Compensation differential integrator for magnetic confinement fusion device and use method

Abstract

The invention discloses a compensation differential integrator for a magnetic confinement fusion device and a use method, and relates to the technical field of magnetic confinement fusion, the compensation differential integrator comprises a resistor R1, a resistor R3, an adjustable resistor R2, a capacitor C1 and a first arithmetic unit, the resistor R1 and the adjustable resistor R2 are connected in series, one end of the resistor R1 and the adjustable resistor R2 after series connection forms an outer ring access end, and one end of the resistor R3 forms an inner ring access end; one end of the capacitor C1, the other end of the resistor R3 and the other end of the resistor R1 connected with the adjustable resistor R2 in series are all connected with the input end of the first arithmetic unit, and the other end of the capacitor C1 is connected with the output end of the first arithmetic unit to jointly form the output end of the compensation differential integrator; based on a diamagnetic measurement mode of concentric coils, a circuit is improved on the basis of a common differential integrator, and errors caused by an amplifier and the like are avoided on the basis that the area difference of the two coils does not need to be measured, so that the error influence caused by a traditional integrator is avoided.

Description

Technical Field

[0001] The present invention relates to the field of magnetic confinement fusion technology, and more specifically, to a compensating differential integrator for a magnetic confinement fusion device and a use method thereof. Background Art

[0002] In the field of magnetic confinement fusion, the ions (positive charge) and electrons (negative charge) in the plasma perform Larmor cyclotron motion around the magnetic lines of force under the toroidal magnetic field. The cyclotron of these ions and electrons produces a magnetic moment in the opposite direction of the "toroidal magnetic field", and all ions and electrons show a reverse magnetic effect on a macro scale. The more particles there are and the more intense the particle movement (the greater the thermal velocity), the greater the reverse magnetic flux. Therefore, by measuring the reverse magnetic flux, we can obtain important information such as the thermal energy stored in the plasma (abbreviated as: energy storage) and the confinement performance (specific pressure β).

[0003] The reverse magnetic flux is often only 10% of the toroidal magnetic field. -4 or 10 -3 For example, if the annular flux is 1Wb, the reverse magnetic flux is only 1mWb or even smaller. In order to measure the reverse magnetic flux, a certain polar section of the annular flux is usually measured (see Figure 1 A "reverse magnetic probe ring" is arranged on the plasma cross-sectional surface to measure the magnetic flux passing through, which includes annular magnetic flux and reverse magnetic flux, such as Figure 1 As shown, it is necessary to find a special method to deduct the signal (circular flux) that is several orders of magnitude larger and accurately obtain the small signal (reverse magnetic flux); the current method is through the schematic diagram Figure 1 The reverse magnetic flux can be calculated from the induced voltage at both ends of the reverse magnetic probe coil, the total magnetic flux passing through, the annular magnetic flux and the stray magnetic field of other magnetic fields.

[0004] There are several methods for reverse magnetic measurement, single turn loop plus compensation coil (such as Figure 2 As shown), and concentric coils (as Figure 3 As shown in the figure, there are two commonly used methods; among them, the single-turn loop plus compensation coil method requires the use of an amplifier, which will bring additional errors, while the concentric coil method requires knowing the area difference between the inner and outer coils in the concentric coil.

[0005] In view of this, this application is hereby made. Summary of the invention

[0006] The purpose of the present invention is to provide a compensated differential integrator for a magnetic confinement fusion device and a method of use. Based on the reverse magnetic measurement method of concentric coils, the circuit is improved on the basis of the commonly used differential integrator. Without the need to measure the area difference between the two coils, the error caused by amplifiers is avoided, thereby avoiding the error influence caused by traditional integrators.

