Signal conditioning system for improving low-frequency measurement performance of acceleration sensor

Patent metadata

Field	Value
Publication number	US-11726108-B2
Application number	US-202117754368-A
Country	US
Kind code	B2
Filing date	Aug 27, 2021
Priority date	Aug 27, 2020
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

The present disclosure relates to a signal conditioning system for improving low-frequency measurement performance of an acceleration sensor. The signal conditioning system includes: a charge integration circuit, a high-pass filter circuit, a lead-lag network, an anti-aliasing filter circuit, and a gain adjustment circuit. An input terminal of the charge integration circuit is connected to the acceleration sensor, an output terminal of the charge integration circuit is connected to an input terminal of the high-pass filter circuit, an output terminal of the high-pass filter circuit is connected to an input terminal of the lead-lag network, an output terminal of the lead-lag network is connected to an input terminal of the anti-aliasing filter circuit, and an output terminal of the anti-aliasing filter circuit is connected to an input terminal of the gain adjustment circuit.

First claim

What is claimed is:

1. A signal conditioning system for low-frequency measurement of an acceleration sensor, comprising: a charge integration circuit, a high-pass filter circuit, a lead-lag network, an anti-aliasing filter circuit, and a gain adjustment circuit;
an input terminal of the charge integration circuit is connected to the acceleration sensor, an output terminal of the charge integration circuit is connected to an input terminal of the high-pass filter circuit, an output terminal of the high-pass filter circuit is connected to an input terminal of the lead-lag network, an output terminal of the lead-lag network is connected to an input terminal of the anti-aliasing filter circuit, and an output terminal of the anti-aliasing filter circuit is connected to an input terminal of the gain adjustment circuit;
the charge integration circuit is used to convert a charge signal generated by measurement of the acceleration sensor into a voltage signal for operational amplification; the high-pass filter circuit is used to filter a direct current (DC) component in the voltage signal for the operational amplification; the lead-lag network is used to expand a measurement bandwidth of the acceleration sensor to a low-frequency band; the anti-aliasing filter circuit is used to adjust a constraint bandwidth of an output signal; and the gain adjustment circuit is used to adjust an output gain of the output signal;
the lead-lag network comprises: a second resistor, a third resistor, a third capacitor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a fourth capacitor, and a third operational amplifier; and the second resistor, the third resistor, the fifth resistor, and the seventh resistor are all adjustable resistors; and
an input terminal of the second resistor is connected to the output terminal of the high-pass filter circuit, an output terminal of the second resistor is connected to an input terminal of the third resistor and an input terminal of the fourth resistor respectively, an output terminal of the third resistor is connected to an input terminal of the third capacitor, an output terminal of the third capacitor is grounded, an output terminal of the fourth resistor is connected to an input terminal of the fifth resistor and a second input terminal of the third operational amplifier respectively, an output terminal of the fifth resistor is connected to an input terminal of the seventh resistor and an input terminal of the fourth capacitor respectively, an output terminal of the seventh resistor and an output terminal of the fourth capacitor are both connected to an output terminal of the third operational amplifier, the output terminal of the third operational amplifier is further connected to the anti-aliasing filter circuit, one terminal of the sixth resistor is connected to a first input terminal of the third operational amplifier, and the other terminal of the sixth resistor is grounded.

2. The signal conditioning system for low-frequency measurement of an acceleration sensor according to claim 1 , wherein the charge integration circuit comprises: a first capacitor and a first operational amplifier; and
an input terminal of the first capacitor and a second input terminal of the first operational amplifier are both connected to the acceleration sensor, and an output terminal of the first capacitor and an output terminal of the first operational amplifier are both connected to the input terminal of the high-pass filter circuit; and a first input terminal of the first operational amplifier is grounded.

3. The signal conditioning system for low-frequency measurement of an acceleration sensor according to claim 1 , wherein the high-pass filter circuit comprises: a second capacitor, a first resistor, and a second operational amplifier; and
an input terminal of the second capacitor is connected to the output terminal of the charge integration circuit, an output terminal of the second capacitor is connected to an input terminal of the first resistor and a first input terminal of the second operational amplifier respectively, an output terminal of a first capacitor is grounded, a second input terminal of the second operational amplifier is connected to an output terminal of the second operational amplifier, and the output terminal of the second operational amplifier is further connected to the input terminal of the lead-lag network.

4. The signal conditioning system for low-frequency measurement of an acceleration sensor according to claim 3 , wherein a transfer function of the high-pass filter circuit is determined by a formula

H

1
⁢
0
⁢
2

=

s

s
+

1

R
1

⁢

C
2

,

s is a complex variable, represents a complex frequency, and is obtained by performing Laplace transform on a differential equation of a circuit model, R 1 is a value of the first resistor, and C 2 is a value of the second capacitor.

5. The signal conditioning system for low-frequency measurement of an acceleration sensor according to claim 1 , wherein a transfer function of the lead-lag network is determined by a formula

H

1
⁢
0
⁢
3

=

R
3

⁢

R
5

⁢

C
3

(

R
2

+

R
3

)

⁢

R
4

⁢

C
3

·

s
+

1

R
3

⁢

C

Assignees

• Univ Shanghai

Inventors

• Pu Huayan
• Jiang Peng
• Ding Jiheng
• Sun Yi
• Wang Min
• Peng Yan
• Luo Jun
• Xie Shaorong

Classifications

• G01P21/00 Primary

  Testing or calibrating of apparatus or devices covered by the preceding groups · CPC title