CN107843654B

CN107843654B - In-service electromagnetic ultrasonic transducer integrity detection system

Info

Publication number: CN107843654B
Application number: CN201711228767.XA
Authority: CN
Inventors: 邢燕好; 徐加欣; 张佳; 李佳音; 刘佳欣; 周宇浩; 杨理践; 任飞跃; 刘畅
Original assignee: Shenyang University of Technology
Current assignee: Shenyang University of Technology
Priority date: 2017-11-29
Filing date: 2017-11-29
Publication date: 2023-09-29
Anticipated expiration: 2037-11-29
Also published as: CN107843654A

Abstract

The invention belongs to the field of electromagnetic ultrasonic detection, and relates to a real-time integrity detection system of an electromagnetic ultrasonic transducer. The device comprises an exciting coil working period detection circuit, a switching circuit, an exciting coil non-working period detection circuit, a magnet magnetism detection circuit, a power supply circuit, a host circuit, a key circuit, a fault display circuit and a buzzer alarm circuit. The singlechip is used as a main control chip, data acquisition is performed by using sensors and the like, all the functions are completed by programming software, and the LCD screen displays, so that the design of the in-service electromagnetic ultrasonic transducer integrity detection system is completed.

Description

In-service electromagnetic ultrasonic transducer integrity detection system

Technical Field

The invention belongs to the field of nondestructive detection, relates to a real-time integrity detection system of an electromagnetic ultrasonic transducer, and particularly relates to an in-service electromagnetic ultrasonic transducer integrity detection system.

Background

Electromagnetic ultrasonic transducers (EMATs) are a novel device for generating ultrasonic waves in conductive metals by using electrodynamic methods, and have a very important role in practical detection work. The core of the electromagnetic ultrasonic detection technology is an electromagnetic ultrasonic transducer. The electromagnetic ultrasonic detection technology can be widely applied to measurement of high-temperature and high-pressure pipelines. In the detection process, the electromagnetic ultrasonic transducer works in a high-temperature and high-pressure environment for a long time. The accuracy of the electromagnetic ultrasonic transducer in acquiring data influences the accuracy of electromagnetic ultrasonic detection. The electromagnetic ultrasonic transducer mainly comprises various combinations of a magnet and a coil, the electromagnetic ultrasonic structural integrity plays a decisive role in smooth electromagnetic ultrasonic detection, and the transducer is far away from a working environment in the process of signal processing, so that the transducer is required to be more stable in hardware performance, the transducer always works in a high-temperature and high-pressure environment, a coil short circuit or open circuit condition is easy to occur to an excitation coil under the working environment due to friction impact and the like, and the excitation coil is dangerous when damaged and is in the open circuit or short circuit state for a long time; when the transducer is in a high-temperature detection environment, demagnetization of the permanent magnet in the transducer is easy to occur, so that the transducer is invalid. Based on electromagnetic ultrasonic transduction principle, its exciting coil works in high-voltage pulse state of hundreds of volts. Once the electromagnetic ultrasonic transducer fails, the hundred-volt high-voltage excitation pulse is extremely easy to cause dangerous conditions, the instrument is damaged when the electromagnetic ultrasonic transducer is light, and the personnel is seriously injured. And is therefore necessary for the integrity detection of in-service electromagnetic ultrasonic transducers.

Disclosure of Invention

The invention aims to:

the magnets and coils of the transducer are vulnerable to damage in high temperature and high pressure harsh operating environments, which can be dangerous once damaged. In order to prevent the danger caused by error detection data and structural damage, the energy converter is controlled, the power supply is disconnected after the energy converter is detected to be damaged, other components can be prevented from being damaged, error collection data is prevented, faults can be timely found and corrected, and an in-service electromagnetic ultrasonic energy converter integrity detection system is designed.

The technical scheme is as follows:

an in-service electromagnetic ultrasonic transducer integrity detection system, which is characterized in that: the device comprises an excitation coil working period detection circuit, a switching circuit, an excitation coil non-working period detection circuit, a magnet magnetism detection circuit, a power supply circuit, a host circuit, a key circuit, a fault display circuit and a buzzer alarm circuit;

the host circuit is connected with the exciting coil working period detection circuit, the exciting coil non-working period detection circuit, the magnet magnetism detection circuit, the power supply circuit, the key circuit, the fault display circuit and the buzzer alarm circuit, and receives signals sent by the exciting coil working period detection circuit, the magnet magnetism detection circuit and the key circuit and sends the signals to the fault display circuit and the buzzer alarm circuit; or the host circuit receives signals sent by the detection circuit, the magnet magnetism detection circuit and the key circuit during the non-working period of the exciting coil and sends the signals to the fault display circuit and the buzzer alarm circuit;

the exciting coil working period detection circuit is connected with the exciting coil non-working period detection circuit, the exciting coil working period detection circuit and the exciting coil non-working period detection circuit are also connected with the switching circuit at the same time, and the switching circuit outputs a control signal to the exciting coil working period detection circuit or the switching circuit; the exciting coil detection circuit is formed by the exciting coil working period detection circuit and the switching circuit or the exciting coil non-working period detection circuit and the switching circuit;

the power supply circuit is connected with the exciting coil working period detection circuit, the exciting coil non-working period detection circuit, the magnet magnetism detection circuit, the host circuit and the fault display circuit for supplying power.

