High-power flyback power supply system
By introducing a resonant capacitor and a synchronous control circuit architecture into the flyback power supply, the voltage spike problem in high-power applications is solved, efficient energy management is achieved, the application range of the flyback power supply is expanded, and the cost is reduced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- APOLLO ENERGY TECH CO LTD
- Filing Date
- 2024-10-29
- Publication Date
- 2026-05-01
AI Technical Summary
Flyback power supplies suffer from voltage spikes in high-power applications, leading to component damage and electromagnetic interference. They are also less efficient and therefore difficult to widely apply in high-power demand scenarios.
A novel circuit architecture based on a flyback power supply was designed. By combining resonant capacitors and transformers, voltage spike energy is absorbed through a resonant buffer circuit, and synchronous switching elements are used for control, achieving efficient energy storage and release.
Without sacrificing efficiency, it effectively solves the voltage spike problem, reduces circuit costs, expands the high-power application range of flyback power supplies, and improves overall efficiency.
Smart Images
Figure CN121966282A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a high-power flyback power supply system, and more particularly to a high-power flyback power supply system capable of applying flyback to high power. Background Technology
[0002] Flyback power supplies are a type of switching power supply topology widely used in electronic devices. Due to their simple structure, low cost, and electrical isolation, they occupy an important position in low to medium power applications.
[0003] The working principle of a flyback power supply is to use a transformer to store energy during the switching-on period and release the energy to the load during the switching-off period, thereby achieving voltage conversion and stable output. At the same time, the presence of the transformer also provides electrical isolation between the primary and secondary sides, enhancing circuit safety.
[0004] In consumer electronics, flyback power supplies are widely used in devices such as mobile phone chargers, laptop power supplies, and tablet chargers. These devices require a stable DC power supply, which flyback power supplies can meet. Furthermore, because they can accommodate a wide range of input voltages (e.g., 85VAC to 265VAC), they are compatible with voltage standards in different regions worldwide. In industrial control, communication equipment, and medical devices, flyback power supplies are used as isolated DC-DC converters to provide electrically isolated, low-power power to sensitive electronic components, protecting equipment from grid interference.
[0005] Flyback power supplies are also widely used in LED driver power supplies. Because LEDs require high current stability, flyback power supplies can provide constant current output, ensuring the brightness and lifespan of the LEDs. Similarly, in standby mode of televisions, audio equipment, and other devices, flyback power supplies, with their high efficiency and low power consumption, are widely used in standby power supplies and low-power applications, reducing energy consumption.
[0006] The advantages of flyback power supplies are mainly reflected in the following aspects. First, low cost is a major feature. Due to their simple circuit structure and small number of components, flyback power supplies have lower manufacturing costs and are suitable for mass production. Second, high safety is another advantage. Electrical isolation is achieved through transformers, protecting the safety of users and equipment and meeting international safety standards. Furthermore, flyback power supplies have a wide range of applications, adapting to a wide range of input voltages to meet the power grid requirements of different regions. In the low to medium power range, flyback power supplies have high efficiency, effectively reducing energy consumption. Finally, high design flexibility is also an important advantage. Designers can adjust the transformer turns ratio and control parameters to achieve different output voltages and power, meeting diverse application needs.
[0007] However, flyback power supplies also have some problems in application, the most prominent of which is voltage spikes. When a switching element switches from the on state to the off state, the leakage inductance on the primary side of the transformer causes a sharp drop in current, resulting in a high-amplitude voltage spike on the switching element. These voltage spikes may exceed the voltage withstand range of the switching element, leading to component breakdown and damage. Simultaneously, voltage spikes also generate electromagnetic interference (EMI), affecting the normal operation of the circuit and the operation of other equipment.
[0008] Currently, to address voltage spikes, it is common practice to add snubber circuits (such as RCD snubber circuits) or employ active clamping techniques. However, these measures increase circuit complexity and cost, and in high-power applications, voltage spikes are more severe and difficult to suppress effectively.
