A multi-channel IEPE signal acquisition conditioning card and acquisition equipment

Abstract

This invention relates to a multi-channel IEPE signal acquisition and conditioning card and acquisition device. The acquisition and conditioning card includes a signal distribution area, a voltage conversion area, and an IEPE signal acquisition and processing area. The signal distribution area receives multi-channel IEPE signal outputs and outputs them to the signal acquisition and processing area. It also outputs the multi-channel IEPE acquired and processed signals obtained from the signal acquisition and processing area. An external power supply is connected to the voltage conversion area, and the converted output voltage is output. The voltage conversion area transforms the external power supply voltage, outputting it to both the IEPE signal acquisition and processing area and the signal distribution area for external power supply. The IEPE signal acquisition and processing area processes the received multi-channel IEPE signals in parallel, conditioning the unipolar signal output from the IEPE sensor into a bipolar differential signal, which is then output through the signal distribution area. This invention achieves multi-channel IEPE signal acquisition and conditioning, solving the problem of inter-channel interference.

Description

Technical Field

[0001] This invention belongs to the field of power supply technology, specifically relating to a multi-channel IEPE signal acquisition and conditioning card and acquisition device. Background Technology

[0002] Piezoelectric sensors are widely used devices with built-in voltage amplifiers, offering advantages such as high sensitivity, high bandwidth, high signal-to-noise ratio, wide operating temperature range, and high structural strength. The IEPE signal refers to the voltage output signal of the piezoelectric sensor, which is a two-wire signal; the output signal and the excitation signal share a single wire. Signal acquisition can only process single voltage or current signals and cannot process both voltage and excitation signals simultaneously. Therefore, signal conditioning is necessary.

[0003] The purpose of signal conditioning is to facilitate signal transmission and processing, making it suitable as an input signal for an A / D converter. The A / D converter converts the input voltage from an analog signal to a digital signal, which is then sent to the controller for sampling and processing, ultimately generating a real-time data waveform on the host computer.

[0004] Existing IEPE signal acquisition devices have the following drawbacks: First, most common IEPE signal acquisition devices are single-channel and cannot condition or acquire multiple IEPE signals. Second, existing multi-channel IEPE signal acquisition devices suffer from signal interference between channels, making it impossible to achieve independent acquisition and transmission between channels. Summary of the Invention

[0005] Based on the above analysis, the present invention aims to disclose a multi-channel IEPE signal acquisition and conditioning card and acquisition device, which solves the problems of mutual interference of signals and inability to achieve independent acquisition and transmission between channels when acquiring multi-channel IEPE signals.

[0006] This invention discloses a multi-channel IEPE signal acquisition and conditioning card, comprising a signal distribution area, a voltage conversion area, and an IEPE signal acquisition and processing area;

[0007] The signal distribution area is used to receive multi-channel IEPE signal outputs to the signal acquisition and processing area; and to output the multi-channel IEPE acquired and processed signals obtained from the signal acquisition and processing area; and to receive external power supply outputs to the voltage conversion area, and to output the converted external output voltage.

[0008] The voltage conversion area is used to convert the voltage of the external power supply, outputting it to the IEPE signal acquisition and processing area for power supply on the one hand, and to the signal distribution area for external power supply on the other hand.

[0009] The IEPE signal acquisition and processing area includes multiple acquisition and processing modules corresponding to the incoming multi-channel IEPE signals. The modules process the incoming multi-channel IEPE signals in parallel, conditioning the unipolar signals output by the IEPE sensors into bipolar differential signals, which are then output to the outside through the signal distribution area.

[0010] Furthermore, the acquisition and processing module in the signal distribution area includes a constant current source chip U1, a high-speed operational amplifier U2, a diode D1, resistors R1-R11, and capacitors C1-C5;

[0011] In this circuit, the positive power supply terminal V+ of the constant current source chip U1 is connected to a +24V voltage, the negative power supply terminal V- is connected to the positive terminal of diode D1, and a resistor R2 is connected between the negative power supply terminal V- and the reference voltage terminal; a resistor R3 is connected between the negative terminal of diode D1 and the reference voltage terminal R; the positive and negative terminals of the IEPE sensor output signal are connected to the two ends of a series circuit consisting of a resistor R1, a capacitor C1, and a resistor R4; the connection terminal of resistor R1 and capacitor C1 is connected to the negative terminal of diode D1, and the connection terminal of capacitor C1 and resistor R4 is connected to the positive input terminal Vin+ of high-speed operational amplifier U2 via resistor R5;

