CN101701939A - Broad-frequency high-power electromagnetic exciting device - Google Patents
Broad-frequency high-power electromagnetic exciting device Download PDFInfo
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- CN101701939A CN101701939A CN200910272680A CN200910272680A CN101701939A CN 101701939 A CN101701939 A CN 101701939A CN 200910272680 A CN200910272680 A CN 200910272680A CN 200910272680 A CN200910272680 A CN 200910272680A CN 101701939 A CN101701939 A CN 101701939A
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Abstract
The invention belongs to the field of non-destructive testing technology and relates to a broad-frequency high-power electromagnetic exciting device which comprises a burst pulse generating circuit, an analog switch, a transformer and at least two power amplification units. Each power amplification unit comprises a signal amplification circuit, an added circuit, a current buffer, a field-effect tube voltage follower circuit and a field-effect tube current amplification circuit which are connected in sequence; each added circuit is connected with a potentiometer; the burst pulse generating circuit is connected with the input end of the analog switch; the enable end of the analog switch is connected with the output end of an over-power detection circuit; all output ends of the analog switch are respectively connected with the signal amplification circuits; the field-effect tube current amplification circuits are connected with the input end of the transformer; the input end of the over-power detection circuit is connected with one output end of the transformer; and the other output end of the transformer is used for driving a load. The exciting device can be used for the signal power amplification with a 1 KHz-20 MHz broad frequency range, and can be widely used for driving non-destructive testing sensors of ultrasonic guided wave, electromagnetic acoustic transducer and the like, and has wide application prospects.
Description
Technical field
The invention belongs to technical field of nondestructive testing, be specifically related to a kind of electromagnetic exciting device that can be used in supersonic guide-wave (GW), electromagnetic acoustic Non-Destructive Testings such as (EMAT) usefulness sensor.
Background technology
Current Dynamic Non-Destruction Measurement along with supersonic guide-wave, electromagnetic acoustic etc. is not shut down the development of detection technique and the development of pertinent instruments, presses for a kind of device that electric magnetization is provided for these detecting sensors to not shutting down the detection technique development.
In fact a kind of special power amplifier of electromagnetic exciting device, common power amplifier comprises category-A, and the AB power-like amplifier is in recent years along with the development of digital power amplifier technology and high-power FET manufacturing technology, it is higher efficient to have occurred, the littler D class of generating heat and E class power amplifier.More on the market audio frequency power amplifier and industrial power amplifier all belongs to these categories basically at present.
The audio-frequency power amplifier characteristics are to work in audiorange, promptly amplify the continuous signal of 20Hz～20KHz, the audio frequency power amplifier of higher gears its-the 3dB frequency is also less than 100KHz, because power amplifier is to amplify continuous waveform, continuous transmitted power, so thermal value is bigger, a large amount of heat radiator must be installed, its volume of transformer is also bigger, so power amplifier integral body is heavy, and power generally has only several hectowatts; Its bringing onto load is generally the audio amplifier loudspeaker, for standard 4 Europe or 8 Europe loads, is not suitable for the capacitive load occasion; In order to satisfy audience's difference taste requirement, therefore this power amplifier is not suitable for industrial circle for frequency content gain different in the audiorange and inconsistent in addition.
The frequency band that specialty is used for the another kind of power amplifier of industrial circle can reach KHz up to a hundred, yet compare with audio-frequency power amplifier, most of this power-like amplifier only is that working band is wideer, more powerful (Shang kilowatt), carrying load ability is stronger, but its framework and note amplifier do not have too big-difference.This type of power amplifier mostly is external production, the price comparison costliness.
In some special industry fields, usually need the high-power electric pulse of instantaneous pressure to drive corresponding transducer such as piezoelectric crystal or coil such as the supersonic guide-wave in the Non-Destructive Testing field, electromagnetic acoustic detection method, high-frequency sine wave (several KHz to several megahertzes) or the square wave of its pulse signal for continuing several cycles, the feature of sort signal is discontinuous, its dutycycle is usually less than per mille, but the instantaneous power of burst pulse is very high, can reach several kilowatts to tens kilowatts.Foregoing audio frequency power amplifier and traditional industry all can not undistorted amplification high-frequency signals like this with power amplifier, and so huge instantaneous power can not be provided.
