Steel slag content measuring method based on phase change detection technology

Abstract

The invention discloses a steel slag content measuring method based on a phase change detection technology, and relates to the technical field of ferrous metallurgy, the method comprises the following steps: constructing an electromagnetic detection device consisting of a coil sensor, a pulse excitation generator, a phase detector and a computer, and installing the electromagnetic detection device at a steel ladle tapping hole; a pulse excitation generator is controlled by a computer to generate pulse waves with fixed frequency, the pulse waves are amplified and then act on a coil sensor, an alternating electromagnetic field is generated, and then alternating eddy current is generated in molten steel; a phase detector is used for detecting phase change caused when steel slag in molten steel flows through the coil sensor, and a detected signal is preprocessed and sent to a computer to be processed; and the computer receives and analyzes the signal transmitted by the phase detector, extracts the phase change quantity from the signal, calculates the steel slag content in the molten steel, sets a steel slag content alarm threshold value, and sends an alarm signal and triggers corresponding operation when the steel slag content exceeds the threshold value.

Description

Technical Field

[0001] The invention relates to the technical field of iron and steel metallurgy, and in particular to a method for measuring steel slag content based on phase change detection technology. Background Art

[0002] In the field of iron and steel metallurgy, the slag content in molten steel during the steelmaking and continuous casting process is a crucial parameter. Real-time and accurate control of the slag content in molten steel is of great significance for improving molten steel quality, optimizing steelmaking processes, and reducing waste in production. During the steelmaking and continuous casting process, molten steel often carries a certain amount of slag when it flows out of the ladle. If the slag is not detected and removed in time, it will enter the next process with the molten steel, causing adverse effects on the purity and quality of the molten steel.

[0003] However, traditional methods for detecting slag content mostly rely on manual observation, which is not only inefficient but also easily affected by human factors, resulting in unstable and inaccurate test results. In addition, with the continuous development of iron and steel metallurgical technology, the requirements for molten steel quality are becoming higher and higher. Traditional detection methods can no longer meet the needs of modern steelmaking processes for precise control of slag content. Summary of the invention

[0004] The purpose of the present invention is to provide a method for measuring the content of steel slag based on phase change detection technology to solve the problems raised in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for measuring slag content based on phase change detection technology, the method comprising:

[0006] Step S100: construct an electromagnetic detection device and install it at the ladle outlet, the device consists of a coil sensor, a pulse excitation generator, a phase detector and a computer;

[0007] Step S200: Controlling a pulse excitation generator through a computer to generate a pulse wave of a fixed frequency, amplifying the pulse wave and applying it to an electromagnetic coil sensor to generate an alternating electromagnetic field, and the alternating electromagnetic field further acts on the molten steel to generate an alternating eddy current;

[0008] Step S300: Detecting the phase change caused by the slag in the molten steel flowing through the coil sensor through a phase detector, and pre-processing the detected signal and sending it to a computer for processing;

[0009] Step S400: The computer receives and analyzes the signal transmitted by the phase detector, extracts the phase change amount and calculates the slag content in the molten steel, and sets the slag content alarm threshold. When the slag content exceeds the threshold, an alarm signal is issued and the corresponding operation is triggered.

[0010] Furthermore, the coil sensor in step S100 has a dual-winding structure, including an excitation winding and a detection winding, both of which are composed of n coils; the coil sensor is installed at the ladle outlet, and the molten steel passes through the coils in the excitation winding and the detection winding when flowing out of the ladle.

[0011] In the above technical solution, by installing an electromagnetic detection device at the ladle outlet, the molten steel can be directly monitored in real time, and the changes in the slag content can be reflected in time, ensuring the automation and intelligence of the entire measurement process, reducing manual intervention, and improving the accuracy and reliability of the measurement.

[0012] Furthermore, in step S200, after the computer controls the pulse excitation generator to generate a pulse waveform with a fixed frequency, the pulse waveform is processed by an amplification circuit to generate a pulse signal; the pulse signal acts on the excitation winding of the coil sensor, generating an alternating electromagnetic field of a corresponding frequency around the coil sensor, and when the molten steel flows through the coil sensor, the alternating electromagnetic field generates an alternating eddy current in the molten steel.

[0013] Furthermore, in step S300, when molten steel containing slag flows through the coil sensor, the conductivity difference between the slag and the molten steel causes the phase of the electromagnetic field around the coil sensor to change. At this time, the detection winding senses the change in the electromagnetic field and generates a corresponding electrical signal to transmit to the phase detector; the phase detector receives the electrical signal from the detection winding and performs preprocessing operations on the electrical signal, including anti-interference filtering, signal amplification, and digitization of the electrical signal through an A / D converter, and finally inputs the preprocessed digital signal into a computer.