[0012] The negative input terminal Vin- of high-speed operational amplifier U2 is grounded through resistor R7, and the common-mode signal reference voltage terminal is grounded through resistor R6; the positive power supply terminal V+ is grounded through parallel capacitors C2 and C3; the negative power supply terminal V- is grounded through parallel capacitors C4 and C5; the negative output terminal is connected to the positive signal input terminal Vin+ through series resistors R9 and R8; the positive output terminal is connected to the negative signal input terminal Vin- through series resistors R10 and R11.

[0013] The connection between resistors R9 and R8 serves as the negative terminal of the differential output; the connection between resistors R10 and R11 serves as the positive terminal of the differential output.

[0014] Furthermore, the power module in the voltage conversion area includes a power regulator chip U3, a boost chip U4, a diode D2, resistors R12-R14, capacitors C6-C13, and an inductor L1;

[0015] Pins 2 and 3 of the power regulator chip U3 are connected to the negative and positive terminals of the battery, respectively. Capacitor C6 is connected between the negative and positive terminals of the battery, and capacitor C7 is connected between pins 4 and 5 of the power regulator chip U3.

[0016] The positive terminal of capacitor C6 is connected to the positive terminal of the battery, and the positive terminal of capacitor C7 is connected to pin 4 of the power regulator chip U3.

[0017] The positive terminal is connected to pin 4 of the power regulator chip and pin 5 of the boost chip U4; a resistor R12 is connected between pin 5 and pin 4 of the boost chip U4; capacitors C10 and C11 are connected between pin 5 and ground; pin 2 is grounded; an inductor L2 is connected between pin 5 and pin 1; resistor R14 is connected between pin 3 and ground; pin 1 is connected to the positive terminal of diode D2; the negative terminal of diode D2 outputs the discharge voltage.

[0018] The negative terminal of diode D2 is connected to ground by capacitors C8, C9, and C13 in parallel; the negative terminal of diode D2 is connected to pin 3 of boost chip U4 through resistor R13; resistor R13 and capacitor C12 form a parallel circuit.

[0019] Furthermore, the IEPE signal acquisition and processing area of ​​the acquisition board includes 20 acquisition and processing modules for acquiring and processing 20 IEPE signals;

[0020] The 20 acquisition and processing modules are arranged in a matrix of 5 rows and 4 columns in the IEPE signal acquisition and processing area.

[0021] Furthermore, the printed circuit board of the acquisition board has a six-layer architecture: the first layer is the device layer, the second layer is the vertical signal layer, the third layer is the horizontal signal layer, the fourth layer is the internal voltage trace layer, the fifth layer is the external voltage trace layer, and the sixth layer is the reference voltage ground plane.

[0022] Furthermore, in the device layer, components are arranged in areas divided into signal distribution area, voltage conversion area and IEPE signal acquisition and processing area. Each area does not overlap and there are no signal lines connected to each other. Copper is used to isolate the areas, and the copper width is 20mil.

[0023] In the vertical signal layer, there are only vertical signal lines, and the width and spacing of the signal lines are set to 6 mil.

[0024] In the horizontal signal layer, there are only horizontal signal lines, and the width and spacing of the signal lines are set to 6mil.

[0025] In the on-board voltage trace layer, there are only on-board voltage lines, and their line width and spacing are set to 10mil.

[0026] The voltage lines on the board are routed in a grouped manner, with five acquisition and processing modules in each column forming a group that share a single voltage bus. The voltage bus is routed between the acquisition and processing modules in two columns and bypasses the location of the differential operational amplifier.

[0027] In the external voltage trace layer, there are only external voltage traces, and their trace width and spacing are set to 10mil; the external voltage traces are only traced in the voltage conversion area.

[0028] In the reference voltage ground plane, there is only copper covering the reference voltage ground, and the area corresponding to the shape of the differential operational amplifier in the acquisition and processing module is hollowed out.