Publication number is that the patent documentation of CN1775328A discloses a kind of wide focal domain phased array focusing ultrasonic transducer exciting bunk, this patent documentation is only applicable to the excitation of ultrasonic transducer, be applicable to the orientation of human body deep tumor focus, suitable shape, when long, stable heating, belong to the medicine equipment category, the emphasis of this technical scheme is to have the production method of ultrasonic action signal of given phase relation and the integral body of ultrasound phase-control system constitutes, and the VMOS field effect transistor of use is only arranged and be operated in critical C class state for the description of its power amplifying part.
Publication number is that the patent documentation of CN2660550Y discloses a kind of piezo-electric type ultrasonic probe intelligent excitation device, relates to the transmitting-receiving treatment technology of ultrasonic signal, can be used for the ultrasonic inspection and the thickness measuring field of Non-Destructive Testing.Yet this exciting bank is only applicable to the excitation of piezo-electric type ultrasonic probe, and the piezo-electric type ultrasonic probe belongs to capacitive load, so the disclosed exciting bank of the document and be not suitable for and drive inductive load such as magnetic striction wave guide and the employed coil type transducer of electromagnetic acoustic detection technique.
Summary of the invention
The objective of the invention is to the problem at the prior art existence, a kind of broad-frequency high-power electromagnetic exciting device is provided, this device can be exported the burst pulse that instantaneous power reaches several kilowatts to tens kilowatts.
Broad-frequency high-power electromagnetic exciting device provided by the invention, it is characterized in that: this device comprises burst pulse generation circuit, analog switch, transformer and at least two power amplification units, direct supply provides electric energy for device, transformer is the push-pull type output transformer, each power amplification unit includes the signal amplification circuit of connection successively, adding circuit, current buffer, field effect transistor voltage follower circuit and effect tube current amplifying circuit, each adding circuit all is connected with potentiometer, and each potentiometer is to carrying out dividing potential drop and export continuous adding circuit to from the DC voltage of direct supply;
One end of burst pulse generation circuit links to each other with direct supply, its other end links to each other with the input end of analog switch, the Enable Pin of analog switch links to each other with the output terminal of over-power detection circuit, and each output terminal of analog switch links to each other with the signal amplification circuit of each power amplification unit respectively;
The effect tube current amplifying circuit of each power amplification unit links to each other with the input end of transformer, and the input end of over-power detection circuit links to each other with an output terminal of transformer, and another output terminal of transformer is used to drive load.
The invention provides a kind of electromagnetic exciting device, can carry out power amplification to square wave and sine wave signal, reference frequency output is at 1KHz-20MHz, and instantaneous power can reach tens of kilowatts, thereby has overcome the deficiency of existing power amplifier.Apparatus of the present invention are applicable to the excitation of industrial Non-Destructive Testing sensor, are mainly used in supersonic guide-wave, the driving of electromagnetic acoustic detection method transducer, and this exciting bank can drive various perception and capacitive transducer such as coil and piezoelectric crystal.
Description of drawings
Fig. 1 is the structured flowchart of apparatus of the present invention.
Fig. 2 is the waveform of potential pulse a of bursting.
Fig. 3 is the waveform of potential pulse b of bursting.
Fig. 4 is the waveform of the potential pulse c that bursts of band biasing.
Fig. 5 is the waveform of the potential pulse d that bursts of band biasing.
Fig. 6 is the waveform of current impulse i of bursting.
Fig. 7 is the waveform of current impulse j of bursting.
Fig. 8 is the burst waveform of current impulse k of the high power of transformer output.
Embodiment
Below by by embodiment the present invention being described in further detail, but following examples only are illustrative, and protection scope of the present invention is not subjected to the restriction of these embodiment.
