A multifunctional cathodic protection data logger

Abstract

The present application relates to the field of pipeline cathodic protection, and particularly relates to a multifunctional cathodic protection data recorder, which comprises: a micro-signal amplification circuit connected with a test pile terminal of a cathodic protection test pile, an alternating current rectification filtering circuit connected with the test pile terminal, a direct current signal filtering circuit connected with the test pile terminal, an analog-digital conversion circuit connected with the micro-signal amplification circuit, the alternating current rectification filtering circuit and the direct current signal filtering circuit, a level conversion circuit connected with the analog-digital conversion circuit, an RS485 communication circuit connected with the test pile terminal of the cathodic protection test pile, a main processor circuit connected with the level conversion circuit, the RS485 communication circuit and the test pile terminal of the cathodic protection test pile, and the present application is suitable for various types of cathodic protection test piles, can reduce the measurement deviation caused by the insufficient professional ability of the field operators, and can reduce the number and working time of the field test staff, thereby saving a large amount of labor cost.

Description

Technical Field

[0001] This invention relates to the field of pipeline cathodic protection, and more specifically to a multifunctional cathodic protection data logger. Background Technology

[0002] Existing cathodic protection testing facilities and equipment (cathodic protection data loggers or intelligent test piles) provide test data formats including: on-state potential, off-state potential, AC voltage, AC / DC current density, etc.; some intelligent test piles also have functions such as collecting corrosion rate. The above data can be used to evaluate the cathodic protection effect and the degree of stray current interference. In fact, the management of cathodic protection system facilities requires more detailed test parameters for evaluation and management, including the test potential test data of the test piece, the operating parameters of the sacrificial anode, the operating parameters of the solid-state decoupler, and the effectiveness of the insulation joint, all of which require a series of test data for evaluation and management.

[0003] However, existing intelligent potential testing piles can only measure and upload data for one type of testing device, and cannot integrate and statistically analyze data from all types of testing devices. Current testing methods require constantly changing connection methods and connecting different equipment and facilities depending on the type of testing pile, and one person cannot complete all testing tasks. Moreover, the current manual data acquisition method requires a high level of professional skills from personnel, involves many measurement parameters, and has a relatively complex procedure. The measured parameters will have errors due to factors such as personnel operation and instrument accuracy. If the on-site operator's professional skills are insufficient, it will also cause measurement deviations. In addition, all existing manual measurement data must be manually recorded, entered into electronic documents, and then integrated and analyzed. Summary of the Invention

[0004] The present invention provides a multifunctional cathodic protection data logger to solve at least one of the above-mentioned technical problems.

[0005] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A multifunctional cathodic protection data logger, applicable to various types of cathodic protection test piles, including:

[0006] A micro-signal amplification circuit is connected to the test terminal of the cathodic protection test pile and is used to amplify the first analog signal to be tested transmitted from the test terminal to obtain the first analog amplified signal to be tested.

[0007] An AC rectifier and filter circuit is connected to the test pile terminal and is used to rectify and filter the second analog signal to be tested transmitted from the test pile terminal to obtain the second analog signal to be tested rectified and filtered.

[0008] A DC signal filtering circuit is connected to the test pile terminal and is used to filter the third analog quantity test signal transmitted from the test pile terminal to obtain the third analog quantity test filtered signal.

[0009] An analog-to-digital conversion circuit is connected to the micro-signal amplification circuit, the AC rectification and filtering circuit, and the DC signal filtering circuit, and is used to perform analog-to-digital conversion on the first analog quantity amplified signal to be tested, the second analog quantity rectified and filtered signal to be tested, and the third analog quantity filtered signal to be tested, respectively, to obtain a first digital signal, a second digital signal, and a third digital signal.

[0010] A level conversion circuit, connected to the analog-to-digital conversion circuit, is used to perform level conversion on the first digital signal, the second digital signal and the third digital signal respectively, to obtain a first digital level conversion signal, a second digital level conversion signal and a third digital level conversion signal;

[0011] An RS485 communication circuit is connected to the test pile terminal of the cathodic protection test pile, and is used to collect and transmit sensing data output by the corrosion rate sensor connected to the test pile terminal.

