Underground pipeline path detection equipment

Abstract

The invention belongs to the technical field of pipeline detection, and particularly relates to underground pipeline path detection equipment which comprises a transmitting device and a receiving device. The transmitting device comprises a processing module, a full-bridge driving circuit and a booster circuit, the full-bridge driving circuit receives an SVPWM signal and rectifies the SVPWM signal into a sine wave signal, and the booster circuit boosts the sine wave signal to generate an output signal and couples the output signal to a pipeline to be detected; the receiving device detects the electromagnetic wave change of the to-be-detected pipeline and calculates the path and depth of the to-be-detected pipeline; the transmitting device further comprises a sampling circuit, the sampling circuit samples a current signal and a voltage signal of the output signal and outputs the current signal and the voltage signal to the processing module, and the processing module adjusts the SVPWM signal according to the current signal and the voltage signal of the output signal. The sampling circuit is arranged in the transmitting device to sample the current signal and the voltage signal of the output signal and feed back the current signal and the voltage signal to the processing module. And the processing module adjusts the SVPWM signal according to the feedback signals, so that the SVPWM signal is at the optimal output power.

Description

Technical Field

[0001] The present application relates to the technical field of underground pipeline detection, and in particular to an underground pipeline path detection device. Background Art

[0002] With the acceleration of urbanization, underground pipelines and cables (including power cables, communication optical cables, water supply pipelines, etc.) are increasingly used in urban construction. The underground environment is complex, with interference factors such as geological structure, groundwater system and existing building foundations. Pipeline laying is difficult to observe directly because it is buried deep underground, which brings great difficulties to maintenance and management. Traditional detection methods, such as detectors based on the principle of electromagnetic induction, have the problem of inaccurate positioning and are easily affected by surrounding metal facilities and geomagnetic changes, resulting in errors in detection results. In addition, the above-mentioned detectors are complicated to operate, and are time-consuming and labor-intensive in data collection, analysis and interpretation, and are difficult to meet the needs of modern pipeline management.

[0003] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0004] In view of at least one of the above technical problems, the present application provides an underground pipeline path detection device.

[0005] The present application provides an underground pipeline path detection device, including: a transmitting device and a receiving device;

[0006] The transmitting device includes: a processing module, a full-bridge driving circuit and a boost circuit, wherein the processing module is used to output an SVPWM signal, the full-bridge driving circuit receives the SVPWM signal and rectifies it into a sine wave signal, the boost circuit boosts the sine wave signal to generate an output signal, and couples the output signal to the pipeline to be tested;

[0007] The receiving device detects the change of electromagnetic waves of the pipeline to be tested and calculates the path and depth of the pipeline to be tested;

[0008] The transmitting device also includes: a sampling circuit, which samples the current signal and voltage signal of the output signal and outputs them to the processing module. The processing module adjusts the SVPWM signal according to the current signal and voltage signal of the output signal to make the SVPWM signal at the optimal output power.

[0009] One of the above technical solutions has at least one of the following advantages or beneficial effects: The present application sets a sampling circuit in the transmitting device to sample the current signal and the voltage signal of the output signal and feeds back to the processing module. The processing module adjusts the SVPWM signal according to these feedback signals so that the SVPWM signal is at the optimal output power. This closed-loop power control mechanism can ensure that the transmitting device always operates at the optimal power, avoiding the problem of inaccurate detection or energy waste caused by excessively high or low power.

[0010] In some possible implementations, the processing module includes: a PID modulation unit, a power factor calculation unit and a signal output unit, the PID modulation unit obtains the current of the output signal and modulates the current of the output signal into a target current, the PID modulation unit obtains the voltage of the output signal and modulates the voltage of the output signal into a target voltage; the power factor calculation unit calculates the power factor based on the target current and the target voltage; the signal output unit determines the optimal output power based on the power factor and outputs the SVPWM signal.

[0011] In some possible implementations, when the power factor is 1, the signal output unit calculates the target power according to the target current and the target voltage, and the target power is the optimal output power;

[0012] When the power factor is not 1, the signal output unit recalculates the output frequency and calculates the optimal output power based on the output frequency.

[0013] In some possible implementations, the PID modulation unit modulates the current and voltage of the output signal based on a PID algorithm.

