51 results about "Hot cathode" patented technology

The invention relates to the technical field of plasma discharge control, in particular to a hot cathode filament discharge control method and system and controllable nuclear fusion equipment, and the method comprises the steps: obtaining a target arc current value and target discharge time of a hot cathode filament, and calculating a voltage feed-forward value of the hot cathode filament according to the target arc current value and the target discharge time; in response to a discharge control instruction of the thermionic cathode filament, calculating a voltage feedback value of the thermionic cathode filament according to the actual arc current value and the target arc current value of the thermionic cathode filament; and controlling the hot cathode filament to discharge according to the voltage feed-forward value and the voltage feedback value. Therefore, the problems that when the hot cathode filament discharges, due to the fact that the thermal inertia of the filament is large and a control method in the related technology is difficult to adapt to parameter changes under different discharge conditions, plasma discharge response is slow, and adaptability is poor are solved.

To provide a film-forming device capable of stabilizing a film thickness distribution of a protective film.SOLUTION: A film-forming device according to the present invention includes: a film-forming chamber; a holder for holding a substrate inside the film-forming chamber; an inlet pipe for introducing a carbon-containing source gas into the film-forming chamber; a cathode electrode with a filament shape; a first power supply that heats the cathode electrode by applying current; an anode electrode provided around the cathode electrode; a second power supply that generates a discharge between the cathode electrode and the anode electrode; a third power supply that applies the potential difference between the cathode electrode or the anode electrode and the substrate; an ionization region, in which the gas is ionized by the discharge; and an acceleration region, in which the ionized gas is accelerated by the potential difference, in which a soft magnetic cylinder is provided around the acceleration region.SELECTED DRAWING: Figure 1

The invention discloses a thermionic cathode ionization gauge anode and cathode voltage automatic adjusting circuit, which is characterized in that a cathode stable emission control module emits electrons after a cathode reaches a red hot state, and the electrons move towards the anode under the traction of anode high voltage under a vacuum condition and flow to a cathode stable emission feedback circuit; after the first sampling voltage is compared with a preset voltage, the power of the heating cathode filament is adjusted to adjust emission electrons, and electron emission current is stabilized; and the anode voltage stabilization module adjusts the voltage output of the power supply module through the voltage division sampling circuit and compares the second sampling voltage with the standard voltage, if the anode voltage becomes large or small, the second sampling voltage is adjusted to output voltage through the voltage stabilization circuit, the output voltage is input to the high-frequency transformation primary side of the transformer, then the voltage is accompanied, a voltage loop is formed, and the anode voltage is stabilized. The circuit realizes automatic adjustment of the anode voltage and the cathode voltage of the hot cathode ionization gauge, so that the anode voltage and the cathode voltage are stable, and the vacuum test precision of the hot cathode ionization gauge is improved.

[Problem] To provide novel technology. [Solution] One aspect of the present invention provides a thermionic cathode. The thermionic cathode includes an electron source and a plurality of grids. The electron source is configured to emit electrons when heated. The plurality of grids have through-holes that allow electrons emitted from the electron source to pass in a predetermined direction. At least one of the grids is configured to reduce the movement speed of the electrons.

The invention discloses a beam spot adjusting method and an electron accelerator, the electron accelerator comprises an anode potential adjusting device and an electron extraction device, a hot cathode of the electron accelerator is arranged on the electron extraction device, and the beam spot adjusting method comprises the following steps: acquiring physical parameters of an accelerating tube of the electron accelerator; calculating the beam waist position of the electron beam bunch according to the physical parameters of the accelerating tube; the control quantity of an anode potential adjusting device is obtained according to the girdling position; and adjusting the beam spot size of the outlet of the accelerating tube by using the control quantity. According to the invention, the extraction electric field distribution can be obtained, the purpose of controlling the beam envelope is achieved, so that the electron beam bunch safely arrives at the outlet of the electron accelerator, and the dynamic adjustment of the accelerator extraction outlet beam spot size within a certain range is realized by controlling the potential difference between the cathode and the anode.

