A calibration-free and maintenance-free zirconium oxide analyzer

Abstract

A kind of calibration-free, maintenance-free zirconium oxide analyzer, including outer sleeve, fixed flange, zirconium oxide sensor, electric heater, temperature sensor, internal resistance test module, background potential test module, zirconium oxide analyzer out-of-tolerance test module and oxygen measurement calculation control module, fixed flange is sealingly fixed and installed at the end of outer sleeve, zirconium oxide sensor is coaxially arranged in outer sleeve and sealingly fixedly connected in the middle of inner end of fixed flange, electric heater is coaxially arranged between zirconium oxide sensor and outer sleeve and fixedly connected on the inner wall of outer sleeve end, temperature sensor is arranged in the inner end of zirconium oxide sensor.The present application can determine whether zirconium oxide analyzer is accurate in whole life cycle without calibration and maintenance, solve the problem that current zirconium oxide analyzer needs frequent calibration, reduce maintenance cost, and is maintenance-free in whole life cycle of zirconium oxide analyzer.

Description

Technical Field

[0001] This invention relates to the field of zirconia oxygen analysis instruments, specifically to a zirconia analyzer that is calibration-free and maintenance-free. Background Technology

[0002] Zirconia analyzers are widely used for oxygen detection in industrial combustion reaction processes and environmental monitoring of flue gas emissions. However, zirconia analyzers require frequent calibration with standard oxygen, sometimes even every two weeks, resulting in a particularly large workload for maintenance.

[0003] Therefore, we propose a calibration-free and maintenance-free zirconia analyzer. Summary of the Invention

[0004] The purpose of this invention is to provide a zirconia analyzer that is calibration-free and maintenance-free. This invention can determine the accuracy of the zirconia analyzer throughout its entire life cycle without calibration or maintenance, solving the problem of frequent calibration of zirconia analyzers, reducing maintenance costs, and eliminating the need for maintenance throughout the entire life cycle of the zirconia analyzer.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A calibration-free and maintenance-free zirconia analyzer includes an outer tube, a fixed flange, a zirconia sensor, an electric heater, a temperature sensor, an internal resistance testing module, a background potential testing module, a zirconia analyzer out-of-tolerance testing module, and an oxygen measurement and calculation control module. The fixed flange is sealed and fixedly installed at the end of the outer tube. The zirconia sensor is coaxially disposed inside the outer tube and sealed and fixedly connected to the middle of the inner end of the fixed flange. The electric heater is coaxially disposed between the zirconia sensor and the outer tube and fixedly connected to the inner wall of the end of the outer tube. The temperature sensor is disposed inside the zirconia sensor.

[0007] The internal resistance testing module is divided into a first internal resistance testing module and a second internal resistance testing module.

[0008] The first internal resistance test module, the second internal resistance test module, the background potential test module, the zirconia analyzer out-of-tolerance test module, and the oxygen measurement and calculation control module are all composed of electronic circuit boards;

[0009] The temperature sensor transmits its signal to the first internal resistance test module via the first signal line. The zirconia sensor transmits its signal to the second internal resistance test module via the second signal line. The electric heater is connected to the oxygen measurement and calculation control module via a control line. The second internal resistance test module transmits its signal to the background potential test module via the third signal line. The second internal resistance test module is connected to the zirconia analyzer out-of-tolerance test module via the fifth signal line. The first internal resistance test module is connected to the zirconia analyzer out-of-tolerance test module via the sixth signal line. The zirconia analyzer out-of-tolerance test module is connected to the oxygen measurement and calculation control module via the eighth signal line. The background potential test module is connected to the zirconia analyzer out-of-tolerance test module via the ninth signal line. The zirconia analyzer out-of-tolerance test module is connected to the out-of-tolerance alarm via the tenth signal line. The zirconia analyzer out-of-tolerance test module receives an external command to start the internal resistance test via the eleventh signal line. The zirconia analyzer out-of-tolerance test module receives a signal indicating permission to test the zirconia sensor background potential via the twelfth signal line. The zirconia analyzer out-of-tolerance test module contains a timing calculation block.

[0010] The first internal resistance testing module measured the resistance of the temperature sensor as follows: R T The second internal resistance testing module measured the internal resistance of the zirconia sensor to be... Ro The background potential test module measured the background potential of the zirconia sensor to be: E 0;

[0011] The out-of-tolerance logic operation of the out-of-tolerance test module of the zirconia analyzer is as follows:

[0012] If any of the following conditions are met, the zirconia analyzer will be considered out of tolerance, and the out-of-tolerance test module will issue an out-of-tolerance alarm:

[0013] ① Internal resistance of the zirconium oxide sensor Ro ≥a, where a is the probe internal resistance limit of the zirconia sensor that does not exceed the tolerance;

[0014] ② Absolute value of the resistance change of the temperature sensor | R T - R T0 |≥η, R T0 η is the initial value of the internal resistance of the temperature sensor, and η is the resistance variation limit of the temperature sensor that does not exceed the tolerance.

[0015] ③ Absolute value of the background potential change of the zirconia sensor | E 0- E 00 |≥θ, E 00θ is the initial value of the zirconia sensor's base potential, and θ is the allowable drift value of the zirconia sensor's base potential within tolerance.

[0016] a, R T0 ,η, E 00 θ is stored in the memory inside the out-of-tolerance test module of the zirconia analyzer.

[0017] The background potential testing module transmits the voltage value of the zirconia sensor measured via the ninth signal line to the zirconia analyzer's out-of-tolerance testing module. After receiving the signal allowing testing of the zirconia sensor's background potential via the twelfth signal line, the zirconia analyzer's out-of-tolerance testing module performs calculations and then uses the voltage value of the zirconia sensor received via the ninth signal line as the background electromotive force of the zirconia. E 0. The background potential test module also transmits the voltage value of the tested zirconium oxide sensor to the oxygen measurement and calculation control module through the twenty-third signal line.

[0018] The oxygen measurement and calculation control module receives the background potential of the zirconium oxide sensor measured by the background potential testing module. E 0 performs oxygen content calculation to determine the oxygen content P of the measured gas. The oxygen content calculation formula is:

[0019] ;

[0020] in, E The concentration cell potential is given in mV. k For coefficients; P 0 represents the oxygen content in the air (%), and P represents the oxygen content in the gas being measured (%). E 0 represents the background potential of the zirconia sensor measured by the background potential testing module, in mV.

[0021] The internal circuit structure of the first internal resistance test module includes a first relay and a first resistance test block. Both the first relay and the first resistance test block are connected to the zirconia analyzer out-of-tolerance test module via the sixth signal line. The common terminal of the first contact of the first relay is connected to the positive signal input line of the temperature sensor. The normally closed terminal of the first contact of the first relay is connected to the positive signal output line of the temperature sensor of the internal resistance test module. The normally open contact of the first contact of the first relay is connected to the first resistance test block via the twenty-first signal line. The common terminal of the second contact of the first relay is connected to the negative signal input line of the temperature sensor. The normally closed terminal of the second contact of the first relay is connected to the negative signal output line of the temperature sensor of the first internal resistance test module. The normally open contact of the second contact of the first relay is connected to the first resistance test block via the twenty-second signal line. After the first relay and the first resistance test block receive the start internal resistance test command sent by the zirconia analyzer out-of-tolerance test module via the sixth signal line, the first relay is activated. The common terminal of the first and second contact of the first relay is connected to its normally open contact. The positive signal input line and negative signal input line of the temperature sensor are respectively connected to the twenty-first signal line and the twenty-second signal line and connected to the first resistance test block. The first resistance test block tests the resistance between the positive signal input line and the negative signal input line of the temperature sensor. The first resistance test block sends the test result to the zirconia analyzer out-of-tolerance test module via the sixth signal line.

[0022] After the first relay and the first resistance test block receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the sixth signal line, the first relay returns to its original state, the common terminal of the first and second contact points of the first relay is connected to its normally closed terminal, the positive signal input line and negative signal input line of the temperature sensor are connected to the positive signal output line and negative signal output line of the temperature sensor respectively, and the common terminal of the first and second contact points of the first relay is disconnected from its normally open contact.