[0014] In some possible implementations, the full-bridge drive circuit includes: a first drive circuit, a first rectifier circuit, a second drive circuit and a second rectifier circuit, the first end of the first drive circuit is connected to the processing module, the first end of the first rectifier circuit is connected to the second end of the first drive circuit, the second end of the first rectifier circuit is connected to the boost circuit, the first end of the second drive circuit is connected to the processing module, the first end of the second rectifier circuit is connected to the second end of the second drive circuit, and the second end of the second rectifier circuit is connected to the boost circuit.

[0015] In some possible implementations, the first driving circuit includes: a first field effect tube and a second field effect tube, the gate of the first field effect tube and the gate of the second field effect tube are connected to the processing module, the source of the first field effect tube and the drain of the second field effect tube are connected to the first rectifier circuit, the drain of the first field effect tube is connected to a 5V power supply, and the source of the second field effect tube is grounded;

[0016] The second driving circuit includes: a third field effect tube and a fourth field effect tube, the gate of the third field effect tube and the gate of the fourth field effect tube are connected to the processing module, the source of the third field effect tube and the drain of the fourth field effect tube are connected to the second rectifier circuit, the drain of the third field effect tube is connected to a 5V power supply, and the source of the fourth field effect tube is grounded.

[0017] In some possible implementations, the first rectifier circuit includes: a first inductor and a first capacitor, a first end of the first inductor is connected to a gate of the first field effect transistor and a gate of the second field effect transistor, a second end of the first inductor is connected to a boost circuit, a first end of the first capacitor is connected to a second end of the first inductor, and a second end of the first capacitor is grounded;

[0018] The second rectifier circuit includes: a second inductor and a second capacitor, the first end of the second inductor is connected to the gate of the third field effect tube and the gate of the fourth field effect tube, the second end of the second inductor is connected to the boost circuit, the first end of the second capacitor is connected to the second end of the second inductor, and the second end of the second capacitor is grounded.

[0019] In some possible implementations, the boost circuit includes: a booster and a sampling resistor, the booster is used to boost the sinusoidal wave signal by 8 times, one end of the booster is respectively connected to the first rectifier circuit and the second rectifier circuit, and the other end of the booster is coupled to the pipeline to be tested through the sampling resistor.

[0020] In some possible implementations, the sampling circuit includes: a first amplification circuit;

[0021] The first amplifier circuit includes: a first operational amplifier, a thirteenth resistor, a first resistor, a second resistor and a third resistor, wherein the first end of the first operational amplifier is connected to the first end of the sampling resistor through the thirteenth resistor, the second end of the first operational amplifier is connected to the second end of the sampling resistor through the first resistor, the third end of the first operational amplifier is connected to the second end of the first operational amplifier through the second resistor, the third end of the first operational amplifier is connected to the processing module, one end of the third resistor is connected to the first end of the first operational amplifier, and the other end of the third resistor is grounded.

[0022] In some possible implementations, the sampling circuit includes: a second amplification circuit;

[0023] The second amplifier circuit includes: a second operational amplifier, a tenth resistor, a ninth resistor, an eleventh resistor and a twelfth resistor, the first end of the second operational amplifier is connected to one end of the sampling resistor through the tenth resistor, the second end of the second operational amplifier is grounded through the ninth resistor, the third end of the second operational amplifier is connected to the second end of the second operational amplifier through the eleventh resistor, the third end of the second operational amplifier is connected to the processing module, one end of the twelfth resistor is connected to the first end of the second operational amplifier, and the other end of the twelfth resistor is grounded.

[0024] The present application is further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A diagram showing the use status of the underground pipeline path detection device provided in an embodiment of the present application;

[0027] Figure 2 for Figure 1 The schematic diagram of the structure of the launch device;

[0028] Figure 3 for Figure 2 The structural diagram of the processing module;

[0029] Figure 4 for Figure 1 The schematic diagram of the structure of the launch device;

[0030] Figure 5 for Figure 4 Circuit diagram of the transmitting device; DETAILED DESCRIPTION

[0031] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0032] Figure 1 A usage status diagram of the underground pipeline path detection device provided in an embodiment of the present application.

[0033] like Figure 1 As shown, this embodiment provides an underground pipeline path detection device, including: a transmitting device 100 and a receiving device 200. During operation, the transmitting device 100 is clamped on the pipeline to be detected, and the transmitting device 100 is started. The transmitting device 100 couples the output signal to the pipeline to be detected. On the ground, the receiving device 200 is held and walked. The receiving device 200 detects the change of the electromagnetic wave of the pipeline to be detected, and calculates the path and depth of the pipeline to be detected.

