阅读说明：本技术 一种用于连铸结晶器专家系统的主动抗电磁搅拌干扰装置 (Active anti-electromagnetic stirring interference device for continuous casting crystallizer expert system ) 是由 方志宏 夏勇 吴存有 吴建明 陆敏健 于 2018-06-25 设计创作，主要内容包括：本发明公开一种用于连铸结晶器专家系统的主动抗电磁搅拌干扰装置,包括：电磁搅拌电源、温度信号采集单元、专家系统计算单元、输出电流检测模块以及抗干扰模块,其中,抗干扰模块包括多个温度放大器、多个增益调整电路、多个相位调整电路、多个减法电路、以及幅值零位恢复电路。相位调整电路对干扰抵消信号的相位进行调整使之与温度传感器干扰信号相同。幅值零位恢复电路使实际干扰信号的幅值为零。本发明装置可以完全消除电磁搅拌对结晶器专家系统的干扰,最终使电磁搅拌系统能够正常投运。通过把握干扰特性,传输方式,对周边设备的干扰机理,将其对漏钢预报干扰从原理上完全消除。(The invention discloses an active anti-electromagnetic stirring interference device for a continuous casting crystallizer expert system, which comprises: the electromagnetic stirring power supply, the temperature signal acquisition unit, expert system computational element, output current detection module and anti-interference module, wherein, anti-interference module includes a plurality of temperature amplifiers, a plurality of gain adjustment circuit, a plurality of phase adjustment circuit, a plurality of subtraction circuit and amplitude zero restoration circuit. The phase adjustment circuit adjusts the phase of the interference cancellation signal to be the same as the temperature sensor interference signal. The amplitude zero restoration circuit makes the amplitude of the actual interference signal zero. The device can completely eliminate the interference of electromagnetic stirring on the expert system of the crystallizer, and finally the electromagnetic stirring system can be normally put into operation. By grasping the interference characteristics, the transmission mode and the interference mechanism on peripheral equipment, the interference on breakout prediction is completely eliminated in principle.)

1. An active anti-electromagnetic stirring interference device for a continuous casting crystallizer expert system, comprising: electromagnetic stirring power, temperature signal acquisition unit and expert system computational unit, its characterized in that, the device still includes: output current detection module and anti-interference module, wherein:

the temperature signal acquisition unit comprises a plurality of temperature sensors 1-N;

the output current detection module comprises a plurality of electromagnetic stirring current detectors 1-N;

the anti-interference module comprises a plurality of temperature amplifiers 1-N, a plurality of gain adjusting circuits 1-N, a plurality of phase adjusting circuits 1-N, a plurality of subtraction circuits 1-N and an amplitude zero restoration circuit 1-N, wherein:

a temperature signal of one of the plurality of temperature sensors 1 to N is supplied to a corresponding one of the plurality of temperature amplifiers 1 to N, and the amplified signal is input to a corresponding one of the plurality of subtraction circuits 1 to N;

a current signal of one of the plurality of electromagnetic stirring current detectors 1 to N is supplied to a corresponding one of the plurality of gain adjusting circuits 1 to N, a gain-adjusted signal is input to a corresponding one of the plurality of phase adjusting circuits 1 to N, and a phase-adjusted signal is input to a corresponding one of the plurality of subtracting circuits 1 to N;

the subtracting circuit subtracts the two input signals to eliminate the interference component in the temperature signal;

and an output signal of the subtraction circuit is input into a corresponding amplitude zero restoration circuit in the amplitude zero restoration circuits 1 to N, the amplitude zero restoration circuit restores the amplitude of the input signal, and the signal after the amplitude restoration is provided to the temperature detection unit of the crystallizer expert system.

2. The active electromagnetic stirring disturbance resistance device for a continuous casting crystallizer expert system as set forth in claim 1, characterized in that:

when electromagnetic stirring is not applied, the amplitude zero-position recovery circuit adjusts the temperature signal, so that the amplitude and the zero position of the output temperature signal are the same as those of the input temperature signal.

3. The active electromagnetic stirring disturbance resistance device for a continuous casting crystallizer expert system as set forth in claim 1, characterized in that:

the temperature sensor generates an interference signal St, the electromagnetic stirring current detector generates an interference cancellation signal Si,

the phase adjustment circuit adjusts the phase θ of the interference cancellation signal output by the gain adjustment circuit, so that the phase of the interference cancellation signal is in phase with the interference signal St of the temperature sensor.