[0012] The main processor circuit, connected to the level conversion circuit, the RS485 communication circuit, and the test terminal of the cathodic protection test post, is used to process the first digital level conversion signal, the second digital level conversion signal, the third digital level conversion signal, and the sensor data to obtain cathodic protection data; it is also used to output a 3.3V SPI signal, which is converted into a 2.5V SPI signal by the level conversion circuit and then sent to the analog-to-digital conversion circuit to control the analog-to-digital conversion process of the analog-to-digital conversion circuit; it is also used to control the on / off state of the test terminal and identify the type of cathodic protection test post;

[0013] The TF card circuit is connected to the main processing circuit and is used to store the cathode protection data;

[0014] The power supply circuit is connected to the test pile terminals, the micro-signal amplification circuit, the AC rectification and filtering circuit, the analog-to-digital conversion circuit, the level conversion circuit, the RS485 communication circuit, the main processor circuit, and the TF card circuit, and is used to supply power to the test pile terminals, the micro-signal amplification circuit, the AC rectification and filtering circuit, the analog-to-digital conversion circuit, the level conversion circuit, the RS485 communication circuit, the main processor circuit, and the TF card circuit.

[0015] Based on the above technical solution, the present invention can be further improved as follows.

[0016] Furthermore, the power supply circuit includes:

[0017] Rechargeable lithium battery;

[0018] A charging circuit is connected to a 20V external power supply and the rechargeable lithium battery, used to convert the 20V voltage of the external power supply into an 8.4V voltage and to charge the rechargeable lithium battery.

[0019] A primary linear regulator circuit is connected to the rechargeable lithium battery and the charging circuit to linearly regulate the 8.4V voltage output by the charging circuit or the voltage output by the rechargeable lithium battery to obtain a 5V voltage.

[0020] A secondary linear regulator circuit, connected to the primary linear regulator circuit, is used to linearly regulate the 5V voltage output by the primary linear regulator circuit to obtain a 3.3V voltage.

[0021] A 5V controllable power supply circuit is connected to the first-stage linear voltage regulator circuit and the main processor circuit, and is used to convert the 5V voltage output by the first-stage linear voltage regulator circuit into a controllable 5V voltage under the control of the main processor circuit.

[0022] A 5V to isolated ±5V circuit is connected to the 5V controllable power supply circuit to convert the controllable 5V voltage into isolated -5V voltage and isolated +5V voltage.

[0023] A precision 2.5V voltage reference circuit is connected to the 5V to isolation ±5V circuit to convert the isolation +5V voltage into a 2.5V reference voltage.

[0024] A 5V to 2.5V circuit is connected to the 5V to isolation ±5V circuit to convert the isolation +5V voltage to +2.5V voltage.

[0025] A 2.5V to -2.5V circuit, connected to the 5V to 2.5V circuit, is used to convert the +2.5V voltage to a -2.5V voltage;

[0026] Specifically, the 3.3V voltage powers the test pile terminals, the analog-to-digital converter circuit, the level conversion circuit, the RS485 communication circuit, the TF card circuit, and the main processor circuit; the isolated -5V voltage and the isolated +5V voltage power the micro-signal amplifier circuit and the AC rectifier and filter circuit; the 2.5V reference voltage powers the analog-to-digital converter circuit; and the +2.5V voltage and the -2.5V voltage power the analog-to-digital converter circuit and the level conversion circuit.

[0027] Furthermore, the charging circuit uses a chip of model LTC4002ES8-8.4#PBF as the main chip; the first-stage linear regulator circuit uses a chip of model TPS5405DR as the main chip; the second-stage linear regulator circuit uses a chip of model TLV75733PDBVR as the main chip; the 5V controllable power supply circuit uses an N+P channel MOSFET of model NCE603S as the controllable element; the 5V to isolated ±5V circuit uses a chip of model WRA0505S-2WR2 as the main chip; the precision 2.5V voltage reference circuit uses a chip of model REF192GSZ as the main chip; the 5V to 2.5V circuit uses a chip of model TLV70225DBVR as the main chip; and the 2.5V to -2.5V circuit uses an operational amplifier of model OP07DD as the main chip.

