Power supply device and its operation method

Abstract

The present invention provides a power supply device and an operation method thereof. The power supply device includes a power factor corrector, an auxiliary capacitor, a switching device, an auxiliary boost circuit, a controller, and a voltage conversion device. A first end of the switching device is electrically connected to an output end of the power factor corrector, and a second end thereof is electrically connected to one end of the auxiliary capacitor. An output end of the auxiliary boost circuit is electrically connected to the output end of the power factor corrector, an input end of the auxiliary boost circuit is electrically connected to an intermediate end of the switching device, and a ground end of the auxiliary boost circuit is electrically connected to the other end of the auxiliary capacitor. The controller is electrically connected to the switching device and the auxiliary boost circuit, and the voltage conversion device has an input end electrically connected to the output end of the power factor corrector.

Description

Technical Field

[0001] The present invention relates to a device and a method, and particularly to a power supply device and an operation method thereof. Background Art

[0002] In the application environment of a power supply, system data is an extremely important asset. In the case of unstable input voltage, a stable output voltage is required to maintain system operation or archiving. Therefore, when the input power suddenly cuts off during normal power supply, the requirement for the hold up time of the power supply output power is increasing day by day, ranging from 10 ms to 20 ms. The design of this hold up time will directly affect the design of the working range of the second-stage DC converter.

[0003] The current practice is to increase the output capacitance of the power factor corrector, which will lead to a decrease in power density. Or increase the working range of the post-stage input, but generally, the larger the working range, the lower the efficiency during normal operation.

[0004] In the first prior art, a boost circuit is connected in series after the power factor corrector to provide energy for the post-stage to maintain the output when the input AC voltage disappears. However, because it is in series with the circuit, it will increase losses and reduce the overall efficiency during normal operation. And when the input suddenly loses power and then recovers, because the energy of the main capacitor has dropped to an extremely low level, there will be a huge inrush current at the input end, which may cause the circuit breaker at the input end to trip, or the uninterruptible power supply (UPS) to enter protection.

[0005] In the second prior art, a three-switch buck circuit is connected in parallel after the power factor corrector. One of the switches is used to control the capacitor charging, and the other two switches form a buck circuit to provide the energy of the main capacitor to maintain the output when the input AC voltage disappears. However, the ability of the buck circuit to maintain the output voltage is limited. Summary of the Invention

[0006] The present invention provides a power supply device and an operation method thereof to improve the problems of the prior art.

[0007] In an embodiment of the present invention, the power supply device proposed by the present invention includes a power factor corrector, an auxiliary capacitor, a switching device, an auxiliary boost circuit, a controller, and a voltage conversion device. The switching device has a first terminal, a second terminal, and a middle terminal. The first terminal is electrically connected to the output terminal of the power factor corrector, and the second terminal is electrically connected to one end of the auxiliary capacitor. The output terminal of the auxiliary boost circuit is electrically connected to the output terminal of the power factor corrector, the input terminal of the auxiliary boost circuit is electrically connected to the middle terminal, and the ground terminal of the auxiliary boost circuit is electrically connected to the other end of the auxiliary capacitor. The controller is electrically connected to the switching device and the auxiliary boost circuit, and the voltage conversion device has an input terminal electrically connected to the output terminal of the power factor corrector. When the power factor corrector stops working, the controller controls the switching of the switching device and the auxiliary boost circuit, so that the power stored in the auxiliary capacitor can stabilize the voltage of the output terminal of the power factor corrector through the switching device and the auxiliary boost circuit.

[0008] In an embodiment of the present invention, an operating method of the power supply device proposed by the present invention, the power supply device includes a power factor corrector, a voltage conversion device, and an auxiliary circuit arranged in parallel with the voltage conversion device at the output terminal of the power factor corrector. The operating method includes the following steps: (A) When the power factor corrector operates, control the switching device in the auxiliary circuit to be in the first switching state, so that the output terminal of the power factor corrector charges the auxiliary capacitor in the auxiliary circuit through the switching device; (B) When the power factor corrector stops working and does not exceed a preset time, maintain the switching device in the first switching state; (C) When the power factor corrector stops working and exceeds the preset time, switch the switching device to the second switching state, so that the auxiliary capacitor stabilizes the voltage of the output terminal of the power factor corrector through the switching device and the auxiliary boost circuit in the auxiliary circuit respectively.

