TWI880526B - Power supply - Google Patents

Abstract

A power supply includes: a first converting circuit, a switch circuit, a second converting circuit and a protecting circuit. The first converting circuit is configured to convert an input current into an output current. The switch circuit is connected to the first converting circuit. The switch circuit is configured to switch to transmit or not transmit the input current to the first converting circuit. The second converting circuit is connected to the first converting circuit and the switch circuit. The second converting circuit is configured to convert the input current into a sample current. The protecting circuit is connected to the second converting circuit and the switch circuit. The protecting circuit is configured to filter on the sample current with different filter frequency bands to generate a plurality of filtered currents, and switch the switch circuit into a turned-off state when an electric parameter associated with the filtered currents is higher than a set parameter.

Description

Power supply

The present invention relates to a power supply.

In current analog power supplies, overcurrent protection mechanisms are mostly implemented by using detection resistors in high-frequency switching paths, or using current transformers to detect current, and then the corresponding integrated circuit chip executes the protection mechanism based on the detected current. On this basis, in order to meet Intel's ATX3.0 test conditions, a single-stage integrator needs to be added to the detection circuit to achieve the circuit protection effect.

However, due to the limitation of the single-stage integrator design, if low-frequency requirements are to be met, the cutoff frequency must be set to meet low-frequency requirements, resulting in the inability to properly process high-frequency signals; on the contrary, if the cutoff frequency is set to meet high-frequency requirements, low-frequency signals are likely to mistakenly trigger the protection mechanism.

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

A power supply according to an embodiment of the present invention includes: a first conversion circuit, a switch circuit, a second conversion circuit and a protection circuit. The first conversion circuit is used to convert an input current into an output current. The switch circuit is connected to the first conversion circuit, and the switch 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 switch 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 switch circuit, and is used to filter the sampling current with multiple filter frequency bands different from each other to generate multiple filter currents, and when the power parameters associated with the multiple filter currents are higher than the set parameters, the switch circuit is switched to the off state.

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 avoid the problem of false triggering of the protection mechanism by switching the switch 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.

The above description of the disclosed content and the following description of the implementation method are used to demonstrate and explain the spirit and principle of the present invention, and provide a further explanation of the scope of the patent application of the present invention.

1,2,3: Power supply

10,20,30: Switching circuit

11,21,31: First conversion circuit

12,22,32,52: Second conversion circuit

13,23,33: Protection circuit

231a,331a: First filter

231b,331b: Second filter

232a,332a: first voltage divider

232b,332b: Second voltage divider

233,333: Comparator

234,334:Controller

431:Filter

432: Voltage divider

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

431d,431f,431g,432a,522f,523:Capacitor

432b: First voltage divider resistor

432c: Second voltage divider resistor

431e:Amplifier

432d,522a,522b,522c,522d: diode

521: Voltage converter

521a: Primary side winding set

521b: Secondary side winding set

522: Full-wave rectifier

IN: Input terminal

OUT: output port

T1,T2,T3,T4,T5,T6,T7,T8:Terminal

GND: Ground

S1, S3, S5: Steps

FIG1 is a block diagram of a power supply according to an embodiment of the present invention.

FIG2 is a block diagram of a power supply according to another embodiment of the present invention.

FIG3 is a block diagram of a power supply according to another embodiment of the present invention.

FIG4 is a circuit diagram of a filter and a voltage divider according to an embodiment of the present invention.

FIG5 is a circuit diagram of a second conversion circuit according to an embodiment of the present invention.

FIG6 is a flow chart of detecting power parameters according to an embodiment of the present invention.

The detailed features and advantages of the present invention are described in detail in the following implementation method. The content is sufficient for anyone familiar with the relevant technology to understand the technical content of the present invention and implement it accordingly. According to the content disclosed in this specification, the scope of the patent application and the drawings, anyone familiar with the relevant technology can easily understand the relevant purposes and advantages of the present invention. The following embodiments are to further illustrate the viewpoints of the present invention, but do not limit the scope of the present invention by any viewpoint.

Please refer to FIG. 1, which is a block diagram of a power supply according to an embodiment of the present invention. As shown in FIG. 1, 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. In addition, 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.

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

The first conversion circuit 11 is used to convert the input current into the output current and output the output current through 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, and the output terminal of the rectifier may serve as the output terminal OUT. In an embodiment in which 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. In addition, the first conversion circuit 11 may further include two converters and capacitors (e.g., resonant capacitors), the two converters 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 end of the primary winding of the voltage converter.