[0009] Therefore, designing a high-power flyback power supply is very difficult because voltage spikes are hard to handle. Generally, you can only add a very high power surge absorber and select a high-voltage switching transistor while sacrificing efficiency. Otherwise, it is difficult to achieve more than 300W.
[0010] In addition, as power increases, the leakage inductance energy and switching current of the transformer also increase, leading to a further increase in the amplitude of voltage spikes, which poses a threat to the reliability of switching elements and circuits.
[0011] Furthermore, flyback power supplies suffer from lower efficiency in high-power applications. Because the switching elements operate in a hard-switching state, switching losses are significant. Simultaneously, the transformer needs to store more energy, requiring a larger air gap and volume in the core, increasing design complexity and cost. Thermal management at high power is also a major challenge; the heat from the switching elements and transformer is difficult to dissipate in time, potentially leading to overheating and damage.
[0012] For the reasons mentioned above, flyback power supplies are generally not suitable for high-power applications. In high-power scenarios, designers tend to use other topologies, such as forward, half-bridge, or full-bridge power supplies. These topologies can more effectively control voltage spikes, reduce switching losses, and improve overall efficiency.
[0013] Therefore, this design proposes a novel circuit architecture based on a flyback power supply to address the problems caused by voltage spikes. This allows the flyback power supply to be used more effectively under high power demands without sacrificing efficiency. This will effectively reduce circuit manufacturing costs and make the application of flyback power supplies more widespread. Therefore, this design should be considered the best solution. Summary of the Invention
[0014] The high-power flyback power supply system of the present invention includes at least: a flyback power supply unit having at least one main transformer; an output circuit module electrically connected to the main transformer, the output circuit module having at least one filter element; a control circuit module electrically connected to the main buffer circuit module and the main transformer, the control circuit module having at least one first switching element; a flyback resonant power supply unit electrically connected to the flyback power supply unit, the flyback resonant power supply unit having at least one resonant transformer electrically connected to the output circuit module; an absorption circuit module electrically connected to the main transformer and the resonant transformer, the absorption circuit module having at least one resonant capacitor element; and a resonant buffer circuit module electrically connected to the resonant transformer and the absorption circuit module for receiving the resonant capacitor. The first circuit module releases discharge energy from the first switch element and outputs a second power supply to the resonant transformer; a switching module is electrically connected to the absorption circuit module and the second switching element, and the switching module is used to turn the second switching element on or off. When the first switching element is off, a high voltage spike energy is generated, which charges the resonant capacitor element. After the resonant capacitor element discharges, the second switching element is turned off, and the resonant transformer releases the second power supply energy to the output circuit module; a start control unit is electrically connected to the control circuit module and the switching module, and the start control unit is used to output a drive signal to the control circuit module and the switching module, which is used to enable the first switching element and the second switching element to conduct synchronously.
[0015] More specifically, the main transformer has a primary side and a secondary side. The primary side of the main transformer is electrically connected to the control circuit module, while the secondary side of the main transformer is electrically connected to the output circuit module.
[0016] More specifically, the flyback power supply unit also includes a main buffer circuit module electrically connected to the main transformer. The main buffer circuit module is used to receive an input power supply from an input terminal and output a first power energy to the main transformer.
[0017] More specifically, when the first switching element is turned on, it is used to store the first power energy output by the main buffer circuit module through the main transformer, and when the first switching element is turned off, the main transformer releases the first power energy to the output circuit module.
[0018] More specifically, the resonant transformer has a primary side and a secondary side. The primary side of the resonant transformer is electrically connected to the resonant buffer circuit module and the second switching element, while the secondary side of the resonant transformer is electrically connected to the output circuit module.
[0019] More specifically, when the second switching element is turned on, the resonant capacitor element discharges to the resonant buffer circuit module, and when the second switching element is turned off, the resonant transformer releases the second power energy to the output circuit module.