To stably form an insulating film of high quality in a reactive ion plating apparatus and method.SOLUTION: In the reactive ion plating apparatus 10, an evaporation material 24 stored in a crucible 20 is heated and evaporated by an electron gun 22. In addition, the ionization power Wd is supplied to the crucible 20 as an anode and the hot cathode filament 34 that emits thermoelectrons as a cathode. Accordingly, the plasma 100 is induced. Further, the reactive gas is introduced into the vacuum chamber 12 through the hollow anode 46, and the hollow anode power Wh is supplied to the hollow anode 46. Accordingly, the hollow anode plasma 200 is induced. A hollow anode filament 48 is provided at a gas discharge port of the hollow anode 46. The hollow anode filament 48 becomes a stable anode by being heated by Joule heat.SELECTED DRAWING: Figure 1

The invention discloses a vacuum measuring tool and a vacuum degree measuring method, and the vacuum measuring tool comprises a measuring circuit which comprises a power supply which is a constant-voltage constant-frequency AC power supply; a resistive element; the current detection element is connected in series with the resistance element and is used for acquiring a current measurement value of the measurement circuit; the capacitor assembly is connected with the resistor element in series; a medium space between polar plates of the capacitor assembly is used for being communicated with a to-be-measured space, a current measurement value collected by the current detection element is in positive correlation with a capacitance value of the capacitor assembly, and the capacitance value of the capacitor assembly is in positive correlation with the vacuum degree of the to-be-measured space. According to the invention, the capacitor assembly is adopted to form the measurement circuit, the conversion from the collected current measurement value to the vacuum degree is realized, the device can be suitable for the measurement in different vacuum states, the precision is high, the integration degree is high, the space is saved, and the system complexity and the maintenance cost are reduced; and the technical barrier that a hot cathode vacuum gauge receives hot electrons is effectively avoided, and the problem that a high-vacuum measuring tool is short in service life is fundamentally solved.

The invention discloses a hot cathode for a vacuum device and a preparation method and application of the hot cathode. The structure of the hot cathode comprises a cathode substrate and an emission active material combined on the cathode substrate; wherein the cathode substrate is of a porous structure, and the cathode substrate is made of a mixture of chromic oxide and tungsten; and the emission active material is scandium-containing barium aluminate. According to the scheme, the problem that the requirement of a current high-power vacuum electronic device for a low-working-temperature and high-emission-current-density electron source cannot be met is well solved.

This invention relates to the field of aerospace propulsion technology, and in particular to an oxygen-resistant Hall thruster electric propulsion system, comprising a Hall thruster, a radio frequency neutralizer, a power processing unit, a working propellant storage and supply system, and an integrated electronic control system. This invention establishes an electrical connection between the Hall thruster and the radio frequency neutralizer, directly connecting the collecting electrode to the negative terminal of a high-voltage power supply, eliminating the holding electrode and its independent power supply branch. Simultaneously, it combines a dual-path working propellant supply structure with oxidation-resistant conductive materials for the anode and collecting electrode. This allows the radio frequency neutralizer to rapidly establish a plasma electron source without the need for traditional hot cathode preheating. After the Hall thruster ejects the ion beam, electrons are automatically extracted based on the potential gradient. This not only reduces the complexity of the system's power supply structure and improves the discharge stability and electron compensation capability in low-purity working propellants and oxygen-containing environments, but also enhances the system's oxygen-resistant lifetime and rapid start-up performance in low Earth orbit oxygen-rich environments.

The present application discloses a long-life X-ray pulse beacon device based on a nuclear battery, comprising an X-ray pulse source and a power module connected to the X-ray pulse source. The X-ray pulse source comprises: a first housing; a beta radiation source disposed within the first housing for generating beta particles; a transmissive thin-film hot cathode disposed within the first housing for receiving bombardment from the beta particles to generate thermal electrons; an anode target disposed within the first housing for receiving bombardment from the thermal electrons from the transmissive thin-film hot cathode to generate X-rays; and a grid disposed within the first housing between the beta radiation source and the transmissive thin-film hot cathode. The power module applies a pulse voltage between the beta radiation source and the grid, causing the beta particles to periodically pass through the grid and bombard the transmissive thin-film hot cathode. The present application can emit stable X-ray pulse signals that can be accurately captured and identified by detectors carried by spacecraft, meeting space positioning and navigation requirements.

The invention provides a composite film M-type hot cathode and a preparation method thereof. The composite film layer M-type hot cathode comprises a barium tungsten cathode substrate, a Re3W alloy phase barrier layer and a noble metal surface layer, and the Re3W alloy phase barrier layer is formed between the barium-tungsten cathode substrate and the noble metal surface layer. The composite film layer M-type thermionic cathode can effectively prevent alloying between the tungsten substrate and the precious metal film layer, so that the emission capability of the cathode is improved, and the service life of the cathode is prolonged.