Be that the example explanation further specifies device of the present invention with two power amplification units below.As shown in Figure 1, this device comprises with lower module: burst pulse generation circuit 1, analog switch 2, first signal amplification circuit 3, secondary signal amplifying circuit 4, first direct supply 5, second direct supply 6, first adding circuit 7, second adding circuit 8, first current buffer 9, second current buffer 10, the first field effect transistor voltage follower circuit 11, the second field effect transistor voltage follower circuit 12, the first field effect transistor current amplification circuit 13, the second field effect transistor current amplification circuit 14, pulse type transformer 15, over-power detection circuit 16, first potentiometer 17 and second potentiometer 18.
First direct supply 5 respectively with burst pulse generation circuit 1, analog switch 2, over-power detection circuit 16, first, second amplifying circuit 3,4, first, second potentiometer 17,18, first, second current buffer 9,10 and first, second field effect transistor voltage follower circuit 11,12 link to each other, and provide its operate as normal needed generating positive and negative voltage.Second direct supply 6 links to each other with first, second field effect transistor current amplification circuit module 13,14 respectively, and provides its work needed voltage.
One end of burst pulse generation circuit 1 links to each other with first direct supply 5, its other end links to each other with the input end of analog switch 2, the Enable Pin of analog switch 2 links to each other with the output terminal of over-power detection circuit 16, and two output terminals link to each other with the input end of first, second amplifying circuit 3,4 respectively.The output terminal of first amplifying circuit 3 links to each other with the first input end of first input end, first current buffer 9, the first field effect transistor voltage follower circuit 11, the first field effect transistor current amplification circuit 13 and the transformer 15 of first adding circuit 7 successively, and the output terminal of second amplifying circuit 4 links to each other with second input end of first input end, second current buffer 10, the second field effect transistor voltage follower circuit 12, the second field effect transistor current amplification circuit 14 and the transformer 15 of second adding circuit 8 successively.
The input end of over-power detection circuit 16 links to each other with an output terminal of transformer 15, and another output terminal of transformer 15 is used to drive load.
The input end of first, second potentiometer 17,18 links to each other with direct supply 5 respectively, and output terminal links to each other with second input end of first, second adding circuit 7,8 respectively.
Burst pulse generation circuit 1 is by direct supply 5 power supplies, and repetition frequency is specified according to the user in the back that powers on, and the sine wave freuqency of appointment and amplitude send the voltage pulse signal of bursting to analog switch 2.The burst repetition frequency of potential pulse, sine wave freuqency and amplitude can be set by the user.
Analog switch 2 is electronic switches, according to the control signal conducting of over-power detection circuit 16 or close.When Enable Pin input opening signal, not conducting of analog switch, it is output as high-impedance state; When Enable Pin input closure signal, the analog switch conducting, the voltage pulse signal of will bursting is transmitted to first, second signal amplification circuit 3,4 respectively.
First signal amplification circuit 3 is in-phase voltage amplifying circuits, exports first adding circuit 7 to after the voltage pulse signal homophase of bursting that it will receive amplifies.
Secondary signal amplifying circuit 4 is reverse voltage amplifying circuits, exports second adding circuit 8 to after the anti-phase amplification of the voltage pulse signal of bursting that it will receive.
17,18 pairs of DC voltage from direct supply 5 of first, second potentiometer are carried out dividing potential drop and are exported first, second adding circuit 7,8 to, by regulating first, second potentiometer 17,18, can regulate the size of direct current biasing composition of the voltage pulse signal of bursting with direct current biasing of first, second adding circuit output respectively.
First adding circuit 7 has identical structure with second adding circuit 8, and its output voltage signal is the algebraic sum of its input voltage signal.Burst voltage pulse signal and the stable direct current biasing addition that comes from first, second potentiometer 17,18 that they all will receive obtain having the voltage pulse signal of bursting of direct current biasing, and export first, second current buffer 9,10 respectively to.
First current buffer 9 has identical structure with second current buffer 10, and they strengthen the current driving ability of the voltage pulse signal of bursting with direct current biasing that receives, and export first, second field effect transistor voltage follower circuit 11,12 respectively to.