[0029] This invention also discloses a multi-channel IEPE signal acquisition device, including an IEPE signal acquisition and conditioning card, a lithium battery charging module, a power display module, a data acquisition and storage module, and an aviation plug connector;

[0030] The IEPE signal acquisition and conditioning card is a multi-channel IEPE signal acquisition and conditioning card as described in any one of claims 1-6;

[0031] The lithium battery charging module is used to realize lithium battery charging and overcharge and overcurrent protection;

[0032] The power display module is used to display the battery level;

[0033] The data acquisition and storage module is used to receive multiple differential signals output from the IEPE signal acquisition and conditioning card, and after amplification, filtering, and A / D conversion, the signals are displayed and stored by the computer.

[0034] The connector is used to connect the IEPE sensor and output the IEPE sensor information to the IEPE signal acquisition and conditioning card.

[0035] Furthermore, the lithium battery charging module includes a lithium battery charging chip U4, a diode D3, resistors R15-R18, capacitors C14-C17, and an inductor L2.

[0036] Pin 1 of the lithium battery charging chip U4 is grounded via parallel capacitors C14 and C15. Resistor R15 connects pin 1 and pin 8. Pin 1 is connected to pin 2 via resistor R18, the positive and negative terminals of LED D3. Resistor R16 connects pin 8 to ground. Pin 4 is grounded via capacitor C16, and pin 5 is grounded via capacitor C17. Inductor L2 connects pins 6 and 7, and resistor R17 connects pins 5 and 6.

[0037] The positive terminal of the external power supply for charging is connected to pin 1 of the lithium battery charging chip U4 through the positive and negative terminals of diode D3. The positive terminal of the lithium battery being charged is connected to pin 5 of the lithium battery charging chip U4, and the negative terminal is grounded.

[0038] Furthermore, the power display module includes a switch SW1 and N power display branches connected in parallel;

[0039] After switch SW1 is turned on, the N parallel power display branches are connected to the positive and negative terminals of the lithium battery respectively. When the power of the lithium battery meets the power threshold monitored by each power display branch, the light-emitting diodes in the corresponding power display branches are lit to display the remaining power of the lithium battery.

[0040] Furthermore, each power display branch includes resistors R6i, R7i, R8i, R9i, a voltage reference chip U8i, and a light-emitting diode D8i;

[0041] After the switch SW1 is turned on, the series resistors R6i and R7i are connected between the positive and negative terminals of the lithium battery, and the resistors R8i, R9i and the voltage reference chip U8i are connected in series between the positive and negative terminals of the lithium battery; the connection terminals of the resistors R6i and R7i are connected to the control terminal of the voltage reference chip U8i.

[0042] The positive terminal of the LED D8i is connected to the positive terminal of the lithium battery, and the negative terminal is connected to the connection terminals of resistors R8i and R9i; i = 1, ..., N;

[0043] The battery charge displayed in each power display branch is determined by controlling the resistance ratio of resistors R6i and R7i.

[0044] This invention can achieve at least one of the following beneficial effects:

[0045] This invention significantly reduces interference caused by the conditioning of multiple IEPE signals by isolating the IEPE sensor input signal and reducing the radiation of the operational amplifier to the ground plane. This invention also provides a high-capacity lithium battery to power the acquisition device and designs a battery conditioning circuit to achieve stable and clean power supply from the battery, while avoiding overcharging during battery charging and overcurrent and overload problems during battery discharging. Attached Figure Description

[0046] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0047] Figure 1 This is a schematic block diagram of a multi-channel IEPE signal acquisition and conditioning card in an embodiment of the present invention;

[0048] Figure 2 This is a schematic diagram of the acquisition and processing module circuit in an embodiment of the present invention;

[0049] Figure 3 This is a schematic diagram of the power module circuit in an embodiment of the present invention;

[0050] Figure 4This is a top view of the PCB of the multi-channel IEPE signal acquisition and conditioning card in an embodiment of the present invention;

[0051] Figure 5 This is a schematic diagram showing the connection of a multi-channel IEPE signal acquisition device in an embodiment of the present invention;

[0052] Figure 6 This is a circuit schematic diagram of the lithium battery charging module in an embodiment of the present invention;

[0053] Figure 7 This is a circuit diagram of the power display module for the five power display branches in an embodiment of the present invention. Detailed Implementation

[0054] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and, together with the embodiments of the present invention, serve to illustrate the principles of the present invention.