4. The active electromagnetic stirring interference resistance device for a continuous casting crystallizer expert system as set forth in claim 3, characterized in that: after the phase of the interference cancellation signal is adjusted in place, the amplitude zero-position recovery circuit adjusts the amplitude of the interference cancellation signal, so that the amplitude of the actual interference signal Sr in the output temperature signal is zero.

5. The active electromagnetic stirring disturbance resistance device for a continuous casting crystallizer expert system as set forth in claim 1, characterized in that:

the temperature sensors are thermocouple temperature sensor arrays arranged on the periphery of the continuous casting crystallizer.

6. The active electromagnetic stirring disturbance resistance device for a continuous casting crystallizer expert system as set forth in claim 1, characterized in that: the electromagnetic stirring current detector is an electromagnetic stirring current transformer.

7. The active electromagnetic stirring disturbance resistance device for a continuous casting crystallizer expert system as set forth in claim 1, characterized in that: when the crystallizer is electromagnetically stirred, the working frequency is 4.5Hz, the carrier frequency is 2KHz, the highest harmonic frequency is 350KHz, and the highest working current is 600A.

Technical Field

The invention relates to an electromagnetic stirring device of a continuous casting crystallizer, in particular to an active electromagnetic stirring interference resisting device for an expert system of the continuous casting crystallizer.

Background

Electromagnetic stirring is an important process means for improving the quality of casting blank products, and molten steel in a crystallizer is stirred through a periodic electromagnetic field, so that the surface quality of the casting blank is improved, and defects are reduced. Under the background of continuously increasing product requirements, the technology is more and more widely used. However, when the device works, a strong electromagnetic field is generated around the device to interfere peripheral control equipment, normal production cannot be realized, and stable operation of the production control equipment under the electromagnetic stirring interference condition is ensured by a matched anti-interference means.

The crystallizer expert system is equipment for detecting important process states around the crystallizer and is used for judging whether steel leakage is caused by bonding or not and judging whether heat conduction of the crystallizer is normal or not so as to guarantee smooth production and guarantee quality of casting blanks. The basis is an array of thermocouple temperature sensors arranged on a crystallizer, which usually has 3 rows per side and 6 to 15 thermocouples per row of long sides. The working temperature of each thermocouple is 0-400 ℃, and the total is 0-16 mV. When the electromagnetic stirring device is actually used on site, the working current of the electromagnetic stirring device is 600A, the interference on the expert system of the crystallizer is close to the full range, and the production smoothness is seriously interfered.

The traditional hardware part anti-interference measures include: power supply purification design; suppressing input and output channel interference; the suppression of the electric isolation technology and the back electromotive force interference; the electric shielding technology and the anti-interference design of the transmission line; the existing anti-interference technology is difficult to eliminate the electromagnetic interference generated by the electromagnetic stirring around the crystallizer and the current of 600A.

The following table lists conventional interference rejection measures:

the invention patent application with the application number of 201310138991.5 discloses an electromagnetic inductor of an electromagnetic stirring device of a slab continuous casting crystallizer. The electromagnetic inductor with the magnetic shielding cover structure can change the space trend of magnetic lines of force, generate higher magnetic induction intensity, improve the electromagnetic force, improve the system efficiency and simultaneously reduce the magnetic field of the stirring device to peripheral equipment and meters. Although this technique can be improved due to the structural limitations of the crystallizer, the interference of electromagnetic stirring with the expert system of the crystallizer cannot be completely eliminated.

Therefore, the strong electromagnetic interference of the electromagnetic stirring device to surrounding measurement and control equipment needs to be solved by a technology of reasonably adjusting the amplitude and phase of an output state signal of electromagnetic stirring by a systematized test analysis and an anti-interference device according to the detected signal, so that the interference effect on a crystallizer expert system can be just counteracted, and a breakout prediction system, a liquid level gauge and a crystallizer width adjusting device are eliminated.

Disclosure of Invention

The invention aims to provide an active anti-electromagnetic stirring interference device for a crystallizer expert system and a working process control method. The method establishes systematic and perfect electromagnetic field measurement means, analysis method and development and test technology of anti-interference devices, eliminates anti-electromagnetic interference in production, ensures the smooth production, and provides means for optimization technology of high-power metallurgical equipment. The large-current equipment with the voltage of more than 600A/380V and the precision measurement equipment with the voltage of 16mV can be fused in a system, and the interference of an electromagnetic stirring device on the peripheral key measurement and control equipment of the crystallizer of the continuous casting machine is completely eliminated. The electromagnetic stirring and the crystallizer expert system are prevented from being switched to be used, the electromagnetic stirring is stopped at the moment of measurement, and the measurement is stopped during the electromagnetic stirring. The intermittent operation reduces the process effect of electromagnetic stirring.

