CN117198564B - Electromagnetic injection armature bore-out speed dynamic control method for fracture alleviation - Google Patents

Abstract

The present invention discloses a dynamic control method of electromagnetic injection armature muzzle velocity for rupture mitigation, which belongs to the field of electromagnetic launch, and comprises: S1, after the armature enters the deceleration track and injects the projectile separation current, the real-time speed, time, trigger module number and trigger time of the deceleration section power supply of the armature reaching the preset position are obtained; S2, according to the real-time speed, time, trigger module number and trigger time of the deceleration section power supply, the predicted value of the armature muzzle velocity is obtained; S3, according to the predicted value and set value of the armature muzzle velocity, the trigger module number and trigger time of the deceleration section power supply are controlled so that the armature muzzle velocity reaches the set value. The method can realize the precise control of the armature muzzle velocity, improve the safety of armature recovery, reduce the damage of the armature to the device track and the tokamak device; by reducing the dispersion of the armature muzzle velocity, the motion stability of the armature is improved, and the armature ablation is reduced.

Description

A dynamic control method for electromagnetic injection armature exit velocity for cracking mitigation

Technical Field

The invention belongs to the field of electromagnetic emission, and more specifically, relates to a method for dynamically controlling the exit velocity of an electromagnetic injection armature for cracking mitigation.

Background technique

Controlled fusion reactors are considered to be one of the most promising means to solve the energy crisis of mankind. Its core device is the Tokamak device, whose operating principle is to confine plasma of hundreds of millions of degrees in a vacuum chamber under high vacuum conditions to carry out fusion reactions. However, due to the fluctuation of physical factors and the limitations of the device's own design, the plasma in the Tokamak device sometimes breaks. If the broken plasma is not controlled, it will cause extremely serious damage to the inner wall of the device in a very short time. Therefore, measures must be taken to alleviate the rupture before the broken plasma causes harm (<=30ms).

At present, the main means to mitigate the plasma rupture of the Tokamak device is to inject a large amount of impurities. At the current stage, the latest impurity injection technology is the electromagnetic pellet injection (EPI) technology. The EPI technology is to place the projectile on the armature, use the electromagnetic railgun to launch the armature at high speed, and then separate the armature from the projectile before leaving the orbit, so as to achieve the purpose of high-speed projectile launch. EPI has the ability to launch projectiles at a speed of 2km/s, and the acceleration process is less than 2ms. If applied to rupture mitigation, it will greatly shorten the system response time and realize high-speed projectile injection, which is enough to make up for the lack of high-pressure gas propulsion and has the ability to achieve rupture mitigation in conjunction with the rupture prediction system.

The current EPI device mainly has two problems: the separation of the projectile and the armature and the safe recovery of the armature. The acceleration-deceleration two-stage electromagnetic launch injection device will be able to solve this problem well, such as the electromagnetic acceleration and deceleration two-stage electromagnetic injection device with an integrated track disclosed in the Chinese patent application number 202210373182.1. The acceleration section of the device can accelerate the armature and the projectile to the required high speed such as 2000m/s; the deceleration section feeds a reverse current, and the electromagnetic force hinders the armature from moving forward, and the armature is ejected at a low speed to facilitate safe recovery and prevent the high-speed armature from damaging the tokamak. The projectile is separated from the armature due to inertia at the moment of entering the deceleration section and keeps flying out at high speed. Due to the limitations of the tracks on both sides, the posture of the armature is relatively straight, and it will not be as severely skewed as the armature out of the barrel, which can ensure the shooting direction of the projectile after separation. However, the acceleration-deceleration two-stage electromagnetic launch injection device still has the problem that when the armature exits the barrel at a low speed, the armature is extremely unstable and has a large dispersion, and even cannot exit the barrel when the exit speed is too low.

Summary of the invention

In view of the above defects or improvement needs of the prior art, the present invention provides a method for dynamically controlling the armature exit bore velocity of electromagnetic injection for rupture mitigation, thereby solving the problem in the existing acceleration-deceleration two-stage electromagnetic injection technology that when the armature exit bore velocity is low in the deceleration stage, the armature exit bore velocity is extremely unstable and has a large dispersion, and may even fail to exit the bore when the exit bore velocity is too low.