This invention discloses a novel welding machine, comprising: a welding frame, the welding frame including a support frame, a sealed door on the front of the support frame, a welding chamber at the upper end of the inner cavity of the support frame, and a welding table at the bottom of the inner cavity of the welding chamber. This invention belongs to the field of welding machine technology. The purpose of this invention is to solve the problems of traditional hot cathode electron beam welding machines in the prior art, where the hot cathode requires continuous preheating, has a long start-up time, and still needs to maintain a high temperature in standby mode. The technical effect achieved is: using a directional carbon nanotube array microbeam emitter as a cold cathode, utilizing the field emission principle of carbon nanotubes, an electric field is applied between the grid and the cathode to allow electrons to escape from the tip of the carbon nanotube through quantum tunneling effect, without heating the cathode to a high temperature, achieving millisecond-level instantaneous start-up, solving the drawback of traditional welding machines requiring 5-10 minutes of preheating, and significantly improving work efficiency and equipment response speed.

The invention discloses a long pulse debugging method for a large-area thermionic cathode ion source, and belongs to the technical field of thermionic cathode ion sources, and the method comprises the steps: carrying out the air inlet vacuum debugging after the ion source is assembled; the insulation and voltage endurance capability is improved through cold high-voltage exercise; turning off high voltage, lighting a lamp filament, applying arc voltage, and cleaning the cavity through arc chamber plasma discharge; the extraction voltage is gradually applied to perform beam extraction exercise, and beam transmission is optimized through diversion coefficient scanning; and finally, the diversion coefficient is reduced, the pulse width is prolonged, and long-pulse discharge debugging is realized. According to the method, a systematic debugging process from vacuum verification, insulation and voltage resistance, cavity cleaning to beam extraction and long pulse discharge is established, the stability and reliability of the ion source can be effectively improved, the breakdown risk is reduced, and a technical basis is provided for long-term stable operation of a large-area hot cathode ion source in the future.

To provide an indirect heated cathode capable of shortening the time up to a start of radiation of thermoelectrons, and a method of manufacturing the indirect heated cathode in which a heat absorption layer which has a uniform thickness can be easily manufactured.SOLUTION: An indirect heated cathode 10 comprises a cathode sleeve 1, a heater 2 arranged at a hollow part of the cathode sleeve 1, a black heat absorption layer 4 covering a hollow part inner surface of the cathode sleeve 1, and a cathode base body 3 carrying an electron emission substance arranged at the cathode sleeve 1. The black heat absorption layer 4 consists of a particulate substance including tungsten and aluminum oxide. The black heat absorption layer 4 is formed by arranging rod-like alumina ceramics, and a first tungsten heater and a second tungsten heater in the hollow part of the cathode sleeve 1 and heating it in a vacuum atmosphere.SELECTED DRAWING: Figure 1

This invention discloses an open-tube miniature X-ray tube with adjustable anode and its experimental evaluation platform, belonging to the field of miniature micro-focal spot X-ray tube technology. The system comprises an open-tube miniature X-ray tube system and an experimental platform. The open-tube miniature X-ray tube system includes a hot cathode filament, an electrostatic lens focusing system, and an anode target. The experimental evaluation system includes a vacuum chamber and interfaces for electrical input and vacuum input that cooperate with the vacuum chamber. The anode-cathode distance can be adjusted using the positioning holes on the electron optics system. The experimental evaluation system fixes the electron optics system and provides the necessary experimental conditions such as a high vacuum environment, accelerating voltage, and heating current. This invention enables open-tube experiments with adjustable anode for miniature X-ray tubes. Compared to closed-tube experiments, open-tube experiments facilitate adjustments to the miniature tube design and reduce experimental costs.

The application relates to a non-stoichiometric carbide doped tungsten-based thermionic cathode material and a preparation method thereof, and belongs to the technical field of refractory metal cathode materials. Zirconium carbide, hafnium carbide and titanium carbide are respectively mixed with their respective hydrides or graphite by using a high-energy ball milling technology, and then mixed with tungsten powder to obtain non-stoichiometric carbide doped tungsten powder with C "vacancies" or non-stoichiometric carbide doped tungsten powder with metal element "vacancies", and then the non-stoichiometric carbide doped tungsten-based thermionic cathode is prepared by means of pressing, vacuum sintering at 1600-2100 DEG C. The thermionic cathode material has the advantages of simple preparation process, high cathode density of 99%, and the highest emission current density of 1.63 A / cm 2 at 1600 DEG C, which is about 30% higher than that of a standard stoichiometric carbide, and the thermionic emission performance is 3 times higher than that of a pure metal cathode.