[0020] More specifically, the main transformer is also connected to an auxiliary power supply unit, which is electrically connected to the start-up control unit and is used to provide the power required for the operation of the start-up control unit.
[0021] More specifically, if the ground terminal of the flyback resonant power supply unit is connected to the high voltage terminal of the flyback power supply unit, the switching module also has an isolator, which is used to receive the drive signal and drive the second switching element to conduct; if the ground terminal of the flyback resonant power supply unit is connected to the low voltage terminal or ground terminal of the flyback power supply unit, the switching module does not need the isolator and can directly drive the second switching element to conduct through the drive signal.
[0022] The high-power flyback power supply system provided by this invention has the following advantages compared with other existing technologies: 1. This paper designs a new circuit architecture based on a flyback power supply to solve the problems caused by voltage spikes, so that the flyback power supply can be more effectively used in high power demand without sacrificing efficiency. This will effectively reduce the circuit manufacturing cost and make the application of the flyback power supply more widespread.
[0023] 2. In this design, both the first and second switching elements store energy each time the switching switch is turned on. When the first switching element is turned off, the resonant capacitor can absorb voltage surges for the first switching element. After absorbing the surge energy (high voltage spike energy) of the first switching element with each switching action, the energy is recovered and released to the loads on both sides of the main transformer.
[0024] 3. Although this case uses a single-stage flyback circuit as an example, the architecture of this system can be widely applied to any type of flyback circuit architecture. Therefore, this case is not limited to the application of single-stage flyback circuits.
[0025] 4. The circuit architecture in this case can reduce overall cost and achieve higher efficiency, which is something that traditional flyback circuits cannot achieve. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of the overall architecture of the high-power flyback power supply system of the present invention; Figure 2This is a schematic diagram showing the connection between the flyback power supply unit and the flyback resonant power supply unit in the high-power flyback power supply system of the present invention. Figure 3A This is a schematic diagram of the circuit architecture of the power filter in the high-power flyback power supply system of the present invention. Figure 3B This is a partial circuit architecture diagram of the flyback power unit of the high-power flyback power system of the present invention. Figure 3C A partial circuit architecture diagram of a flyback power unit for inventing a high-power flyback power system. Figure 3D This is a partial circuit architecture diagram of the flyback power unit of the high-power flyback power system of the present invention. Figure 3E This is a schematic diagram of the circuit architecture of the flyback resonant power supply unit of the high-power flyback power supply system of the present invention. Figure 3F This is a schematic diagram of the circuit architecture of the start-up control unit of the high-power flyback power supply system of the present invention; Figure 3G This is a schematic diagram of the circuit architecture of the auxiliary power supply unit of the high-power flyback power supply system of the present invention; Figure 4 This is a schematic diagram illustrating the implementation timing of the high-power flyback power supply system of the present invention; Figure 5A This is a schematic diagram of the circuit architecture of the power filter in the high-power flyback power supply system of the present invention. Figure 5B This is a partial circuit architecture diagram of the flyback power unit of the high-power flyback power system of the present invention. Figure 5C This is a partial circuit architecture diagram of the flyback power unit of the high-power flyback power system of the present invention. Figure 5D This is a schematic diagram of the circuit architecture of the flyback resonant power supply unit of the high-power flyback power supply system of the present invention. Figure 5E This is a schematic diagram of the circuit architecture of the auxiliary power supply unit of the high-power flyback power supply system of the present invention; Figure 6 This is a timing diagram of another embodiment of the high-power flyback power supply system of the present invention. Detailed Implementation
[0027] Other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of the preferred embodiments with reference to the accompanying drawings.
[0028] Please see Figure 1 and Figure 2The figure shows the overall architecture of the high-power flyback power supply system of the present invention and the architecture connection diagram of the flyback power supply unit and the flyback resonant power supply unit. As shown in the figure, the high-power flyback power supply system 1 is electrically connected to an input power supply terminal 2 and a load terminal 3.
