a first absorption circuit 80 and a second absorption circuit 90. The first absorption circuit 80 is connected between the first and second terminals of the first switching element M1, and the second absorption circuit 90 is connected between the two ends of the primary winding of the transformer 10. The arrangement of the first absorption circuit 80 and the second absorption circuit 90 can effectively protect the NMOS (first switching element M1) from overvoltage breakdown.
[0037] In one embodiment of this utility model, such as Figure 2 As shown, the flyback drive power supply may also include multiple third absorption circuits 100, each corresponding to a multiple transformer 10. Each third absorption circuit 100 is connected to both ends of the rectifier element in the secondary winding of the corresponding transformer 10. The third absorption circuit 100 effectively protects the rectifier diodes (rectifier elements) from being damaged by excessive reverse voltage.
[0038] In one specific embodiment of this utility model, the first absorption circuit 80 and the third absorption circuit 100 can be RC absorption circuits, and the second absorption circuit 90 can be an RCD absorption circuit.
[0039] In one specific embodiment of this utility model, the preset input power supply Vi can have a wide output voltage range of 9~36V, which can adapt to the 12V low-voltage power supply system and 24V low-voltage power supply system commonly used in new energy vehicles and non-road machinery. The output voltage of the flyback drive power supply can also be adjusted according to the drive voltage requirements of different types of power modules of the inverter, such as IGBT (Insulated Gate Bipolar Transistor) or silicon carbide MOS (Metal-Oxide-Semiconductor), which is highly adaptable. For example, the positive terminal Vo+ and the negative terminal Vo- on the output side of the voltage regulator module 20 can be +18V and -2V respectively, that is, the positive power supply output port and the negative power supply output port can output a positive voltage of +18V and a negative voltage of -2V respectively.
[0040] In the description of this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. "A plurality of" means two or more, unless otherwise explicitly specified.
[0041] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0042] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0043] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0044] Furthermore, the functional units in the various embodiments of this utility model can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.
[0045] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. A flyback driving power supply, characterized by, include: Multiple transformers, the primary windings of the multiple transformers are connected in parallel and connected to a preset input power supply through a first switching element; Multiple voltage regulator modules are provided, and each voltage regulator module is configured to correspond one-to-one with a multiple transformer. The input side of each voltage regulator module is connected to the secondary winding of the corresponding transformer, and the output side of each voltage regulator module includes a positive power output port and a negative power output port.
2. The flyback driving power supply according to claim 1, characterized in that, The voltage regulator module includes a positive voltage regulator unit and a negative voltage regulator unit. The positive voltage regulator unit includes a first voltage regulator element and a transistor, and the negative voltage regulator unit includes a second voltage regulator element.
3. The flyback driving power supply according to claim 2, characterized in that, The first voltage regulator is a Zener diode, and the second voltage regulator is a three-terminal voltage regulator. The positive voltage regulator unit further includes a first resistor. The collector of the transistor serves as the positive terminal of the input side of the voltage regulator module and is connected to one end of the secondary winding of the transformer. The emitter of the transistor serves as the positive terminal of the output side of the voltage regulator module. The base of the transistor is connected to the cathode of the Zener diode. The anode of the Zener diode serves as the output ground terminal. One end of the first resistor is connected to the collector of the transistor, and the other end of the first resistor is connected to the cathode of the Zener diode. The positive terminal of the output side of the voltage regulator module and the output ground terminal constitute the positive power output port. The negative voltage regulator unit further includes a second resistor and a third resistor. The cathode of the three-terminal voltage regulator is connected to the anode of the Zener diode. The anode of the three-terminal voltage regulator serves as the negative terminal of the input side of the voltage regulator module, and is connected to the other end of the secondary winding of the transformer. It also serves as the negative terminal of the output side of the voltage regulator module. One end of the second resistor is connected to the cathode of the three-terminal voltage regulator, and the other end of the second resistor is connected to the reference terminal of the three-terminal voltage regulator. One end of the third resistor is connected to the reference terminal of the three-terminal voltage regulator, and the other end of the third resistor is connected to the anode of the three-terminal voltage regulator. The negative terminal of the output side of the voltage regulator module and the output ground terminal constitute the negative power supply output port.
4. The flyback driving power supply according to claim 1, characterized by Also includes: A power management chip, wherein the drive signal output pin of the power management chip is connected to the control terminal of the first switching element to output a drive signal to the first switching element.
5. The flyback driving power supply according to claim 4, characterized in that, Also includes: A power on / off module is provided, which is connected to the power off pin of the power management chip to control the power management chip to start and stop the flyback drive power supply.
6. The flyback driving power supply according to claim 4, characterized by Also includes: A current sampling module is connected to the current sampling pins of the first switching element and the power management chip respectively, so as to collect the current input to the primary winding of the transformer.
7. The flyback driving power supply according to claim 4, characterized by Also includes: A voltage feedback module is connected to the voltage feedback pins of one of the transformers and the power management chip respectively, in order to collect the voltage of the transformer.
8. The flyback driving power supply according to claim 7, characterized in that, The voltage feedback module includes a feedback winding disposed in a transformer. One end of the feedback winding is connected to the voltage feedback pin of the power management chip through a voltage detection circuit, and the other end of the feedback winding is grounded.
9. The flyback drive power supply according to claim 1, characterized in that, Also includes: A first absorption circuit is connected between the first terminal and the second terminal of the first switching element; The second absorption circuit is connected between the two ends of the primary winding of the transformer.
10. The flyback driving power supply according to claim 1, characterized by Also includes: Multiple third absorption circuits are provided, each corresponding to one of the multiple transformers, with each third absorption circuit connected to both ends of the rectifier element of the secondary winding of the corresponding transformer.