[0028] Furthermore, the micro-signal amplification circuit uses a COS128U chip as the main control chip.

[0029] Furthermore, the AC rectifier and filter circuit uses an operational amplifier of model OP07DD as the main chip.

[0030] Furthermore, the DC signal filtering circuit includes a TVS diode, a common-mode rejection filter, and a two-stage RC filter connected in sequence.

[0031] Furthermore, the analog-to-digital conversion circuit uses an MS5198T chip as the main chip; the level conversion circuit uses a π131U61 chip as the main chip.

[0032] Furthermore, the RS485 communication circuit uses a MAX3485ESA chip as the main chip; the main processor circuit uses an STM32L072 chip as the main chip.

[0033] Furthermore, the TF card circuit is connected to the main processor circuit via an SPI interface.

[0034] Furthermore, the test terminal includes a relay and a transistor. The base of the transistor is connected to the main processor circuit, the emitter of the transistor is grounded, and the collector of the transistor is connected to the coil of the relay.

[0035] The beneficial effects of this invention are as follows: This multifunctional cathodic protection data logger can automatically identify the basic information and type of various types of test piles, such as ordinary potential test piles, inspection plate test piles, test piles with corrosion rate probes, sacrificial anode test piles, and solid-state decoupler test piles. It automatically measures and collects data for each type of test pile, enabling unified and professional testing and management of the entire cathodic protection system's auxiliary facilities. It identifies all existing types of test piles in the cathodic protection system, automatically collects and stores all parameters, and exports data using fixed professional management record forms. It categorizes and summarizes data, allowing for timely monitoring of the current operational status of cathodic protection auxiliary facilities and system operation. This facilitates timely repair and maintenance of problematic parts, providing strong support for the integrity of the pipeline corrosion protection system. Simultaneously, this invention reduces measurement deviations caused by insufficient professional skills of on-site operators. Baseline inspection personnel can complete the cathodic protection data collection work without dispatching separate professional technicians. Furthermore, this invention reduces the number of on-site testing personnel and their working hours. A single operation is sufficient to automatically collect all relevant data. The testing time can be appropriately selected based on importance and interference levels, allowing one person to complete the task, saving significant labor costs. Attached Figure Description

[0036] Figure 1 This is a block diagram of the internal circuit structure of a multifunctional cathodic protection data logger according to the present invention;

[0037] Figure 2 This is a block diagram of the power supply circuit.

[0038] Figure 3 The circuit diagram for the charging circuit;

[0039] Figure 4 This is the circuit schematic of a single-stage linear voltage regulator circuit.

[0040] Figure 5 This is the circuit schematic of a two-stage linear voltage regulator circuit.

[0041] Figure 6 The circuit diagram for a 5V controllable power supply circuit;

[0042] Figure 7 The circuit schematic for a 5V to isolated ±5V circuit;

[0043] Figure 8 The circuit schematic of a precision 2.5V voltage reference circuit;

[0044] Figure 9 The circuit diagram for a 5V to 2.5V converter;

[0045] Figure 10 The circuit diagram for a 2.5V to -2.5V converter;

[0046] Figure 11 This is the circuit schematic of a micro-signal amplifier circuit.

[0047] Figure 12 This is the circuit schematic of an AC rectifier and filter circuit.

[0048] Figure 13 This is the circuit schematic of a DC signal filtering circuit.

[0049] Figure 14 Circuit schematics for analog-to-digital conversion circuits and level conversion circuits;

[0050] Figure 15 This is the circuit schematic of an RS485 communication circuit.

[0051] Figure 16 The circuit schematic of the main processor circuit;

[0052] Figure 17 This is the circuit schematic of the TF card circuit.

[0053] Figure 18 This is a circuit diagram for testing the terminal block. Detailed Implementation

[0054] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0055] like Figure 1 As shown, a multifunctional cathodic protection data logger is applicable to various types of cathodic protection test posts, including:

[0056] A micro-signal amplification circuit is connected to the test terminal of the cathodic protection test pile and is used to amplify the first analog signal to be tested transmitted from the test terminal to obtain the first analog amplified signal to be tested.

[0057] An AC rectifier and filter circuit is connected to the test pile terminal and is used to rectify and filter the second analog signal to be tested transmitted from the test pile terminal to obtain the second analog signal to be tested rectified and filtered.

