阅读说明：本技术 一种电子束扫描均匀度的自动调整系统及方法 (Automatic adjusting system and method for scanning uniformity of electron beam ) 是由 肖珺 陆洁平 许森飞 查军 于 2021-07-13 设计创作，主要内容包括：本发明涉及一种电子束扫描均匀度的自动调整系统及方法,包括电子加速器、扫描线圈、用于给扫描线圈供电的扫描电源,还包括放置于扫描线圈下方用于检测电子束剂量的剂量检测模块以及接收剂量检测模块信号的处理器,所述的剂量检测模块检测到电子束的扫描剂量信号发送至处理器,处理器内部对该信号进行处理并根据需要调整扫描电源对扫描线圈的输出驱动波形；通过改变扫描电源输出驱动波形实现自动调整。可以在电子束扫描不均匀时可以方便进行调节,能够自动调整,用户自己即可以操作,不需要返厂维修,操作方便快捷。(The invention relates to an automatic adjustment system and method of electron beam scanning uniformity, which comprises an electron accelerator, a scanning coil, a scanning power supply for supplying power to the scanning coil, a dose detection module arranged below the scanning coil and used for detecting the dose of the electron beam, and a processor for receiving signals of the dose detection module, wherein the dose detection module detects that scanning dose signals of the electron beam are sent to the processor, the processor processes the signals and adjusts the output driving waveform of the scanning power supply to the scanning coil according to the requirement; automatic adjustment is achieved by changing the output drive waveform of the scanning power supply. The electronic beam scanning device can be conveniently adjusted when the electronic beam scanning is uneven, can be automatically adjusted, can be operated by a user, does not need to be returned to a factory for maintenance, and is convenient and rapid to operate.)

1. The utility model provides an automatic adjustment system of electron beam scanning degree of consistency, includes electron accelerator (1), scanning coil (2), is used for scanning power supply (3) for scanning coil (2) power supply, its characterized in that still includes and places dose detection module (4) and the treater (5) of receiving dose detection module (4) signal that are used for detecting the electron beam dose below scanning coil (2), dose detection module (4) the scanning dose signal who detects the electron beam send to treater (5), treater (5) are inside handles this signal and adjusts scanning power supply (3) as required and to the output drive waveform of scanning coil (2).

2. The system for automatic adjustment of uniformity of electron beam scanning according to claim 1, wherein said dose detection module (4) is a CTA dose zone.

3. An automatic adjustment method for electron beam scanning uniformity is characterized in that the method comprises the steps of,

s1, starting the electron accelerator (1) to operate for a period of time, and supplying power to the scanning coil (2) by the scanning power supply (3) according to the initial driving waveform;

s2, the dosage detection module (4) transmits the dosage value detected in the time period to the processor (5) for processing;

s3, the processor (5) judges whether adjustment is needed according to the dose value of the time period, if so, the step S4 is carried out, and if not, the current state is kept unchanged;

s4, the processor (5) corrects the driving waveform of the scanning power supply (3) according to the dose value of the time period, and outputs a correction signal to the scanning power supply (3);

s5, the scanning power supply (3) drives the scanning coil (2) according to the corrected driving waveform in the next same time period.

4. The method for automatically adjusting uniformity of electron beam scanning according to claim 3, wherein step S2 is directly returned to step S5 to detect the dose value again through the dose detection module (4), and the detected value is inputted to the processor (5) until the dose value is within the deviation.

5. The method of claim 3, wherein the driving waveform is modified in step S4 by averaging the dose values during the time period, comparing the dose values at each time point with the average value, and increasing the PWM pulse width if the average value is higher than the average value and decreasing the PWM pulse width if the average value is lower than the average value.

6. The method of claim 3, wherein the driving waveform is modified in step S4 by selecting the dose value at the first time point as the standard value during the time period, comparing the dose value at each time point with the standard value, and modulating the PWM pulse width to increase if the modulation parameter is higher than the standard value and to decrease if the modulation parameter is lower than the standard value.

7. Method for automatic adjustment of the uniformity of electron beam scanning according to claim 5 or 6, characterized in that the pulse width of the modulation parameter PMW is increased or decreased according to a step pulse width set in the processor (5).

8. The method of claim 3, wherein the adjustment in step S3 is determined by taking the difference between the maximum dose value and the minimum dose value of the time period, and determining whether the difference is greater than a predetermined threshold, if so, the adjustment is required, otherwise, the adjustment is not required.

9. The method as claimed in claim 3, wherein the period of time in step S1 is selected as a period of time of a complete waveform.

10. The method of claim 3, wherein the dose detection module (4) selects a CTA dose zone.

Technical Field

The invention relates to the field of application of electron accelerators, in particular to an automatic adjustment system and method for scanning uniformity of an electron beam.