To achieve the above object, according to a first aspect of the present invention, a method for dynamically controlling the armature exit velocity of electromagnetic injection for tokamak rupture mitigation is provided, wherein the electromagnetic injection is an acceleration-deceleration two-stage electromagnetic injection, and the method comprises:

S1, after the armature enters the deceleration track and injects the projectile separation current, obtain the real-time speed and time when the armature reaches the preset position and the number of trigger modules and trigger time of the deceleration section power supply; wherein the deceleration section power supply is used to provide current for the deceleration track;

S2, obtaining a predicted value of the armature ejection velocity according to the real-time speed, time, the number of trigger modules and the triggering time of the deceleration stage power supply;

S3, according to the predicted value and the set value of the armature ejection velocity, the triggering module number and the triggering time of the deceleration section power supply are controlled so that the armature ejection velocity reaches the set value.

According to a second aspect of the present invention, there is provided a dynamic control device for electromagnetic injection armature exit velocity for Tokamak rupture mitigation, wherein the electromagnetic injection is an acceleration-deceleration two-stage electromagnetic injection, and the device comprises:

The first processing module is used to obtain the real-time speed and time of the armature reaching the preset position and the number of trigger modules and the triggering time of the deceleration section power supply after the armature enters the deceleration track and injects the projectile separation current; wherein the deceleration section power supply is used to provide current for the deceleration track;

A second processing module is used to obtain a predicted value of the armature ejection velocity according to the real-time speed, time, and the number of trigger modules and triggering time of the deceleration section power supply;

The third processing module is used to control the triggering module number and triggering time of the deceleration section power supply according to the predicted value and the set value of the armature ejection velocity, so that the armature ejection velocity reaches the set value.

According to a third aspect of the present invention, there is provided an electromagnetic injection armature muzzle velocity dynamic control system for tokamak rupture mitigation, comprising: a computer readable storage medium and a processor;

The computer-readable storage medium is used to store executable instructions;

The processor is used to read the executable instructions stored in the computer-readable storage medium and execute the method as described in the first aspect.

According to a fourth aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to cause a processor to execute the method as described in the first aspect.

In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

1. The method provided by the present invention can realize the precise control of the armature exit velocity, control the exit velocity, improve the safety of armature recovery, and reduce the damage of the armature to the device track and the tokamak device; by reducing the dispersion of the armature exit velocity, the movement stability of the armature is improved, the armature ablation is reduced, and the injection accuracy of the projectile is improved.

2. The method provided by the present invention can realize the precise control of the armature exit velocity, and solve the problem that when the armature exit velocity is low in the deceleration stage, the armature exit velocity is extremely unstable and has large dispersion, or even cannot exit the barrel when the exit velocity is too low; thereby reducing the maintenance difficulty and cost of the acceleration-deceleration two-stage EPI device and improving the reliability of the two-stage EPI device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of an existing acceleration-deceleration two-stage electromagnetic launch injection device;

FIG2 is a schematic diagram of an X-shaped armature used in an acceleration-deceleration two-stage electromagnetic launch injection device;

FIG3 is a flow chart of a method for dynamically controlling armature ejection velocity according to an embodiment of the present invention;

FIG4 is a second flow chart of the armature ejection velocity dynamic control method provided by an embodiment of the present invention;

Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

1-high voltage diode; 2-acceleration capacitor; 3-acceleration capacitor switch; 4-acceleration outer rail; 5-projectile; 6-armature; 7-magnetic field; 8-acceleration-deceleration inner rail; 9-deceleration capacitor switch; 10-deceleration capacitor.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

The embodiment of the present invention provides a method for dynamically controlling the armature exit velocity of electromagnetic injection for tokamak rupture mitigation, wherein the electromagnetic injection is an acceleration-deceleration two-stage electromagnetic injection, and the method comprises:

S1, after the armature enters the deceleration track and injects the projectile separation current, obtain the real-time speed and time when the armature reaches the preset position and the number of trigger modules and trigger time of the deceleration section power supply; wherein the deceleration section power supply is used to provide current for the deceleration track;

S2, obtaining a predicted value of the armature ejection velocity according to the real-time speed, time, the number of trigger modules and the triggering time of the deceleration stage power supply;

S3, according to the predicted value and the set value of the armature ejection velocity, the triggering module number and the triggering time of the deceleration section power supply are controlled so that the armature ejection velocity reaches the set value.

