Gas-electricity meter based on parameter compensation calibration multi-channel high-speed measurement method

Abstract

The gas electricity quantity appearance based on the parameter compensation calibration multi-channel high-speed measurement method provided by the application, the measurement steps comprise: collecting the temperature and humidity of a workpiece, the gas source pressure and the pressure difference signal of the measuring head through multiple acquisition channels; processing the collected signals; based on the collected signals, the pressure difference signal is calibrated through the gas source pressure and pressure difference compensation algorithm; based on the compensated pressure difference signal, the pressure difference signal is converted into corresponding workpiece size through the pressure difference size page conversion algorithm; based on the converted size data, the temperature and size compensation algorithm is used to calibrate the size data at different temperatures, and the real-time data of the workpiece is accurately measured.

Description

TECHNICAL FIELD

[0001] The present application relates to a testing device, in particular to a gas-electric quantity meter based on a parameter compensation calibration multi-channel high-speed measurement method. BACKGROUND

[0002] More and more parts of the processing detection tend to be intelligent and digital; but in the traditional production management, there are obvious deficiencies in quality supervision: first, most enterprises still use manual measurement and adopt sampling inspection, which is time-consuming and laborious, and it is difficult to ensure measurement accuracy, which is easy to cause quality problems; second, there is a lack of data storage management persistence, and quality data is not analyzed, it is difficult to find production problems in time, which is easy to cause a large amount of property loss for enterprises.

[0003] The gas-electric quantity meter is a new type of measuring tool, which uses gas as the measuring medium, converts the length signal into the gas flow signal, and further converts it into the electric signal through the gas-electric converter, and then carries out comparison measurement. The principle of gas-electric measurement is based on fluid dynamics and fluid statics, and the structure and physical size of the workpiece are measured according to the pressure characteristics and flow characteristics of compressed air. Due to the characteristics of using gas as the measuring medium, the gas-electric quantity meter can measure more items, has less human error, and the measuring head does not directly contact the measured surface, so it can become one of the main instruments for high-precision measurement.

[0004] The currently used gas-electric quantity meter mainly has the following problems: (1) It is easily affected by environmental factors such as unstable gas source pressure, temperature and humidity changes, etc., causing unstable workpiece size measurement precision; (2) The sampling precision and sampling rate are not enough, resulting in too few data samples, affecting the size measurement precision; (3) The differential pressure-size conversion adopts linear conversion, which cannot adapt to the nonlinear relationship between actual differential pressure and size, causing measurement error. SUMMARY

[0005] In order to overcome the deficiencies of the prior art, the present application provides a gas-electric quantity meter based on a parameter compensation calibration multi-channel high-speed measurement method.

[0006] In order to achieve the above purpose, the present application provides a gas-electric quantity meter based on a parameter compensation calibration multi-channel high-speed measurement method, which comprises a collection module, a signal processing module and a control module, and the parameter compensation calibration multi-channel high-speed measurement method specifically comprises the following steps:

[0007] The temperature and humidity, gas source pressure and probe pressure difference signals of the workpiece are collected through multiple collection channels; and the collected signals are processed;

[0008] Based on the collected signals, the pressure difference signal is calibrated through a gas source pressure and pressure difference compensation algorithm;

[0009] Based on the compensated differential pressure signal, the differential pressure signal is converted into corresponding workpiece size through a differential pressure size page conversion algorithm;

[0010] Based on the converted size data, a temperature and size compensation algorithm is used to calibrate size data at different temperatures.

[0011] Preferably, the steps of the gas source pressure and differential pressure compensation algorithm include:

[0012] Calculate the gas source pressure and differential pressure compensation value: compensate the differential pressure with the gas source pressure and humidity as parameters, and the relationship between the gas source pressure, humidity and differential pressure is:

[0013] △DP=f(Gsp,H)

[0014] Where Gsp is the gas source pressure, △DP is the differential pressure compensation value, H is the current humidity, Gsp and △DP are in a polynomial relationship, H and △DP-Gsp curve are in an interval relationship, and f is a polynomial function of gas source pressure Gsp and differential pressure compensation value △DP in a specified temperature interval;

[0015] Determine the current humidity: if the current humidity exceeds the set humidity, prompt that the humidity is too large and needs to be confirmed; if the current humidity is less than the set humidity, determine the interval of the △DP-Gsp compensation curve corresponding to the current humidity, call the fitting coefficient of the △DP-Gsp compensation curve in the corresponding interval to compensate the differential pressure with the gas source pressure, and the calculation formula is:

[0016] ΔDP=f(Gsp)=a6*Gsp 6 +a5*Gsp 5 +a4*Gsp 4 +a3*Gsp 3 +a2*Gsp 2 +a1*Gsp+a0;

[0017] Where the gas source pressure Gsp compensates the differential pressure compensation value △DP using a multi-order polynomial fitting curve, and α 0～6 is a multi-order polynomial compensation coefficient, which is obtained through a corresponding compensation coefficient acquisition algorithm;

[0018] The current real-time differential pressure is compensated using the differential pressure compensation value, and the compensated real-time differential pressure is obtained, and the formula is:

[0019] DP=DP c +DDP;

[0020] Where DP is the compensated real-time differential pressure, DP c is the real-time differential pressure of each channel, and △DP is the differential pressure compensation value obtained by compensating the differential pressure with the gas source pressure using a polynomial fitting conversion.

[0021] Preferably, the air source pressure and differential pressure compensation coefficient acquisition algorithm, the specific steps for acquiring the compensation coefficient include:

[0022] Timing to obtain the current environment real-time humidity;

[0023] Determine whether the current environment humidity is in the selected humidity interval, if yes, proceed to the next step, otherwise prompt the user to adjust the environment humidity or modify the humidity interval;

[0024] If the current humidity meets the requirements, prompt the user to put in the standard part, input the standard part size value and the probe model, and obtain the calibration data bound to the standard part size and the probe model;

[0025] According to the set standard air source pressure, divide the calibration interval, obtain the air source pressure value and the differential pressure value in all calibration intervals, adjust the air source pressure to the standard pressure, and acquire the air source pressure and differential pressure compensation calibration coefficient for the current humidity. The compensation calibration is performed by fitting a one-dimensional polynomial, and the fitting coefficient is obtained by the least square method. The differential pressure and the air source pressure are a one-dimensional six-order polynomial function relationship;

[0026] If the humidity interval is switched and the calibration coefficient is re-fitted and obtained before switching, save the current humidity interval calibration fitting coefficient, pop up the fitting coefficient saving dialog box, and select to save the fitting coefficient before switching the humidity interval;

[0027] After saving the fitting coefficient, prompt the user to adjust the calibration environment humidity, adjust the current environment humidity to the set humidity interval; repeat the above steps to obtain the air source pressure and differential pressure compensation calibration coefficient corresponding to the set humidity interval.