[0023] The internal circuit structure of the second internal resistance test module includes a second relay and a second resistance test block. Both the second relay and the second resistance test block are connected to the zirconia analyzer out-of-tolerance test module via the fifth signal line. The common terminal of the first contact of the second relay is connected to the positive signal input line of the zirconia sensor, and the normally closed terminal of the first contact of the second relay is connected to the positive signal output line of the zirconia sensor in the second internal resistance test module. The normally open contact of the second contact of the second relay is connected to the second resistance test block via the twenty-fifth signal line. The common terminal of the second contact of the second relay is connected to the negative signal input line of the zirconia sensor, and the normally closed terminal of the second contact of the second relay is connected to the negative signal output line of the zirconia sensor in the second internal resistance test module. The normally open contact of the second contact of the second relay is connected to the second resistance test block via the twenty-sixth signal line.

[0024] After receiving the start internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the fifth signal line, the second relay activates, and the common terminal of the first and second contact points of the second relay is connected to its normally open contact. The positive signal input line and negative signal input line of the zirconia sensor are respectively connected to the twenty-fifth and twenty-sixth signal lines and connected to the second resistance test block. The second resistance test block tests the resistance between the positive signal input line and the negative signal input line of the zirconia sensor and sends the test result to the zirconia analyzer out-of-tolerance test module through the fifth signal line.

[0025] After the second relay and the second resistance test block receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the fifth signal line, the second relay returns to its original state, and the common terminal of the first and second contact points of the second relay is connected to its normally closed terminal. The positive signal input line and negative signal input line of the zirconia sensor are connected to the positive signal output line and negative signal output line of the zirconia sensor, respectively. The common terminal of the first and second contact points of the second relay is disconnected from its normally open contact.

[0026] The signal output line of the first internal resistance test module is connected to the seventh signal line, which transmits the signal from the temperature sensor to the oxygen measurement and calculation control module. The signal output line of the second internal resistance test module is connected to the fourth signal line, which transmits the signal from the zirconium oxide sensor to the oxygen measurement and calculation control module.

[0027] The internal circuit structure of the first internal resistance testing module includes a first standard resistor, a first relay, a voltage testing block, and a first internal resistance calculation block. The first relay, voltage testing block, and first internal resistance calculation block are all connected to the zirconia analyzer's out-of-tolerance testing module via the sixth signal line. The positive and negative signal input lines of the temperature sensor are respectively connected to the normally open contacts of the two terminals of the first relay. The common terminal of the two terminals of the first relay is connected to both ends of the first standard resistor. The positive and negative signal input lines of the normally open contact temperature sensor are also connected to the voltage testing block via the eighteenth signal line. The voltage testing block transmits the measured voltage value signal from the temperature sensor via the fifteenth signal line. U T0 The signal is transmitted to the first internal resistance calculation block, and the voltage test block transmits the measured voltage value signal from the temperature sensor via the twenty-fourth signal line. U Tb The data is transmitted to the oxygen measurement and calculation control module. The first internal resistance calculation block transmits the measured resistance value of the temperature sensor to the 27th signal line. R T Oxygen measurement, calculation, and control module;

[0028] After receiving the start internal resistance test command from the zirconia analyzer's out-of-tolerance test module via the sixth signal line, the first relay, voltage test block, and first internal resistance calculation block connect the common terminal of the two contact points of the first relay to its normally open contact. The two ends of the first standard resistor are connected to the positive and negative signal input lines of the temperature sensor, respectively. The voltage test block then transmits the measured voltage signal. U Tb The signal is transmitted to the first internal resistance calculation block via the fifteenth signal line. The first internal resistance calculation block calculates the resistance between the positive and negative signal input lines of the temperature sensor using the following formula. R T Perform the calculation:

[0029] ;

[0030] Among them, R Tb This is the resistance value of the first standard resistor; U T0 The voltage value measured in the voltage test block before receiving the start internal resistance test command; U Tb The voltage value measured by the voltage test block after receiving the start internal resistance test command;

[0031] The first internal resistance calculation block transmits the calculation results to the zirconia analyzer out-of-tolerance test module via the sixth signal line;

[0032] After the first relay, voltage test block, and first internal resistance calculation block receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the seventh signal line, the common terminal of the two connection points of the first relay is disconnected from its normally open contact, and the two ends of the first standard resistor are disconnected from the positive signal input line and negative signal input line of the temperature sensor, respectively.

[0033] The internal circuit structure of the second internal resistance testing module includes a second relay, a second internal resistance calculation block, and a second standard resistor. Both the second relay and the second internal resistance calculation block are connected to the zirconia analyzer's out-of-tolerance testing module via the fifth signal line. The positive and negative signal input lines of the zirconia sensor are connected to the normally open contacts of the two terminals of the second relay, respectively. The common terminal of the two terminals of the second relay is connected to both ends of the second standard resistor. The positive and negative signal input lines of the zirconia sensor are also connected to the background potential testing module via the third signal line. The background potential testing module transmits the measured voltage signal from the zirconia sensor via the nineteenth signal line. U or0 Passed to the second internal resistance calculation block;

[0034] After the second relay and the second internal resistance calculation block receive the start internal resistance test command sent by the zirconia analyzer's out-of-tolerance test module via the fifth signal line, the common terminal of the two contact points of the second relay is connected to its normally open contact. The two ends of the second standard resistor are respectively connected to the positive signal input line and the negative signal input line of the zirconia sensor. The second internal resistance calculation block reads the voltage value signal measured by the background potential test module via the nineteenth signal line. U orb The resistance between the positive and negative signal input lines of the zirconia sensor is calculated using the following formula within the second internal resistance calculation block. R or Perform the calculation:

[0035] ;

[0036] in, R orb This is the resistance value of the second standard resistor; U or0 The voltage value measured by the background potential test module before receiving the start internal resistance test command; U orb The voltage value measured by the background potential test module after receiving the start internal resistance test command;

[0037] The second internal resistance calculation block transmits the calculation results to the zirconia analyzer out-of-tolerance test module via the fifth signal line;

[0038] After the second relay and the second internal resistance calculation block receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the fifth signal line, the common terminal of the two docking points of the second relay is disconnected from its normally open contact, and the two ends of the second standard resistor are disconnected from the positive signal input line and the negative signal input line of the zirconia sensor, respectively.

[0039] The zirconia analyzer out-of-tolerance testing module also receives the oxygen signal from a second zirconia analyzer via the thirteenth signal line. The second zirconia analyzer is installed on the same process pipeline near this zirconia analyzer. The zirconia analyzer out-of-tolerance testing module contains a timing operation block. The first internal resistance testing module measures the resistance of the temperature sensor as follows: R T The second internal resistance testing module measured the internal resistance of the zirconia sensor to be... Ro The background potential test module measured the background potential of the zirconia sensor to be: E 0. The zirconia analyzer out-of-tolerance test module receives the oxygen signal from the second zirconia analyzer via the thirteenth signal line. X 2. The zirconia analyzer's out-of-tolerance test module receives the oxygen signal sent by the oxygen measurement and calculation control module. X 1;

[0040] The out-of-tolerance logic operation of the out-of-tolerance test module of the zirconia analyzer is as follows:

[0041] If any of the following conditions are met, the zirconia analyzer will be considered out of tolerance, and the out-of-tolerance test module will issue an out-of-tolerance alarm:

[0042] ① Internal resistance of the zirconium oxide sensor Ro ≥a, where a is the probe internal resistance limit of the zirconia sensor that does not exceed the tolerance;

[0043] ② Absolute value of the resistance change of the temperature sensor | R T - R T0 |≥η, R T0 η is the initial value of the internal resistance of the temperature sensor, and η is the resistance variation limit of the temperature sensor that does not exceed the tolerance.

