CN210033794U - Signal conditioning device for measuring vibration of nuclear power station main pump - Google Patents
Signal conditioning device for measuring vibration of nuclear power station main pump Download PDFInfo
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- CN210033794U CN210033794U CN201920372994.8U CN201920372994U CN210033794U CN 210033794 U CN210033794 U CN 210033794U CN 201920372994 U CN201920372994 U CN 201920372994U CN 210033794 U CN210033794 U CN 210033794U
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Abstract
The utility model provides a signal conditioning device for measuring nuclear power station main pump vibration, include: vibration sensor and respectively with vibration sensor is connected: an excitation module for providing an excitation signal as a carrier to the vibration sensor; the detection signal transmission module comprises a filtering module, an integrating module, a detecting module and an output module which are connected in sequence; and a sensor fault detection module. The application relates to a circuit structure of a signal conditioning device for measuring the vibration of a nuclear power station main pump, which can realize the detection of the vibration of the nuclear power station main pump. And because the sensor fault detection module is arranged, the fault monitoring of the measuring sensor can be realized.
Description
Technical Field
The utility model relates to a nuclear power monitoring technology field, especially a measure signal conditioning device of nuclear power station main pump vibration.
Background
The nuclear main pump is a pump in a nuclear island primary circuit system for driving coolant to circulate in a reactor coolant system. The main pump is positioned at the heart of the nuclear island and used for pumping hot water into the evaporator to convert heat energy, and is the key for controlling water circulation in nuclear power operation. Measuring the vibration of the main pump has important engineering significance for judging whether the main pump can safely operate for a long time. The prior art with the application number of CN200920148391.6 discloses a portable vibration measurement analyzer, which is not suitable for the nuclear power field, and particularly does not relate to the monitoring technology of a measurement sensor. The above techniques have been monopolized abroad.
SUMMERY OF THE UTILITY MODEL
A primary object of the utility model is to provide a signal conditioning device for measuring nuclear power station main pump vibration, include:
the vibration sensor is used for detecting and measuring the vibration of the main pump of the nuclear power station and outputting the vibration in the form of a carrier modulation signal;
and connected with the vibration sensor respectively:
an excitation module for providing an excitation signal as a carrier to the vibration sensor;
the detection signal transmission module is used for filtering and analyzing the carrier modulation signal output by the vibration sensor so as to output current and/or voltage signals in linear relation with the vibration;
the detection signal transmission module comprises a filtering module, an integrating module, a detecting module and an output module which are connected in sequence;
and the sensor fault detection module is used for detecting the working fault condition of the vibration sensor.
By last, this application relates to a nuclear power station main pump vibration's signal conditioning equipment's circuit structure, can realize the detection to nuclear power station main pump vibration. And because the sensor fault detection module is arranged, the fault monitoring of the measuring sensor can be realized.
The filtering module comprises a first RC filtering circuit, a second RC filtering circuit, a first amplifier and a follower which are connected in sequence.
The integration module comprises a second amplifier and a third amplifier which are connected in sequence;
the inverting input end of the second amplifier is connected with the output end of the filtering module, the output end of the second amplifier is connected with the inverting input end of the third amplifier after being connected with the first potentiometer in series, the inverting input end of the second amplifier is also connected with the output end of the second amplifier, and an RC series circuit is connected between the inverting input end of the second amplifier and the output end of the second amplifier;
the inverting input end of the third amplifier is also connected with the second potentiometer and the output end of the third amplifier;
the non-inverting input ends of the second amplifier and the third amplifier are both grounded.
Therefore, the integration module converts the carrier modulation signal processed by the filtering module into a voltage signal through integration operation and outputs the voltage signal.
The detection module comprises a chip with the model number of AD736, a pin 2 of the chip is connected to the output end of the integration module, a pin 3 of the chip is connected with the third potentiometer, a pin 6 of the chip is connected with the inverting input end of the fourth amplifier, the positive phase input end of the fourth amplifier is grounded, and the positive phase input end of the fourth amplifier is also connected with the fourth potentiometer and then connected with the output end of the fourth amplifier.