First, second field effect transistor voltage follower circuit 11,12 has identical structure, they will further strengthen the current driving ability of the voltage pulse signal of bursting with direct current biasing of reception, and export first, second field effect transistor current amplification circuit 13,14 respectively.
Current buffer and field effect transistor voltage follower circuit can strengthen the current driving ability of output voltage signal, so that give the grid and the charging of source class junction capacity of field effect transistor fast, alleviate junction capacity and discharge and recharge the influence of effect to the signal radio-frequency component.
First, second field effect transistor current amplification circuit 13,14 has identical structure, because the inherent characteristic of field effect transistor, this current amplification circuit can not amplify the part that amplitude in its input voltage signal is lower than its critical voltage that opens the door.By regulating first, second potentiometer 17,18 respectively, can be respectively the direct current biasing composition of the input signal of first, second field effect transistor current amplification circuit 13,14 be adjusted to the critical voltage that opens the door of field effect transistor current amplification circuit and equates, make first, second field effect transistor current amplification circuit that suitable quiescent point be arranged.The input signal of field effect tube current amplifying circuit is the voltage pulse signal of bursting with direct current biasing in this device, the direct current biasing composition of signal will can not be converted to current signal, the alternating component of signal is the voltage pulse signal of bursting, will change and be enlarged into the current pulse signal of bursting, and export transformer 15 to.The output amplitude of current pulse signal of bursting can reach more than the 20A, so just can realize high-power output.Because the alternating component in the input signal of first, second field effect transistor current amplification circuit 13,14 is an inversion signal, two amplifying circuits amplify the part that is higher than its critical voltage that opens the door in the alternating component respectively, make 90 ° of phase phasic differences between the current output signal of two amplifying circuits.
Transformer 15 is push-pull type output transformers, the shared one group of secondary coil of its two groups of primary coils, from field effect transistor amplification circuit 13 and 14 output two-way mutually 90 ° of current signals of phasic difference import its two groups of input coils respectively, according to the basic functional principle of transformer, can synthesize the complete high-power current signal of bursting at output terminal;
Over-power detection circuit 16 links to each other with analog switch 2, and the output of its monitoring pulse type transformer 15 is also calculated its output power in real time, sends the signal that disconnects analog switch 2 when the output power overrate, thereby reaches the purpose of this device of protection.
The course of work of this device is as follows:
Send into first, second signal amplification circuit 3,4 generation two-way amplitudes from the potential pulse of bursting of burst pulse generation circuit 1 generation respectively by analog switch 2 and equate, burst potential pulse a and b that phase place is opposite, as shown in Figures 2 and 3.
Regulate first, second potentiometer and make its output be respectively Vb1, Vb2, wherein Vb1, Vb2 equate with the critical voltage that opens the door of first, second field effect transistor current amplification circuit respectively.The potential pulse a that bursts becomes the potential pulse c that bursts that is superimposed on certain dc offset voltage Vb1 after sending into first adding circuit 7, as shown in Figure 4, in like manner, the potential pulse b that bursts becomes the potential pulse d that bursts that is superimposed on certain dc offset voltage Vb2 after sending into second adding circuit 8, the alternating component phase place of potential pulse c, d of bursting is opposite, as shown in Figure 5.
The current driving ability of potential pulse c, d has only several milliamperes owing to burst, and can't directly drive follow-up field effect transistor circuit, therefore, needs to strengthen the current driving ability of burst potential pulse c, d.This device uses first, second current buffer 9,10, and first, second field effect transistor voltage follower circuit 11,12 strengthens the current driving ability of burst potential pulse c, d.The potential pulse c that bursts sends into first current buffer 9 becomes the potential pulse e that bursts with 70 milliamperes of current driving abilities, and in like manner, the potential pulse d that bursts sends into second current buffer 10 becomes the potential pulse f that bursts with 70 milliamperes of current driving abilities.The potential pulse e that bursts becomes the potential pulse g that bursts with 250 milliamperes of current driving abilities after sending into the first field effect transistor voltage follower circuit 11, in like manner, burst and become the potential pulse h that bursts after potential pulse f sends into the second field effect transistor voltage follower circuit 12 with 250 milliamperes of current driving abilities.