The detection circuit reduces the voltage of a high-frequency high-voltage alternating current pulse signal by a transformer L1 during the working period of the exciting coil, 4 1N4007 rectifier diodes form a unidirectional bridge rectifier circuit, a 10 mu F capacitor C4 and a 0.1 mu F capacitor C5 are connected IN parallel behind the rectifier circuit, the two ends of the capacitor C4 and the capacitor C5 are respectively connected IN series with a 1K resistor R8 and a 1K resistor R9 and are connected into a non-inverting input end IN 1-and an inverting input end In1 of an LM358 respectively, and an output end OUT1 of the LM358 is connected IN series with a 10K resistor R11 and then connected with the inverting input end IN 1; the grounding end GND is grounded, and a 10K resistor R10 is connected IN series between the grounding end GND and the IN-phase input end IN1 < + >; the output end OUT1 is connected with a P10 port of the singlechip; the IN-phase input end In2+ is connected with a magnetic detection circuit signal of the magnet, the output end OUT2 is connected with the anti-phase input end IN 2-to form a voltage follower, and the output end OUT2 is connected with a P11 port of the singlechip; the power interface VCC is connected with a power supply, and is connected with a 0.1 mu F capacitor C6 in series and then grounded to filter out high-frequency interference; one end of the bridge type is connected with a 1K resistor R16 in series and then connected with a power supply.

The detection circuit is used for measuring voltages at two ends of the exciting coil by externally applying periodic direct current voltage during the non-working period of the exciting coil, a differential proportion operation circuit is formed by utilizing the integrated operational amplifier LM358, the resistance value 1K of the detection circuit during the non-working period of the exciting coil is connected with the sliding end of the sliding rheostat R17 of the serial switching circuit of the resistor R19, and the other end of the resistor R19 is connected with the IN-phase input end In1+ of the LM 358; the LM358 grounding end GND is grounded and simultaneously connected IN series with a resistor R20 with a resistance value of 10K, and the other end of the resistor R20 is connected with the IN-phase input end IN1+; the inverting input end IN 1-is connected IN series with a resistor R18 with the resistance value of 1K, the other end of the resistor R18 is grounded, the output end OUT1 is connected IN series with a resistor R21 with the resistance value of 10K, and the other end of the resistor R21 is connected into the inverting input end IN1-; the output end OUT1 is also connected with a P10 port of the singlechip; the LM358 power interface VCC is connected with a power supply, and is connected with a 0.1 mu F capacitor C7 in series and then grounded to filter out high-frequency interference.

The switching circuit is composed of electromagnetic relays, and the detection circuit is switched according to the working period of the transducer; one end of the electromagnetic relay is connected with a power supply, and the other end of the electromagnetic relay is connected with a 2N3904 triode Q2 and a 10K resistor R15 in series and then connected with a P12 interface of the singlechip; the pin 4 of the connector Header2 is internally connected with the pin 5, one end of the fixed end of the sliding rheostat R17 is connected with the sliding end, meanwhile, the pin 4 of the connector Header2 is connected with the resistor R19 in the detection circuit in the period that the exciting coil is not in operation, and the other end of the sliding rheostat R17 is connected with the switch K1 knife 3 after being connected with a power supply; the switch K1 knife 1 is connected with the connector 2 pin 5; the switch K1 knife 2 is connected with the transformer L1, and the other end of the transformer L1 is connected with the connector 2 pin 4.

The magnetic field detection circuit is used for accurately measuring the magnetic field of the magnet, and the Hall sensor 3144 module is used for measuring the magnetic field of the magnet; the power end 4 of the Hall element 3144 is connected with a power supply, the grounding end 6 is grounded, and the output end 5 is connected with the non-inverting input end 8 of the single-limit comparator; the power end 9 of the single-limit comparator is connected with a power supply and is connected with a resistor R4 with the resistance of 10K in series, the other end of the resistor R4 is connected with a light-emitting diode (LED) 1, the other end of the light-emitting diode (LED) 1 is connected with the output end 11 of the single-limit comparator, the output end 11 is also connected with a capacitor C1 with the capacitance of 0.1 mu F, and the other end of the capacitor C1 is grounded; the grounding end 10 of the single-limit comparator is grounded, the inverting input end 7 is connected with the sliding end of the sliding rheostat R3, one end of the fixed end of the sliding rheostat R3 is connected with a power supply, and the other end is grounded; the output end 11 of the single-limit comparator is also connected with the connector Header3 pin 2, the connector Header3 pin 2 is connected with the LM358 IN-phase input end In2+ IN the detection circuit during the working period of the exciting coil, the connector Header3 pin 1 is connected with a power supply, and the Header3 pin 3 is grounded.

The buzzer alarm circuit selects a PNP type triode Q3 as a switch for conducting the buzzer LS1, namely, the base electrode end of the PNP type triode Q3 is connected in series with a resistor R22 with the resistance value of 4.7K, the other end of the resistor R22 is connected with the P32 port of the singlechip, the emitter of the triode Q3 is connected with the buzzer LS1, the other end of the buzzer LS1 is connected with a power supply, and the collector of the triode is grounded.

The fault display circuit displays the detected fault type by adopting an LCD1602 liquid crystal screen; wherein the pin V0 is the third pin connected with the sliding end of the sliding rheostat R2, one end of the fixed end of the sliding rheostat R2 is connected with a power supply, and the other end is grounded.