[0007] The above technical objectives of the present invention are achieved through the following technical solutions:

[0008] In a first aspect, the present application provides a compensation differential integrator for a magnetic confinement fusion device, wherein the input end of the compensation differential integrator is connected to a concentric coil, the compensation differential integrator comprises a resistor R1, a resistor R3, an adjustable resistor R2, a capacitor C1 and a first operator, and the resistance values ​​of the resistor R1 and the resistor R3 are the same, wherein:

[0009] The resistor R1 is connected in series with the adjustable resistor R2, and one end of the series connection forms an outer loop access end connected to the outer loop coil in the concentric circle coil, and one end of the resistor R3 forms an inner loop access end connected to the inner loop coil in the concentric circle coil; one end of the capacitor C1, the other end of the resistor R3 and the other end of the series connection of the resistor R1 and the adjustable resistor R2 are all connected to the input end of the first operator, the other end of the capacitor C1 is connected to the output end of the first operator, and together form the output end of the compensated differential integrator; the input end of the compensated differential integrator includes an outer loop access end and an inner loop access end.

[0010] The beneficial effect of the present invention is as follows: in the present solution, the compensation differential integrator composed of the resistor R1, the resistor R3, the adjustable resistor R2, the capacitor C1 and the first operator is used. First, the concentric coil connected to the compensation differential integrator is placed in a toroidal field without adding plasma, and the output of the compensation differential integrator is made zero by the adjustable resistor R2, and the resistance value of the adjustable resistor R2 is obtained by measurement, and then plasma is added to the toroidal field. Since the parameters of the resistor R1, the resistor R3, the adjustable resistor R2 and the capacitor C1 are known, the reverse magnetic flux of the plasma can be calculated according to the output of the compensation differential integrator after adding plasma to the toroidal field.

[0011] In this scheme, there is no need to measure the area difference between the outer ring and the inner ring of the concentric coil. The resistance value of R2 of the differential integrator is adjusted to obtain the proportional relationship between the resistor R1, the resistor R3, and the adjustable resistor R2, and finally the reverse magnetic flux of the plasma is calculated according to the proportional relationship. The circuit is improved on the basis of the commonly used differential integrator, and an integrating bridge is adopted. The integrating circuit is simplified by using the bridge principle, which can avoid the influence of the traditional integrator and the error caused by the amplifier. Therefore, on the one hand, the error caused by the additional active device can be reduced, and on the other hand, there is no need to measure the coil area difference, which reduces the amount of calculation and improves the reverse magnetic measurement accuracy.

[0012] Based on the above technical solution, the present invention can also be improved as follows.

[0013] Furthermore, the above-mentioned compensated differential integrator also includes an analog compensation circuit and a digital compensation circuit, wherein:

[0014] The analog compensation circuit includes an adjustable resistor R4, a capacitor C2, a second operator and a third operator, one end of the adjustable resistor R4 is grounded, the other end of the adjustable resistor R4 is respectively connected to the input end of the second operator and one end of the capacitor C2, the other end of the capacitor C2, the output end of the second operator, the other end of the capacitor C1 and the output end of the first operator are all connected to the input end of the third operator, and the output end of the third operator forms the analog signal output end of the compensation differential integrator;

[0015] The digital compensation circuit includes a first analog-to-digital converter and a second analog-to-digital converter, the first analog-to-digital converter and the second analog-to-digital converter are respectively connected to the analog signal output end, and the first analog-to-digital converter is used to access the analog signal before the plasma pulse, and the second analog-to-digital converter is used to access the analog signal of the plasma pulse, and based on the output of the first analog-to-digital converter and the output of the second analog-to-digital converter, the digital signal corresponding to the analog signal output from the analog signal output end is compensated.