[0044] ③ Absolute value of the background potential change of the zirconia sensor | E 0- E 00 |≥θ, E 00 θ is the initial value of the zirconia sensor's base potential, and θ is the allowable drift value of the zirconia sensor's base potential within tolerance.

[0045] ④︱ X 1- X2︱≥m, where m is the limit of the difference between the oxygen value measured by the oxygen measurement and calculation control module and the oxygen value measured by the second zirconia analyzer;

[0046] a, R T0 ,η, E 00 θ and m are stored in the memory inside the out-of-tolerance testing module of the zirconia analyzer.

[0047] This invention has significant substantive features and remarkable progress compared to existing technologies. Specifically, the working principle of this invention is as follows: a temperature sensor measures the temperature of a zirconia sensor; an oxygen measurement and calculation control module controls an electric heater to heat the zirconia sensor, maintaining a stable temperature; the oxygen measurement and calculation control module receives measurement signals from the zirconia sensor and the temperature sensor, calculates the oxygen content based on the Nernst formula, and outputs the oxygen content value; a second internal resistance testing module tests the internal resistance of the zirconia sensor; if the internal resistance value is within the allowable range, it indicates that the zirconia sensor circuit is normal; a first internal resistance testing module tests the internal resistance of the temperature sensor; if the internal resistance value is within the allowable range, it indicates that the temperature sensor circuit is normal; a background potential testing module tests the background potential of the zirconia sensor; if the change in the background potential is within the allowable range, it indicates that the zirconia sensor is functioning normally; only if all three tests are within the allowable range can the oxygen content detection result of the zirconia analyzer be accurate.

[0048] The zirconia analyzer out-of-tolerance test module controls the first internal resistance test module, the second internal resistance test module, and the background potential test module to perform tests. Finally, the zirconia analyzer out-of-tolerance test module calculates and analyzes the test results and outputs a zirconia analyzer detection signal to indicate whether the test results are out of tolerance.

[0049] This invention can determine the accuracy of a zirconia analyzer throughout its entire lifecycle without calibration or maintenance, solving the problem of frequent calibration of zirconia analyzers, reducing maintenance costs, and eliminating the need for maintenance throughout the entire lifecycle of the zirconia analyzer. Attached Figure Description

[0050] Picture 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention.

[0051] Picture 2 This is the first internal resistance testing module of Embodiment 1 of the present invention.

[0052] Picture 3 This is a schematic diagram of the internal circuit structure of Embodiment 1 of the present invention.

[0053] Picture 4 This is a schematic diagram of the structure of Embodiment 2 of the present invention.

[0054] Picture 5 This is a schematic diagram of the internal circuit structure of the first internal resistance testing module in Embodiment 2 of the present invention.

[0055] Picture 6 This is a schematic diagram of the internal circuit structure connection of the background potential test module and the second internal resistance test module in Embodiment 2 of the present invention. Detailed Implementation

[0056] The embodiments of the present invention are further described below with reference to the accompanying drawings. Example 1

[0057] like Picture 1-3 As shown, a calibration-free and maintenance-free zirconia analyzer includes an outer tube 5, a fixed flange 3, a zirconia sensor 1, an electric heater 4, a temperature sensor 2, a first internal resistance testing module 6, a second internal resistance testing module 7, a background potential testing module 8, a zirconia analyzer out-of-tolerance testing module 9, and an oxygen measurement and calculation control module 10. The fixed flange 3 is sealed and fixedly installed at the end of the outer tube 5. The zirconia sensor 1 is coaxially disposed inside the outer tube 5 and sealed and fixedly connected to the middle of the inner end of the fixed flange 3. The electric heater 4 is coaxially disposed between the zirconia sensor 1 and the outer tube 5 and fixed on the inner wall of the end of the outer tube 5. The temperature sensor 2 is disposed inside the zirconia sensor 1.

[0058] The first internal resistance test module 6, the second internal resistance test module 7, the background potential test module 8, the zirconia analyzer out-of-tolerance test module 9, and the oxygen measurement and calculation control module 10 are all composed of electronic circuit boards.

[0059] Temperature sensor 2 transmits its signal to the first internal resistance testing module 6 via the first signal line 101. Zirconia sensor 1 transmits its signal to the second internal resistance testing module 7 via the second signal line 201. Electric heater 4 is connected to oxygen measurement and calculation control module 9 via control line 401. The second internal resistance testing module 7 transmits its signal to the background potential testing module 8 via the third signal line 202. The second internal resistance testing module 7 transmits its signal to the oxygen measurement and calculation control module 10 via the fourth signal line 203. The second internal resistance testing module 7 is connected to the zirconia analyzer tolerance testing module 9 via the fifth signal line 701. The first internal resistance testing module 6 is connected to the zirconia analyzer tolerance testing module 9 via the sixth signal line 601. 9. Signal connection: The first internal resistance test module 6 transmits the signal from the temperature sensor 2 to the oxygen measurement and calculation control module 10 via the seventh signal line 102; the zirconia analyzer out-of-tolerance test module 9 is connected to the oxygen measurement and calculation control module via the eighth signal line 1001; the background potential test module 8 is connected to the zirconia analyzer out-of-tolerance test module 9 via the ninth signal line 801; the zirconia analyzer out-of-tolerance test module 9 is connected to the out-of-tolerance alarm via the tenth signal line 903; the zirconia analyzer out-of-tolerance test module 9 receives the external start internal resistance test command via the eleventh signal line 901; the zirconia analyzer out-of-tolerance test module 9 receives the background potential signal of the zirconia sensor 1 that allows testing via the twelfth signal line 902; and the zirconia analyzer out-of-tolerance test module 9 has an internal timing calculation block.

[0060] After receiving the start internal resistance test command from the zirconia analyzer over-tolerance test module 9 via the fifth signal line 701, the second internal resistance test module 7 begins to test the internal resistance of the zirconia sensor 1 and sends the test result to the zirconia analyzer over-tolerance test module 9 via the fifth signal line 701. After receiving the start status test command from the zirconia analyzer over-tolerance test module 9 via the ninth signal line 801, the background potential test module 8 begins to test the potential of the third signal line 202 of the zirconia sensor 1, uses the test result as the background potential of the zirconia sensor 1, and sends the test result to the zirconia analyzer over-tolerance test module 9 via the ninth signal line 801. After receiving the start internal resistance test command from the zirconia analyzer over-tolerance test module 9 via the sixth signal line 601, the first internal resistance test module 6 begins to test the internal resistance of the temperature sensor 2 and sends the test result to the zirconia analyzer over-tolerance test module 9 via the sixth signal line 601.

[0061] The zirconia analyzer out-of-tolerance test module 9 can receive external commands via the eleventh signal line 901 to start and stop the internal resistance test logic operation. The timing calculation block inside the zirconia analyzer out-of-tolerance test module 9 can preset the test cycle in advance. After the preset time is reached, or after receiving an external start internal resistance test command through the eleventh signal line 901, the zirconia analyzer out-of-tolerance test module 9 issues a start internal resistance test command. First, it sends a "resistance test started" signal to the oxygen measurement and calculation control module 10 through the eighth signal line 1001. Then, after performing a delay calculation on the command, it sends a start internal resistance test command to the first internal resistance test module 6 and the second internal resistance test module 7. After receiving the "resistance test started" signal, the oxygen measurement and calculation control module 10 keeps the internal resistance value of the zirconia sensor 1 or the internal resistance value of the temperature sensor 2 unchanged.

[0062] After receiving the signal allowing the testing of the background potential of the zirconia analyzer 9 through the twelfth signal line 902, the zirconia analyzer out-of-tolerance test module 9 performs logical operations and sends a "start state test command" to the background potential test module 8. After receiving the command, the background potential test module 8 begins to test the background potential of the zirconia analyzer 1.

