CN112240993A - Evaluation system and method for compact cyclotron magnetic field stability measurement - Google Patents
Evaluation system and method for compact cyclotron magnetic field stability measurement Download PDFInfo
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Abstract
The invention discloses an evaluation system for measuring the magnetic field stability of a compact cyclotron, which comprises a magnetic field measurement power supply system stability evaluation unit, a magnetic field measurement water cooling system stability evaluation unit, a magnetic field measurement environment temperature and humidity stability evaluation unit, a magnetic field measurement data acquisition communication system stability evaluation unit and a magnetic field measurement motion positioning device stability evaluation unit; also disclosed is an evaluation method: measuring the influence of the operating environment on the magnetic field stability of the compact cyclotron; measuring the influence of data acquisition communication equipment on the magnetic field stability of the compact cyclotron; measuring the magnetic field stability of the compact cyclotron by the measuring and moving positioning device; the invention combines the method of limiting the absolute value of the stability of the magnetic field of a single factor and the method of limiting the absolute value of the stability of the magnetic field of a comprehensive factor, and the method supports and depends on each other, thereby solving the technical problems that the field is lack of research on the stability of the measurement of the magnetic field for a long time and is not systematic enough.
Description
Technical Field
The invention belongs to the field of cyclotrons, and particularly relates to an evaluation method suitable for measuring the magnetic field stability of a compact small-sized cyclotrons.
Background
Compact cyclotrons are widely used in hospitals for isotope production, typically at energies of 10MeV to 20 MeV. The magnetic field intensity is generally 400Gs-20000Gs, the air gap between the magnetic poles of the compact type small cyclotron is small, the required ampere-turns are smaller, the energy consumption can be greatly saved, and the condition that the beam is struck on the magnetic poles and is lost is easily generated when the axial focusing is smaller. With the proposal of the magnet design concept in the deep valley region, the axial focusing of the cyclotron is greatly improved. In practical application, the defects of shrinkage cavities, inclusion and the like in the cover plate exceed the technical requirements in the casting process, and the problems affect the magnetic performance of the material and further affect the distribution of a magnetic field. If the factors such as internal defects of the main magnet, machining errors, installation errors and the like exist, the magnetic field distribution of the central plane is obviously influenced, and therefore, whether the magnetic field of the main magnet meets the physical design requirements or not is very necessary to verify through magnetic field measurement.
For most compact small-sized cyclotrons to carry out magnetic field measurement, the magnetic field measurement precision requirement reaches 10-4At present, the magnetic field measurement attention of the compact type small-sized cyclotron is mainly focused on the magnetic field measurement precision, the research on the magnetic field measurement stability is less and is not systematic enough, the magnetic field measurement stability is determined by multiple influencing factors, and in order to obtain a magnetic field measurement result with higher precision, the main magnetic field influencing factors need to be comprehensively analyzed.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides an evaluation method suitable for the magnetic field measurement stability of a compact type small cyclotron, which comprehensively considers the main factors influencing the stability in the magnetic field measurement process of the compact type small cyclotron, and controls a plurality of factors influencing the magnetic field stability in the magnetic field measurement within a proper range according to the actual magnetic field measurement error requirement so as to obtain an accurate and effective magnetic field measurement result.
An evaluation system for magnetic field stability measurement of a compact cyclotron comprises a magnetic field measurement power supply system stability evaluation unit, a magnetic field measurement water cooling system stability evaluation unit, a magnetic field measurement environment temperature and humidity stability evaluation unit, a magnetic field measurement data acquisition communication system stability evaluation unit and a magnetic field measurement motion positioning device stability evaluation unit; the method is characterized in that:
the magnetic field measurement data acquisition communication system stability evaluation unit and the magnetic field measurement movement positioning device stability evaluation unit respectively comprise stability evaluation on self factors and stability evaluation on comprehensive factors; stability evaluation units of the power supply system, the water cooling system and the environment temperature and humidity system provide stability evaluation of comprehensive factors for a data acquisition communication system stability evaluation unit; and the stability evaluation units of the power supply system, the water cooling system, the ambient temperature and humidity system and the data acquisition and communication system provide stability evaluation of comprehensive factors for the stability evaluation unit of the motion positioning device.
The power supply system stability evaluation unit comprises a cyclotron main magnet power supply system stability evaluation module and a controller power supply system stability evaluation module; the stability evaluation unit of the data acquisition communication system comprises a Hall probe stability evaluation module, a gaussmeter stability evaluation module, an optical fiber-to-serial port transponder stability evaluation module and a communication equipment stability evaluation module; the motion positioning device stability evaluation unit comprises a magnetic meter stability evaluation module, an encoder stability evaluation module and a circular grating stability evaluation module.
