A multi-channel adaptive input auxiliary switching power supply

Abstract

This invention discloses a multi-channel adaptive input auxiliary switching power supply, belonging to the field of switching power supply technology. The switching power supply includes a multi-primary transformer with N primary windings and one secondary winding. Each input voltage source is connected to its corresponding primary winding and outputs a voltage signal through a shared secondary winding. Each group of input voltage sources is connected to a power management module. The MOSFET drive signal output by the power management module is connected to the gate of a high-voltage MOSFET via a high-voltage MOSFET drive module. A voltage stress absorption module is installed between the drain of the high-voltage MOSFET and the primary winding to suppress voltage stress caused by simultaneous AC and DC voltage inputs. The output terminal of the transformer secondary winding is connected to an output rectifier and filter module. Each power management module is also connected to the output terminal through an independent feedback module. This invention's auxiliary switching power supply features a compact structure, flexible input, and high efficiency, effectively reducing auxiliary power supply costs and space requirements.

Description

Technical Field

[0001] This utility model relates to the field of switching power supply technology, and in particular to an auxiliary switching power supply with multiple adaptive inputs. Background Technology

[0002] In recent years, with the rapid development of China's new energy industry, the industry has placed higher demands on the technical performance of new energy equipment, especially in terms of system stability, operating efficiency, control flexibility, and cost control. To meet the startup requirements under different operating conditions and to avoid the paralysis of the entire system due to a single point of failure, the control systems of new energy power plants, such as photovoltaic power plants, wind farms, and energy storage systems, typically need to be able to obtain power from multiple energy sources.

[0003] Common power sources include main power sources (such as photovoltaic arrays), power grids, batteries, and diesel generators. To achieve stable power supply from these multiple energy inputs, existing technologies often employ multiple auxiliary switching power supplies connected to different energy nodes to ensure reliable operation of the control system under various operating conditions.

[0004] However, configuring multiple independent auxiliary switching power supplies in a new energy system also brings a series of problems and challenges: First, hardware costs increase significantly. Since each auxiliary switching power supply requires a complete power conversion circuit and related electronic components, the use of multiple auxiliary switching power supplies directly leads to an increase in overall material costs.

[0005] Secondly, the system's operating efficiency decreases. In most operating conditions, only one set of auxiliary switching power supplies is actually working, while the rest are in standby or redundant states. This not only increases the number of energy conversion stages but also reduces the overall efficiency of the system.

[0006] Finally, multiple auxiliary switching power supplies occupy a large PCB space, increasing the complexity of the internal layout design of the equipment, which is not conducive to the miniaturization and integration of the equipment and limits the application adaptability of the product in compact space environments.

[0007] In summary, there is an urgent need to propose a multi-channel adaptive input auxiliary switching power supply design that is structurally sound, cost-effective, efficient, and space-efficient, in order to effectively address the technical bottlenecks caused by multiple auxiliary switching power supplies in new energy systems and improve the overall performance and market competitiveness of new energy equipment. Utility Model Content

[0008] The technical problem to be solved by this utility model is to provide a multi-channel adaptive input auxiliary switching power supply that addresses the above-mentioned deficiencies of the prior art, effectively reduces costs, ensures operational stability, improves the efficiency of the auxiliary switching power supply, saves internal space, and meets the design requirements of current new energy auxiliary switching power supplies.

[0009] To achieve the above objectives, this utility model provides a multi-channel adaptive input auxiliary switching power supply, which includes a multi-primary-side transformer and N sets of input voltage sources;

[0010] The multi-primary transformer has N primary windings and one secondary winding; the N input voltage sources are respectively connected to the corresponding primary windings, and each primary winding outputs a voltage signal through the secondary winding.

[0011] Each input voltage source is connected to a power management module. The power input terminal of the power management module is connected to the corresponding input voltage source. The MOSFET drive signal output by the power management module is connected to the gate of the high-voltage MOSFET through the MOSFET drive module. The drain of the high-voltage MOSFET is connected to the primary winding through the voltage stress absorption module. The voltage stress absorption module is used to reduce the voltage stress caused by the simultaneous input of AC and DC voltage sources to a single transformer.