[0016] The beneficial effect of adopting the above further scheme is: since the output of the integrator will have a certain drift, drift compensation is required, and the drift compensation includes drift compensation for the output analog signal and drift compensation for the output digital signal; in the analog compensation circuit, the drift of the output analog signal is changed by adjusting the resistance value of the adjustable resistor R4, and when it meets the preset requirements, the drift compensation of the analog signal is completed. For example, the preset requirement can be within 1mv of drift every 15s; in the digital compensation circuit, the digital signal of the analog signal connected to the plasma pulse (plasma has been added) is compensated by the digital signal corresponding to the analog signal before the plasma pulse is connected (plasma has not been added), thereby realizing the drift compensation of the digital signal; in this way, the vacuum flux generated by the coil is reliably compensated, the accuracy is greatly improved, and the compensation of the analog signal realizes the increase of the amplitude of the output signal and the improvement of the signal-to-noise ratio.

[0017] Furthermore, the output of the output terminal of the above-mentioned compensation differential integrator is specifically:

[0018]

[0019] Where R1, R2, R3 and C represent the resistance of resistor R1, the resistance of adjustable resistor R2, the resistance of resistor R3 and the capacitance of capacitor C respectively. meas represents the flux signal output by the compensated differential integrator, It represents the circular magnetic flux measured by the outer ring coil in the concentric coil. Indicates the toroidal magnetic flux measured by the inner coil in the concentric coil, δΦ dia Indicates the reverse magnetic flux generated by the plasma to be tested.

[0020] Furthermore, the above-mentioned simplified integration circuit using the bridge principle, that is, using the input differential of the compensation differential integrator, the reverse magnetic flux is obtained by converting the output of the output end, specifically:

[0021]

[0022] Where R1, R2, R3 and C represent the resistance of resistor R1, the resistance of adjustable resistor R2, the resistance of resistor R3 and the capacitance of capacitor C respectively. meas Represents the flux signal output by the compensated differential integrator, δΦ dia Indicates the reverse magnetic flux generated by the plasma to be tested.

[0023] In a second aspect, the present application provides a method for using a compensating differential integrator for a magnetic confinement fusion device, which is applied to a compensating differential integrator for a magnetic confinement fusion device in any one of the first aspects, and comprises the following specific steps:

[0024] The inner loop access end and the outer loop access end of the compensation differential integrator are respectively connected to the inner loop coil and the outer loop coil of the concentric circle coil located in the toroidal field without adding plasma;

[0025] Adjust the resistance value of the adjustable resistor R2, and obtain the output of the output end of the compensation differential integrator during the process of adjusting the resistance value, until the output of the output end of the compensation differential integrator is zero, and detect and obtain the target resistance value of the adjustable resistor R2 when the output of the compensation differential integrator is zero;

[0026] The average toroidal magnetic fields of the areas surrounded by the inner and outer coils in the concentric coils are considered equal, and a target ratio is calculated based on the target resistance value;

[0027] The same concentric coil is placed in the toroidal field of the plasma to be measured, and the actual output of the compensation differential integrator is obtained. The reverse magnetic flux of the plasma to be measured is calculated using the actual output and the target ratio.

[0028] The beneficial effect of the present invention is as follows: in the present scheme, the compensation differential integrator composed of the resistor R1, the resistor R3, the adjustable resistor R2, the capacitor C1 and the first operator is used. First, the concentric coil connected to the compensation differential integrator is placed in a toroidal field without adding plasma, and the output of the compensation differential integrator is made zero by the adjustable resistor R2, and the resistance value of the adjustable resistor R2 is obtained by measurement, and then plasma is added to the toroidal field. Since the parameters of the resistor R1, the resistor R3, the adjustable resistor R2 and the capacitor C1 are known, the target ratio is calculated according to the various parameters, and finally the reverse magnetic flux of the plasma is calculated based on the target ratio and the output of the compensation differential integrator after adding plasma to the toroidal field.

[0029] Based on the above technical solution, the present invention can also be improved as follows.

[0030] Furthermore, the above target ratio is specifically:

[0031]

[0032] In the formula, represents the target ratio, R1 and R2 represent the resistance value of the resistor R1 and the resistance value of the adjustable resistor R2 respectively.