[0028] Preferably, the specific steps of the differential pressure size page conversion algorithm for differential pressure size conversion include:

[0029] Page the differential pressure value, put the standard part into the specified position, obtain the corresponding differential pressure value, based on the current differential pressure value, turn the current pressure value page to the corresponding page, and fill the current differential pressure value into the corresponding value item; if the differential pressure values between pages are equal at the beginning and the end, execute the next step;

[0030] The differential pressure and size adopt a multi-order polynomial conversion, and the formula is:

[0031] SV i = b 6i *DP 6 + b 5i *DP 5 + b 4i *DP 4 + b 3i *DP 3 + b 2i *DP 2+b 1i *DP+b i ;

[0032] Wherein, SV i is the real-time size after corresponding page conversion, b 6i , b 5i , b 4i , b 3i , b 2i , b 1i , b i is the polynomial fitting coefficient of corresponding page, obtained by corresponding differential pressure size conversion coefficient obtaining algorithm, DP is the real-time differential pressure after compensation by gas source pressure.

[0033] Preferably, the steps of the differential pressure size conversion coefficient obtaining algorithm comprise:

[0034] Obtaining the real-time differential pressure value and the input differential pressure value, judging whether the current differential pressure value is within the set range, if yes, filling the current differential pressure value into the differential pressure value of the corresponding calibration item;

[0035] According to the starting item and the end item size value and the total number of calibration items, dividing the size value of the differential pressure, obtaining all calibration size reference values of the current page and correcting the reference values;

[0036] Selecting the size value of the corresponding calibration item, while the user places the corresponding standard part according to the selected calibration item size value, and fills in the actual size value which is less than the size value of the previous calibration item and greater than the size value of the next calibration item in the interface;

[0037] If all the size values of the standard parts and the corresponding differential pressure values of the current page meet the requirements, calibration is started, if there are modification items in each differential pressure and size input value, save the modification item data, obtain the size value by multi-order polynomial function calculation, perform least square fitting on the size values and the corresponding differential pressure values of all groups of the current page, obtain the coefficients corresponding to the corresponding multi-order polynomial function, and display the calibration coefficients in the interface;

[0038] Performing page conversion operation in the differential pressure size conversion coefficient obtaining interface, the conversion page operation comprises: adding page, deleting page, turning up page, turning down page operation.

[0039] Preferably, the compensation steps of the temperature and size compensation algorithm comprise:

[0040] Judging whether the current temperature is within the temperature range set in the temperature and size value compensation coefficient obtaining algorithm, if yes, calling the temperature and size value compensation coefficient obtaining algorithm to perform polynomial calculation and obtaining the calibration size value after temperature compensation;

[0041] If the current temperature exceeds the set range and the number of times of exceeding the threshold is greater than the set value, an alarm is prompted.

[0042] The specific calculation steps of the compensation coefficient acquisition algorithm of the temperature and size value are preferably as follows:

[0043] The size values of the workpiece at different temperatures are obtained, and a one-dimensional polynomial function of temperature relative to size value is obtained by fitting the obtained multiple sets of data using the least square method.

[0044] The gas-electricity meter based on the parameter compensation calibration multi-channel high-speed measurement method provided by the application has the beneficial effects that:

[0045] The gas-electricity meter based on the parameter compensation calibration multi-channel high-speed measurement method provided by the application has the beneficial effects that: BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 The flowchart of the gas-electricity meter based on the parameter compensation calibration multi-channel high-speed measurement method provided by the application is provided.

[0047] Figure 2 The principle block diagram of the gas-electricity meter system based on the parameter compensation calibration multi-channel high-speed measurement method provided by the application is provided.

[0048] Figure 3 The cross-sectional view of the probe structure in the high-precision multi-size synchronous measurement gas-electricity meter provided by the application is provided.

[0049] Figure 4 The schematic diagram of the probe structure and the differential pressure sensor connection measurement in the high-precision multi-size synchronous measurement gas-electricity meter provided by the application is provided.

[0050] Figure 5 The flowchart of the gas-electricity meter based on the parameter compensation calibration multi-channel high-speed measurement method provided by the application is provided.

[0051] Figure 6 The flowchart of the gas-electricity meter based on the parameter compensation calibration multi-channel high-speed measurement method provided by the application is provided.

[0052] Figure 7 The flowchart of the gas-electricity meter based on the parameter compensation calibration multi-channel high-speed measurement method provided by the application is provided.

[0053] Figure 8 In the gas electricity quantity meter based on the parameter compensation calibration multi-channel high-speed measurement method provided by the present application, the flowchart of page conversion for obtaining the differential pressure size conversion coefficient on the touch screen is shown in the figure;

[0054] Figure 9 In the gas electricity quantity meter based on the parameter compensation calibration multi-channel high-speed measurement method provided by the present application, the man-machine interaction interface schematic diagram for realizing page switching of the differential pressure size conversion coefficient is shown in the figure. DETAILED DESCRIPTION

[0055] The embodiments of the present application will be described in detail below with specific specific examples, and other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure of the present specification. The present application can also be implemented or applied by different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the following examples and features in the examples can be combined with each other without conflict.

[0056] As shown in Figure 1 The present application provides a gas electricity quantity meter based on a parameter compensation calibration multi-channel high-speed measurement method, which comprises a collection module, a signal processing module and a control module (main MCU), and the parameter compensation calibration multi-channel high-speed measurement method specifically comprises the following steps:

[0057] The temperature and humidity, gas source pressure and probe differential pressure signals of the workpiece are collected through multiple collection channels; and the collected signals are processed;

[0058] Based on the collected signals, the differential pressure signal is calibrated through a gas source pressure and differential pressure compensation algorithm;

[0059] Based on the compensated differential pressure signal, the differential pressure signal is converted into corresponding workpiece size through a differential pressure size page conversion algorithm;

[0060] Based on the converted size data, a temperature and size compensation algorithm is used to calibrate the size data at different temperatures.