[0012] The output terminal of the secondary winding is connected to the output rectifier and filter module, which is used to rectify and filter the output voltage of the transformer secondary winding.

[0013] Each power management module is connected to the output of the rectifier and filter module via an independent feedback module.

[0014] In the multi-channel adaptive input auxiliary switching power supply of this utility model, the power management module includes a power management chip, a zero-crossing detection circuit connected to the zero-crossing detection pin of the power management chip, and a soft-start circuit connected to the VCC power supply pin of the power management chip. The soft-start circuit is connected to the input voltage source.

[0015] In the multi-channel adaptive input auxiliary switching power supply of this utility model, the multi-primary transformer further includes N auxiliary windings, the N primary windings having the same winding direction; the winding direction of the auxiliary windings and the secondary windings is opposite to that of the primary windings; the auxiliary windings are connected to the zero-crossing detection pin of the power management chip through the zero-crossing detection circuit, and are also connected to the VCC power supply pin of the power management chip through the soft-start circuit.

[0016] In the multi-channel adaptive input auxiliary switching power supply of this utility model, the voltage stress absorption module includes a decoupling diode, the anode of the decoupling diode is connected to the primary winding, and the cathode of the decoupling diode is connected to the drain of the high-voltage MOSFET.

[0017] In the multi-channel adaptive input auxiliary switching power supply of this invention, the feedback module includes a three-terminal regulator and an optocoupler.

[0018] In the multi-channel adaptive input auxiliary switching power supply of this invention, the MOS transistor driving module includes a push-pull circuit.

[0019] In the multi-channel adaptive input auxiliary switching power supply of this utility model, the output rectification and filtering module includes a rectifier diode, an output filter capacitor, and a load resistor.

[0020] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0021] 1. Significantly reduced system cost: By integrating multiple auxiliary switching power supplies into a single circuit structure, multiple transformers and their corresponding output rectifiers, filters, and dummy load resistors are eliminated. Compared with the traditional discrete auxiliary power supply structure, the number of components used in this invention is significantly reduced, thereby effectively reducing material and manufacturing costs.

[0022] 2. Effectively reduces device size and optimizes spatial layout: This utility model adopts a transformer structure with multiple inputs sharing a single side winding, allowing multiple auxiliary power sources that were originally scattered to be integrated onto the same circuit board, significantly reducing the overall size of the auxiliary power source module. This not only saves internal space but also provides more possibilities for the rational arrangement of other key components, which is conducive to realizing the miniaturization and compact design of new energy equipment.

[0023] 3. Improve overall system efficiency: By eliminating multiple rectifier and filter components on the secondary side of the transformer, the corresponding conduction losses and static power consumption are reduced. At the same time, redundant losses generated by multiple auxiliary power sources operating in parallel are avoided, thereby significantly improving the working efficiency and energy conversion rate of the auxiliary switching power supply. Attached Figure Description

[0024] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0025] Figure 1 This is a structural block diagram of the flyback power supply of this utility model.

[0026] Figure 2This is a circuit diagram of the main power topology according to an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of the power management chip and its peripheral circuit according to an embodiment of the present invention.

[0028] Figure 4 This is a schematic diagram of the high-voltage MOS transistor driving circuit according to an embodiment of the present invention.

[0029] Figure 5 This is a simulation diagram of the DC MOSFET voltage stress during power-on without adding a decoupling diode.

[0030] Figure 6 This is a simulation diagram of the DC MOSFET voltage stress during power-on when a decoupling diode is added.

[0031] Figure 7 This is the circuit schematic of the main power topology of multiple auxiliary switching power supplies. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0033] The general idea of ​​this utility model is to simultaneously input multiple sets of input power into multiple primary-side transformers, adopt a single secondary-side output, and use a voltage stress absorption module to solve the voltage stress problem caused by simultaneous AC and DC input into a single transformer.

