阅读说明：本技术 一种双线圈组滑油屑末在线监测系统 (Last on-line monitoring system of twin coil group lubricating oil bits ) 是由 熊志刚 张增增 李�昊 王旭峰 于 2020-05-28 设计创作，主要内容包括：本发明公开了一种双线圈组滑油屑末在线监测系统,包括电源模块、传感器模块、信号解调模块和上位机,特点是电源模块设置有第一正电压输出端、负电压输出端、第二正电压输出端和第三正电压输出端,传感器模块包括用于产生传感器激励信号的传感器驱动模块、第一激励模块、第一感应模块、第二激励模块和第二感应模块,信号解调模块包括第一差分放大模块、第一相敏解调模块、第一低通滤波模块、第一超级伺服放大器模块、第二差分放大模块、第二相敏解调模块、第二低通滤波模块、第二超级伺服放大器模块、AD采样模块和DSP控制模块；优点是信号解调模块一共两路,有效减小漏检率,提升检测结果可靠性,且检测效率和检测精度较高。(The invention discloses a double-coil group lubricating oil scrap online monitoring system which comprises a power module, a sensor module, a signal demodulation module and an upper computer, and is characterized in that the power module is provided with a first positive voltage output end, a negative voltage output end, a second positive voltage output end and a third positive voltage output end, the sensor module comprises a sensor driving module, a first excitation module, a first induction module, a second excitation module and a second induction module, wherein the sensor driving module is used for generating a sensor excitation signal; the advantages are that the signal demodulation modules have two paths in total, effectively reducing the missing rate, improving the reliability of the detection result, and having higher detection efficiency and detection precision.)

1. The double-coil group lubricating oil crumb on-line monitoring system comprises a power module, a sensor module, a signal demodulation module and an upper computer, and is characterized in that the power module is provided with a first positive voltage output end, a negative voltage output end, a second positive voltage output end and a third positive voltage output end, the sensor module comprises a sensor driving module, a first excitation module, a first induction module, a second excitation module and a second induction module, the sensor driving module is used for generating a sensor excitation signal, the signal demodulation module comprises a first differential amplification module, a first phase-sensitive demodulation module, a first low-pass filtering module, a first super servo amplifier module, a second differential amplification module, a second phase-sensitive demodulation module, a second low-pass filtering module, a second super servo amplifier module, an AD sampling module and a DSP control module, and the first excitation module comprises a first coil, a second coil, a third coil and a fourth coil, wherein the second coil is, The second excitation module comprises a fourth coil, a fifth coil and a third capacitor, the second induction module comprises a sixth coil and a fourth capacitor, the second coil, the third coil, the first coil, the fifth coil, the sixth coil and the fourth coil are sequentially wound outside the oil pipe at intervals from front to back, the DSP control module sends a first PWM signal to the input end of the sensor driving module through a first PWM signal output end, the excitation signal output end of the sensor driving module, one end of the first capacitor, one end of the third capacitor, one end of the first coil and one end of the fourth coil are connected, and the other end of the first coil is connected with one end of the second coil, the other end of the fourth coil is connected to one end of the fifth coil, the other end of the first capacitor, the other end of the third capacitor, the other end of the second coil, the other end of the fifth coil and the first positive voltage output end of the power module are connected, one end of the third coil, one end of the second capacitor and the first input end of the first differential amplification module are connected, the other end of the third coil, the other end of the second capacitor and the second input end of the first differential amplification module are connected, the output end of the first differential amplification module is connected to the first signal input end of the first phase-sensitive demodulation module, and the DSP control module sends a second PWM signal to the second signal input end of the first phase-sensitive demodulation module through the second PWM signal output end, the output end of the first phase-sensitive demodulation module is connected with the input end of the first low-pass filter module, the output end of the first low-pass filter module is connected with the input end of the first super servo amplifier module, the output end of the first super servo amplifier module is connected with the first input end of the AD sampling module, one end of the sixth coil, one end of the fourth capacitor and the first input end of the second differential amplification module are connected, the other end of the sixth coil, the other end of the fourth capacitor and the second input end of the second differential amplification module are connected, the output end of the second differential amplification module is connected with the first signal input end of the second phase-sensitive demodulation module, and the DSP control module sends a second PWM signal to the second signal input end of the second phase-sensitive demodulation module through the second PWM signal output end, the output end of the second phase-sensitive demodulation module is connected with the input end of the second low-pass filtering module, the output end of the second low-pass filtering module is connected with the input end of the second super servo amplifier module, the output end of the second super servo amplifier module is connected with the second input end of the AD sampling module, the AD sampling signal output end of the AD sampling module is correspondingly connected with the AD sampling signal input end of the DSP control module, and the DSP control module is connected with the upper computer through a communication module.

2. The dual-coil group grease debris on-line monitoring system according to claim 1, wherein the second differential amplification module has the same structure as the first differential amplification module, the first differential amplification module comprises a first operational amplifier, a second operational amplifier, a third operational amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a fifth capacitor and a sixth capacitor, one end of the first resistor is connected with one end of the second capacitor, one end of the second resistor is connected with the other end of the second capacitor, the other end of the first resistor, the positive input end of the first operational amplifier and one end of the fifth capacitor are connected, and the other end of the second resistor, the positive input end of the first operational amplifier and one end of the fifth capacitor are connected, The other end of the fifth capacitor is connected to the positive input terminal of the second operational amplifier, the negative input terminal of the first operational amplifier, one end of the fourth resistor and one end of the fifth resistor are connected, the other end of the fifth resistor is connected to one end of the sixth resistor, the other end of the sixth resistor, one end of the seventh resistor and the negative input terminal of the second operational amplifier are connected, the other end of the fourth resistor, the output terminal of the first operational amplifier and one end of the third resistor are connected, the other end of the seventh resistor, the output terminal of the second operational amplifier and one end of the eighth resistor are connected, the other end of the third resistor, one end of the ninth resistor, one end of the eleventh resistor, one end of the sixth capacitor and the negative input terminal of the third operational amplifier are connected, the other end of the ninth resistor and one end of the tenth resistor are both grounded, the other end of the eighth resistor, the other end of the tenth resistor and the positive input end of the third operational amplifier are connected, and the other end of the sixth capacitor, the other end of the eleventh resistor, the other end of the third operational amplifier and the first signal input end of the first phase-sensitive demodulation module are connected.