The potential pulse g that bursts sends into the first field effect transistor current amplification circuit 13, because circuit 13 can not amplify the part that is lower than its critical voltage that opens the door among the potential pulse g that bursts, therefore circuit 13 is converted to amplitude with the part that is higher than its critical voltage that opens the door among the burst pulse g and can reaches the current impulse i that bursts more than 20 amperes, as shown in Figure 6.In like manner, the potential pulse h that bursts sends into the second field effect transistor current amplification circuit 14, and circuit 14 is converted to amplitude with the part that is higher than its critical voltage that opens the door among the burst pulse h can reach the current impulse j that bursts more than 20 amperes, as shown in Figure 7.
Burst current impulse i and j sends into two input ends of transformer 15 respectively, because the current impulse i that bursts, the amplitude of j equates and 90 ° of phase phasic differences, so the output winding of transformer 15 can synthesize the complete current impulse k that bursts, as shown in Figure 8.That this current impulse of bursting can be used for driving is resistive, perception and capacitive load such as various Non-Destructive Testing sensor.
Over-power detection circuit 16 is the voltage waveform and the current waveform of monitoring transformer 15 output terminals in real time, and calculates its output power, turn-offs analog switch when the output power overrate rapidly, and anti-locking apparatus is burnt.
Employed each functional module of this device, because electronic component is selected and the physical circuit configuration flexibility, might use other electronic devices and components also can realize identical functions of modules, for example, burst pulse generation circuit 1 can use various commercial signal generation apparatus or use such as 8038 and build with some DDS chip; Circuit 3,4,7,8 outside impact damper 9, the 10 division operation amplifiers, also can use other components and parts with enlarging function such as various triode and field effect transistor to build, and the integrated circuit (IC) chip that also may use some directly to realize required function is in addition built; Circuit 11,12,13,14 except that field effect transistor, can use such as IGBT and large power triode and build, and first, second direct supply also can adopt a direct supply with many outputs to replace.Therefore, owing to electronic component and circuit arrangement change the intimate exciting bank that constitutes should be in protection scope of the present invention.
This device needs at least the two-way field effect transistor in order to synthetic complete high-power burst pulse waveform, yet by with some field effect transistor parallel connections, can promote the peak power output of this broad-frequency high-power electromagnetic exciting device.Therefore the exciting bank that is made of the field effect transistor more than two-way should be in protection scope of the present invention.
The over-power detection circuit of this device can prevent to surpass the accident that the rated power of device causes output stage to burn because of output when load is overweight; this installs employed salvo is to control the break-make of light current level burst pulse by analog switch; yet protected mode is not limited thereto, and can also comprise that the power circuit to whole device carries out break-make control in modes such as relays.
Owing to electronic component and circuit arrangement change the intimate exciting bank that constitutes should be in protection scope of the present invention.
The above is preferred embodiment of the present invention, but the present invention should not be confined to the disclosed content of this embodiment and accompanying drawing.So everyly do not break away from the equivalence of finishing under the spirit disclosed in this invention or revise, all fall into the scope of protection of the invention.
Claims (1)
1. broad-frequency high-power electromagnetic exciting device, it is characterized in that: this device comprises burst pulse generation circuit, analog switch, transformer and at least two power amplification units, direct supply provides electric energy for device, transformer is the push-pull type output transformer, each power amplification unit includes the signal amplification circuit of connection successively, adding circuit, current buffer, field effect transistor voltage follower circuit and effect tube current amplifying circuit, each adding circuit all is connected with potentiometer, and each potentiometer is to carrying out dividing potential drop and export continuous adding circuit to from the DC voltage of direct supply;
One end of burst pulse generation circuit links to each other with direct supply, its other end links to each other with the input end of analog switch, the Enable Pin of analog switch links to each other with the output terminal of over-power detection circuit, and each output terminal of analog switch links to each other with the signal amplification circuit of each power amplification unit respectively;
The effect tube current amplifying circuit of each power amplification unit links to each other with the input end of transformer, and the input end of over-power detection circuit links to each other with an output terminal of transformer, and another output terminal of transformer is used to drive load.