The application belongs to the field of space electric propulsion, and particularly relates to a propellant-free hot cathode for electric propulsion, which comprises an emitter material, an emitter, a support structure, N heat shields, an extraction grid, a base and an outer shell; the emitter is used to generate heat and heat the emitter material, the emitter material is used to heat and emit electrons; the support structure is used to reduce heat dissipation of the emitter; the N heat shields are used to reduce heat radiation of the emitter to the outside; the cathode emitter heater is integrated with the emitter material, and is isolated by the heat shield design, so that the emitter material can reach a temperature sufficient to meet the emission current under as much heating power as possible; and an extraction grid structure is designed, which can apply a certain electric field to the surface of the emitter, improve the emission current density of the emitter, relieve the space charge effect, and reduce the hindrance of the emitted electrons of the emitter to the process of being extracted to the thruster plume to participate in neutralization.

The invention discloses a high-charge heavy-ion high-energy-intensity laser. A high-intensity single-charge heavy-ion beam is obtained by transversely colliding a single-charge heavy-ion beam injection section with a low-speed multi-surface side-by-side correlation surface electron flow containing an unionized atom return channel; a high-intensity single-charge heavy ion beam is converted into a high-intensity high-charge heavy ion beam with the ionization degree of mu by adopting a flat runway-shaped high-speed multi-surface side-by-side correlation surface electron flow transverse collision high-charge heavy ion ionization ring with two high-charge ionization regions; high-charge heavy ion high-energy laser and heavy ion beam emission is realized by adopting a flat runway-shaped high-speed multi-surface side-by-side correlation surface electron flow to transversely collide with a high-charge heavy ion excitation ring. The intensity of surface electron flow, heavy ion beam and laser beam can be greatly improved by adopting the electrified thermionic cathode which is connected in parallel with the high-capacity super capacitor and has the width increased by more than five times. According to different laser wavelengths and powers, various practical purposes can be achieved from obtaining of a high-contrast holographic image of an internal atomic structure of a organism to serving as a novel high-energy strong laser weapon.

An arc chamber for an ion source defines a chamber volume, and a target material is disposed within the chamber volume. The target material includes a dopant species and may be included in the target member. An indirect heating cathode is disposed within the chamber volume and ionizes the source gas within the chamber volume thereby defining a plasma having plasma thermal radiation. The target heater selectively heats the target material independently of plasma thermal emission associated with the plasma. The target heater may be a resistive heating element, an induction heating element, a halogen heating element, or a laser configured to selectively heat at least a portion of the target member. The target member may be composed of a solid dopant material, or may include a liquid dopant material.

An x-ray tube includes a thermionic cathode generating an electron beam propagating from the cathode to a target along a beam axis. The x-ray tube has apertures in the form of a control electrode with a first aperture opening, a focusing electrode with a second aperture opening and a beam shaping electrode with a third aperture opening. The first aperture opening is smaller than the emission surface and has a contour rotationally symmetric with respect to the beam axis. The second aperture opening is larger than the first aperture opening and has a contour rotationally symmetric with respect to the beam axis. The third aperture opening has a contour which is aligned with an xy plane and non-rotationally symmetric with respect to the beam axis. The X-ray tube has a simple structure for generating an electron beam where the number of electrons can be varied easily over a wide range.

The invention discloses a dynamic gear shifting processing method and system based on a hot cathode ionization vacuum gauge, and relates to the technical field of vacuum measurement, and the method comprises the steps: obtaining a compensation value based on an improved ion current collection and amplification circuit, and obtaining the current vacuum degree through the calculation of the compensation value; judging the dynamic change condition of the measurement environment according to the obtained gear shifting requirement, and judging whether the gear shifting condition is met or not under the corresponding dynamic change condition; when the gear shifting condition is met, the corresponding gear interval is entered, and the vacuum degree after the preset time under the corresponding dynamic change condition is obtained based on the current vacuum degree; and the phenomena of blockage, repeated values, numerical value loss and the like of the vacuum gauge in the gear shifting process are solved.