It can be understood that the method provided by the present invention can be used for any acceleration-deceleration two-stage electromagnetic injection device, for example, the electromagnetic acceleration-deceleration two-stage electromagnetic injection device with an integrated track disclosed in the Chinese patent application number 202210373182.1 as shown in Figures 1-2.

Preferably, in step S1, the real-time speed of the armature when it reaches the preset position is obtained by using a plurality of groups of speed measuring magnetic probes arranged before and after the preset position.

Specifically, in step S1, the real-time velocity of the armature at the preset position is obtained through the armature exit velocity measurement system.

The armature ejection velocity measurement system includes a speed measuring magnetic probe, a data acquisition card, etc. The speed measuring magnetic probe is composed of a metal shell and an induction loop coil located at the end of the metal shell, and is distributed on the side of the electromagnetic injection device along the direction of the armature emission. When the armature passes through the magnetic probe, the magnetic field at the magnetic probe rises when the armature approaches the magnetic probe and decreases when it is away from the magnetic probe. The induced current generated on the magnetic probe coil is manifested as a forward pulse followed by a reverse pulse. By measuring the moment when the induced current of the magnetic probe passes through zero, the moment when the armature reaches the position of the magnetic probe can be measured, so a magnetic probe can obtain a set of time-displacement values of the armature movement. By placing multiple groups of magnetic probes, multiple groups of time-displacement values of the armature movement can be obtained, so that the approximate interval speed of the armature can be obtained. Similarly, by placing the positions of the two magnetic probes close enough, the instantaneous speed of the armature at this position can be approximately measured. The data acquisition card is used to collect the time-displacement information measured by the magnetic probe in order to draw the speed curve of the armature movement.

Preferably, in step S2, the real-time speed, time (moment), the number of trigger modules of the power supply and the trigger moment are input into a neural network model to obtain a predicted value of the armature ejection velocity;

The neural network model is trained with the number of trigger modules and trigger time of the power supply, the speed and time of the armature passing through a preset position as input, the armature ejection velocity as output, and the goal of minimizing the difference between the output armature ejection velocity and the given armature ejection velocity.

Preferably, the neural network model is CNN, LSTM or Transformer.

Specifically, in the training stage, the neural network model is trained with the number of trigger modules and trigger time of the power supply, the speed and time of the armature passing through the preset position as input, the armature exit velocity as output, and the minimum difference between the output armature exit velocity and the given armature exit velocity as the goal. In the application stage, the number of trigger modules and trigger time of the power supply, the speed and time of passing through the preset position are input into the trained neural network model to obtain the predicted armature exit velocity.

The complex nonlinear relationship between input parameters and output muzzle velocity is learned through the neural network model. The neural network model is trained through the training data set, and the model parameters are continuously adjusted through the optimization algorithm to improve the accuracy and stability of the model. At the same time, a comparative analysis is conducted on the neural network models using different algorithms to judge the quality of the training performance of each model. The model is tested and verified using an independent test data set to evaluate the performance and generalization ability of each model, and the best model is selected to predict the armature muzzle velocity.

The training process of the model is as follows: First, by doing many launch experiments (on the acceleration-deceleration two-stage electromagnetic injection device), the number of PFU modules and trigger time used in each test, the speed and time of the armature at the preset position, the armature exit velocity and other data are obtained to make a data set. At the same time, the data set is divided into three parts: training set, verification set, and test set. When training on the training set, the quantity that the model wants to output (i.e., the armature exit velocity) will first be separated as a label as the target of model training. Then the remaining data (i.e., the number of PFU modules and trigger time of the power supply in the deceleration stage, the speed and time of the armature at the preset position) will be used as the input of the model, and it will be input into the model to obtain the output. After that, the loss of the output and the label is calculated, and the training is carried out with the goal of minimizing the loss, so that the output of the model approaches the label value. The role of the verification set is to test the training effect of the model. Usually, the verification of the model and the training of the model are carried out alternately, that is, a verification is carried out after several rounds of training. When verifying, usually only the loss or accuracy of the model output and the verification label is calculated without any optimization. The model validation process can test the actual performance of the model and avoid overfitting. Usually, during training, the model parameters with the best performance in the validation set are saved for the final test. The test set is for the final test of the performance of the trained model. At this stage, no changes can be made to the test set and the model to avoid affecting the authenticity and accuracy of the results.