[0009] In summary, the technical solution of the present invention has obvious advantages and beneficial effects compared with the prior art. Due to the increasingly stringent requirements for high efficiency and high power density in the future, the technique of the present invention for improving the hold-up time can greatly improve the working efficiency, increase the power density by reducing the size of the main capacitor, the auxiliary circuit is easy to be modularized, and there are no side effects of the traditional auxiliary boost, which has great technical value.

[0010] The following will describe the above description in detail with embodiments and provide further explanations for the technical solution of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] To make the above and other objects, features, advantages and embodiments of the present invention more obvious and understandable, the description of the drawings is as follows:

[0012] Figure 1 is a block diagram of a power supply device according to an embodiment of the present invention;

[0013] Figure 2 is a circuit diagram of a power supply device according to an embodiment of the present invention; and

[0014] Figure 3 is a flowchart of an operation method of a power supply device according to an embodiment of the present invention.

[0015] To make the above and other objects, features, advantages and embodiments of the present invention more obvious and understandable, the reference numerals are explained as follows:

[0016] 100: Power supply device

[0017] 101: Output terminal

[0018] 102: Input terminal

[0019] 103: Ground terminal

[0020] 110: Power factor corrector

[0021] 111: Output terminal

[0022] 112: Ground terminal

[0023] 120: Auxiliary circuit

[0024] 121: Auxiliary boost circuit

[0025] 122: Switching device

[0026] 125: First terminal

[0027] 126: Intermediate terminal

[0028] 127: Second terminal

[0029] 130: Controller

[0030] 140: Voltage conversion device

[0031] 141: Input terminal

[0032] 142: Load

[0033] 143: Ground terminal

[0034] 150: Second inductor

[0035] 152: Voltage doubling circuit

[0036] 160: Rectifier

[0037] 162: Input power supply

[0038] 170: Optocoupler

[0039] C1: Auxiliary capacitor

[0040] C2: Main capacitor

[0041] D1: Auxiliary diode

[0042] D2: Diode

[0043] D11: First body diode

[0044] D12: Second body diode

[0045] L1: Auxiliary inductor

[0046] L2: First inductor

[0047] R: Current-limiting resistor

[0048] S1: First semiconductor switch

[0049] S2: Second semiconductor switch

[0050] S3: Auxiliary switch

[0051] S4: Switch

[0052] S5: Changeover switch

[0053] Vcc: Auxiliary power supply

[0054] Vc3: Voltage

[0055] Vc4: Voltage

[0056] 200: Operating method

[0057] S201~S203: Steps Detailed implementation manners

[0058] To make the description of the present invention more detailed and complete, reference may be made to the accompanying drawings and the following various embodiments, in which the same numbers represent the same or similar elements. On the other hand, well-known elements and steps are not described in the embodiments to avoid unnecessary limitations to the present invention.

[0059] In the embodiments and claims, the description related to "connection" may generally refer to that one element is indirectly coupled to another element through other elements, or one element is directly connected to another element without passing through other elements.

[0060] In the embodiments and claims, the description related to "source / drain" may generally refer to that one element can be used as a source or a drain according to the actual application.

[0061] In the embodiments and claims, unless otherwise specifically defined in the text for the article, "a" and "the" may generally refer to a single or plural number.

[0062] As used herein, "about", "approximately" or "substantially" are used to modify any quantity that can vary slightly, but such slight variations do not change its essence. In the embodiments, unless otherwise specified, it means that the error range of the value modified by "about", "approximately" or "substantially" is generally allowed to be within twenty percent, preferably within ten percent, and more preferably within five percent.