[0034] The embodiments of this utility model will now be described in further detail with reference to the accompanying drawings. It should be understood that the embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.

[0035] This utility model embodiment provides a multi-channel adaptive input auxiliary switching power supply, the auxiliary switching power supply including a multi-primary-side transformer and N sets of input voltage sources;

[0036] The multi-primary transformer has N primary windings and one secondary winding; the N input voltage sources are respectively connected to the corresponding primary windings, and each primary winding outputs a voltage signal through the secondary winding.

[0037] Each input voltage source is connected to a power management module. The power input terminal of the power management module is connected to the corresponding input voltage source. The MOSFET drive signal output by the power management module is connected to the gate of the high-voltage MOSFET through the MOSFET drive module. The drain of the high-voltage MOSFET is connected to the primary winding through the voltage stress absorption module. The voltage stress absorption module is used to reduce the voltage stress caused by the simultaneous input of AC and DC voltage sources to a single transformer.

[0038] The output terminal of the secondary winding is connected to the output rectifier and filter module, which is used to rectify and filter the output voltage of the transformer secondary winding.

[0039] Each power management module is connected to the output of the rectifier and filter module via an independent feedback module.

[0040] In this embodiment of the invention, different input voltage sources are connected to different primary windings of multiple primary transformers, and share a single secondary winding for output. The voltage stress absorption module reduces the voltage stress caused by simultaneous input of AC and DC voltage sources to a single transformer. Compared with the scheme where each input voltage source is connected to an independent transformer, this reduces the number of transformers and rectifier / filter modules, effectively reducing the size of the auxiliary switching power supply. This saves internal space, provides more space for the arrangement of other components, reduces losses from secondary components, and thus improves the overall efficiency of the auxiliary switching power supply.

[0041] In this embodiment of the present invention, the power management module includes a power management chip, a zero-crossing detection circuit connected to the zero-crossing detection pin of the power management chip, and a soft-start circuit connected to the VCC power supply pin of the power management chip. The soft-start circuit is connected to the input voltage source.

[0042] The power management chip can also incorporate overvoltage detection circuits, overcurrent detection circuits, and low-power timing capacitors.

[0043] In this embodiment of the present invention, the multi-primary transformer further includes N auxiliary windings, the N primary windings having the same winding direction; the winding directions of the auxiliary windings and secondary windings are opposite to those of the primary windings; the auxiliary windings are connected to the zero-crossing detection pin of the power management chip through the zero-crossing detection circuit, and are also connected to the VCC power supply pin of the power management chip through the soft-start circuit.

[0044] The power management chip uses the zero-crossing point of the auxiliary winding voltage to determine the resonance start time, and then infers the valley position of the Vds resonant voltage of the high-voltage MOSFET, achieving valley-based low-loss turn-on. The voltages of multiple primary windings cross zero at the same time, thus controlling multiple high-voltage MOSFETs to turn on simultaneously. The input voltage source charges the capacitor in the soft-start circuit, enabling the power management chip to reach its startup voltage and enter normal operating mode. Subsequently, the auxiliary winding maintains the operating level of the VCC power pin of the power management chip.

[0045] In this embodiment of the invention, the voltage stress absorption module includes a decoupling diode. The anode of the decoupling diode is connected to the primary winding, and the cathode of the decoupling diode is connected to the drain of the high-voltage MOSFET. The decoupling diode is used to isolate reverse-current circuits from different primary windings, ensuring the flyback power supply operates normally under different conditions, while effectively reducing the extreme stress experienced by the MOSFET under certain conditions.