[0034] The specific structure of the underground pipeline path detection equipment is introduced below.

[0035] Figure 2 for Figure 1 Schematic diagram of the structure of the transmitting device 100.

[0036] like Figure 2 As shown, the transmitting device 100 includes: a processing module 110, a full-bridge driving circuit 120 and a boost circuit 130. The processing module 110 is used to output an SVPWM signal. The full-bridge driving circuit 120 receives the SVPWM signal and rectifies it into a sine wave signal. The boost circuit 130 boosts the sine wave signal to generate an output signal, and couples the output signal to the pipeline to be tested. The receiving device 200 detects the change of the electromagnetic wave of the pipeline to be tested, and calculates the path and depth of the pipeline to be tested. The transmitting device 100 also includes: a sampling circuit 140. The sampling circuit 140 samples the current signal and the voltage signal of the output signal and outputs them to the processing module 110. The processing module 110 adjusts the SVPWM signal according to the current signal and the voltage signal of the output signal, so that the SVPWM signal is at the optimal output power.

[0037] The present application sets a sampling circuit 140 in the transmitting device 100 to sample the current signal and the voltage signal of the output signal and feed it back to the processing module 110. The processing module 110 adjusts the SVPWM signal according to these feedback signals so that the SVPWM signal is at the optimal output power. This closed-loop power control mechanism can ensure that the transmitting device 100 always works at the optimal power, avoiding the problem of inaccurate detection or energy waste caused by too high or too low power.

[0038] In addition, since the pipeline to be detected is usually arranged at a depth of 5m to 10cm underground in the city or suburbs, the receiving device 200 located on the ground can only sense very weak electromagnetic changes. Therefore, in order to accurately detect the pipeline path and depth, the electromagnetic field characteristics generated by the transmitting device 100 to excite the pipeline must be obvious enough and the amplitude must be large enough. SVPWM modulation technology can generate arbitrary waveform signals, and has the advantages of wide modulation frequency range, accurate frequency, high efficiency, etc., and is very suitable as an excitation source for underground pipeline detectors. The basic principle of SVPWM modulation is the area equivalence principle, that is, when narrow pulses with equal impulses but different shapes are added to the inertial link, the effect is basically the same. In other words, through a series of narrow pulse signals with different shapes, the integrals of the corresponding time are equal (areas are equal), and the final effect is the same. Therefore, SVPWM is to input a pulse sequence with equal amplitude to equivalent sine wave, so the output high pulse time width basically changes in a sinusoidal law; specifically, the processing module 110 calculates the required sine wave and then calculates the modulation pulse width according to the area equivalence principle, thereby achieving the effect of digital modulation.

[0039] In this embodiment, the receiving device 200 may include but is not limited to: a sensor module. The sensor module uses three high-sensitivity resonant coils to form an antenna array, wherein one tangential antenna is used to locate the center position of the cable and perform trough measurement, and two normal antennas are used to calculate the cable depth and perform peak measurement. Through the above three antennas, the electromagnetic waves of the pipeline to be tested are received, and the signals are finally calculated to locate the pipeline position.

[0040] Figure 3 for Figure 2 Schematic diagram of the structure of the processing module 110.

[0041] like Figure 3 As shown, in some embodiments, the processing module 110 includes: a PID modulation unit 111, a power factor calculation unit 112 and a signal output unit 113, the PID modulation unit 111 obtains the current of the output signal and modulates the current of the output signal into a target current, the PID modulation unit 111 obtains the voltage of the output signal and modulates the voltage of the output signal into a target voltage; the power factor calculation unit 112 calculates the power factor according to the target current and the target voltage; the signal output unit 113 determines the optimal output power according to the power factor, and outputs the SVPWM signal.

[0042] The PID modulation unit 111 is connected to the sampling circuit 140, and is used to obtain the current and voltage of the output signal, and then modulate it into the target current and target voltage. It is worth noting that the PID modulation unit 111 modulates the current and voltage of the output signal based on the PID algorithm. Since pipeline detection usually requires outdoor operations, it is necessary to consider the energy consumption of the detection device, and for safety reasons, the voltage output by the transmitting device 100 cannot be too high to avoid safety accidents. Therefore, the transmitting device 100 uses a PID algorithm for constant output, limits the maximum output voltage to 40V (target voltage), and limits the maximum output current to 0.5A (target current).