3. The dual-coil-set grease crumbs on-line monitoring system as claimed in claim 1, wherein the first phase-sensitive demodulation module and the second phase-sensitive demodulation module have the same structure, the first phase-sensitive demodulation module comprises a phase-locked amplifier with model number AD630AR, a twelfth resistor and a thirteenth resistor, one end of the twelfth resistor is connected with the output end of the first differential amplification module, the other end of the twelfth resistor, the 1 st pin of the phase-locked amplifier and the 16 th pin of the phase-locked amplifier are connected, the 8 th pin of the phase-locked amplifier is connected with the negative voltage output end of the power module, the 9 th pin, the 14 th pin and the 17 th pin of the phase-locked amplifier are all grounded, the 10 th pin of the phase-locked amplifier is connected with the second PWM signal output end of the DSP control module, the 11 th pin of the phase-locked amplifier is connected with the first positive voltage output end of the power supply module, the 13 th pin of the phase-locked amplifier is connected with one end of the thirteenth resistor, the other end of the thirteenth resistor is connected with the input end of the first low-pass filtering module, and the 15 th pin, the 19 th pin and the 20 th pin of the phase-locked amplifier are connected.

4. A double-coil-set oil debris on-line monitoring system as claimed in claim 1, wherein the first low-pass filtering module and the second low-pass filtering module have the same structure, the first low-pass filtering module comprises a fourteenth resistor, a fifteenth resistor, a seventh capacitor, an eighth capacitor, a ninth capacitor and a fourth operational amplifier, one end of the fourteenth resistor is connected with the output end of the first phase-sensitive demodulation module, the other end of the fourteenth resistor, one end of the fifteenth resistor, one end of the seventh capacitor and one end of the eighth capacitor are connected, the other end of the seventh capacitor, the other end of the eighth capacitor, the negative input end of the fourth operational amplifier, the output end of the fourth operational amplifier and the input end of the first super-servo amplifier module are connected, the other end of the fifteenth resistor, one end of the ninth capacitor and the positive input end of the fourth operational amplifier are connected, and the other end of the ninth capacitor is grounded.

5. A dual-coil-set grease debris on-line monitoring system as claimed in claim 1, wherein the first super servo amplifier module and the second super servo amplifier module have the same structure, the first super servo amplifier module comprises a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor, a twenty-second resistor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, a fifth operational amplifier and a sixth operational amplifier, one end of the sixteenth resistor is connected with the output end of the first low-pass filter module, the other end of the sixteenth resistor, one end of the seventeenth resistor, one end of the tenth capacitor and the negative input end of the fifth operational amplifier are connected, and the other end of the seventeenth resistor, The other end of the tenth capacitor, one end of the nineteenth resistor, the output end of the fifth operational amplifier and the first input end of the AD sampling module are connected, the positive input end of the fifth operational amplifier is connected with one end of the eighteenth resistor, the other end of the eighteenth resistor, one end of the eleventh capacitor and the output end of the sixth operational amplifier are connected, the other end of the eleventh capacitor, one end of the twentieth resistor and the negative input end of the sixth operational amplifier are connected, the positive input end of the sixth operational amplifier, one end of the twenty-second resistor and one end of the twelfth capacitor are connected, the other end of the nineteenth resistor, the other end of the twentieth resistor and one end of the twenty-first resistor are connected, the other end of the twenty-first resistor, the output end of the fifth operational amplifier and the first input end of the AD sampling module are connected, the positive input end of the fifth operational amplifier, one end of the eleventh capacitor, one end of, The other end of the twenty-second resistor and the other end of the twelfth capacitor are both grounded.

6. The double-coil-group grease debris on-line monitoring system according to claim 3, wherein the AD sampling module comprises an AD conversion chip with a model number of AD7890, a thirteenth capacitor, a fourteenth capacitor, a fifteenth capacitor, a sixteenth capacitor, an electrolytic capacitor and a twenty-third resistor, the DSP control module comprises a DSP chip with a model number of TMS320F28335, a twenty-fourth resistor, a twenty-fifth resistor, a twenty-sixth resistor, a twenty-seventh resistor, a twenty-eighth resistor, a twenty-ninth resistor, a thirty-eleventh resistor, a thirty-second resistor, a thirty-third resistor, a thirty-fourth resistor, a seventeenth capacitor, an eighteenth capacitor and a first NMOS (N-channel metal oxide semiconductor) tube, the 1 st pin, the 3 rd pin, the 15 th pin, the 21 st pin, the 22 th pin and the 23 th pin of the AD conversion chip are all grounded, and the 2 nd pin, the thirteenth pin, the twenty-fourth pin, the fifteenth and the twenty-third pins of the AD conversion chip are, One end of the thirteenth capacitor is connected to the second positive voltage output terminal of the power module, the other end of the thirteenth capacitor is grounded, the 4 th pin of the AD conversion chip is connected to one end of the fourteenth capacitor, the other end of the fourteenth capacitor is grounded, the 5 th pin of the AD conversion chip is connected to one end of the twenty-seventh resistor, the 6 th pin of the AD conversion chip is connected to one end of the twenty-sixth resistor, the 7 th pin of the AD conversion chip is connected to one end of the thirty-second resistor, the 8 th pin and the 9 th pin of the AD conversion chip are connected to one end of the thirty-third resistor, the 10 th pin of the AD conversion chip is connected to one end of the thirty-first resistor, and the 11 th pin of the AD conversion chip is connected to one end of the twenty-eighth resistor, a 12 th pin of the AD conversion chip, one end of the twenty-third resistor, one end of the fifteenth capacitor and the anode of the electrolytic capacitor are connected, the other end of the twenty-third resistor is connected with the second positive voltage output end of the power module, the other end of the fifteenth capacitor and the cathode of the electrolytic capacitor are respectively grounded, a 13 th pin of the AD conversion chip is connected with a 14 th pin, a 19 th pin of the AD conversion chip is connected with the output end of the second super servo amplifier module, a 20 th pin of the AD conversion chip is connected with the output end of the first super servo amplifier module, a 24 th pin of the AD conversion chip is connected with one end of the sixteenth capacitor, and the other end of the sixteenth capacitor is grounded;