[0014] In the above technical scheme, the alternating electromagnetic field is generated by controlling the pulse excitation generator, which provides the necessary physical conditions for the subsequent eddy current effect excitation and phase change detection. The phase change is detected by the phase detector, and the signal-to-noise ratio of the data is improved by preprocessing the signal, which ensures the authenticity and validity of the data and provides a basis for subsequent data analysis.

[0015] Furthermore, the step S400 includes the following steps:

[0016] Step S401: Calculate the phase change between the original pulse signal generated by the excitation winding and the electrical signal affected by the electromagnetic field change in represents the phase of the original pulse signal, Indicates the phase of the electrical signal in the detection winding;

[0017] Step S402: define a standard characteristic function f(t) to represent the change of the electromagnetic field with time t when there is no slag content:

[0018]

[0019] Where A represents the amplitude and ω represents the angular frequency;

[0020] Step S403: A phase signal variation function g(t) is defined by the electrical signal of the detection winding received by the phase detector, which represents the variation of the electromagnetic field with time t after the slag content changes:

[0021]

[0022] Where B represents the amplitude that changes due to the slag content.

[0023] Step S404: Analyze the interaction between the excitation signal and the detection signal through convolution operation, take the standard characteristic function f(t) as the convolution kernel, and the phase signal change function g(t) as the input signal, perform convolution operation on the convolution kernel and the input signal, and obtain a result function represented as:

[0024]

[0025] in represents the convolution operation, h(t) is the result function, and represents the influence of slag content on the electromagnetic field distribution.

[0026] Step S405: extract phase features from the feature map obtained by the convolution operation and construct a feature function, extract phase features by calculating the phase angle of each element in the feature map to form a feature vector b; construct an SVM regression model, and use the feature vector b and the corresponding slag content y as a data set to train the model. During the training process, the root mean square error is used as a loss function, and the mapping relationship between the phase feature vector b and the slag content y is obtained by continuously iterating on the training data and minimizing the root mean square error; finally, the trained SVM regression model can obtain the slag content in the molten steel according to the change of the phase feature vector b.

[0027] Step S406: Receive the electrical signal from the detection winding in real time through the phase detector, extract the corresponding phase feature, and input it into the trained model to obtain the slag content in the molten steel; set the slag content alarm threshold. When the calculated slag content exceeds the threshold, the electromagnetic detection device sends an alarm signal and closes the valve to stop steel tapping.

[0028] In the above technical scheme, by calculating the phase change between the original pulse signal generated by the excitation winding and the electrical signal affected by the change of the electromagnetic field, the phase characteristics reflecting the slag content can be extracted; then, the SVM regression model is used to construct a mapping relationship between the phase characteristic vector and the slag content to achieve accurate measurement of the slag content; in addition, by setting the slag content alarm threshold, an alarm signal is issued when the measured value exceeds the threshold, which helps to take timely measures to avoid production accidents and quality problems.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The present invention reflects the change of slag content by measuring the change of electromagnetic field phase, and has higher measurement accuracy than traditional chemical analysis methods or physical testing methods; the phase detector can receive and process the electrical signal from the detection winding in real time, extract the phase characteristics, and thus more accurately reflect the actual situation of the slag content. Compared with traditional manual sampling and detection methods, the present invention reduces the possibility of manual intervention and human errors.

[0031] The present invention can monitor the slag content in molten steel in real time, and send out an alarm signal when the content exceeds a set threshold, and close the valve in time to stop steel tapping, thereby effectively avoiding the negative impact of slag on the production process. This helps steel companies to realize automation and intelligence of the production process and improve production efficiency and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A method flow chart of a method for measuring slag content based on phase change detection technology of the present invention;

[0033] Figure 2 This is a diagram of the steel slag content calculation process of a steel slag content measurement method based on phase change detection technology of the present invention. DETAILED DESCRIPTION

[0034] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0035] Example: Figure 1-Figure 2 As shown, the present invention provides a method for measuring slag content based on phase change detection technology, the method comprising:

[0036] Step S100: construct an electromagnetic detection device and install it at the ladle outlet, the device consists of a coil sensor, a pulse excitation generator, a phase detector and a computer;