An evaluation method of an evaluation system for compact cyclotron magnetic field stability measurement is characterized in that: the method comprises the following steps:
measuring the influence of an operating environment on the magnetic field stability of the compact cyclotron;
measuring the influence of data acquisition communication equipment on the magnetic field stability of the compact cyclotron;
thirdly, measuring the magnetic field stability of the compact cyclotron by the measuring motion positioning device;
the operation environment comprises a magnetic field measurement power supply system, a magnetic field measurement water cooling system, a magnetic field measurement environment temperature and humidity, and the data acquisition communication equipment comprises a Hall probe, a gaussmeter, an optical fiber-to-serial port transponder and magnetic field measurement communication equipment; the motion positioning device comprises a magnetism measuring instrument, an encoder and a circular grating;
the method is characterized in that: the stability test of the data acquisition communication equipment is carried out under the condition of ensuring the stable operation environment of the compact cyclotron; the stability test of the magnetic field motion system is carried out under the condition of ensuring the stability of the operation environment of the compact cyclotron and the stability of the data acquisition communication equipment;
the first step comprises the following processes:
1) measuring the influence of power supply stability on the magnetic field stability of a compact cyclotron
The power supply is tested for 24 hours, the testing time comprises power utilization peaks and valleys, the time T is taken to be greater than the actual magnetic field measuring time T0 after the testing is finished, and according to a B-I curve of a magnetic field, the power supply influence factor sensitivity S1 is B (delta I)/B (I), wherein delta I is the change of current relative to a set value I in the testing time period T;
2) measuring the influence of the stability of a water cooling system on the stability of the magnetic field of a compact cyclotron
Collecting magnetic pole temperature through a thermistor, synchronously carrying out temperature collection and power supply test in 1, and taking time T to be greater than actual magnetic field measurement time T0, wherein magnetic pole temperature influence factor sensitivity S2 is k1 delta Tepole/Tepole, wherein delta Tepole is the change of the magnetic pole temperature relative to an initial temperature value Tepole in a test time period T, and proper k1 needs to be selected according to magnetic pole materials and influence effects because the magnetic pole temperature is an indirect measurement quantity relative to a magnetic field;
3) measuring the effect of ambient temperature stability on magnetic field stability for compact cyclotrons
The temperature of the magnetic yoke is collected through a thermistor, the temperature collection is carried out synchronously with the power supply test in the step 1, the time T is greater than the actual magnetic field measurement time T0, the magnetic yoke temperature influence factor sensitivity S3 is k2 delta Teyoke/Teyoke, wherein delta Teyoke is the change of the pole temperature relative to the initial temperature value Teyoke in the test time period T, and due to the fact that the magnetic yoke temperature is an indirect measurement quantity relative to the magnetic field, proper k2 needs to be selected according to the magnetic yoke material and the influence effect.
The second step comprises the following processes:
1) the measured data acquisition communication equipment carries out stability test within the selected time T, and after the accelerator reaches stable operation at the test starting time TS, the sensitivity S4 of the influence factor of the measured data acquisition communication equipment is delta Bmea/Bmea;
2) ensuring that Si satisfies | Si | < P within the test time T, and
under the condition of (1), the stability test of the magnetic field motion system is carried out under the condition of ensuring the stable operation of the accelerator and the stable measurement equipment, and P is the magnetic field measurement precision.
The third step comprises the following processes:
1) the stability test is carried out on the measuring movement positioning device within the selected time T, and then the sensitivity of the influence factors of the magnetic field movement system is tested
Wherein Δ brachius is the change in the arithmetic mean number Bradius from the radial magnetic field measurements during the test period at the same radius after a fixed angle θ has moved radially several times relative to the magnetic field during the test period, and Δ Bangel is the change in the arithmetic mean number Bangel from the angular magnetic field measurements during the test period at the same angle after an angle R has moved angularly several times relative to the magnetic field during the test period at the fixed radius;
m1 is the number of test points taken by the radial test; m2 is the number of test points taken by the radial test; k3 and k4 carry out weight distribution according to the radial motion and angular motion proportion during actual magnetic field measurement;
the determination of k3 and k4 is selected according to radial positioning accuracy Pradius (unit meter) and angular positioning accuracy Pangel (unit degree), and weights k3 and k4 are distributed according to the proportion of Pradius and R × Pangel;
2) finally, P is less than or equal to Si according to the stability condition of magnetic field measurement, and
advantageous effects of the invention
The invention adopts a method of combining the limitation of the absolute value of the stability of the magnetic field of a single factor and the limitation of the absolute value of the stability of the magnetic field of a comprehensive factor, and the two methods are mutually supported and interdependent, so that the stability of a power supply system, a water cooling system for magnetic field measurement, the temperature and the humidity of the environment for magnetic field measurement, a communication system of magnetic field measurement equipment, a magnetic field measurement system and a magnetic field measurement motion positioning device is ensured, a magnetic field measurement result with higher precision is obtained, and the physical design requirement is met. The method solves the technical problem that the field is lack of research on the stability of magnetic field measurement for a long time and is not systematic enough, and has outstanding substantive characteristics and remarkable progress.