The host circuit main controller adopts a singlechip STC12C5A60S2 to collect voltage, and the singlechip carries out analog-to-digital conversion on an analog signal output by the coil detection circuit by utilizing self-contained A/D in the singlechip; the connection of the singlechip circuit accords with the connection method of the singlechip minimum system circuit, namely the grounding of the singlechip grounding end GND; the power end VCC is connected with a power supply and connected with a capacitor C2 in series, and the other end of the capacitor C2 is grounded; the pin P10 is connected with the output end OUT1 of the operational amplifier LM358 of the detection circuit during the working period of the exciting coil and the output end OUT1 of the operational amplifier LM358 of the detection circuit during the non-working period of the exciting coil, and performs analog-digital conversion on the output signal of the detection circuit of the exciting coil; the pin P11 is connected with the output end OUT2 of the detection circuit operational amplifier LM358 during the working period of the exciting coil, and the receiving signal is subjected to analog-digital conversion; the 3 pin P12 is connected with the switching circuit resistor R15 to control the electromagnetic relay to work; the reset pin 9REST is connected with a capacitor C3 with a capacitance value of 1 mu F, the reset pin 9REST is also connected with a resistor R1 with a resistance value of 10K, the other end of the resistor R1 is grounded, the other end of the capacitor C3 is connected with a power supply VCC, and the reset pin 9REST and the capacitor C3 form a reset circuit; the 12 pin P32 is connected with a buzzer alarm circuit; the 18-pin XTAL2 is connected with an external crystal oscillator Y1 and is connected with a capacitor C13 with the capacitance value of 30pF, and the other end of the capacitor C13 is grounded; the other end of the external crystal oscillator Y1 is connected with the 19-pin XTAL 1; the pin 19 is connected with a capacitor C14 with a capacitance of 30pF, and the other end of the capacitor C14 is grounded; the 18-pin XTAL2, the 19-pin XTAL1, the crystal oscillator Y1, the capacitor C13 and the capacitor C14 form an oscillating circuit; the 25 pin P24 is connected with the LED D1 and the resistor R7 with the resistance value of 1K in series and then is connected with a power supply, and the 21 pin P20, the 22 pin P21 and the 23 pin P23 are respectively connected with the double-pole double-throw switch SW-DPST in series;

the KEY circuit mode selection switches KEY MOD, the '-' operation switches KEY and the '+' operation switches KEY ADD are respectively connected in series with a double-pole double-throw switch SW-DPST and then grounded, and the other ends of the switches are correspondingly connected with the 21 pin, the 22 pin and the 23 pin of the singlechip in the host circuit.

After the power supply circuit is powered on, the circuit is powered on, and a capacitor C1 with 100 mu F is connected in series to be grounded to filter high-frequency interference; the power supply is connected with a connector 4 pin 1 and is connected with a capacitor C1 with a capacitance value of 100 mu F, and the other end of the capacitor C1 is grounded; one end of the light emitting diode D4 is connected in series with a resistor R6 with the resistance value of 1K, the other end of the resistor R6 is grounded, and the other end of the light emitting diode D4 is connected with a power supply; pin 1 and pin 2 of connector Header 4 are connected; the pin 3 and the pin 4 are connected and then grounded; and the connector Header 4 leads out wires to supply power for all parts of the system.

The method for detecting the in-service electromagnetic ultrasonic transducer integrity detection system is characterized by comprising the following steps of: the detection method comprises the following steps:

1) Starting a power supply circuit to supply power for the host circuit;

2) The magnet is close to a Hall element of the magnetic detection circuit, the magnetic detection circuit of the magnet outputs a signal, the result is transmitted to a liquid crystal screen of the fault circuit after analog-digital conversion of the singlechip, and if the liquid crystal screen of the fault circuit shows that the magnet is intact, the magnet has no fault; if the liquid crystal screen of the fault circuit displays the magnet fault and the buzzer alarms, the magnet needs to be replaced;

3) The mode selection is carried out through keys of the key circuit, the singlechip is controlled to output potential, the singlechip outputs signals to the switching circuit, the switching circuit triode is controlled to be conducted or blocked through outputting high and low levels, the on-off of the electromagnet of the switching circuit is further controlled, and the state of a knife switch of the switch is changed, so that the detection circuit in the non-working period of the exciting coil or the detection circuit in the working period of the exciting coil is selected, and whether the exciting coil of the electromagnetic ultrasonic transducer is good or not is detected;

4) When the exciting coil does not work, the exciting coil is detected by using a detecting circuit in the non-working period of the exciting coil, a signal is output by the detecting circuit in the non-working period of the exciting coil, the result is transmitted to a liquid crystal screen of a fault circuit after analog-to-digital conversion of the singlechip, and if the liquid crystal screen shows that the exciting coil is good, the exciting coil can work; if the liquid crystal display displays the fault of the exciting coil, the buzzer circuit gives an alarm, and the exciting coil needs to be replaced;

when the exciting coil works, the exciting coil is detected by using a detecting circuit in the working period of the exciting coil, a signal is output by the detecting circuit in the working period of the exciting coil, the result is transmitted to a liquid crystal screen of a fault circuit after analog-to-digital conversion of the singlechip, and if the liquid crystal screen displays that the exciting coil is good, the exciting coil can continue to work; if the liquid crystal display displays the fault of the exciting coil and the buzzer circuit gives an alarm, the exciting coil needs to be replaced.

The advantages and effects:

1. the in-service electromagnetic ultrasonic transducer integrity detection system is designed aiming at the characteristic that the coil and the magnet are damaged when the electromagnetic transducer always works in a high-temperature and high-pressure environment, and the electromagnetic ultrasonic transducer is detected in real time, so that the damage of the transducer is discovered early;

2. detecting magnetism of the magnet of the electromagnetic ultrasonic transducer, finding out whether the magnet is in a good working state in time, avoiding influencing a measurement result due to demagnetization of the magnet, and eliminating casualties and property loss of the transducer caused by incapability of adsorbing a workpiece due to demagnetization of the magnet;

1. when the electromagnetic ultrasonic transducer works, the exciting coil works in a high-voltage pulse state of hundreds of volts, and the detection during the non-working period of the exciting coil can prevent the damage to workpieces and personnel caused by the short circuit and disconnection of the coil due to the applied high voltage at the beginning of the work;

2. the excitation coil is also possible to be short-circuited and open-circuited during the working period of the electromagnetic ultrasonic transducer, and the detection of the excitation coil during the working period can avoid the damage to a workpiece and the casualties caused by the sudden failure of the coil during the working;

3. the integrity of the electromagnetic ultrasonic transducer can be judged by the in-service electromagnetic ultrasonic transducer integrity detection system for detecting the electromagnetic ultrasonic transducer, so that the detection result and the detection precision are improved;

4. after the detection system detects that the transducer is damaged, the power supply is disconnected, so that other components can be prevented from being damaged, errors of collected data are prevented, and faults can be found and corrected in time;

5. the detection system is simple to operate, faults are displayed on the LCD screen, and meanwhile, the buzzer alarm circuit is used for alarming, so that faults can be found in time, the fault reasons are known, and the safety of the electromagnetic ultrasonic transducer, the tested workpiece and staff is protected.