[0046] In this embodiment of the invention, the feedback module includes a three-terminal voltage regulator and an optocoupler. The feedback module in this embodiment is a type-three compensator based on the AZ431, and also includes capacitors, resistors, and other components. The feedback module is used to compensate for zeros and poles in the control loop of the switching power supply, ensuring that the switching power supply has sufficient amplitude and phase margins to meet the dynamic and static performance requirements of the flyback switching power supply. The input voltage is reflected in the numerator of the power stage transfer function of the switching power supply; that is, the input voltage is positively correlated with the DC gain of the switching power supply (only for buck topologies). The larger the input voltage, the larger the DC gain. Because the position of the open-loop gain crossover frequency needs to be reasonably controlled, assuming that different input voltages in the system share the same feedback loop (i.e., the same parameter design), the open-loop gain crossover frequency of the feedback loop corresponding to a certain input voltage may be changed to a position that would cause system instability. Therefore, the feedback module corresponding to different input voltage sources needs to have different capacitor and resistor parameter designs, so that optimal loop compensation parameters can be determined according to different input voltage ranges, ensuring that the auxiliary switching power supply has a good dynamic response.

[0047] In this embodiment of the invention, the MOSFET driving module includes a push-pull circuit. The push-pull structure enhances the driving capability of the power management chip, increases the driving voltage, and allows the MOSFET to operate at a lower on-resistance position, thus reducing conduction losses.

[0048] In this embodiment of the invention, the output rectifier and filter module includes a rectifier diode, an output filter capacitor, and a load resistor. The main function of the output filter module is to stabilize the output voltage.

[0049] Example

[0050] This embodiment describes a dual-input adaptive auxiliary switching power supply suitable for energy storage inverters. Since the energy storage inverter needs to draw power from both the grid and battery sides, it is designed with two inputs: a DC input from the battery and an AC input from the grid. The structural framework of this auxiliary switching power supply is as follows: Figure 1 As shown, the specific circuit is as follows: Figures 2 to 4 As shown. Figure 2 This is the circuit schematic of the main power topology in this embodiment. Figure 3 This is a schematic diagram of the power management chip and its peripheral circuit according to an embodiment of the present invention. Figure 4 This is a schematic diagram of a high-voltage MOSFET drive circuit.

[0051] like Figure 1 As shown, both the AC and DC inputs are connected to the primary input terminals of the multi-primary transformer. The output terminals of the multi-primary transformer are connected to the output rectifier and filter module. The AC input is connected to the multi-primary transformer via the power management module, the MOSFET driver module, the high-voltage MOSFET, and the voltage stress absorption module. The two power management modules are connected to the two feedback modules respectively.

[0052] like Figure 2 As shown, the main power topology circuit schematic includes a multi-primary-side transformer TX1. The multi-primary-side transformer TX1 comprises an AC input primary winding P1, an AC auxiliary winding S2, a DC input primary winding P2, a DC auxiliary winding S3, and a secondary winding S1. The AC input primary winding P1 and the DC input primary winding P2 have the same winding direction, while the secondary windings S1, S2, and S3 have the same winding direction but opposite to those of the AC input primary windings P1 and P2. One end of the AC input primary winding P1 and the DC input primary winding P2 are connected to the AC and DC inputs, respectively, and the other end is connected to the voltage stress absorption module. The secondary winding S1 is connected to the output rectifier and filter module. The AC auxiliary windings S2 and S3 are connected to the power management chip and its peripheral circuits, respectively. In addition to the function of a transformer in a conventional flyback switching power supply, the multi-primary-side transformer couples the AC and DC input energy and outputs it through the same secondary winding.