[0061] Specifically, the present application adopts multiple sensors to realize the collection of temperature and humidity, gas source pressure and multi-channel pressure difference signals through multiple collection channels, and then performs signal adjustment and filtering processing on the collected signals. In view of the influence of environmental factors such as temperature and humidity and gas pressure on the workpiece size test result, through the compensation algorithm of gas source pressure and humidity on pressure difference and the compensation algorithm of temperature on workpiece size, temperature, humidity and gas pressure are taken as environmental variables for nonlinear fitting to obtain a polynomial calibration function to calibrate the actual measured size data, so as to realize accurate size measurement under different environments. In view of the nonlinear situation of pressure difference-size conversion, and in order to improve the conversion accuracy of pressure difference-size, a paging conversion method is adopted to segment the measurement interval, and the corresponding polynomial conversion algorithm is adopted to fit and convert the pressure difference data into size signals, thereby improving the measurement efficiency. In addition, during conversion, the measurement interval is increased, deleted, and jumped, etc., further improving the flexibility of pressure difference-size conversion.

[0062] As shown in Figure 2 The system of the gas-electricity meter includes a probe module, a workpiece pressure difference collection signal processing module, a gas source pressure collection signal processing module, a main MCU, a temperature and humidity collection module, a touch screen for realizing man-machine interaction, a power supply module and a slave MCU. The temperature and humidity sensing module is connected with the main MCU through an IIC bus, and the touch screen for realizing man-machine interaction communicates with the main MCU through a serial port. The workpiece pressure difference collection signal processing module and the gas source pressure collection signal processing module are used for receiving gas source signals and pressure difference signals, and the received signals are converted and sent to the main MCU through an FMC parallel bus for compensation operation. The power supply module is used for supplying power to the system of the gas-electricity meter. The slave MCU is used for sending raw data waveform display data to the touch screen, communicating through a serial port, and checking some sudden signals of the current workpiece measurement channel data through the raw data waveform. The system main MCU sends real-time size and real-time scatter of each channel to the touch screen through a serial port and displays the same through a waveform on a data interaction interface. The data is sent separately through the double MCUs, thereby reducing the processing pressure of the main MCU and improving the processing capacity of the main MCU on real-time size. The collection module includes a temperature and humidity sensing module and a probe module; the signal processing module includes a workpiece pressure difference collection signal processing module and a gas source pressure collection signal processing module, and the control module is the main MCU.

[0063] The temperature and humidity collection module is composed of multiple temperature and humidity sensors. The probe module includes a pressure difference sensor collection and a probe. The pressure difference signal is the pressure difference value of the gas source pressure after the pressure stabilizing valve and the pressure at the probe nozzle collected by the pressure difference sensor at the probe. The probe needs to select appropriate probe form and appropriate probe size according to the structure and position of the measured part, so that the change relationship between the pressure difference and the gap during measurement is approximately linear, so that the measurement result is more accurate. As shown in Figure 3 the cross-sectional view of the probe structure; asFigure 4 The diagram shows a schematic of the probe structure connected to a differential pressure sensor for measurement. In the diagram, 1 is the pressure-stabilizing chamber, 2 is the throttling orifice, 3 is the back pressure chamber, 4 is the nozzle-baffle mechanism, and 5 is the differential pressure sensor. Wherein, Pb is the gas source pressure, Px is the gas pressure at the nozzle, d1 is the orifice diameter, d is the nozzle diameter, and x is the gap between the workpiece and the probe.

[0064] In this invention, when processing the acquired signal, the differential pressure analog signal is first proportionally adjusted so that the output analog signal conforms to the voltage conversion range of the analog-to-digital converter; then, a low-pass filter is used to filter out high-frequency interference signals in the output signal; subsequently, an 8-channel 18-bit synchronous sampling ADC is used for acquisition, and multi-channel synchronous conversion of the analog signal is achieved through a parallel FMC bus. During multi-channel acquisition, each channel independently acquires the gas source pressure.

[0065] The workpiece differential pressure acquisition signal processing module is designed to convert the analog signal from the differential pressure sensor into a digital signal that can be processed by the main MCU. This module includes cascaded operational amplifiers, filtering circuits, and multiple high-precision analog-to-digital converters (ADCs). The operational amplifiers proportionally adjust the differential pressure analog signal to ensure the output signal conforms to the voltage conversion range of the ADC. The filtering circuits are low-pass filters used to remove high-frequency interference signals from the operational amplifier output signal. The multiple high-precision ADCs employ an 8-channel 18-bit synchronous sampling ADC, using a parallel FMC bus to achieve multi-channel synchronous conversion of the analog signal, providing the main MCU with abundant raw data.

[0066] The air source pressure acquisition and processing module and the workpiece differential pressure acquisition and processing module perform the same function: converting the analog air source pressure signal into a digital signal that can be processed by the main MCU. To improve the accuracy of the dimension measurement for each channel, the air source pressure for each channel is acquired separately and calibrated using an air source pressure-differential pressure calibration algorithm.

[0067] When collecting environmental data, data is acquired via the IIC bus, with a timer set to the measurement refresh cycle. Temperature and humidity are acquired once the measurement refresh cycle is reached. Air pressure is also collected for each air source to ensure the accuracy of differential pressure compensation. Simultaneously, air pressure for each air source is acquired via the FMC parallel bus, using the same method as the instantaneous differential pressure value acquisition method described above.

[0068] like Figure 5 As shown, for differential pressure acquisition, an 8-channel, 18-bit synchronous AD7609 sampling chip is used to realize the analog-to-digital conversion of the differential pressure signal, and the 8-channel sampling data converted by AD7609 is obtained through the parallel bus FMC.

[0069] The data collection steps include:

[0070] S1.0: Stop AD7609 sampling operation: set the analog-digital conversion start IO level to high, and turn off the analog-digital conversion IO output PWM control timer.

[0071] S1.1: Configure AD7609 conversion completion detection BUSY signal, and disable the external interrupt of the BUSY signal. After the AD7609 completes the conversion, it will output a falling edge signal through the BUSY pin, and the MCU will capture the signal through the external interrupt.

[0072] S1.2: AD7609 reset operation: the main MCU outputs a high-level pulse with a duration of not less than 50nS to the RESET pin connected to the AD7609, and sets the hardware to low level after the pulse output is completed.

