CN111123371A - High-quality emission waveform dragging type electromagnetic detection device and detection method - Google Patents

High-quality emission waveform dragging type electromagnetic detection device and detection method Download PDF

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CN111123371A
CN111123371A CN201911367392.4A CN201911367392A CN111123371A CN 111123371 A CN111123371 A CN 111123371A CN 201911367392 A CN201911367392 A CN 201911367392A CN 111123371 A CN111123371 A CN 111123371A
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emission
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CN111123371B (en
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张洋
严复雪
李苏杭
林君
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Jilin University
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Jilin University
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    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V3/00—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation
    • G01V3/15—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation specially adapted for use during transport, e.g. by a person, vehicle or boat
    • G01V3/165—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation specially adapted for use during transport, e.g. by a person, vehicle or boat operating with magnetic or electric fields produced or modified by the object or by the detecting device

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Abstract

The invention relates to the technical field of geophysical electromagnetic detection, in particular to a dragging type electromagnetic detection device and a detection method for high-quality emission waveforms, which comprises a main control module, a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a seventh; the second switch is driven to be controlled to be switched on or switched off through the second switch, whether the main DC-DC is connected with a circuit or not is controlled, and power is supplied to the emission system when the emission current reaches the current flat top stage, so that the emission system emits stable current; the third switch is driven to be controlled to be switched on or switched off through the third switch, and whether the clamping DC-DC is connected into the circuit or not is controlled, so that voltage clamping is carried out at the current quick turn-off stage, and the emission current of the emission system is quickly turned off; the problem that effective excitation is difficult to form under the high-frequency condition is solved.

Description

High-quality emission waveform dragging type electromagnetic detection device and detection method
Technical Field
The invention relates to the technical field of geophysical electromagnetic detection, in particular to a towed electromagnetic detection device and a detection method for high-quality emission waveforms.
Background
With the development of urbanization, the ground space is limited, and the development of urban underground space has become a trend. Before development, the urban underground space is subjected to non-invasive detection and underground medium distribution description by utilizing a geophysical method, and the method has important significance. As a typical geophysical method, particularly a towed transient electromagnetic detection method, an electromagnetic method has the advantages of large detection depth, convenience in working and the like in urban underground space detection compared with methods such as ground penetrating radar and shallow earthquake.
In order to improve the detection efficiency and the lateral resolution in urban detection, the towed electromagnetic system needs to move at a high speed and to perform intensive measurement work, and therefore needs to transmit high-frequency pulses. However, under the condition of a fixed structure of the transmitting coil, the rising speed of the transmitting current depends on the magnitude of the transmitting voltage, and under the condition of higher transmitting frequency, the transmitting period is short, the transmitting current is difficult to quickly reach a stable state, so that the duration of a flat-top stage of the transmitting waveform is short, and even the flat-top stage cannot be reached, thereby causing poor quality of the transmitting waveform, difficult formation of effective excitation, and serious influence on the detection effect.
Disclosure of Invention
In view of the above-mentioned deficiencies of the prior art, the present invention provides a towed electromagnetic probe for detecting high-quality transmitted waveforms, and another aspect of the present invention provides a towed electromagnetic probe for detecting high-quality transmitted waveforms.
The present invention is achieved in such a way that,
a towed electromagnetic survey apparatus for high quality transmit waveforms including a receiving system having a receiving coil and a transmitting system having a transmitting coil, the apparatus comprising: the high-voltage DC-DC power supply comprises a main control module, an upper computer, a power supply, a first switch driver, a second switch driver, a third switch driver, a first switch, a second switch, a third switch, a first protection diode, a second protection diode, a third protection diode, a high-voltage DC-DC, a main DC-DC, a clamping DC-DC, a PWM driver and an H-bridge emission module;
wherein, the upper computer transmits the parameters required by the system operation into the main control module and receives the data returned from the main control module,
the power supply is used for connecting through the main control module;
the first switch drive is used for driving a first switch, and the first switch is connected with the H-bridge transmitting module through a first protection diode and a high-voltage DC-DC;
the second switch drive is used for driving a second switch, and the second switch is connected with the H-bridge transmitting module through a second protection diode and a main DC-DC;
the third switch driver is used for driving a third switch, and the third switch is connected with the H-bridge emission module through a third protection diode and a clamping DC-DC;
the H-bridge emission module comprises a transistor Q1 and a transistor Q2 which are connected in series, a transistor Q3 and a transistor Q4 which are connected in series, one end of an emission coil is connected between the transistor Q1 and the transistor Q2, and the other end of the emission coil is connected between the transistor Q3 and the transistor Q4; the transistor Q1 and the transistor Q3 are connected to the first switch, the second switch and the third switch; the transistor Q2 and the transistor Q4 are respectively connected with the high-voltage DC-DC, the main DC-DC and the clamp DC-DC to form an H bridge;
the main control module controls the first switch to be switched on or switched off through the first switch drive, controls whether the high-voltage DC-DC is connected into a circuit or not, and supplies power to the transmitting system and guides the transmitting current to rapidly rise when the transmitting current reaches the stage of rapidly rising the current; the second switch is driven to be controlled to be switched on or switched off through the second switch, whether the main DC-DC is connected with a circuit or not is controlled, and power is supplied to the emission system when the emission current reaches the current flat top stage, so that the emission system emits stable current; the third switch is driven to be controlled to be switched on or switched off through the third switch, and whether the clamping DC-DC is connected into the circuit or not is controlled, so that voltage clamping is carried out at the current quick turn-off stage, and the emission current of the emission system is quickly turned off;
the main control module generates PWM signals with adjustable frequency and duty ratio, the H-bridge emission module is driven and controlled to work through the PWM signals, corresponding bipolar emission current is generated, and an excitation magnetic field is generated through the emission coil.
A method of towed electromagnetic surveying of high quality transmit waveforms, the method comprising: according to the emission time sequence, in a period T, bipolar pulse emission is carried out once, and when the emission current reaches the stage of rapid current rise, high-voltage power supply is carried out on an emission system, and the emission current is guided to rise rapidly;
when the emission current reaches the stage of current flat top, the main voltage of the emission system is supplied with power, so that the emission system emits stable current;
and voltage clamping is carried out at the stage of quickly turning off the emission current, so that the emission current of an emission system is quickly turned off.