Drawings
FIG. 1 is a schematic view of an evaluation system used in the evaluation method of the present invention;
FIG. 2 is a top view of a magnetic field measurement system layout according to the present invention;
FIG. 3 is a front view of the magnetic field measurement system layout (magnetometer section) of the present invention;
1: a main magnet power supply; 2: a high-precision direct current sensor; 3: a water cooling unit; 4: a water flow sensor; 5: a main coil power supply interface; 6: a main coil water-cooling interface; 7: a magnetic yoke; 8: a main coil; 9: a magnetic pole; 10: a magnetic field measuring device; 11: a magnetic field measuring probe; 12: a thermistor; 13: a motion control module; 14: an industrial personal computer; 15: a gauss meter; 16: a control platform; 17: a humidity measuring instrument; 18: a shield case;
Detailed Description
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
Design principle of the invention
1. The design difficulty of the invention is as follows: one of the difficulties is to overcome the traditional prejudice and find out all the factors influencing the stability of the magnetic field which are not easy to be thought in the field. The magnetic field measurement stability is determined by various influence factors, the conventional test magnetic field stability only comprises three factors of water, electricity and ambient temperature, the influence of the accuracy of the data acquisition communication equipment and the motion positioning device on the measurement of the magnetic field stability is ignored, and the data acquisition communication equipment and the motion positioning device are not problematic by default. However, in fact, these two types of factors can also have an effect: the reading of the magnetic field measuring probe (generally a Hall probe) can drift along with the time, and if the drift amount is not within the allowable error, the accuracy of the measuring result is difficult to ensure; the magnetic field measurement movement positioning device is required to ensure that the repeatability with certain precision is realized in the magnetic field measurement process, and the judgment of the magnetic field stability is also influenced if the measurement result of each time is different. The second difficulty lies in: a scientific evaluation method is adopted: for the magnetic field measurement data acquisition stability unit and the magnetic field measurement movement positioning device stability unit, except for the evaluation of each level of factors, the evaluation of comprehensive factors is combined, and the comprehensive factor evaluation is that all factors before the current factors are taken as comprehensive evaluation factors of the current factors; is expressed by the formula: i Si is less than or equal to P, and
2. the design principle of a magnetic field stability evaluation formula is as follows:
first, formula
Allowing positive and negative factors to be present and offset each other. For example, the power supply system, the water cooling system, the ambient temperature and humidity system and the data acquisition and communication system allow positive and negative to occur, but the value after the positive and negative are balanced should be less than or equal to the magnetic field measurement precision P, which is acceptable;
secondly, the positive and negative ranges of the magnetic field measurement stability evaluation value of each factor of the 5 factors of the power supply system, the water cooling system, the ambient temperature and humidity system, the data acquisition communication system and the motion positioning device are respectively limited by a formula | Si | ≦ P, if P is 10, the positive and negative absolute values of the factors cannot exceed 10, and if the limitation does not exist, only the formula is used
Based on the invention principle, the invention designs an evaluation system for measuring the magnetic field stability of the compact small-sized cyclotron.
An evaluation system for compact cyclotron magnetic field stability measurement: the system is shown in fig. 2 and comprises stability evaluation units (1,2 and 8) of a magnetic field measurement power supply system, stability evaluation units (3, 4, 8, 9 and 12) of a magnetic field measurement water cooling system, stability evaluation units (7,12 and 17) of magnetic field measurement environment temperature and humidity, stability evaluation units (11, 14, 15, 13, 16 and 18) of a magnetic field measurement data acquisition communication system and stability evaluation units (10,11 and 13) of a magnetic field measurement motion positioning device; the magnetic field measurement data acquisition communication system stability evaluation unit and the magnetic field measurement movement positioning device stability evaluation unit respectively comprise stability evaluation on self factors and stability evaluation on comprehensive factors; the stability evaluation units of the power supply system, the water cooling system and the environment temperature and humidity system provide stability evaluation of comprehensive factors for the stability evaluation unit of the data acquisition communication system; and the stability evaluation units of the power supply system, the water cooling system, the ambient temperature and humidity system and the data acquisition and communication system provide stability evaluation of comprehensive factors for the stability evaluation unit of the motion positioning device.