[0063] Figure 1 is a circuit diagram of a power supply device 100 according to an embodiment of the present invention. As Figure 1 shown, a secondary circuit 120 is added after the power factor corrector 110. The secondary circuit 120 includes a secondary boost circuit 121, a switching device 122, and a secondary capacitor C1. In terms of architecture, the first end 125 and the second end 127 of the switching device 122 can be two opposite ends, the middle end 126 of the switching device 122 can be a node between the first end 125 and the second end 127, the first end 125 of the switching device 122 is electrically connected to the output end 111 of the power factor corrector 110, one end of the secondary capacitor C1 is electrically connected to the second end 127 of the switching device 122, the output end 101 of the secondary boost circuit 121 is electrically connected to the output end 111 of the power factor corrector 110, the input end 102 of the secondary boost circuit 121 is electrically connected to the middle end 126 of the switching device 122, and the ground end 103 of the secondary boost circuit 121 is electrically connected to the other end of the secondary capacitor C1. The controller 130 is electrically connected to the power factor corrector 110, the switching device 122, and the secondary boost circuit 121. The voltage conversion device 140 (such as a DC-DC converter) is arranged in parallel with the secondary circuit 120. The input end 141 of the voltage conversion device 140 is electrically connected to the output end 111 of the power factor corrector 110. The output of the voltage conversion device 140 is electrically connected to the load 142. The ground end 112 of the power factor corrector 110, the ground end 103 of the secondary boost circuit 121, and the ground end 143 of the voltage conversion device 140 are grounded together. In practice, the controller 130 can generally refer to one, more than one, or all of the control circuits in the power supply device 100, and can also selectively cover external control circuits. Those skilled in the art can design it flexibly according to the actual application.

[0064] When the input power supply 162 is powered off, the controller can send out a disabling signal to stop the operation of the power factor corrector 110, and switch the switching device 122 through a switching switch S5 (such as: a bipolar junction transistor), and activate the auxiliary boost circuit 121, so that the power stored in the auxiliary capacitor C1 can pass through the switching device 122 and the auxiliary boost circuit 121 to stabilize the output terminal 111 of the power factor corrector 110, that is, the energy of the auxiliary capacitor C1 is fed back to the main circuit (such as: the power factor corrector 110), so that the voltage of the output terminal 111 of the power factor corrector 110 is maintained above a certain voltage level (such as: more than 95% of the voltage of the output terminal 111 when the power factor corrector 110 is operating normally), to maintain the operation of the subsequent power stage (such as: the voltage conversion device 140 and the load 142). This operation can reduce the working range of the subsequent power stage, so it can be designed at the optimal operating point.

[0065] To further elaborate on the hardware architecture of the above power supply device 100, please refer to Figure 1 、 Figure 2 , Figure 2 is a circuit diagram of a power supply device 100 according to an embodiment of the present invention. In Figure 2 the auxiliary boost circuit 121 includes an auxiliary diode D1, an auxiliary switch S3, and an auxiliary inductor L1. In terms of architecture, the cathode of the auxiliary diode D1 is electrically connected to the output terminal 101 of the auxiliary boost circuit 121 and is also electrically connected to the output terminal 111 of the power factor corrector 110. One end (such as: the drain) of the auxiliary switch S3 (such as: an N-channel enhancement-mode metal oxide semiconductor field effect transistor) is electrically connected to the anode of the auxiliary diode D1, the other end (such as: the source) of the auxiliary switch S3 is electrically connected to the ground terminal 103, and the control terminal (such as: the gate) of the auxiliary switch S3 is coupled to the controller 130. One end of the auxiliary inductor L1 is electrically connected to one end of the auxiliary switch S3, and the other end of the auxiliary inductor L1 is electrically connected to the input terminal 102 of the auxiliary boost circuit 121.

[0066] In an embodiment of the present invention, the switching device 122 may be a back-to-back device, which includes a first semiconductor switch S1 and a second semiconductor switch S2. Architecturally, one end (e.g., the drain) of the first semiconductor switch S1 (such as an N-channel enhancement-mode metal-oxide-semiconductor field-effect transistor) is electrically connected to the first end 125 and the output end 111 of the power factor corrector 110, and the other end (e.g., the source) of the first semiconductor switch S1 is electrically connected to the intermediate end 126 and the input end 102 of the auxiliary boost circuit 121. The first semiconductor switch S1 has a first body diode D11, and the cathode and anode of the first body diode D11 are electrically connected to one end and the other end of the first semiconductor switch S1, respectively. One end (e.g., the source) of the second semiconductor switch S2 (such as an N-channel enhancement-mode metal-oxide-semiconductor field-effect transistor) is electrically connected to the other end of the first semiconductor switch S1, the intermediate end 126, and the input end 102 of the auxiliary boost circuit 121. The other end (e.g., the drain) of the second semiconductor switch S2 is electrically connected to the second end 127 and one end of the auxiliary capacitor C1. The second semiconductor switch S2 has a second body diode D12, and the anode and cathode of the second body diode D12 are electrically connected to one end and the other end of the second semiconductor switch S2, respectively.