[0029] The input power terminal 2 is used to input an input power source, while the load terminal 3 is any electronic product that requires power.
[0030] The high-power flyback power system 1 includes at least a power filter 11, a flyback power unit 12, a flyback resonant power unit 13, a start-up control unit 14, and an auxiliary power supply unit 15.
[0031] The power filter 11 is used to filter noise from the input power supply. The circuit architecture of the power filter 11 is as follows: Figure 3A As shown.
[0032] The flyback power supply unit 12 includes at least a main buffer circuit module 121, a main transformer 122 (T1), a control circuit module 123, and an output circuit module 124. The circuit architecture of the flyback power supply unit 12 is as follows: Figures 3B to 3D As shown.
[0033] The main buffer circuit module 121 is used to receive an input power supply from an input terminal and output a first power energy to the main transformer. The main buffer circuit module 121 has at least a resistive element, a capacitive element and a diode element.
[0034] The main transformer 122 has a primary side and a secondary side. The primary side of the main transformer 122 is electrically connected to the control circuit module 123, while the secondary side of the main transformer 122 is electrically connected to the output circuit module 124.
[0035] The control circuit module 123 is electrically connected to the main buffer circuit module 121 and the main transformer 122, and the control circuit module 123 has at least one first switching element (Q1 and Q2).
[0036] The output circuit module 124 is electrically connected to the main transformer 122, and the output circuit module 124 has at least one filter element.
[0037] When the first switching element (Q1 and Q2) is turned on, it is used to store the first power energy of the main buffer circuit module 121 through the main transformer 122, and when the first switching element is turned off, the main transformer 122 releases the first power energy to the output circuit module 124.
[0038] The flyback resonant power supply unit 13 includes an absorption circuit module 131 (D3, C81), a resonant buffer circuit module 132 (ZD10, R75, C79), a resonant transformer 133 (T5), a switching module 134, and a second switching element 135 (Q82). The circuit architecture of the flyback resonant power supply unit 13 is as follows: Figure 3E As shown.
[0039] The absorption circuit module 131 is electrically connected to the main transformer 122, and the absorption circuit module has at least one resonant capacitor element (C81).
[0040] The resonant buffer circuit module 132 is electrically connected to the resonant transformer 133 and the absorption circuit module 131 to receive the charging energy released by the resonant capacitor element (C81) and output a second power supply to the resonant transformer 133.
[0041] The resonant transformer 133 is electrically connected to the output circuit module 124. The resonant transformer 133 has a primary side and a secondary side. The primary side of the resonant transformer 133 is electrically connected to the absorption circuit module 131, the resonant buffer circuit module 132 and the second switching element 135, while the secondary side of the resonant transformer 133 is electrically connected to the output circuit module 124.
[0042] The switching module 134 is electrically connected to the absorption circuit module 131, the resonant buffer circuit module 132, and the second switching element 135 (Q82). If the ground terminal of the resonant buffer circuit module 132 is connected to the high voltage terminal (B+) of the flyback power supply unit 12, the switching module is also equipped with an isolator (U18) and an isolator power supply module (D12, C77, R137, Q35, and ZD5). The isolator is used to receive the drive signal and drive the second switching element 135 (Q82) to conduct.
[0043] Since the ground terminal of the resonant buffer circuit module 132 is connected to the high voltage terminal (B+) of the flyback power supply unit 12, the drive signal cannot directly drive the second switching element 135 (Q82) to conduct. Therefore, the second switching element 135 (Q82) must be driven indirectly through the isolator.
[0044] The start-up control unit 14 is electrically connected to the control circuit module 123 and the switch module 134. The start-up control unit 14 is used to output a drive signal (PGATE), which enables the first switch element (Q1 and Q2) and the second switch element 135 (Q82) to be turned on synchronously. The circuit architecture of the start-up control unit 14 is as follows: Figure 3F As shown.
[0045] Therefore, this case allows the use of the same controller's control signal (PWM drive) to synchronously drive two MOSFETs.