The power supply system stability evaluation unit comprises a cyclotron main magnet power supply system stability evaluation module and a controller power supply system stability evaluation module; the stability evaluation unit of the data acquisition communication system comprises a Hall probe stability evaluation module, a gaussmeter stability evaluation module, an optical fiber-to-serial port transponder stability evaluation module and a communication equipment stability evaluation module; the motion positioning device stability evaluation unit comprises a magnetic meter stability evaluation module, an encoder stability evaluation module and a circular grating stability evaluation module.
Supplementary explanation:
the power supply system comprises a main magnet power supply system of the cyclotron and a controller power supply system, the main magnet power supply system is connected with the main magnet coil of the accelerator to supply current for the main magnet coil of the accelerator, an induced magnetic field is generated at a magnetic pole, the stability of the main magnet power supply system is directly related to the magnetic field, and the current precision supplied by the main magnet power supply is ensured to be consistent with the precision required by magnetic field measurement in the magnetic field measurement process; the controller power supply system is a control system power supply, so that the normal work of the control system is ensured, the control system is generally a precise instrument, and the problem that the instrument is easily interfered by low power supply quality during peak power utilization period is avoided.
In the magnetic field measurement water cooling system, the water cooling system is connected with the main coil of the accelerator, the main coil is electrified to generate heat during the excitation of the accelerator, the water cooling system plays a role in cooling the main coil to ensure that the main coil normally works at a proper temperature, and the water flow of the water cooling system during the magnetic field measurement can meet the requirement of total heat dissipation power in the main coil. The stability of the water cooling system is an important means for ensuring the constant temperature inside the accelerator, and the excessive temperature difference inside the accelerator during the magnetic field measurement can cause the deformation of the magnetic poles to cause the change of the air gap between the magnetic poles, so that the error of the measurement result is larger.
The magnetic field measures the ambient temperature and humidity, and in the magnetic field measuring process, the ambient temperature and humidity in the operating environment of the small cyclotron can be greatly different due to different seasons or day and night, so that the ambient temperature and humidity can be kept in a proper range, and the magnetic field measuring method is an important premise for ensuring the stability of the magnetic field measurement. Environmental temperature humidity can produce the influence to exposing the yoke in external environment, and environmental temperature humidity changes too greatly and can lead to the yoke to produce deformation, causes the magnetic field to change.
The magnetic field measurement data acquisition communication system consists of a magnetic field measurement probe and a gaussmeter, wherein the magnetic field measurement probe is used for acquiring accelerator magnetic field signals in real time, transmitting acquired analog signals to the gaussmeter, processing the signals by the gaussmeter, converting the signals into digital signals and outputting the digital signals to a magnetic field measurement equipment communication system for display and storage. During the magnetic field measurement, the reading drift of the magnetic field measurement probe (generally, a hall probe) is ensured to be within an allowable error so as to ensure the accuracy of the measurement result; the data acquisition and communication system also comprises a magnetic field measurement device communication system, wherein the magnetic field measurement device communication system has the functions of acquiring, processing and storing magnetic field measurement data, sending a motion logic command to the magnetic field measurement device, receiving feedback of the measurement device and the like, and the communication system and the magnetic field measurement device perform real-time interaction in the magnetic field measurement process so as to complete the whole magnetic field measurement program. The stability of the communication system of the magnetic field measuring equipment is ensured, the interferences of the leakage magnetic field of an accelerator, the vibration generated when a magnetic field measuring device moves and the like are avoided, and the problems of communication logic transmission errors or data reading errors and the like are prevented.
The magnetic field measurement movement positioning device is used for carrying a magnetic field measurement probe, so that the magnetic field measurement system can complete radial and circumferential movement in the accelerator, the magnetic field measurement probe can move to cover the whole magnetic field measurement plane, and complete magnetic field measurement data can be acquired. The magnetic field measurement movement positioning device is required to ensure that the repeatability with certain precision is realized in the magnetic field measurement process, and the multiple measurement results have reference value.