[0033] Furthermore, the actual output of the compensated differential integrator is obtained, and the reverse magnetic flux of the plasma to be measured is calculated using the actual output and the target ratio, specifically:

[0034]

[0035] In the formula, δΦ dia represents the reverse magnetic flux of the plasma to be measured, R3C represents the fixed parameters of the integration circuit in the compensation differential integrator, represents the target ratio, Φ meas1 It represents the actual output of the compensated differential integrator after adding the plasma to be measured.

[0036] Furthermore, when the output of the output terminal of the compensation differential integrator is zero, the target ratio is determined in the following manner:

[0037] in:

[0038] In the formula, It represents the circular magnetic flux measured by the outer ring coil in the concentric coil. It represents the annular magnetic flux measured by the inner coil in the concentric circle coil. R1, R2, and R3 represent the resistance value of resistor R1, the resistance value of adjustable resistor R2, and the resistance value of resistor R3 respectively. in and out They represent the average toroidal magnetic field in the area surrounded by the inner and outer coils of the concentric coils, respectively, and S in and S out They represent the areas of the inner and outer loops of the concentric coils respectively.

[0039] Furthermore, the above method also includes:

[0040] Under the circular cross-section configuration with a large ring diameter ratio, the poloidal specific pressure of the plasma to be measured is calculated based on the reverse magnetic flux of the plasma to be measured, specifically:

[0041]

[0042] In the formula, β p Indicates the polar specific pressure of the plasma to be measured, B T represents the toroidal magnetic field, μ0 represents the vacuum magnetic permeability, I P represents the current of the plasma to be measured, Φ dia Represents the reverse magnetic flux of the plasma to be measured.

[0043] Furthermore, the above method also includes:

[0044] In the circular cross-section configuration with a large ring diameter ratio, the energy storage of the plasma to be measured is calculated based on the reverse magnetic flux of the plasma to be measured, specifically:

[0045]

[0046] Where W dia represents the energy storage of the plasma to be measured, R represents the large radius, β p Indicates the polar specific pressure of the plasma to be measured, B T represents the toroidal magnetic field, μ0 represents the vacuum magnetic permeability, I P Indicates the current of the plasma to be measured.

[0047] In a third aspect, the present application provides the use of a compensated differential integrator as described in any one of the first aspects in measuring reverse magnetic flux of a plasma.

[0048] Compared with the prior art, the present invention has at least the following beneficial effects:

[0049] In the present application, a compensation differential integrator composed of a resistor R1, a resistor R3, an adjustable resistor R2, a capacitor C1 and a first operator is used. When in use, the concentric coil connected to the compensation differential integrator is first placed in a toroidal field without adding plasma, and the output of the compensation differential integrator is made zero through the adjustable resistor R2, and the resistance value of the adjustable resistor R2 is obtained by measurement, and then plasma is added to the toroidal field. Since the parameters of the resistor R1, the resistor R3, the adjustable resistor R2 and the capacitor C1 are known, the target ratio is calculated according to the various parameters, and finally the reverse magnetic flux of the plasma is calculated based on the target ratio and the output of the compensation differential integrator after adding plasma to the toroidal field.

[0050] In the present application, there is no need to measure the area difference between the outer ring and the inner ring of the concentric coil. The resistance value of R2 of the differential integrator is adjusted to obtain the proportional relationship between the resistor R1, the resistor R3, and the adjustable resistor R2, and finally the reverse magnetic flux of the plasma is calculated according to the proportional relationship; the circuit is improved on the basis of the commonly used differential integrator, and an integrating bridge is adopted. The integrating circuit is simplified by using the bridge principle, which can avoid the influence of the traditional integrator and the error caused by the amplifier, etc.; therefore, on the one hand, the error caused by the additional active device can be reduced, and on the other hand, there is no need to measure the coil area difference, which reduces the amount of calculation and improves the reverse magnetic measurement accuracy.