Further, the pulse transmission in a single period specifically includes:
step 401, a main control module closes a first switch through driving of the first switch, opens the switch through driving of a second switch, opens a third switch through driving of the third switch, connects a high-voltage DC-DC into a circuit, and prepares for positive pulse emission;
step 402, starting the emission of positive pulses, wherein t is 0, and preparing to enter a current rapid rising stage;
step 403, determining whether the current rises to the magnitude of the switchable emission current, if so, performing step 404, otherwise, repeating the step, and determining whether the amplitude of the current I reaches the current I according to the determination result1；I1Switching the current for the positive half cycle;
step 404, the main control module switches off the first switch through the driving of the first switch, switches on the second switch through the driving of the second switch, switches off the switch through the driving of the third switch, connects the main DC-DC to the circuit, and enters a current flat stage;
step 405, determining whether the PWMA signal controlling the transistor Q1 and the transistor Q2 is finished, if yes, performing step 406, otherwise, repeatedly executing the step, and determining the result as the falling edge of the PWMA signal;
step 406, the main control module disconnects the first switch through the driving of the first switch, disconnects the second switch through the driving of the second switch, closes the third switch through the driving of the third switch, and at the moment, clamps the DC-DC connection circuit to prepare to enter a current rapid turn-off stage;
step 407, judging whether the emission current of the positive half period is turned off, if so, performing step 408, otherwise, repeating the step;
step 408, the main control module closes the third switch through the driving of the third switch, disconnects the first switch through the driving of the first switch, disconnects the second switch through the driving of the second switch, and at the moment, the high-voltage DC-DC is connected into the circuit to prepare for entering a signal acquisition stage;
step 409, judging whether the signal acquisition is finished, if so, performing step 410, otherwise, repeating the step, and judging whether the emission time T is equal to T/2 or not according to the judgment criterion;
step 410, the main control module keeps the switch driving state unchanged, starts the emission of the negative pulse and prepares to enter a current rapid rising stage;
step 411, determining whether the current rises to the magnitude of the switchable emission current, if so, performing step 412, otherwise, repeating the step, and determining whether the amplitude of the current I reaches I or not2(ii) a Wherein, I2Switching the current for a negative half cycle;
step 412, the main control module disconnects the first switch through the driving of the first switch, closes the second switch through the driving of the second switch, and disconnects the third switch through the driving of the third switch, and at the moment, the main DC-DC is connected into the circuit to prepare for entering a current flat-top stage;
step 413, judging whether the PWMB signal for controlling the transistor Q3 and the transistor Q2 is finished, if so, executing step 414, otherwise, repeating the step and judging the signal as the falling edge of the PWMB signal;
step 414, the main control module disconnects the first switch through the first switch drive, disconnects the second switch S2 through the second switch drive, and closes the third switch through the third switch drive, and at this time, the clamp DC-DC is connected to the circuit to prepare for entering a current fast turn-off stage;
step 415, judging whether the emission current of the negative half period is turned off, if so, performing step 416, otherwise, repeating the step, and judging that the amplitude of the current I is reduced to 0 according to the judgment;
step 416, the main control module closes the third switch through the driving of the third switch, disconnects the first switch through the driving of the first switch, disconnects the second switch through the driving of the second switch, and at the moment, the high-voltage DC-DC is connected into the circuit to prepare for entering a signal acquisition stage;
step 417, judging whether the signal acquisition is finished, if so, performing step 418, otherwise, repeating the step, and judging whether the transmitting time T is equal to T or not;
and step 418, finishing the signal acquisition of the receiving coil and finishing the current emission of a single period.
Further, the voltage value U of the high voltage DC-DC1Voltage value U of main DC-DC2And clamping the voltage value U of the DC-DC3The following relationship is satisfied:
I10＝I0，I20＝-I0，I1＝mI10，I2＝mI20，tup＝nDT，
Figure BDA0002338794900000051
U2＝RrI0，
Figure BDA0002338794900000052
wherein R isrIs an equivalent resistance of the transmitting coil, LrIs equivalent inductance of a transmitting coil, f is transmitting current frequency, T is transmitting current period, T is 1/f, D is transmitting current duty ratio, T is equivalent inductance of a transmitting coilupTo emit the current rise time, toffFor emission current off-time, I0For the magnitude of the emission current, I10For emission of current for positive half-cycles, I20For emission of current in negative half-cycles, I1Switching the current for positive half-cycles2For negative half-cycle switching current, m is the proportionality coefficient of the current and the emission current when switching from high-voltage DC-DC to main DC-DC, n is the proportionality coefficient of the required rise time to the whole current emission time,
further, in step 403, the current I in the transmitting coil gradually increases under the action of the high voltage DC-DC, and assuming that the current direction in the coil is a forward direction, the magnitude of the current I satisfies:
Figure BDA0002338794900000053
further, in step 411, the current I in the transmitting coil gradually increases under the action of the high voltage DC-DC, at this time, the current direction in the coil is reverse, and the magnitude of the current I satisfies the formula:
Figure BDA0002338794900000054
compared with the prior art, the invention has the beneficial effects that:
according to the towing type electromagnetic detection device and method for the high-quality emission waveform, high-voltage DC-DC power supply is adopted in the rapid emission current rising stage, main DC-DC power supply is adopted in the current emission flat top stage, the rising speed of the emission current is effectively improved under the condition that the size of the excitation current is not changed, the rising time of the emission current reaching the flat top stage is shortened, and the problem that effective excitation is difficult to form under the high-frequency condition is solved;
additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
FIG. 1 shows a schematic block diagram of a circuit portion of a towed electromagnetic survey apparatus of high quality transmit waveforms in accordance with one embodiment of the present invention;
FIG. 2 shows an overall schematic block diagram of a towed electromagnetic survey apparatus of high quality transmit waveforms in accordance with one embodiment of the present invention;
FIG. 3 shows a schematic flow diagram of the transmission of a pulse of a towed electromagnetic survey method of high quality transmit waveforms in accordance with an embodiment of the present invention;
FIG. 4 shows a schematic flow diagram of the transmission of a pulse of a towed electromagnetic survey method of high quality transmit waveforms in accordance with an embodiment of the present invention;
FIG. 5 shows a transmit timing diagram of a towed electromagnetic survey method of high quality transmit waveforms in accordance with an embodiment of the present invention.