In order to achieve the purpose, the invention adopts the following technical scheme:

an active anti-electromagnetic stirring interference device for a continuous casting crystallizer expert system, comprising: electromagnetic stirring power, temperature signal acquisition unit and expert system computational element, the device still includes: output current detection module and anti-interference module, wherein:

the temperature signal acquisition unit comprises a plurality of temperature sensors 1-N;

the output current detection module comprises a plurality of electromagnetic stirring current detectors 1-N;

the anti-interference module comprises a plurality of temperature amplifiers 1-N, a plurality of gain adjusting circuits 1-N, a plurality of phase adjusting circuits 1-N, a plurality of subtraction circuits 1-N and an amplitude zero restoration circuit 1-N, wherein:

a temperature signal of one of the plurality of temperature sensors 1 to N is supplied to a corresponding one of the plurality of temperature amplifiers 1 to N, and the amplified signal is input to a corresponding one of the plurality of subtraction circuits 1 to N;

a current signal of one of the plurality of electromagnetic stirring current detectors 1 to N is supplied to a corresponding one of the plurality of gain adjusting circuits 1 to N, a gain-adjusted signal is input to a corresponding one of the plurality of phase adjusting circuits 1 to N, and a phase-adjusted signal is input to a corresponding one of the plurality of subtracting circuits 1 to N;

the subtracting circuit subtracts the two input signals to eliminate the interference component in the temperature signal;

and an output signal of the subtraction circuit is input into a corresponding amplitude zero restoration circuit in the amplitude zero restoration circuits 1 to N, the amplitude zero restoration circuit restores the amplitude of the input signal, and the signal after the amplitude restoration is provided to the temperature detection unit of the crystallizer expert system.

According to the embodiment of the invention, when no electromagnetic stirring is applied, the amplitude zero restoration circuit adjusts the temperature signal so that the amplitude and the zero of the output temperature signal are the same as the amplitude and the zero of the input temperature signal.

The temperature sensor generates an interference signal St, the electromagnetic stirring current detector generates an interference cancellation signal Si,

the phase adjustment circuit adjusts the phase θ of the interference cancellation signal output by the gain adjustment circuit, so that the phase of the interference cancellation signal is in phase with the interference signal St of the temperature sensor.

After the phase of the interference cancellation signal is adjusted in place, the amplitude zero-position recovery circuit adjusts the amplitude of the interference cancellation signal, so that the amplitude of the actual interference signal Sr in the output temperature signal is zero.

The temperature sensors are thermocouple temperature sensor arrays arranged on the periphery of the continuous casting crystallizer.

The electromagnetic stirring current detector is an electromagnetic stirring current transformer.

When the crystallizer is electromagnetically stirred, the working frequency is 4.5Hz, the carrier frequency is 2KHz, the highest harmonic frequency is 350KHz, and the highest working current is 600A.

The invention can enable heavy current equipment with the voltage of more than 600A/380V and precision measurement equipment with the voltage of 16mV to be mutually fused in a system, and completely eliminates the interference of the electromagnetic stirring device on key measurement and control equipment at the periphery of the crystallizer of the continuous casting machine. The electromagnetic stirring and the crystallizer expert system are prevented from being switched to be used, the electromagnetic stirring is stopped at the moment of measurement, and the measurement is stopped during the electromagnetic stirring. The intermittent operation reduces the process effect of electromagnetic stirring.

Drawings

Other features, objects and advantages of the present invention will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, with reference to the accompanying drawings.

FIG. 1 is a schematic view of the structure of a crystallizer electromagnetic stirrer;

FIG. 2 is a schematic view of the magnetic field around the mold;

FIG. 3 is a layout of an electromagnetic stirrer and crystallizer expert system;

FIG. 4 is a field disturbance scenario;

FIG. 5 is a general structural layout diagram of a tamper-resistant apparatus in accordance with the present invention;

FIG. 6 is a block diagram of the tamper resistant module in the overall configuration of the tamper resistant device;

FIG. 7 is a schematic diagram of phase adjustment during interference signal cancellation;

FIG. 8 is a schematic diagram of amplitude adjustment during interference signal cancellation;

FIG. 9 is a screen shot of a jamming signal feature;

fig. 10 is a diagram of the effect of the crystallizer expert system after being tamper resistant.

Detailed Description

The technical scheme of the invention is specifically explained in the following with the accompanying drawings of the specification.

