Power supply

Abstract

A power supply comprises a first conversion circuit, a switching circuit, a second conversion circuit and a protection circuit. The first conversion circuit is used for converting input current into output current. The switching circuit is connected to the first conversion circuit, and the switching circuit is used for switching to transmit or not transmit the input current to the first conversion circuit. The second conversion circuit is connected to the first conversion circuit and the switching circuit and is used for converting the input current into the sampling current. The protection circuit is connected to the second conversion circuit and the switching circuit, and is used for filtering the sampling current with a plurality of mutually different filtering frequency bands to generate a plurality of filtering currents, and switching the switching circuit to a turn-off state when the power parameter associated with the plurality of filtering currents is higher than a set parameter.

Description

Technical Field

[0001] The present invention relates to a power supply. Background Art

[0002] In current analog power supplies, overcurrent protection mechanisms mostly use detection resistors in high-frequency switching paths or use current converters to detect current, and then the corresponding integrated circuit chips execute protection mechanisms according to the detected current. On this basis, in order to meet the test conditions of Intel's ATX3.0, a single-stage integrator needs to be added to the detection circuit to achieve the effect of circuit protection.

[0003] However, limited by the design of the single-stage integrator, if the low-frequency requirements are to be met, the cut-off frequency needs to be set to meet the low-frequency requirements, resulting in high-frequency signals not being properly processed; on the contrary, if the cut-off frequency is set to meet the high-frequency requirements, low-frequency signals are prone to accidentally trigger the protection mechanism. Summary of the Invention

[0004] In view of the above, the present invention provides a power supply.

[0005] A power supply according to an embodiment of the present invention includes: a first conversion circuit, a switching circuit, a second conversion circuit, and a protection circuit. The first conversion circuit is used to convert the input current into an output current. The switching circuit is connected to the first conversion circuit, and the switching circuit is used to switch to transmit or not transmit the input current to the first conversion circuit. The second conversion circuit is connected to the first conversion circuit and the switching circuit, and is used to convert the input current into a sampling current. The protection circuit is connected to the second conversion circuit and the switching circuit, and is used to filter the sampling current with a plurality of different filter frequency bands to generate a plurality of filtered currents, and when the power parameters associated with the plurality of filtered currents are higher than the set parameters, switch the switching circuit to the off state.

[0006] In summary, the power supply according to one or more embodiments of the present invention can prevent the power supply from being overloaded or even burned out, and can avoid the problem of accidentally triggering the protection mechanism through the protection mechanism of switching the switching circuit to the off state when the power parameter of the input current in any filter frequency band exceeds the set parameter as the protection point.

[0007] The above description of the present disclosure and the following description of the embodiments are used to illustrate and explain the spirit and principle of the present invention, and provide a further explanation of the claims of the present invention. Brief Description of the Drawings

[0008] Figure 1 It is a block diagram of a power supply shown according to an embodiment of the present invention.

[0009] Figure 2It is a block diagram of a power supply unit according to another embodiment of the present invention.

[0010] Figure 3 It is a block diagram of a power supply unit according to yet another embodiment of the present invention.

[0011] Figure 4 It is a circuit diagram of a filter and a voltage divider according to an embodiment of the present invention.

[0012] Figure 5 It is a circuit diagram of a second conversion circuit according to an embodiment of the present invention.

[0013] Figure 6 It is a flowchart for detecting power parameters according to an embodiment of the present invention.