Detailed Description
In order that the above objects, features and advantages of the present invention can be more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Referring to fig. 1 and 2, there is shown a circuit portion and an overall schematic block diagram of a high quality transmit waveform towed electromagnetic probe apparatus of the present invention; a quick high accuracy towed array electromagnetic surveying device of city underground space, the device includes: the system comprises an electromagnetic transmitting and receiving control system, a transmitting coil 19, a receiving coil 22, a moving platform 23 and a towing vehicle 24, wherein the electromagnetic transmitting and receiving control system is composed of a main control module 1, an upper computer 2, a storage battery 3, a first switch driver 4, a second switch driver 5, a third switch driver 6, a first switch 7, a second switch 8, a third switch 9, a first protection diode 10, a second protection diode 11, a third protection diode 12, a high-voltage DC-DC13, a main DC-DC14, a clamping DC-DC15, a PWM driver 16, an H-bridge transmitting module 17, a current sensor 18, an A/D acquisition module 20 and a preamplifier 21.
Wherein, on the connection system, the main control module 1 is respectively connected with the upper computer 2, the battery 3, the first switch driver 4, the second switch driver 5, the third switch driver 6, the high voltage DC-DC13, the main DC-DC14, the clamp DC-DC15, the H bridge emission module 17, the current sensor 18 and the A/D acquisition module 20, the PWM driver 16 is connected with the emission coil 19 through the H bridge emission module 17, the first switch driver 4 is connected with the first switch 7, the second switch driver 5 is connected with the second switch 8, the third switch driver 6 is connected with the third switch 9, the first switch 7 is connected with the high voltage DC-DC13 through the first protection diode 10, the second switch 8 is connected with the main DC-DC14 through the second protection diode 11, the third switch 9 is connected with the clamp DC-DC15 through the third protection diode 12, the A/D acquisition module 20 is connected with the preamplifier 21, the preamplifier 21 is connected to the receiving coil 22.
The main control module 1 mainly comprises a DSP and an FPGA and controls the whole electromagnetic detection device to work in order;
the main control module 1 controls the first switch 7 to be switched on or switched off through the first switch driver 4, so as to control whether the high-voltage DC-DC13 is connected into a circuit or not, and the purposes of supplying power to a system and guiding the emission current to quickly rise in the current quick rise stage are achieved; the second switch 8 is controlled to be switched on or switched off through the second switch driver 5, so that whether the main DC-DC14 is connected into a circuit or not is controlled, and the purposes of supplying power to the system and enabling the system to emit stable current in the current flat-top stage are achieved; the third switch 9 is controlled to be closed or opened through the third switch driver 6, so that whether the clamp DC-DC15 is connected into a circuit or not is controlled, and the purposes of performing voltage clamp in the current quick turn-off stage and quickly turning off the system emission current are achieved;
the main control module 1 generates a PWM signal with adjustable frequency and duty ratio, and drives and controls the H-bridge transmitting module 17 to work through PWM to generate corresponding bipolar transmitting current, so as to generate an excitation magnetic field through the transmitting coil 19;
the main control module 1 monitors the current waveform of the transmitting coil 19 through the current sensor 18;
the main control module 1 is used for amplifying and collecting signals sensed by the receiving coil 22 by controlling the preamplifier 21 and the A/D collecting module 20;
the first protection diode 10 prevents the circuit from being damaged by overlarge voltage when the high-voltage DC-DC13 is connected into the circuit, and protects the circuit;
a second protection diode 11 for preventing the circuit from being damaged by reverse charging when the voltage is too high and the main DC-DC14 is switched to the high-voltage DC-DC when the main DC-DC14 is connected into the circuit;
a third protection diode 12 for protecting the circuit from damage caused by excessive voltage when the clamp DC-DC15 is connected to the circuit;
the upper computer 2 is used for realizing man-machine interaction, transmitting parameters required by system operation into the main control module, receiving and displaying data returned from the main control module;
the battery 3 is used for supplying power to the main control module 1;
a receiving coil 22 for receiving a secondary field signal generated by the transmitting coil exciting through the underground medium, thereby obtaining geological information of the underground;
the moving platform 23 consists of a non-metal frame and wheels, is loaded with a transmitting coil and a receiving coil for moving measurement, avoids laying the coils manually, and improves the detection efficiency;
the towing vehicle 24, which may be an unmanned vehicle, a human-driven vehicle, or a human-powered trailer, carries the electromagnetic transmit and receive control system and is used to tow the mobile platform.