The detailed features and advantages of the present invention are described in detail in the detailed description which follows, and will be sufficient for anyone skilled in the art to understand the technical content of the present invention and to implement the present invention, and the related objects and advantages of the present invention will be easily understood by those skilled in the art from the description, claims and drawings disclosed in the present specification.

Fig. 1 shows a schematic structural view of a crystallizer electromagnetic stirrer. The electromagnetic stirring device generally uses a five-pole stirrer, the geometric model of which is shown in fig. 1, and thirty groups of coils are arranged on two sides of the crystallizer respectively, and the phase difference between two adjacent groups of coils is 60 degrees.

The distribution of the electromagnetic field at different phase angles in the mould steel on the horizontal plane of the centre plane of the stirrer core is shown in figure 2. The maximum magnetic induction intensity moves to the left side in turn along with the change of the phase angle in the alternating current period of the stirrer winding, and is a typical travelling wave magnetic field.

Obviously, the changing strong magnetic field causes severe interference to the effect measurement and control devices around the crystallizer. In particular the expert system of the crystalliser, is arranged on the copper plate of the crystalliser between the 2 stirring devices. The system comprises a temperature sensor, a temperature signal acquisition module and a model calculation unit. And the calculating unit judges whether the adhesive breakout occurs or not according to the change rule of the temperature. The crystallizer copper plate surface temperature sensor is installed in the copper plate of the crystallizer, each copper plate is provided with 3 heat-extraction couples, the couples are transmitted to a signal measuring device through a group of long compensating wires, and then the signal measuring device collects the sensor signals.

Fig. 3 shows a layout of the electromagnetic stirrer and crystallizer expert system. The electromagnetic stirrer and crystallizer expert system comprises an electromagnetic stirring power supply, a temperature signal acquisition unit and an expert system calculation unit.

Since the distance between the electromagnetic stirring high-power interference source and the temperature signal acquisition device of the crystallizer expert system is too close, the interference signal is too large, so that very strong interference is caused, and the result is shown in fig. 4. In this case, the crystallizer expert system is completely inoperable.

The invention discloses a crystallizer electromagnetic stirring device, which utilizes a current transformer as an interference detection unit of the electromagnetic stirring device, detects the output current of the electromagnetic stirring device as an interference signal of a crystallizer expert system.

Fig. 5 shows an active electromagnetic stirrer interference prevention device of the expert system of the crystallizer according to the invention. Unlike the electromagnetic stirrer and crystallizer expert system shown in fig. 3, the apparatus further comprises an output current detection module and an anti-interference module.

As shown in fig. 5, the anti-jamming module includes a plurality of temperature amplifiers 1 to N, a plurality of gain adjusting circuits 1 to N, a plurality of phase adjusting circuits 1 to N, a plurality of subtracting circuits 1 to N, and an amplitude zero restoration circuit 1 to N, where:

one of the plurality of temperature amplifiers 1 to N receives a temperature signal from a corresponding one of the plurality of temperature sensors 1 to N, and the amplified signal is input to a corresponding one of the plurality of subtraction circuits 1 to N;

one of the plurality of gain adjusting circuits 1 to N receives a current signal from a corresponding one of the plurality of electromagnetic stirring current detectors 1 to N, the gain-adjusted signal is input to a corresponding one of the plurality of phase adjusting circuits 1 to N, and the phase-adjusted signal is input to a corresponding one of the plurality of subtracting circuits 1 to N;

the subtracting circuit subtracts the two input signals to eliminate the interference component in the temperature signal;

and an output signal of the subtraction circuit is input into a corresponding amplitude zero restoration circuit in the amplitude zero restoration circuits 1 to N, the amplitude zero restoration circuit restores the amplitude of the input signal, and the signal after the amplitude restoration is provided to the temperature detection unit of the crystallizer expert system.

Because the electromagnetic stirring interference magnetic field acts on the temperature sensor and the circuit, the generated interference signal is consistent with the frequency and the phase of the electromagnetic stirring output current, and the detected current signal is actively superposed by utilizing the characteristic to eliminate the interference signal.

Fig. 6 shows a schematic block diagram of an interference suppression module in the active electromagnetic stirrer interference suppression device of the crystallizer expert system according to the invention. The crystallizer expert system has N temperature signals, each temperature signal is amplified by a temperature signal amplifying circuit (1-N) and then input into a corresponding subtraction circuit after being amplified; signals detected by the electromagnetic stirring current transformer are used as interference source signals to enter gain adjusting circuits (1-N) and phase adjusting circuits (1-N) for processing, the processed signals are input into corresponding subtraction circuits, the subtraction circuits subtract the signals, interference components in temperature signals are eliminated, and the signals are sent to temperature detecting units (1-N) after amplitude recovery.