[0051] In the present application, since the output of the integrator will have a certain drift, drift compensation is required. Drift compensation includes drift compensation for the output analog signal and drift compensation for the output digital signal. In the analog compensation circuit, the drift of the output analog signal is changed by adjusting the resistance of the adjustable resistor R4. When the preset requirements are met, the drift compensation of the analog signal is completed. For example, the preset requirements may be within 1mv of drift every 15s. In the digital compensation circuit, the digital signal corresponding to the analog signal before the plasma pulse (plasma is not added) is connected to compensate for the digital signal of the analog signal connected to the plasma pulse (plasma is added), thereby realizing drift compensation of the digital signal. In this way, the vacuum flux generated by the coil is reliably compensated, the accuracy is greatly improved, and the compensation of the analog signal realizes the increase of the amplitude of the output signal and the improvement of the signal-to-noise ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0053] Figure 1 The figure is a schematic diagram of the generation of reverse magnetic flux and the arrangement of reverse magnetic exploration coil;

[0054] Figure 2 This is a schematic diagram of reverse magnetic measurement with a single-turn loop plus a compensation coil;

[0055] Figure 3 Schematic diagram of measuring reverse magnetic flux for concentric coils;

[0056] Figure 4 It is a schematic diagram of measuring reverse magnetic flux based on concentric coils and using a compensated differential integrator in an embodiment of the present invention;

[0057] Figure 5 Schematic diagram of a circuit in a compensated differential integrator in an embodiment of the present invention;

[0058] Figure 6 It is a curve diagram of the HL-2A vacuum magnetic field flux compensation in an embodiment of the present invention. DETAILED DESCRIPTION

[0059] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0060] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0062] In the description of the embodiments of the present invention, it should be noted that if the terms "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like appear to indicate directions or positional relationships, they are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. These are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0063] In the description of the embodiments of the present invention, "multiple" means at least 2.

[0064] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0065] Embodiment 1: This embodiment provides a compensation differential integrator for a magnetic confinement fusion device. The input end of the compensation differential integrator is connected to a concentric coil, such as Figure 4 As shown, the compensation differential integrator includes a resistor R1, a resistor R3, an adjustable resistor R2, a capacitor C1 and a first operator, and the resistance values ​​of the resistor R1 and the resistor R3 are the same, see Figure 4 , and in Figure 5 (a) is represented by Integrator A, where:

[0066] The resistor R1 is connected in series with the adjustable resistor R2, and one end of the series connection forms an outer loop access end connected to the outer loop coil in the concentric circle coil, and one end of the resistor R3 forms an inner loop access end connected to the inner loop coil in the concentric circle coil; one end of the capacitor C1, the other end of the resistor R3 and the other end of the series connection of the resistor R1 and the adjustable resistor R2 are all connected to the input end of the first operator, the other end of the capacitor C1 is connected to the output end of the first operator, and together form the output end of the compensated differential integrator; the input end of the compensated differential integrator includes an outer loop access end and an inner loop access end.

[0067] Optionally, the above-mentioned compensated differential integrator further includes an analog compensation circuit and a digital compensation circuit, such as Figure 5 As shown, where:

[0068] The analog compensation circuit includes an adjustable resistor R4, a capacitor C2, a second operator and a third operator. Figure 5 As shown in (a), and in Figure 5 In (a), it is represented as Integrator B, one end of the adjustable resistor R4 is grounded, the other end of the adjustable resistor R4 is respectively connected to the input end of the second operator and one end of the capacitor C2, the other end of the capacitor C2, the output end of the second operator, the other end of the capacitor C1 and the output end of the first operator are all connected to the input end of the third operator, and the output end of the third operator forms the analog signal output end of the compensated differential integrator.