[0073] S1.3: Output a low-level pulse to the AD7609 analog-digital conversion start port, which can start the AD7609 for an AD conversion, avoiding the first data obtained from the AD7609 being 0.

[0074] S1.4: Clear the relevant variables in the differential pressure sampling value data FIFO storage structure variable. Differential pressure sampling data storage is performed through two structure variables. Among them, FIFO (First In First Out) is a kind of first-in first-out data buffer, which is used to realize the ordered storage and reading of data.

[0075] One of the structure variables is an 8-channel single sampling data storage variable, which contains 8-channel AD conversion data. Single-channel data is divided into two 16-bit data, so it includes 16-element 16-bit arrays and 16-element 32-bit arrays.

[0076] The other structure variable is a FIFO operation structure variable stored according to the number, which includes a data storage FIFO array, an array read data position variable, an array write data position variable, an array storage data number variable, and a FIFO full flag.

[0077] S1.5: Configure the AD7609 analog-digital conversion chip to work in automatic acquisition mode.

[0078] First, configure the PWM pulse output timer of the main MCU to output PWM pulses to the AD7609 start conversion port. The pulse frequency is calculated according to the user-set instantaneous sampling number and measurement refresh rate, pulse frequency = instantaneous sampling number * measurement refresh rate. The measurement refresh rate is the number of calculation and display of size data per unit time 1S, and the instantaneous sampling number is the number of 8-channel synchronous differential pressure sampling in the measurement refresh period. Finally, set and enable the conversion completion detection BUSY interrupt signal.

[0079] After the multi-channel differential pressure acquisition setup is completed, the main MCU timer will send high-frequency PWM pulses to the start conversion port of the AD7609 in a timely manner. The 8-channel synchronous AD conversion speed of the AD7609 can reach up to 200 kHz. After each conversion is completed, the BUSY port of the AD7609 will generate a falling edge signal, and the main MCU will obtain the falling edge through an external interrupt.

[0080] Based on the external interrupt, it is determined whether the AD7609 has completed conversion. If so, the multi-channel sampling data reading, conversion, and storage process is performed to achieve differential pressure data acquisition, and the steps are as follows:

[0081] S1.6: 8-channel single sampling data corresponding to the address is obtained in sequence through the FMC bus, each data occupies 18 bits, and 2 16-bit array elements are used for storage. D[17:2] in the 18-bit data is stored in the first array element sNowAdc[0], and D[1:0] is stored in the high bit of the second array element sNowAdc[1]. Therefore, the array has a total of 16 elements for storing 8-channel differential pressure data.

[0082] S1.7: The 16 elements of the array are processed. The 2 elements corresponding to each data are converted into 32-bit data and subjected to a shift operation, specifically: sNowAdc[0]*4+sNowAdc[0] / 16384. The corresponding 8 data are stored in an array containing 8 elements.

[0083] S1.8: The 8 data in the 8-channel differential pressure storage array are stored in the corresponding positions of the FIFO array in the FIFO operation structure. The FIFO operation structure includes a write data position variable. Each time a data is written, the position variable is incremented by 1. If the variable is greater than the FIFO size, the variable is reset to zero, thereby realizing cyclic writing in the FIFO. In addition, the FIFO operation structure includes a variable for recording the number of unread data in the FIFO array. Each time a data is written into the FIFO, the variable is also incremented by 1. If the variable is greater than the FIFO size, the FIFO full flag in the FIFO operation structure is set to 1.

[0084] The AD7609 start conversion port receives the PWM pulse sent by the MCU in a timely manner. The MCU will acquire the differential pressure signal according to the PWM pulse frequency. The system main loop determines whether the number of sampling data reaches the system set instantaneous sampling number in real time. If so, the multi-channel data extraction and single cycle data processing process is performed. At the same time, if the user does not press the stop detection button, the AD7609 sampling data acquisition continues.

[0085] The system sets a period acquisition data flag and two FIFO operation structures to store AD7609 sampling data. In odd periods, the data is stored in the FIFO array in the FIFO1 structure, and in even periods, the data is stored in the FIFO array in the FIFO2 structure. At the same time, the data in the FIFO2 structure sampled in the odd period is extracted, and the data in the FIFO operation structure sampled in the even period is extracted, so that the differential pressure data is collected and synchronized at the same time, improving the data processing efficiency and the size measurement accuracy.

[0086] After a single data sampling is completed, a differential pressure data in the FIFO operation structure is taken out for judgment. Whether it is greater than the trigger range value set by the user in the measurement setting interface is judged. If the workpiece is not placed or the workpiece is not placed according to the requirement, the differential pressure threshold number variable is operated by 1. In the next round of measurement refresh period, the differential pressure data is judged again. If the differential pressure is in the trigger range, the differential pressure threshold number variable is cleared, whether the differential pressure threshold number is greater than the set value is judged. If yes, the system alarms and ends the real-time measurement process, and waits for the user to place the workpiece and click “measurement” to start measurement.

[0087] The specific steps of the multi-channel data extraction and single period data processing flow include:

[0088] S1.9: Extract all unextracted data in the FIFO operation structure array in the corresponding period. The differential pressure storage array in the FIFO operation structure is stored in the FIFO form, that is, the data stored first is kicked out of the array after the array is full.

[0089] S1.10: Calculate the standard deviation of the extracted data. The standard deviation calculation formula is:

[0090]

[0091] Where N is the number of data, x i is the corresponding position data in the array, is the average value of all data in the array. According to the normal distribution characteristics of data, 3σ is used for outlier rejection, and all data outside the range of x±3σ is rejected.

[0092] S1.11: Calculate the mean value of the rejected data, and store the calculated mean value in the differential pressure measurement storage array and record the storage number.

[0093] S1.12: The data processed in a single period is stored in the differential pressure measurement storage array in turn. When the data in the array reaches the differential pressure real-time data processing number, the data in the array is processed. After the data is processed by the Gaussian filter method, the mean value is obtained, and the differential pressure value is the real-time differential pressure at the current time.

[0094] After the completion of the current round of sampling and data processing, all variables of the current round of sampling are cleared, and the next round of data sampling and processing is restarted, thereby ensuring the independence of the next and current data.

[0095] In single round data collection and processing, a single cycle large data collection method is used to obtain a large amount of data, and the mean value processing is used to obtain the instantaneous differential pressure value; the data of a specified single cycle number is processed to obtain a relatively stable real-time differential pressure value; the cycle of the single cycle and the cycle number data variable can be adjusted, which is convenient for parameter adjustment according to the environment, thereby improving the measurement accuracy.