[0043] Specifically, the output of the PID modulation unit 111 can be expressed as:

[0044] u(t)=Kp*e(t)+Ki*∫e(t)dt+Kd*de(t) / dt

[0045] Among them, u(t) is the output of the PID modulation unit 111, e(t) is the current error value, ∫e(t)dt is the integral of the error, de(t) / dt is the derivative (rate of change) of the error, Kp, Ki, and Kd are control parameters, which need to be adjusted according to the specific control system and control requirements.

[0046] In this PID algorithm, the proportional (P) part: This part generates a control output proportional to the error based on the current error value. The larger the proportional coefficient (Kp), the faster the controller responds to the error, but too large a proportional coefficient may cause the system to oscillate. The integral (I) part: This part takes into account the cumulative effect of the error and generates a control output by integrating the error. The integral coefficient (Ki) is used to adjust the size of the integral action. The integral action helps to eliminate the steady-state error of the system, but if the integral coefficient is not set properly, it may cause the system to respond too slowly or overshoot. The differential (D) part: This part generates a control output based on the rate of change of the error, that is, responds to the speed of change of the error. The differential coefficient (Kd) is used to adjust the size of the differential action. The differential action helps to predict the future trend of the error, thereby improving the stability and response speed of the system, but if the differential coefficient is not set properly, it may amplify the noise or cause system instability.

[0047] At the same time, due to the different types and lengths of cables and different load types, the output frequency is adjusted to achieve the best output power and the most suitable output frequency is selected according to the power factor to achieve the best energy transmission effect, thereby ensuring the safety of the device, accurate path detection, and reasonable power consumption.

[0048] When the power factor is 1, the signal output unit 113 calculates the target power according to the target current and the target voltage. The target power is the optimal output power. At this time, the optimal output power is 20W.

[0049] When the power factor is not 1, the signal output unit 113 recalculates the output frequency and calculates the optimal output power based on the output frequency.

[0050] For example, when the access cable length is 22000 meters and the transmission frequency is 512 Hz: the output voltage Vth=40V, the output frequency is F=512 Hz, the inductance of the transmitter 100 transformer is 0.0121H, the transmitter output impedance Zth=20+2pi*F*0.012120=20+j39Ω. The load impedance ZL=RL+JXL=20-j39Ω, the output power P=|Vth|^2*RL / (RL+Rth)^2=40^2 / (4*20)=20W, and the power factor Pf=COS(θV-θI)=1.

[0051] Because the power factor = 1, there is no need to adjust the output frequency. P = 20W is the optimal output power.

[0052] Among them, ZL is the load impedance, RL is the real part of the load impedance, ZXL is the imaginary part of the load impedance, Zth is the Thevenin impedance of the transmitter output port, Rth is the real part of the port impedance, Jth is the imaginary part of the port impedance, Vth is the output voltage, Pmax is the maximum power transmitted to the load, when the sum of the load impedance and the transmitter impedance is a pure real number, the load obtains the maximum transmission power. The imaginary part of the load impedance JXL must be equal to the conjugate complex number of the imaginary part of the Thevenin impedance J*th, that is: JXL = J*th = -Jth.

[0053] When the access cable length is 220 meters and the transmission frequency is 512 Hz: the output voltage Vth=40V, the output frequency is F=512 Hz, the transformer inductance of the transmitting device 100 is L=0.0121H, the transmitter output impedance Zth=20+j39Ω, the load impedance ZL=RL+JXL=0.02-j3.9e+3, and the output power S=|Vth|^2*ZL / (ZL+Zth)^2=40^2*(0.02-j3.88e+3) / (20+j39+2.02-j3.92e+3)^2=0.0047+0.4121i(W),

[0054] Active power = 0.0047W,

[0055] Power factor Pf=COS(θV-θI)=COS(arctan((-3.92e+3) / 20+0.02))=0.005. If the power factor is less than 1, the output frequency needs to be adjusted.

[0056] At this time, JXL=-j3.92E+03 can be calculated based on Pf, that is, JXL=1 / (2*π*F*C), and C=1 / 2*π*F*JXL=7.92e-08(F). To make the power factor 1, that is, Jth=-JXL=0, 2*π*F*L=1 / (2*π*F*C), F={1 / [(2*π)^2*C*L]}^0.5={1 / [(2*π)^2*7.92e-08*0.0121]}^0.5=5141.2hz.