[0014] Among them, the reference numerals are explained as follows:

[0015] 1, 2, 3: Power supply unit

[0016] 10, 20, 30: Switching circuit

[0017] 11, 21, 31: First conversion circuit

[0018] 12, 22, 32, 52: Second conversion circuit

[0019] 13, 23, 33: Protection circuit

[0020] 231a, 331a: First filter

[0021] 231b, 331b: Second filter

[0022] 232a, 332a: First voltage divider

[0023] 232b, 332b: Second voltage divider

[0024] 233, 333: Comparator

[0025] 234, 334: Controller

[0026] 431: Filter

[0027] 432: Voltage divider

[0028] 431a, 431b, 431c, 431h, 522e, 524, 525: Resistors

[0029] 431d, 431f, 431g, 432a, 522f, 523: Capacitors

[0030] 432b: First voltage dividing resistor

[0031] 432c: The second voltage-dividing resistor

[0032] 432e: Amplifier

[0033] 432d, 522a, 522b, 522c, 522d: Diodes

[0034] 521: Voltage converter

[0035] 521a: Primary-side winding

[0036] 521b: Secondary-side winding

[0037] 522: Full-wave rectifier

[0038] IN: Input terminal

[0039] OUT: Output terminal

[0040] T1, T2, T3, T4, T5, T6, T7, T8: Terminals

[0041] GND: Ground terminal

[0042] S1, S3, S5: Steps Detailed implementation manners

[0043] The detailed features and advantages of the present invention are described in detail in the following implementation manners. The content is sufficient for any person skilled in the relevant art to understand the technical content of the present invention and implement it accordingly. And according to the content, claims and drawings disclosed in this specification, any person skilled in the relevant art can easily understand the relevant purposes and advantages of the present invention. The following embodiments further illustrate the viewpoints of the present invention in detail, but do not limit the scope of the present invention in any way.

[0044] Please refer to Figure 1 , in which Figure 1 is a block diagram of a power supply according to an embodiment of the present invention. As Figure 1 shown, the power supply 1 includes a switching circuit 10, a first conversion circuit 11, a second conversion circuit 12 and a protection circuit 13. The switching circuit 10 is connected to the first conversion circuit 11, the second conversion circuit 12 and the protection circuit 13. The second conversion circuit 12 is connected to the first conversion circuit 11 and the protection circuit 13. And, the switching circuit 10 may have an input terminal IN for receiving an input current, and the first conversion circuit 11 may have an output terminal OUT for outputting a current.

[0045] The switching circuit 10 may include one or more switching transistors, such as full-bridge metal oxide semiconductor field effect transistors (MOSFETs). The switching circuit 10 is used for controlled switching to transmit or not transmit the input current to the first conversion circuit 11. Specifically, if the switching circuit 10 is controlled to switch to the off state, the switching circuit 10 does not receive the input current from the input terminal IN; if the switching circuit 10 is controlled to switch to the on state, the switching circuit 10 receives the input current from the input terminal IN and transmits the input current to the first conversion circuit 11.

[0046] The first conversion circuit 11 is used to convert the input current into an output current and output the output current via the output terminal OUT. The first conversion circuit 11 may include a voltage converter (transformer) and a rectifier. The primary winding of the voltage converter may be connected to the second conversion circuit 12, and the secondary winding may be connected to the rectifier. The output terminal of the rectifier may serve as the output terminal OUT. In an embodiment where the switching circuit 10 is implemented as a full-bridge circuit, one terminal of the primary winding of the voltage converter of the first conversion circuit 11 may be connected to the second conversion circuit 12, and the other terminal may be connected to the source of the first switching transistor and the drain of the second switching transistor of the full-bridge circuit. Additionally, the first conversion circuit 11 may further include two inverters and a capacitor (e.g., a resonant capacitor). The two inverters may be connected in parallel between one end of the second conversion circuit 12 and one end of the capacitor, and the other end of the capacitor may be connected to one terminal of the primary winding of the voltage converter.

[0047] The second conversion circuit 12 may include a voltage converter (transformer). The second conversion circuit 12 is used to convert the input current into a sampled current. Specifically, the primary winding of the voltage converter of the second conversion circuit 12 may be connected to the switching circuit 10, and the secondary winding may be connected to the protection circuit 13. In an embodiment where the switching circuit 10 is implemented as a full-bridge circuit, one terminal of the primary winding of the voltage converter of the second conversion circuit 12 may be connected to the source of the third switching transistor and the drain of the fourth switching transistor of the full-bridge circuit, and the other terminal may be connected to the first conversion circuit 11.