Referring to fig. 3, the invention provides a fast and high-precision towed array electromagnetic detection method for urban underground space by adopting the device, which comprises the following steps:
step 301, after the instruments are connected, transmitting current I is input through an upper computer0Parameters such as the transmitting period number Q and the excitation frequency f are transmitted into a master control system;
step 302, the master control system adjusts the high voltage DC-DC value U according to the input parameters1Main DC-DC value U2And clamping the DC-DC value U3They satisfy the following relationship:
I10＝I0，I20＝-I0，I1＝mI10，I2＝mI20，tup＝nDT，
Figure BDA0002338794900000081
U2＝RrI0，
Figure BDA0002338794900000082
wherein R isrIs an equivalent resistance of the transmitting coil, LrIs equivalent inductance of a transmitting coil, f is transmitting current frequency, T is transmitting current period, T is 1/f, D is transmitting current duty ratio, T is equivalent inductance of a transmitting coilupTo emit the current rise time, toffFor emission current off-time, I0For the magnitude of the emission current, I10For emission of current for positive half-cycles, I20For emission of current in negative half-cycles, I1Switching the current for positive half-cycles2For negative half-cycle switching current, m is the proportionality coefficient of the current and the emission current when switching from high-voltage DC-DC to main DC-DC, n is the proportionality coefficient of the required rise time to the whole current emission time,
wherein, m and n are adjusted according to the actual situation due to the problems of inconsistent hardware switching time, required current rising speed and the like;
step 303, continuously collecting the current of the transmitting coil by using a current sensor, and starting current detection on the main control through the current sensor;
at step 304, the transmit pulse is initiated. Referring to fig. 4, in a period T, a bipolar pulse transmission is performed, where T is an excitation pulse period, the H-bridge transmission module control signal is Q (PWMA, PWMB), the first switch 7 (switch S1) control signal is S1, the second switch 8 (switch S2) control signal is S2, and the third switch 9 (switch S3) control signal is S3, and the pulse transmission steps in a single period are as follows:
step 401, the main control module closes the switch S1 through the first switch drive, opens the switch S2 through the second switch drive, and opens the switch S3 through the third switch drive, at this time, the high voltage DC-DC is connected to the circuit to prepare for positive pulse emission;
step 402, starting the emission of the positive pulse, referring to fig. 5, when t is t1 and the current I is 0, and preparing to enter a current fast rising stage;
step 403, determining whether the current rises to the switchable emission current, if so, performing step 404, otherwise, repeating the step, and determining whether the amplitude of the current I reaches I or not1This step is further explained below with reference to fig. 5:
in the time t1-t2, the PWMA signal of the transistor Q1 and the transistor Q4 is controlled to be active, the signal of the switch S1 is controlled to be active, the PWMB signal of the transistor Q2 and the transistor Q3 and the signals of the switches S2 and S3 are controlled to be inactive, the transistor Q1 and the transistor Q4 are turned on, the transistor Q2 and the transistor Q3 are turned off, the switch S1 is turned on, the switches S2 and S3 are turned off, the coil, the transistor Q1, the transistor Q4, the switch S1 and the high-voltage DC-DC form a loop, the current I in the coil gradually increases under the action of the high-voltage DC-DC, the current direction in the coil is set to be positive, and the amplitude of the current I meets the following:
Figure BDA0002338794900000101
when t is t2, the current I is I1When the current reaches the condition of switchable emission current;
step 404, the main control module turns off the switch S1 through the first switch drive, turns on the switch S2 through the second switch drive, and turns off the switch S3 through the third switch drive, and at this time, the main DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t2, and it is ready to enter the current flat-top stage;
step 405, determining whether PWMA is finished, if yes, performing step 406, otherwise, repeatedly executing the step, and determining that the PWMA is a falling edge, which will be further described with reference to fig. 5:
in the time t2-t3, the PWMA signal of the transistor Q1 and the transistor Q4 is controlled to be effective, the signal of the control switch S2 is controlled to be effective, the PWMB signal of the transistor Q2 and the transistor Q3 is controlled and the signals of the control switches S1 and S3 are controlled to be ineffective, at the moment, the transistor Q1 and the transistor Q4 are switched on, the transistor Q2 and the transistor Q3 are switched off, the switch S1 is switched off, the switch S2 is switched on, the switch S3 is switched off, a coil, the transistor Q1, the transistors Q4 and S2 and the main DC form a loop, the current in the coil is kept stable under the action of the main DC-DC, and the emission current is in a flat,
when t is t3, PWMA generates a falling edge, and the condition that PWMA ends is met;
step 406, the main control module turns off the switch S1 through the first switch drive, turns off the switch S2 through the second switch drive, and turns on the switch S3 through the third switch drive, and at this time, the clamp DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t3, and it is ready to enter the current fast turn-off stage;
step 407, determining whether the emission current of the positive half period is turned off, if so, performing step 408, otherwise, repeating the step, and determining that the amplitude of the current I is reduced to 0 according to the determination. This step is further explained below with reference to fig. 5:
in the time t3-t4, the signal for controlling the switch S3 is effective, the PWMA and PWMB signals for controlling the Q1-Q4 and the signals for controlling the switch S1 and the switch S2 are ineffective, at this time, the Q1-Q4 are cut off, the switch S2 is cut off, the switch S3 is turned on, the switch S1 is cut off, the transmitting coil, the switch S3 and the clamp DC-DC form a loop, the coil discharges electricity through the loop, and the current in the transmitting coil is gradually reduced under the action of the clamp DC-DC;
when t is t4, the current in the coil is reduced to 0, and the condition that the emission current is turned off in the positive half period is met;
step 408, the main control module closes the switch S3 through the third switch drive, opens the switch S1 through the first switch drive, and opens the switch S2 through the second switch drive, and at this time, the high-voltage DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t4, and it is ready to enter the signal acquisition stage;
step 409, judging whether the signal acquisition is finished, if so, performing step 410, otherwise, repeating the step, and judging whether the emission time T is equal to T/2 according to the judgment basis. This step is further explained below with reference to fig. 5:
in the time T4-T/2, signals of a control switch S1 are effective, PWMA and PWMB signals of control Q1-Q4 and signals of a control switch S2 and a control switch S3 are ineffective, at the moment, Q1-Q4 are cut off, a switch S3 is cut off, a switch S1 is turned on, a switch S2 is cut off, and the system collects signals through a receiving coil;
when T is T/2, the signal acquisition of the receiving coil is finished;
step 410, the main control module keeps the switch driving state unchanged, starts the emission of the negative pulse, and prepares to enter a current rapid rising stage, referring to fig. 5, when T is T/2;
step 411, determining whether the current rises to the magnitude of the switchable emission current, if so, performing step 412, otherwise, repeating the step, and determining whether the amplitude of the current I reaches I or not2This step is further explained below with reference to fig. 5:
in the time T/2-T5, the PWMB signal of the transistor Q2 and the transistor Q3 is controlled to be effective, the signal of the switch S1 is controlled to be effective, the PWMA signal of the transistor Q1 and the transistor Q4 and the signals of the switches S2 and S3 are controlled to be ineffective, the transistor Q2 and the transistor Q3 are switched on, the transistor Q1 and the transistor Q4 are switched off, the switch S1 is switched on, the switch S2 and the switch S3 are switched off, the coil, the transistor Q2, the transistor Q3, the switch S1 and the high-voltage DC form a loop, the current I in the coil gradually increases under the action of the high-voltage DC-DC, the current direction in the coil is reverse, and the amplitude of the current I meets the formula:
Figure BDA0002338794900000121
when t is t5, the current I is I2When the current reaches the condition of switchable emission current;
step 412, the main control module turns off the switch S1 through the first switch drive, turns on the switch S2 through the second switch drive, and turns off the switch S3 through the third switch drive, and at this time, the main DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t5, and it is ready to enter the current flat-top stage;
step 413, determining whether the PWMB is finished, if so, performing step 414, otherwise, repeating the step, and determining that the basis is the falling edge of the PWMB, which will be further described with reference to fig. 5:
in the time from t5 to t6, the PWMB signals of the transistor Q2 and the transistor Q3 are controlled to be effective, the signal of the control switch S2 is controlled to be effective, the PWMB signals of the transistor Q2 and the transistor Q3 are controlled, and the signals of the control switches S1 and S3 are controlled to be ineffective, at the moment, the transistor Q2 and the transistor Q3 are switched on, the transistor Q1 and the transistor Q4 are switched off, the switch S1 is switched off, the switch S2 is switched on, the switch S3 is switched off, a coil, the transistor Q2, the transistor Q3, the switch S2 and the main DC-DC form a loop, the current in the coil is kept stable under the action of the main DC-DC, and the emission current;
when t is t6, PWMB generates a falling edge, and the condition of PWMB ending is met;
step 414, the main control module turns off the switch S1 through the first switch drive, turns off the switch S2 through the second switch drive, and turns on the switch S3 through the third switch drive, and at this time, the clamp DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t6, and it is ready to enter the current fast turn-off stage;
step 415, determining whether the emission current of the negative half period is turned off, if so, performing step 416, otherwise, repeating the step, and determining that the current I is decreased to 0 according to the determination result, which will be further described with reference to fig. 5:
in the time period from t6 to t7, the signal for controlling the switch S3 is effective, the PWMA and PWMB signals for controlling the Q1 to Q4 and the signals for controlling the switch S1 and the switch S2 are ineffective, at the moment, the Q1 to Q4 are cut off, the switch S2 is cut off, the switch S3 is turned on, the switch S1 is cut off, the coil, the switch S3 and the clamp DC-DC form a loop, the coil discharges electricity through the loop, and the current in the coil is gradually reduced under the action of the clamp DC-DC;
when t is t7, the current in the coil is reduced to 0, and the condition that the emission current is turned off in the negative half period is met;
step 416, the main control module closes the switch S3 through the third switch drive, opens the switch S1 through the first switch drive, and opens the switch S2 through the second switch drive, and at this time, the high-voltage DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t7, and it is ready to enter the signal acquisition stage;
step 417, determining whether the signal acquisition is completed, if so, performing step 418, otherwise, repeating the step, and determining whether the transmission time T is equal to T, which is further described with reference to fig. 5:
in the time T7-T, signals of a control switch S1 are effective, PWMA and PWMB signals of control Q1-Q4 and signals of a control switch S2 and a switch S3 are ineffective, at the moment, Q1-Q4 are cut off, the switch S3 is cut off, the switch S1 is turned on, the switch S2 is cut off, and the system collects signals through a receiving coil;
step 418, referring to fig. 5, when T is equal to T, ending the signal acquisition of the receiving coil, ending the current emission of a single period, and performing step 305;
step 305, whether pulse transmission of Q periods is finished or not is judged, and if yes, the work is finished; otherwise, go to step 304;
examples
Step 301, after the instruments are connected, transmitting current I is input through an upper computer03A, the emission period number Q is 1, the excitation frequency f is 1000Hz, the emission current duty ratio D is 10%, and the emission current is turned off for a time toff5us, emission current size I0When the high-voltage DC-DC is switched to the main DC-DC, the scaling coefficient m of the current and the emission current is 90%, the required rise time accounts for the whole current emission time, and the scaling coefficient n is 10%, and the current and the emission current are transmitted to a master control system;
step 302, the main control system inputs parametersAnd adjusting the high voltage DC-DC value U by hardware parameters1Main DC-DC value U2And clamping the DC-DC value U3。
When the equivalent resistance R of the transmitting coilr0.2 Ω, equivalent inductance L of the transmitting coilr200uH, emission current period T1/f 1ms, emission current rise time TupnDT-10 us, positive half-cycle emission current I10＝I03A, negative half-cycle emission current I20＝-I03A, positive half-cycle switching current I1＝mI102.7A, negative half-cycle switching current I2＝mI20When the value is-2.7A, the high voltage DC-DC value can be obtained
Figure BDA0002338794900000141
Main DC-DC value U2＝RrI0Clamping DC-DC value of 0.6V
Figure BDA0002338794900000142
Step 303, continuously collecting the current of the transmitting coil by using a current sensor, and starting current detection on the main control through the current sensor;
at step 304, the transmit pulse is initiated. Referring to fig. 4, in a period T, a bipolar pulse transmission is performed, where T is an excitation pulse period, the H-bridge transmission module control signal is Q (PWMA, PWMB), the first switch 7 (switch S1) control signal is S1, the second switch 8 (switch S2) control signal is S2, and the third switch 9 (switch S3) control signal is S3, and the pulse transmission steps in a single period are as follows:
step 401, the main control module closes the switch S1 through the first switch drive, opens the switch S2 through the second switch drive, and opens the switch S3 through the third switch drive, at this time, the high voltage DC-DC is connected to the circuit to prepare for positive pulse emission;
step 402, starting the emission of the positive pulse, referring to fig. 5, when t is t1 is 0 and the current I is 0, and preparing to enter a current fast rising phase;
step 403, determining whether the current rises to the magnitude of the switchable emission current, if so, performing step 404, otherwise, repeating the step, and determining whether the amplitude of the current I reaches I1, which is further described with reference to fig. 5:
in the time from t1 to t2, the PWMA signals for controlling Q1 and Q4 are enabled, the signal for controlling the switch S1 is enabled, the PWMB signals for controlling Q2 and Q3 and the signals for controlling the switches S2 and S3 are disabled, at this time, Q1 and Q4 are turned on, Q2 and Q3 are turned off, the switch S1 is turned on, the switches S2 and S3 are turned off, the coil, Q1, Q4, S1 and high-voltage DC-DC form a loop, the current I in the coil is gradually increased under the action of the high-voltage DC-DC, the current direction in the coil is set as the positive direction at this time, and the amplitude of the current I meets the following conditions:
Figure BDA0002338794900000151
when t is t2 ≈ 9.04us, current I ═ I is satisfied1When the current reaches the condition of switchable emission current, 2.7A;
step 404, the main control module turns off the switch S1 through the first switch drive, turns on the switch S2 through the second switch drive, and turns off the switch S3 through the third switch drive, and at this time, the main DC-DC is connected to the circuit, and referring to fig. 5, at this time, t is t2 ≈ 9.04us, and it is ready to enter the current flat-top stage;
step 405, determining whether PWMA is finished, if yes, performing step 406, otherwise, repeatedly executing the step, and determining that the PWMA is a falling edge, which will be further described with reference to fig. 5:
in the time period from t2 to t3, the PWMA signal of the transistor Q1 and the transistor Q4 is controlled to be effective, the signal of the switch S2 is controlled to be effective, the PWMB signal of the transistor Q2 and the transistor Q3 is controlled, and the signals of the switch S1 and the switch S3 are controlled to be ineffective, at this time, the transistor Q1 and the transistor Q4 are switched on, the transistor Q2 and the transistor Q3 are switched off, the switch S1 is switched off, the switch S2 is switched on, the switch S3 is switched off, a coil, the transistor Q1, the transistor Q4, the switch S2 and the main DC-DC form a loop, the current in the coil is kept stable under the action of the main DC-DC, and the emission current,
when t3 is 100us, the PWMA generates a falling edge, and the condition of PWMA ending is met;
step 406, the main control module turns off the switch S1 through the first switch drive, turns off the switch S2 through the second switch drive, and turns on the switch S3 through the third switch drive, and at this time, the clamp DC-DC is connected to the circuit, and referring to fig. 5, at this time, t is t3 is 100us, and the current is ready to enter the current fast turn-off stage;
step 407, determining whether the emission current of the positive half period is turned off, if so, performing step 408, otherwise, repeating the step, and determining that the amplitude of the current I is reduced to 0 according to the determination. This step is further explained below with reference to fig. 5:
in the time period from t3 to t4, the signal for controlling the switch S3 is effective, the PWMA and PWMB signals for controlling the Q1 to Q4 and the signals for controlling the switch S1 and the switch S2 are ineffective, at the moment, the Q1 to Q4 are cut off, the switch S2 is cut off, the switch S3 is turned on, the switch S1 is cut off, the coil, the switch S3 and the clamp DC-DC form a loop, the coil discharges electricity through the loop, and the current in the coil is gradually reduced under the action of the clamp DC-DC;
when t is equal to t4 and t is equal to 105us, the current in the coil is reduced to 0, and the condition that the emission current is turned off in the positive half period is met;
step 408, the main control module closes the switch S3 through the third switch drive, opens the switch S1 through the first switch drive, and opens the switch S2 through the second switch drive, and at this time, the high-voltage DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t4 is 105us, and it is ready to enter the signal acquisition stage;
step 409, judging whether the signal acquisition is finished, if so, performing step 410, otherwise, repeating the step, and judging whether the emission time T is equal to T/2 according to the judgment basis. This step is further explained below with reference to fig. 5:
in the time T4-T/2, signals of a control switch S1 are effective, PWMA and PWMB signals of control Q1-Q4 and signals of a control switch S2 and a control switch S3 are ineffective, at the moment, Q1-Q4 are cut off, a switch S3 is cut off, a switch S1 is turned on, a switch S2 is cut off, and the system collects signals through a receiving coil;
when T/2 is 500us, the signal acquisition of the receiving coil is finished;
step 410, the main control module keeps the switch driving state unchanged, starts the emission of the negative pulse, and prepares to enter a current fast rising stage, referring to fig. 5, at this time, T/2 is 500 us;
step 411, determining whether the current rises to the magnitude of the switchable emission current, if so, performing step 412, otherwise, repeating the step, and determining whether the amplitude of the current I reaches I or not2This step is further explained below with reference to fig. 5:
in the time T/2-T5, the PWMB signal of the transistor Q2 and the transistor Q3 is controlled to be effective, the signal of the control switch S1 is controlled to be effective, the PWMA signal of the transistor Q1 and the transistor Q4 and the signals of the control switches S2 and S3 are controlled to be ineffective, the transistor Q2 and the transistor Q3 are switched on, the transistor Q1 and the transistor Q4 are switched off, the switch S1 is switched on, the switch S2 and the switch S3 are switched off, the coil, the transistor Q2, the transistors Q3, S1 and the high-voltage DC form a loop, the current I in the coil is gradually increased under the action of the high-voltage DC-DC, the current direction in the coil is reversed, and the amplitude of the current I meets the formula:
Figure BDA0002338794900000171
when t is t5 509.04us, the current I is I2-2.7A, when the current reaches the condition of switchable emission current magnitude;
step 412, the main control module turns off the switch S1 through the first switch drive, turns on the switch S2 through the second switch drive, and turns off the switch S3 through the third switch drive, and at this time, the main DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t5 is 509.04us, and it is ready to enter the current flat-top stage;
step 413, determining whether the PWMB is finished, if so, performing step 414, otherwise, repeating the step, and determining that the basis is the falling edge of the PWMB, which will be further described with reference to fig. 5:
in the time from t5 to t6, the PWMB signals of the transistor Q2 and the transistor Q3 are controlled to be effective, the signal of the switch S2 is controlled to be effective, the PWMB signals of the transistor Q2 and the transistor Q3 are controlled, and the signals of the switch S1 and the switch S3 are controlled to be ineffective, at this time, the transistor Q2 and the transistor Q3 are switched on, the transistor Q1 and the transistor Q4 are switched off, the switch S1 is switched off, the switch S2 is switched on, the switch S3 is switched off, a coil, the transistor Q2, the transistor Q3, the switch S2 and the main DC-DC form a loop, the current in the coil is kept stable under the action of the main DC-DC, and the emission current is;
when t6 is 600us, PWMB generates a falling edge, and the condition of PWMB ending is met;
step 414, the main control module turns off the switch S1 through the first switch drive, turns off the switch S2 through the second switch drive, and turns on the switch S3 through the third switch drive, and at this time, the clamp DC-DC is connected to the circuit, and referring to fig. 5, at this time, t is t6 is 600us, and the current is ready to enter the current fast turn-off stage;
step 415, determining whether the emission current of the negative half period is turned off, if so, performing step 416, otherwise, repeating the step, and determining that the amplitude of the current I is reduced to 0, which is further described with reference to fig. 5:
in the time period from t6 to t7, the signal for controlling the switch S3 is effective, the PWMA and PWMB signals for controlling the Q1 to Q4 and the signals for controlling the switch S1 and the switch S2 are ineffective, at the moment, the Q1 to Q4 are cut off, the switch S2 is cut off, the switch S3 is turned on, the switch S1 is cut off, the coil, the S3 and the clamp DC-DC form a loop, the coil discharges through the loop, and the current in the coil is gradually reduced under the action of the clamp DC-DC;
when t is t7 us, the current amplitude in the coil is reduced to 0, and the condition that the emission current is turned off in the negative half period is met;
step 416, the main control module closes the switch S3 through the third switch drive, opens the switch S1 through the first switch drive, and opens the switch S2 through the second switch drive, and at this time, the high-voltage DC-DC is connected to the circuit, referring to fig. 5, and at this time, t is t7 is 605us, and it is ready to enter the signal acquisition stage;
step 417, determining whether the signal acquisition is completed, if so, performing step 418, otherwise, repeating the step, and determining whether the transmission time T is equal to T, which is further described with reference to fig. 5:
in the time T7-T, signals of a control switch S1 are effective, PWMA and PWMB signals of control Q1-Q4 and signals of a control switch S2 and a switch S3 are ineffective, at the moment, Q1-Q4 are cut off, the switch S3 is cut off, the switch S1 is turned on, the switch S2 is cut off, and the system collects signals through a receiving coil;
step 418, referring to fig. 5, when T equals to 1ms, ending the signal acquisition of the receiving coil, ending the current emission of a single period, and performing step 305;
step 305, whether pulse emission of Q cycles is completed or not is judged, and if Q is equal to 1, the work is finished; otherwise, go to step 304.