[0063] After the zirconia analyzer out-of-tolerance testing module 9 sends test commands to the background potential testing module 8, the second internal resistance testing module 7, and the first internal resistance testing module 6, the background potential testing module 8, the second internal resistance testing module 7, and the first internal resistance testing module 6 respectively measure the background potential of the zirconia sensor 1. E 0. Internal resistance value of zirconium oxide sensor 1 Ro The internal resistance value of temperature sensor 2 R T The signal is sent to the zirconia analyzer out-of-tolerance test module 9; the zirconia analyzer out-of-tolerance test module 9 performs the following out-of-tolerance analysis logic operation:

[0064] The following conditions must be met for a zirconia analyzer to be out of tolerance:

[0065] ① Internal resistance of zirconium oxide sensor 1 Ro ≥a, where a is the probe internal resistance limit of the zirconia sensor 1 that does not exceed the tolerance;

[0066] ② Absolute value of resistance change of temperature sensor 2 | R T - R T0 |≥η, RT0 η is the initial value of the internal resistance of temperature sensor 2, and η is the resistance change limit of temperature sensor 2 that does not exceed the tolerance.

[0067] ③ Absolute value of the background potential change of zirconium oxide sensor 1 | E 0- E 00 |≥θ, E 00 θ is the initial value of the background potential of zirconia sensor 1, and θ is the allowable drift value of the background potential of zirconia sensor 1 without exceeding the tolerance.

[0068] a, R T0 ,η, E 00 θ is stored in the memory inside the out-of-tolerance test module 9 of the zirconia analyzer.

[0069] After the out-of-tolerance analysis logic operation is completed, the out-of-tolerance test module 9 of the zirconia analyzer sends the logic operation result to the out-of-tolerance alarm through the tenth signal line 903; if the out-of-tolerance analysis logic operation result indicates that the zirconia analyzer is out of tolerance, the out-of-tolerance alarm will sound an alarm to remind the monitoring personnel to take timely action.

[0070] The zirconia analyzer out-of-tolerance test module 9 measures the background potential of the zirconia sensor 1, which is measured by the background potential test module 8. E The system sends a signal to the oxygen measurement and calculation control module 10, which in turn receives the background potential from the zirconium oxide sensor 1. E 0 performs oxygen content calculation to determine the oxygen content P of the measured gas. The oxygen content calculation formula is:

[0071] ;

[0072] in, E The concentration cell potential is given in mV. k For coefficients; P 0 represents the oxygen content in the air (%), and P represents the oxygen content in the gas being measured (%). E 0 represents the background potential of the zirconium oxide sensor 1 measured by the background potential test module 8, in mV.

[0073] After the out-of-tolerance analysis logic operation is completed, the out-of-tolerance test module 9 of the zirconia analyzer sends a stop test normal operation command to the oxygen measurement and calculation control module 10, the second internal resistance test module 7, the first internal resistance test module 6, and the background potential test module 8 through their respective signal lines. Upon receiving the stop test command, the oxygen measurement and calculation control module 10 begins normal oxygen measurement.

[0074] The internal circuit structure of the first internal resistance testing module 6 includes a first relay 61 and a first resistance testing block 62. Both the first relay 61 and the first resistance testing block 62 are connected to the zirconia analyzer out-of-tolerance testing module 9 via the sixth signal line 601. The common terminal of the first contact point of the first relay 61 is connected to the positive signal input line 1011 of the temperature sensor 2. The normally closed terminal of the first contact point of the first relay 61 is connected to the positive signal output line 1021 of the temperature sensor 2. The normally open contact of the first contact point of the first relay 61 is connected to the first resistance testing module 9 via the twenty-first signal line 6201. In test block 62, the common terminal of the first contact point of the first relay 61 is connected to its normally closed terminal and normally open contact via a first single-pole double-throw switch. The common terminal of the second contact point of the first relay 61 is connected to a negative signal input line 1012. The normally closed terminal of the second contact point of the first relay 61 is connected to a negative signal output line 1022. The normally open contact of the second contact point of the first relay 61 is connected to the first resistance test block 62 via a twenty-second signal line 6202. The common terminal of the second contact point of the first relay 61 is connected to its normally closed terminal and normally open contact via a second single-pole double-throw switch.

[0075] After receiving the start internal resistance test command sent by the zirconia analyzer out-of-tolerance test module 9 through the sixth signal line 601, the first relay 61 is activated. The common terminal of the first and second contact points of the first relay 61 is connected to its normally open contact. The positive signal input line 1011 and the negative signal input line 1012 of the temperature sensor 2 are respectively connected to the twenty-first signal line 6201 and the twenty-second signal line 6202 and connected to the first resistance test block 62. The first resistance test block 62 tests the resistance between the positive signal input line 1011 and the negative signal input line 1012 of the temperature sensor 2. The first resistance test block 62 sends the test result to the zirconia analyzer out-of-tolerance test module 9 through the sixth signal line 601.

[0076] After receiving the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module 9 through the sixth signal line 601, the first relay 61 returns to its original state, and the common terminal of the first and second contact points of the first relay 61 is connected to its normally closed terminal. The positive signal input line 1011 and the negative signal input line 1012 of the temperature sensor 2 are connected to the positive signal output line 1021 and the negative signal output line 1022 respectively, and the common terminal of the first and second contact points of the first relay 61 is disconnected from its normally open contact.

[0077] The internal circuit structure of the second internal resistance test module 7 includes a second relay 71 and a second resistance test block 72. Both the second relay 71 and the second resistance test block 72 are connected to the zirconia analyzer out-of-tolerance test module 9 via the fifth signal line 701. The common terminal of the first contact point of the second relay 71 is connected to the positive signal input line 2011 of the zirconia sensor 1, and the normally closed terminal of the first contact point of the second relay 71 is connected to the positive signal output line 2021 of the zirconia sensor 1. The normally open contact of the first contact point of the second relay 71 is connected to the second resistance test block 7201 via the twenty-fifth signal line 7201. In test block 72, the common terminal of the first contact point of the second relay 71 is connected to its normally closed terminal and normally open contact via a first single-pole double-throw switch. The common terminal of the second contact point of the second relay 71 is connected to a negative signal input line 2012. The normally closed terminal of the second contact point of the second relay 71 is connected to a negative signal output line 2022. The normally open contact of the second contact point of the second relay 71 is connected to the second resistance test block 72 via a twenty-sixth signal line 7202. The common terminal of the second contact point of the second relay 71 is connected to its normally closed terminal and normally open contact via a second single-pole double-throw switch.

[0078] After receiving the start internal resistance test command sent by the zirconia analyzer out-of-tolerance test module 9 through the fifth signal line 701, the second relay 71 is activated. The common terminal of the first and second contact points of the second relay 71 is connected to its normally open contact. The positive signal input line 2011 and the negative signal input line 2012 of the zirconia sensor 1 are connected to the twenty-fifth signal line 7201 and the twenty-sixth signal line 7202 respectively and connected to the second resistance test block 72. The second resistance test block 72 tests the resistance between the positive signal input line 2011 and the negative signal input line 2012 of the zirconia sensor 1. The second resistance test block 72 sends the test result to the zirconia analyzer out-of-tolerance test module 9 through the fifth signal line 701.

[0079] After the second relay 71 and the second resistance test block 72 receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module 9 through the fifth signal line 701, the second relay 71 returns to its original state, and the common terminal of the first and second contact points of the second relay 71 is connected to its normally closed terminal. The positive signal input line 2011 and the negative signal input line 2012 of the zirconia sensor 1 are connected to the positive signal output line 2021 and the negative signal output line 2022 respectively, and the common terminal of the first and second contact points of the second relay 71 is disconnected from its normally open contact. Example 2

[0080] like Picture 4-6A calibration-free and maintenance-free zirconia analyzer includes an outer tube 5, a fixed flange 3, a zirconia sensor 1, an electric heater 4, a temperature sensor 2, a first internal resistance testing module 6, a second internal resistance testing module 7, a background potential testing module 8, a zirconia analyzer out-of-tolerance testing module 9, and an oxygen measurement and calculation control module 10. The fixed flange 3 is sealed and fixedly installed at the end of the outer tube 5. The zirconia sensor 1 is coaxially disposed inside the outer tube 5 and sealed and fixedly connected to the middle of the inner end of the fixed flange 3. The electric heater 4 is coaxially disposed between the zirconia sensor 1 and the outer tube 5 and fixedly connected to the inner side of the fixed flange 3. The temperature sensor 2 is disposed on the inner end face of the zirconia sensor 1.