The invention relates to the field of power supply terminal management, is used for solving the problem of lack of a technical scheme capable of simultaneously deconstructing a power supply operation effect in dynamic and instantaneous multi-dimension and multi-parameter angles in the prior art, and particularly relates to a safety monitoring method and system for a negative high-voltage power supply terminal of a thermionic cathode X-ray tube. Comprising a multi-source data monitoring module, a data slice analysis module, a dynamic series analysis module, an operation situation judgment module and an early warning output module. According to the method, the data is primarily processed in an edge calculation mode, the processed data is returned and then is further analyzed, edge and cloud collaborative processing is realized, data processing benefits are improved, analysis is carried out on two different dimensions including an instantaneous dimension and a dynamic dimension through different analysis modes, and the data processing efficiency is improved. And synchronous analysis is carried out on different parameters, so that operation safety monitoring analysis of different dimensions and different parameter angles is realized, and the comprehensiveness and accuracy of safety monitoring of the negative high-voltage power supply terminal are improved.

The application discloses a high-sensitivity hot cathode ionization gauge which can be used in a strong magnetic field environment and has a lower lower limit of measurement, and the hot cathode ionization gauge mainly comprises a cathode filament, an anode grid, an ion collecting electrode and a metal shell; wherein the cathode filament is a spiral thick filament structure and is used for resisting the Ampere force in the strong magnetic field; the anode grid is a spiral structure or a cage structure, which comprises a left anode grid and a right anode grid and is symmetrically arranged with the cathode filament as the center; the ion collecting electrode is a metal filament structure, which comprises a left ion collecting electrode and a right ion collecting electrode; the metal shell is a cylindrical structure, and the electric potential of the metal shell is arranged to be grounded; the cathode filament, the anode grid, the ion collecting electrode and the metal shell are coaxially arranged, and when working in the magnetic field environment, the electrode axis arrangement direction is parallel to the magnetic field direction. Compared with the traditional hot cathode ionization gauge used in the strong magnetic field environment, the application can effectively prolong the service life of the cathode filament, improve the sensitivity of the ionization gauge, and extend the lower limit of measurement to 10 ‑9 Pa.

The invention provides an assembly tool and an assembly method for a hot cathode filament, the assembly tool comprises a half base and a welding pressing block tool which are symmetrically arranged left and right, the half base is provided with a filament groove and two pin limiting tables, the size of the filament groove is accurately matched with the diameter of the filament, and an annular step of a conductive pin is limited on the pin limiting tables; the welding pressing block tool comprises a first pressing block and a second pressing block, and the first pressing block is used for limiting the transverse position of the lamp filament; one end of an L-shaped convex block on the second pressing block presses the lamp filament in the lamp filament groove, and the other end of the L-shaped convex block reserves an enough space, so that the lamp filament can be welded conveniently; and the welding of the other welding end of the lamp filament is realized by exchanging the positions of the first pressing block and the second pressing block. According to the invention, the symmetrically arranged Haff bases effectively control the position and deformation of the lamp filament in the assembly process, the unique design of the welding pressing block tool limits the transverse and longitudinal movement of the lamp filament, the welding space is reserved, and the position accuracy and consistency of lamp filament assembly are remarkably improved.

The application discloses a radial electron beam staggered grid structure traveling wave amplifier, which comprises coaxial staggered grid leaves with different radii and made of metal at the lower side and the upper side of upper and lower metal ring shells, the lower side and the upper side of the grid leaves are staggered, and a cavity is formed between the lower side and the upper side of the grid leaves, thereby forming a slow wave structure. Electromagnetic waves are injected from the cavity between two adjacent grid leaves at the lower side of the upper metal ring shell or the upper side of the lower metal ring shell near a hot cathode through an input structure as a signal to be amplified, the electromagnetic waves are transmitted along the cavity in the coaxial staggered grid and interact with electron beams transmitted along the radial direction, thereby converting electron kinetic energy into electromagnetic wave energy, amplifying the input electromagnetic wave signal, and outputting the amplified electromagnetic waves from the lower metal ring shell or the upper metal ring shell through an output structure. The application has the characteristics of high interaction efficiency, high output power, high coupling impedance and simple structure.