[0037] Step S200: Controlling a pulse excitation generator through a computer to generate a pulse wave of a fixed frequency, amplifying the pulse wave and applying it to an electromagnetic coil sensor to generate an alternating electromagnetic field, and the alternating electromagnetic field further acts on the molten steel to generate an alternating eddy current;

[0038] Step S300: Detecting the phase change caused by the slag in the molten steel flowing through the coil sensor through a phase detector, and pre-processing the detected signal and sending it to a computer for processing;

[0039] Step S400: The computer receives and analyzes the signal transmitted by the phase detector, extracts the phase change amount and calculates the slag content in the molten steel, and sets the slag content alarm threshold. When the slag content exceeds the threshold, an alarm signal is issued and the corresponding operation is triggered.

[0040] The coil sensor in step S100 has a double-winding structure, including an excitation winding and a detection winding, both of which are composed of n coils; the coil sensor is installed at the ladle outlet, and the molten steel passes through the coils in the excitation winding and the detection winding when flowing out of the ladle.

[0041] In the above technical solution, by installing an electromagnetic detection device at the ladle outlet, the molten steel can be directly monitored in real time, and the changes in the slag content can be reflected in time, ensuring the automation and intelligence of the entire measurement process, reducing manual intervention, and improving the accuracy and reliability of the measurement.

[0042] In step S200, after the computer controls the pulse excitation generator to generate a pulse waveform with a fixed frequency, the pulse waveform is processed by the amplification circuit to generate a pulse signal; the pulse signal acts on the excitation winding of the coil sensor, generating an alternating electromagnetic field of a corresponding frequency around the coil sensor, and when the molten steel flows through the coil sensor, the alternating electromagnetic field generates an alternating eddy current in the molten steel.

[0043] In step S300, when molten steel containing slag flows through the coil sensor, the conductivity difference between the slag and the molten steel causes the phase of the electromagnetic field around the coil sensor to change. At this time, the detection winding senses the change in the electromagnetic field and generates a corresponding electrical signal to transmit to the phase detector; the phase detector receives the electrical signal from the detection winding and performs preprocessing operations on the electrical signal, including anti-interference filtering, signal amplification, and digitization of the electrical signal through an A / D converter, and finally inputs the preprocessed digital signal into a computer.

[0044] In the above technical scheme, the alternating electromagnetic field is generated by controlling the pulse excitation generator, which provides the necessary physical conditions for the subsequent eddy current effect excitation and phase change detection. The phase change is detected by the phase detector, and the signal-to-noise ratio of the data is improved by preprocessing the signal, which ensures the authenticity and validity of the data and provides a basis for subsequent data analysis.

[0045] The step S400 includes the following steps:

[0046] Step S401: Calculate the phase change between the original pulse signal generated by the excitation winding and the electrical signal affected by the electromagnetic field change in represents the phase of the original pulse signal, Indicates the phase of the electrical signal in the detection winding;

[0047] Step S402: define a standard characteristic function f(t) to represent the change of the electromagnetic field with time t when there is no slag content:

[0048]

[0049] Where A represents the amplitude and ω represents the angular frequency;

[0050] Step S403: A phase signal variation function g(t) is defined by the electrical signal of the detection winding received by the phase detector, which represents the variation of the electromagnetic field with time t after the slag content changes:

[0051]

[0052] Where B represents the amplitude that changes due to the slag content.

[0053] Step S404: Analyze the interaction between the excitation signal and the detection signal through convolution operation, take the standard characteristic function f(t) as the convolution kernel, and the phase signal change function g(t) as the input signal, perform convolution operation on the convolution kernel and the input signal, and obtain a result function represented as:

[0054]

[0055] in represents the convolution operation, h(t) is the result function, and represents the influence of slag content on the electromagnetic field distribution.

[0056] Step S405: extract phase features from the feature map obtained by the convolution operation and construct a feature function, extract phase features by calculating the phase angle of each element in the feature map to form a feature vector b; construct an SVM regression model, and use the feature vector b and the corresponding slag content y as a data set to train the model. During the training process, the root mean square error is used as a loss function, and the mapping relationship between the phase feature vector b and the slag content y is obtained by continuously iterating on the training data and minimizing the root mean square error; finally, the trained SVM regression model can obtain the slag content in the molten steel according to the change of the phase feature vector b.

[0057] Step S406: Receive the electrical signal from the detection winding in real time through the phase detector, extract the corresponding phase feature, and input it into the trained model to obtain the slag content in the molten steel; set the slag content alarm threshold. When the calculated slag content exceeds the threshold, the electromagnetic detection device sends an alarm signal and closes the valve to stop steel tapping.