[0058] A DC signal filtering circuit is connected to the test pile terminal and is used to filter the third analog quantity test signal transmitted from the test pile terminal to obtain the third analog quantity test filtered signal.

[0059] An analog-to-digital conversion circuit is connected to the micro-signal amplification circuit, the AC rectification and filtering circuit, and the DC signal filtering circuit, and is used to perform analog-to-digital conversion on the first analog quantity amplified signal to be tested, the second analog quantity rectified and filtered signal to be tested, and the third analog quantity filtered signal to be tested, respectively, to obtain a first digital signal, a second digital signal, and a third digital signal.

[0060] A level conversion circuit, connected to the analog-to-digital conversion circuit, is used to perform level conversion on the first digital signal, the second digital signal and the third digital signal respectively, to obtain a first digital level conversion signal, a second digital level conversion signal and a third digital level conversion signal;

[0061] An RS485 communication circuit is connected to the test pile terminal of the cathodic protection test pile, and is used to collect and transmit sensing data output by the corrosion rate sensor connected to the test pile terminal.

[0062] The main processor circuit, connected to the level conversion circuit, the RS485 communication circuit, and the test terminal of the cathodic protection test post, is used to process the first digital level conversion signal, the second digital level conversion signal, the third digital level conversion signal, and the sensor data to obtain cathodic protection data; it is also used to output a 3.3V SPI signal, which is converted into a 2.5V SPI signal by the level conversion circuit and then sent to the analog-to-digital conversion circuit to control the analog-to-digital conversion process of the analog-to-digital conversion circuit; it is also used to control the on / off state of the test terminal and identify the type of cathodic protection test post;

[0063] The TF card circuit is connected to the main processing circuit and is used to store the cathode protection data;

[0064] The power supply circuit is connected to the test pile terminals, the micro-signal amplification circuit, the AC rectification and filtering circuit, the analog-to-digital conversion circuit, the level conversion circuit, the RS485 communication circuit, the main processor circuit, and the TF card circuit, and is used to supply power to the test pile terminals, the micro-signal amplification circuit, the AC rectification and filtering circuit, the analog-to-digital conversion circuit, the level conversion circuit, the RS485 communication circuit, the main processor circuit, and the TF card circuit.

[0065] The present invention provides a multifunctional cathodic protection data logger that can automatically identify the information and type of ordinary test piles, inspection plate test piles, test piles with corrosion rate probes, sacrificial anode test piles, insulating joint test piles, and solid decoupler test piles, and automatically collect and store all parameters, thereby realizing unified and standardized testing and management of cathodic protection facilities.

[0066] The circuits in the multifunctional cathodic protection data logger of the present invention will be described in detail below.

[0067] In this embodiment: as Figure 2 As shown, the power supply circuit includes:

[0068] Rechargeable lithium battery;

[0069] A charging circuit is connected to a 20V external power supply and the rechargeable lithium battery, used to convert the 20V voltage of the external power supply into an 8.4V voltage and to charge the rechargeable lithium battery.

[0070] A primary linear regulator circuit is connected to the rechargeable lithium battery and the charging circuit to linearly regulate the 8.4V voltage output by the charging circuit or the voltage output by the rechargeable lithium battery to obtain a 5V voltage.

[0071] A secondary linear regulator circuit, connected to the primary linear regulator circuit, is used to linearly regulate the 5V voltage output by the primary linear regulator circuit to obtain a 3.3V voltage.

[0072] A 5V controllable power supply circuit is connected to the first-stage linear voltage regulator circuit and the main processor circuit, and is used to convert the 5V voltage output by the first-stage linear voltage regulator circuit into a controllable 5V voltage under the control of the main processor circuit.

[0073] A 5V to isolated ±5V circuit is connected to the 5V controllable power supply circuit to convert the controllable 5V voltage into isolated -5V voltage and isolated +5V voltage.

[0074] A precision 2.5V voltage reference circuit is connected to the 5V to isolation ±5V circuit to convert the isolation +5V voltage into a 2.5V reference voltage.