Based on the measurement system, the invention designs an evaluation method for measuring the magnetic field stability of the compact small-sized cyclotron
An evaluation method for measuring the magnetic field stability of a compact small-sized cyclotron comprises the following steps:
measuring the influence of an operating environment on the magnetic field stability of the compact cyclotron;
measuring the influence of data acquisition communication equipment on the magnetic field stability of the compact cyclotron;
thirdly, measuring the magnetic field stability of the compact cyclotron by the measuring motion positioning device;
the operation environment comprises a magnetic field measurement power supply system, a magnetic field measurement water cooling system and a magnetic field measurement environment temperature and humidity; the data acquisition communication equipment comprises a Hall probe, a gaussmeter, an optical fiber-to-serial port converter and magnetic field measurement communication equipment; the motion positioning device comprises a magnetism measuring instrument, an encoder and a circular grating;
the method is characterized in that: the stability test of the data acquisition communication equipment is carried out under the condition of ensuring the stable operation environment of the compact type small-sized cyclotron; the stability test of the magnetic field motion system is carried out under the condition of ensuring the stable operation environment of the compact type small-sized cyclotron and the stable data acquisition communication equipment;
the first step comprises the following processes:
1) measuring the influence of power supply stability on the magnetic field stability of a compact cyclotron
The power supply is tested for 24 hours, the testing time comprises power utilization peaks and valleys, the time T is taken to be greater than the actual magnetic field measuring time T0 after the testing is finished, and according to a B-I curve of a magnetic field, the power supply influence factor sensitivity S1 is B (delta I)/B (I), wherein delta I is the change of current relative to a set value I in the testing time period T;
2) measuring the influence of the stability of a water cooling system on the stability of the magnetic field of a compact cyclotron
Collecting magnetic pole temperature through a thermistor, synchronously carrying out temperature collection and power supply test in 1, and taking time T to be greater than actual magnetic field measurement time T0, wherein magnetic pole temperature influence factor sensitivity S2 is k1 delta Tepole/Tepole, wherein delta Tepole is the change of the magnetic pole temperature relative to an initial temperature value Tepole in a test time period T, and proper k1 needs to be selected according to magnetic pole materials and influence effects because the magnetic pole temperature is an indirect measurement quantity relative to a magnetic field;
3) measuring the effect of ambient temperature stability on magnetic field stability for compact cyclotrons
The temperature of the magnetic yoke is collected through a thermistor, the temperature collection is carried out synchronously with the power supply test in the step 1, the time T is greater than the actual magnetic field measurement time T0, the magnetic yoke temperature influence factor sensitivity S3 is k2 delta Teyoke/Teyoke, wherein delta Teyoke is the change of the pole temperature relative to the initial temperature value Teyoke in the test time period T, and due to the fact that the magnetic yoke temperature is an indirect measurement quantity relative to the magnetic field, proper k2 needs to be selected according to the magnetic yoke material and the influence effect.
The second step comprises the following processes:
1) the measured data acquisition communication equipment carries out stability test within the selected time T, and after the accelerator reaches stable operation at the test starting time TS, the sensitivity S4 of the influence factor of the measured data acquisition communication equipment is delta Bmea/Bmea;
2) ensuring that Si satisfies | Si | < P within the test time T, and
under the condition of (1), the magnetic field motion system is carried out under the condition of ensuring the stable operation of the accelerator and the stable measurement equipmentAnd (5) testing stability, wherein P is magnetic field measurement precision.
The third step comprises the following processes:
1) the stability test is carried out on the measuring movement positioning device within the selected time T, and then the sensitivity of the influence factors of the magnetic field movement system is tested
Wherein Δ brachius is the change in the arithmetic mean number Bradius from the radial magnetic field measurements during the test period at the same radius after a fixed angle θ has moved radially several times relative to the magnetic field during the test period, and Δ Bangel is the change in the arithmetic mean number Bangel from the angular magnetic field measurements during the test period at the same angle after an angle R has moved angularly several times relative to the magnetic field during the test period at the fixed radius;
m1 is the number of test points taken by the radial test; m2 is the number of test points taken by the radial test; k3 and k4 carry out weight distribution according to the radial motion and angular motion proportion during actual magnetic field measurement;
the determination of k3 and k4 is selected according to radial positioning accuracy Pradius (unit meter) and angular positioning accuracy Pangel (unit degree), and weights k3 and k4 are distributed according to the proportion of Pradius and R × Pangel;
2) finally, P is less than or equal to Si according to the stability condition of magnetic field measurement, and
example one
As shown in fig. 1, the evaluation method for magnetic field measurement stability of a compact small-sized cyclotron provided by the present invention includes power supply system stability evaluation 1,2, magnetic field measurement water cooling system stability 3, 4, 8, 9, magnetic field measurement environment temperature and humidity stability 7, 17, magnetic field measurement device communication system stability 13, 14, 15, magnetic field measurement system stability 11, 15, and magnetic field measurement motion positioning device stability 13, 18.