[0057] Therefore, you only need to adjust the output frequency to 5141.2hz to achieve the optimal output power.

[0058] When the access cable length is 220 meters and the transmission frequency is adjusted to 5141.2 Hz: the output voltage Vth = 40V, the output frequency is F = 5141.2 Hz, the transmitter transformer inductance is 0.0121H, the transmitter output impedance Zth = 20 + j390Ω, the load impedance ZL = RL + JXL = 0.02 - j390Ω, the output power P = |Vth|^2*RL / (RL+Rth)^2 = 40^2*0.02 / (0.02+20)^2 = 0.0798W, and the power factor Pf = COS(θV-θI) = 1.

[0059] Because the power factor = 1, there is no need to adjust the output frequency. P = 0.0798W is the optimal output power.

[0060] Figure 4 for Figure 1 Schematic diagram of the structure of the launch device.

[0061] like Figure 4 As shown, in some embodiments, the full-bridge drive circuit 120 includes: a first drive circuit 121, a first rectifier circuit 122, a second drive circuit 123 and a second rectifier circuit 124, the first end of the first drive circuit 121 is connected to the processing module 110, the first end of the first rectifier circuit 122 is connected to the second end of the first drive circuit 121, the second end of the first rectifier circuit 122 is connected to the boost circuit 130, the first end of the second drive circuit 123 is connected to the processing module 110, the first end of the second rectifier circuit 124 is connected to the second end of the second drive circuit 123, and the second end of the second rectifier circuit 124 is connected to the boost circuit 130.

[0062] In the full-bridge drive circuit 120, the input of the SVPWM signal can be adjusted more flexibly by the processing module 110 controlling the first drive circuit 121 and the second drive circuit 123 respectively, thereby accurately controlling the characteristics of the rectified sinusoidal wave signal, such as amplitude, frequency, etc. In addition, the first rectifier circuit 122 and the second rectifier circuit 124 can convert the SVPWM signal output by the processing module 110 into a sinusoidal wave signal. This rectification method helps to convert the pulse width modulated signal into a sinusoidal wave form that is more suitable for transmission in underground pipeline path detection. The sinusoidal wave signal has better stability and anti-interference ability during transmission, can reduce signal distortion, and ensure the effective propagation of the signal in the complex electromagnetic environment underground.

[0063] Figure 5 for Figure 4 Circuit diagram of the transmitter.

[0064] like Figure 5As shown, in some embodiments, the first driving circuit 121 includes: a first field effect transistor Q1 and a second field effect transistor Q2, the gate of the first field effect transistor Q1 and the gate of the second field effect transistor Q2 are connected to the processing module 110, the source of the first field effect transistor Q1 and the drain of the second field effect transistor Q2 are connected to the first rectifier circuit 122, the drain of the first field effect transistor Q1 is connected to a 5V power supply, and the source of the second field effect transistor Q2 is grounded;

[0065] The second driving circuit 123 includes: a third field effect transistor Q3 and a fourth field effect transistor Q4, the gate of the third field effect transistor Q3 and the gate of the fourth field effect transistor Q4 are connected to the processing module 110, the source of the third field effect transistor Q3 and the drain of the fourth field effect transistor Q4 are connected to the second rectifier circuit 124, the drain of the third field effect transistor Q3 is connected to a 5V power supply, and the source of the fourth field effect transistor Q4 is grounded.

[0066] The processing module 110 controls the on and off states of the first field effect transistor Q1 , the second field effect transistor Q2 , the third field effect transistor Q3 and the fourth field effect transistor Q4 through the commonly connected gates, thereby accurately adjusting the signals input to the first and second rectifier circuits 124 .

[0067] The first rectifier circuit 122 includes: a first inductor L1 and a first capacitor C1, wherein a first end of the first inductor L1 is connected to a gate of the first field effect transistor Q1 and a gate of the second field effect transistor Q2, a second end of the first inductor L1 is connected to the boost circuit 130, a first end of the first capacitor C1 is connected to a second end of the first inductor L1, and a second end of the first capacitor C1 is grounded;

[0068] The second rectifier circuit 124 includes: a second inductor L2 and a second capacitor C2. The first end of the second inductor L2 is connected to the gate of the third field effect transistor Q3 and the gate of the fourth field effect transistor Q4. The second end of the second inductor L2 is connected to the boost circuit 130. The first end of the second capacitor C2 is connected to the second end of the second inductor L2. The second end of the second capacitor C2 is grounded.