[0053] Continue to refer to Figure 2The high-voltage MOSFET corresponding to the AC input is the second MOSFET Q2, and the high-voltage MOSFET corresponding to the DC input is the first MOSFET Q1. The voltage stress absorption module includes a voltage absorption module for the AC input-side MOSFET composed of a first resistor R1, a first capacitor C1, a first diode D1, and a third diode D3, and a voltage absorption module for the DC input-side MOSFET composed of a fourth resistor R4, a second diode D2, a second capacitor C2, and a fourth diode D4. The principle of a conventional RCD absorption module is that when the MOSFET is turned off, the primary winding of the transformer stores energy. Since the current cannot change abruptly, leakage inductance will generate a high-voltage spike. The capacitor provides a low-impedance path to limit the current rise, and the resistor dissipates the energy, effectively suppressing the voltage spike. In this embodiment, the transformer has two different inputs controlled by different MOSFETs. During the power supply startup phase, there may be a phase difference between the turn-on and turn-off of the two MOSFETs, leading to more severe voltage stress on the MOSFETs.

[0054] The voltage stress absorption module described in this embodiment is based on the commonly used RCD absorption module, and a decoupling diode is added between the MOSFET and the primary winding of the transformer for decoupling between different primary windings. Figure 2 The third diode (D3) and the fourth diode (D4) in the decoupling diode are connected to the primary winding with their positive terminals and to the drain of the high-voltage MOSFET with their negative terminals, which can effectively reduce the voltage stress on the MOSFET.

[0055] The following is based on Figure 2 Let's take an example to illustrate the necessity of adding decoupling diodes. Assuming both primary windings have the same number of turns, when both MOSFETs Q1 and Q2 are off, diodes D1 and D2 are cut off, while D3 and D4 are on. At this point, the voltage across the two high-voltage MOSFETs can be considered the input voltage of the two windings. When both high-voltage MOSFETs are on simultaneously, due to Lenz's law, the winding with the higher input voltage will generate a magnetic field, and the winding with the lower input voltage will induce a back electromotive force (EMF). This ultimately causes the energy input to the high-voltage input winding to "reverse flow" into the low-voltage input winding. When one high-voltage MOSFET is off and the other is on, if the input voltage on the side with the high-voltage MOSFET on is higher than that on the side with the high-voltage MOSFET off, a back EMF equal to the higher input voltage will be induced in the winding with the high-voltage MOSFET off. Since the input voltage is less than the induced back EMF, the high-voltage power supply will ultimately charge the low-voltage power supply. Since the simultaneous turn-on of two high-voltage MOSFETs or the turn-on of one MOSFET and the turn-off of the other can cause the high input voltage to flow back to the low input voltage, a decoupling diode must be added between the primary winding and the high-voltage MOSFET to cut off the backflow circuit.

[0056] In this embodiment of the invention, the voltage stress with and without a decoupling diode was verified through simulation. Without the decoupling diode, with an AC input of 300V and a DC input of 800V, the high-voltage MOSFET on the DC side experiences significant voltage stress during the startup of the auxiliary switching power supply. Figure 5 As shown. After adding the decoupling diode, the voltage stress experienced by the DC-side MOSFET during startup is significantly reduced, such as... Figure 6 As shown. Figure 5 and Figure 6 The middle section compares the voltage stress borne by the high-voltage transistors under normal power supply operation, including cases where both high-voltage MOSFETs are conducting, one is conducting, and both are turned off. Figure 5 In medium and high voltage MOSFETs, the maximum voltage stress they withstand reaches over 2.4kV, but in Figure 6 The voltage has dropped to around 1.7kV. Furthermore, compared to... Figure 5 , 6 The minimum voltage that the high-voltage MOSFET can withstand after the medium power supply is operating stably. Figure 6 The voltage stress on the MOSFET in the circuit is 0V, while Figure 5 The voltage is 500V, which is because the diode bears the reverse voltage stress after the decoupling diode is added.

[0057] like Figure 2 As shown, in this embodiment, the feedback module includes an AC feedback module and a DC feedback module. The AC and DC feedback modules have the same circuit structure, both consisting of optocouplers (U1, U2), TL431 (U3, U5), and capacitor-resistor devices. They are type-three compensators based on the TL431, which are commonly used in flyback circuit design. To ensure good dynamic response of the power supply, the feedback loops on the AC and DC sides have different parameter designs depending on the range of the input voltage. In specific implementations, the TL431 can also be replaced with an AZ431.