The detection module demodulates the filtered and integrated voltage signal into an effective signal (the effective signal is a corresponding vibration signal), and converts the effective signal into direct current.
Wherein the output module comprises a voltage output module and/or a current output module.
The voltage output module comprises an RC filter circuit, a follower circuit and an anti-static circuit which are sequentially connected, and 0-10V voltage is output; and
the RC filter circuit, the follower gain adjusting circuit and the anti-static circuit are connected in sequence, and 0-100mV voltage is output.
Wherein, the current output module comprises a fifth amplifier, the two input ends of the reverse phase and the positive phase are respectively connected with a fifth potentiometer and a sixth potentiometer, the output end is connected with the base electrode of an NPN type triode, the collector electrode of the NPN type triode is connected with +15V power supply, the emitter electrode is connected with a first resistor,
one end of the sixth potentiometer is connected to the output end of the detection module through the seventh potentiometer, the other end of the sixth potentiometer is connected to the first resistor, and the common connection end of the sixth potentiometer and the first resistor serves as the output end of the current output module to output 0-20mA current.
The sensor fault detection module comprises an operational amplification circuit, a signal processing module and a signal processing module, wherein the operational amplification circuit is used for filtering and amplifying a carrier modulation signal output by the vibration sensor;
the first window comparison circuit and the second window comparison circuit are respectively connected with the operational amplification circuit and are used for judging whether the carrier modulation signal is in a preset range of the window comparison circuit, if so, a negative voltage is output, and otherwise, a positive voltage is output;
the LED driving circuit controls the on and off of the LED lamp strip driven by the LED driving circuit based on the voltage output by the first window comparison circuit and the second window comparison circuit.
Therefore, when the fault detection module judges that the carrier modulation signal output by the sensor exceeds the preset range, an alarm can be output, and therefore the working fault condition of the sensor is early warned.
In addition, the protection module is connected with the vibration sensor and used for reducing the interference of the external to the carrier modulation signal output by the vibration sensor.
The protection module comprises an active low-pass filter, a positive phase input end is connected with the output end of the vibration sensor, and a negative phase input end is connected with the output end of the vibration sensor;
the two power supply ends are respectively connected with +/-15V and-15V direct-current voltages;
the positive phase input end is also connected with a positive power supply end after being connected with a second positive diode in series; the positive phase input end is also connected with a second reverse diode in series and then connected with a negative power supply end;
and a voltage dependent resistor and a capacitor are respectively connected in parallel between the output end and the-15V direct-current voltage.
Therefore, the influence on the sensor signal is reduced by matching the piezoresistor VDR2 and the capacitor through the low-pass filter.
Drawings
FIG. 1 is a schematic view of a configuration of a vibration sensor;
FIG. 2 is a schematic circuit structure diagram of a signal conditioning device for measuring the vibration of a main pump of a nuclear power station;
FIG. 3 is a circuit schematic of the excitation module;
FIG. 4 is a schematic diagram of a circuit structure of the detection signal transmission module;
FIG. 5 is a circuit schematic of a filter module;
FIG. 6 is a circuit schematic of an integration module;
FIG. 7 is a schematic circuit diagram of a detector module;
FIG. 8 is a circuit schematic of the voltage output module;
FIG. 9 is a circuit schematic of the current output module;
FIG. 10 is a circuit schematic of a protection module;
FIG. 11 is a circuit schematic of a sensor fault detection module.
Detailed Description
The signal conditioning device for measuring the vibration of the main pump of the nuclear power station according to the present invention will be described in detail with reference to fig. 1 to 11.