[0096] In this embodiment, based on the collected differential pressure, gas source pressure and temperature and humidity data, the influence of the gas source pressure on the differential pressure is compensated by using the gas source pressure and differential pressure compensation algorithm, and the steps include:

[0097] Calculate the gas source pressure (humidity) and differential pressure compensation value:

[0098] S2.0: The change of the gas source pressure will affect the actual differential pressure value, and the humidity will affect the gas source pressure, so the gas source pressure and humidity are used as parameters for differential pressure compensation. The relationship between the gas source pressure, humidity and differential pressure is:

[0099] △DP=f(Gsp,H),

[0100] Where Gsp is the gas source pressure, △DP is the differential pressure compensation value, H is the current humidity, Gsp and △DP are in a polynomial relationship, H and △DP-Gsp compensation curve are in an interval relationship, and f is a polynomial function of gas source pressure Gsp and differential pressure compensation value △DP in a specified temperature interval.

[0101] S2.1: First, determine the current humidity, if the humidity exceeds the system set humidity, the system prompts that the humidity is too large, the user needs to confirm, otherwise, further determine the interval of the current humidity corresponding to the △DP-Gsp compensation curve, call the fitting coefficient of the △DP-Gsp compensation curve in the corresponding interval to compensate the differential pressure of the gas source pressure, and the calculation formula is:

[0102] ΔDP=f(Gsp)=a6*Gsp 6 +a5*Gsp 5 +a4*Gsp 4 +a3*Gsp 3 +a2*Gsp 2 +a1*Gsp+a0;

[0103] Where the compensation of Gsp to the differential pressure compensation value △DP is compensated by a 6-order polynomial fitting curve, and α 0～6The compensation coefficient of the multi-order polynomial is obtained by the compensation coefficient acquisition algorithm corresponding to the air source air pressure (humidity) - differential pressure.

[0104] S2.2: After obtaining the differential pressure compensation value ΔDP, the current real-time differential pressure is compensated to obtain the compensated real-time differential pressure, and the formula is:

[0105] DP = DP c + DDP.

[0106] Wherein, DP is the compensated real-time differential pressure, DP c is the real-time differential pressure of each channel obtained by the real-time differential pressure acquisition process, and ΔDP is the differential pressure compensation value obtained by converting the differential pressure compensation polynomial corresponding to the air source air pressure.

[0107] In the application, different humidity will affect the change of the air pressure at both ends of the differential pressure sensor, and then affect the collection of the final sensor differential pressure value, therefore, the differential pressure compensation is required for different humidity. From the influence of air pressure on differential pressure, the differential pressure is a binary polynomial function of air source air pressure and environmental humidity, considering the influence weight of humidity and air source air pressure on air pressure, the humidity influence weight is low, in order to reduce the humidity collection frequency and reduce the difficulty of environmental humidity setting, the humidity is calibrated in intervals in the calibration, the constant humidity environment of different humidity is set, and then the compensation calibration of different air source air pressure is carried out.

[0108] Wherein, when the compensation coefficient corresponding to the air source air pressure and the differential pressure is obtained, if the size deviation of the workpiece to be measured and the current calibrated workpiece size is large, the air source air pressure compensation calibration process of the differential pressure is re-performed (that is, the above steps are repeated), if the deviation is small, the coefficient compensation algorithm is used for calibration, as shown in Figure 6 The specific steps include:

[0109] S2.10: The current environmental humidity is acquired in time, and the humidity is taken out for use when the current process is executed.

[0110] S2.11: It is judged whether the current environmental humidity is in the selected humidity interval, if yes, the next step is carried out, otherwise the user is prompted to adjust the environmental humidity or modify the humidity interval.

[0111] In the embodiment, the humidity interval is divided into four grades, which are 30% to 40%, 40% to 50%, 50% to 60%, and 60% to 70%, and lower than 30% or higher than 70%, the alarm is given, and the user is prompted that the current environmental humidity is abnormal, and the equipment cannot work normally.

[0112] S2.12: If the humidity meets the requirements, prompt the user to put in the standard part and input the standard part size value, and input the probe model in the current calibration interface. The final calibration data obtained will be bound with the standard part size and the probe model. When the user sets the measurement, the user can select the compensation coefficient of the air pressure (humidity) to the differential pressure of each channel size measurement according to the actual probe model and the measured part size value.

[0113] S2.13: Adjust and obtain the air source pressure.

[0114] Adjust according to the set standard air source pressure, obtain the current differential pressure value. In this embodiment, the set standard air source pressure is preferably 0.3 MPa. In order to ensure the accuracy of calibration, the air source pressure calibration interval is divided according to the standard air source pressure, the air source pressure calibration starting pressure and the air source pressure calibration ending pressure. In this embodiment, a total of 20 calibration intervals are divided. The starting pressure to the standard air source pressure is divided into 10 calibration intervals, and the standard air source pressure to the ending pressure is divided into 10 calibration intervals.

[0115] S2.14: The above 10 intervals are sequentially subjected to air source pressure collection and corresponding differential pressure collection and recording.

[0116] The user selects one of the intervals each time to collect the corresponding air source pressure. The user adjusts the pressure of the pressure stabilizing valve input to the air source pressure to the range of the currently selected pressure interval, and then selects the "input pressure" button in the interface to complete the collection of the air source pressure in this interval. At this time, the differential pressure value of the current channel is obtained and recorded.

[0117] S2.15: After completing the collection of air source pressure and corresponding differential pressure in all intervals, adjust the air source pressure to the standard air source pressure. The air pressure has high precision requirement and the error requirement is within 0.1%, so as to ensure the accuracy of the reference air pressure. After the "input pressure" button is pressed, the air source pressure is compared with the standard pressure. If the error is greater than 0.1% (which can be set), the user is prompted to adjust the air source pressure again until the error requirement is met. After the air source pressure input is completed, the current channel differential pressure value is obtained in real time and recorded.

[0118] S2.16: After completing the collection of all air source pressure and differential pressure values, the air source pressure-differential pressure compensation calibration coefficient of the current humidity can be obtained. The compensation calibration is performed by fitting a one-dimensional polynomial. The fitting coefficient is obtained by the least square method. The differential pressure and the air source pressure are a one-dimensional six-order polynomial function relationship.