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 can be connected to the switching circuit 10, and the secondary winding can be connected to the protection circuit 13. In an embodiment in which the switching circuit 10 is implemented as a full-bridge circuit, one end of the primary winding of the voltage converter of the second conversion circuit 12 can 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 end can be connected to the first conversion circuit 11.

In one embodiment, the protection circuit 13 may include a controller. In another embodiment, the protection circuit 13 may include a plurality of filters in addition to the controller, wherein the filters may be low-pass filters. The protection circuit 13 is used to filter the sampled current with a plurality of filter frequency bands different from each other to generate a plurality of filter currents, and when the power parameters associated with the filter currents are higher than the set parameters, the switch circuit 10 is switched to the off state. In other words, the protection circuit 13 can divide the sampled current according to the filter frequency bands to determine whether the power parameter of the filter current of each filter frequency band is higher than the set parameter. In addition, after the switch circuit 10 is switched to the off state, the protection circuit 13 can wait for a preset time and then switch the switch circuit 10 to the on state.

The filter frequency band may be a frequency band when the load is operating normally. Taking Intel's ATX3.0 test conditions as an example, the filter frequency band may be a frequency indicated in the ATX3.0 specification that the power supply will appear when operating. For example, the cutoff frequencies of the filter frequency band may be 5 kilohertz (KHz), 0.5 kilohertz (KHz), 50 Hz, and 5 Hz, respectively. The values and quantities of the filter frequency bands described herein are only examples and are not limited by the present invention. In addition, the power parameter may be a current value or a voltage value of the filter current.

When the power parameter of the input current in any filter frequency band exceeds the set parameter as the protection point, the protection mechanism switches the switch circuit to the off state, which can prevent the power supply from overloading or even burning, or avoid the problem of false triggering of the protection mechanism.

Please refer to FIG. 2, which is a block diagram of a power supply according to another embodiment of the present invention. FIG. 2 may be an embodiment in which the protection circuit includes a plurality of filters. As shown in FIG. 2, the power supply 2 includes a switching circuit 20, a first conversion circuit 21, a second conversion circuit 22, and a protection circuit 23. The switching 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. In addition, the switching circuit 20 may have an input terminal IN for receiving an input current, and the first conversion circuit 21 may have an output terminal OUT for outputting a current. The switch circuit 20, the first conversion circuit 21 and the second conversion circuit 22 may be respectively the same as the switch circuit 10, the first conversion circuit 11 and the second conversion circuit 12 of FIG. 1, and thus will not be described in detail here.

As shown in FIG2 , 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 that the number of filters and voltage dividers shown in FIG2 is only an example and is not limited by the present invention.

The first filter 231a and the second filter 231b are connected in parallel to each other and 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.

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 the filtered current, and the first filter 231a and the second filter 231b correspond to different filter frequency bands respectively. The first voltage divider 232a and the second voltage divider 232b are used to divide the voltage of the filtered current output by the first filter 231a and the second filter 231b to output the divided signal respectively. The comparator 233 is used to compare the power parameter and the setting parameter of the voltage-dividing signal of the first voltage divider 232a to generate a comparison result corresponding to the first voltage divider 232a, and is used to compare the power parameter and the setting parameter of the voltage-dividing signal of the second voltage divider 232b to generate a comparison result corresponding to the second voltage divider 232b.

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. In other words, the controller 234 may turn off the switch circuit 20 when either the comparison result corresponding to the first voltage divider 232a or the comparison result corresponding to the second voltage divider 232b indicates that the power parameter of the voltage divider signal meets the set parameter condition; or the controller 234 may turn off the switch circuit 20 when both comparison results indicate that the power parameter of the voltage divider signal meets the set parameter condition. The above-mentioned set parameter meeting the condition may be, for example, greater than a preset calibration, or less than a preset calibration, and the present invention is not limited thereto. In some embodiments, the controller 234 may be, for example, an application-specific integrated circuit, a system-on-chip, a processor, or a microcontroller, etc., but the present invention is not limited thereto.

Please refer to FIG. 3, which is a block diagram of a power supply according to another embodiment of the present invention. FIG. 3 may be another embodiment in which the protection circuit includes a plurality of filters. As shown in FIG. 3, 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. Furthermore, 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 switch circuit 30, the first conversion circuit 31 and the second conversion circuit 32 may be respectively the same as the switch circuit 10, the first conversion circuit 11 and the second conversion circuit 12 of FIG. 1, and thus will not be described in detail here.