the 5 th pin of the DSP chip is connected with one end of the twenty-fourth resistor, the other end of the twenty-fourth resistor is connected with the input end of the sensor driving module, the 7 th pin of the DSP chip is connected with one end of the twenty-fifth resistor, the other end of the twenty-fifth resistor is connected with the 10 th pin of the phase-locked amplifier, the 13 th pin of the DSP chip is connected with the other end of the twenty-sixth resistor, the 16 th pin of the DSP chip is connected with the other end of the twenty-seventh resistor, the 21 st pin of the DSP chip is connected with the other end of the twenty-eighth resistor, the 24 th pin of the DSP chip, one end of the twenty-ninth resistor and the drain electrode of the first NMOS tube are connected, and the other end of the twenty-ninth resistor is connected with the third positive voltage output end of the power module, the source electrode of the first NMOS tube is grounded, the grid electrode of the first NMOS tube, the other end of the thirty-first resistor and one end of the thirty-first resistor are connected, the other end of the thirty-first resistor is grounded, the 25 th pin of the DSP chip is connected with the other end of the thirty-second resistor, the 26 th pin of the DSP chip is connected with the other end of the thirty-third resistor, the 55 th pin of the DSP chip is connected with one end of the seventeenth capacitor, the 56 th pin of the DSP chip is connected with one end of the eighteenth capacitor, the 57 th pin of the DSP chip is connected with one end of the thirty-fourth resistor, the 43 th pin, the 54 th pin of the DSP chip, the other end of the seventeenth capacitor, the other end of the eighteenth capacitor and the other end of the thirty-fourth resistor are all grounded, the 2 nd pin of the DSP chip is used as a transmission outlet connected with the communication module, and the 141 nd pin of the DSP chip is used as a transmission inlet connected with the communication module.

7. The dual-coil-set grease crumbs on-line monitoring system as claimed in claim 1, wherein the sensor driving module comprises a thirty-fifth resistor, a thirty-sixth resistor, a thirty-seventh resistor and a second NMOS transistor, one end of the thirty-fifth resistor is connected to the first PWM signal output terminal of the DSP control module, the other end of the thirty-fifth resistor, one end of the thirty-sixth resistor and the gate of the second NMOS transistor are connected, the other end of the thirty-sixth resistor and the drain of the second NMOS transistor are all grounded, the source of the second NMOS transistor is connected to one end of the thirty-seventh resistor, and the other end of the thirty-seventh resistor is connected to one end of the first capacitor.

8. The dual-coil group grease debris on-line monitoring system as recited in claim 1, wherein the output voltage of the first positive voltage output terminal of the power module is 15V, the output voltage of the negative voltage output terminal of the power module is-15V, the output voltage of the second positive voltage output terminal of the power module is 5V, and the output voltage of the third positive voltage output terminal of the power module is 3.3V.

Technical Field

The invention relates to an online monitoring system, in particular to an online monitoring system for lubricating oil scraps of a double-coil group.

Background

When the engine is used, because all parts are easy to wear during operation, the service life of the engine is shortened, and the maintenance cost of the engine is increased; at present, the abrasion condition of equipment can be detected in time by detecting and analyzing particles in oil in an engine and a hydraulic system, so that faulty equipment can be found in time.

Most of the existing detection methods regularly collect oil and send the oil to a designated detection place for off-line detection, so that faults cannot be found in time; the device has higher cost, and the technology is originated from airplanes and large-scale engines, relates to the core technology of the national aviation industry, restricts the application of foreign technologies in China, and develops the research on the online detection technology of metal scraps in oil in nearly five years in China, and the technology is still in the principle experiment stage.

Disclosure of Invention

The invention aims to provide the double-coil group lubricating oil scrap on-line monitoring system which is high in detection precision and reliable in detection result.

The technical scheme adopted by the invention for solving the technical problems is as follows: a double-coil group lubricating oil crumb on-line monitoring system comprises a power module, a sensor module, a signal demodulation module and an upper computer, wherein the power module is provided with a first positive voltage output end, a negative voltage output end, a second positive voltage output end and a third positive voltage output end, the sensor module comprises a sensor driving module, a first excitation module, a first induction module, a second excitation module and a second induction module which are used for generating a sensor excitation signal, the signal demodulation module comprises a first differential amplification module, a first phase-sensitive demodulation module, a first low-pass filtering module, a first super servo amplifier module, a second differential amplification module, a second phase-sensitive demodulation module, a second low-pass filtering module, a second super servo amplifier module, an AD sampling module and a DSP control module,

the first excitation module comprises a first coil, a second coil and a first capacitor, the first induction module comprises a third coil and a second capacitor, the second excitation module comprises a fourth coil, a fifth coil and a third capacitor, the second induction module comprises a sixth coil and a fourth capacitor, the second coil, the third coil, the first coil, the fifth coil, the sixth coil and the fourth coil are sequentially wound outside the oil pipe at intervals from front to back,

the DSP control module sends a first PWM signal to the input end of the sensor driving module through a first PWM signal output end, the excitation signal output end of the sensor driving module, one end of the first capacitor, one end of the third capacitor, one end of the first coil and one end of the fourth coil are connected, the other end of the first coil is connected with one end of the second coil, the other end of the fourth coil is connected with one end of the fifth coil, the other end of the first capacitor, the other end of the third capacitor, the other end of the second coil, the other end of the fifth coil and the first positive voltage output end of the power module are connected,