In step S3, according to the predicted value and the set value of the armature ejection velocity, the number of trigger modules and the triggering time of the power supply are controlled so that the armature ejection velocity reaches the set value.

Specifically, a speed comparison system can be used to compare the predicted value of the armature ejection velocity with a set value, and a speed dynamic control system can be used to control the number of trigger modules and the triggering time of the power supply so that the armature ejection velocity reaches the set value.

The speed comparison system includes a single chip microcomputer, etc. A group of speed measuring magnetic probes are arranged at an appropriate position after the armature track deceleration section to measure the speed of the armature at this position. The single chip microcomputer compares the predicted value of the armature exit velocity with the set armature exit velocity, and sends the armature velocity at this position and the comparison result with the set velocity to the speed dynamic control system. The set velocity used by the speed comparison system is determined through multiple firing experiments, and the set velocity meets the requirements of small dispersion of the armature exit velocity, and the armature exit velocity is as slow as possible without getting stuck.

The specific idea of the speed dynamic control system is to divide the deceleration current fed into the breech into two parts, inject the projectile separation current at the beginning of the deceleration section, and the size and injection time of the subsequent deceleration current are dynamically adjusted according to the armature speed detected in real time. The speed dynamic control system includes a single-chip microcomputer speed controller, a control switch, a power supply, etc. After the projectile separation current is passed to separate the projectile, the dynamic control of the armature exit velocity is mainly realized by the speed controller. After receiving the comparison result between the predicted value of the armature exit velocity transmitted by the speed comparison system and the set armature exit velocity, the speed controller controls the on and off of the switch and the type and size of the current passed according to the control strategy to achieve the acceleration and deceleration of the armature, thereby achieving the purpose of dynamically controlling the armature exit velocity. The control strategy of the speed controller is related to parameters such as the armature mass and the launch track structure, and can be determined through actual launch tests, such as PID.

Wherein, the acceleration capacitor 2 and the deceleration capacitor 10 are both pulse capacitors; the acceleration capacitor 2 is charged by the acceleration capacitor charger, and the deceleration capacitor 10 is charged by the deceleration capacitor charger, so that the acceleration capacitor 2 and the deceleration capacitor 10 can be charged with different voltages, and the acceleration capacitor 2 and the deceleration capacitor 10 are used to charge electric energy for storage and discharge when triggered to provide current to the acceleration section and the deceleration section respectively. The acceleration capacitor and the deceleration capacitor both include multiple pulse forming units, and the control of the current passing through the deceleration track can be achieved by controlling the number of deceleration capacitor trigger modules and the triggering time.

As shown in Figure 4, first select a suitable speed measurement point in the deceleration section, and at the same time, determine a set speed that satisfies the armature discharge and is as low as possible at this measurement point according to the type of armature used. After that, when the armature enters the deceleration section, first inject the projectile separation current to decelerate the armature initially, so that the projectile flies out first under the action of inertia. Then, when the armature reaches the speed measurement point, use the magnetic probe of the speed measurement system to measure its speed, and predict the armature discharge speed through the neural network model, and compare the predicted value of the armature discharge speed with the set armature discharge speed in the speed comparison system. Then, the speed dynamic control system decides to pass the acceleration or deceleration current and the current value passed according to the comparison result and the control strategy (realized by controlling the number of deceleration capacitor trigger modules and the triggering time), realize the acceleration and deceleration of the armature, and then realize the dynamic control of the armature discharge speed.