[0058] In the above technical scheme, by calculating the phase change between the original pulse signal generated by the excitation winding and the electrical signal affected by the change of the electromagnetic field, the phase characteristics reflecting the slag content can be extracted; then, the SVM regression model is used to construct a mapping relationship between the phase characteristic vector and the slag content to achieve accurate measurement of the slag content; in addition, by setting the slag content alarm threshold, an alarm signal is issued when the measured value exceeds the threshold, which helps to take timely measures to avoid production accidents and quality problems.

[0059] The embodiment of the present invention is as follows: an electromagnetic detection device is constructed and installed at the ladle outlet, the device is composed of a coil sensor, a pulse excitation generator, a phase detector and a computer; wherein the coil sensor uses a double winding structure, including an excitation winding and a detection winding, the excitation winding is fired by 10 turns of copper wire, the coil diameter is 50mm, the excitation frequency is 100kHz, and it serves as the transmission part of the pulse signal; the detection winding is fired by 10 turns of copper wire, the coil diameter is 50mm, it senses the change of the surrounding magnetic field, and outputs an electrical signal to the phase detector; the pulse excitation generator generates a pulse wave with a fixed frequency, and the pulse width is set to 1μs;

[0060] The fixed frequency pulse wave generated by the pulse excitation generator is 100kHz. The pulse signal is amplified 10 times by the amplifier. The output signal acts on the excitation winding to generate an alternating electromagnetic field with a frequency of 100kHz. The alternating electromagnetic field forms eddy currents in the molten steel. Due to its low electrical conductivity, the steel slag will interfere with the distribution of the eddy currents, thereby causing a change in the phase of the electromagnetic field. When the steel slag flows through the sensor, the electromagnetic field will change in phase due to the difference in electrical conductivity between the steel slag and the molten steel. These phase changes are sensed by the detection winding and converted into electrical signals. A bandpass filter (frequency of 90kHz) is used to remove high-frequency noise, retain the signal within the target frequency range, and amplify it 20 times through an amplifier circuit to make the signal meet the input requirements of the phase detector. The analog signal is converted into a digital signal through an A / D converter and input into a computer for further processing.

[0061] Calculate the phase change between the original pulse signal generated by the exciting winding and the electrical signal affected by the electromagnetic field change The phase of the original pulse signal Detecting the phase of the electrical signal in the winding Where A = 1, ω represents the angular frequency (ω = 2πf, f = 100kHz);

[0062] The standard characteristic function f(t) represents the variation of the electromagnetic field with time t when there is no slag content:

[0063]

[0064] Where A represents the amplitude and ω represents the angular frequency;

[0065] The electrical signal of the detection winding received by the phase detector defines a phase signal change function g(t), which represents the change of the electromagnetic field with time t after the slag content changes:

[0066]

[0067] Where B represents the amplitude affected by the slag content, B = 0.9;

[0068] The interaction between the excitation signal and the detection signal is analyzed by convolution operation. The standard characteristic function f(t) is used as the convolution kernel, the phase signal change function g(t) is used as the input signal, and the convolution kernel is convolved with the input signal to obtain a result function represented as:

[0069]

[0070] in represents the convolution operation, h(t) is the result function, and represents the influence of slag content on the electromagnetic field distribution.

[0071] Phase features are extracted from the feature map obtained by convolution operation and a feature function is constructed. The phase features are extracted by calculating the phase angle of each element in the feature map to form a feature vector b. A SVM regression model is constructed, and the feature vector b and the corresponding slag content y constitute a data set training model. There are a total of 100 groups of data, each of which includes a feature vector b and a slag content y. During the training process, the root mean square error is used as the loss function. The mapping relationship between the phase feature vector b and the slag content y is obtained by continuously iterating on the training data and minimizing the root mean square error. Finally, the trained SVM regression model can obtain the slag content in the molten steel according to the change of the phase feature vector b.

[0072] The phase detector receives the electrical signal from the detection winding in real time, extracts the corresponding phase features, and inputs them into the trained model to obtain the slag content in the molten steel; the slag content alarm threshold is set to 5%; when the calculated slag content exceeds 5%, the electromagnetic detection device sends an alarm signal and closes the valve to stop steel tapping.