[0075] A 5V to 2.5V circuit is connected to the 5V to isolation ±5V circuit to convert the isolation +5V voltage to +2.5V voltage.

[0076] A 2.5V to -2.5V circuit, connected to the 5V to 2.5V circuit, is used to convert the +2.5V voltage to a -2.5V voltage;

[0077] Specifically, the 3.3V voltage powers the test pile terminals, the analog-to-digital converter circuit, the level conversion circuit, the RS485 communication circuit, the TF card circuit, and the main processor circuit; the isolated -5V voltage and the isolated +5V voltage power the micro-signal amplifier circuit and the AC rectifier and filter circuit; the 2.5V reference voltage powers the analog-to-digital converter circuit; and the +2.5V voltage and the -2.5V voltage power the analog-to-digital converter circuit and the level conversion circuit.

[0078] In the power supply circuit: a 20V input is converted to an 8.4V output by the charging circuit to charge a 7.4V rechargeable lithium battery and power a primary linear regulator circuit. When not charging, the rechargeable lithium battery powers the primary linear regulator circuit, which outputs 5V. This 5V is then converted to 3.3V by a secondary linear regulator circuit, powering the main processor circuit. The 5V is then converted to a controllable 5V by a 5V controllable power supply circuit; the control signal for this control is issued by the main processor circuit. After measurement, the processor circuit sends a control signal to cut off the controllable 5V signal to reduce power consumption and enter a low-power sleep state. The controllable 5V is then converted to isolated ±5V by a 5V to ±5V circuit. The isolated +5V is converted to +2.5V by a 5V to 2.5V circuit. The isolated +5V is then converted to a 2.5V reference voltage by a precision 2.5V voltage reference circuit. The +2.5V power supply is then converted to -2.5V by a 2.5V to -2.5V circuit. The power supply circuit provides various power supplies to the main functional circuits.

[0079] Preferred, Figure 3 This is the circuit schematic of the charging circuit; the charging circuit uses a chip of model LTC4002ES8-8.4#PBF as the main chip; Figure 3 In this context, VBAT represents the connected rechargeable lithium battery.

[0080] Preferred, Figure 4 This is a circuit diagram of a first-stage linear voltage regulator circuit; the first-stage linear voltage regulator circuit uses a TPS5405DR chip as the main chip; Figure 4 In this context, VCC5V represents the 5V output voltage of the first-stage linear regulator circuit.

[0081] Preferred, Figure 5 This is a circuit diagram of a two-stage linear voltage regulator circuit; the two-stage linear voltage regulator circuit uses a TLV75733PDBVR chip as the main chip; Figure 5 In this context, D+3.3V represents the 3.3V output voltage of the two-stage linear regulator circuit.

[0082] Preferred, Figure 6 The circuit diagram is for a 5V controllable power supply circuit. The 5V controllable power supply circuit uses an N+P channel MOSFET of model NCE603S as the controllable element. The main function of the 5V controllable power supply circuit is to convert VCC5V into a controllable 5V voltage under the control signal PWR_AD issued by the main processor circuit. Figure 6 In this context, VCC-AD represents the controllable 5V voltage output by the 5V controllable power supply circuit.

[0083] Preferred, Figure 7 The circuit diagram is for a 5V to ±5V isolation circuit; the 5V to ±5V isolation circuit uses a chip of model WRA0505S-2WR2 as the main chip; Figure 7 In the diagram, ACC1_+5V represents the isolated +5V voltage output by the 5V to isolated ±5V circuit, and ACC1_-5V represents the isolated -5V voltage output by the 5V to isolated ±5V circuit.

[0084] Preferred, Figure 8 This is a circuit schematic of a precision 2.5V voltage reference circuit; the precision 2.5V voltage reference circuit uses a REF192GSZ chip as the main chip; Figure 8 In this context, AD1-REF represents the 2.5V reference voltage output by the precision 2.5V voltage reference circuit, which primarily provides an accurate reference for analog-to-digital conversion circuits.

[0085] Preferred, Figure 9 The circuit diagram is for a 5V to 2.5V converter; the 5V to 2.5V converter uses a TLV70225DBVR chip as the main chip. Figure 9 In the diagram, A1+2.5V represents the +2.5V voltage output by the 5V to 2.5V circuit.