Firstly, evaluating the stability of a power supply system, wherein a power supply 1 is connected with a power supply interface 5 of a main coil 8 through a high-precision direct current sensor 2, the testing time T is longer than the actual magnetic field measuring time T0, and whether the fluctuation range of the current reading value of the high-precision direct current sensor 2 can meet the magnetic field measuring precision or not is observed during the testing period so as to evaluate the stability of the power supply system.
Secondly, evaluating the stability of the magnetic field measurement water cooling system, connecting the water cooling unit 3 with a water cooling interface of the main coil 8 through the water flow sensor 4, starting the power supply 1 after starting the water machine, wherein the test time T is greater than the actual magnetic field measurement time T0, observing the water flow reading value of the water flow sensor 4, observing whether the temperature value returned by the thermistor 12 positioned at the main coil 8 and the magnetic pole 9 has larger fluctuation during the test period after reaching the stability, and increasing or reducing the water cooling unit water flow according to the returned temperature value until the temperature value returned by the thermistor 12 meets the requirement in the fluctuation range during the test period, and evaluating the stability of the magnetic field measurement water cooling system by the above method.
Thirdly, the stability of the ambient temperature and humidity is evaluated in magnetic field measurement, the ambient temperature is mainly monitored through the thermistor 12 located at the magnetic yoke 7, meanwhile, the ambient humidity is monitored through the humidity measuring instrument 17, the testing time T is larger than the actual magnetic field measuring time T0, the readings of the thermistor 12 located at the magnetic yoke 7 and the reading of the humidity measuring instrument 17 are guaranteed to be kept within a reasonable range in the testing time, and if abnormity occurs, the stability of the ambient temperature and humidity in magnetic field measurement is evaluated through auxiliary equipment.
Fourthly, the stability evaluation of the magnetic field measurement data acquisition communication system, the magnetic field measurement probe 11 is placed at a fixed position in an accelerator, a gaussmeter 15 reads magnetic field values and transmits the magnetic field values to an industrial personal computer 14 through a communication cable for recording, under the condition that the accelerator is ensured to operate stably, the test time T is greater than the actual magnetic field measurement time T0, whether the communication sending values and the return values of each device are abnormal or not is recorded during the test, measures such as magnetic shielding, electric shielding and decoupling are carried out on the communication cable at a position which is easy to be interfered, the drift amount generated by the magnetic field measurement reading is judged through the fixed point magnetic field values recorded during the test, whether the accuracy requirement during the magnetic field measurement period can be met or not is judged, and the stability of the magnetic field measurement data acquisition communication system is.
Fifthly, evaluating the stability of the magnetic field measurement movement positioning device, controlling the magnetic field measurement device 10 through a magnetic field measurement device movement control module 13 with a shield 18, placing the magnetic field measurement probe 11 at a fixed radius position, performing magnetic field measurement of 0-360-degree and 360-720-degree movement, and comparing whether the magnetic field value of a corresponding point can meet the measurement precision requirement after two-week measurement; and then the magnetic field measuring probe 11 is arranged at a fixed angle position, forward and backward magnetic field measurement of the same radial path is carried out, whether the magnetic field values of corresponding points in the forward and backward processes can meet the requirement of measurement accuracy is compared, and the stability of the magnetic field measuring motion positioning device is evaluated by combining the above.
The method for evaluating the magnetic field measurement stability of the compact small-sized cyclotron is not limited to the above specific embodiment, and those skilled in the art can derive other embodiments according to the technical solution of the present invention, which also belongs to the technical innovation scope of the present invention.
Claims (6)
1. An evaluation system for magnetic field stability measurement of a compact cyclotron comprises a magnetic field measurement power supply system stability evaluation unit, a magnetic field measurement water cooling system stability evaluation unit, a magnetic field measurement environment temperature and humidity stability evaluation unit, a magnetic field measurement data acquisition communication system stability evaluation unit and a magnetic field measurement motion positioning device stability evaluation unit; the method is characterized in that:
the magnetic field measurement data acquisition communication system stability evaluation unit and the magnetic field measurement movement positioning device stability evaluation unit respectively comprise stability evaluation on self factors and stability evaluation on comprehensive factors; stability evaluation units of the power supply system, the water cooling system and the environment temperature and humidity system provide stability evaluation of comprehensive factors for a data acquisition communication system stability evaluation unit; and the stability evaluation units of the power supply system, the water cooling system, the ambient temperature and humidity system and the data acquisition and communication system provide stability evaluation of comprehensive factors for the stability evaluation unit of the motion positioning device.