[0048] In one embodiment, the protection circuit 13 may include a controller. In another embodiment, the protection circuit 13 may further include a plurality of filters in addition to the controller, and the filters may be low-pass filters. The protection circuit 13 is configured to filter the sampled current at a plurality of different filtering frequency bands to generate a plurality of filtered currents, and switch the switch circuit 10 to an off state when the power parameters associated with these filtered currents are higher than the set parameters. In other words, the protection circuit 13 can divide the sampled current according to the filtering frequency bands to determine whether the power parameters of the filtered current for each filtering frequency band are higher than the set parameters. Additionally, after switching the switch circuit 10 to the off state, the protection circuit 13 may wait for a preset duration before switching the switch circuit 10 to the on state.

[0049] The filtering frequency bands can be the frequency bands during normal operation of the load. Taking the test conditions of Intel's ATX3.0 as an example, the filtering frequency bands can be the frequencies indicated in the ATX3.0 specification that the power supply will exhibit during operation. For example, the cut-off frequencies of the filtering frequency bands can be 5 kilohertz (kHz), 0.5 kilohertz (kHz), 50 hertz (Hz), and 5 hertz (Hz) respectively. The values and quantities of the filtering frequency bands described herein are only examples and are not limited by the present invention. Additionally, the power parameter can be the current value or voltage value of the filtered current.

[0050] By means of the protection mechanism of switching the switch circuit to the off state when the power parameter of the input current in any filtering frequency band exceeds the set parameter as the protection point, it is possible to prevent the power supply from being overloaded or even burned out, or to avoid the problem of false triggering of the protection mechanism.

[0051] Please refer to Figure 2 , in which Figure 2 is a block diagram of a power supply according to another embodiment of the present invention. Figure 2 This can be an embodiment where the protection circuit includes a plurality of filters. As Figure 2 shown, the power supply 2 includes a switch circuit 20, a first conversion circuit 21, a second conversion circuit 22, and a protection circuit 23. The switch circuit 20 is connected to the first conversion circuit 21, the second conversion circuit 22, and the protection circuit 23. The second conversion circuit 22 is connected to the first conversion circuit 21 and the protection circuit 23. And, the switch circuit 20 may have an input terminal IN for receiving the input current, and the first conversion circuit 21 may have an output terminal OUT for outputting the current. The switch circuit 20, the first conversion circuit 21, and the second conversion circuit 22 may be the same as Figure 1 the switch circuit 10, the first conversion circuit 11, and the second conversion circuit 12 of

[0052] As Figure 2As shown, the protection circuit 23 includes a first filter 231a, a second filter 231b, a first voltage divider 232a, a second voltage divider 232b, a comparator 233, and a controller 234. The comparator 233 and the controller 234 can be integrated into an integrated circuit. It should be noted first that Figure 2 the number of the shown filters and voltage dividers is only an example, and the present invention is not limited thereto.

[0053] The first filter 231a and the second filter 231b are connected in parallel with each other and are connected to the second conversion circuit 22. The first voltage divider 232a is connected to the output end of the first filter 231a, and the second voltage divider 232b is connected to the output end of the second filter 231b. The comparator 233 may include a plurality of sub-comparators, which are respectively connected to the output ends of the first voltage divider 232a and the second voltage divider 232b. The controller 234 is connected to the output end of the comparator 233.

[0054] The first filter 231a and the second filter 231b are used to filter the sampled current output by the second conversion circuit 22 to output a filtered current, and the first filter 231a and the second filter 231b respectively correspond to different filtering frequency bands. The first voltage divider 232a and the second voltage divider 232b are respectively used to divide the voltage of the filtered current output by the first filter 231a and the second filter 231b to output a divided voltage signal. The comparator 233 is used to compare the power parameter of the divided voltage signal of the first voltage divider 232a with a set parameter to generate a comparison result corresponding to the first voltage divider 232a, and is used to compare the power parameter of the divided voltage signal of the second voltage divider 232b with the set parameter to generate a comparison result corresponding to the second voltage divider 232b.