[0081] The first internal resistance test module 6, the second internal resistance test module 7, the background potential test module 8, the zirconia analyzer out-of-tolerance test module 9, and the oxygen measurement and calculation control module 10 are all composed of electronic circuit boards.

[0082] Temperature sensor 2 transmits its signal to the first internal resistance testing module 6 via the first signal line 101. Zirconia sensor 1 transmits its signal to the second internal resistance testing module 7 via the second signal line 201. Electric heater 4 is connected to the oxygen measurement and calculation control module 10 via control line 401. The second internal resistance testing module 7 transmits its signal to the background potential testing module 8 via the third signal line 202. The second internal resistance testing module 7 receives the voltage signal measured by the background potential testing module 8 via the nineteenth signal line 205. The second internal resistance testing module 7 is connected to the zirconia analyzer tolerance testing module 9 via the fifth signal line 701. The background potential testing module 8 transmits its voltage signal to the oxygen measurement and calculation control module 10 via the twenty-third signal line 206. The background potential testing module 8 and the zirconia analyzer tolerance testing module 9 are connected via the ninth signal line 801. The first internal resistance testing module... The first internal resistance test module 6 is connected to the zirconia analyzer out-of-tolerance test module 9 via the sixth signal line 601. The first internal resistance test module 6 transmits the signal from the temperature sensor 2 to the oxygen measurement and calculation control module 10 via the twenty-fourth signal line 105. The zirconia analyzer out-of-tolerance test module 9 is connected to the oxygen measurement and calculation control module 10 via the eighth signal line 1001. The zirconia analyzer out-of-tolerance test module 9 is connected to the remote monitoring device via the tenth signal line 903. The zirconia analyzer out-of-tolerance test module 9 receives the external start internal resistance test command via the eleventh signal line 901. The zirconia analyzer out-of-tolerance test module 9 receives the background potential signal of the zirconia sensor 1 that allows testing via the twelfth signal line 902. The zirconia analyzer out-of-tolerance test module 9 receives the oxygen signal sent by the second zirconia analyzer via the thirteenth signal line 5001. The second zirconia analyzer is installed on the same process pipeline near this zirconia analyzer. The zirconia analyzer out-of-tolerance test module 9 is equipped with a timing calculation block.

[0083] After receiving the start internal resistance test command from the zirconia analyzer out-of-tolerance test module 9 via the fifth signal line 701, the second internal resistance test module 7 begins to test the internal resistance of the zirconia sensor 1 and sends the test result to the zirconia analyzer out-of-tolerance test module 9 via the fifth signal line 701. After receiving the start internal resistance test command from the zirconia analyzer out-of-tolerance test module 9 via the sixth signal line 601, the first internal resistance test module 6 begins to test the internal resistance of the temperature sensor 2 and sends the test result to the zirconia analyzer out-of-tolerance test module 9 via the sixth signal line 601.

[0084] The zirconia analyzer out-of-tolerance test module 9 can receive external commands via the eleventh signal line 901 to start and stop the internal resistance test logic operation. The timing calculation block inside the zirconia analyzer out-of-tolerance test module 9 can preset the test cycle in advance. After the preset time is reached, or after receiving an external start internal resistance test command through the eleventh signal line 901, the zirconia analyzer out-of-tolerance test module 9 issues a start internal resistance test command. First, it sends a "resistance test started" signal to the oxygen measurement and calculation control module 10 through the eighth signal line 1001. Then, after performing a delay calculation on the command, it sends a start internal resistance test command to the first internal resistance test module 6 and the second internal resistance test module 7. After receiving the "resistance test started" signal, the oxygen measurement and calculation control module 10 keeps the internal resistance value of the zirconia sensor 1 or the internal resistance value of the temperature sensor 2 unchanged.

[0085] After receiving a signal allowing the testing of the zirconia analyzer's background potential 1 via the twelfth signal line 902, the zirconia analyzer's out-of-tolerance test module 9 performs logical operations and then sends a "start-up test command" to the background potential test module 8. Upon receiving the command, the background potential test module 8 begins testing the background potential of the zirconia analyzer 1. The signal allowing the testing of the zirconia analyzer 1's background potential can be the oxygen quantity signal sent by the second zirconia analyzer to the zirconia analyzer's out-of-tolerance test module 9 via the thirteenth signal line 5001 when the second zirconia analyzer detects that the process pipeline is full of air. X 2. It could also be a signal sent by a staff member manually pressing a button when they determine that the process pipeline is full of air.

[0086] After the zirconia analyzer out-of-tolerance testing module 9 sends test commands to the background potential testing module 8, the second internal resistance testing module 7, and the first internal resistance testing module 6, the background potential testing module 8, the second internal resistance testing module 7, and the first internal resistance testing module 6 respectively measure the background potential of the zirconia sensor 1. E 0. Internal resistance value of zirconium oxide sensor 1 Ro The internal resistance value of temperature sensor 2 R T The signal is sent to the zirconia analyzer out-of-tolerance test module 9, and at the same time, the zirconia analyzer out-of-tolerance test module 9 receives the oxygen signal sent by the second zirconia analyzer through the thirteenth signal line 5001. X 2. The zirconia analyzer out-of-tolerance test module 9 receives the oxygen signal sent by the oxygen measurement and calculation control module 10. X 1. The out-of-tolerance test module 9 of the zirconia analyzer performs the following out-of-tolerance analysis logic operations:

[0087] The following conditions must be met for a zirconia analyzer to be out of tolerance:

[0088] ① Internal resistance of zirconium oxide sensor 1 Ro ≥a, where a is the probe internal resistance limit of the zirconia sensor 1 that does not exceed the tolerance;

[0089] ② Absolute value of resistance change of temperature sensor 2 | R T - R T0 |≥η, R T0 η is the initial value of the internal resistance of temperature sensor 2, and η is the resistance change limit of temperature sensor 2 that does not exceed the tolerance.

[0090] ③ Absolute value of the background potential change of zirconium oxide sensor 1 | E 0- E 00 |≥θ, E 00 θ is the initial value of the background potential of zirconia sensor 1, and θ is the allowable drift value of the background potential of zirconia sensor 1 without exceeding the tolerance.

[0091] ④︱ X 1- X 2︱≥m, where m is the limit of the difference between the oxygen value measured by the oxygen measurement and calculation control module 10 and the oxygen value measured by the second zirconia analyzer.

[0092] a, R T0 ,η, E 00 θ and m are stored in the memory inside the out-of-tolerance test module 9 of the zirconia analyzer.

[0093] After the out-of-tolerance analysis logic operation is completed, the out-of-tolerance test module 9 of the zirconia analyzer sends the logic operation result to the remote monitoring equipment through the tenth signal line 903; if the out-of-tolerance analysis logic operation result is that the zirconia analyzer is out of tolerance, the remote monitoring equipment will issue an alarm to remind the monitoring personnel to take timely action.

[0094] The zirconia analyzer out-of-tolerance test module 9 measures the background potential of the zirconia sensor 1, which is measured by the background potential test module 8. E The system sends a signal to the oxygen measurement and calculation control module 10, which in turn receives the background potential from the zirconium oxide sensor 1. E 0 performs oxygen content calculation to determine the oxygen content P of the measured gas. The oxygen content calculation formula is:

[0095] ;

[0096] in, E The concentration cell potential is given in mV. k For coefficients; P 0 represents the oxygen content in the air (%), and P represents the oxygen content in the gas being measured (%). E 0 represents the background potential of the zirconium oxide sensor 1 measured by the background potential test module 8, in mV.