The invention discloses an inverted magnetron which comprises a supporting heat dissipation assembly, a permanent magnet, a resonant cavity, an external cathode (a hot cathode or a cold cathode can be selected), an antenna and a power supply line. The supporting heat dissipation assembly is composed of a ceramic supporting piece, a heat dissipation copper shell, an anode heat conduction upper shell, an anode heat conduction lower shell, a cathode upper cover and a cathode lower cover which are coaxial, the ceramic supporting piece is fixed to the center of the heat dissipation copper shell, the cathode upper cover and the cathode lower cover are arranged at the upper end and the lower end of the heat dissipation copper shell respectively, and the anode heat conduction shell is externally connected with the heat dissipation copper shell and internally connected with the resonant cavity. The external cathode surrounds the inner side of the ceramic supporting piece, the two ends of the external cathode are connected with the cathode cover, and the resonant cavity is arranged in the external cathode and makes contact with the anode heat conduction shell. The antenna is led upwards from the resonant cavity, and the power supply line is connected with the cathode cover to supply power. According to the scheme, miniaturization of the resonant cavity is achieved through inverted layout, efficient heat dissipation and an axial uniform magnetic field are combined, high-power millimeter waves are stably output at low cost, and the resonant cavity is suitable for the fields of communication, radar and the like.

The invention discloses an ion flow measurement method and a measurement circuit for an extremely-high thermal cathode ionization gauge, and relates to the technical field of ion flow measurement, and the method comprises the steps: obtaining a demand range of ion flow measurement, and dividing the demand range into a first ion flow range and a second ion flow range; the ion flow measurement in the first ion flow range is completed through a preset first measurement mode, and the ion flow measurement in the second ion flow range is completed through a preset second measurement mode; measurement of electron currents of different measurement sections is achieved through the measurement circuit arranged based on the measurement method, the problem that in high vacuum measurement, a traditional ion current measurement circuit is poor in precision in ultrahigh measurement is solved, and the blank in ultrahigh vacuum measurement is filled.

A method for rejuvenation of a cathode in an electron-beam system is disclosed, wherein the cathode comprises an electron emitter embedded in a carbon guard ring, the method comprising: setting a pressure in a rejuvenation atmosphere surrounding the cathode to a rejuvenation pressure; and heating the cathode such that the carbon guard ring attains a rejuvenation temperature; wherein the rejuvenation pressure and the rejuvenation temperature are selected so that a rate at which material is removed from the carbon guard ring is higher than a rate at which material is removed from the electron emitter. Removal of material from the carbon guard ring is effected by a reaction between the carbon guard ring and a first gas comprised in the rejuvenation atmosphere. A method of operating an electron beam system involving such rejuvenation is also disclosed, as well as a computer program that when executed by one or more processors causes an X-ray source to perform the method.

The application discloses a kind of composite vacuum gauge circuit systems based on module multiplexing, the circuit system is configured as drivable vacuum sensor, vacuum sensor is Pirani sensor and hot cathode ionization sensor, circuit system includes: power supply circuit, filament heating circuit, adjustable high voltage circuit, ion current measurement circuit, voltage measurement circuit, analog-digital conversion circuit, wherein, single-chip microcomputer is configured as: starting Pirani sensor, control adjustable high voltage circuit and ion current measurement circuit are not enabled;Current vacuum degree is obtained based on Pirani sensor, if vacuum degree is greater than or equal to preset threshold, then continue to use Pirani sensor to measure vacuum degree;If vacuum degree is less than preset threshold, then enable adjustable high voltage circuit and ion current measurement circuit, and use hot cathode ionization sensor to measure vacuum degree.By the switchable circuit system controlled by single-chip microcomputer, the driving and measurement of two kinds of principle different vacuum sensors by a set of circuit system are realized.

The application discloses a kind of beam spot adjusting method and electron accelerator, the electron accelerator includes a anode potential adjusting device and an electron extraction device, the hot cathode of the electron accelerator is located on the electron extraction device, the beam spot adjusting method includes: obtaining the accelerating tube physical parameter of electron accelerator;According to the beam waist position of accelerating tube physical parameter calculation electron bunch;According to the control quantity of anode potential adjusting device obtained by beam waist position;The beam spot size of accelerating tube outlet is adjusted using the control quantity.The application can obtain the extraction electric field distribution, achieve the purpose of controlling beam envelope, so that the electron bunch safely reaches the outlet of electron accelerator, while controlling the potential difference between cathode and anode, realizing the dynamic adjustment of accelerator extraction port beam spot size within a certain range.