[0055] One embodiment of the present invention discloses a multi-channel IEPE signal acquisition and conditioning card; such as Figure 1 As shown, it includes a signal distribution area, a voltage conversion area, and an IEPE signal acquisition and processing area;

[0056] The signal distribution area is used to receive multi-channel IEPE signal outputs to the signal acquisition and processing area; and to output the multi-channel IEPE acquired and processed signals obtained from the signal acquisition and processing area; and to receive external power supply outputs to the voltage conversion area, and to output the converted external output voltage.

[0057] The voltage conversion area is used to convert the voltage of the external power supply, outputting it to the IEPE signal acquisition and processing area for power supply on the one hand, and to the signal distribution area for external power supply on the other hand.

[0058] The IEPE signal acquisition and processing area includes multiple acquisition and processing modules corresponding to the incoming multi-channel IEPE signals. The modules process the incoming multi-channel IEPE signals in parallel, conditioning the unipolar signals output by the IEPE sensors into bipolar differential signals, which are then output to the outside through the signal distribution area.

[0059] In one specific embodiment, the IEPE signal acquisition and processing area of ​​the acquisition board includes 20 acquisition and processing modules for acquiring and processing 20 IEPE signals.

[0060] The 20 acquisition and processing modules are arranged in a matrix of 5 rows and 4 columns in the IEPE signal acquisition and processing area.

[0061] Specifically, such as Figure 2As shown, the acquisition and processing module in the signal distribution area includes a constant current source chip U1, a high-speed operational amplifier U2, a diode D1, resistors R1-R11, and capacitors C1-C5;

[0062] In this circuit, the positive power supply terminal V+ of the constant current source chip U1 is connected to a +24V voltage, the negative power supply terminal V- is connected to the positive terminal of diode D1, and a resistor R2 is connected between the negative power supply terminal V- and the reference voltage terminal; a resistor R3 is connected between the negative terminal of diode D1 and the reference voltage terminal R; the positive and negative terminals of the IEPE sensor output signal are connected to the two ends of a series circuit consisting of a resistor R1, a capacitor C1, and a resistor R4; the connection terminal of resistor R1 and capacitor C1 is connected to the negative terminal of diode D1, and the connection terminal of capacitor C1 and resistor R4 is connected to the positive input terminal Vin+ of high-speed operational amplifier U2 via resistor R5;

[0063] The negative input terminal Vin- of high-speed operational amplifier U2 is grounded through resistor R7, and the common-mode signal reference voltage terminal is grounded through resistor R6; the positive power supply terminal V+ is connected to +5V and grounded through parallel capacitors C2 and C3; the negative power supply terminal V- is connected to -5V and grounded through parallel capacitors C4 and C5; the negative output terminal is connected to the positive signal input terminal Vin+ through series resistors R9 and R8; the positive output terminal is connected to the negative signal input terminal Vin- through series resistors R10 and R11.

[0064] The connection between resistors R9 and R8 serves as the negative terminal of the differential output; the connection between resistors R10 and R11 serves as the positive terminal of the differential output.

[0065] In the acquisition and processing module, pin 2 of the high-speed operational amplifier U2 is grounded through resistor R6. Since pin 2 is the common-mode signal reference voltage terminal used to set the output common-mode voltage, it has the potential to increase power consumption. Grounding reduces the potential difference between the input signal and the ground plane, improving measurement accuracy. By connecting the high-speed operational amplifier U2 into a fully differential amplifier architecture, the filtering function and voltage gain coupling capability are achieved. The power supply and ground terminals of the differential operational circuit are connected to C2, C3, C4, and C5 to form a two-stage low-pass filter to eliminate the influence of interference signals.

[0066] The constant current source chip U1 is an ultra-wide temperature range precision operational amplifier chip, preferably LM234; and a matching resistor R1 is added to the input terminal of the constant current source chip U1 to perform input impedance matching, thereby improving the signal-to-noise ratio of the output signal of the IEPE sensor; at the same time, the I / V conversion circuit composed of resistor R4 and capacitor C1 is added to filter out noise from the input signal and provide a low-impedance path for the output signal of the IEPE sensor.

[0067] Therefore, the acquisition and processing module in this embodiment provides constant current source excitation for the external IEPE type sensor, and realizes the conversion of current to voltage signal and the conditioning conversion of two-wire signal to differential signal. In addition, it also improves the anti-interference capability of the signal and the measurement accuracy.