Drawings

FIG. 1 is a schematic diagram of an overall detection system;

FIG. 2 is a diagram of a detection circuit during operation of the excitation coil;

FIG. 3 is a diagram of a detection circuit during non-operation of the excitation coil;

FIG. 4 is a switching circuit diagram;

FIG. 5 is a diagram of a magnetic detection circuit of a magnet;

FIG. 6 is a buzzer alarm circuit diagram;

FIG. 7 is a circuit diagram showing a fault;

FIG. 8 is a circuit diagram of a host;

FIG. 9 is a circuit diagram of a power supply;

FIG. 10 is a key circuit diagram.

The label is as follows: 101: excitation coil during operation detection circuit, 102: switching circuit, 103: excitation coil non-operation period detection circuit, 104: magnet magnetism detection circuit, 105: power supply circuit, 106: host circuitry, 107: key circuit, 108: fault display circuit, 109: and a buzzer alarm circuit.

Detailed Description

As shown in fig. 1, an in-service electromagnetic ultrasonic transducer integrity detection system comprises an excitation coil working period detection circuit 101, a switching circuit 102, an excitation coil non-working period detection circuit 103, a magnet magnetism detection circuit 104, a power supply circuit 105, a host circuit 106, a key circuit 107, a fault display circuit 108 and a buzzer alarm circuit 109;

the host circuit 106 is connected with the exciting coil working period detection circuit 101, the exciting coil non-working period detection circuit 103, the magnet magnetism detection circuit 104, the power supply circuit 105, the key circuit 107, the fault display circuit 108 and the buzzer alarm circuit 109, and the host circuit 106 receives signals sent by the exciting coil working period detection circuit 101, the magnet magnetism detection circuit 104 and the key circuit 107 and sends the signals to the fault display circuit 108 and the buzzer alarm circuit 109; or the host circuit 106 receives signals sent by the exciting coil non-working period detection circuit 103, the magnet magnetism detection circuit 104 and the key circuit 107 and sends the signals to the fault display circuit 108 and the buzzer alarm circuit 109;

the exciting coil working period detection circuit 101 is connected with the exciting coil non-working period detection circuit 103, the exciting coil working period detection circuit 101 and the exciting coil non-working period detection circuit 103 are also connected with the switching circuit 102 at the same time, and the switching circuit 102 outputs a control signal to the exciting coil working period detection circuit 101 or the switching circuit 103; the exciting coil in-operation period detection circuit 101 and the switching circuit 102 or the exciting coil in-non-operation period detection circuit 103 and the switching circuit 102 constitute an exciting coil detection circuit;

the power supply circuit 105 is connected to the exciting coil operation period detection circuit 101, exciting coil non-operation period detection circuit 103, magnet magnetism detection circuit 104, host circuit 106, and fault display circuit 108 for supplying power.

As shown IN fig. 2, the detection circuit 101 is configured to step down the high-frequency and high-voltage ac pulse signal by the transformer L1 during the operation of the exciting coil, 4 1N4007 rectifier diodes form a unidirectional bridge rectifier circuit, a 10 μf capacitor C4 and a 0.1 μf capacitor C5 are connected IN parallel after the rectifier circuit, two ends of the capacitor C4 and the capacitor C5 are respectively connected IN series with a 1K resistor R8 and a 1K resistor R9 respectively and then connected to the IN-phase input terminal IN 1-and the inverting input terminal in1+ of the LM358, and the output terminal OUT1 of the LM358 is connected IN series with a 10K resistor R11 and then connected to the inverting input terminal IN1-; the grounding end GND is grounded, and a 10K resistor R10 is connected IN series between the grounding end GND and the IN-phase input end IN1 < + >; the output end OUT1 is connected with a P10 port of the singlechip; the IN-phase input end In2+ is connected with a magnetic detection circuit signal of the magnet, the output end OUT2 is connected with the anti-phase input end IN 2-to form a voltage follower, the output end OUT2 is connected with a P11 port of the singlechip, and the output signal is connected with an A/D conversion interface of the singlechip to carry OUT analog-to-digital conversion; the power interface VCC is connected with a power supply, and is connected with a 0.1 mu F capacitor C6 in series and then grounded to filter out high-frequency interference; one end of the bridge is connected with a 1K resistor R16 in series and then connected with a power supply, so that the bridge is in a critical conduction state, the signal loss is reduced, and the signal loss ratio is improved.

As shown in fig. 3, the detection circuit 103 measures the voltages at two ends of the exciting coil by applying a periodic dc voltage to the exciting coil during the non-working period, and the differential proportional operation circuit is formed by using the integrated op-amp LM358, wherein the LM358 is a dual op-amp. Has independent power and ground terminals. The dual operational amplifier has two independent dual operational amplifiers with high gain and capable of compensating internal frequency, is suitable for a single power supply with a wide voltage range, is also suitable for a dual power supply working mode, and has uncorrelated current and voltage under normal working conditions. The resistance value 1K resistor R19 of the detection circuit is connected with the sliding end of the sliding rheostat R17 of the series switching circuit during the non-working period of the exciting coil, and the other end of the resistor R19 is connected with the IN-phase input end In1+ of the LM 358; the LM358 grounding end GND is grounded and simultaneously connected IN series with a resistor R20 with a resistance value of 10K, and the other end of the resistor R20 is connected with the IN-phase input end IN1+; the inverting input end IN 1-is connected IN series with a resistor R18 with the resistance value of 1K, the other end of the resistor R18 is grounded, the output end OUT1 is connected IN series with a resistor R21 with the resistance value of 10K, and the other end of the resistor R21 is connected into the inverting input end IN1-; the output end OUT1 is also connected with a P10 port of the singlechip; the LM358 power interface VCC is connected with a power supply, and is connected with a 0.1 mu F capacitor C7 in series and then grounded to filter out high-frequency interference. The variable resistor of the resistor R17 plays a role of a protection circuit, the resistors R18 and R19 are set to be the same in resistance value, the resistors R20 and R21 are set to be the same in resistance value, the voltage at two ends of the exciting coil can be obtained through the differential proportion operation circuit, and the output voltage is directly connected with the I/O port of the singlechip.