[0055] The controller 234 turns on or off the switch circuit 20 according to the comparison result of the first voltage divider 232a and the comparison result of the second voltage divider 232b. Further, the controller 234 can turn off the switch circuit 20 when any one of the comparison result corresponding to the first voltage divider 232a and the comparison result corresponding to the second voltage divider 232b indicates that the power parameter of the divided voltage signal meets the set parameter condition; or, the controller 234 can turn off the switch circuit 20 when both comparison results indicate that the power parameter of the divided voltage signal meets the set parameter condition. The above-mentioned set parameter satisfaction condition can be, for example, greater than a predetermined level or less than a predetermined level, and the present invention is not limited thereto. In some embodiments, the controller 234 can be, for example, an application-specific integrated circuit, a system-on-chip, a processor, or a microcontroller, etc., and the present invention is not limited thereto.

[0056] Please refer to Figure 3 , in whichFigure 3 It is a block diagram of a power supply according to another embodiment of the present invention. Figure 3 Another embodiment where the protection circuit includes multiple filters. For example Figure 3 As shown, the power supply 3 includes a switching circuit 30, a first conversion circuit 31, a second conversion circuit 32, and a protection circuit 33. The switching circuit 30 is connected to the first conversion circuit 31, the second conversion circuit 32, and the protection circuit 33. The second conversion circuit 32 is connected to the first conversion circuit 31 and the protection circuit 33. Also, the switching circuit 30 may have an input terminal IN for receiving an input current, and the first conversion circuit 31 may have an output terminal OUT for outputting a current. The switching circuit 30, the first conversion circuit 31, and the second conversion circuit 32 may be respectively the same as Figure 1 the switching circuit 10, the first conversion circuit 11, and the second conversion circuit 12, so details are not described here.

[0057] For example Figure 3 As shown, the protection circuit 33 includes a first filter 331a, a second filter 331b, a first voltage divider 332a, a second voltage divider 332b, a comparator 333, and a controller 334. It should be noted first that Figure 3 the number of the filters and voltage dividers shown is only an example, and the present invention is not limited thereto.

[0058] The first filter 331a and the second filter 331b are connected in series with each other, and the first filter 331a is connected to the second conversion circuit 32, and the second filter 331b is connected to the output terminal of the first filter 331a. The first voltage divider 332a is connected to the output terminal of the first filter 331a, and the second voltage divider 332b is connected to the output terminal of the second filter 331b. The comparator 333 may include multiple sub-comparators, which are respectively connected to the output terminals of the first voltage divider 332a and the second voltage divider 332b. The controller 334 is connected to the output terminal of the comparator 333.

[0059] The first filter 331a and the second filter 331b respectively correspond to filter frequency bands for filtering the sampled current, and the cut-off frequency of the filter frequency band of the first filter 331a is greater than the cut-off frequency of the filter frequency band of the second filter 331b. In other words, among the multiple filters sequentially connected from the second conversion circuit 32 to the comparator 333, the cut-off frequencies of the filters decrease in the connection order.

[0060] The first filter 331a is used to filter the sampled current output by the second conversion circuit 32 to output a filtered current, and the second filter 331b is used to filter the filtered current output by the first filter 331a to output another filtered current. The first voltage divider 332a and the second voltage divider 332b are respectively used to divide the voltage of the filtered current output by the first filter 331a and the second filter 331b to output a divided voltage signal. The comparator 333 is used to compare the electrical parameter of the divided voltage signal of the first voltage divider 332a with a set parameter to generate a comparison result corresponding to the first voltage divider 332a, and is used to compare the electrical parameter of the divided voltage signal of the second voltage divider 332b with the set parameter to generate a comparison result corresponding to the second voltage divider 332b. The controller 334 turns on or off the switch circuit 30 according to the comparison result corresponding to the first voltage divider 332a and the comparison result corresponding to the second voltage divider 332b. The manner in which the controller 334 controls the switch circuit 30 according to the comparison results corresponding to the first voltage divider 332a and the second voltage divider 332b can be the same as that of Figure 2 the controller 234, so it will not be elaborated here.