As shown in FIG3 , 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 that the number of filters and voltage dividers shown in FIG3 is only an example and is not limited by the present invention.

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 end of the first filter 331a. The first voltage divider 332a is connected to the output end of the first filter 331a, and the second voltage divider 332b is connected to the output end of the second filter 331b. The comparator 333 may include a plurality of sub-comparators, which are respectively connected to the output ends of the first voltage divider 332a and the second voltage divider 332b. The controller 334 is connected to the output end of the comparator 333.

The first filter 331a and the second filter 331b respectively correspond to the filter bands for filtering the sampled current, and the cutoff frequency of the filter band of the first filter 331a is greater than the cutoff frequency of the filter 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 cutoff frequency of the filter decreases in the order of connection.

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 used to divide the voltage of the filtered current output by the first filter 331a and the second filter 331b to output a divided signal. The comparator 333 is used to compare the power parameter of the voltage-dividing signal of the first voltage divider 332a with the setting parameter to generate a comparison result corresponding to the first voltage divider 332a, and to compare the power parameter of the voltage-dividing signal of the second voltage divider 332b with the setting 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 controller 334 controls the switch circuit 30 according to the comparison results of the first voltage divider 332a and the second voltage divider 332b in the same manner as the controller 234 in FIG. 2, so it will not be described in detail here.

In addition, in the embodiments of FIG. 2 and FIG. 3, the gain of each voltage divider can be related to the setting parameters used by the comparator. Specifically, the gain of the voltage divider can increase as the cutoff frequency of the filter band of the filter increases. Therefore, the comparator can generate a comparison result based on the signal output by the voltage divider. In addition, by implementing a protection circuit using multiple filters as shown in FIG. 2 and FIG. 3, the cost of the power supply can be reduced.

Please refer to FIG. 4, which is a circuit diagram of a filter and a voltage divider according to an embodiment of the present invention. The filter 431 shown in FIG. 4 can be used as the filter shown in FIG. 2 and FIG. 3, and the voltage divider 432 shown in FIG. 4 can be used as the voltage divider shown in FIG. 2 and FIG. 3. As shown in FIG. 4, the filter 431 has a terminal T1, and the voltage divider 432 has a terminal T2, wherein the terminal T1 is used to connect to the second conversion circuit, and the terminal T2 is used to connect to the protection circuit.

The filter 431 includes resistors 431a, 431b, 431c and 431h; capacitors 431d, 431f and 431g; and an amplifier 431e. 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 be used as a positive power supply terminal for receiving a 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.

The voltage divider 432 includes a capacitor 432a, a first voltage divider resistor 432b, a second voltage divider resistor 432c, and a diode 432d. The capacitor 432a and the second voltage divider resistor 432c are connected in parallel between one end of the first voltage divider resistor 432b and the ground GND. The other end of the first voltage divider resistor 432b is connected to the output end of the amplifier 431e. In addition, the one end of the first voltage divider 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.

其中Gain為分壓器432的增益，R ₁為第二分壓電阻器432c的電阻值，R ₂為第一分壓電阻器432b的電阻值。 In the voltage divider 432, the resistance value of the first voltage divider resistor 432b and the resistance value of the second voltage divider resistor 432c are related to the filter band of the filter 431 connected to the voltage divider 432. As described above, the gain of the voltage divider 432 can be positively correlated with the cutoff frequency of the filter band of the filter 431, and the gain of the voltage divider 432 can be calculated according to the following formula (1):

Wherein Gain is the gain of the voltage divider 432, R1 is the resistance value of the second voltage divider resistor 432c, _and R2 is the resistance value _of the first voltage divider resistor 432b.

Please refer to FIG. 5, which is a circuit diagram of a second conversion circuit according to an embodiment of the present invention. The second conversion circuit 52 shown in FIG. 5 can be used as the second conversion circuit shown in FIG. 1 to FIG. 3. As shown in FIG. 5, the second conversion circuit 52 includes a voltage converter 521, a full wave rectifier 522, a capacitor 523, and two resistors 524 and 525.

The voltage converter 521 can be a boost converter in particular. The voltage converter 521 includes a primary winding 521a and a secondary winding 521b, the primary winding 521a is connected to the first conversion circuit and the switch circuit, and the secondary winding 521b is connected to the full-wave rectifier 522. Specifically, the primary winding 521a includes terminals T4 and T5, and the secondary winding 521b includes terminals T6 and T7. In addition, the second conversion circuit 52 further includes a terminal T8 connected to the protection circuit.