Background

The electron accelerator is a device for accelerating electrons by utilizing an induced electric field, and is widely applied to various fields in social life, most of electron accelerators carry out irradiation scanning, and the scanning irradiation function is realized by enabling an electron beam to run according to a set track through a scanning coil and a scanning power supply, and the scanning power supply is adopted to control the size of a magnetic field of the scanning coil, so that electrons passing through the coil are deflected, and the scanning irradiation function is realized.

However, in the actual use process, the radiation quality is greatly affected due to the fact that the radiation quality cannot reach the theoretical design level due to the influence of various factors such as an accelerator filament, an accelerating tube, an electron beam lens system, a scanning coil and a scanning power supply, and the scanning uniformity of the accelerator is different; various parameters of products on the market are determined when the products leave a factory, the scanning uniformity of the products is also determined, and the products are inconvenient to return to the factory for maintenance if adjustment is needed.

Disclosure of Invention

The technical problem to be solved by the invention is to provide an automatic adjusting system and method for electron beam scanning uniformity, which is convenient for modifying the scanning uniformity.

The technical scheme adopted by the invention for solving the technical problems is as follows: the utility model provides an automatic adjustment system of electron beam scanning degree of consistency, includes electron accelerator, scanning coil, is used for the scanning power supply of scanning coil power supply, still includes the dosage detection module who places and be used for detecting the electron beam dosage below scanning coil and the treater of receiving dosage detection module signal, dosage detection module detect the scanning dosage signal of electron beam and send to the treater, the treater is inside handles this signal and adjusts the output drive waveform of scanning coil to scanning power supply as required.

More specifically, the dose detection module selects a CTA dose zone.

An automatic adjustment method for electron beam scanning uniformity comprises the steps of,

s1, starting the electron accelerator to operate for a period of time, and supplying power to the scanning coil by the scanning power supply according to the initial driving waveform;

s2, the dosage detection module transmits the dosage value detected in the time period to the processor for processing;

s3, the processor judges whether adjustment is needed according to the dosage value of the time period, if so, the step S4 is carried out, and if not, the current state is kept unchanged;

s4, the processor corrects the driving waveform of the scanning power supply according to the dose value of the time period and outputs a correction signal to the scanning power supply;

and S5, the scanning power supply drives the scanning coil according to the corrected driving waveform in the next sample time period.

More specifically, after the step S5, the process returns to the step S2 to detect the dose value again by the dose detection module, and the detected value is input to the processor until the dose value is within the deviation.

More specifically, in the step S4, the drive waveform is corrected by averaging the dose values in the time period, comparing the dose values at the time points with the average value, and increasing the PWM pulse width if the average value is higher than the average value, or decreasing the PWM pulse width if the average value is lower than the average value.

More specifically, in the step S4, the method for correcting the driving waveform includes selecting the dose value at the first time point in the time period as the standard value, comparing the dose value at each time point with the standard value, increasing the PWM pulse width if the dose value is higher than the standard value, and decreasing the PWM pulse width if the dose value is lower than the standard value.

More specifically, the pulse width of the modulation parameter PMW is increased or decreased according to a step pulse width set in the processor.

More specifically, the adjustment in step S3 is determined by taking the difference between the maximum dose value and the minimum dose value of the time period, and determining whether the difference is greater than a set threshold, if so, the adjustment is required, and if not, the adjustment is not required.

More specifically, the period of time in step S1 is selected as a period of time of a complete waveform.

More specifically, the dose detection module selects a CTA dose zone.

The invention has the beneficial effects that: by using the system and the method, the electronic beam scanning can be conveniently adjusted when the scanning is uneven, the electronic beam scanning can be automatically adjusted, a user can operate the electronic beam scanning device by himself without returning to the factory for maintenance, and the electronic beam scanning device is convenient and fast to operate.

Drawings

FIG. 1 is a schematic diagram of an automatic adjustment system for uniformity of electron beam scanning according to the present invention;

FIG. 2 is a first logic flow diagram of a method for automatically adjusting uniformity of electron beam scanning according to the present invention;

FIG. 3 is a logic flow diagram of a second embodiment of the system for automatically adjusting uniformity of electron beam scanning according to the present invention;

FIG. 4 is a logic flow diagram of a modification of the present invention;

FIG. 5 is a schematic diagram of the drive waveform, current waveform, and dose waveform of the electron beam scan before correction according to the present invention;

FIG. 6 is a diagram of the driving waveform, current waveform and dose waveform of the electron beam scan after correction according to the present invention.