Claims (6)

1. A towed electromagnetic survey apparatus for high quality transmit waveforms including a receiving system having a receiving coil and a transmitting system having a transmitting coil, the apparatus comprising: the high-voltage DC-DC power supply comprises a main control module, an upper computer, a power supply, a first switch driver, a second switch driver, a third switch driver, a first switch, a second switch, a third switch, a first protection diode, a second protection diode, a third protection diode, a high-voltage DC-DC, a main DC-DC, a clamping DC-DC, a PWM driver and an H-bridge emission module;
wherein, the upper computer transmits the parameters required by the system operation into the main control module and receives the data returned from the main control module,
the power supply is used for connecting through the main control module;
the first switch drive is used for driving a first switch, and the first switch is connected with the H-bridge transmitting module through a first protection diode and a high-voltage DC-DC;
the second switch drive is used for driving a second switch, and the second switch is connected with the H-bridge transmitting module through a second protection diode and a main DC-DC;
the third switch driver is used for driving a third switch, and the third switch is connected with the H-bridge emission module through a third protection diode and a clamping DC-DC;
the H-bridge emission module comprises a transistor Q1 and a transistor Q2 which are connected in series, a transistor Q3 and a transistor Q4 which are connected in series, one end of an emission coil is connected between the transistor Q1 and the transistor Q2, and the other end of the emission coil is connected between the transistor Q3 and the transistor Q4; the transistor Q1 and the transistor Q3 are connected to the first switch, the second switch and the third switch; the transistor Q2 and the transistor Q4 are respectively connected with the high-voltage DC-DC, the main DC-DC and the clamp DC-DC to form an H bridge;
the main control module controls the first switch to be switched on or switched off through the first switch drive, controls whether the high-voltage DC-DC is connected into a circuit or not, and supplies power to the transmitting system and guides the transmitting current to rapidly rise when the transmitting current reaches the stage of rapidly rising the current; the second switch is driven to be controlled to be switched on or switched off through the second switch, whether the main DC-DC is connected with a circuit or not is controlled, and power is supplied to the emission system when the emission current reaches the current flat top stage, so that the emission system emits stable current; the third switch is driven to be controlled to be switched on or switched off through the third switch, and whether the clamping DC-DC is connected into the circuit or not is controlled, so that voltage clamping is carried out at the current quick turn-off stage, and the emission current of the emission system is quickly turned off;
the main control module generates PWM signals with adjustable frequency and duty ratio, the H-bridge emission module is driven and controlled to work through the PWM signals, corresponding bipolar emission current is generated, and an excitation magnetic field is generated through the emission coil.
2. A method for towed electromagnetic surveying of high quality transmit waveforms, the method comprising: according to the emission time sequence, in a period T, bipolar pulse emission is carried out once, and when the emission current reaches the stage of rapid current rise, high-voltage power supply is carried out on an emission system, and the emission current is guided to rise rapidly;
when the emission current reaches the stage of current flat top, the main voltage of the emission system is supplied with power, so that the emission system emits stable current;
and voltage clamping is carried out at the stage of quickly turning off the emission current, so that the emission current of an emission system is quickly turned off.