The front end of the device is a vibration sensor for detecting the main pump of the nuclear power station as shown in fig. 1, and the vibration sensor comprises a magnetic conduction shell 102, wherein a framework 103 and a movable armature 101 movably fixed on the framework 103 are arranged in the magnetic conduction shell 102. In addition, a primary coil 104 having a turn number W1, and two measuring coils 105 and 106 having turn numbers W2a and W2b, respectively, are fixed to the bobbin 103. The primary coil 104 is energized with an excitation signal of about 2KHz and 20mA as a carrier and the vibration signal as a modulation signal. The two measuring coils 105, 106 generate induced electromotive forces E2a and E2 b. When the movable armature 101 is in the equilibrium position, U-E2 a-E2 b-0, the vibration sensor output is 0.
When the armature is biased to the unbalanced position, U ≠ E2a-E2b ≠ 0, which is a dc voltage of 0-10V with a voltage proportional to the vibration amplitude, and is output as a vibration signal of the vibration sensor in the form of a carrier modulation signal, i.e., corresponding to the vibration signal input shown in fig. 5, which follows.
Fig. 2 is a schematic circuit structure diagram of the signal conditioning device for measuring the vibration of the main pump of the nuclear power plant according to the present application, which includes an excitation module 201, a detection signal transmission module 202, a protection module 203, and a fault detection module 204, which are respectively connected to the vibration sensor, and the following details are described one by one:
the excitation module 201 is configured to provide an excitation signal with a certain frequency as a carrier to the vibration sensor. As shown in fig. 3, which is a schematic circuit diagram of the driver module 201, the driver module 201 according to the present invention employs a circuit composed of a transistor T5 and a current limiting resistor R18. The resistance of the current limiting resistor R18 is 15K, and when the voltage across the resistor R18 is greater than 0.7V, and the excitation current corresponding to the excitation module 201 is greater than 0.46mA, the transistor T5 is turned off. Thereby ensuring that the current output by the excitation module 201 does not exceed 0.46 mA.
The detection signal transmission module 202 is configured to perform filtering, amplification, detection and other processing on the carrier modulation signal output by the vibration sensor, so as to obtain vibration data corresponding to the nuclear power plant main pump. As shown in fig. 4, the detection signal transmission module 202 includes a filtering module 2021, an integrating module 2022, a detecting module 2023, and an output module 2024, which are connected in sequence.
As shown in fig. 5, the core circuit of the filtering module 2021 includes a first RC filtering circuit, a second RC filtering circuit, an amplifier IC1:1 and a follower IC1:2 connected in sequence. The first RC filter circuit includes a capacitor C12 and a resistor R11 connected in series. The second RC filter circuit comprises a resistor R2 and a capacitor C13 which are sequentially connected in series. One end of the resistor R2 is connected to the common connection end of the capacitor C12 and the resistor R11, and the other end is connected to the capacitor C13. The two-way RC filter circuit allows signals between 0.2Hz and 16Khz to pass through. The positive and negative input terminals of the amplifier IC1:1 are respectively connected to the two ends of the capacitor C13, the output terminal is connected to the positive input terminal of the follower IC1:2, and the output terminal is connected to the negative input terminal of the amplifier IC1:1 after being connected to the resistor R4 in series. The follower IC1:2 has its inverting input connected to its output as the output of the filtering module 2021 (shown as "output A" in FIG. 5). The output end of the follower IC1:2 is also connected with the non-inverting input end of the follower IC1:2 after being connected with a capacitor C15 in series, and the non-inverting input end of the follower IC1:2 is connected with the ground after being connected with a capacitor C17 in series. The amplifier IC1:1 and the follower IC1:2 form an active low pass filter that further filters the signal.