one end of the third coil, one end of the second capacitor and the first input end of the first differential amplification module are connected, the other end of the third coil, the other end of the second capacitor and the second input end of the first differential amplification module are connected, the output end of the first differential amplification module is connected with the first signal input end of the first phase-sensitive demodulation module, the DSP control module sends a second PWM signal to the second signal input end of the first phase-sensitive demodulation module through the second PWM signal output end, the output end of the first phase-sensitive demodulation module is connected with the input end of the first low-pass filter module, the output end of the first low-pass filter module is connected with the input end of the first super servo amplifier module, the output end of the first super servo amplifier module is connected with the first input end of the AD sampling module,

one end of the sixth coil, one end of the fourth capacitor and the first input end of the second differential amplification module are connected, the other end of the sixth coil, the other end of the fourth capacitor and the second input end of the second differential amplification module are connected, the output end of the second differential amplification module is connected with the first signal input end of the second phase-sensitive demodulation module, the DSP control module sends a second PWM signal to the second signal input end of the second phase-sensitive demodulation module through the second PWM signal output end, the output end of the second phase-sensitive demodulation module is connected with the input end of the second low-pass filter module, the output end of the second low-pass filter module is connected with the input end of the second super servo amplifier module, and the output end of the second super servo amplifier module is connected with the second input end of the AD sampling module, AD sampling signal output of AD sampling module with DSP control module's AD sampling signal input correspond and be connected, DSP control module pass through communication module with the host computer connect.

The second differential amplification module has the same structure as the first differential amplification module, the first differential amplification module comprises a first operational amplifier, a second operational amplifier, a third operational amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a fifth capacitor and a sixth capacitor, one end of the first resistor is connected with one end of the second capacitor, one end of the second resistor is connected with the other end of the second capacitor, the other end of the first resistor, the positive input end of the first operational amplifier and one end of the fifth capacitor are connected, the other end of the second resistor, the other end of the fifth capacitor and the positive input end of the second operational amplifier are connected, the negative input terminal of the first operational amplifier, one end of the fourth resistor and one end of the fifth resistor are connected, the other end of the fifth resistor is connected to one end of the sixth resistor, the other end of the sixth resistor, one end of the seventh resistor and the negative input terminal of the second operational amplifier are connected, the other end of the fourth resistor, the output terminal of the first operational amplifier and one end of the third resistor are connected, the other end of the seventh resistor, the output terminal of the second operational amplifier and one end of the eighth resistor are connected, the other end of the third resistor, one end of the ninth resistor, one end of the eleventh resistor, one end of the sixth capacitor and the negative input terminal of the third operational amplifier are connected, and the other end of the ninth resistor, one end of the sixth resistor and one end of the eighth resistor are connected, One end of the tenth resistor is grounded, the other end of the eighth resistor, the other end of the tenth resistor and the positive input end of the third operational amplifier are connected, and the other end of the sixth capacitor, the other end of the eleventh resistor, the other end of the third operational amplifier and the first signal input end of the first phase-sensitive demodulation module are connected. The second differential amplification module and the first differential amplification module both adopt a three-operational-amplifier amplification circuit structure similar to an instrument amplifier.

The structure of the first phase-sensitive demodulation module is the same as that of the second phase-sensitive demodulation module, the first phase-sensitive demodulation module comprises a phase-locked amplifier with the model number of AD630AR, a twelfth resistor and a thirteenth resistor, one end of the twelfth resistor is connected with the output end of the first differential amplification module, the other end of the twelfth resistor, a 1 st pin of the phase-locked amplifier and a 16 th pin of the phase-locked amplifier are connected, an 8 th pin of the phase-locked amplifier is connected with the negative voltage output end of the power supply module, a 9 th pin, a 14 th pin and a 17 th pin of the phase-locked amplifier are all grounded, a 10 th pin of the phase-locked amplifier is connected with the second PWM signal output end of the DSP control module, an 11 th pin of the phase-locked amplifier is connected with the first positive voltage output end of the power supply module, and a 13 th pin of the phase-locked amplifier is connected with one end of the thirteenth resistor, the other end of the thirteenth resistor is connected with the input end of the first low-pass filtering module, and a 15 th pin, a 19 th pin and a 20 th pin of the phase-locked amplifier are connected.

The first low-pass filter module and the second low-pass filter module have the same structure, the first low-pass filter module includes a fourteenth resistor, a fifteenth resistor, a seventh capacitor, an eighth capacitor, a ninth capacitor and a fourth operational amplifier, one end of the fourteenth resistor is connected to the output end of the first phase-sensitive demodulation module, the other end of the fourteenth resistor, one end of the fifteenth resistor, one end of the seventh capacitor and one end of the eighth capacitor are connected, the other end of the seventh capacitor, the other end of the eighth capacitor, the negative input end of the fourth operational amplifier, the output end of the fourth operational amplifier and the input end of the first super servo amplifier module are connected, the other end of the fifteenth resistor, one end of the ninth capacitor and the positive input end of the fourth operational amplifier are connected, the other end of the ninth capacitor is grounded.

The first super servo amplifier module and the second super servo amplifier module have the same structure, the first super servo amplifier module comprises a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor, a twenty-second resistor, a tenth capacitor, an eleventh capacitor, a twelfth capacitor, a fifth operational amplifier and a sixth operational amplifier, one end of the sixteenth resistor is connected with the output end of the first low-pass filter module, the other end of the sixteenth resistor, one end of the seventeenth resistor, one end of the tenth capacitor and the negative input end of the fifth operational amplifier are connected, the other end of the seventeenth resistor, the other end of the tenth capacitor, one end of the nineteenth resistor, the output end of the fifth operational amplifier and the first input end of the AD sampling module are connected, the positive input end of the fifth operational amplifier is connected with one end of the eighteenth resistor, the other end of the eighteenth resistor, one end of the eleventh capacitor and the output end of the sixth operational amplifier are connected, the other end of the eleventh capacitor, one end of the twentieth resistor and the negative input end of the sixth operational amplifier are connected, the positive input end of the sixth operational amplifier, one end of the twenty-second resistor and one end of the twelfth capacitor are connected, the other end of the nineteenth resistor, the other end of the twentieth resistor and one end of the twenty-first resistor are connected, and the other end of the twenty-first resistor, the other end of the twenty-second resistor and the other end of the twelfth capacitor are all grounded.