[0046] The startup control unit 14 can be a power supply circuit such as a PFC controller.
[0047] The auxiliary power supply unit 15 is electrically connected to the start control unit 14. The auxiliary power supply unit 15 is used to provide the power required for the operation of the start control unit 14. The circuit architecture of the auxiliary power supply unit 15 is as follows: Figure 3G As shown.
[0048] The circuit implementation in this case mainly operates as follows: (1) When the start control unit 14 outputs a drive signal, the first switching element (Q1 and Q2) and the second switching element 135 (Q82) will both be turned on; (2) Wherein, when the first switching element (Q1 and Q2) is turned on, the first power energy output by the main buffer circuit module 121 is stored in the main transformer 122; (3) When the second switching element 135 (Q82) is turned on, the resonant capacitor element (C81) discharges to the resonant buffer circuit module, and the resonant buffer circuit module 132 can output a second power energy to the resonant transformer 133, and the resonant transformer 133 stores the second power energy. (4) When the resonant capacitor element (C81) discharges to 0, the diodes (D6) and (D7) of the switching module 134 cause the second switching element 135 (Q82) to turn off; (5) When the second switching element 135 (Q82) is turned off, the secondary side of the resonant transformer 133 will release the second power energy to the output circuit module 124. (6) When the first switching element (Q1 and Q2) is turned off, the following situation will occur: (a) The secondary side of the main transformer 122 will release the first power energy to the output circuit module 124; (b) The first switching element (Q1 and Q2) on the primary side of the main transformer 122 generates a high voltage spike energy, which charges the resonant capacitor element (C81) and stores the high voltage spike energy through the resonant capacitor element (C81). (7) When the first switching element (Q1 and Q2) and the second switching element 135 (Q82) are turned on synchronously again, the main transformer 122 and the resonant transformer 133 store the first power energy and the second power energy respectively, and when the first switching element (Q1 and Q2) and the second switching element 135 (Q82) are turned off, the first power energy and the second power energy will be released to the output circuit module 124 respectively.
[0049] The first switching elements (Q1 and Q2) are as follows Figure 4 As shown, the definitions of different timing diagrams are as follows (the vertical axis of the timing diagram represents the signals at different circuit points, while the horizontal axis represents time): (1) Where (A) is a timing diagram representing the drive signal received by the first switching elements (Q1 and Q2).
[0050] (2) Where (B) represents the DC current at connection point X1 between the first switching elements (Q1 and Q2) and D17 (taking continuous mode as an example).
[0051] (3) Where (C) is V representing the first switching element (Q1 and Q2). DS Voltage, specifically the timing diagram of the primary voltage of main transformer 122.
[0052] (4) Where (D) is a timing diagram representing the drive signal received by the second switching element 135 (Q82).
[0053] (5) Where (E) is the charging and discharging timing diagram of the resonant capacitor element (C81).
[0054] (6) Where (F) represents the DC current at the connection point X2 between the second switching element 135 (Q82) and D8.
[0055] (7) Where (G) is V representing the second switching element 135 (Q82). DS The voltage, specifically the timing diagram of the primary voltage of the resonant transformer 133.
[0056] The timing variations of the circuit implementation in this case are as follows: Figure 4 As shown, the explanation is as follows: (1) When the driving signals of (A) and (D) are at high potential, it means that the first switching element (Q1 and Q2) and the second switching element 135 (Q82) are turned on.
[0057] (2) When the first switching element (Q1 and Q2) is turned on, the first power energy is stored in the main transformer 122.
[0058] (3) When the second switching element 135 (Q82) is turned on, (E) starts to discharge, and the resonant capacitor element (C81) releases energy to the resonant transformer 133.
[0059] (4) Due to the resonance process, the voltage of the resonant capacitor element (C81) will be released to 0V, and the second switching element 135 (Q82) will be turned off. The resonant transformer 133 will also start to release energy to the secondary side. At this time, the voltage of the resonant capacitor element (C81) will be maintained at 0V.