[0086] In the power supply circuit of this invention: the rechargeable design makes it cheaper and easier to use; the isolated power supply design separates analog and digital grounds, making the signal less susceptible to interference; and the multi-stage linear voltage regulation design results in smaller ripple and more accurate measurement data.

[0087] Preferred, Figure 10 The circuit diagram is for a 2.5V to -2.5V converter; the 2.5V to -2.5V converter uses an operational amplifier of model OP07DD as the main chip. Figure 10 In this context, A1-2.5V represents the -2.5V voltage output by the 2.5V to -2.5V circuit.

[0088] In this embodiment, Figure 11This is a circuit schematic of a micro-signal amplifier circuit; the micro-signal amplifier circuit uses a COS128U chip as the main control chip. The main function of the micro-signal amplifier circuit is to amplify and filter the first analog signal to be measured; wherein, the first analog signal to be measured is a current signal, such as the FL+ and FL- signals in a solid-state decoupler.

[0089] In this embodiment, Figure 12 This is a circuit diagram of an AC rectifier and filter circuit; the AC rectifier and filter circuit uses an operational amplifier of model OP07DD as the main chip. The main function of the AC rectifier and filter circuit is to convert the second analog signal to be measured into a DC voltage signal; wherein, the second analog signal to be measured is an AC voltage signal, such as the AC voltage signal in an internal or external pipe.

[0090] In this embodiment, Figure 13 This is a circuit diagram of a DC signal filtering circuit. The DC signal filtering circuit includes a TVS diode SMBJ200CA, a common-mode rejection filter YLM7060-701T, and a two-stage RC filter connected in sequence. The main function of the DC signal filtering circuit is to filter the third analog quantity test signal; wherein, the third analog quantity test signal is a DC voltage signal, such as pipeline voltage, test segment potential, anode open-circuit voltage, etc.

[0091] In this embodiment, Figure 14 This is a circuit schematic diagram of an analog-to-digital converter and a level conversion circuit; the analog-to-digital converter uses an MS5198T chip as the main chip; the level conversion circuit uses a π131U61 chip as the main chip.

[0092] This invention uses a 24-bit high-precision analog-to-digital converter circuit and a precision 2.5V voltage reference, resulting in more accurate signal measurement.

[0093] Because the main processor circuit has a voltage level of 3.3V, while the digital signal converted by the analog-to-digital converter is at a voltage level of 2.5V, this invention requires a level conversion circuit to ensure that data can be transmitted normally between the analog-to-digital converter circuit and the main processor circuit.

[0094] In this embodiment, Figure 15 This is a circuit diagram of the RS485 communication circuit; the RS485 communication circuit uses a MAX3485ESA chip as the main chip. The main processor circuit collects data from corrosion rate sensors and other components connected to the test pile terminals via the RS485 communication circuit.

[0095] This invention uses an RS485 bus to connect to the corrosion rate sensor, making sensor expansion more convenient.

[0096] In this embodiment, Figure 16 The circuit schematic of the main processor circuit is shown below; the main processor circuit uses an STM32L072 chip as the main chip.

[0097] The main processor circuit interacts with the test pile terminals via the I2C interface to write data and automatically identify the type of test pile.

[0098] The main processor circuit converts its 3.3V SPI signal into a 2.5V SPI signal required by the analog-to-digital converter circuit through a level conversion circuit. This controls the analog-to-digital converter circuit to convert analog signals into digital signals, thereby completing the data acquisition of analog signals to be measured from internal and external pipes, inspection plates, references, sacrificial anodes, solid-state decouplers, etc.

[0099] The main processor circuit records the processed data to the TF card via the SPI interface, and the user can view the data through the TF card.

[0100] In this embodiment, Figure 17 This is a circuit diagram of the TF card circuit; the TF card circuit is connected to the main processor circuit via an SPI interface, and the connection line uses a 47K pull-up resistor. This invention uses a TF card to store data, and stores it in tabular format, making data export more convenient.