[0069] The boost circuit 130 includes: a booster T1 and a sampling resistor R8. The booster T1 is used to boost the sine wave signal by 8 times. One end of the booster T1 is connected to the first rectifier circuit 122 and the second rectifier circuit 124 respectively, and the other end of the booster T1 is coupled to the pipeline to be tested through the sampling resistor R8.

[0070] The sampling circuit 140 includes: a first amplifying circuit 141;

[0071] The first amplifier circuit 141 includes: a first operational amplifier U1, a thirteenth resistor R13, a first resistor R1, a second resistor R2 and a third resistor R3, a first end of the first operational amplifier U1 is connected to a first end of a sampling resistor R8 through the thirteenth resistor R13, a second end of the first operational amplifier U1 is connected to a second end of the sampling resistor R8 through the first resistor R1, a third end of the first operational amplifier U1 is connected to a second end of the first operational amplifier U1 through the second resistor R2, a third end of the first operational amplifier U1 is connected to the processing module 110, one end of the third resistor R3 is connected to a first end of the first operational amplifier U1, and the other end of the third resistor R3 is grounded. The first amplifier circuit 141 can effectively suppress common-mode interference signals, and can improve signal quality in application scenarios such as underground pipeline path detection where a complex electromagnetic environment may exist.

[0072] The sampling circuit 140 includes: a second amplifying circuit 142;

[0073] The second amplifier circuit 142 includes: a second operational amplifier U2, a tenth resistor R10, a ninth resistor R9, an eleventh resistor R11, and a twelfth resistor R12, wherein the first end of the second operational amplifier U2 is connected to one end of the sampling resistor R8 through the tenth resistor R10, the second end of the second operational amplifier U2 is grounded through the ninth resistor R9, the third end of the second operational amplifier U2 is connected to the second end of the second operational amplifier U2 through the eleventh resistor R11, the third end of the second operational amplifier U2 is connected to the processing module 110, one end of the twelfth resistor R12 is connected to the first end of the second operational amplifier U2, and the other end of the twelfth resistor R12 is grounded. The second amplifier circuit 142 can effectively suppress common-mode interference signals, and can improve the quality of signals in application scenarios such as underground pipeline path detection where complex electromagnetic environments may exist.

[0074] In the description of the embodiments of the present application, unless otherwise specified, " / " means or, for example, A / B can mean A or B; "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0075] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0076] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0077] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0078] The above are only preferred embodiments of the present application, and do not constitute any formal limitation on the present application. Any technician familiar with the art can use the above disclosed methods and technical contents to make many possible changes and modifications to the technical solution of the present application without departing from the scope of the technical solution of the present application, or modify it into an equivalent embodiment of equivalent changes. Therefore, all equivalent changes made according to the shape, structure and principle of the present application without departing from the content of the technical solution of the present application should be included in the protection scope of the present application.

Claims

1. An underground pipeline path detection device, characterized in that: include: Transmitting device and receiving device; The transmitting device comprises: a processing module, a full-bridge driving circuit and a boost circuit, wherein the processing module is used to output an SVPWM signal, the full-bridge driving circuit receives the SVPWM signal and rectifies it into a sine wave signal, the boost circuit boosts the sine wave signal to generate an output signal, and couples the output signal to the pipeline to be tested; The receiving device detects the change of electromagnetic waves of the pipeline to be tested and calculates the path and depth of the pipeline to be tested; The transmitting device also includes: a sampling circuit, which samples the current signal and voltage signal of the output signal and outputs them to the processing module. The processing module adjusts the SVPWM signal according to the current signal and voltage signal of the output signal so that the SVPWM signal is at an optimal output power.

2. The underground pipeline path detection device according to claim 1, characterized in that: The processing module includes: a PID modulation unit, a power factor calculation unit and a signal output unit, the PID modulation unit obtains the current of the output signal and modulates the current of the output signal into a target current, the PID modulation unit obtains the voltage of the output signal and modulates the voltage of the output signal into a target voltage; the power factor calculation unit calculates the power factor according to the target current and the target voltage; the signal output unit determines the optimal output power according to the power factor and outputs the SVPWM signal.