As shown in fig. 4, the switching circuit 102 is composed of electromagnetic relays, and switches the detection circuit according to the working period of the transducer; one end of the electromagnetic relay is connected with a power supply, and the other end of the electromagnetic relay is connected with a 2N3904 triode Q2 and a 10K resistor R15 in series and then connected with a P12 interface of the singlechip; the pin 4 of the connector Header2 is internally connected with the pin 5, one end of the fixed end of the sliding rheostat R17 is connected with the sliding end, meanwhile, the pin 4 of the connector Header2 is connected with the resistor R19 in the detection circuit in the period that the exciting coil is not in operation, and the other end of the sliding rheostat R17 is connected with the switch K1 knife 3 after being connected with a power supply; the switch K1 knife 1 is connected with the connector 2 pin 5; the switch K1 knife 2 is connected with the transformer L1, and the other end of the transformer L1 is connected with the connector 2 pin 4; when the P12 port outputs high level, the transistor is conducted, the electromagnetic relay works, and when the switch K1 is connected with the switch blades 1 and 3, the detection circuit works during the period that the excitation coil does not work; when the P12 port outputs low level, the transistor is not conducted, the electromagnetic relay does not work, the switch K1 knife 1 and the switch K2 are connected, and the detection circuit works during the working period of the exciting coil; the high-frequency high-voltage alternating current pulse signal is reduced to a rectifying circuit through a transformer.

As shown in fig. 5, the magnetic field of the magnet is accurately measured by the magnetic field detection circuit 104, and the magnetic field of the magnet is measured by the hall sensor 3144 module; the power end 4 of the Hall element 3144 is connected with a power supply, the grounding end 6 is grounded, and the output end 5 is connected with the non-inverting input end 8 of the single-limit comparator; the power end 9 of the single-limit comparator is connected with a power supply and is connected with a resistor R4 with the resistance of 10K in series, the other end of the resistor R4 is connected with a light-emitting diode (LED) 1, the other end of the light-emitting diode (LED) 1 is connected with the output end 11 of the single-limit comparator, the output end 11 is also connected with a capacitor C1 with the capacitance of 0.1 mu F, and the other end of the capacitor C1 is grounded; the grounding end 10 of the single-limit comparator is grounded, the inverting input end 7 is connected with the sliding end of the sliding rheostat R3, one end of the fixed end of the sliding rheostat R3 is connected with a power supply, and the other end is grounded; the output end 11 of the single-limit comparator is also connected with a connector Header3 pin 2, the connector Header3 pin 2 is connected with an LM358 IN-phase input end In2+ IN a detection circuit during the working period of the exciting coil, the connector Header3 pin 1 is connected with a power supply, and the Header3 pin 3 is grounded; when the Hall element detects a magnetic field, a signal is output, the voltage is output after the signal passes through the single-limit comparator, the circuit where the light-emitting diode LED1 is positioned has no current, the circuit does not work, the LED1 is not lightened, and the signal is output to the IN-phase input end In2+ of the operational amplifier LM358 of the detection circuit during the working period of the exciting coil; when the Hall element does not detect a magnetic field, no signal is output, the output end of the single-limit comparator is negative, the circuit where the light-emitting diode LED1 is positioned is conducted, and the LED1 emits light to play a role in alarming.

As shown in fig. 6, the buzzer alarm circuit 109 selects a PNP type triode Q3 as a switch for conducting the buzzer LS1, that is, a base terminal of the PNP type triode Q3 is connected in series with a resistor R22 with a resistance value of 4.7K, the other end of the resistor R22 is connected with a P32 port of the singlechip, an emitter of the triode Q3 is connected with the buzzer LS1, the other end of the buzzer LS1 is connected with a power supply, a collector of the triode is grounded, when the singlechip gives a low level to an I/O corresponding to the buzzer LS1, a base of the triode Q3 corresponds to a low level, the triode Q3 is saturated and conducted to enable the buzzer LS1 to start working, and when the base of the triode Q3 is high level, the triode Q3 is not conducted, and the buzzer LS1 stops working. The circuit alarms when a short circuit or open circuit of the coil or a demagnetizing condition of the magnet is detected.

As shown in fig. 7, the fault display circuit 108 displays the detected fault type by using an LCD1602 liquid crystal screen; the V0 pin is the third pin and is connected with the sliding end of the sliding rheostat R2, one end of the fixed end of the sliding rheostat R2 is connected with a power supply, and the other end of the fixed end of the sliding rheostat R2 is grounded; the display contrast of the liquid crystal is regulated, and the voltage value is changed by changing the resistance value of the slide rheostat, so that the liquid crystal is displayed in the clearest state.