[0067] In an embodiment of the present invention, the switching device 122 further includes a current-limiting resistor R. Architecturally, the current-limiting resistor R is electrically connected between the first semiconductor switch S1 and the output end 111 of the power factor corrector 110. Alternatively, in another embodiment of the present invention, the current flow of the first semiconductor switch S1 is controlled by the controller 130, thereby omitting the current-limiting resistor R.

[0068] In an embodiment of the present invention, the power factor corrector 110 includes a main capacitor C2, a diode D2, a switch S4, and a first inductor L2. Architecturally, both ends of the main capacitor C2 are electrically connected to the output end 111 of the power factor corrector 110 and the ground end 112, and are also electrically connected to the output end 101 of the auxiliary boost circuit and the ground end 103, respectively. The cathode of the diode D2 is electrically connected to the cathode of the auxiliary diode D1. Both ends (e.g., the drain and the source) of the switch S4 (such as an N-channel enhancement-mode metal-oxide-semiconductor field-effect transistor) are electrically connected to the anode of the diode D2 and the ground end 112, respectively, and the control end (e.g., the gate) of the switch S4 is coupled to the controller 130. Both ends of the first inductor L2 are electrically connected to the anode of the diode D2 and the rectifier 160, and the rectifier 160 is electrically connected to the input power supply 162.

[0069] In an embodiment of the present invention, the power supply device 100 further includes a second inductor 150 and a voltage multiplier circuit 152. Architecturally, the second inductor 150 is inductively coupled to the first inductor L2, and the voltage multiplier circuit 152 is electrically connected to the second inductor 150.

[0070] In an embodiment of the present invention, the power supply device 100 further includes an optocoupler 170. Architecturally, the optocoupler 170 is electrically connected to the voltage doubler circuit 152, the controller 130, and the switching device 122.

[0071] In an embodiment of the present invention, the power supply device 100 further includes a switching switch S5 (e.g., a bipolar junction transistor). Architecturally, one end (e.g., the emitter) of the switching switch S5 is electrically connected to the other end (e.g., the source) of the first semiconductor switch S1, and the other end (e.g., the collector) is electrically connected to the control terminal (e.g., the gate) of the second semiconductor switch S2. The control terminal (e.g., the base) of the switching switch S5 is electrically connected to the control terminal (e.g., the gate) of the first semiconductor switch S1 and is coupled to the controller 130. Thus, the controller 130 can use only one control pin to ensure that the control signals of the first and second semiconductor switches S1 and S2 are always opposite. In other words, when the first semiconductor switch S1 is turned on, the second semiconductor switch S2 is turned off; conversely, when the first semiconductor switch S1 is turned off, the second semiconductor switch S2 is turned on. This is one embodiment of the present invention, but not limited thereto. The first semiconductor switch S1 and the second semiconductor switch S2 of the present invention can also be directly controlled by the controller 130 to provide independent control signals respectively.

[0072] Specifically, during operation, since the primary side power factor corrector 110 needs to detect AC loss to ensure that the input power supply 162 is powered off, but its detection needs to be delayed to avoid malfunction at the normal zero crossing point of the alternating current. Therefore, the operation of the power supply device 100 can be divided into three intervals: normal condition, AC loss not exceeding the preset time, and AC loss exceeding the preset time.

[0073] Under normal conditions (i.e., no AC power failure), the input power supply 162 provides alternating current, which is converted into direct current by the rectifier 160. The controller 130 can control the switch S4 to alternately turn on and off by modulating the voltage Vc4 to the control terminal of the switch S4, so that the power factor corrector 110 operates. In addition, power can be coupled to the second inductor 150 through the first inductor L2, so that the voltage doubler circuit 152 provides an auxiliary power supply Vcc to the switching device 122. The controller 130 also sends a control signal to turn on the first semiconductor switch S1 and turn off the second semiconductor switch S2 through the switching switch S5. The auxiliary switch S3 is in the off state, so that the auxiliary boost circuit 121 does not operate. The voltage at the output terminal 111 of the power factor corrector 110 charges the auxiliary capacitor C1 through the first semiconductor switch S1 and the second body diode D12. After the charging is completed, this circuit consumes almost no power, so there is no loss and the power conversion efficiency is not reduced under normal working conditions.