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| CN2009102726801A CN101701939B (en) | 2009-11-06 | 2009-11-06 | Broad-frequency high-power electromagnetic exciting device |
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| CN2009102726801A CN101701939B (en) | 2009-11-06 | 2009-11-06 | Broad-frequency high-power electromagnetic exciting device |
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| CN101701939B CN101701939B (en) | 2011-07-20 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102565200A (en) * | 2012-02-15 | 2012-07-11 | 北京工业大学 | Arbitrary waveform excitation board card for exciting piezoelectric transducer array to generate ultrasonic guided waves |
| CN102621237A (en) * | 2012-03-12 | 2012-08-01 | 河海大学常州校区 | High-power single-pulse ultrasonic signal generator and nondestructive inspection method thereof |
| CN106257235A (en) * | 2016-08-31 | 2016-12-28 | 中国特种设备检测研究院 | The high-power driving source of pulsed electromagnetic acoustic |
| CN106442742A (en) * | 2016-08-31 | 2017-02-22 | 中国特种设备检测研究院 | 100kW-grade broad-band electromagnetic ultrasonic excitation source |
| CN109078271A (en) * | 2017-06-13 | 2018-12-25 | 上海沈德医疗器械科技有限公司 | A kind of phase-control focusing ultrasound-driven circuit of magnetic resonance compatible |
| CN114129920A (en) * | 2021-11-29 | 2022-03-04 | 中国医学科学院生物医学工程研究所 | Phased array ultrasonic transducer excitation system for improving accurate frequency |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101109731B (en) * | 2007-08-08 | 2010-12-01 | 哈尔滨工业大学 | Gabor translating self-adapting window width selecting method represented by ultrasound signal |
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2009
- 2009-11-06 CN CN2009102726801A patent/CN101701939B/en not_active Expired - Fee Related
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102565200A (en) * | 2012-02-15 | 2012-07-11 | 北京工业大学 | Arbitrary waveform excitation board card for exciting piezoelectric transducer array to generate ultrasonic guided waves |
| CN102621237A (en) * | 2012-03-12 | 2012-08-01 | 河海大学常州校区 | High-power single-pulse ultrasonic signal generator and nondestructive inspection method thereof |
| CN106257235A (en) * | 2016-08-31 | 2016-12-28 | 中国特种设备检测研究院 | The high-power driving source of pulsed electromagnetic acoustic |
| CN106442742A (en) * | 2016-08-31 | 2017-02-22 | 中国特种设备检测研究院 | 100kW-grade broad-band electromagnetic ultrasonic excitation source |
| CN106257235B (en) * | 2016-08-31 | 2019-08-30 | 中国特种设备检测研究院 | The high-power driving source of pulsed electromagnetic acoustic |
| CN106442742B (en) * | 2016-08-31 | 2023-11-03 | 中国特种设备检测研究院 | 100 kW-level broadband electromagnetic ultrasonic excitation source |
| CN109078271A (en) * | 2017-06-13 | 2018-12-25 | 上海沈德医疗器械科技有限公司 | A kind of phase-control focusing ultrasound-driven circuit of magnetic resonance compatible |
| CN109078271B (en) * | 2017-06-13 | 2020-08-07 | 上海沈德医疗器械科技有限公司 | Phase-controlled focusing ultrasonic drive circuit compatible with magnetic resonance |
| CN114129920A (en) * | 2021-11-29 | 2022-03-04 | 中国医学科学院生物医学工程研究所 | Phased array ultrasonic transducer excitation system for improving accurate frequency |
| CN114129920B (en) * | 2021-11-29 | 2023-09-26 | 中国医学科学院生物医学工程研究所 | Phased array ultrasonic transducer excitation system for improving accurate frequency |
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