The AD sampling module comprises an AD conversion chip with the model number of AD7890, a thirteenth capacitor, a fourteenth capacitor, a fifteenth capacitor, a sixteenth capacitor, an electrolytic capacitor and a twenty-third resistor, the DSP control module comprises a DSP chip with the model number of TMS320F28335, a twenty-fourth resistor, a twenty-fifth resistor, a twenty-sixth resistor, a twenty-seventh resistor, a twenty-eighth resistor, a twenty-ninth resistor, a thirty-fifth resistor, a thirty-eleventh resistor, a thirty-second resistor, a thirty-third resistor, a thirty-fourth resistor, a seventeenth capacitor, an eighteenth capacitor and a first NMOS (N-channel metal oxide semiconductor) tube, a 1 st pin, a 3 rd pin, a 15 th pin, a 21 st pin, a 22 nd pin and a 23 rd pin of the AD conversion chip are all grounded, a 2 nd pin of the AD conversion chip and one end of the thirteenth capacitor are respectively connected with a second positive voltage output end of the power supply module, the other end of the thirteenth capacitor is grounded, the 4 th pin of the AD conversion chip is connected with one end of the fourteenth capacitor, the other end of the fourteenth capacitor is grounded, the 5 th pin of the AD conversion chip is connected with one end of the twenty-seventh resistor, the 6 th pin of the AD conversion chip is connected with one end of the twenty-sixth resistor, the 7 th pin of the AD conversion chip is connected with one end of the thirty-second resistor, the 8 th pin and the 9 th pin of the AD conversion chip are connected with one end of the thirty-third resistor, the 10 th pin of the AD conversion chip is connected with one end of the thirty-third resistor, the 11 th pin of the AD conversion chip is connected with one end of the twenty-eighth resistor, the 12 th pin of the AD conversion chip and one end of the twenty-third resistor, One end of the fifteenth capacitor is connected with the positive electrode of the electrolytic capacitor, the other end of the twenty-third resistor is connected with the second positive voltage output end of the power module, the other end of the fifteenth capacitor and the negative electrode of the electrolytic capacitor are respectively grounded, the 13 th pin of the AD conversion chip is connected with the 14 th pin, the 19 th pin of the AD conversion chip is connected with the output end of the second super servo amplifier module, the 20 th pin of the AD conversion chip is connected with the output end of the first super servo amplifier module, the 24 th pin of the AD conversion chip is connected with one end of the sixteenth capacitor, and the other end of the sixteenth capacitor is grounded;

the 5 th pin of the DSP chip is connected with one end of the twenty-fourth resistor, the other end of the twenty-fourth resistor is connected with the input end of the sensor driving module, the 7 th pin of the DSP chip is connected with one end of the twenty-fifth resistor, the other end of the twenty-fifth resistor is connected with the 10 th pin of the phase-locked amplifier, the 13 th pin of the DSP chip is connected with the other end of the twenty-sixth resistor, the 16 th pin of the DSP chip is connected with the other end of the twenty-seventh resistor, the 21 st pin of the DSP chip is connected with the other end of the twenty-eighth resistor, the 24 th pin of the DSP chip, one end of the twenty-ninth resistor and the drain electrode of the first NMOS tube are connected, and the other end of the twenty-ninth resistor is connected with the third positive voltage output end of the power module, the source electrode of the first NMOS tube is grounded, the grid electrode of the first NMOS tube, the other end of the thirty-first resistor and one end of the thirty-first resistor are connected, the other end of the thirty-first resistor is grounded, the 25 th pin of the DSP chip is connected with the other end of the thirty-second resistor, the 26 th pin of the DSP chip is connected with the other end of the thirty-third resistor, the 55 th pin of the DSP chip is connected with one end of the seventeenth capacitor, the 56 th pin of the DSP chip is connected with one end of the eighteenth capacitor, the 57 th pin of the DSP chip is connected with one end of the thirty-fourth resistor, the 43 th pin, the 54 th pin of the DSP chip, the other end of the seventeenth capacitor, the other end of the eighteenth capacitor and the other end of the thirty-fourth resistor are all grounded, the 2 nd pin of the DSP chip is used as a transmission outlet connected with the communication module, and the 141 nd pin of the DSP chip is used as a transmission inlet connected with the communication module.

The sensor driving module comprises a thirty-fifth resistor, a thirty-sixth resistor, a thirty-seventh resistor and a second NMOS (N-channel metal oxide semiconductor) tube, one end of the thirty-fifth resistor is connected with the first PWM (pulse-width modulation) signal output end of the DSP control module, the other end of the thirty-fifth resistor, one end of the thirty-sixth resistor and the grid electrode of the second NMOS tube are connected, the other end of the thirty-sixth resistor and the drain electrode of the second NMOS tube are grounded, the source electrode of the second NMOS tube is connected with one end of the thirty-seventh resistor, and the other end of the thirty-seventh resistor is connected with one end of the first capacitor.

The output voltage of the first positive voltage output end of the power module is 15V, the output voltage of the negative voltage output end of the power module is-15V, the output voltage of the second positive voltage output end of the power module is 5V, and the output voltage of the third positive voltage output end of the power module is 3.3V.