[0097] After the out-of-tolerance analysis logic operation is completed, the out-of-tolerance test module 9 of the zirconia analyzer sends a stop test normal operation command to the oxygen measurement and calculation control module 10, the second internal resistance test module 7, the first internal resistance test module 6, and the background potential test module 8 through their respective signal lines. Upon receiving the stop test command, the oxygen measurement and calculation control module 10 begins normal oxygen measurement.

[0098] The internal circuit structure of the first internal resistance testing module 6 includes a first standard resistor 34, a first relay 31, a voltage testing block 32, and a first internal resistance calculation block 33. The first relay 31, voltage testing block 32, and first internal resistance calculation block 33 are all connected to the zirconia analyzer out-of-tolerance testing module 9 via the sixth signal line 601. The positive signal input line 1011 and negative signal input line 1012 of the temperature sensor 2 are respectively connected to the normally open contacts of the two terminals of the first relay 31. The common terminal of the two terminals of the first relay 31 is connected to both ends of the first standard resistor 34. The positive signal input line 1011 and negative signal input line 1012 of the temperature sensor 2 are also connected to the voltage testing block 32 via the eighteenth signal line. The voltage testing block 32 transmits the measured voltage value signal from the temperature sensor 2 via the fifteenth signal line 321. U Tb The voltage is transmitted to the first internal resistance calculation block 33, and the voltage test block 32 transmits the measured voltage signal from the temperature sensor 2 via the twenty-fourth signal line 105. U Tb The resistance value of the measured temperature sensor 2 is transmitted to the oxygen measurement and calculation control module 10 via the 27th signal line 107. The first internal resistance calculation block 33 then transmits the resistance value of the measured temperature sensor 2 to the oxygen measurement and calculation control module 10. R T Oxygen measurement, calculation, and control module 10;

[0099] After the first relay 31, voltage test block 32, and first internal resistance calculation block 33 receive the start internal resistance test command sent by the zirconia analyzer out-of-tolerance test module 9 through the sixth signal line 601, the common terminal of the two contact points of the first relay 31 is connected to its normally open contact. The two ends of the first standard resistor 34 are respectively connected to the positive signal input line 1011 and the negative signal input line 1012 of the temperature sensor 2. The voltage test block 32 transmits the measured voltage value signal. U TbThe signal is transmitted to the first internal resistance calculation block 33 via the fifteenth signal line 321. The first internal resistance calculation block 33 calculates the resistance between the positive signal input line 1011 and the negative signal input line 1012 of signal 2 using the following formula. R T Perform the calculation:

[0100] ;

[0101] Among them, R Tb This is the resistance value of the first standard resistor, 34. U T0 The voltage value measured in voltage test block 32 before receiving the start internal resistance test command; U Tb The voltage value measured by voltage test block 32 after receiving the start internal resistance test command;

[0102] The first internal resistance calculation block 33 transmits the calculation result to the zirconia analyzer out-of-tolerance test module 9 via the sixth signal line 601;

[0103] After the first relay 31, voltage test block 32, and first internal resistance calculation block 33 receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module 9 through the sixth signal line 601, the common terminal of the two docking points of the first relay 31 is disconnected from its normally open contact, and the two ends of the first standard resistor 34 are disconnected from the positive signal input line 1011 and the negative signal input line 1012 of the temperature sensor 2, respectively.

[0104] The internal circuit structure of the second internal resistance testing module 7 includes a second relay 71, a second internal resistance calculation block 72, and a second standard resistor 73. Both the second relay 71 and the second internal resistance calculation block 72 are connected to the zirconia analyzer out-of-tolerance testing module 9 via the fifth signal line 701. The positive signal input line 2011 and the negative signal input line 2012 of the zirconia sensor 1 are respectively connected to the normally open contacts of the two terminals of the second relay 71. The common terminal of the two terminals of the second relay 71 is connected to both ends of the second standard resistor 73. The positive signal input line 2011 and the negative signal input line 2012 of the zirconia sensor 1 are also connected to the background potential testing module 8 via the third signal line 202 (signal lines 2021 and 2022). The background potential testing module 8 transmits the voltage value signal measured by the zirconia sensor 1 via the nineteenth signal line 205. U or0 The voltage signal from the zirconia sensor 1 is transmitted to the second internal resistance calculation block 72, and the background potential test module 8 also transmits the measured voltage signal to the 23rd signal line 206. U or0 The signal is transmitted to the oxygen measurement and calculation control module 10, which receives the voltage signal from the tested zirconium oxide sensor 1.U or0 Perform oxygen content calculation;

[0105] After the second relay 71 and the second internal resistance calculation block 72 receive the start internal resistance test command sent by the zirconia analyzer out-of-tolerance test module 9 through the fifth signal line 701, the common terminal of the two contact points of the second relay 71 is connected to its normally open contact. The two ends of the second standard resistor 73 are respectively connected to the positive signal input line 2011 and the negative signal input line 2012 of the zirconia sensor 1. The second internal resistance calculation block 72 reads the voltage value signal measured by the background potential test module 8 through the nineteenth signal line 205. U orb The resistance between the positive signal input line 2011 and the negative signal input line 2012 of the zirconia sensor 1 is calculated using the following formula within the second internal resistance calculation block 72. R or Perform the calculation:

[0106] ;

[0107] in, R orb This is the resistance value of the second standard resistor, 73. U or0 The voltage value measured by the background potential test module 8 before receiving the start internal resistance test command; U orb The voltage value measured by the background potential test module 8 after receiving the start internal resistance test command;

[0108] The second internal resistance calculation block 72 transmits the calculation result to the zirconia analyzer out-of-tolerance test module 9 via the fifth signal line 701;

[0109] After the second relay 71 and the second internal resistance calculation block 72 receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module 9 through the fifth signal line 701, the common terminal of the two docking points of the second relay 71 is disconnected from its normally open contact, and the two ends of the second standard resistor 73 are disconnected from the positive signal input line 2011 and the negative signal input line 2012 of the zirconia sensor 1, respectively.