[0074] When the AC loss does not exceed a preset time (e.g., about 2 ms), that is, the input power supply 162 is powered off, the first semiconductor switch S1 remains conducting and the second semiconductor switch S2 remains off. The power factor corrector 110 stops working for no more than the preset time, and the auxiliary switch S3 also remains off. At this time, since the main capacitor C2 supplies power to the voltage conversion device 140, its voltage is lower than that of the auxiliary capacitor C1, making the second body diode D12 in the cut-off state.

[0075] When the AC loss exceeds the preset time, that is, the power factor corrector 110 stops working for more than the preset time, the controller 130 can send a control signal opposite to the original one to turn off the first semiconductor switch S1 and turn on the second semiconductor switch S2 through the switching switch S5, and control the auxiliary switch S3 to alternately conduct and turn off by modulating the voltage Vc3 to the control terminal of the auxiliary switch S3, so that the auxiliary boost circuit 121 operates. Since the voltage of the auxiliary capacitor C1 is higher than that of the main capacitor C2 at this time, there will be a path in the current path where the auxiliary capacitor C1 charges the main capacitor C2 through the second semiconductor switch S2 and the first body diode D11, and the other path is through the auxiliary switch S3 in the auxiliary boost circuit 121 controlled by the pulse width modulation (PWM) signal provided by the controller 130 to charge the main capacitor C2. When the voltage of the auxiliary capacitor C1 continues to drop, the duty cycle of the pulse width modulation (PWM) control signal of the auxiliary switch S3 becomes larger and larger to stabilize the voltage of the main capacitor C2, and the effect of extending the hold up time can be achieved.

[0076] Since the main capacitor C2 on the main circuit will be maintained at a high level, if the input power supply 162 suddenly loses power and then recovers, no extremely large inrush current will be generated, thus protecting all components on the line.

[0077] On the other hand, due to the increasing demand for the wattage of today's power supplies and the increasing demand for hold up time, but when shutting down, the primary side current of the subsequent isolation stage circuit (e.g., DC-DC converter) will gradually increase due to the decrease in the voltage of the main capacitor C2, even higher than the current-carrying capacity of the switch (e.g., metal oxide semiconductor field effect transistor) itself, so a semiconductor specification with a higher current-carrying capacity must be selected. The auxiliary circuit 120 architecture can clamp the input voltage of the isolation stage to a fixed voltage value when shutting down, thereby extending the working time of the subsequent power converter without having to replace components with a higher current-carrying capacity.

[0078] To further elaborate on the operation method of the above power supply device 100, please also refer to Figures 1 to 3 , Figure 3 which is a flowchart of an operation method 200 of a power supply device 100 according to an embodiment of the present invention. At Figure 1 ,Figure 2 In it, the power supply device 100 includes a power factor corrector 110, a voltage conversion device 140, and an auxiliary circuit 120 which is arranged in parallel with the voltage conversion device 140 at the output terminal 111 of the power factor corrector 110. As Figure 3 shown, the operation method 200 includes steps S201 to S203 (it should be understood that for the steps mentioned in this embodiment, except for those specifically stating their order, their order can be adjusted according to actual needs, and even can be executed simultaneously or partially simultaneously).

[0079] In step S201, when the power factor corrector 110 operates, the switching device 122 in the auxiliary circuit 120 is controlled to be in the first switching state, so that the output terminal 111 of the power factor corrector 110 charges the auxiliary capacitor C1 in the auxiliary circuit 120 through the switching device 122.

[0080] In step S202, when the power factor corrector 110 stops working and does not exceed the preset time, the switching device 122 is maintained in the first switching state. At this time, the main capacitor C2 in the power factor corrector 110 supplies power to the voltage conversion device 140 which is connected in parallel with the auxiliary circuit 120.

[0081] In step S203, when the power factor corrector 110 stops working and exceeds the preset time, the switching device 122 is switched to the second switching state, so that the auxiliary capacitor C1 stabilizes the voltage of the output terminal 111 of the power factor corrector 110 through the switching device 122 and the auxiliary boost circuit 121 in the auxiliary circuit 120 respectively.

[0082] In an embodiment of the present invention, step S201 is an operation mode under normal conditions (that is, the input power supply 162 does not lose power). When the power factor corrector 110 operates, the first switching state of the switching device 122 is to turn on the first semiconductor switch S1 and turn off the second semiconductor switch S2, and the auxiliary switch S3 is in the off state, so that the auxiliary boost circuit 121 does not operate. The voltage of the output terminal 111 of the power factor corrector 110 charges the auxiliary capacitor C1 through the first semiconductor switch S1 and the second body diode D12. In addition, through the inductive coupling of the first inductor L2 and the second inductor 150, the voltage doubling circuit 152 provides the auxiliary power supply Vcc to the switching device 122.