[0068] To address the issue of signal interference during multi-channel IEPE signal acquisition, the printed circuit board of the acquisition board in this embodiment has a six-layer architecture. The first layer is the device layer, the second layer is the vertical signal layer, the third layer is the horizontal signal layer, the fourth layer is the internal voltage trace layer, the fifth layer is the external voltage trace layer, and the sixth layer is the reference voltage ground plane.

[0069] Specifically, in the device layer, components are arranged in areas divided into signal distribution area, voltage conversion area and IEPE signal acquisition and processing area. Each area does not overlap and there are no signal lines connected to each other. Copper is used to isolate the areas, and the copper width is 20mil.

[0070] In the vertical signal layer, there are only vertical signal lines, and the width and spacing of the signal lines are set to 6 mil.

[0071] In the horizontal signal layer, there are only horizontal signal lines, and the width and spacing of the signal lines are set to 6mil.

[0072] In the on-board voltage trace layer, there are only on-board voltage lines, and their line width and spacing are set to 10mil.

[0073] The voltage lines on the board are routed in a grouped manner, with five acquisition and processing modules in each column forming a group that share a single voltage bus. The voltage bus is routed between the acquisition and processing modules in two columns and bypasses the location of the differential operational amplifier.

[0074] In the external voltage trace layer, there are only external voltage traces, and their trace width and spacing are set to 10mil; the external voltage traces are only traced in the voltage conversion area.

[0075] In the reference voltage ground plane, there is only copper covering the reference voltage ground, and the area corresponding to the shape of the differential operational amplifier in the acquisition and processing module is hollowed out.

[0076] like Figure 3 As shown, the power module in the voltage conversion area includes a power regulator chip U3, a boost chip U4, a diode D2, resistors R12-R14, capacitors C6-C13, and an inductor L1.

[0077] Pins 2 and 3 of the power regulator chip U3 are connected to the negative and positive terminals of the battery, respectively. Capacitor C6 is connected between the negative and positive terminals of the battery, and capacitor C7 is connected between pins 4 and 5 of the power regulator chip U3.

[0078] The positive terminal of capacitor C6 is connected to the positive terminal of the battery, and the positive terminal of capacitor C7 is connected to pin 4 of the power regulator chip U3.

[0079] The positive terminal is connected to pin 4 of the power regulator chip and pin 5 of the boost chip U4; a resistor R12 is connected between pin 5 and pin 4 of the boost chip U4; capacitors C10 and C11 are connected between pin 5 and ground; pin 2 is grounded; an inductor L2 is connected between pin 5 and pin 1; resistor R14 is connected between pin 3 and ground; pin 1 is connected to the positive terminal of diode D2; the negative terminal of diode D2 outputs the discharge voltage.

[0080] The negative terminal of diode D2 is connected to ground by capacitors C8, C9, and C13 in parallel; the negative terminal of diode D2 is connected to pin 3 of boost chip U4 through resistor R13; resistor R13 and capacitor C12 form a parallel circuit.

[0081] Preferably, the power regulator chip U3 is URB2412LD-50WR3; and the boost chip U4 is LM2733.

[0082] The voltage conversion area also includes 12V to +5V and -5V power supplies, which can be implemented using existing power conversion modules.

[0083] The signal distribution area includes three signal connectors: a power strip, an input signal strip, and an output signal strip.

[0084] like Figure 4 The image shows a top view of the PCB of the multi-channel IEPE signal acquisition and conditioning card.

[0085] In summary, the multi-channel IEPE signal acquisition and conditioning card of this embodiment achieves conditioning of multiple IEPE signals, isolates the IEPE sensor input signals, reduces operational amplifier radiation to the ground plane, and significantly reduces interference generated by multi-channel IEPE signal conditioning. Furthermore, this multi-channel IEPE signal acquisition and conditioning card is modular and standardized, allowing for independent disassembly and replacement, making it more convenient to use and maintain.

[0086] This invention also discloses a multi-channel IEPE signal acquisition device; such as Figure 5 As shown, it includes an IEPE signal acquisition and conditioning card, a lithium battery charging module, a power display module, a data acquisition and storage module, and an aviation plug connector;

[0087] The IEPE signal acquisition and conditioning card is the multi-channel IEPE signal acquisition and conditioning card as described in the previous embodiment;

[0088] The multi-channel IEPE signal acquisition and conditioning card provides constant current source excitation for up to 20 external IEPE type sensors and conditions the two-wire signal into a differential signal, so that the signals between channels do not interfere with each other.