[0058] In this embodiment, the output rectifier and filter module consists of a fifth diode D5, a fourth capacitor C4, a fifth capacitor C5, and a seventh resistor R7. The fifth diode D5 is a necessary design element for the flyback power supply filter. The fourth capacitor C4 and the fifth capacitor C5 serve to filter and stabilize the voltage. The dummy load R7 is used to stabilize the output voltage. The flyback power supply has current source characteristics and cannot operate in an open circuit.

[0059] like Figure 3 As shown, in this embodiment, the power management chip is NCP1380D. Figure 3This is the circuit diagram of the power management chip and its peripheral circuits on the AC side. The design of the DC side is the same as that of the AC side. One end of the 27th resistor R27 is connected to the Aux1 terminal of the transformer auxiliary winding S2, and the other end is connected to the positive terminal of the 18th diode D18 and the 28th resistor R28. The 18th diode D18 and the 28th resistor R28 are connected in parallel and then connected in series with the parallel combination of the 13th capacitor C13 and the 29th resistor R29 to form a zero-crossing detection circuit. The power management chip uses the zero-crossing point of the voltage of the auxiliary winding to determine the time of resonance start, and then infers the valley position of the Vds resonant voltage of the high-voltage MOSFET to achieve valley capture and low-loss turn-on.

[0060] The sixth diode D6, the seventh diode D7, the sixteenth resistor R16, the thirteenth resistor R13, and the ninth capacitor C9 and the tenth capacitor C10 constitute the soft-start circuit of the power management chip. The anode of the sixth diode D6 is connected to the Aux1 terminal of the transformer auxiliary winding S2, and one end of the thirteenth resistor R13 is connected to the AC voltage source input. Before the power management chip starts up, it first charges the ninth capacitor C9 through the thirteenth resistor R13. When the capacitor rises to the startup voltage of the power management chip, the chip starts emitting a waveform. Subsequently, the auxiliary winding is charged through Aux1 to maintain the operating level of the VCC pin of the power management chip.

[0061] In this embodiment, the AC and DC auxiliary windings are coupled to a multi-primary transformer. The voltages of the two primary windings cross zero at the same time, thereby controlling the first MOSFET Q1 and the second MOSFET Q2 to turn on at the same time. The feedback pin FB of the power management chip U4 is connected to the feedback module; the current detection pin CS is connected to the source of the second MOSFET Q2 via the third resistor R3, and overcurrent protection is achieved through this pin; the fault detection pin Fault is connected to the midpoint of the series connection of the thirtieth resistor R30 and the thirty-first resistor R31, and the other end of the thirtieth resistor R30 is connected to the input voltage and current. The input voltage is detected through this circuit to achieve overvoltage protection; the timing pin Ct is connected to the fourteenth capacitor C14, and the switching frequency of the flyback power supply under low power consumption is set through this pin; the power supply pin VCC is connected to the power soft-start module; and the drive pin DRV is connected to the MOSFET drive module.

[0062] In this embodiment, as Figure 4 As shown, the MOSFET driver module consists of the ninth transistor Q9, the thirteenth transistor Q10, the thirty-second resistor R32, the thirty-third resistor R33, and the fifteenth capacitor C15. This is a commonly used push-pull structure. Using this circuit can increase the driving voltage and reduce the MOSFET loss.

[0063] Figure 7 To and Figure 2The corresponding multi-transformer auxiliary switching power supply circuit schematic shows that the AC input voltage source and the DC input voltage source are each connected to an independent transformer, as indicated by the red box. Figure 7 Compared to Figure 2 The extra components. Therefore, it can be seen that... Figure 2 The proposed solution significantly reduces the number of components.

[0064] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0065] 1. Significantly reduced system cost: By integrating multiple auxiliary switching power supplies into a single circuit structure, multiple transformers and their corresponding output rectifiers, filters, and dummy load resistors are eliminated. Compared with the traditional discrete auxiliary power supply structure, the number of components used in this invention is significantly reduced, thereby effectively reducing material and manufacturing costs.