2. An evaluation system for compact cyclotron magnetic field stability measurement as claimed in claim 1, wherein: the power supply system stability evaluation unit comprises a cyclotron main magnet power supply system stability evaluation module and a controller power supply system stability evaluation module; the stability evaluation unit of the data acquisition communication system comprises a Hall probe stability evaluation module, a gaussmeter stability evaluation module, an optical fiber-to-serial port transponder stability evaluation module and a communication equipment stability evaluation module; the motion positioning device stability evaluation unit comprises a magnetic meter stability evaluation module, an encoder stability evaluation module and a circular grating stability evaluation module.
3. The evaluation method of an evaluation system for compact cyclotron magnetic field stability measurement according to claim 1, characterized in that: the method comprises the following steps:
measuring the influence of an operating environment on the magnetic field stability of the compact cyclotron;
measuring the influence of data acquisition communication equipment on the magnetic field stability of the compact cyclotron;
thirdly, measuring the magnetic field stability of the compact cyclotron by the measuring motion positioning device;
the operation environment comprises a magnetic field measurement power supply system, a magnetic field measurement water cooling system, a magnetic field measurement environment temperature and humidity, and the data acquisition communication equipment comprises a Hall probe, a gaussmeter, an optical fiber-to-serial port transponder and magnetic field measurement communication equipment; the motion positioning device comprises a magnetism measuring instrument, an encoder and a circular grating;
the method is characterized in that: the stability test of the data acquisition communication equipment is carried out under the condition of ensuring the stable operation environment of the compact cyclotron; and the stability test of the magnetic field motion system is carried out under the condition of ensuring the stability of the operation environment of the compact cyclotron and the stability of the data acquisition communication equipment.
4. An evaluation method for compact cyclotron magnetic field stability measurement according to claim 3, characterized in that: the first step comprises the following processes:
1) measuring the influence of power supply stability on the magnetic field stability of a compact cyclotron
The power supply is tested for 24 hours, the testing time comprises power utilization peaks and valleys, the time T is taken to be greater than the actual magnetic field measuring time T0 after the testing is finished, and according to a B-I curve of a magnetic field, the power supply influence factor sensitivity S1 is B (delta I)/B (I), wherein delta I is the change of current relative to a set value I in the testing time period T;
2) measuring the influence of the stability of a water cooling system on the stability of the magnetic field of a compact cyclotron
Collecting magnetic pole temperature through a thermistor, synchronously carrying out temperature collection and power supply test in 1, and taking time T to be greater than actual magnetic field measurement time T0, wherein magnetic pole temperature influence factor sensitivity S2 is k1 delta Tepole/Tepole, wherein delta Tepole is the change of the magnetic pole temperature relative to an initial temperature value Tepole in a test time period T, and proper k1 needs to be selected according to magnetic pole materials and influence effects because the magnetic pole temperature is an indirect measurement quantity relative to a magnetic field;
3) measuring the effect of ambient temperature stability on magnetic field stability for compact cyclotrons
The temperature of the magnetic yoke is collected through a thermistor, the temperature collection is carried out synchronously with the power supply test in the step 1, the time T is greater than the actual magnetic field measurement time T0, the magnetic yoke temperature influence factor sensitivity S3 is k2 delta Teyoke/Teyoke, wherein delta Teyoke is the change of the pole temperature relative to the initial temperature value Teyoke in the test time period T, and due to the fact that the magnetic yoke temperature is an indirect measurement quantity relative to the magnetic field, proper k2 needs to be selected according to the magnetic yoke material and the influence effect.
5. An evaluation method for compact cyclotron magnetic field stability measurement according to claim 3, characterized in that: the second step comprises the following processes:
1) the measured data acquisition communication equipment carries out stability test within the selected time T, and after the accelerator reaches stable operation at the test starting time TS, the sensitivity S4 of the influence factor of the measured data acquisition communication equipment is delta Bmea/Bmea;
wherein TS is the test starting time, TE test ending time, TE-TS is T, and B is the magnetic field measurement value of the test time; the delta Bmea is Bmax-Bmin, wherein Bmax is the maximum value of the magnetic field in the test time, and Bmin is the minimum value of the magnetic field in the test time;
2) ensuring that Si satisfies | Si | < P within the test time T, and
under the condition of (1), the stability test of the magnetic field motion system is carried out under the condition of ensuring the stable operation of the accelerator and the stable measurement equipment, and P is the magnetic field measurement precision.