The integration module 2022 converts the carrier modulation signal processed by the filtering module 2021 into a voltage signal by an integration operation. As shown in fig. 6, comprises an amplifier IC1:4 and an ac amplifier IC2:1 connected in sequence. The output terminal ("output a" in fig. 6) of the follower IC1:2 in the filter module 2021 is connected in series with a resistor R19 to the inverting input terminal of the amplifier IC1:4, and the inverting input terminal is connected in series with a resistor R20 to the output terminal of the amplifier IC1: 4. In addition, a resistor R21 and a capacitor C22 are connected in parallel between the inverting input terminal and the output terminal. The resistor R21 and the capacitor C22 are connected in series. The output terminal of the amplifier IC1:4 is connected in series with the first potentiometer P1 and then to the inverting input terminal of the ac amplifier IC2:1, and the inverting input terminal is also connected in series with a resistor R14 and then to the output terminal of the ac amplifier IC2:1 as the output terminal of the integrating module 2022 (shown as "output B" in fig. 6). The non-inverting input of the AC amplifier IC2:1 is connected to ground. A second potentiometer P2 is also connected between the flow amplifier IC2:1 and the first potentiometer P1. In the circuit, an integrator is formed by the resistor R21, the capacitor C22 and the operational amplifier IC1:4, and integrates the carrier modulation signal output by the filter module 2021.
The detection module 2023 is configured to demodulate an effective signal (i.e., the effective signal corresponds to the vibration signal) from the filtered and integrated voltage signal, and convert the effective signal into a direct current. As shown in fig. 7, the core of detection module 2023 includes a chip with model AD 736. Pin 2 of the chip is connected to the output terminal of the integrating module 2022, pin 3 of the chip is connected to the potentiometer P6, pin 3 of the chip is connected to the inverting output terminal of the amplifier IC3:2, the non-inverting output terminal of the amplifier IC3:2 is grounded, the non-inverting output terminal of the amplifier IC is connected to the potentiometer P7 and then to the output terminal of the IC3:2, and the output terminal is used as the output terminal of the detecting module 2023.
The AD736 has a high impedance input and therefore can be extended in its input range with a simple resistive attenuator. When attenuation is not carried out, the chip can accurately measure the input signal with the crest factor of 1-3 and the maximum root mean square value of 200 mV. In the circuit, a potentiometer P6 is used to adjust the compensation of the effective value. The potentiometer P7 is used to adjust the gain of the effective value to achieve a +10V output at full scale.
The output module 2024 includes a voltage output module and a current output module. As shown in fig. 8, which is a schematic circuit diagram of the voltage output module, the voltage output module includes two paths:
the first path of voltage output module comprises an RC filter circuit, a follower circuit and an anti-static circuit. The RC filter circuit is a circuit consisting of a resistor R33 and a capacitor C27, low-pass filtering processing is carried out on 10V direct current voltage (corresponding to output C in figure 8) output by the detection module 2023, the voltage is output to a voltage follower IC2:3 for impedance conversion, and then the voltage is processed by an anti-static circuit consisting of a voltage dependent resistor MOV2 and a capacitor C4 to finally output 0-10V voltage.
The second path of voltage output module comprises an RC filter circuit, a follower gain adjusting circuit and an anti-static circuit. The RC filter circuit is a circuit consisting of a resistor R34 and a capacitor C28, low-pass filtering processing is carried out on 10V direct-current voltage output by the detection module 2023, the voltage is output to a voltage follower IC2:4 for impedance conversion, then the impedance conversion is carried out through an anti-static circuit consisting of a voltage dependent resistor MOV2 and a capacitor C4, due to the existence of a gain adjusting circuit P4, the amplification factor of the voltage follower IC2:4 can be dynamically adjusted, and therefore the second path of voltage output module finally outputs 0-100mV voltage.
As shown in fig. 9, which is a schematic circuit diagram of the current output module, two input terminals of an opposite phase and a positive phase of the IC8:4 are respectively connected to the potentiometer P11 and the potentiometer P12, an output terminal is connected to a base of an NPN transistor T2, a collector of the NPN transistor T2 is connected to +15V for power supply, and an emitter is connected to the resistor R91. The potentiometer P12 has one end connected to the 10V dc voltage (corresponding to "output C" in fig. 9) output from the detection module 2023 via the potentiometer P10, and the other end connected to the resistor R91. The common connection end of the potentiometer P12 and the resistor R91 is used as the output end of the current output module, namely, the voltage at the two ends of the resistor R91 follows the input 0-10V signal, and the current of 4-20mA is generated at the output end of the current output module. The voltage at the two ends of the resistor R91 follows the input 0-10V signal, and 4-20mA current is generated at the output end of the current output module. A potentiometer P10 is used for adjusting the current gain, and a potentiometer P11 is used for adjusting the bias voltage.