Compared with the prior art, the oil-liquid particle detection device has the advantages that the whole body comprises two parts, the first part is a double-coil-group sensor consisting of three coils in each group, the second part is a signal demodulation module, when particles in oil liquid pass through the sensor, the sensor collects weak voltage signals, the signals are transmitted to the DSP control module for processing through a subsequent demodulation and amplification circuit, the DSP control module feeds the processed signals back to the upper computer through the communication module in real time, and the upper computer displays the attributes, sizes and qualities of the detected particles in real time, so that man-machine interaction is realized; the signal demodulation module has two paths in total, each path corresponds to a group of three coils, even if one path of missing detection is detected, the other group of the missing detection signals is sent, the missing detection rate is effectively reduced, the reliability of the detection result is improved, the detection process is online real-time detection, the detection efficiency is higher, the overall structure is simpler, and the cost is saved.

Wherein, the DSP chip generates a first PWM signal which can be set to be a PWM square wave signal with the frequency of 100K and the duty ratio of 25 percent, the first PWM signal is sent to the sensor driving module through the first PWM signal output end, the sensor driving module generates a sensor excitation signal to drive the sensor to normally work, the sensor detection principle is mainly to establish a current-carrying coil magnetic field intensity model according to the Biao-Saval principle, then the induction electromotive force is in direct proportion to the change rate of the magnetic flux according to the electromagnetic induction law, two side coils of each group of three coils are used as excitation coils to play a balancing role, the middle coil is used as an induction coil, when metal particles or nonmetal enters the coils, the balanced magnetic fields of the left side and the right side are disturbed, so as to generate corresponding induction electromotive force, because the roles of ferromagnetic particles and non-ferromagnetic particles are opposite, therefore, the attribute of the particles can be judged according to the phase of the output voltage, and the mass of the particles can be obtained through calculation according to the magnitude of the output voltage; the induction coils in each group of three coils output a pair of differential voltage signals, the differential voltage signals are very weak, and need to be subjected to preliminary amplification processing, and the first differential amplification module adopts a three-operational amplifier circuit similar to an instrument amplifier for amplification, so that the accuracy of the amplified weak signals is effectively improved; the amplified target signal is still loaded on a carrier, so that the carrier signal is removed by adopting the phase-sensitive demodulation module, on the other hand, the upper computer controls the DSP control module to send a second PWM signal to the phase-sensitive demodulation module to carry out phase adjustment to obtain the maximum value of the induced voltage, and the frequency of the output carrier signal is doubled, so that a low-pass filtering module is arranged to filter a high-frequency carrier signal and a high-frequency clutter signal; the voltage amplitude obtained after phase demodulation and filtering is still small, so that a super servo amplifier module is arranged, the super servo amplifier module can realize a basic amplification function, and can eliminate direct current offset caused by self factors of an operational amplifier device.

Drawings

FIG. 1 is a functional block diagram of the present invention;

FIG. 2 is a schematic diagram of the circuit of the present invention;

FIG. 3 is a partial circuit block diagram of the present invention;

FIG. 4 is a circuit configuration diagram of a first differential amplifier module according to an embodiment;

fig. 5 is a circuit configuration diagram of a first phase sensitive demodulation block in the embodiment;

FIG. 6 is a circuit configuration diagram of a first low-pass filter module in the embodiment;

FIG. 7 is a circuit configuration diagram of a first super servo amplifier module in an embodiment;

FIG. 8 is a circuit configuration diagram of an AD sampling module in the embodiment;

FIG. 9 is a circuit configuration diagram of a DSP control block in the embodiment;

fig. 10 is a circuit configuration diagram of a sensor driving module in the embodiment.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.

The double-coil group lubricating oil crumb on-line monitoring system comprises a power module 1, a sensor module, a signal demodulation module and an upper computer 2, wherein the power module 1 is provided with a first positive voltage output end, a negative voltage output end, a second positive voltage output end and a third positive voltage output end, the output voltage of the first positive voltage output end of the power module is 15V, the output voltage of the negative voltage output end of the power module is-15V, the output voltage of the second positive voltage output end of the power module is 5V, the output voltage of the third positive voltage output end of the power module is 3.3V, the sensor module comprises a sensor driving module 31, a first excitation module 32, a first induction module 33, a second excitation module 34 and a second induction module 35, the signal demodulation module comprises a first differential amplification module 41 and a first sensitive phase demodulation module 42, and the signal demodulation module comprises a first differential amplification module 41 and a first sensitive phase demodulation module 35, A first low-pass filtering module 43, a first super servo amplifier module 44, a second differential amplifying module 51, a second phase-sensitive demodulation module 52, a second low-pass filtering module 53, a second super servo amplifier module 54, an AD sampling module 6 and a DSP control module 7,

the first excitation module 32 comprises a first coil L1, a second coil L2 and a first capacitor C1, the first induction module 33 comprises a third coil L3 and a second capacitor C2, the second excitation module 34 comprises a fourth coil L4, a fifth coil L5 and a third capacitor C3, the second induction module 35 comprises a sixth coil L6 and a fourth capacitor C4, the second coil L2, the third coil L3, the first coil L1, the fifth coil L5, the sixth coil L6 and the fourth coil L4 are sequentially wound outside the oil pipe at intervals from front to back,

the DSP control module 7 sends a first PWM signal to the input terminal of the sensor driving module 31 through the first PWM signal output terminal, the excitation signal output terminal of the sensor driving module 31, one end of the first capacitor C1, one end of the third capacitor C3, one end of the first coil L1, and one end of the fourth coil L4 are connected, the other end of the first coil L1 is connected with one end of the second coil L2, the other end of the fourth coil L4 is connected with one end of the fifth coil L5, the other end of the first capacitor C1, the other end of the third capacitor C3, the other end of the second coil L2, the other end of the fifth coil L5, and the first positive voltage output terminal of the power module 1,

one end of the third coil L3, one end of the second capacitor C2 and the first input end of the first differential amplification module 41 are connected, the other end of the third coil L3, the other end of the second capacitor C2 and the second input end of the first differential amplification module 41 are connected, the output end of the first differential amplification module 41 is connected with the first signal input end of the first phase-sensitive demodulation module 42, the DSP control module 7 sends the second PWM signal to the second signal input end of the first phase-sensitive demodulation module 42 through the second PWM signal output end, the output end of the first phase-sensitive demodulation module 42 is connected with the input end of the first low-pass filter module 43, the output end of the first low-pass filter module 43 is connected with the input end of the first super servo amplifier module 44, the output end of the first super servo amplifier module 44 is connected with the first input end of the AD sampling module 6,