The embodiment of the present invention provides a dynamic control device for electromagnetic injection armature exit velocity for Tokamak rupture mitigation, wherein the electromagnetic injection is an acceleration-deceleration two-stage electromagnetic injection, and the device comprises:

The first processing module is used to obtain the real-time speed, time, and trigger module number and trigger time of the armature reaching the preset position after the armature enters the deceleration track and injects the projectile separation current;

A second processing module is used to obtain a predicted value of the armature ejection velocity according to the real-time speed, time, the number of trigger modules of the power supply and the triggering time;

The third processing module is used to control the number of trigger modules and the triggering time of the power supply according to the predicted value and the set value of the armature ejection velocity, so that the armature ejection velocity reaches the set value.

An embodiment of the present invention provides an electromagnetic injection armature muzzle velocity dynamic control system for tokamak rupture mitigation, comprising: a computer-readable storage medium and a processor;

The computer-readable storage medium is used to store executable instructions;

The processor is used to read the executable instructions stored in the computer-readable storage medium and execute the method described in any of the above embodiments.

An embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to execute any of the above methods.

It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims (5)

1. A method for dynamically controlling the armature exit velocity of electromagnetic injection for Tokamak rupture mitigation, wherein the electromagnetic injection is an acceleration-deceleration two-stage electromagnetic injection, characterized in that the method comprises: S1, after the armature enters the deceleration track and injects the projectile separation current, obtain the real-time speed and time when the armature reaches the preset position and the number of trigger modules and trigger time of the deceleration section power supply; wherein the deceleration section power supply is used to provide current for the deceleration track; S2, obtaining a predicted value of the armature ejection velocity according to the real-time speed, time, the number of trigger modules and the triggering time of the deceleration stage power supply; S3, according to the predicted value and the set value of the armature ejection velocity, the triggering module number and the triggering time of the deceleration section power supply are controlled so that the armature ejection velocity reaches the set value; In step S2, the real-time speed, time, number of trigger modules and trigger time of the power supply are input into a neural network model to obtain a predicted value of the armature ejection velocity; The neural network model is trained by taking the number of trigger modules and the triggering time of the power supply, the speed and time of the armature passing through the preset position as input, the armature ejection velocity as output, and the minimum difference between the output armature ejection velocity and the given armature ejection velocity as the goal; The neural network model is CNN, LSTM or Transformer. 2. The method according to claim 1, characterized in that, in step S1, the real-time speed of the armature when it reaches the preset position is obtained by using multiple groups of speed measuring magnetic probes arranged before and after the preset position. 3. A dynamic control device for electromagnetic injection armature exit velocity for tokamak rupture mitigation, wherein the electromagnetic injection is an acceleration-deceleration two-stage electromagnetic injection, characterized in that the device comprises: The first processing module is used to obtain the real-time speed and time of the armature reaching the preset position and the number of trigger modules and the triggering time of the deceleration section power supply after the armature enters the deceleration track and injects the projectile separation current; wherein the deceleration section power supply is used to provide current for the deceleration track; A second processing module is used to obtain a predicted value of the armature ejection velocity according to the real-time speed, time, and the number of trigger modules and triggering time of the deceleration section power supply; The third processing module is used to control the triggering module number and triggering time of the deceleration section power supply according to the predicted value and the set value of the armature ejection velocity, so that the armature ejection velocity reaches the set value; The real-time speed, time, trigger module number and trigger time of the power supply are input into the neural network model to obtain the predicted value of the armature ejection velocity; The neural network model is trained by taking the number of trigger modules and the triggering time of the power supply, the speed and time of the armature passing through the preset position as input, the armature ejection velocity as output, and the minimum difference between the output armature ejection velocity and the given armature ejection velocity as the goal; The neural network model is CNN, LSTM or Transformer. 4. A dynamic control system for electromagnetic injection armature muzzle velocity for Tokamak rupture mitigation, characterized by comprising: a computer readable storage medium and a processor; The computer-readable storage medium is used to store executable instructions; The processor is used to read the executable instructions stored in the computer-readable storage medium and execute the method according to any one of claims 1-2. 5. A computer-readable storage medium, characterized in that the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to execute the method according to any one of claims 1-2.