3. The underground pipeline path detection device according to claim 2, characterized in that: When the power factor is 1, the signal output unit calculates the target power according to the target current and the target voltage, and the target power is the optimal output power; When the power factor is not 1, the signal output unit recalculates the output frequency and calculates the optimal output power based on the output frequency.

4. The underground pipeline path detection device according to claim 2, characterized in that: The PID modulation unit modulates the current and voltage of the output signal based on the PID algorithm.

5. The underground pipeline path detection device according to claim 1, characterized in that: The full-bridge drive circuit includes: a first drive circuit, a first rectifier circuit, a second drive circuit and a second rectifier circuit, wherein the first end of the first drive circuit is connected to the processing module, the first end of the first rectifier circuit is connected to the second end of the first drive circuit, the second end of the first rectifier circuit is connected to the boost circuit, the first end of the second drive circuit is connected to the processing module, the first end of the second rectifier circuit is connected to the second end of the second drive circuit, and the second end of the second rectifier circuit is connected to the boost circuit.

6. The underground pipeline path detection device according to claim 5, characterized in that: The first driving circuit comprises: a first field effect transistor and a second field effect transistor, the gate of the first field effect transistor and the gate of the second field effect transistor are connected to the processing module, the source of the first field effect transistor and the drain of the second field effect transistor are connected to the first rectifier circuit, the drain of the first field effect transistor is connected to a 5V power supply, and the source of the second field effect transistor is grounded; The second driving circuit includes: a third field effect transistor and a fourth field effect transistor, the gate of the third field effect transistor and the gate of the fourth field effect transistor are connected to the processing module, the source of the third field effect transistor and the drain of the fourth field effect transistor are connected to the second rectifier circuit, the drain of the third field effect transistor is connected to a 5V power supply, and the source of the fourth field effect transistor is grounded.

7. The underground pipeline path detection device according to claim 6, characterized in that: The first rectifier circuit includes: a first inductor and a first capacitor, wherein a first end of the first inductor is connected to a gate of the first field effect transistor and a gate of the second field effect transistor, a second end of the first inductor is connected to the boost circuit, a first end of the first capacitor is connected to a second end of the first inductor, and a second end of the first capacitor is grounded; The second rectifier circuit includes: a second inductor and a second capacitor, the first end of the second inductor is connected to the gate of the third field effect transistor and the gate of the fourth field effect transistor, the second end of the second inductor is connected to the boost circuit, the first end of the second capacitor is connected to the second end of the second inductor, and the second end of the second capacitor is grounded.

8. The underground pipeline path detection device according to claim 5, characterized in that: The boost circuit includes: a booster and a sampling resistor. The booster is used to boost the sinusoidal wave signal by 8 times. One end of the booster is respectively connected to the first rectifier circuit and the second rectifier circuit, and the other end of the booster is coupled to the pipeline to be tested through the sampling resistor.

9. The underground pipeline path detection device according to claim 8, characterized in that: The sampling circuit comprises: a first amplifying circuit; The first amplifier circuit includes: a first operational amplifier, a thirteenth resistor, a first resistor, a second resistor and a third resistor, wherein the first end of the first operational amplifier is connected to the first end of the sampling resistor through the thirteenth resistor, the second end of the first operational amplifier is connected to the second end of the sampling resistor through the first resistor, the third end of the first operational amplifier is connected to the second end of the first operational amplifier through the second resistor, the third end of the first operational amplifier is connected to the processing module, one end of the third resistor is connected to the first end of the first operational amplifier, and the other end of the third resistor is grounded.

10. The underground pipeline path detection device according to claim 8, characterized in that: The sampling circuit comprises: a second amplifying circuit; The second amplifier circuit includes: a second operational amplifier, a tenth resistor, a ninth resistor, an eleventh resistor and a twelfth resistor, the first end of the second operational amplifier is connected to one end of the sampling resistor through the tenth resistor, the second end of the second operational amplifier is grounded through the ninth resistor, the third end of the second operational amplifier is connected to the second end of the second operational amplifier through the eleventh resistor, the third end of the second operational amplifier is connected to the processing module, one end of the twelfth resistor is connected to the first end of the second operational amplifier, and the other end of the twelfth resistor is grounded.

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