As shown in fig. 8, the host circuit 106 uses a single-chip microcomputer STC12C5a60S2 to perform voltage acquisition, and the single-chip microcomputer uses a self-contained a/D in the single-chip microcomputer to perform analog-to-digital conversion on the analog signal output by the coil detection circuit; the connection of the singlechip circuit accords with the connection method of the singlechip minimum system circuit, namely the grounding of the singlechip grounding end GND; the power supply end VCC is connected with a power supply and connected with a capacitor C2 in series, and is used for filtering out high-frequency interference, and the other end of the capacitor C2 is grounded; the pin P10 is connected with the output end OUT1 of the operational amplifier LM358 of the detection circuit during the working period of the exciting coil and the output end OUT1 of the operational amplifier LM358 of the detection circuit during the non-working period of the exciting coil, and performs analog-digital conversion on the output signal of the detection circuit of the exciting coil; the pin P11 is connected with the output end OUT2 of the detection circuit operational amplifier LM358 during the working period of the exciting coil, and the receiving signal is subjected to analog-digital conversion; the 3 pin P12 is connected with the switching circuit resistor R15 to control the electromagnetic relay to work; the reset pin 9REST is connected with a capacitor C3 with a capacitance value of 1 mu F, the reset pin 9REST is also connected with a resistor R1 with a resistance value of 10K, the other end of the resistor R1 is grounded, the other end of the capacitor C3 is connected with a power supply VCC, and the reset pin 9REST and the capacitor C3 form a reset circuit; the 12 pin P32 is connected with a buzzer alarm circuit; the 18-pin XTAL2 is connected with an external crystal oscillator Y1 and is connected with a capacitor C13 with the capacitance value of 30pF, and the other end of the capacitor C13 is grounded; the other end of the external crystal oscillator Y1 is connected with the 19-pin XTAL 1; the pin 19 is connected with a capacitor C14 with a capacitance of 30pF, and the other end of the capacitor C14 is grounded; the 18-pin XTAL2, the 19-pin XTAL1, the crystal oscillator Y1, the capacitor C13 and the capacitor C14 form an oscillating circuit; the 25 pin P24 is connected with the LED D1 and the resistor R7 with the resistance value of 1K in series and then is connected with a power supply, and is conducted when in work, and the LED emits light to be used as a power supply indicator lamp; the pins P20, P21 and P23 are respectively connected in series with a double pole double throw switch SW-DPST, and are used as ' mode selection ', ' and ' plus '; the 26-28 pins and the 32-39 pins are connected with a Liquid Crystal Display (LCD) 602 to control a fault display circuit;

as shown in fig. 10, the mode selection switches KEY MOD, the'-' operation switch KEY SUB, and the'++' operation switch KEY ADD of the KEY circuit 107 are respectively connected in series with a double-pole double-throw switch SW-DPST and then grounded, and the other ends of the switches are correspondingly connected to the 21 pin, the 22 pin, and the 23 pin of the single chip microcomputer in the host circuit 106.

As shown in fig. 9, the power circuit 105 is powered after being powered on, and a capacitor C1 with 100 μf is connected in series to ground to filter out high-frequency interference; the power supply is connected with a connector 4 pin 1 and is connected with a capacitor C1 with a capacitance value of 100 mu F, and the other end of the capacitor C1 is grounded; one end of the light emitting diode D4 is connected in series with a resistor R6 with the resistance value of 1K, the other end of the resistor R6 is grounded, and the other end of the light emitting diode D4 is connected with a power supply; pin 1 and pin 2 of connector Header 4 are connected; the pin 3 and the pin 4 are connected and then grounded; the connector Header 4 leads out wires to supply power for each part of the system; when power is supplied, overcurrent is reserved in a circuit where the light-emitting diode D4 is located, and the light-emitting diode D4 works and emits light to serve as a power supply work indicator lamp.

The detection method of the in-service electromagnetic ultrasonic transducer integrity detection system comprises the following steps:

1) Starting a power supply circuit to supply power for the host circuit;

2) The magnet is close to a Hall element of the magnetic detection circuit, a signal is output by the magnetic detection circuit of the magnet, the result is transmitted to an LCD1602 liquid crystal screen of the fault circuit after analog-to-digital conversion of the singlechip, and if the LCD1602 liquid crystal screen of the fault circuit displays that the magnet is perfect, the magnet has no fault; if the LCD1602 liquid crystal screen of the fault circuit displays the magnet fault and the buzzer alarms, the magnet needs to be replaced;

4) When the exciting coil does not work, the exciting coil is detected by using a detecting circuit in the non-working period of the exciting coil, a signal is output by the detecting circuit in the non-working period of the exciting coil, the result is transmitted to an LCD1602 liquid crystal screen of a fault circuit after analog-to-digital conversion of the singlechip, and if the liquid crystal screen displays that the exciting coil is good, the exciting coil can work; if the liquid crystal display displays the fault of the exciting coil, the buzzer circuit gives an alarm, and the exciting coil needs to be replaced;

when the exciting coil works, the exciting coil is detected by using a detecting circuit in the working period of the exciting coil, a signal is output by the detecting circuit in the working period of the exciting coil, the result is transmitted to an LCD1602 liquid crystal screen of a fault circuit after analog-to-digital conversion by a singlechip, and if the liquid crystal screen displays that the exciting coil is good, the exciting coil can continue to work; if the liquid crystal display displays the fault of the exciting coil and the buzzer circuit gives an alarm, the exciting coil needs to be replaced.

The working principle of the invention is as follows:

the design is an in-service electromagnetic ultrasonic transducer integrity detection system, and the electromagnetic ultrasonic transducer integrity is dynamically detected. The system takes an STC12C5A60S2 singlechip with low power consumption and self A/D conversion as a core, carries out real-time integrity detection on each component part of the electromagnetic ultrasonic transducer, and detects that the magnetism of the magnet disappears through a Hall sensor when the magnet is demagnetized; when the coil is short-circuited or short-circuited, the measured voltage is not equal to the normal voltage (the measured value is smaller than the short circuit of the measured voltage coil, and the measured value is zero), the singlechip immediately sends out a control signal to control the electromagnetic ultrasonic transducer to stop working, so that the safety is ensured, and the in-service electromagnetic ultrasonic transducer integrity detection design is realized.

The detection system comprises an excitation coil integrity detection circuit, a magnet magnetism detection circuit, a host circuit, a buzzer alarm circuit and a fault display circuit.