Because the installation positions of the temperature sensors of 1-N crystallizer expert systems are different in wiring path, the amplitude and the phase of interference signals acting on the sensors are also greatly different. For this purpose, the amplitude and phase of the interference cancellation signal need to be further adjusted.

1. And adjusting the temperature signal. When no electromagnetic stirring is applied, the amplitude recovery circuit of the temperature signal is adjusted to enable the amplitude and the zero position of the output temperature signal to be the same as those of the input temperature signal. The accuracy of basic temperature signals in the whole anti-interference process is ensured.

2. Phase adjustment of the interference cancellation signal Si. In order to make the interference cancellation signal Si identical to the interference signal St on the temperature sensor, the amplitude and phase of the interference cancellation signal Si need to be adjusted reasonably. First, the phase relation θ is adjusted to minimize the fluctuation amplitude of the interference signal Sr in the output signal, and the phase of the interference cancellation signal at this time is the optimal phase setting signal, that is, θ is equal to 0. As shown in fig. 7 and 8, only when the phase of the interference cancellation signal is optimal, the interference component in the output signal is minimized.

3. The amplitude of the interference cancellation signal Si is adjusted. When the phase θ of the interference cancellation signal Si is adjusted in place, only the amplitude of the interference cancellation signal Si is adjusted. As shown in fig. 8, the amplitude of the actual disturbance signal Sr in the output temperature signal is made zero.

Therefore, each temperature detection channel of the crystallizer expert system can be quickly and accurately adjusted by a simpler method, and the aim of completely eliminating electromagnetic stirring interference is fulfilled.

The patent application of the invention aims at an anti-interference technology matched with an electromagnetic stirring device of a crystallizer, and is an active anti-electromagnetic stirring interference device for an expert system of the crystallizer. When the crystallizer is electromagnetically stirred, the working frequency is 4.5Hz, the carrier frequency is 2KHz, and the highest harmonic frequency can reach 350 KHz. The operating current is up to 600A. Under the condition of the electromagnetic stirring current 100A, the peak value of the amplitude of the interference signal is about 4V, the amplitude is larger, the interference is impulse type interference, at the position of 160KHz, the energy of the interference is largest, the interference is dispersed at each component, and the signal intensity is lower. The frequency characteristics of the disturbance are generally consistent but the amplitude is increased by 6 times with a greater effect than 100A for the 600A condition. The results of the field preliminary test are shown in fig. 9.

The device disclosed by the invention can completely eliminate the interference of electromagnetic stirring on the crystallizer expert system, and finally the electromagnetic stirring system can be normally put into operation. This patent is through holding interference characteristic, transmission mode, to peripheral equipment's interference mechanism. The interference of the leakage steel forecasting device on the leakage steel forecasting is completely eliminated in principle, so that the production is smooth. The electromagnetic stirring device can enable large-current electromagnetic stirring equipment with the current of more than 600A and precise measurement equipment with the current of less than 0.1A to be fused in a production system, avoids the mutual switching use of a plurality of steel manufacturers, stops electromagnetic stirring at the measurement moment, intermittently uses the electromagnetic stirring, and reduces the electromagnetic stirring action capacity.

When the device is used and works in the electromagnetic stirring of the crystallizer, the peripheral precise measurement and control system can be normally operated during continuous casting production. Through the device, the stability of the continuous casting measurement and control equipment can be improved, the precision of the equipment is improved, the lean level of continuous casting production is improved, the smooth production and the product quality are ensured, and cost reduction and efficiency improvement are realized. Fig. 10 shows the effect diagram of the crystallizer expert system after interference rejection.

The invention can enable heavy current equipment with the voltage of more than 600A/380V and precision measurement equipment with the voltage of 16mV to be mutually fused in a system, and completely eliminates the interference of the electromagnetic stirring device on key measurement and control equipment at the periphery of the crystallizer of the continuous casting machine. The electromagnetic stirring and the crystallizer expert system are prevented from being switched to be used, the electromagnetic stirring is stopped at the moment of measurement, and the measurement is stopped during the electromagnetic stirring. The intermittent operation reduces the process effect of electromagnetic stirring.

Finally, it should be noted that while the present invention has been described with reference to the specific embodiments thereof, it should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be construed as limiting the present invention, and various equivalent changes and substitutions may be made therein without departing from the spirit of the present invention, and therefore, it is intended that all changes and modifications to the above embodiments within the spirit and scope of the present invention be covered by the appended claims.