[0083] In an embodiment of the present invention, step S202 is an operation mode in which the loss of the input power supply 162 does not exceed a preset time. When the power factor corrector 110 stops working and does not exceed the preset time, the first semiconductor switch S1 is turned on and the second semiconductor switch S2 is turned off. The auxiliary switch S3 is in the off state. The voltage of the main capacitor C2 is lower than the voltage of the auxiliary capacitor C1, making the second body diode D12 in the cut-off state. The main capacitor C2 supplies power to the voltage conversion device 140.

[0084] In an embodiment of the present invention, step S203 is an operation mode in which the loss of the input power supply 162 exceeds a preset time. When the power factor corrector 110 stops working and exceeds the preset time, the second switching state of the switching device 122 is to turn off the first semiconductor switch S1 and turn on the second semiconductor switch S2, and control the auxiliary switch S3 to conduct and turn off alternately, so that the auxiliary boost circuit 121 operates. The auxiliary capacitor C1 also charges the main capacitor C2 through the second semiconductor switch S2 and the first body diode D11, and also charges the main capacitor through the auxiliary inductor L1 and the auxiliary diode D1.

[0085] Although the embodiments of the present invention are disclosed as above, they are not intended to limit the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to that defined by the appended claims.

Claims

1. A power supply device, comprising: A power factor corrector; An auxiliary capacitor; A switching device having a first terminal, a second terminal and an intermediate terminal, the first terminal being electrically connected to an output terminal of the power factor corrector, and the second terminal being electrically connected to one end of the auxiliary capacitor; An auxiliary boost circuit having an output terminal, an input terminal and a ground terminal, the output terminal of the auxiliary boost circuit being electrically connected to the output terminal of the power factor corrector, the input terminal of the auxiliary boost circuit being electrically connected to the intermediate terminal, and the ground terminal being electrically connected to the other end of the auxiliary capacitor; A controller electrically connected to the switching device and the auxiliary boost circuit; And A voltage conversion device having an input terminal electrically connected to the output terminal of the power factor corrector, The controller controls the switching of the switching device and the auxiliary boost circuit, so that the power stored in the auxiliary capacitor can stabilize the voltage of the output terminal of the power factor corrector through the switching device and the auxiliary boost circuit, Wherein, the switching device includes: A first semiconductor switch, one end of which is electrically connected to the first terminal and the output terminal of the power factor corrector, and the other end of which is electrically connected to the intermediate terminal and the input terminal of the auxiliary boost circuit. The first semiconductor switch has a first body diode, and a cathode and an anode of the first body diode are electrically connected to the one end and the other end of the first semiconductor switch respectively; and A second semiconductor switch, one end of which is electrically connected to the other end of the first semiconductor switch, the intermediate terminal and the input terminal of the auxiliary boost circuit, and the other end of the second semiconductor switch is electrically connected to the second terminal and the end of the auxiliary capacitor. The second semiconductor switch has a second body diode, and an anode and a cathode of the second body diode are electrically connected to the one end and the other end of the second semiconductor switch respectively.

2. The power supply device according to claim 1, wherein, The auxiliary boost circuit includes: An auxiliary diode, one cathode of which is electrically connected to the output terminal of the auxiliary boost circuit; An auxiliary switch, one end of which is electrically connected to an anode of the auxiliary diode, the other end of the auxiliary switch is electrically connected to the ground terminal of the auxiliary boost circuit, and a control terminal of the auxiliary switch is coupled to the controller; and An auxiliary inductor, one end of which is electrically connected to the anode of the auxiliary diode, and the other end of which is electrically connected to the input terminal of the auxiliary boost circuit.

3. The power supply device according to claim 2, wherein, When the power factor corrector operates, the controller turns on the first semiconductor switch and turns off the second semiconductor switch, and the auxiliary switch is in the off state.

4. The power supply device according to claim 3, wherein, The power factor corrector is electrically connected to an input power supply. After the input power supply is powered off, when the power factor corrector stops working and does not exceed a preset time, the auxiliary switch maintains the off state.