[0119] S2.17: If the user performs humidity interval switching, and the calibration coefficient refitting is performed before switching, the current humidity interval calibration fitting coefficient saving process is performed, the fitting coefficient saving dialog box is popped up, and the fitting coefficient before switching the humidity interval is saved according to the user selection. After the fitting coefficient saving process is completed, the user is prompted to adjust the calibration environment humidity, and the current environment humidity is adjusted to the set humidity interval. Then, the corresponding humidity interval gas source pressure-differential pressure compensation calibration coefficient is obtained according to the above method.

[0120] S2.18: If the "Exit" button is clicked, the current humidity interval calibration fitting coefficient saving process is performed, and then the interface is exited.

[0121] In this embodiment, after the gas source pressure (humidity)-differential pressure compensation value calculation is completed, the compensated differential pressure is converted into a corresponding size value. The differential pressure-size value conversion is performed in a paging conversion manner, and the steps include:

[0122] S3.0: The differential pressure value is paged, the standard part is placed in the specified position, the corresponding differential pressure value is obtained, the current pressure value difference page is turned to the corresponding page based on the current differential pressure value, and the current differential pressure value is filled into the corresponding numerical item. If the differential pressure values between each page are equal at the beginning and the end (i.e., the maximum differential pressure value of the previous page is equal to the minimum differential pressure value of the current page, and the maximum differential pressure value of the current page is equal to the minimum differential pressure value of the next page, thereby ensuring that the current real-time differential pressure value is within the differential pressure conversion range established by the user), the next step is performed.

[0123] S3.1: The differential pressure-size conversion adopts a 6-order polynomial conversion, and the formula is:

[0124] SV i = b 6i *DP 6 + b 5i *DP 5 + b 4i *DP 4 + b 3i *DP 3 + b 2i *DP 2 + b 1i *DP + b i ;

[0125] wherein SV i is the real-time size after conversion of the corresponding page, b 6i , b 5i , b 4i , b 3i , b 2i , b 1i , b iThe polynomial fitting coefficient corresponding to the page is obtained by the differential pressure size conversion coefficient algorithm, different channel coefficients are used for polynomial calculation, and the DP is the real-time differential pressure compensated by the gas source pressure. It should be noted that the order of the polynomial can be set according to the actual application scene.

[0126] In the application, the differential pressure size conversion algorithm realizes the accurate conversion coefficient acquisition of the corresponding differential pressure to the size value in each page by adopting multiple workpieces for page calibration in each channel, and performing polynomial fitting on each page data. At the same time, when the page calibration setting is performed, the last size value of the previous page and the first size value of the current page are ensured to be the same, so as to ensure the uninterrupted interval of calibration.

[0127] As shown in Figure 7 The specific steps of the differential pressure size conversion coefficient acquisition algorithm include:

[0128] S3.10: Before calibration in each channel, the size value input of each standard part and the acquisition of the corresponding differential pressure value are completed, and the polynomial coefficient of the conversion between the differential pressure and the size value is realized by polynomial fitting of multiple sets of differential pressure values and corresponding standard part sizes.

[0129] In the calibration interface, the differential pressure value of the current user selected channel is acquired in real time and displayed in the interface. At this time, the user can click the "input differential pressure" button, and the system judges whether the current differential pressure indication value is within the set range. If yes, the current differential pressure indication value is filled in the differential pressure value of the corresponding calibration item. The differential pressure set range filled in the calibration item is to ensure the accuracy of calibration. The differential pressure sensor is converted by the sampling chip with model AD7609 and input to the main MCU as 18-bit data. Among them, the highest bit is the sign bit, and the range of data after removing the sign bit is 0-131071. Generally, the conversion accuracy of the differential pressure size conversion is higher in the middle value of the data, so the differential pressure set range can be set to 30000-60000. If it exceeds the range, it prompts the user to reset the range or adjust the equipment to obtain the differential pressure value in the range.

[0130] S3.11: A fast size value division method is used. After the user clicks the "size value division" button, the starting item and the end item size value and the total number of calibration items are equally divided to obtain all calibration size reference values in the page, so as to realize the fast input of the standard part size. After the size is divided, the size value obtained by automatic division can be modified.

[0131] S3.12: When the user selects the size value of the corresponding calibration item, the system prompts the user to place the corresponding size standard part according to the size value of the item, and fill in the actual size of the current standard part in the interface.

[0132] In order to ensure the correctness of the user input data and the final fitting coefficient, the user input standard part size is constrained, and it is required that the current filled standard part size must be smaller than the size value of the previous calibration item and larger than the size value of the next calibration item. If this requirement is not met, the user is prompted to re-fill the standard part size value.

[0133] S3.13: After all the standard part size values and corresponding pressure difference values on the page are input and meet the set requirements, the calibration coefficient acquisition can be started.

[0134] The user clicks the "start calibration" button, and judges whether there are modification items for each pressure difference and size input value. If there are, the modification item data is stored. The size and pressure difference are in a six-order polynomial relationship, wherein the pressure difference is the input parameter, and the size value is calculated through a six-order polynomial function. The least square method is used to fit all the size values and corresponding pressure difference values on the page to obtain the coefficients of the corresponding six-order polynomial function, which are displayed on the interface.

[0135] S3.14: In the pressure difference-size conversion coefficient acquisition interface, page conversion operations are performed, including adding pages, deleting pages, flipping up pages, and flipping down pages, as shown in Figure 8 It should be noted that when performing page conversion operations, the first and last pressure difference values between pages must be equal to ensure continuity between pages.

[0136] The specific switching operation steps include:

[0137] (1) If the "previous page" button is clicked, it is first judged whether the current page is the first page. If it is, the user is prompted that it is the first page, otherwise the calibration page switching process is executed.

[0138] It is first judged whether there are calibration parameter modifications in the current page. If there are, a parameter saving dialog box is popped up, and the calibration parameters are saved according to the user's selection. It is then judged whether the calibration coefficients are updated. If there are updated coefficients, the calibration coefficients are saved. Here, the calibration parameters and calibration coefficients are stored in temporary variables when entering the interface. When the user exits the page, the current parameters can be compared with the parameters stored in the temporary variables to determine whether the parameters have been modified.

[0139] (2) After the calibration parameters and calibration coefficients are saved, the current page record variable is reduced by 1, and the calibration parameters and calibration coefficients of the current page are obtained. Finally, the current calibration page is closed, the corresponding calibration page is opened according to the current page, and the calibration parameters and calibration coefficients are displayed.