The exciting coil converts an alternating current pulse signal into direct current output by utilizing a rectifying and filtering circuit during the working period, and the circuit not only can output larger current, but also can convert alternating current voltage into smooth direct current voltage. The transformer steps down the high-frequency high-voltage alternating current pulse signal, the bridge circuit formed by 4 1N4007 rectifier diodes is a unidirectional bridge rectifier circuit, and because the output voltage of the rectifier circuit is unidirectional, but still contains larger alternating current components, the pulsating direct current voltage is changed into smooth direct current voltage by a filter circuit after the rectifier circuit, the filter circuit is connected with a capacitor in parallel at the output end of the rectifier circuit to form a capacitor filter circuit, and the circuit utilizes the electrolytic capacitor and utilizes the functions of large capacity and charge and discharge of the capacitor to finally lead the output voltage to be approximate to mild. The exciting coil applies periodic direct current voltage to measure the voltages at two ends of the coil in a non-working period, an integrated operational amplifier LM358 is utilized to form a differential proportion operation circuit, the voltages at two ends of the exciting coil can be obtained through the differential proportion operation circuit, and the output voltage is directly connected with an IO port of the singlechip. Switching of the detection circuit within the transducer duty cycle is achieved using electromagnetic relays.

The magnet magnetism detection circuit measures the magnetic field of the magnet by using a Hall sensor 3144 module, and outputs a switching signal to be sent into the singlechip.

The host circuit uses the singlechip STC12C5A60S2 to collect voltage, and the singlechip carries out analog-to-digital conversion on the analog signal output by the coil detection circuit by utilizing the built-in A/D of the singlechip. And voltage detection is carried out by using an A/D conversion part of the singlechip. The analog-to-digital conversion port of the STC12C5A60S2 singlechip is provided with 10-bit 8-path high-speed analog-to-digital conversion at the P1 port. The A/D conversion of the singlechip is voltage input type, the conversion speed is very fast, and the conversion speed can reach 25 ten thousand times per second. The P1 port after reset is a weak pull-up type I/O port, any bit on the P2 port can be set as an A/D conversion port through software, and other bits which are not used for analog-to-digital conversion can still be used as a common I/O port. The host circuit can realize the functions of all parts by programming the software and burning the software into the singlechip.

The driving circuit of the buzzer alarm circuit comprises three main parts, namely a triode, a buzzer and a current-limiting resistor. The buzzer is a component capable of emitting sound, and the direct current voltage is added to two ends of the active buzzer or the square wave is added to the passive buzzer to emit sound. Because the I/O port of the singlechip defaults to be high level, the PNP type triode is selected to be used as a switch for conducting the buzzer, namely, the base end of the PNP type triode is connected with the I/O port of the singlechip, when the singlechip gives the low level to the I/O corresponding to the buzzer, the base of the triode corresponds to the low level, the triode is conducted in a saturated manner, the buzzer starts to work, and when the base of the triode is high level, the triode is not conducted, and the buzzer stops working.

The fault display circuit displays the detected fault type by adopting an LCD1602 liquid crystal screen.

The foregoing is a detailed description of the invention in connection with the preferred embodiments, and it is not intended to limit the invention to the specific embodiments, but is to be construed as the scope of the invention for simple deduction and substitution without departing from the spirit of the invention.

Claims

1. An in-service electromagnetic ultrasonic transducer integrity detection system, which is characterized in that: the device comprises an excitation coil working period detection circuit, a switching circuit, an excitation coil non-working period detection circuit, a magnet magnetism detection circuit, a power supply circuit, a host circuit, a key circuit, a fault display circuit and a buzzer alarm circuit;

the power supply circuit is connected with the exciting coil working period detection circuit, the exciting coil non-working period detection circuit, the magnet magnetism detection circuit, the host circuit and the fault display circuit for supplying power;

the detection circuit reduces the voltage of a high-frequency high-voltage alternating current pulse signal by a transformer L1 during the working period of the exciting coil, 4 1N4007 rectifier diodes form a unidirectional bridge rectifier circuit, a 10 mu F capacitor C4 and a 0.1 mu F capacitor C5 are connected IN parallel behind the rectifier circuit, the two ends of the capacitor C4 and the capacitor C5 are respectively connected IN series with a 1K resistor R8 and a 1K resistor R9 and are connected into a non-inverting input end IN 1-and an inverting input end In1 of an LM358 respectively, and an output end OUT1 of the LM358 is connected IN series with a 10K resistor R11 and then connected with the inverting input end IN 1; the grounding end GND is grounded, and a 10K resistor R10 is connected IN series between the grounding end GND and the IN-phase input end IN1 < + >; the output end OUT1 is connected with a P10 port of the singlechip; the IN-phase input end In2+ is connected with a magnetic detection circuit signal of the magnet, the output end OUT2 is connected with the anti-phase input end IN 2-to form a voltage follower, and the output end OUT2 is connected with a P11 port of the singlechip; the power interface VCC is connected with a power supply, and is connected with a 0.1 mu F capacitor C6 in series and then grounded to filter out high-frequency interference; one end of the bridge type is connected with a 1K resistor R16 in series and then connected with a power supply;

2. The in-service electromagnetic ultrasonic transducer integrity detection system of claim 1, wherein: the switching circuit is composed of electromagnetic relays, and the detection circuit is switched according to the working period of the transducer; one end of the electromagnetic relay is connected with a power supply, and the other end of the electromagnetic relay is connected with a 2N3904 triode Q2 and a 10K resistor R15 in series and then connected with a P12 interface of the singlechip; the pin 4 of the connector Header2 is internally connected with the pin 5, one end of the fixed end of the sliding rheostat R17 is connected with the sliding end, meanwhile, the pin 4 of the connector Header2 is connected with the resistor R19 in the detection circuit in the period that the exciting coil is not in operation, and the other end of the sliding rheostat R17 is connected with the switch K1 knife 3 after being connected with a power supply; the switch K1 knife 1 is connected with the connector 2 pin 5; the switch K1 knife 2 is connected with the transformer L1, and the other end of the transformer L1 is connected with the connector 2 pin 4.