[0089] The lithium battery charging module is used to realize lithium battery charging and overcharge and overcurrent protection;

[0090] The power display module is used to display the battery level;

[0091] The data acquisition and storage module is used to receive multiple differential signals output from the IEPE signal acquisition and conditioning card, and after amplification, filtering, and A / D conversion, the signals are displayed and stored by the computer.

[0092] The connector is used to connect the IEPE sensor and output the IEPE sensor information to the IEPE signal acquisition and conditioning card.

[0093] The lithium battery charging module has an input DC charging voltage range of 12V to 20V and an output voltage isolation of 12V. It features filtering, reverse connection protection, surge protection, short circuit protection, and overvoltage protection.

[0094] Specifically, such as Figure 6 As shown, the lithium battery charging module includes a lithium battery charging chip U4, a diode D3, resistors R15-R18, capacitors C14-C17, and an inductor L2.

[0095] Pin 1 of the lithium battery charging chip U4 is grounded via parallel capacitors C14 and C15. Resistor R15 connects pin 1 and pin 8. Pin 1 is connected to pin 2 via resistor R18, the positive and negative terminals of LED D3. Resistor R16 connects pin 8 to ground. Pin 4 is grounded via capacitor C16, and pin 5 is grounded via capacitor C17. Inductor L2 connects pins 6 and 7, and resistor R17 connects pins 5 and 6.

[0096] The positive terminal of the external power supply for charging is connected to pin 1 of the lithium battery charging chip U4 through the positive and negative terminals of diode D3. The positive terminal of the lithium battery being charged is connected to pin 5 of the lithium battery charging chip U4, and the negative terminal is grounded.

[0097] The lithium battery charging chip U4 is a PW4203.

[0098] Specifically, the power display module includes a switch SW1 and N power display branches connected in parallel;

[0099] After switch SW1 is turned on, the N parallel power display branches are connected to the positive and negative terminals of the lithium battery respectively. When the power of the lithium battery meets the power threshold monitored by each power display branch, the light-emitting diodes in the corresponding power display branches are lit to display the remaining power of the lithium battery.

[0100] Each power display branch includes resistors R6i, R7i, R8i, R9i, a voltage reference chip U8i, and a light-emitting diode D8i;

[0101] After the switch SW1 is turned on, the series resistors R6i and R7i are connected between the positive and negative terminals of the lithium battery, and the resistors R8i, R9i and the voltage reference chip U8i are connected in series between the positive and negative terminals of the lithium battery; the connection terminals of the resistors R6i and R7i are connected to the control terminal of the voltage reference chip U8i.

[0102] The positive terminal of the LED D8i is connected to the positive terminal of the lithium battery, and the negative terminal is connected to the connection terminals of resistors R8i and R9i; i = 1, ..., N;

[0103] The battery charge displayed in each power display branch is determined by controlling the resistance ratio of resistors R6i and R7i.

[0104] The voltage reference chip U8i is MMTL431.

[0105] like Figure 7 As shown, a power display module including 5 power display branches is given.

[0106] The data acquisition and storage module consists of an embedded industrial computer and a data acquisition card. It receives multiple differential signals output from the IEPE signal acquisition and conditioning card, amplifies, filters, and performs A / D conversion before being displayed and stored by the computer.

[0107] The embedded industrial control computer stores and displays real-time data through encrypted communication messages, which include the channel ID of the signal and the sampling frequency.

[0108] The embedded industrial computer also has a human-machine interface, which displays real-time data waveforms, stores data, and plays back data for users.

[0109] Connect the IEPE signal acquisition and conditioning card to the aviation connector, which is connected to an external IEPE sensor. The data acquisition and storage module is connected to the output connector of the IEPE signal acquisition and conditioning card via isolated copper wires.