The terminal T4 is connected to the switching 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 switching circuit (for example, the source of one switching transistor and the drain of another switching transistor), and the terminal T5 can be connected to the converter of the first conversion circuit.

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 diode 522d is connected to the cathode of diode 522b, and the anode of diode 522d is connected to terminal T7. The other end of resistor 522e is connected to the other end of capacitor 522f.

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

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

Please refer to FIG. 1 and FIG. 6 , wherein FIG. 6 is a flow chart of detecting power parameters according to an embodiment of the present invention. The steps of FIG. 6 can be performed by the protection circuit 13 , and in this embodiment, the protection circuit 13 can be implemented by one or more controllers or microcontrollers. As shown in FIG. 6 , detecting power parameters includes: step S1: performing spectrum conversion on the sampled current and copying to obtain multiple first spectrums; step S3: removing the spectrum corresponding to the normal frequency band in each of the multiple first spectrums to obtain multiple second spectrums; and step S5: performing inverse spectrum conversion on the multiple second spectrums to obtain the values of the multiple filtered currents as power parameters.

In step S1, the protection circuit 13 performs spectrum conversion on the sampled current output by the second conversion circuit 12, and copies the spectrum converted signal into multiple first spectrums, wherein the spectrum conversion can be a fast Fourier transform.

In step S3, the protection circuit 13 removes the spectrum corresponding to the normal frequency band in each first frequency spectrum to obtain a second frequency spectrum. The normal frequency band indicates the frequency band in which the load operates normally. By removing the spectrum corresponding to the normal frequency band, it is possible to avoid false triggering of the protection mechanism and switching the switch circuit 10 to the off state.

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

In addition, the protection circuit 13 can turn off the switch circuit 20 when the power parameter of any filter current meets the set parameter condition; turn off the switch circuit 20 when the power parameters of all filter currents meet the set parameter condition; or turn off the switch circuit 20 when the average value of the power parameters of all filter currents meets the set parameter condition. The above-mentioned set parameter meeting the condition can be, for example, greater than the predetermined parameter, less than the predetermined parameter, or equal to the predetermined parameter, and the present invention is not limited here.

The protection circuit implemented according to the embodiment of FIG6 can improve the accuracy of judging whether to turn off the switch circuit.

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 avoid the problem of false triggering of the protection mechanism, by switching the switch 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. In addition, by implementing the protection circuit with multiple 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 judging whether to turn off the switch circuit can be improved.

Although the present invention is disclosed as above by the aforementioned embodiments, it is not intended to limit the present invention. Any changes and modifications made within the spirit and scope of the present invention are within the scope of patent protection of the present invention. Please refer to the attached patent application for the scope of protection defined by the present invention.

1: Power supply

10: Switching circuit

11: First conversion circuit

12: Second conversion circuit

13: Protection circuit

IN: Input terminal

OUT: output port

Claims (8)

A power supply comprises: 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 multiple filter frequency bands different from each other to generate multiple filter currents, and when a power parameter associated with the filter currents is higher than a set parameter, the switch circuit is switched to an off state. The power supply as described in claim 1, wherein the protection circuit comprises: A plurality of filters connected to the second conversion circuit, the filters corresponding to the filter frequency bands respectively; a plurality of voltage dividers connected to the plurality of output ends of the filters respectively; a comparator connected to the plurality of output ends of the voltage dividers; and a controller connected to the output end of the comparator and the switch circuit. A power supply as described in claim 2, wherein the filters are connected in series with each other. A power supply as described in claim 2, wherein the filters are connected in parallel to each other. A power supply as described in claim 2, wherein the gain of each of the voltage dividers is related to the filter frequency bands. A power supply as described in claim 2, wherein each of the voltage dividers includes a first voltage divider resistor and a second voltage divider resistor, and the resistance value of the first voltage divider resistor and the resistance value of the second voltage divider resistor of each of the voltage dividers are related to the corresponding ones in the filtering frequency bands. The power supply as claimed in claim 1, wherein 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 switching circuit; a full-wave rectifier being connected to the secondary winding; a capacitor being 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. A power supply as described in claim 1, wherein the protection circuit comprises: A controller for performing spectrum conversion on the sampled current and replicating it to obtain a plurality of first spectrums, removing the spectrum corresponding to the normal frequency band in each of the first spectrums to obtain a plurality of second spectrums, and performing inverse spectrum conversion on the second spectrums to obtain the values of the filtered currents as the power parameters.

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