In the figure: 1. an electron beam accelerator; 2. a scanning coil; 3. a scanning power supply; 4. a dose detection module; 5. a processor.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

As shown in fig. 1, an automatic adjustment system for scanning uniformity of an electron beam includes an electron accelerator 1, a scanning coil 2, and a scanning power supply 3 for supplying power to the scanning coil 2, wherein the electron accelerator 1 generates an electron beam in its working mode, the electron beam passes through the scanning coil 2 to change the direction of the electron beam to form a scanning area, the scanning coil 2 is supplied with power by the scanning power supply 3, and a driving waveform of the scanning power supply 3 supplying voltage to the scanning coil 2 is as shown in fig. 1; the system also comprises a dose detection module 4 which is arranged below the scanning coil 2 and used for detecting the dose of the electron beams and a processor 5 which receives signals of the dose detection module 4, wherein the dose detection module 4 detects scanning dose signals of the electron beams and sends the scanning dose signals to the processor 5, the processor 5 processes the signals and adjusts driving waveforms of the scanning power supply 3 to the scanning coil 2 according to needs, and the uniformity of the scanned dose is high through adjustment.

Based on the above system, a method for automatically adjusting the scanning uniformity of the electron beam is formed, as shown in fig. 2,

s1, starting the electron accelerator 1 to operate for a period of time, and supplying power to the scanning coil 2 by the scanning power supply 3 according to the initial driving waveform, wherein the operation period of time can be idle or working period; which is the time period required for a complete waveform of the driving waveform, the initial driving waveform given by the scanning power supply 3 is shown in fig. 5.

S2, the dose detection module 4 transmits the dose value detected in the time period to the processor 5 for processing, wherein the dose detection module 4 selects a CTA (cellular triacetate) dose zone, the CTA dose zone can receive irradiation of the electron beam and collect the irradiation dose at the time point, and transmits the collected dose value signal to the processor 5 for processing, and the processor 5 has processing software for processing and comparing; the CTA dose band is placed in a scanning area under the condition that the electron accelerator is stopped, then the electron accelerator is started, and after the CTA dose band acquires signals, the electron accelerator is stopped to take out the CTA dose band.

S3, the processor 5 judges whether adjustment is needed according to the dose value of the time period, if so, the step S4 is carried out, and if not, the current state is kept unchanged;

the judgment method comprises the following steps:

taking the maximum dose value and the minimum dose value of the time period and calculating the difference, simultaneously manually setting a set threshold value in the processor 5, comparing the difference value with the set threshold value, if the difference value is greater than the set threshold value, indicating that the electron beam irradiation is in an uneven state in the time period, wherein the dose value needs to be adjusted, if the difference value is less than the set threshold value, indicating that the electron beam irradiation is approximately even in the time period, and at the moment, adjusting the dose value is not needed.

S4, the processor 5 corrects the driving waveform of the scanning power supply 3 according to the dose value of the time period, and outputs a correction signal to the scanning power supply 3;

the modification shown in fig. 4 can be implemented in two ways:

firstly, averaging the dose values collected in step S2 in the time period, then comparing the collected dose values at each time point with the average value, if the dose value at a certain time point is higher than the average value, increasing the modulation parameter PWM pulse width to decrease the dose value at the time point, and if the dose value at a certain time point is lower than the average value, decreasing the modulation parameter PWM pulse width to increase the dose value at the time point; in the method, after a period of time is collected and measured and calculated, the driving waveform is adjusted in the next period of time with the same duration.

Secondly, selecting the dose value collected at a first time point in the time period as a standard value, wherein the first time point can be randomly selected in each time point, then comparing the collected dose value at each time point with the standard value, increasing the PWM pulse width of the modulation parameter to reduce the dose value at the time point if the dose value at a certain time point is higher than the standard value, and decreasing the PWM pulse width to increase the dose value at the time point if the dose value at a certain time point is lower than the standard value; in the method, after a period of time is collected and measured and calculated, the driving waveform is adjusted in the next period of time with the same duration.

S5, the scanning power supply 3 drives the scanning coil 2 in the next similar time zone according to the corrected drive waveform (as shown in fig. 6), and the next similar time zone coincides with the time of the above time zone.

In the adjusting method, after the power is independently started to collect the drive waveform generated and corrected by the dose value, the drive waveform is used in the next starting operation.

Since there may be non-uniformity in the electron beam scanning after the adjustment method step S5, after step S5, the process returns to step S2 directly as shown in fig. 3 to detect the dose value again by the dose detection module 4, and the detected value is input to the processor 5 until the dose value is within the deviation, which is the set threshold value.

In the adjustment process of the loop, a step pulse width is set, and the pulse width of the modulation parameter PMW is increased or decreased according to the step pulse width in step S4.

In conclusion, by the system and the adjusting method, the dose uniformity of the electron beam scanning can be adjusted at any time, manual and automatic adjustment can be realized, the operation can be completed without high skill, factory return adjustment is not needed, the user can operate the system by himself, and the adjustment is simple, convenient and quick.

It is to be emphasized that: the above embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and all simple modifications, equivalent changes and modifications made to the above embodiments according to the technical spirit of the present invention are within the scope of the technical solution of the present invention.