[0061] In addition, in Figure 2 and Figure 3 's embodiments, the gain of each voltage divider can be associated with the set parameter used by the comparator. Specifically, the gain of the voltage divider can increase as the cut-off frequency of the filtering frequency band of the filter increases. Therefore, the comparator can generate a comparison result according to the signal output by the voltage divider. And, according to Figure 2 and Figure 3 's protection circuit implemented using multiple filters, the cost of the power supply can be reduced.

[0062] Please refer to Figure 4 , where Figure 4 is a circuit diagram of a filter and a voltage divider shown according to an embodiment of the present invention. Figure 4 The filter 431 shown can be used as Figure 2 and Figure 3 's filters, and Figure 4 the voltage divider 432 shown can be used as Figure 2 and Figure 3 's voltage dividers. As Figure 4 shown, the filter 431 has a terminal T1, and the voltage divider 432 has a terminal T2, where the terminal T1 is used to connect to the second conversion circuit, and the terminal T2 is used to connect to the protection circuit.

[0063] The filter 431 includes: resistors 431a, 431b, 431c, and 431h; capacitors 431d, 431f, and 431g; and an amplifier 432e. One end of the resistor 431a is connected to the terminal T1, and the other end of the resistor 431a is connected to one end of the resistor 431b. The other end of the resistor 431b is connected to one end of the capacitor 431d and the positive input terminal of the amplifier 431e, and the other end of the capacitor 431d is connected to the ground terminal GND. One end of the resistor 431c is connected to the ground terminal GND, and the other end of the resistor 431c is connected to the negative input terminal of the amplifier 431e. The terminal T3 of the amplifier 431e can serve as the positive power supply terminal for receiving the power supply voltage (Vcc), and the negative power supply terminal of the amplifier 431e can be connected to the ground terminal GND. The output terminal of the amplifier 431e is connected to the voltage divider 432. One end of the resistor 431h is connected to one end of the resistor 431c and the negative input terminal of the amplifier 431e, and the other end of the resistor 431h is connected to the voltage divider 432. The capacitors 431f and 431g are connected in parallel between the node between the resistors 431a and 431b and the output terminal of the amplifier 431e.

[0064] The voltage divider 432 includes a capacitor 432a, a first voltage dividing resistor 432b, a second voltage dividing resistor 432c, and a diode 432d. The capacitor 432a and the second voltage dividing resistor 432c are connected in parallel between one end of the first voltage dividing resistor 432b and the ground terminal GND. The other end of the first voltage dividing resistor 432b is connected to the output terminal of the amplifier 431e. And, one end of the first voltage dividing resistor 432b is further connected to the anode of the diode 432d, and the cathode of the diode 432d is connected to the terminal T2.

[0065] In the voltage divider 432, the resistance values of the first voltage dividing resistor 432b and the second voltage dividing resistor 432c are related to the filtering frequency band of the filter 431 to which the voltage divider 432 is connected. As described above, the gain of the voltage divider 432 can be positively correlated with the cut-off frequency of the filtering frequency band of the filter 431, and the gain of the voltage divider 432 can be calculated according to the following formula (1):

[0066]

[0067] where Gain is the gain of the voltage divider 432, R1 is the resistance value of the second voltage dividing resistor 432c, and R2 is the resistance value of the first voltage dividing resistor 432b.

[0068] Please refer to Figure 5 , where Figure 5 is the circuit diagram of the second conversion circuit shown according to an embodiment of the present invention. Figure 5 The second conversion circuit 52 shown can serve as Figures 1 to 3 the second conversion circuit shown inFigure 5 As shown, the second conversion circuit 52 includes a voltage converter 521, a full wave rectifier 522, a capacitor 523, and two resistors 524 and 525.