one end of a sixth coil L6, one end of a fourth capacitor C4 and a first input end of a second differential amplification module 51 are connected, the other end of the sixth coil L6, the other end of the fourth capacitor C4 and a second input end of the second differential amplification module 51 are connected, an output end of the second differential amplification module 51 is connected with a first signal input end of a second phase-sensitive demodulation module 52, the DSP control module 7 sends a second PWM signal to a second signal input end of the second phase-sensitive demodulation module 52 through a second PWM signal output end, an output end of the second phase-sensitive demodulation module 52 is connected with an input end of a second low-pass filter module 53, an output end of the second low-pass filter module 53 is connected with an input end of a second super-servo amplifier module 54, an output end of the second super-servo amplifier module 54 is connected with a second input end of an AD sampling module 6, an AD sampling signal output end of the AD sampling module 6 is correspondingly connected with an AD sampling signal input end of the DSP control module 7, the DSP control module 7 is connected with the upper computer 2 through a communication module 8;

the second differential amplification module 51 has the same structure as the first differential amplification module 41, the first differential amplification module 41 includes a first operational amplifier U1, a second operational amplifier U2, a third operational amplifier U3, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a fifth capacitor C5 and a sixth capacitor C6, one end of the first resistor R1 is connected with one end of the second capacitor C2, one end of the second resistor R2 is connected with the other end of the second capacitor C2, the other end of the first resistor R2, the positive input end of the first operational amplifier U2 and one end of the fifth capacitor C2 are connected, the other end of the second resistor R2, the other end of the fifth capacitor R2, the negative input end of the operational amplifier U2 and the negative input end of the operational amplifier U2, One end of a fourth resistor R4 and one end of a fifth resistor R5 are connected, the other end of a fifth resistor R5 is connected with one end of a sixth resistor R6, the other end of the sixth resistor R6, one end of a seventh resistor R7 and a negative input end of a second operational amplifier U2 are connected, the other end of the fourth resistor R4, an output end of the first operational amplifier U1 and one end of a third resistor R3 are connected, the other end of the seventh resistor R7, an output end of the second operational amplifier U2 and one end of an eighth resistor R8 are connected, the other end of the third resistor R3, one end of a ninth resistor R9, one end of an eleventh resistor R11, one end of a sixth capacitor C6 and a negative input end of the third operational amplifier U3 are connected, the other end of the ninth resistor R9 and one end of a tenth resistor R10 are all grounded, the other end of the eighth resistor R8, the other end of the tenth resistor R10 and the positive input end of the third operational amplifier U3 are connected with the first end of the sixth capacitor C6, and the other end of, The other end of the eleventh resistor R11, the other end of the third operational amplifier U3 and the first signal input end of the first phase-sensitive demodulation module 42 are connected;

the first phase-sensitive demodulation module 42 and the second phase-sensitive demodulation module 52 have the same structure, the first phase-sensitive demodulation module 42 includes a phase-locked amplifier U4, a twelfth resistor R12, and a thirteenth resistor R13, the model of the first phase-sensitive demodulation module 42 is AD630AR, one end of the twelfth resistor R12 is connected to the output terminal of the first differential amplification module 41, the other end of the twelfth resistor R12, the 1 st pin of the phase-locked amplifier U4, and the 16 th pin of the phase-locked amplifier U4, the 8 th pin of the phase-locked amplifier U4 is connected to the negative voltage output terminal of the power module 1, the 9 th pin, the 14 th pin, and the 17 th pin of the phase-locked amplifier U4 are all grounded, the 10 th pin of the phase-locked amplifier U4 is connected to the second PWM signal output terminal of the DSP control module 7, the 11 th pin of the phase-locked amplifier U4 is connected to the first positive voltage output terminal of the power module 1, the 13 th pin of the, the other end of the thirteenth resistor R13 is connected to the input end of the first low-pass filter module 43, and the 15 th pin, the 19 th pin, and the 20 th pin of the lock-in amplifier U4 are connected;

the first low-pass filter module 43 and the second low-pass filter module 53 have the same structure, the first low-pass filter module 43 includes a fourteenth resistor R14, a fifteenth resistor R15, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9 and a fourth operational amplifier U5, one end of the fourteenth resistor R14 is connected to the output end of the first phase-sensitive demodulation module 42, the other end of the fourteenth resistor R14 and one end of the fifteenth resistor R15, one end of a seventh capacitor C7 is connected with one end of an eighth capacitor C8, the other end of the seventh capacitor C7, the other end of the eighth capacitor C8, the negative input end of a fourth operational amplifier U5, the output end of the fourth operational amplifier U5 and the input end of the first super servo amplifier module 44 are connected, the other end of a fifteenth resistor R15, one end of a ninth capacitor C9 and the positive input end of the fourth operational amplifier U5 are connected, and the other end of the ninth capacitor C9 is grounded;

the first super servo amplifier module 44 and the second super servo amplifier module 54 have the same structure, the first super servo amplifier module 44 includes a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a tenth capacitor C10, an eleventh capacitor C11, a twelfth capacitor C12, a fifth operational amplifier U6 and a sixth operational amplifier U7, one end of the sixteenth resistor R16 is connected to the output end of the first low-pass filter module 43, the other end of the sixteenth resistor R16, one end of the seventeenth resistor R17, one end of the tenth capacitor C10 and the negative input end of the fifth operational amplifier U6 are connected, the other end of the seventeenth resistor R17, the other end of the tenth capacitor C10, one end of the nineteenth resistor R19, the output end of the fifth operational amplifier U6 and the first input end of the AD sampling module AD6 are connected to the first low-pass filter module 43, a positive input end of a fifth operational amplifier U6 is connected with one end of an eighteenth resistor R18, the other end of an eighteenth resistor R18, one end of an eleventh capacitor C11 and an output end of a sixth operational amplifier U7 are connected, the other end of an eleventh capacitor C11, one end of a twentieth resistor R20 and a negative input end of a sixth operational amplifier U7 are connected, a positive input end of the sixth operational amplifier U7, one end of a twenty-second resistor R22 and one end of a twelfth capacitor C12 are connected, the other end of a nineteenth resistor R19, the other end of a twentieth resistor R20 and one end of a twenty-first resistor R21 are connected, and the other end of the twenty-first resistor R21, the other end of the twenty-second resistor R22 and the other end of the twelfth capacitor C12 are all grounded;