3. The method according to claim 2, characterized in that in a single-cycle pulse transmission it comprises in particular:
step 401, a main control module closes a first switch through driving of the first switch, opens a second switch through driving of the second switch, opens a third switch through driving of the third switch, connects a high-voltage DC-DC into a circuit, and prepares for positive pulse emission;
step 402, starting the emission of positive pulses, wherein t is 0, and preparing to enter a current rapid rising stage;
step 403, determining whether the current rises to the magnitude of the switchable emission current, if so, performing step 404, otherwise, repeating the step, and determining whether the amplitude of the current I reaches the current I according to the determination result1；I1Switching the current for the positive half cycle;
step 404, the main control module switches off the first switch through the driving of the first switch, switches on the second switch through the driving of the second switch, switches off the switch through the driving of the third switch, connects the main DC-DC to the circuit, and enters a current flat stage;
step 405, determining whether the PWMA signal controlling the transistor Q1 and the transistor Q2 is finished, if yes, performing step 406, otherwise, repeatedly executing the step, and determining the result as the falling edge of the PWMA signal;
step 406, the main control module disconnects the first switch through the driving of the first switch, disconnects the second switch through the driving of the second switch, closes the third switch through the driving of the third switch, and at the moment, clamps the DC-DC connection circuit to prepare to enter a current rapid turn-off stage;
step 407, judging whether the emission current of the positive half period is turned off, if so, performing step 408, otherwise, repeating the step;
step 408, the main control module closes the third switch through the driving of the third switch, disconnects the first switch through the driving of the first switch, disconnects the second switch through the driving of the second switch, and at the moment, the high-voltage DC-DC is connected into the circuit to prepare for entering a signal acquisition stage;
step 409, judging whether the signal acquisition is finished, if so, performing step 410, otherwise, repeating the step, and judging whether the emission time T is equal to T/2 or not according to the judgment criterion;
step 410, the main control module keeps the switch driving state unchanged, starts the emission of the negative pulse and prepares to enter a current rapid rising stage;
step 411, determining whether the current rises to the magnitude of the switchable emission current, if so, proceeding toGo to step 412, otherwise repeat this step, determine if the current I amplitude reaches I2(ii) a Wherein, I2Switching the current for a negative half cycle;
step 412, the main control module disconnects the first switch through the driving of the first switch, closes the second switch through the driving of the second switch, and disconnects the third switch through the driving of the third switch, and at the moment, the main DC-DC is connected into the circuit to prepare for entering a current flat-top stage;
step 413, judging whether the PWMB signal for controlling the transistor Q3 and the transistor Q2 is finished, if so, executing step 414, otherwise, repeating the step and judging the signal as the falling edge of the PWMB signal;
step 414, the main control module disconnects the first switch through the first switch drive, disconnects the second switch S2 through the second switch drive, and closes the third switch through the third switch drive, and at this time, the clamp DC-DC is connected to the circuit to prepare for entering a current fast turn-off stage;
step 415, judging whether the emission current of the negative half period is turned off, if so, performing step 416, otherwise, repeating the step, and judging that the amplitude of the current I is reduced to 0 according to the judgment;
step 416, the main control module closes the third switch through the driving of the third switch, disconnects the first switch through the driving of the first switch, disconnects the second switch through the driving of the second switch, and at the moment, the high-voltage DC-DC is connected into the circuit to prepare for entering a signal acquisition stage;
step 417, judging whether the signal acquisition is finished, if so, performing step 418, otherwise, repeating the step, and judging whether the transmitting time T is equal to T or not;
and step 418, finishing the signal acquisition of the receiving coil and finishing the current emission of a single period.
4. Method according to claim 3, characterized in that the voltage value U of the high voltage DC-DC is1Voltage value U of main DC-DC2And clamping the voltage value U of the DC-DC3The following relationship is satisfied:
I10＝I0，I20＝-I0，I1＝mI10，I2＝mI20，tup＝nDT，
Figure FDA0002338794890000041
U2＝RrI0，
Figure FDA0002338794890000042
wherein R isrIs an equivalent resistance of the transmitting coil, LrIs equivalent inductance of a transmitting coil, f is transmitting current frequency, T is transmitting current period, T is 1/f, D is transmitting current duty ratio, T is equivalent inductance of a transmitting coilupTo emit the current rise time, toffFor emission current off-time, I0For the magnitude of the emission current, I10For emission of current for positive half-cycles, I20For emission of current in negative half-cycles, I1Switching the current for positive half-cycles2And m is a proportionality coefficient of the current and the emission current when the high-voltage DC-DC is switched to the main DC-DC, and n is a proportionality coefficient of the required rise time in the whole current emission time.
5. The method according to claim 4, wherein in step 403, the current I in the transmitting coil is gradually increased under the action of the high voltage DC-DC, and the current I in the coil is in a positive direction, and the magnitude of the current I satisfies:
Figure FDA0002338794890000043
6. the method of claim 4, wherein in step 411, the current I in the transmitting coil is gradually increased under the action of the high voltage DC-DC, and the current direction in the coil is reversed, and the magnitude of the current I satisfies the formula:
Figure FDA0002338794890000051
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117492099A (en) * 2024-01-02 2024-02-02 吉林大学 Urban underground space towed time-frequency combined electromagnetic detection system and method

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070285096A1 (en) * 2006-06-09 2007-12-13 Hitachi, Ltd. Double-tuned RF coil
CN105119588A (en) * 2015-09-14 2015-12-02 吉林大学 Pulse current transmission circuit adopting transient electromagnetic method
CN105576992A (en) * 2016-01-06 2016-05-11 吉林大学 Electromagnetic emission apparatus capable of realizing flat-top maintaining and current rapid drop and control method
CN105743385A (en) * 2016-04-26 2016-07-06 吉林大学 Current waveform shaping circuit for transient electromagnetic transmitter
CN206698031U (en) * 2017-03-28 2017-12-01 中国地质科学院地球物理地球化学勘查研究所 A kind of aviation transient electromagnetic method composite wave pulse current radiating circuit
CN107979300A (en) * 2016-10-19 2018-05-01 中国科学院电子学研究所 Big the magnetic moment transmitter and its method of generating current of the trapezoidal electric current of bipolarity

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070285096A1 (en) * 2006-06-09 2007-12-13 Hitachi, Ltd. Double-tuned RF coil
CN105119588A (en) * 2015-09-14 2015-12-02 吉林大学 Pulse current transmission circuit adopting transient electromagnetic method
CN105576992A (en) * 2016-01-06 2016-05-11 吉林大学 Electromagnetic emission apparatus capable of realizing flat-top maintaining and current rapid drop and control method
CN105743385A (en) * 2016-04-26 2016-07-06 吉林大学 Current waveform shaping circuit for transient electromagnetic transmitter
CN107979300A (en) * 2016-10-19 2018-05-01 中国科学院电子学研究所 Big the magnetic moment transmitter and its method of generating current of the trapezoidal electric current of bipolarity
CN206698031U (en) * 2017-03-28 2017-12-01 中国地质科学院地球物理地球化学勘查研究所 A kind of aviation transient electromagnetic method composite wave pulse current radiating circuit

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
刘丽华等: "有源恒压钳位瞬变电磁发射机技术", 《地球物理学进展》 *
黄江波等: "一种钳位电压源时域发射电路研究与设计", 《电子科技》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117492099A (en) * 2024-01-02 2024-02-02 吉林大学 Urban underground space towed time-frequency combined electromagnetic detection system and method
CN117492099B (en) * 2024-01-02 2024-04-19 吉林大学 Urban underground space towed time-frequency combined electromagnetic detection system and method

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