[0060] (5) When the drive signal of (A) is low, the first switching element (Q1 and Q2) is turned off, and the main transformer 122 also begins to release energy to the secondary side. Since the voltage of the resonant capacitor element (C81) is 0V, the voltage of the first switching element (Q1 and Q2) represented by (B) is V. DS The surge will rise, and the surge will be absorbed and stored by the resonant capacitor element (C81).
[0061] (6) When the driving signal of (A) is low, the DC current at connection point X1 will rise to the maximum. When the resonant capacitor element (C81) discharges, the current at point X2 will rise to the maximum. At the same time, it can be seen from the current waveform that the difference between the two circuit architectures is that one is applied to flyback and the other is applied to resonance. The circuit to which the first switching element (Q1 and Q2) belongs is applied to flyback mode, while the circuit to which the second switching element 135 (Q82) belongs is applied to resonance mode.
[0062] This invention also has another implementation circuit, which is used so that when the ground terminal of the resonant buffer circuit module 132 is connected to the low voltage terminal or the ground terminal of the flyback power supply unit 12, the switching module 134 does not need the isolator and the isolator power supply module, and can directly drive the second switching element to conduct through the driving signal.
[0063] Its circuit is as follows Figures 5A-5E As shown, the explanation is as follows: (1) The circuit architecture of the power supply filter 11 is as follows: Figure 5A As shown.
[0064] (2) The circuit architecture of the flyback power supply unit 12 is as follows: Figures 5B-5C As shown.
[0065] (3) The circuit architecture of the flyback resonant power supply unit 13 is as follows: Figure 5D As shown.
[0066] (4) The circuit architecture of the auxiliary power supply unit 15 is as follows: Figure 5E As shown.
[0067] Since the ground terminal of the flyback resonant power supply unit 13 is connected to the ground voltage terminal (ground terminal) of the flyback power supply unit 12, the drive signal can directly drive the second switching element 135 (Q41) to conduct, so there is no need to use the isolator and the isolator power supply module.
[0068] The circuit architecture of the start control unit 14 is consistent with... Figure 3F The same applies, so it will not be repeated. The other circuit implementation in this case mainly operates as follows: (1) When the start control unit 14 outputs a drive signal, the first switching element (Q1 and Q2) and the second switching element 135 (Q41) will both be turned on; (2) Wherein, when the first switching element (Q1 and Q2) is turned on, the first power energy output by the main buffer circuit module 121 is stored in the main transformer 122; (3) When the second switching element 135 (Q41) is turned on, the resonant capacitor element (C41) discharges to the resonant buffer circuit module, and the resonant buffer circuit module 132 can output a second power energy to the resonant transformer 133, and the resonant transformer 133 stores the second power energy. (4) When the resonant capacitor element (C41) discharges to 0V~B+ (the discharge can set a reference point, which is between 0 and B+), the diode (ZD3) of the switching module 134 causes the second switching element 135 (Q41) to turn off. (5) When the second switching element 135 (Q41) is turned off, the secondary side of the resonant transformer 133 will release the second power energy to the output circuit module 124. (6) When the first switching element (Q1 and Q2) is turned off, the following situation will occur: (c) The secondary side of the main transformer 122 will release the first power energy to the output circuit module 124; (d) The first switching element (Q1 and Q2) on the primary side of the main transformer 122 generates a high-voltage spike energy, which charges the resonant capacitor element (C41) and stores the high-voltage spike energy through the resonant capacitor element (C41). (The energy charging the resonant capacitor element is excluding the reflected voltage (V) of the first switching element (Q1 and Q2). ref Since the reflected voltage is applied between the drain and source of the switching transistor, it can also be called V. DS In addition to B+, due to the presence of the bridge circuit, it also includes B+. (7) When the first switching element (Q1 and Q2) and the second switching element 135 (Q41) are turned on synchronously again, the main transformer 122 and the resonant transformer 133 store the first power energy and the second power energy respectively, and when the first switching element (Q1 and Q2) and the second switching element 135 (Q41) are turned off, the first power energy and the second power energy will be released to the output circuit module 124 respectively.