And the protection module 203 is used for reducing the external interference on the output signal of the vibration sensor. As shown in fig. 10, the core device of the present module is an active low pass filter consisting of an amplifier IC5, which cuts off to a frequency of about 16 kHz. The non-inverting input terminal of the vibration sensor is connected to the output terminal of the vibration sensor, and the inverting input terminal of the vibration sensor is connected to the output terminal of the amplifier IC 5. The power supply terminals of the amplifier IC5 are connected to +15V and-15V dc voltages, respectively. The non-inverting input terminal of the amplifier IC5 is further connected to the positive power terminal of the amplifier IC5 after being connected in series to a forward diode D2. The non-inverting input terminal of the amplifier IC5 is connected to the negative power terminal of the amplifier IC5 after being connected in series to a backward diode D2. Between the output of the amplifier IC5 and the-15V dc voltage, a voltage dependent resistor VDR2 and a capacitor are connected in parallel, thereby reducing the effect of the measurement on the sensor signal. Further, an anti-static chip can be used for replacing the piezoresistor VDR2 and the capacitor.
A sensor failure detection module 204 for detecting an operational failure condition of the vibration sensor. As shown in fig. 11, the sensor failure detection module 202 is composed of an operational amplifier circuit IC7:1, a window comparator circuit IC7:2 and an IC7:3, an LED driver circuit IC7:4, and a failure signal output circuit (a transistor T1 and a resistor R76 and a zener diode D11).
The signals output by the vibration sensor are filtered and amplified by an operational amplifier IC7:1, and then input into a window comparator IC7:2 and an IC7:3, and the limit value range is +/-5V. If the signal output by the vibration sensor is within the limit value range after being processed by the operation amplifying circuit IC7:1, the vibration sensor is indicated to have no fault. At this time, the 12-pin output of the LED driving circuit IC7:4 is a negative voltage, the LED is not on, and T1 is turned off, and the output voltage of the sensor fault detection module 202 is limited to +5V due to the clamping action of the zener diode D11(5V zener). On the contrary, if the signal output by the vibration sensor exceeds the limit range after being processed by the operational amplifier circuit IC7:1, the output of pin 12 of the LED driving circuit IC7:4 is at high level, the LED lights up to emit light, T1 is turned on, the +15V power supply is turned on to ground through the resistor R76 and the transistor T1, and the sensor fault outputs 0V.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.
Claims (10)
1. A signal conditioning device for measuring nuclear power station main pump vibration, characterized by comprising:
the vibration sensor is used for detecting and measuring the vibration of the main pump of the nuclear power station and outputting the vibration in the form of a carrier modulation signal;
and connected with the vibration sensor respectively:
an excitation module (201) for providing an excitation signal as a carrier to the vibration sensor;
a detection signal transmission module (202) for filtering and analyzing the carrier modulation signal output by the vibration sensor to output a current and/or voltage signal having a linear relationship with the vibration;
the detection signal transmission module (202) comprises a filtering module (2021), an integrating module (2022), a detecting module (2023) and an output module (2024) which are connected in sequence;
a sensor fault detection module (204) for detecting an operational fault condition of the vibration sensor.
2. The signal conditioning device according to claim 1, characterized in that the filtering module (2021) comprises a first and a second RC filtering circuit, a first amplifier and a follower connected in sequence.