3. The in-service electromagnetic ultrasonic transducer integrity detection system of claim 1, wherein: the magnetic field detection circuit is used for accurately measuring the magnetic field of the magnet, and the Hall sensor 3144 module is used for measuring the magnetic field of the magnet; the power end 4 of the Hall element 3144 is connected with a power supply, the grounding end 6 is grounded, and the output end 5 is connected with the non-inverting input end 8 of the single-limit comparator; the power end 9 of the single-limit comparator is connected with a power supply and is connected with a resistor R4 with the resistance of 10K in series, the other end of the resistor R4 is connected with a light-emitting diode (LED) 1, the other end of the light-emitting diode (LED) 1 is connected with the output end 11 of the single-limit comparator, the output end 11 is also connected with a capacitor C1 with the capacitance of 0.1 mu F, and the other end of the capacitor C1 is grounded; the grounding end 10 of the single-limit comparator is grounded, the inverting input end 7 is connected with the sliding end of the sliding rheostat R3, one end of the fixed end of the sliding rheostat R3 is connected with a power supply, and the other end is grounded; the output end 11 of the single-limit comparator is also connected with the connector Header3 pin 2, the connector Header3 pin 2 is connected with the LM358 IN-phase input end In2+ IN the detection circuit during the working period of the exciting coil, the connector Header3 pin 1 is connected with a power supply, and the Header3 pin 3 is grounded.

4. The in-service electromagnetic ultrasonic transducer integrity detection system of claim 1, wherein: the buzzer alarm circuit selects a PNP type triode Q3 as a switch for conducting the buzzer LS1, namely, the base electrode end of the PNP type triode Q3 is connected in series with a resistor R22 with the resistance value of 4.7K, the other end of the resistor R22 is connected with the P32 port of the singlechip, the emitter of the triode Q3 is connected with the buzzer LS1, the other end of the buzzer LS1 is connected with a power supply, and the collector of the triode is grounded.

5. The in-service electromagnetic ultrasonic transducer integrity detection system of claim 1, wherein: the fault display circuit displays the detected fault type by adopting an LCD1602 liquid crystal screen; wherein the pin V0 is the third pin connected with the sliding end of the sliding rheostat R2, one end of the fixed end of the sliding rheostat R2 is connected with a power supply, and the other end is grounded.

6. The in-service electromagnetic ultrasonic transducer integrity detection system of claim 1, wherein: the host circuit main controller adopts a singlechip STC12C5A60S2 to collect voltage, and the singlechip carries out analog-to-digital conversion on an analog signal output by the coil detection circuit by utilizing self-contained A/D in the singlechip; the connection of the singlechip circuit accords with the connection method of the singlechip minimum system circuit, namely the grounding of the singlechip grounding end GND; the power end VCC is connected with a power supply and connected with a capacitor C2 in series, and the other end of the capacitor C2 is grounded; the pin P10 is connected with the output end OUT1 of the operational amplifier LM358 of the detection circuit during the working period of the exciting coil and the output end OUT1 of the operational amplifier LM358 of the detection circuit during the non-working period of the exciting coil, and performs analog-digital conversion on the output signal of the detection circuit of the exciting coil; the pin P11 is connected with the output end OUT2 of the detection circuit operational amplifier LM358 during the working period of the exciting coil, and the receiving signal is subjected to analog-digital conversion; the 3 pin P12 is connected with the switching circuit resistor R15 to control the electromagnetic relay to work; the reset pin 9REST is connected with a capacitor C3 with a capacitance value of 1 mu F, the reset pin 9REST is also connected with a resistor R1 with a resistance value of 10K, the other end of the resistor R1 is grounded, the other end of the capacitor C3 is connected with a power supply VCC, and the reset pin 9REST and the capacitor C3 form a reset circuit; the 12 pin P32 is connected with a buzzer alarm circuit; the 18-pin XTAL2 is connected with an external crystal oscillator Y1 and is connected with a capacitor C13 with the capacitance value of 30pF, and the other end of the capacitor C13 is grounded; the other end of the external crystal oscillator Y1 is connected with the 19-pin XTAL 1; the pin 19 is connected with a capacitor C14 with a capacitance of 30pF, and the other end of the capacitor C14 is grounded; the 18-pin XTAL2, the 19-pin XTAL1, the crystal oscillator Y1, the capacitor C13 and the capacitor C14 form an oscillating circuit; the 25 pin P24 is connected with the LED D1 and the resistor R7 with the resistance value of 1K in series and then is connected with a power supply, and the 21 pin P20, the 22 pin P21 and the 23 pin P23 are respectively connected with the double-pole double-throw switch SW-DPST in series;

7. The in-service electromagnetic ultrasonic transducer integrity detection system of claim 1, wherein: after the power supply circuit is powered on, the circuit is powered on, and a capacitor C1 with 100 mu F is connected in series to be grounded to filter high-frequency interference; the power supply is connected with a connector 4 pin 1 and is connected with a capacitor C1 with a capacitance value of 100 mu F, and the other end of the capacitor C1 is grounded; one end of the light emitting diode D4 is connected in series with a resistor R6 with the resistance value of 1K, the other end of the resistor R6 is grounded, and the other end of the light emitting diode D4 is connected with a power supply; pin 1 and pin 2 of connector Header 4 are connected; the pin 3 and the pin 4 are connected and then grounded; and the connector Header 4 leads out wires to supply power for all parts of the system.

8. An in-service electromagnetic ultrasonic transducer integrity detection system detection method as claimed in claim 1, wherein: the detection method comprises the following steps:

1) Starting a power supply circuit to supply power for the host circuit;