[0069] The first switching elements (Q1 and Q2) are shown in Figure 6. The definitions of different timing diagrams are as follows (the vertical axis of the timing diagram represents the signal at different circuit points, while the horizontal axis of the timing diagram represents time): (1) Where (A) is a timing diagram representing the drive signal received by the first switching elements (Q1 and Q2).
[0070] (2) Where (B) is the DC current at the connection point between the first switching element (Q1 and Q2) and D3 (taking continuous mode as an example).
[0071] (3) Where (C) is V representing the first switching element (Q1 and Q2). DS Voltage, specifically the timing diagram of the primary voltage of main transformer 122.
[0072] (4) Where (D) is a timing diagram representing the drive signal received by the second switching element 135 (Q41).
[0073] (5) Where (E) is the charging and discharging timing diagram of the resonant capacitor element (C41), and the level after discharge is 0 to B+.
[0074] (6) Where (F) represents the DC current at the connection point between the second switching element 135 (Q41) and D42.
[0075] (7) Where (G) is V representing the second switching element 135 (Q41). DS The voltage, specifically the timing diagram of the primary voltage of the resonant transformer 133.
[0076] The timing variations of the circuit implementation in this case are as follows: Figure 6 As shown, the explanation is as follows: (1) When the driving signals of (A) and (D) are at high potential, it means that the first switching element (Q1 and Q2) and the second switching element 135 (Q41) are turned on.
[0077] (2) When the first switching element (Q1 and Q2) is turned on, the first power energy is stored in the main transformer 122.
[0078] (3) When the second switching element 135 (Q41) is turned on, (E) begins to discharge, and the resonant capacitor element (C41) releases energy to the resonant transformer 133.
[0079] (4) Due to the resonance process, the voltage of the resonant capacitor element (C41) will be released to 0V~B+, and the second switching element 135 (Q41) will be turned off. The resonant transformer 133 will also start to release energy to the secondary side.
[0080] (5) When the drive signal of (A) is low, the first switching element (Q1 and Q2) is turned off, and the main transformer 122 also begins to release energy to the secondary side. The V of the first switching element (Q1 and Q2) represented by (B) is... DS The surge will rise and be absorbed and stored by the resonant capacitor element (C41). Therefore, the voltage of the resonant capacitor element (C41) is ((0V~B+)+reflected voltage).
[0081] (6) When the driving signal of (A) is low, the DC current at the connection point between the first switching element (Q1 and Q2) and A5 will rise to the highest level, and the resonant capacitor element (C41) will discharge. The current at the connection point between the second switching element 135 (Q41) and D42 will rise to the highest level. At the same time, it can be seen from the current waveform that the difference between the two circuit architectures is that one is used for flyback, while the other is used for resonance. The circuit to which the first switching element (Q1 and Q2) belongs is used for flyback mode, while the circuit to which the second switching element 135 (Q82) belongs is used for resonance mode.
[0082] The high-power flyback power supply system provided by this invention has the following advantages compared with other existing technologies: 1. This paper designs a new circuit architecture based on a flyback power supply to solve the problems caused by voltage spikes, so that the flyback power supply can be more effectively used in high power demand without sacrificing efficiency. This will effectively reduce the circuit manufacturing cost and make the application of the flyback power supply more widespread.
[0083] 2. In this design, both the first and second switching elements store energy each time the switching switch is turned on. When the first switching element is turned off, the resonant capacitor can absorb voltage surges for the first switching element. After absorbing the surge energy (high voltage spike energy) of the first switching element with each switching action, the energy is recovered and released to the loads on both sides of the main transformer.