[0066] 2. Effectively reduces device size and optimizes spatial layout: This utility model adopts a transformer structure with multiple inputs sharing a single side winding, allowing multiple auxiliary power sources that were originally scattered to be integrated onto the same circuit board, significantly reducing the overall size of the auxiliary power source module. This not only saves internal space but also provides more possibilities for the rational arrangement of other key components, which is conducive to realizing the miniaturization and compact design of new energy equipment.

[0067] 3. Improve overall system efficiency: By eliminating multiple rectifier and filter components on the secondary side of the transformer, the corresponding conduction losses and static power consumption are reduced. At the same time, redundant losses generated by multiple auxiliary power sources operating in parallel are avoided, thereby significantly improving the working efficiency and energy conversion rate of the auxiliary switching power supply.

[0068] In summary, this utility model provides a multi-channel adaptive input auxiliary switching power supply solution with reasonable structure and superior performance, which solves the key technical problems of high cost, low efficiency and large size of auxiliary power supplies in the prior art, and has good application prospects and promotion value.

[0069] The above are merely specific embodiments of this utility model and should not be construed as limiting the scope of this utility model. Equivalent variations made by those skilled in the art based on this invention, as well as changes known to those skilled in the art, should still fall within the scope of this utility model.

Claims

1. A multi-channel adaptive input auxiliary switching power supply, characterized in that, The auxiliary switching power supply includes a multi-primary-side transformer and N sets of input voltage sources; The multi-primary transformer has N primary windings and one secondary winding; the N input voltage sources are respectively connected to the corresponding primary windings, and each primary winding outputs a voltage signal through the secondary winding. Each input voltage source is connected to a power management module. The power input terminal of the power management module is connected to the corresponding input voltage source. The MOSFET drive signal output by the power management module is connected to the gate of the high-voltage MOSFET through the MOSFET drive module. The drain of the high-voltage MOSFET is connected to the primary winding through the voltage stress absorption module. The voltage stress absorption module is used to reduce the voltage stress caused by the simultaneous input of AC and DC voltage sources to a single transformer. The output terminal of the secondary winding is connected to the output rectifier and filter module, which is used to rectify and filter the output voltage of the transformer secondary winding. Each power management module is connected to the output of the rectifier and filter module via an independent feedback module.

2. The multi-channel adaptive input auxiliary switching power supply according to claim 1, characterized in that, The power management module includes a power management chip, a zero-crossing detection circuit connected to the zero-crossing detection pin of the power management chip, and a soft-start circuit connected to the VCC power supply pin of the power management chip. The soft-start circuit is connected to the input voltage source.

3. The multi-channel adaptive input auxiliary switching power supply according to claim 2, characterized in that, The multi-primary transformer also includes N auxiliary windings, the N primary windings having the same winding direction; the winding direction of the auxiliary windings and secondary windings is opposite to that of the primary windings; the auxiliary windings are connected to the zero-crossing detection pin of the power management chip through the zero-crossing detection circuit, and are also connected to the VCC power supply pin of the power management chip through the soft-start circuit.

4. The multi-channel adaptive input auxiliary switching power supply according to claim 1, characterized in that, The voltage stress absorption module includes a decoupling diode, the anode of which is connected to the primary winding, and the cathode of which is connected to the drain of the high-voltage MOS transistor.

5. The multi-channel adaptive input auxiliary switching power supply according to claim 1, characterized in that, The feedback module includes a three-terminal voltage regulator and an optocoupler.

6. The auxiliary switching power supply with multiple adaptive inputs according to claim 1, characterized in that, The MOS transistor drive module includes a push-pull circuit.

7. The multi-channel adaptive input auxiliary switching power supply according to claim 1, characterized in that, The output rectifier and filter module includes a rectifier diode, an output filter capacitor, and a load resistor.

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