[0069] The voltage converter 521 can particularly be a boost converter. The voltage converter 521 includes a primary side winding 521a and a secondary side winding 521b. The primary side winding 521a is connected to the first conversion circuit and the switch circuit, and the secondary side winding 521b is connected to the full wave rectifier 522. Specifically, the primary side winding 521a includes terminals T4 and T5, and the secondary side winding 521b includes terminals T6 and T7. Moreover, the second conversion circuit 52 further includes a terminal T8, which is connected to the protection circuit.

[0070] The terminal T4 is connected to the switch circuit, and the terminal T5 is connected to the first conversion circuit. For example, the terminal T4 can be connected between two switching transistors of the switch circuit (e.g., the source of one switching transistor and the drain of the other switching transistor), and the terminal T5 can be connected to the converter of the first conversion circuit.

[0071] The full wave rectifier 522 includes four diodes 522a to 522d, a resistor 522e, and a capacitor 522f. The cathode of the diode 522a is connected to the terminal T6, and the anode of the diode 522a is connected to one end of the capacitor 522f. The cathode of the diode 522b is connected to the cathode of the diode 522d and one end of the resistor 522e, and the anode of the diode 522b is connected to the cathode of the diode 522a. The cathode of the diode 522c is connected to the terminal T7, and the anode of the diode 522c is connected to the anode of the diode 522a. The cathode of the diode 522d is connected to the cathode of the diode 522b, and the anode of the diode 522d is connected to the terminal T7. The other end of the resistor 522e is connected to the other end of the capacitor 522f.

[0072] One end of the capacitor 523 is connected to one end of the capacitor 522f of the full wave rectifier 522, and the other end of the capacitor 523 is connected to the other end of the capacitor 522f of the full wave rectifier 522 and the resistor 522e.

[0073] The resistor 524 and the resistor 525 are connected in parallel between the ground terminal GND and the terminal T8, and one end of each of the resistor 524 and the resistor 525 connected to the ground terminal GND is further connected to one end of the capacitor 523, and the other end of each of the resistor 524 and the resistor 525 connected to the terminal T8 is further connected to the other end of the capacitor 523.

[0074] Please also refer to Figure 1 and Figure 6 , where Figure 6It is a flowchart for detecting power parameters according to an embodiment of the present invention. Figure 6 The steps of Figure 6 can be executed by the protection circuit 13, and in this embodiment, the protection circuit 13 can be implemented by one or more controllers or microcontrollers. As Figure 6 shown, detecting power parameters includes: Step S1: performing spectrum conversion on the sampled current and replicating it to obtain a plurality of first spectra; Step S3: removing the spectra corresponding to the normal frequency band in each of the plurality of first spectra to obtain a plurality of second spectra; and Step S5: performing inverse spectrum conversion on the plurality of second spectra to obtain values of a plurality of filtered currents as power parameters.

[0075] In Step S1, the protection circuit 13 performs spectrum conversion on the sampled current output by the second conversion circuit 12, and replicates the spectrum-converted signal into a plurality of first spectra, where the spectrum conversion can be a fast Fourier transform.

[0076] In Step S3, the protection circuit 13 removes the spectra corresponding to the normal frequency band in each first spectrum to obtain a second spectrum. The normal frequency band indicates the frequency band where the load operates normally. By removing the spectra corresponding to the normal frequency band, false triggering of the protection mechanism to switch the switching circuit 10 to the off state can be avoided.

[0077] In Step S5, the protection circuit 13 performs inverse spectrum conversion on each second spectrum to obtain the aforementioned filtered current, and determines whether to switch the switching circuit 10 to the off state according to the filtered current. The inverse spectrum conversion can be an inverse fast Fourier transform.