[0069] Among them, since the output of the integrator will have a certain drift, drift compensation is required. Drift compensation includes drift compensation for the output analog signal and drift compensation for the output digital signal. In the analog compensation circuit, the drift of the output analog signal is changed by adjusting the resistance value of the adjustable resistor R4. When it meets the preset requirements, the drift compensation of the analog signal is completed. For example, the preset requirement can be that the drift is within 1mv every 15s.

[0070] Furthermore, the digital compensation circuit includes a first analog-to-digital converter and a second analog-to-digital converter, such as Figure 5 As shown in (b), the first analog-to-digital converter is Figure 5 (b) The upper ADC, the second ADC is Figure 5 (b) A / D converter in the middle and lower part; the first A / D converter and the second A / D converter are connected to the analog signal output terminal ( Figure 5 The first analog-to-digital converter is used to access the analog signal before the plasma pulse, and the second analog-to-digital converter is used to access the analog signal of the plasma pulse, and based on the output of the first analog-to-digital converter and the output of the second analog-to-digital converter, the digital signal corresponding to the analog signal outputted from the analog signal output terminal is compensated, Figure 5 Digital compensation in (b) represents the digital signal after compensation.

[0071] Among them, in the digital compensation circuit, that is, before the plasma pulse is connected (without adding plasma, Figure 5 Before plasma pulse) corresponds to the analog signal of the digital signal, which corresponds to the plasma pulse (plasma has been added, Figure 5 The digital signal of the analog signal (represented as plasma pulse) is compensated by the digital signal, thereby realizing the drift compensation of the digital signal; in this way, the accuracy is greatly improved by reliably compensating the vacuum flux generated by the coil, and the compensation of the analog signal realizes the increase of the amplitude of the output signal and the improvement of the signal-to-noise ratio.

[0072] Optionally, the output of the output terminal of the above-mentioned compensation differential integrator is specifically:

[0073] It can be converted into the following form:

[0074]

[0075] Where R1, R2, R3 and C represent the resistance of resistor R1, the resistance of adjustable resistor R2, the resistance of resistor R3 and the capacitance of capacitor C respectively. meas represents the flux signal output by the compensated differential integrator, It represents the circular magnetic flux measured by the outer ring coil in the concentric coil. Indicates the toroidal magnetic flux measured by the inner coil in the concentric coil, δΦ dia It represents the reverse magnetic flux generated by the plasma to be tested.

[0076] Optionally, the above-mentioned simplified integration circuit using the bridge principle, that is, using the input differential of the compensation differential integrator, the reverse magnetic flux is obtained by converting the output of the output end, specifically:

[0077] It can be converted into the following form:

[0078]

[0079] Where R1, R2, R3 and C represent the resistance of resistor R1, the resistance of adjustable resistor R2, the resistance of resistor R3 and the capacitance of capacitor C respectively. meas Represents the flux signal output by the compensated differential integrator, δΦ dia Indicates the reverse magnetic flux generated by the plasma to be tested.

[0080] Embodiment 2: The embodiment of the present application provides a method for using a compensating differential integrator for a magnetic confinement fusion device, which is applied to a compensating differential integrator for a magnetic confinement fusion device in any one of Embodiment 1, and includes the following specific steps:

[0081] S1, connecting the inner loop access end and the outer loop access end of the compensation differential integrator to the inner loop coil and the outer loop coil of the concentric circle coil located in the toroidal field without adding plasma.

[0082] Specifically, see Figure 4 , Figure 4 It can be seen as the schematic diagram of the concentric coil reverse magnetic measurement system and integration circuit on the HL-2A device; the concentric coil is composed of two polar single-turn ring coils located in the same polar section and surrounding the plasma, and the areas of the inner and outer single-turn rings are S in and S out , the area difference is ΔS=S out -S in ,like Figure 4 As shown, the output signals of the two coils are V out and V in , R2 is an adjustable resistor; then Figure 4 The output Φ at the output meas Specifically:

[0083]

[0084] Where R1, R2, R3 and C represent the resistance of resistor R1, the resistance of adjustable resistor R2, the resistance of resistor R3 and the capacitance of capacitor C respectively. meas represents the flux signal output by the compensated differential integrator, It represents the circular magnetic flux measured by the outer ring coil in the concentric coil. Indicates the toroidal magnetic flux measured by the inner coil in the concentric coil, δΦ dia Indicates the reverse magnetic flux generated by the plasma to be tested.

