CN-122001319-A - Filter circuit, power module and server power supply

CN122001319ACN 122001319 ACN122001319 ACN 122001319ACN-122001319-A

Abstract

The invention discloses a filter circuit, a power module and a server power supply, which relate to the technical field of circuits, the filtering circuit specifically adopts a first-stage filtering module and a second-stage filtering module to carry out two-stage filtering on the feedback voltage sampled from the feedback voltage acquisition end of the load so as to improve the filtering effect on noise. Meanwhile, the cut-off frequency of the secondary filtering module is adjustable, the phase margin of the feedback loop corresponding to the feedback voltage is taken as a constraint condition in advance, the crossing frequency of the feedback loop approaches to the reference crossing frequency, and the cut-off frequency is determined in advance, so that the secondary filtering module can filter according to the noise condition in the feedback loop of the current target power supply in a targeted manner, the filtering effect of the filtering circuit on the noise is improved, the influence of the noise on the target power supply is avoided to the greatest extent, and the output voltage precision of the target power supply is improved.

Inventors

ZHANG XUELIANG
You Huijie
Xu shaoxing
LIU MEILING
LI WENFANG

Assignees

浪潮计算机科技有限公司

Dates

Publication Date: 20260508
Application Date: 20260126

Claims (10)

1. A filter circuit, comprising: the input end of the first-stage filtering module is connected with the feedback voltage acquisition end of the load corresponding to the target power supply, and is used for carrying out first-stage filtering on the feedback voltage sampled from the feedback voltage acquisition end of the load; The input end of the second-stage filtering module is connected with the output end of the first-stage filtering module, the output end of the second-stage filtering module is connected with the feedback input end of the target power supply, and the second-stage filtering module is used for carrying out second-stage filtering on the feedback voltage based on a preset cut-off frequency and outputting the feedback voltage after the filtering treatment to the target power supply; The preset cut-off frequency is determined by taking a constraint condition that the phase margin of a feedback loop corresponding to the feedback voltage is in a preset interval and taking the approach of the pass-through frequency of the feedback loop to the reference pass-through frequency as a target.
2. The filter circuit of claim 1, wherein the primary filter module comprises: The first end of the first resistor is connected with the feedback voltage acquisition positive end of the load corresponding to the target power supply; The first end of the second resistor is connected with a feedback voltage acquisition negative end of a load corresponding to the target power supply; The first end of the first capacitor is connected with the second end of the first resistor, and is used as the first output end of the first-stage filtering module, and the second end of the first capacitor is connected with the second end of the second resistor, and is used as the second output end of the first-stage filtering module.
3. The filter circuit of claim 1 or 2, wherein the secondary filter module comprises a circuit board, a third resistor disposed on the circuit board, and a second capacitor disposed on the circuit board; the third resistor and the second capacitor are connected in series, the first end of the circuit after being connected in series is used as the first input end and the first output end of the second-stage filter module, and the second end of the circuit after being connected in series is used as the second input end and the second output end of the second-stage filter module.
4. A filter circuit according to claim 3, wherein the two-stage filter module further comprises: The first end of the fourth resistor is used as a first input end of the secondary filtering module, and the second end of the fourth resistor is connected with the first end of the serially connected circuit and is used as a first output end of the secondary filtering module; and/or the number of the groups of groups, And the first end of the fifth resistor is connected with the first end of the serially connected circuit, is used as the first output end of the second-stage filtering module, and the second end of the fifth resistor is connected with the second end of the serially connected circuit, and is used as the second output end of the second-stage filtering module.
5. The filter circuit of claim 3, wherein a first reserved position and a second reserved position are arranged on the circuit board, the first reserved position is used for installing the third resistor, and the second reserved position is used for installing the second capacitor; The configuration process of the preset cut-off frequency of the secondary filtering module comprises the following steps: under the condition that the target power supply is independently powered on to work, determining the reference crossing frequency of a feedback loop corresponding to the feedback voltage; Determining an initial crossing frequency of the feedback loop under the condition that the target power supply is integrated into a target application system and the whole target application system is powered on; Taking the constraint condition that the phase margin of a feedback loop corresponding to the feedback voltage is in a preset interval and the goal that the crossing frequency of the feedback loop approaches to the reference crossing frequency, and determining the zero pole configuration of the secondary filtering module based on the initial crossing frequency and the reference crossing frequency; Determining a resistance requirement of the third resistor and/or a capacitance requirement of the second capacitor in the secondary filter module based on the determined pole-zero configuration; Selecting a resistance element according to the resistance requirement, and mounting the resistance element to the first reserved position; and selecting a capacitive element according to the capacitance requirement, and mounting the capacitive element to the second reserved position.
6. The filtering circuit of claim 5, wherein determining the pole-zero configuration of the secondary filtering module based on the initial crossover frequency and the reference crossover frequency comprises: determining a target pole frequency that adjusts the crossover frequency of the feedback loop from the initial crossover frequency to the reference crossover frequency; After the reference crossing frequency is reached, determining to adjust the phase margin of the feedback loop from the current phase margin to a target zero frequency of a preset interval.
7. The filter circuit of claim 6, wherein determining a resistance requirement of the third resistor and/or a capacitance requirement of the second capacitor in the second stage filter module based on the determined pole-zero configuration comprises: Constructing a transfer function of the secondary filtering module based on the circuit topology of the secondary filtering module; Determining a pole frequency expression and a zero frequency expression according to a transfer function of the secondary filtering module; And determining the resistance requirement of the third resistor in the secondary filtering module and/or the capacitance requirement of the second capacitor based on the pole frequency expression, the target pole frequency, the zero frequency expression and the target zero frequency.
8. The filter circuit of claim 5, wherein determining the reference crossing frequency of the feedback loop for the feedback voltage comprises: injecting a preset disturbance signal into a first preset position of a feedback loop corresponding to the feedback voltage; measuring a response signal corresponding to the preset disturbance signal output by a second preset position of the feedback loop; generating a bode plot of the feedback loop based on the preset disturbance signal and the response signal; and reading the reference crossing frequency of the feedback loop according to the Bode diagram.
9. A power supply module comprising a target power supply and a filter circuit as claimed in any one of claims 1 to 8, the filter circuit being connected in series in a voltage feedback loop of the target power supply.
10. A server power supply comprising a plurality of power modules according to claim 9.