[0073] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for measuring slag content based on phase change detection technology, characterized in that: The method comprises: Step S100: construct an electromagnetic detection device and install it at the ladle outlet, the device consists of a coil sensor, a pulse excitation generator, a phase detector and a computer; Step S200: Controlling a pulse excitation generator through a computer to generate a pulse wave of a fixed frequency, amplifying the pulse wave and applying it to an electromagnetic coil sensor to generate an alternating electromagnetic field, and the alternating electromagnetic field further acts on the molten steel to generate an alternating eddy current; Step S300: Detecting the phase change caused by the slag in the molten steel flowing through the coil sensor through a phase detector, and pre-processing the detected signal and sending it to a computer for processing; Step S400: The computer receives and analyzes the signal transmitted by the phase detector, extracts the phase change amount and calculates the slag content in the molten steel, and sets the slag content alarm threshold. When the slag content exceeds the threshold, an alarm signal is issued and the corresponding operation is triggered.

2. The method for measuring slag content based on phase change detection technology according to claim 1, characterized in that: The coil sensor in step S100 has a double-winding structure, including an excitation winding and a detection winding, both of which are composed of n coils; the coil sensor is installed at the ladle outlet, and the molten steel passes through the coils in the excitation winding and the detection winding when flowing out of the ladle.

3. The method for measuring slag content based on phase change detection technology according to claim 1 is characterized in that: In step S200, after the computer controls the pulse excitation generator to generate a pulse waveform with a fixed frequency, the pulse waveform is processed by the amplification circuit to generate a pulse signal; the pulse signal acts on the excitation winding of the coil sensor, generating an alternating electromagnetic field of a corresponding frequency around the coil sensor, and when the molten steel flows through the coil sensor, the alternating electromagnetic field generates an alternating eddy current in the molten steel.

4. The method for measuring slag content based on phase change detection technology according to claim 1 is characterized in that: In step S300, when molten steel containing slag flows through the coil sensor, the conductivity difference between the slag and the molten steel causes the phase of the electromagnetic field around the coil sensor to change. At this time, the detection winding senses the change in the electromagnetic field and generates a corresponding electrical signal to transmit to the phase detector; the phase detector receives the electrical signal from the detection winding and performs preprocessing operations on the electrical signal, including anti-interference filtering, signal amplification, and digitization of the electrical signal through an A / D converter, and finally inputs the preprocessed digital signal into a computer.

5. The method for measuring slag content based on phase change detection technology according to claim 1, characterized in that: The step S400 includes the following steps: Step S401: Calculate the phase change between the original pulse signal generated by the excitation winding and the electrical signal affected by the electromagnetic field change in represents the phase of the original pulse signal, Indicates the phase of the electrical signal in the detection winding; Step S402: define a standard characteristic function f(t) to represent the change of the electromagnetic field with time t when there is no slag content: Where A represents the amplitude and ω represents the angular frequency; Step S403: A phase signal variation function g(t) is defined by the electrical signal of the detection winding received by the phase detector, which represents the variation of the electromagnetic field with time t after the slag content changes: Where B represents the amplitude that changes due to the slag content.

6. The method for measuring slag content based on phase change detection technology according to claim 1 is characterized in that: The step S400 further includes: Step S404: Analyze the interaction between the excitation signal and the detection signal through convolution operation, take the standard characteristic function f(t) as the convolution kernel, and the phase signal change function g(t) as the input signal, perform convolution operation on the convolution kernel and the input signal, and obtain a result function represented as: in represents the convolution operation, h(t) is the result function, and represents the influence of slag content on the electromagnetic field distribution.

7. The method for measuring slag content based on phase change detection technology according to claim 1 is characterized in that: The step S400 further includes: Step S405: extract phase features from the feature map obtained by the convolution operation and construct a feature function, extract phase features by calculating the phase angle of each element in the feature map to form a feature vector b; construct an SVM regression model, and use the feature vector b and the corresponding slag content y as a data set to train the model. During the training process, the root mean square error is used as a loss function, and the mapping relationship between the phase feature vector b and the slag content y is obtained by continuously iterating on the training data and minimizing the root mean square error; finally, the trained SVM regression model can obtain the slag content in the molten steel according to the change of the phase feature vector b.

8. The method for measuring slag content based on phase change detection technology according to claim 1 is characterized in that: The step S400 further includes: Step S406: Receive the electrical signal from the detection winding in real time through the phase detector, extract the corresponding phase feature, and input it into the trained model to obtain the slag content in the molten steel; set the slag content alarm threshold. When the calculated slag content exceeds the threshold, the electromagnetic detection device sends an alarm signal and closes the valve to stop steel tapping.

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