[0078] In addition, the protection circuit 13 can turn off the switching circuit 20 when the power parameter of any filtered current satisfies the set parameter condition; turn off the switching circuit 20 when the power parameters of all filtered currents satisfy the set parameter condition; or turn off the switching circuit 20 when the average value of the power parameters of all filtered currents satisfies the set parameter condition. The above set parameter satisfaction condition can be, for example, greater than a predetermined parameter, less than a predetermined parameter, or equal to a predetermined parameter, and the present invention does not limit this here.

[0079] According to Figure 6 the embodiment of Figure 6 implemented, the protection circuit can improve the accuracy of determining whether to turn off the switching circuit.

[0080] In summary, for the power supply according to one or more embodiments of the present invention, through the protection mechanism of switching the switching circuit to the off state when the power parameter of the input current in any filtered frequency band exceeds the set parameter as the protection point, the power supply can be prevented from being overloaded or even burned out, and the problem of false triggering of the protection mechanism can be avoided. And by implementing the protection circuit with a plurality of filters, the cost of the power supply can be reduced. By implementing the protection circuit with a controller capable of performing spectrum conversion, the accuracy of determining whether to turn off the switching circuit can be improved.

[0081] Although the present invention has been disclosed above in the foregoing embodiments, it is not intended to limit the present invention. Any modifications and refinements made without departing from the spirit and scope of the present invention fall within the scope of the patent protection of the present invention. For the scope of protection defined by the present invention, please refer to the appended claims.

Claims

1. A power supply, characterized in that, Comprising: A first conversion circuit for converting an input current into an output current; A switch circuit connected to the first conversion circuit, the switch circuit being used to switch to transmit or not transmit the input current to the first conversion circuit; A second conversion circuit connected to the first conversion circuit and the switch circuit for converting the input current into a sampling current; And A protection circuit connected to the second conversion circuit and the switch circuit for filtering the sampling current with a plurality of filtering frequency bands different from each other to generate a plurality of filtered currents, and when a power parameter associated with the plurality of filtered currents is higher than a set parameter, switching the switch circuit to an off state.

2. The power supply according to claim 1, characterized in that, The protection circuit comprises: A plurality of filters connected to the second conversion circuit, the plurality of filters corresponding to the plurality of filtering frequency bands respectively; A plurality of voltage dividers respectively connected to the plurality of output terminals of the plurality of filters; A comparator connected to the plurality of output terminals of the plurality of voltage dividers; And A controller connected to the output terminal of the comparator and the switch circuit.

3. The power supply according to claim 2, characterized in that, The plurality of filters are connected in series with each other.

4. The power supply according to claim 2, characterized in that, The plurality of filters are connected in parallel with each other.

5. The power supply according to claim 2, characterized in that, The gain of each of the plurality of voltage dividers is associated with the plurality of filtering frequency bands.

6. The power supply according to claim 2, characterized in that, Each of the plurality of voltage dividers includes a first voltage dividing resistor and a second voltage dividing resistor, and the resistance value of the first voltage dividing resistor and the resistance value of the second voltage dividing resistor of each of the plurality of voltage dividers are associated with the corresponding one of the plurality of filtering frequency bands.

7. The power supply according to claim 1, characterized in that, The second conversion circuit comprises: A voltage converter comprising a primary winding and a secondary winding, the primary winding being connected to the first conversion circuit and the switch circuit; A full-wave rectifier connected to the secondary winding; A capacitor connected to the full-wave rectifier; And Two resistors, one end of each of the two resistors being grounded and connected to one end of the capacitor, and the other end of each of the two resistors being connected to the protection circuit.

8. The power supply according to claim 1, characterized in that, The protection circuit comprises: A controller for performing spectrum conversion on the sampling current and replicating it to obtain a plurality of first spectra, removing the spectra corresponding to the normal frequency band in each of the plurality of first spectra to obtain a plurality of second spectra, and performing inverse spectrum conversion on the plurality of second spectra to obtain the values of the plurality of filtered currents as the power parameter.

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