Description

Filter circuit, power module and server power supply Technical Field The present invention relates to the field of circuit technologies, and in particular, to a filter circuit, a power module, and a server power supply. Background In order to ensure the accuracy and reliability of power supply, a remote sense line (remote sampling line) is usually set in the server power supply to detect the voltage of the load terminal, and the power supply output is regulated through voltage feedback control to ensure the voltage stability of the load terminal. However, the remote sense line is usually relatively long, so that the remote sense line is very susceptible to external electromagnetic interference, and particularly in a high-frequency switching power supply, high-frequency noise is coupled into the remote sense line, so that the output precision of the server power supply is affected. It can be seen how to avoid the influence of noise on the accurate power supply of the server power supply is a problem that needs to be solved by those skilled in the art. Disclosure of Invention The embodiment of the invention aims to provide a filter circuit, a power supply module and a server power supply, which can solve the problem that noise affects the power supply accuracy of the server power supply. In order to solve the above technical problems, an embodiment of the present invention provides a filter circuit, including: The input end of the first-stage filtering module is connected with the feedback voltage acquisition end of the load corresponding to the target power supply, and is used for carrying out first-stage filtering on the feedback voltage sampled from the feedback voltage acquisition end of the load; The input end of the second-stage filtering module is connected with the output end of the first-stage filtering module, the output end of the second-stage filtering module is connected with the feedback input end of the target power supply, and the second-stage filtering module is used for carrying out second-stage filtering on the feedback voltage based on a preset cut-off frequency and outputting the feedback voltage after the filtering treatment to the target power supply; The preset cut-off frequency is determined by taking a constraint condition that a phase margin of a feedback loop corresponding to the feedback voltage is in a preset interval and a reference cut-off frequency is approached by the cut-off frequency of the feedback loop. Optionally, the first-stage filtering module includes: The first end of the first resistor is connected with the feedback voltage acquisition positive end of the load corresponding to the target power supply; The first end of the second resistor is connected with a feedback voltage acquisition negative end of a load corresponding to the target power supply; The first end of the first capacitor is connected with the second end of the first resistor, and is used as the first output end of the first-stage filtering module, and the second end of the first capacitor is connected with the second end of the second resistor, and is used as the second output end of the first-stage filtering module. Optionally, the second-stage filtering module comprises a circuit board, a third resistor arranged on the circuit board and a second capacitor arranged on the circuit board; the third resistor and the second capacitor are connected in series, the first end of the circuit after the series connection is used as the first input end and the first output end of the second-stage filter module, and the second end of the circuit after the series connection is used as the second input end and the second output end of the second-stage filter module. Optionally, the second-stage filtering module further includes: the first end of the fourth resistor is used as a first input end of the second-stage filtering module, and the second end of the fourth resistor is connected with the first end of the serially connected circuit and is used as a first output end of the second-stage filtering module; and/or the number of the groups of groups, And the first end of the fifth resistor is connected with the first end of the circuit after being connected in series and is used as the first output end of the second-stage filtering module, and the second end of the fifth resistor is connected with the second end of the circuit after being connected in series and is used as the second output end of the second-stage filtering module. Optionally, a first reserved position and a second reserved position are arranged on the circuit board, the first reserved position is used for installing a third resistor, and the second reserved position is used for installing a second capacitor; the configuration process of the preset cut-off frequency of the secondary filtering module comprises the following steps: under the condition that the target power supply is independently electrified, determining the reference crossing freque