5. The power supply device according to claim 3, wherein, When the power factor corrector stops working and exceeds a preset time, the controller turns off the first semiconductor switch and turns on the second semiconductor switch, and controls the auxiliary switch to alternately turn on and off.

6. The power supply device according to claim 1, further comprising: A switching switch, one end of which is electrically connected to the other end of the first semiconductor switch, and the other end of which is electrically connected to a control end of the second semiconductor switch, and a control end of the switching switch is coupled to a control end of the first semiconductor switch and the controller.

7. The power supply device according to claim 2, wherein, The switching device further includes: A current limiting resistor electrically connected between the first semiconductor switch and the output end of the power factor corrector.

8. The power supply device according to claim 1, wherein, The power factor corrector includes: A main capacitor, both ends of which are respectively electrically connected to the output end of the auxiliary boost circuit and the ground end; A diode, a cathode of which is electrically connected to the output end of the auxiliary boost circuit; A switch, both ends of which are respectively electrically connected to an anode of the diode and the ground end, and a control end of the switch is coupled to the controller; and A first inductor, both ends of which are respectively electrically connected to the anode of the diode and a rectifier, and the rectifier is electrically connected to an input power supply.

9. The power supply device according to claim 8, further including: A second inductor inductively coupled to the first inductor; A voltage doubling circuit electrically connected to the second inductor; And An optocoupler electrically connected to the voltage doubling circuit, the controller and the switching device.

10. An operation method of a power supply device, the power supply device includes a power factor corrector, a voltage conversion device, and an auxiliary circuit connected in parallel with the voltage conversion device at an output end of the power factor corrector. The operation method includes the following steps: (A) When the power factor corrector operates, control a switching device in the auxiliary circuit to be in a first switching state, so that the output end of the power factor corrector charges an auxiliary capacitor in the auxiliary circuit through the switching device; (B) When the power factor corrector stops working and does not exceed a preset time, maintain the switching device in the first switching state; And (C) When the power factor corrector stops working and exceeds the preset time, switch the switching device to a second switching state, so that the auxiliary capacitor stabilizes the voltage of the output end of the power factor corrector through the switching device and an auxiliary boost circuit in the auxiliary circuit respectively, wherein, the auxiliary boost circuit includes an auxiliary diode, an auxiliary switch and an auxiliary inductor. A cathode of the auxiliary diode is electrically connected to the output end of the power factor corrector. One end of the auxiliary switch is electrically connected to an anode of the auxiliary diode. The other end of the auxiliary switch is electrically connected to a ground end. One end of the auxiliary inductor is electrically connected to the one end of the auxiliary switch. Wherein, the switching device includes a first semiconductor switch and a second semiconductor switch. One end of the first semiconductor switch is electrically connected to the output end of the power factor corrector, and the other end of the first semiconductor switch is electrically connected to the other end of the auxiliary inductor. One end of the second semiconductor switch is electrically connected to the other end of the first semiconductor switch, and the other end of the second semiconductor switch is electrically connected to the end of the auxiliary capacitor. The first semiconductor switch has a first body diode, and a cathode and an anode of the first body diode are respectively electrically connected to the one end and the other end of the first semiconductor switch. The second semiconductor switch has a second body diode, and an anode and a cathode of the second body diode are respectively electrically connected to the one end and the other end of the second semiconductor switch.

11. The operating method according to claim 10, wherein, Step (A) includes: When the power factor corrector operates, the first switching state of the switching device is to turn on the first semiconductor switch and turn off the second semiconductor switch, and the auxiliary switch is in the off state, so that the auxiliary boost circuit does not operate.

12. The operating method according to claim 10, wherein, Step (B) includes: When the power factor corrector stops working and does not exceed the preset time, turn on the first semiconductor switch and turn off the second semiconductor switch, and the auxiliary switch is in the off state.

13. The operating method according to claim 10, wherein, Step (C) includes: When the power factor corrector stops working and exceeds the preset time, the second switching state of the switching device is to turn off the first semiconductor switch and turn on the second semiconductor switch, and control the auxiliary switch to conduct and turn off alternately, so that the auxiliary boost circuit operates.

14. The operating method according to claim 10, wherein, The power supply device includes a second inductor inductively coupled to a first inductor in the power factor corrector. The second inductor is electrically connected to a voltage doubling circuit, and through the inductive coupling between the first inductor and the second inductor, the voltage doubling circuit provides an auxiliary power supply to the switching device.

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