[0140] (3) The process of clicking the "next page" button is similar to that of clicking the "previous page" button, except that it is necessary to judge whether it is the last page when the "next page" button is clicked. If it is the last page, the user is prompted that it is the last page, otherwise the page switching process is executed.

[0141] (4) If the "add page" button is clicked, it is first determined whether the current page is the maximum page set by the system. If so, the user is prompted that the maximum page has been reached and the page cannot be added. Otherwise, it is determined whether the current page is equal to the total number of pages. If so, the calibration page adding process is executed. Otherwise, the user is prompted to first turn to the last page and then add the page. The calibration page adding process first determines whether the current page has calibration parameters and calibration coefficient modifications. If so, the user's operation is saved. Then, the current page storage variable is incremented by one and the total number of pages is updated. The calibration reference size values are calculated according to the current page. In the calibration interface, the next page calibration reference value termination data input and the calibration item number input can be performed. The distance value between each calibration item size reference value is (calibration reference value termination data - current page calibration termination data) / calibration item number. According to the distance value, the next page calibration size reference value is calculated. The current calibration page is closed. The corresponding calibration page is opened according to the current page and the calibration size value is displayed.

[0142] (5) If the "delete page" button is clicked, it is first determined whether the current page is equal to the total number of pages. If so, it is further determined whether the current page is the first page. If so, the user is prompted that there is only one page and the page cannot be deleted. Otherwise, the calibration page deleting process is executed. The calibration page deleting process first determines whether the current page has calibration parameters and calibration coefficient modifications. If so, the user's operation is saved. Then, the current page storage variable is decremented by one and the total number of pages is updated. The current page calibration parameters and calibration coefficients are obtained according to the current page storage variable. Finally, the current calibration interface is closed. The corresponding calibration page is opened according to the current page and the calibration parameters and calibration coefficients are displayed.

[0143] (6) By clicking the "exit" button in each calibration page, the differential pressure-dimension value conversion coefficient acquisition interface can be exited, at which time the calibration interface exit process will be executed. This process will first perform the pre-calibration page calibration parameter and calibration coefficient saving operation, and then judge the parameter correlation of each calibration page. The calibration fitting curve of each page must ensure the continuity of the differential pressure, and the calibration dimension value of each page cannot jump, so as to realize the correctness of the differential pressure and dimension conversion. If the differential pressure in the fitting curve is discontinuous, the conversion in the disconnected area cannot be realized. If the calibration dimension value jumps, the dimension may jump in the actual conversion near the same differential pressure. In order to ensure that the calibration curve of each page does not jump on the size axis, the starting size value of each page and the ending size value of the previous page and the ending size value of each page and the starting size value of the next page must be within a certain interval, which can be set in each calibration page. When exiting the page, the starting size value and the ending size value of all pages are judged. If the setting is greater than the interval value, the user is prompted that there is an error setting page. In order to ensure the continuity of the calibration curve of each page on the differential pressure axis, it is necessary to ensure that the starting differential pressure value of each page is equal to the ending differential pressure value of the previous page, and the ending differential pressure value of each page is equal to the starting differential pressure value of the next page. If they are different, the user is prompted that there is an error setting page. If the above size value and differential pressure value meet the requirements, the differential pressure-dimension conversion coefficient acquisition interface is exited, and the measurement calibration conversion interface is returned. The conversion calibration interface is shown in Figure 9

[0144] In the present application, since the workpiece has the thermal expansion and cold contraction phenomenon, it is necessary to perform temperature compensation on the workpiece size. The workpiece performs a temperature-dimension value compensation process to compensate the real-time size after the differential pressure-dimension conversion. The specific steps include:

[0145] It is judged whether the temperature is within the temperature range set in the temperature-dimension value compensation calibration process. If yes, the temperature-dimension value compensation polynomial coefficient is called to perform polynomial calculation to obtain the calibrated size value after temperature compensation. The calculation method of the polynomial is the same as the above-mentioned differential pressure-dimension polynomial calculation method. If the temperature exceeds the set range and the number of threshold values is greater than the set value, an alarm is given.

[0146] In the present application, the temperature and size value compensation coefficient acquisition algorithm is used to compensate the real-time size in the measurement process. The specific steps include:

[0147] The size values of the workpiece at different temperatures are collected, and the least square method is used to fit the obtained multiple groups of data to obtain a one-dimensional polynomial function of temperature relative to size value.

[0148] ​When the system of the gas-electricity meter is started, the hardware initialization process is executed, after the hardware initialization is completed, the self-check of the peripheral device is performed, that is, the self-check of the communication state. When the gas pressure detection and the temperature and humidity detection are performed, if the detection parameter exceeds the set threshold value, the detection value is displayed on the touch screen and the user is prompted to check the gas source pressure and the device environment. The data initialization process reads each detection parameter from the power-off storage module and stores it into the related variable.

[0149] The specific detection parameters include:

[0150] 1. gas source pressure (humidity) - differential pressure compensation calibration coefficient;

[0151] 2. differential pressure - multi-channel coefficient of size value conversion;

[0152] 3. temperature - size value compensation calibration coefficient;

[0153] 4. measurement setting parameter, mainly the reference value, pre-warning value and alarm value parameter of each channel of the workpiece;

[0154] 5. user-selected measurement program number.

[0155] Among the above parameters, the compensation coefficient acquisition algorithm of the gas source pressure (humidity) - differential pressure is applicable to the differential pressure compensation in the size measurement process of all workpieces; the differential pressure - size value conversion, the temperature - size value compensation coefficient acquisition and the measurement setting parameter need to be set differently for different workpieces, therefore, different parameters are stored for each workpiece, and the selection can be switched through the measurement program interface.

[0156] After the hardware initialization is completed, the test program is set, that is, the measurement related parameters are set.

[0157] Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the protection scope of the present application.