[0101] In this embodiment, Figure 18 This is a circuit diagram of the test terminal block; the test terminal block includes a relay RL1 and a transistor Q1. The base of transistor Q1 is connected to the main processor circuit, the emitter of transistor Q1 is grounded, and the collector of transistor Q1 is connected to the coil of relay RL1. Additionally, the test terminal block also includes an EEPROM chip AT24C02C.

[0102] The main processor circuit uses I / O control signals to control the switching of transistor Q1 inside the test terminal to connect and disconnect the pipes and inspection plates. The test terminal connects the analog signals to be measured (including the first, second, and third analog signals) from the internal and external pipes, inspection plates, reference, sacrificial anode, and solid-state decoupler to the micro-signal amplification circuit, AC rectification and filtering circuit, and DC signal filtering circuit of the multi-functional data logger via aviation connectors.

[0103] This invention provides automatic parameter identification, measurement, and data recording for all types of cathodic protection test posts (ordinary potential test posts, inspection plate test posts, test posts with corrosion rate probes, sacrificial anode test posts, and solid-state decoupler test posts). It is applicable to the testing, operation, maintenance, and management of cathodic protection systems for all buried metal pipelines or other metal structures. It requires minimal expertise from testing personnel; simply plug in the test wiring for automatic identification and measurement, reducing the number of operators and measurement time, and significantly improving the efficiency of cathodic protection maintenance. It is an essential testing tool for cathodic protection testing and operation management personnel.

[0104] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multifunctional cathodic protection data logger, characterized in that, The cathode protection test pile is suitable for various types of cathode protection test piles, including: A micro-signal amplification circuit is connected with a test pile terminal of the cathode protection test pile, and is used for amplifying a first analog quantity to-be-tested signal transmitted by the test pile terminal to obtain a first analog quantity to-be-tested amplified signal; An alternating current rectification filtering circuit is connected with the test pile terminal, and is used for rectifying and filtering a second analog quantity to-be-tested signal transmitted by the test pile terminal to obtain a second analog quantity to-be-tested rectification filtering signal; A direct current signal filtering circuit is connected with the test pile terminal, and is used for filtering a third analog quantity to-be-tested signal transmitted by the test pile terminal to obtain a third analog quantity to-be-tested filtering signal; An analog-digital conversion circuit is connected with the micro-signal amplification circuit, the alternating current rectification filtering circuit and the direct current signal filtering circuit, and is used for respectively converting the first analog quantity to-be-tested amplified signal, the second analog quantity to-be-tested rectification filtering signal and the third analog quantity to-be-tested filtering signal into a first digital signal, a second digital signal and a third digital signal; A level conversion circuit is connected with the analog-digital conversion circuit, and is used for respectively converting the first digital signal, the second digital signal and the third digital signal into a first digital level conversion signal, a second digital level conversion signal and a third digital level conversion signal; An RS485 communication circuit is connected with the test pile terminal of the cathode protection test pile, and is used for collecting and transmitting sensing data output by a corrosion rate sensor connected with the test pile terminal; A main processor circuit is connected with the level conversion circuit, the RS485 communication circuit and the test pile terminal of the cathode protection test pile, and is used for processing the first digital level conversion signal, the second digital level conversion signal, the third digital level conversion signal and the sensing data to obtain cathode protection data; is further used for outputting a 3.3V SPI signal, and transmitting the 2.5V SPI signal converted by the level conversion circuit to the analog-digital conversion circuit to control the analog-digital conversion process of the analog-digital conversion circuit; is further used for controlling the on-off of the test pile terminal and identifying the type of the cathode protection test pile; A TF card circuit is connected with the main processing circuit, and is used for storing the cathode protection data; A power supply circuit is connected with the test pile terminal, the micro-signal amplification circuit, the alternating current rectification filtering circuit, the analog-digital conversion circuit, the level conversion circuit, the RS485 communication circuit, the main processor circuit and the TF card circuit, and is used for supplying power for the test pile terminal, the micro-signal amplification circuit, the alternating current rectification filtering circuit, the analog-digital conversion circuit, the level conversion circuit, the RS485 communication circuit, the main processor circuit and the TF card circuit.