the AD sampling module 6 comprises an AD conversion chip U8 with a model number of AD7890, a thirteenth capacitor C13, a fourteenth capacitor C14, a fifteenth capacitor C15, a sixteenth capacitor C16, an electrolytic capacitor CE, and a twenty-third resistor R23, the DSP control module 7 comprises a DSP chip U9 with a model number of TMS320F28335, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a twenty-eighth resistor R28, a twenty-ninth resistor R29, a thirty-fourth resistor R30, a thirty-eleventh resistor R31, a thirty-second resistor R32, a thirty-third resistor R33, a thirty-fourth resistor R34, a seventeenth capacitor C17, an eighteenth capacitor C9, a first NMOS conversion tube Q1, a pin 1, a pin 3, a pin 15, a pin 21, a pin 22, a pin, a thirteenth capacitor C8623, a positive voltage conversion module terminal of the AD conversion chip U68656 and a positive voltage output terminal of the AD conversion chip U8 and a positive voltage conversion module 8653, the other end of the thirteenth capacitor C13 is grounded, the 4 th pin of the AD conversion chip U8 is connected to one end of a fourteenth capacitor C14, the other end of the fourteenth capacitor C14 is grounded, the 5 th pin of the AD conversion chip U8 is connected to one end of a twenty-seventh resistor R27, the 6 th pin of the AD conversion chip U8 is connected to one end of a twenty-sixth resistor R26, the 7 th pin of the AD conversion chip U8 is connected to one end of a thirty-second resistor R32, the 8 th and 9 th pins of the AD conversion chip U8 are connected to one end of a thirty-third resistor R33, the 10 th pin of the AD conversion chip U8 is connected to one end of a thirty-fourth resistor R30, the 11 th pin of the AD conversion chip U8 is connected to one end of a twenty-eighth resistor R28, the 12 th pin of the AD conversion chip U8, one end of the twenty-third resistor R23, one end of a fifteenth capacitor C15 and the anode of an electrolytic capacitor CE are connected to the twenty-third positive voltage output terminal of the twenty-third power supply R23, the other end of the fifteenth capacitor C15 and the negative electrode of the electrolytic capacitor CE are respectively grounded, the 13 th pin of the AD conversion chip U8 is connected with the 14 th pin, the 19 th pin of the AD conversion chip U8 is connected with the output end of the second super servo amplifier module 54, the 20 th pin of the AD conversion chip U8 is connected with the output end of the first super servo amplifier module 44, the 24 th pin of the AD conversion chip U8 is connected with one end of a sixteenth capacitor C16, and the other end of the sixteenth capacitor C16 is grounded;

a 5 th pin of the DSP chip U9 is connected to one end of a twenty-fourth resistor R24, the other end of the twenty-fourth resistor R24 is connected to an input terminal of the sensor driving module 31, a 7 th pin of the DSP chip U9 is connected to one end of a twenty-fifth resistor R25, the other end of the twenty-fifth resistor R25 is connected to a 10 th pin of the lock-in amplifier U4, a 13 th pin of the DSP chip U9 is connected to the other end of a twenty-sixth resistor R26, a 16 th pin of the DSP chip U9 is connected to the other end of a twenty-seventh resistor R27, a 21 st pin of the DSP chip U9 is connected to the other end of a twenty-eighth resistor R28, a 24 th pin of the DSP chip U9, one end of a twenty-ninth resistor R29 and a drain of the first NMOS transistor Q1, the other end of the twenty-ninth resistor R29 is connected to a third positive voltage output terminal of the power module 1, a source of the first NMOS transistor Q1 is grounded, a gate of the first NMOS transistor Q1, one end of the thirty-third NMOS transistor R30 and an, the other end of the thirty-first resistor R31 is grounded, the 25 th pin of the DSP chip U9 is connected with the other end of the thirty-second resistor R32, the 26 th pin of the DSP chip U9 is connected with the other end of the thirty-third resistor R33, the 55 th pin of the DSP chip U9 is connected with one end of the seventeenth capacitor C17, the 56 th pin of the DSP chip U9 is connected with one end of the eighteenth capacitor C18, the 57 th pin of the DSP chip U9 is connected with one end of the thirty-fourth resistor R34, the 43 th pin of the DSP chip U9, the 54 th pin, the other end of the seventeenth capacitor C17, the other end of the eighteenth capacitor C18 and the other end of the thirty-fourth resistor R34 are all grounded, the 2 nd pin of the DSP chip U9 is used as a transmission output port connected with the communication module 8, and the 141 th pin of the DSP chip U9 is used as a transmission input port connected;

the sensor driving module 31 includes a thirty-fifth resistor R35, a thirty-sixth resistor R36, a thirty-seventh resistor R37, and a second NMOS transistor Q2, wherein one end of the thirty-fifth resistor R35 is connected to the first PWM signal output terminal of the DSP control module 7, the other end of the thirty-fifth resistor R35, one end of the thirty-sixth resistor R36, and the gate of the second NMOS transistor Q2 are connected, the other end of the thirty-sixth resistor R36 and the drain of the second NMOS transistor Q2 are both grounded, the source of the second NMOS transistor Q2 is connected to one end of the thirty-seventh resistor R37, and the other end of the thirty-seventh resistor R37 is connected to one end of the first capacitor C1.