[0085] S2, adjust the resistance value of the adjustable resistor R2, and obtain the output of the output end of the compensation differential integrator in the process of adjusting the resistance value, until the output of the output end of the compensation differential integrator is zero, and detect and obtain the target resistance value of the adjustable resistor R2 when the output of the compensation differential integrator is zero.

[0086] Among them, in the discharge of a single toroidal field (without adding plasma), according to Figure 4 As shown, by adjusting the resistance of the adjustable resistor R2, the output Φ of the integrator circuit can be adjusted. meas When the output of the output terminal of the compensated differential integrator is zero, the target ratio is determined by the following method:

[0087] in:

[0088] In the formula, It represents the circular magnetic flux measured by the outer ring coil in the concentric coil. It represents the annular magnetic flux measured by the inner coil in the concentric circle coil. R1, R2, and R3 represent the resistance value of resistor R1, the resistance value of adjustable resistor R2, and the resistance value of resistor R3 respectively. in and out They represent the average toroidal magnetic field in the area surrounded by the inner and outer coils of the concentric coils, respectively, and S in and S out They represent the areas of the inner and outer loops of the concentric coils respectively.

[0089] S3, considering the average toroidal magnetic fields of the areas surrounded by the inner ring coil and the outer ring coil in the concentric circle coil to be equal, and calculating the target ratio based on the target resistance value.

[0090] If the distance between the two coils in the concentric coils is close enough, the average toroidal magnetic fields of the areas surrounded by the inner and outer coils in the concentric coils are considered equal, that is, in ≈ out , we can deduce:

[0091]

[0092] Optionally, the above target ratio is specifically:

[0093]

[0094] In the formula, represents the target ratio, R1 and R2 represent the resistance value of the resistor R1 and the resistance value of the adjustable resistor R2 respectively.

[0095] S4, placing the same concentric coil into the toroidal field of the plasma to be measured, and obtaining the actual output of the compensation differential integrator, and calculating the reverse magnetic flux of the plasma to be measured using the actual output and the target ratio.

[0096] Among them, in the case of plasma discharge, through Then the calculation formula of reverse magnetic flux can be deduced, and the reverse magnetic flux is expressed as:

[0097]

[0098] Also because R3C is a fixed parameter of the integration circuit, and the reverse magnetic flux can be expressed as:

[0099]

[0100] In the formula, R3 and C represent the resistance value of resistor R3 and the capacitance value of capacitor C1 respectively, Φ meas Represents the flux signal output by the compensated differential integrator, δΦ dia It represents the reverse magnetic flux generated by the plasma to be tested, represents the target ratio, and

[0101]

[0102] Specifically, when using the compensated differential integrator composed of resistor R1, resistor R3, adjustable resistor R2, capacitor C1 and the first operator, the concentric coil connected to the compensated differential integrator is first placed in a toroidal field without adding plasma, and the output of the compensated differential integrator is made zero through the adjustable resistor R2, and the resistance value of the adjustable resistor R2 is obtained by measurement, and then plasma is added to the toroidal field. Since the parameters of the resistor R1, resistor R3, adjustable resistor R2 and capacitor C1 are known, the target ratio is calculated according to the various parameters, and finally the reverse magnetic flux of the plasma is calculated based on the target ratio and the output of the compensated differential integrator after adding plasma to the toroidal field.