[0110] The above embodiments are only used to illustrate and not limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention without departing from the spirit and scope of the present invention. Any modifications or partial substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A calibration-free and maintenance-free zirconia analyzer, characterized in that: It includes an outer tube, a fixed flange, a zirconia sensor, an electric heater, a temperature sensor, an internal resistance testing module, a background potential testing module, a zirconia analyzer out-of-tolerance testing module, and an oxygen measurement and calculation control module. The fixed flange is sealed and fixedly installed at the end of the outer tube. The zirconia sensor is coaxially installed inside the outer tube and sealed and fixedly connected to the middle of the inner end of the fixed flange. The electric heater is coaxially installed between the zirconia sensor and the outer tube and fixedly connected to the inner wall of the end of the outer tube. The temperature sensor is installed at the inner end of the zirconia sensor. The internal resistance testing module is divided into a first internal resistance testing module and a second internal resistance testing module. The first internal resistance test module, the second internal resistance test module, the background potential test module, the zirconia analyzer out-of-tolerance test module, and the oxygen measurement and calculation control module are all composed of electronic circuit boards; The temperature sensor transmits its signal to the first internal resistance test module via the first signal line. The zirconia sensor transmits its signal to the second internal resistance test module via the second signal line. The electric heater is connected to the oxygen measurement and calculation control module via a control line. The second internal resistance test module transmits its signal to the background potential test module via the third signal line. The second internal resistance test module is connected to the zirconia analyzer out-of-tolerance test module via the fifth signal line. The first internal resistance test module is connected to the zirconia analyzer out-of-tolerance test module via the sixth signal line. The zirconia analyzer out-of-tolerance test module is connected to the oxygen measurement and calculation control module via the eighth signal line. The background potential test module is connected to the zirconia analyzer out-of-tolerance test module via the ninth signal line. The zirconia analyzer out-of-tolerance test module is connected to the out-of-tolerance alarm via the tenth signal line. The zirconia analyzer out-of-tolerance test module receives an external command to start the internal resistance test via the eleventh signal line. The zirconia analyzer out-of-tolerance test module receives a signal indicating permission to test the zirconia sensor background potential via the twelfth signal line. The zirconia analyzer out-of-tolerance test module has a timing calculation block inside. The first internal resistance testing module measured the resistance of the temperature sensor as follows: R T The second internal resistance testing module measured the internal resistance of the zirconia sensor to be... Ro The background potential test module measured the background potential of the zirconia sensor to be: E 0; The out-of-tolerance logic operation of the out-of-tolerance test module of the zirconia analyzer is as follows: If any of the following conditions are met, the zirconia analyzer will be considered out of tolerance, and the out-of-tolerance test module will issue an out-of-tolerance alarm: ① Internal resistance of the zirconium oxide sensor Ro ≥a, where a is the probe internal resistance limit of the zirconia sensor that does not exceed the tolerance; ② Absolute value of the resistance change of the temperature sensor | R T - R T0 |≥η, R T0 η is the initial value of the internal resistance of the temperature sensor, and η is the resistance variation limit of the temperature sensor that does not exceed the tolerance. ③ Absolute value of the background potential change of the zirconia sensor | E 0- E 00 |≥θ, E 00 θ is the initial value of the zirconia sensor's base potential, and θ is the allowable drift value of the zirconia sensor's base potential within tolerance. a, R T0 ,η, E 00 θ is stored in the memory inside the out-of-tolerance test module of the zirconia analyzer; The internal circuit structure of the first internal resistance test module includes a first relay and a first resistance test block. Both the first relay and the first resistance test block are connected to the zirconia analyzer out-of-tolerance test module via the sixth signal line. The common terminal of the first contact of the first relay is connected to the positive signal input line of the temperature sensor. The normally closed terminal of the first contact of the first relay is connected to the positive signal output line of the temperature sensor of the first internal resistance test module. The normally open contact of the first contact of the first relay is connected to the first resistance test block via the twenty-first signal line. The common terminal of the second contact of the first relay is connected to the negative signal input line of the temperature sensor. The normally closed terminal of the second contact of the first relay is connected to the negative signal output line of the temperature sensor of the first internal resistance test module. The normally open contact of the second contact of the first relay is connected to the first resistance test block via the twenty-second signal line. After receiving the start internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the sixth signal line, the first relay activates, and the common terminal of the first and second contact points of the first relay is connected to its normally open contact. The positive and negative signal input lines of the temperature sensor are respectively connected to the twenty-first and twenty-second signal lines and connected to the first resistance test block. The first resistance test block tests the resistance between the positive and negative signal input lines of the temperature sensor and sends the test results to the zirconia analyzer out-of-tolerance test module through the sixth signal line. After the first relay and the first resistance test block receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the sixth signal line, the first relay returns to its original state, the common terminal of the first and second contact points of the first relay is connected to its normally closed terminal, the positive signal input line and negative signal input line of the temperature sensor are connected to the positive signal output line and negative signal output line of the temperature sensor respectively, and the common terminal of the first and second contact points of the first relay is disconnected from its normally open contact. The internal circuit structure of the second internal resistance test module includes a second relay and a second resistance test block. Both the second relay and the second resistance test block are connected to the zirconia analyzer out-of-tolerance test module via the fifth signal line. The common terminal of the first contact of the second relay is connected to the positive signal input line of the zirconia sensor, and the normally closed terminal of the first contact of the second relay is connected to the positive signal output line of the zirconia sensor in the second internal resistance test module. The normally open contact of the second contact of the second relay is connected to the second resistance test block via the twenty-fifth signal line. The common terminal of the second contact of the second relay is connected to the negative signal input line of the zirconia sensor, and the normally closed terminal of the second contact of the second relay is connected to the negative signal output line of the zirconia sensor in the second internal resistance test module. The normally open contact of the second contact of the second relay is connected to the second resistance test block via the twenty-sixth signal line. After receiving the start internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the fifth signal line, the second relay activates, and the common terminal of the first and second contact points of the second relay is connected to its normally open contact. The positive signal input line and negative signal input line of the zirconia sensor are respectively connected to the twenty-fifth and twenty-sixth signal lines and connected to the second resistance test block. The second resistance test block tests the resistance between the positive signal input line and the negative signal input line of the zirconia sensor and sends the test result to the zirconia analyzer out-of-tolerance test module through the fifth signal line. After the second relay and the second resistance test block receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the fifth signal line, the second relay returns to its original state, and the common terminal of the first and second contact points of the second relay is connected to its normally closed terminal. The positive signal input line and negative signal input line of the zirconia sensor are connected to the positive signal output line and negative signal output line of the zirconia sensor, respectively. The common terminal of the first and second contact points of the second relay is disconnected from its normally open contact. The signal output line of the first internal resistance test module is connected to the seventh signal line, which transmits the signal from the temperature sensor to the oxygen measurement and calculation control module. The signal output line of the second internal resistance test module is connected to the fourth signal line, which transmits the signal from the zirconium oxide sensor to the oxygen measurement and calculation control module.

2. A calibration-free and maintenance-free zirconia analyzer, characterized in that: It includes an outer tube, a fixed flange, a zirconia sensor, an electric heater, a temperature sensor, an internal resistance testing module, a background potential testing module, a zirconia analyzer out-of-tolerance testing module, and an oxygen measurement and calculation control module. The fixed flange is sealed and fixedly installed at the end of the outer tube. The zirconia sensor is coaxially installed inside the outer tube and sealed and fixedly connected to the middle of the inner end of the fixed flange. The electric heater is coaxially installed between the zirconia sensor and the outer tube and fixedly connected to the inner wall of the end of the outer tube. The temperature sensor is installed at the inner end of the zirconia sensor. The internal resistance testing module is divided into a first internal resistance testing module and a second internal resistance testing module. The first internal resistance test module, the second internal resistance test module, the background potential test module, the zirconia analyzer out-of-tolerance test module, and the oxygen measurement and calculation control module are all composed of electronic circuit boards; The temperature sensor transmits its signal to the first internal resistance test module via the first signal line. The zirconia sensor transmits its signal to the second internal resistance test module via the second signal line. The electric heater is connected to the oxygen measurement and calculation control module via a control line. The second internal resistance test module transmits its signal to the background potential test module via the third signal line. The second internal resistance test module is connected to the zirconia analyzer out-of-tolerance test module via the fifth signal line. The first internal resistance test module is connected to the zirconia analyzer out-of-tolerance test module via the sixth signal line. The zirconia analyzer out-of-tolerance test module is connected to the oxygen measurement and calculation control module via the eighth signal line. The background potential test module is connected to the zirconia analyzer out-of-tolerance test module via the ninth signal line. The zirconia analyzer out-of-tolerance test module is connected to the out-of-tolerance alarm via the tenth signal line. The zirconia analyzer out-of-tolerance test module receives an external command to start the internal resistance test via the eleventh signal line. The zirconia analyzer out-of-tolerance test module receives a signal indicating permission to test the zirconia sensor background potential via the twelfth signal line. The zirconia analyzer out-of-tolerance test module has a timing calculation block inside. The first internal resistance testing module measured the resistance of the temperature sensor as follows: R T The second internal resistance testing module measured the internal resistance of the zirconia sensor to be... Ro The background potential test module measured the background potential of the zirconia sensor to be: E 0; The out-of-tolerance logic operation of the out-of-tolerance test module of the zirconia analyzer is as follows: If any of the following conditions are met, the zirconia analyzer will be considered out of tolerance, and the out-of-tolerance test module will issue an out-of-tolerance alarm: ① Internal resistance of the zirconium oxide sensor Ro ≥a, where a is the probe internal resistance limit of the zirconia sensor that does not exceed the tolerance; ② Absolute value of the resistance change of the temperature sensor | R T - R T0 |≥η, R T0 η is the initial value of the internal resistance of the temperature sensor, and η is the resistance variation limit of the temperature sensor that does not exceed the tolerance. ③ Absolute value of the background potential change of the zirconia sensor | E 0- E 00 |≥θ, E 00 θ is the initial value of the zirconia sensor's base potential, and θ is the allowable drift value of the zirconia sensor's base potential within tolerance. a, R T0 ,η, E 00 θ is stored in the memory inside the out-of-tolerance test module of the zirconia analyzer; The internal circuit structure of the first internal resistance testing module includes a first standard resistor, a first relay, a voltage testing block, and a first internal resistance calculation block. The first relay, voltage testing block, and first internal resistance calculation block are all connected to the zirconia analyzer's out-of-tolerance testing module via the sixth signal line. The positive and negative signal input lines of the temperature sensor are respectively connected to the normally open contacts of the two terminals of the first relay. The common terminal of the two terminals of the first relay is connected to both ends of the first standard resistor. The positive and negative signal input lines of the normally open contact temperature sensor are also connected to the voltage testing block via the eighteenth signal line. The voltage testing block transmits the measured voltage value signal from the temperature sensor via the fifteenth signal line. U T0 The signal is transmitted to the first internal resistance calculation block, and the voltage test block transmits the measured voltage value signal from the temperature sensor via the twenty-fourth signal line. U Tb The data is transmitted to the oxygen measurement and calculation control module. The first internal resistance calculation block transmits the measured resistance value of the temperature sensor to the 27th signal line. R T Oxygen measurement, calculation, and control module; After receiving the start internal resistance test command from the zirconia analyzer's out-of-tolerance test module via the sixth signal line, the first relay, voltage test block, and first internal resistance calculation block connect the common terminal of the two contact points of the first relay to its normally open contact. The two ends of the first standard resistor are connected to the positive and negative signal input lines of the temperature sensor, respectively. The voltage test block then transmits the measured voltage signal. U Tb The signal is transmitted to the first internal resistance calculation block via the fifteenth signal line. The first internal resistance calculation block calculates the resistance between the positive and negative signal input lines of the temperature sensor using the following formula. R T Perform the calculation: Among them, R Tb This is the resistance value of the first standard resistor; U T0 The voltage value measured in the voltage test block before receiving the start internal resistance test command; U Tb The voltage value measured by the voltage test block after receiving the start internal resistance test command; The first internal resistance calculation block transmits the calculation results to the zirconia analyzer out-of-tolerance test module via the sixth signal line; After the first relay, voltage test block, and first internal resistance calculation block receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the seventh signal line, the common terminal of the two connection points of the first relay is disconnected from its normally open contact, and the two ends of the first standard resistor are disconnected from the positive signal input line and negative signal input line of the temperature sensor, respectively.