[0110] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-channel IEPE signal acquisition conditioning card, characterized in that, It includes a signal distribution area, a voltage conversion area, and an IEPE signal acquisition and processing area; The signal distribution area is used to receive multi-channel IEPE signal outputs to the signal acquisition and processing area. It outputs the multi-channel IEPE acquisition and processing signals obtained from the signal acquisition and processing area; it connects to an external power supply and outputs the voltage conversion area, and outputs the converted voltage to the external output area. The voltage conversion area is used to convert the voltage of the external power supply, outputting it to the IEPE signal acquisition and processing area for power supply on the one hand, and to the signal distribution area for external power supply on the other hand. The IEPE signal acquisition and processing area includes multiple acquisition and processing modules corresponding to the incoming multi-channel IEPE signals. The modules process the incoming multi-channel IEPE signals in parallel, conditioning the unipolar signal output by the IEPE sensor into a bipolar differential signal, which is then output to the outside through the signal distribution area. The acquisition and processing module in the signal distribution area includes a constant current source chip U1, a high-speed operational amplifier U2, a diode D1, resistors R1-R11, and capacitors C1-C5. In this circuit, the positive power supply terminal V+ of the constant current source chip U1 is connected to a +24V voltage, the negative power supply terminal V- is connected to the positive terminal of diode D1, and a resistor R2 is connected between the negative power supply terminal V- and the reference voltage terminal; a resistor R3 is connected between the negative terminal of diode D1 and the reference voltage terminal R; the positive and negative terminals of the IEPE sensor output signal are connected to the two ends of a series circuit consisting of a resistor R1, a capacitor C1, and a resistor R4; the connection between resistor R1 and capacitor C1 is connected to the negative terminal of diode D1, and the connection between capacitor C1 and resistor R4 is connected to the positive input terminal Vin+ of high-speed operational amplifier U2 via resistor R5; The negative input terminal Vin- of high-speed operational amplifier U2 is grounded through resistor R7, and the common-mode signal reference voltage terminal is grounded through resistor R6; the positive power supply terminal V+ is grounded through parallel capacitors C2 and C3; the negative power supply terminal V- is grounded through parallel capacitors C4 and C5; the negative output terminal is connected to the positive signal input terminal Vin+ through series resistors R9 and R8; the positive output terminal is connected to the negative signal input terminal Vin- through series resistors R10 and R11. The connection between resistors R9 and R8 serves as the negative terminal of the differential output; the connection between resistors R10 and R11 serves as the positive terminal of the differential output; in the acquisition and processing module, pin 2 of the high-speed operational amplifier U2 is grounded through resistor R6; pin 2 is the common-mode signal reference voltage terminal, and grounding reduces the potential difference between the input signal and the ground plane, thereby improving measurement accuracy; by connecting the high-speed operational amplifier U2 into a fully differential amplifier architecture, the filtering function and voltage gain coupling capability are realized, and the power supply and ground terminal of the differential operation circuit are connected to C2, C3, C4, and C5 to form a two-stage low-pass filter to eliminate the influence of interference signals; The acquisition and processing area of ​​the acquisition and conditioning card includes 20 acquisition and processing modules for the acquisition and processing of 20 IEPE signals. The 20 acquisition and processing modules are arranged in a matrix of 5 rows and 4 columns in the IEPE signal acquisition and processing area; The printed circuit board of the acquisition and conditioning card has a six-layer architecture: the first layer is the device layer, the second layer is the vertical signal layer, the third layer is the horizontal signal layer, the fourth layer is the internal voltage trace layer, the fifth layer is the external voltage trace layer, and the sixth layer is the reference voltage ground plane. In the device layer, components are arranged in areas divided into signal distribution area, voltage conversion area and IEPE signal acquisition and processing area. Each area does not overlap and there are no signal lines connected to each other. Copper is used to isolate the areas, and the copper width is 20mil. In the vertical signal layer, there are only vertical signal lines, and the width and spacing of the signal lines are set to 6 mil. In the horizontal signal layer, there are only horizontal signal lines, and the width and spacing of the signal lines are set to 6mil. In the on-board voltage trace layer, there are only on-board voltage lines, and their line width and spacing are set to 10mil. The voltage lines on the board are routed in a grouped manner, with five acquisition and processing modules in each column forming a group that share a single voltage bus. The voltage bus is routed between the acquisition and processing modules in two columns and bypasses the location of the differential operational amplifier. In the external voltage trace layer, there are only external voltage traces, and their trace width and spacing are set to 10mil; the external voltage traces are only traced in the voltage conversion area. In the reference voltage ground plane, there is only copper covering the reference voltage ground, and the area corresponding to the shape of the differential operational amplifier in the acquisition and processing module is hollowed out.