[0084] 3. Although this case uses a single-stage flyback circuit as an example, the architecture of this system can be widely applied to any type of flyback circuit architecture. Therefore, this case is not limited to the application of single-stage flyback circuits.
[0085] 4. The circuit architecture in this case can reduce overall cost and achieve higher efficiency, which is something that traditional flyback circuits cannot achieve.
[0086] The present invention has been disclosed above through the above embodiments, but it is not intended to limit the present invention. Any person skilled in the art who understands the foregoing technical features and embodiments of the present invention may make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of patent protection of the present invention shall be determined by the claims appended to this specification.
Claims
1. A high-power flyback power supply system, characterized in that, At least including: A flyback power supply unit has at least the following characteristics: One main transformer; An output circuit module is electrically connected to the main transformer, and the output circuit module has at least one filter element; A control circuit module is electrically connected to the main transformer, and the control circuit module has at least one first switching element; A flyback resonant power supply unit is electrically connected to the flyback power supply unit, and the flyback resonant power supply unit has at least the following characteristics: A resonant transformer is electrically connected to the output circuit module; An absorption circuit module is electrically connected to the main transformer and the resonant transformer, and the absorption circuit module has at least one resonant capacitor element; A resonant buffer circuit module is electrically connected to the resonant transformer and the absorption circuit module to receive the discharge energy released by the resonant capacitor element and output a second power supply to the resonant transformer. A second switching element is electrically connected to the resonant buffer circuit module and the resonant transformer; A switching module is electrically connected to the absorption circuit module and the second switching element. The switching module is used to turn the second switching element on or off. When the first switching element is off, a high voltage spike energy is generated. The high voltage spike energy charges the resonant capacitor element. After the resonant capacitor element discharges, the second switching element is turned off. The resonant transformer releases the second power energy to the output circuit module. A start control unit is electrically connected to the control circuit module and the switch module. The start control unit is used to output a drive signal to the control circuit module and the switch module. The drive signal is used to enable the first switch element and the second switch element to be turned on synchronously.
2. The high-power flyback power supply system as described in claim 1, characterized in that, The main transformer has a primary side and a secondary side. The primary side of the main transformer is electrically connected to the control circuit module, while the secondary side of the main transformer is electrically connected to the output circuit module.
3. The high-power flyback power supply system as described in claim 1, characterized in that, The flyback power supply unit also includes a main buffer circuit module electrically connected to the main transformer. The main buffer circuit module is used to receive the input power from an input terminal and output a first power energy to the main transformer.
4. The high-power flyback power supply system as described in claim 3, characterized in that, When the first switching element is turned on, it is used to store the first power energy output by the main buffer circuit module through the main transformer, and when the first switching element is turned off, the main transformer releases the first power energy to the output circuit module.
5. The high-power flyback power supply system as described in claim 1, characterized in that, The resonant transformer has a primary side and a secondary side. The primary side of the resonant transformer is electrically connected to the resonant buffer circuit module and the second switching element, while the secondary side of the resonant transformer is electrically connected to the output circuit module.
6. The high-power flyback power supply system as described in claim 1, characterized in that, When the second switching element is turned on, the resonant capacitor element discharges to the resonant buffer circuit module, and when the second switching element is turned off, the resonant transformer releases the second power energy to the output circuit module.
7. The high-power flyback power supply system as described in claim 1, characterized in that, The main transformer is also connected to an auxiliary power supply unit, which is electrically connected to the start-up control unit and is used to provide the power required for the operation of the start-up control unit.
8. The high-power flyback power supply system as described in claim 1, characterized in that, If the ground terminal of the flyback resonant power supply unit is connected to the high voltage terminal of the flyback power supply unit, the switching module also has an isolator, which is used to receive the drive signal and drive the second switching element to conduct. If the ground terminal of the flyback resonant power supply unit is connected to the low voltage terminal or ground terminal of the flyback power supply unit, the switching module does not need the isolator and can directly drive the second switching element to conduct through the drive signal.