Claims

1. A gas and electricity meter based on a parametric compensation calibration multi-channel high speed measurement method, the gas and electricity meter comprising: The acquisition module, the signal processing module and the control module are characterized in that the parameter compensation-based multi-channel high-speed measurement method specifically comprises the following steps: Acquiring the temperature and humidity, the gas source pressure and the pressure difference signal of the measuring head of the workpiece through multiple acquisition channels; processing the acquired signals; Based on the acquired signals, the pressure difference signal is calibrated through a gas source pressure and pressure difference compensation algorithm; Based on the compensated pressure difference signal, the pressure difference signal is converted into corresponding workpiece dimensions through a pressure difference dimension page conversion algorithm; Based on the converted dimension data, a temperature and dimension compensation algorithm is used to calibrate the dimension data at different temperatures; The specific steps of the pressure difference dimension page conversion algorithm for pressure difference dimension conversion include: Page the pressure difference value, place the standard part in the specified position, obtain the corresponding pressure difference value, based on the current pressure difference value, turn the current pressure difference page to the corresponding page, and fill the current pressure difference value into the corresponding value item; if the pressure difference values between pages are equal at both ends, the next step is performed; The pressure difference and the dimension are converted using a multi-order polynomial, and the formula is: wherein SV i is the real-time size after corresponding page conversion, 、 、 、 、 、 、 is the polynomial fitting coefficient of the corresponding page, obtained by the corresponding differential pressure size conversion coefficient obtaining algorithm, and DP is the real-time differential pressure after compensation by the gas source gas pressure.

2. The electro-pneumatic quantity meter based on the parameter compensation calibration multi-channel high-speed measurement method according to claim 1, characterized in that, The steps of the gas source pressure and pressure difference compensation algorithm include: Calculate the gas source pressure and pressure difference compensation value: use the gas source pressure and humidity as parameters for pressure difference compensation, and the relationship between the gas source pressure, humidity and pressure difference is: △DP=f(Gsp,H) Where Gsp is the gas source pressure, △DP is the pressure difference compensation value, H is the current humidity, Gsp and △DP are in a polynomial relationship, H and △DP-Gsp curve are in an interval relationship, and f is a polynomial function of the gas source pressure Gsp and the pressure difference compensation value △DP in a specified temperature interval; Determine the current humidity: if the current humidity exceeds the set humidity, prompt that the humidity is too large and needs to be confirmed; if the current humidity is less than the set humidity, determine the interval of the current humidity corresponding to the △DP-Gsp compensation curve, call the fitting coefficient of the corresponding interval of the △DP-Gsp compensation curve to compensate the pressure difference with the gas source pressure, and the calculation formula is: Wherein, the gas source gas pressure Gsp adopts a multi-order polynomial fitting curve to compensate the differential pressure compensation value ΔDP, is a multi-order polynomial compensation coefficient, which is obtained by a corresponding compensation coefficient acquisition algorithm; Compensate the current real-time pressure difference with the pressure difference compensation value to obtain the compensated real-time pressure difference, and the formula is: DP = DP + ΔDP c DP = DP + ΔDP 3. The electro-pneumatic quantity meter based on the parameter compensation calibration multi-channel high-speed measurement method according to claim 2, characterized in that, The specific steps of the gas source pressure and pressure difference compensation coefficient acquisition algorithm include: Obtain the current environmental real-time humidity at regular intervals; Determine whether the current environmental humidity is within the selected humidity interval, if yes, proceed to the next step, otherwise prompt the user to adjust the environmental humidity or modify the humidity interval; If the current humidity meets the requirements, prompt the user to place the standard part, input the standard part dimension value and the measuring head model, and obtain the calibration data bound with the standard part dimension and the measuring head model; Divide multiple verification intervals according to the set standard gas source pressure, obtain the gas source pressure value and the pressure difference value in all verification intervals, adjust the gas source pressure to the standard pressure, acquire the gas source pressure and pressure difference compensation calibration coefficient for the current humidity, use a one-dimensional polynomial fitting method for compensation calibration, obtain the fitting coefficient through the least square method, and the pressure difference and the gas source pressure are in a one-dimensional six-order polynomial function relationship. If the humidity interval is switched and the calibration coefficient is refitted before the switch, the current humidity interval calibration fitting coefficient is saved, the fitting coefficient save dialog box is popped up, and the fitting coefficient before the humidity interval is switched is selected to be saved; After the fitting coefficient is saved, the user is prompted to adjust the calibration environment humidity, and the current environment humidity is adjusted to the set humidity interval; the above steps are repeated to obtain the gas source pressure and pressure difference compensation calibration coefficient corresponding to the set humidity interval.

4. The electro-pneumatic quantity meter based on the parameter compensation calibration multi-channel high-speed measurement method according to claim 1, characterized in that, The steps of the differential pressure size conversion coefficient acquisition algorithm include: The real-time differential pressure value and the input differential pressure value are obtained, and it is judged whether the current differential pressure indication value is within the set range. If yes, the current differential pressure indication value is filled in the differential pressure value of the corresponding calibration item; According to the start item and the stop item size value and the total number of calibration items, the size value of the differential pressure is divided to obtain all calibration size reference values of the current page and correct the reference values; The corresponding calibration item size value is selected, and the user places the corresponding standard part according to the selected calibration item size value, and fills in the actual size value in the interface which is less than the size value of the previous calibration item and greater than the size value of the next calibration item; If all the standard part size values and the corresponding differential pressure values of the current page meet the requirements, calibration is started. If there are modification items in the differential pressure and size input values, the modification item data is saved, the size value is calculated through a multi-order polynomial function, the least square method is used to fit the size values and the corresponding differential pressure values of all groups of the current page, the coefficients corresponding to the corresponding multi-order polynomial function are obtained, and the calibration coefficients are displayed in the interface; The page conversion operation is performed in the differential pressure size conversion coefficient acquisition interface, and the conversion page operation includes: page adding, page deleting, page turning up, and page turning down operations.

5. The electro-pneumatic quantity meter based on the parameter compensation calibration multi-channel high-speed measurement method according to claim 1, characterized in that, The steps of the temperature and size compensation algorithm include: It is judged whether the current temperature is within the temperature range set in the temperature and size value compensation coefficient acquisition algorithm. If yes, the temperature and size value compensation coefficient acquisition algorithm is called for polynomial calculation to obtain the calibration size value after temperature compensation; If the current temperature exceeds the set range and the number of times of exceeding the threshold value is greater than the set value, an alarm prompt is given.

6. The electro-pneumatic quantity meter based on the parameter compensation calibration multi-channel high-speed measurement method according to claim 5, characterized in that, The specific calculation steps of the temperature and size value compensation coefficient acquisition algorithm are: The workpiece size values at different temperatures are obtained, and the least square method is used to fit the obtained multiple groups of data to obtain a one-variable polynomial function of temperature relative to size value.

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