6. The evaluation method for magnetic field stability of a compact cyclotron according to claim 3, wherein: the third step comprises the following processes:
1) the stability test is carried out on the measuring movement positioning device within the selected time T, and then the sensitivity of the influence factors of the magnetic field movement system is tested
Wherein Δ brachius is the change in the arithmetic mean number Bradius from the radial magnetic field measurements during the test period at the same radius after a fixed angle θ has moved radially several times relative to the magnetic field during the test period, and Δ Bangel is the change in the arithmetic mean number Bangel from the angular magnetic field measurements during the test period at the same angle after an angle R has moved angularly several times relative to the magnetic field during the test period at the fixed radius;
m1 is the number of test points taken by the radial test; m2 is the number of test points taken by the radial test; k3 and k4 carry out weight distribution according to the radial motion and angular motion proportion during actual magnetic field measurement;
the determination of k3 and k4 is selected according to radial positioning accuracy Pradius (unit meter) and angular positioning accuracy Pangel (unit degree), and weights k3 and k4 are distributed according to the proportion of Pradius and R × Pangel;
2) finally, P is less than or equal to Si according to the stability condition of magnetic field measurement, and
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114047463A (en) * | 2021-08-25 | 2022-02-15 | 中国兵器工业第五九研究所 | Dynamic magnetic field multi-factor composite environment simulation device and method |
| CN116466271A (en) * | 2023-04-18 | 2023-07-21 | 中国科学院近代物理研究所 | Full-automatic spot measurement system and method for accelerator magnet magnetic field distribution measurement |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104219865A (en) * | 2014-09-09 | 2014-12-17 | 中国原子能科学研究院 | Circulating water cooling system of cyclotron and high stability implementing method of circulating water cooling system |
| KR101751594B1 (en) * | 2015-06-24 | 2017-07-03 | 조선대학교산학협력단 | Control method for cyclotron and recording medium storing program for executing method of the same in computer |
| CN107340484A (en) * | 2017-07-12 | 2017-11-10 | 合肥中科离子医学技术装备有限公司 | Measuring magnetic field of cyclotron system and its measuring method based on search coil |
| CN108120888A (en) * | 2017-12-13 | 2018-06-05 | 合肥中科离子医学技术装备有限公司 | New cyclotron range stability measuring system |
| CN106231777B (en) * | 2016-07-29 | 2019-01-29 | 中国原子能科学研究院 | A kind of signal source of high stability of superconducting cyclotron |
| CN110677976A (en) * | 2019-11-16 | 2020-01-10 | 中国原子能科学研究院 | Cavity structure for picking up beam phase signals based on inductance probe |
-
2020
- 2020-10-14 CN CN202011096393.2A patent/CN112240993B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104219865A (en) * | 2014-09-09 | 2014-12-17 | 中国原子能科学研究院 | Circulating water cooling system of cyclotron and high stability implementing method of circulating water cooling system |
| KR101751594B1 (en) * | 2015-06-24 | 2017-07-03 | 조선대학교산학협력단 | Control method for cyclotron and recording medium storing program for executing method of the same in computer |
| CN106231777B (en) * | 2016-07-29 | 2019-01-29 | 中国原子能科学研究院 | A kind of signal source of high stability of superconducting cyclotron |
| CN107340484A (en) * | 2017-07-12 | 2017-11-10 | 合肥中科离子医学技术装备有限公司 | Measuring magnetic field of cyclotron system and its measuring method based on search coil |
| CN108120888A (en) * | 2017-12-13 | 2018-06-05 | 合肥中科离子医学技术装备有限公司 | New cyclotron range stability measuring system |
| CN110677976A (en) * | 2019-11-16 | 2020-01-10 | 中国原子能科学研究院 | Cavity structure for picking up beam phase signals based on inductance probe |
Non-Patent Citations (2)
| Title |
|---|
| 贾先禄等: "100MeV回旋加速器中心区实验台架上离子源磁铁布局设计", 《中国原子能科学研究院年报》 * |
| 钟俊晴等: "强流回旋加速器综合试验装置的磁场测量与垫补", 《CHINESE PHYSICS C(HEP&NP)》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114047463A (en) * | 2021-08-25 | 2022-02-15 | 中国兵器工业第五九研究所 | Dynamic magnetic field multi-factor composite environment simulation device and method |
| CN116466271A (en) * | 2023-04-18 | 2023-07-21 | 中国科学院近代物理研究所 | Full-automatic spot measurement system and method for accelerator magnet magnetic field distribution measurement |
| CN116466271B (en) * | 2023-04-18 | 2024-03-01 | 中国科学院近代物理研究所 | Full-automatic spot measurement system and method for accelerator magnet magnetic field distribution measurement |
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