3. The calibrated-free and maintenance-free zirconia analyzer according to claim 1, characterized in that: The background potential testing module transmits the voltage value of the zirconia sensor measured via the ninth signal line to the zirconia analyzer's out-of-tolerance testing module. After receiving the signal allowing testing of the zirconia sensor's background potential via the twelfth signal line, the zirconia analyzer's out-of-tolerance testing module performs calculations and then uses the voltage value of the zirconia sensor received via the ninth signal line as the background electromotive force of the zirconia. E 0. The background potential test module also transmits the voltage value of the tested zirconium oxide sensor to the oxygen measurement and calculation control module through the twenty-third signal line.

4. The calibration-free and maintenance-free zirconia analyzer according to claim 1, characterized in that: The out-of-tolerance test module of the zirconia analyzer measures the background potential of the zirconia sensor. E 0 is sent to the oxygen measurement and calculation control module for oxygen calculation, which calculates the oxygen content P of the measured gas. The oxygen calculation formula is: in, E The concentration cell potential is given in mV. k For coefficients; P 0 represents the oxygen content in the air (%), and P represents the oxygen content in the gas being measured (%). E 0 represents the background potential of the zirconia sensor measured by the background potential testing module, in mV.

5. The calibration-free and maintenance-free zirconia analyzer according to claim 1, characterized in that: The internal circuit structure of the second internal resistance testing module includes a second relay, a second internal resistance calculation block, and a second standard resistor. Both the second relay and the second internal resistance calculation block are connected to the zirconia analyzer's out-of-tolerance testing module via the fifth signal line. The positive and negative signal input lines of the zirconia sensor are connected to the normally open contacts of the two terminals of the second relay, respectively. The common terminal of the two terminals of the second relay is connected to both ends of the second standard resistor. The positive and negative signal input lines of the zirconia sensor are also connected to the background potential testing module via the third signal line. The background potential testing module transmits the measured voltage signal from the zirconia sensor via the nineteenth signal line. U or0 Passed to the second internal resistance calculation block; After the second relay and the second internal resistance calculation block receive the start internal resistance test command sent by the zirconia analyzer's out-of-tolerance test module via the fifth signal line, the common terminal of the two contact points of the second relay is connected to its normally open contact. The two ends of the second standard resistor are respectively connected to the positive signal input line and the negative signal input line of the zirconia sensor. The second internal resistance calculation block reads the voltage value signal measured by the background potential test module via the nineteenth signal line. U orb The resistance between the positive and negative signal input lines of the zirconia sensor is calculated using the following formula within the second internal resistance calculation block. R or Perform the calculation: in, R orb This is the resistance value of the second standard resistor; U or0 The voltage value measured by the background potential test module before receiving the start internal resistance test command; U orb The voltage value measured by the background potential test module after receiving the start internal resistance test command; The second internal resistance calculation block transmits the calculation results to the zirconia analyzer out-of-tolerance test module via the fifth signal line; After the second relay and the second internal resistance calculation block receive the stop internal resistance test command sent by the zirconia analyzer out-of-tolerance test module through the fifth signal line, the common terminal of the two docking points of the second relay is disconnected from its normally open contact, and the two ends of the second standard resistor are disconnected from the positive signal input line and the negative signal input line of the zirconia sensor, respectively.

6. The zirconia analyzer out-of-tolerance testing module according to claim 1, characterized in that: The zirconia analyzer out-of-tolerance testing module also receives the oxygen signal from a second zirconia analyzer via the thirteenth signal line. The second zirconia analyzer is installed on the same process pipeline near this zirconia analyzer. The zirconia analyzer out-of-tolerance testing module contains a timing operation block. The first internal resistance testing module measures the resistance of the temperature sensor as follows: R T The second internal resistance testing module measured the internal resistance of the zirconia sensor to be... Ro The background potential test module measured the background potential of the zirconia sensor to be: E 0. The zirconia analyzer out-of-tolerance test module receives the oxygen signal from the second zirconia analyzer via the thirteenth signal line. X 2. The zirconia analyzer's out-of-tolerance test module receives the oxygen signal sent by the oxygen measurement and calculation control module. X 1; The out-of-tolerance logic operation of the out-of-tolerance test module of the zirconia analyzer is as follows: If any of the following conditions are met, the zirconia analyzer will be considered out of tolerance, and the out-of-tolerance test module will issue an out-of-tolerance alarm: ① Internal resistance of the zirconium oxide sensor Ro ≥a, where a is the probe internal resistance limit of the zirconia sensor that does not exceed the tolerance; ② Absolute value of the resistance change of the temperature sensor | R T - R T0 |≥η, R T0 η is the initial value of the internal resistance of the temperature sensor, and η is the resistance variation limit of the temperature sensor that does not exceed the tolerance. ③ Absolute value of the background potential change of the zirconia sensor | E 0- E 00 |≥θ, E 00 θ is the initial value of the zirconia sensor's base potential, and θ is the allowable drift value of the zirconia sensor's base potential within tolerance. ④︱ X 1- X 2︱≥m, where m is the limit of the difference between the oxygen value measured by the oxygen measurement and calculation control module and the oxygen value measured by the second zirconia analyzer; a, R T0 ,η, E 00 θ and m are stored in the memory inside the out-of-tolerance testing module of the zirconia analyzer.

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