2. The multi-channel IEPE signal acquisition conditioning card of claim 1, wherein, The power module in the voltage conversion area includes a power regulator chip U3, a boost chip U4, a diode D2, resistors R12-R14, capacitors C6-C13, and an inductor L1; Pins 2 and 3 of the power regulator chip U3 are connected to the negative and positive terminals of the battery, respectively. Capacitor C6 is connected between the negative and positive terminals of the battery, and capacitor C7 is connected between pins 4 and 5 of the power regulator chip U3. The positive terminal of capacitor C6 is connected to the positive terminal of the battery, and the positive terminal of capacitor C7 is connected to pin 4 of the power regulator chip U3. The positive terminal is connected to pin 4 of the power regulator chip and pin 5 of the boost chip U4; a resistor R12 is connected between pin 5 and pin 4 of the boost chip U4; capacitors C10 and C11 are connected between pin 5 and ground; pin 2 is grounded; an inductor L2 is connected between pin 5 and pin 1; an resistor R14 is connected between pin 3 and ground; pin 1 is connected to the positive terminal of diode D2; the negative terminal of diode D2 outputs the discharge voltage. The negative terminal of diode D2 is connected to ground by capacitors C8, C9, and C13 in parallel; the negative terminal of diode D2 is connected to pin 3 of boost chip U4 through resistor R13; resistor R13 and capacitor C12 form a parallel circuit.

3. A multi-channel IEPE signal acquisition device; characterized in that, Includes IEPE signal acquisition and conditioning card, lithium battery charging module, power display module, data acquisition and storage module, and aviation connector; The IEPE signal acquisition and conditioning card is the multi-channel IEPE signal acquisition and conditioning card as described in any one of claims 1-2; The lithium battery charging module is used to realize lithium battery charging and overcharge and overcurrent protection; The power display module is used to display the battery level; The data acquisition and storage module is used to receive multiple differential signals output from the IEPE signal acquisition and conditioning card, and after amplification, filtering, and A / D conversion, the signals are displayed and stored by the computer. The connector is used to connect the IEPE sensor and output the IEPE sensor information to the IEPE signal acquisition and conditioning card.

4. The multi-channel IEPE signal acquisition device according to claim 3; characterized in that, The lithium battery charging module includes a lithium battery charging chip U4, a diode D3, resistors R15-R18, capacitors C14-C17, and an inductor L2. Pin 1 of the lithium battery charging chip U4 is grounded via parallel capacitors C14 and C15. Resistor R15 connects pin 1 and pin 8. Pin 1 is connected to pin 2 via resistor R18, the positive and negative terminals of LED D3. Resistor R16 connects pin 8 to ground. Pin 4 is grounded via capacitor C16, and pin 5 is grounded via capacitor C17. Inductor L2 connects pins 6 and 7, and resistor R17 connects pins 5 and 6. The positive terminal of the external power supply for charging is connected to pin 1 of the lithium battery charging chip U4 through the positive and negative terminals of diode D3. The positive terminal of the lithium battery being charged is connected to pin 5 of the lithium battery charging chip U4, and the negative terminal is grounded.

5. The multi-channel IEPE signal acquisition device according to claim 3; characterized in that, The power display module includes a switch SW1 and N power display branches connected in parallel; After switch SW1 is turned on, the N parallel power display branches are connected to the positive and negative terminals of the lithium battery respectively. When the power of the lithium battery meets the power threshold monitored by each power display branch, the light-emitting diodes in the corresponding power display branches are lit up to display the remaining power of the lithium battery.

6. The multi-channel IEPE signal acquisition device according to claim 5; characterized in that, Each power display branch includes resistors R6i, R7i, R8i, R9i, a voltage reference chip U8i, and a light-emitting diode D8i; After the switch SW1 is turned on, the series resistors R6i and R7i are connected between the positive and negative terminals of the lithium battery, and the resistors R8i, R9i and the voltage reference chip U8i are connected in series between the positive and negative terminals of the lithium battery; the connection terminals of the resistors R6i and R7i are connected to the control terminal of the voltage reference chip U8i. The positive terminal of the LED D8i is connected to the positive terminal of the lithium battery, and the negative terminal is connected to the connection terminals of resistors R8i and R9i; i=1,…,N; The battery charge displayed in each power display branch is determined by controlling the resistance ratio of resistors R6i and R7i.

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