3. The signal conditioning device of claim 1, wherein the integration module (2022) comprises a second and a third amplifier connected in series;
the inverting input end of the second amplifier is connected with the output end of the filtering module (2021), the output end of the second amplifier is connected with the inverting input end of the third amplifier after being connected with the first potentiometer in series, the inverting input end of the second amplifier is also connected with the output end of the second amplifier, and an RC series circuit is connected between the inverting input end of the second amplifier and the output end of the second amplifier;
the inverting input end of the third amplifier is also connected with the second potentiometer and the output end of the third amplifier;
the non-inverting input ends of the second amplifier and the third amplifier are both grounded.
4. The signal conditioning device of claim 1, wherein the wave detection module (2023) comprises a chip with model AD736, pin 2 of the chip is connected to the output terminal of the integration module (2022), pin 3 is connected to the third potentiometer, pin 6 is connected to the inverting input terminal of the fourth amplifier, the non-inverting input terminal of the fourth amplifier is grounded, and the non-inverting input terminal of the fourth amplifier is further connected to the fourth potentiometer and then connected to the output terminal of the fourth amplifier.
5. The signal conditioning device according to claim 1, wherein the output module (2024) comprises a voltage output module and/or a current output module.
6. The signal conditioning device of claim 5, wherein the voltage output module comprises an RC filter circuit, a follower circuit and an anti-static circuit which are connected in sequence, and outputs a voltage of 0-10V; and
the RC filter circuit, the follower gain adjusting circuit and the anti-static circuit are connected in sequence, and 0-100mV voltage is output.
7. The signal conditioning device according to claim 5, wherein the current output module comprises a fifth amplifier, an inverting input end and a non-inverting input end of the fifth amplifier are respectively connected with a fifth potentiometer and a sixth potentiometer, an output end of the fifth amplifier is connected with a base electrode of an NPN type triode, a collector of the NPN type triode is connected with +15V power supply, and an emitter of the NPN type triode is connected with the first resistor;
one end of a sixth potentiometer is connected to the output end of the detection module (2023) through a seventh potentiometer, the other end of the sixth potentiometer is connected to the first resistor, and the common connection end of the sixth potentiometer and the first resistor serves as the output end of the current output module to output 0-20mA current.
8. The signal conditioning device of claim 1, wherein the sensor fault detection module (204) comprises an operational amplifier circuit for filtering and amplifying the carrier modulation signal output by the vibration sensor;
the first window comparison circuit and the second window comparison circuit are respectively connected with the operational amplification circuit and are used for judging whether the carrier modulation signal is in a preset range of the window comparison circuit, if so, a negative voltage is output, and otherwise, a positive voltage is output;
the LED driving circuit controls the on and off of the LED lamp strip driven by the LED driving circuit based on the voltage output by the first window comparison circuit and the second window comparison circuit.
9. The signal conditioning device of claim 1, further comprising a protection module (203) coupled to the vibration sensor for reducing external interference with a carrier modulated signal output by the vibration sensor.
10. The signal conditioning device of claim 9, wherein the protection module (203) comprises an active low-pass filter having a non-inverting input connected to the output of the vibration sensor and an inverting input connected to the output thereof;
the two power supply ends are respectively connected with +/-15V and-15V direct-current voltages;
the positive phase input end is also connected with a positive power supply end after being connected with a second positive diode in series; the positive phase input end is also connected with a second reverse diode in series and then connected with a negative power supply end;
and a voltage dependent resistor and a capacitor are respectively connected in parallel between the output end and the-15V direct-current voltage.
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| CN201920372994.8U CN210033794U (en) | 2019-03-22 | 2019-03-22 | Signal conditioning device for measuring vibration of nuclear power station main pump |
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| CN201920372994.8U CN210033794U (en) | 2019-03-22 | 2019-03-22 | Signal conditioning device for measuring vibration of nuclear power station main pump |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113156341A (en) * | 2021-03-11 | 2021-07-23 | 南京高速齿轮制造有限公司 | Detection circuit and device for vibration sensor of gear box |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113156341A (en) * | 2021-03-11 | 2021-07-23 | 南京高速齿轮制造有限公司 | Detection circuit and device for vibration sensor of gear box |
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