2. The multi-functional cathodic protection data logger of claim 1, wherein, The power supply circuit includes: A rechargeable lithium battery. A charging circuit is connected with the 20V external power supply and the rechargeable lithium battery, and is used to convert the 20V voltage of the external power supply into 8.4V voltage and charge the rechargeable lithium battery; A first linear voltage stabilizing circuit is connected with the rechargeable lithium battery and the charging circuit, and is used to linearly stabilize the 8.4V voltage output by the charging circuit or the voltage output by the rechargeable lithium battery to obtain 5V voltage; A second linear voltage stabilizing circuit is connected with the first linear voltage stabilizing circuit, and is used to linearly stabilize the 5V voltage output by the first linear voltage stabilizing circuit to obtain 3.3V voltage; A 5V controllable power supply circuit is connected with the first linear voltage stabilizing circuit and the main processor circuit, and is used to convert the 5V voltage output by the first linear voltage stabilizing circuit into controllable 5V voltage under the control of the main processor circuit; A 5V to isolation ±5V circuit is connected with the 5V controllable power supply circuit, and is used to convert the controllable 5V voltage into isolation-5V voltage and isolation+5V voltage; A precise 2.5V voltage reference circuit is connected with the 5V to isolation ±5V circuit, and is used to convert the isolation+5V voltage into 2.5V reference voltage; A 5V to 2.5V circuit is connected with the 5V to isolation ±5V circuit, and is used to convert the isolation+5V voltage into +2.5V voltage; A 2.5V to-2.5V circuit is connected with the 5V to 2.5V circuit, and is used to convert the +2.5V voltage into-2.5V voltage; The 3.3V voltage is used to supply power for the test pile terminal, the analog-digital conversion circuit, the level conversion circuit, the RS485 communication circuit, the TF card circuit and the main processor circuit; the isolation-5V voltage and the isolation+5V voltage are used to supply power for the micro-signal amplification circuit and the alternating current rectification filtering circuit; the 2.5V reference voltage is used to supply power for the analog-digital conversion circuit; and the +2.5V voltage and the-2.5V voltage are used to supply power for the analog-digital conversion circuit and the level conversion circuit.

3. The multifunctional cathodic protection data logger of claim 2, wherein, The charging circuit adopts a chip with model number LTC4002ES8-8.4#PBF as a main chip; the first linear voltage stabilizing circuit adopts a chip with model number TPS5405DR as a main chip; the second linear voltage stabilizing circuit adopts a chip with model number TLV75733PDBVR as a main chip; the 5V controllable power supply circuit adopts an N+P channel MOS tube with model number NCE603S as a controllable element; the 5V to isolation ±5V circuit adopts a chip with model number WRA0505S-2WR2 as a main chip; the precise 2.5V voltage reference circuit adopts a chip with model number REF192GSZ as a main chip; the 5V to 2.5V circuit adopts a chip with model number TLV70225DBVR as a main chip; and the 2.5V to-2.5V circuit adopts an operational amplifier with model number OP07DD as a main chip.

4. The multifunctional cathodic protection data logger of claim 1, wherein, The micro-signal amplification circuit adopts a chip with model number COS128U as a main control chip.

5. The multifunctional cathodic protection data logger of claim 1, wherein, The alternating current rectification filter circuit adopts an operational amplifier with a model number OP07DD as a main chip.

6. The multifunctional cathodic protection data logger of claim 1, wherein, The direct current signal filter circuit comprises a TVS tube, a common mode rejection filter and a two-stage RC filter connected in sequence.

7. The multifunctional cathodic protection data logger of claim 1, wherein, The analog-digital conversion circuit adopts a chip with a model number MS5198T as a main chip; and the level conversion circuit adopts a chip with a model number π131U61 as a main chip.

8. The multifunctional cathodic protection data logger of claim 1, wherein, The RS485 communication circuit adopts a chip with a model number MAX3485ESA as a main chip; and the main processor circuit adopts a chip with a model number STM32L072 as a main chip.

9. The multifunctional cathodic protection data logger of claim 1, wherein, The TF card circuit is connected with the main processor circuit through an SPI interface.

10. The multifunctional cathodic protection data logger of claim 1, wherein, The test pile terminal comprises a relay and a triode, a base of the triode is connected with the main processor circuit, an emitter of the triode is grounded, and a collector of the triode is connected with a coil of the relay.

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