[0103] Specifically, to meet in ≈ out , then the area difference ΔS is required to be as small as possible. The integrator parameter R3C is closely related to the area difference. Under the premise of ensuring a certain signal-to-noise ratio (Φ meas Reaching the order of hundreds of millivolts), reducing the area difference means reducing the R3C value, which is usually selected to be around 0.5ms; the time constant RC of a conventional integrator is >10ms. As the time constant decreases, RC=0.1-1ms, the integral drift will become more and more serious. The average integral drift of a 0.5ms integrator is higher than several hundred millivolts per 10 seconds, >300mV / 10 seconds; therefore, the integrator needs to consider compensation drift, considering both analog compensation and digital compensation. The circuits corresponding to analog compensation and digital compensation are shown in Figure 5 , and the connection relationship and functions of the circuits corresponding to the analog compensation and digital compensation are introduced in Example 1, which will not be repeated here.

[0104] Optionally, the above method may further include: in a circular cross-section configuration with a large ring diameter ratio, based on the reverse magnetic flux of the plasma to be measured, calculating the poloidal specific pressure of the plasma to be measured, specifically:

[0105]

[0106] In the formula, β p Indicates the polar specific pressure of the plasma to be measured, B T represents the toroidal magnetic field, μ0 represents the vacuum magnetic permeability, I P represents the current of the plasma to be measured, Φ dia Represents the reverse magnetic flux of the plasma to be measured.

[0107] Optionally, the method may further include: calculating the energy storage of the plasma to be measured based on the reverse magnetic flux of the plasma to be measured under the circular cross-section configuration with a large ring diameter ratio, specifically:

[0108]

[0109] Where W dia represents the energy storage of the plasma to be measured, R represents the large radius, β p Indicates the polar specific pressure of the plasma to be measured, B T represents the toroidal magnetic field, μ0 represents the vacuum magnetic permeability, I P Indicates the current of the plasma to be measured.

[0110] Specifically, the following uses the HL-2A and HL-3 tokamak devices as examples. Taking the HL-2A device as an example, the distance δl between the two single-turn ring coils in the concentric coil is 2.5 cm, and the area difference ΔS / S out is 7%, and the integral time constant R3C is 0.5ms, as shown in Table 1. The resistor R3 in the analog compensation circuit needs to be subjected to a discharge test to determine a suitable value.

[0111] Table 1 Design parameters of the concentric circle reverse magnetic measurement system on the HL-2A device

[0112] δl <![CDATA[ΔS / S out ]]> <![CDATA[R1]]> C <![CDATA[δΦ dia ]]> <![CDATA[Φ meas ]]> 2.5cm ～7％ 5MΩ 0.1μF <![CDATA[~10-30×10 -4 Wb]]> ～0.1-0.4V

[0113] Specifically, Figure 6 The figure shows the curve diagram of the HL-2A vacuum magnetic field flux compensation in the embodiment of the present invention. Figure 6 (b) shows the output signals of three discharges, #18223 (R2 / R1=7.51%), #18224 (R2 / R1=7.47%) and #18225 (R2 / R1=7.52%). Then R1(R1+R2)C / R2=0.00715, R2 / (R1+R2)≈ΔS / S out = 6.99%, according to Figure 6 The cross-sectional area of ​​the HL-3 device is larger than that of the HL-2A device. The distance δl between the two single-turn loop coils is 1.8 cm, and the area difference ΔS / S out The integral time constant R3Cf is divided into four levels: 0.1ms, 0.5ms, 1ms, and 2ms, and can be changed according to the specific signal size.

[0114] Example 3: This embodiment of the present application provides the use of a compensated differential integrator as in any one of Example 1 in measuring the reverse magnetic flux of a plasma.

[0115] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A compensating differential integrator for a magnetic confinement fusion device, wherein the input end of the compensating differential integrator is connected to a concentric coil, characterized in that: The compensated differential integrator includes a resistor R1, a resistor R3, an adjustable resistor R2, a capacitor C1 and a first operator, and the resistance values ​​of the resistor R1 and the resistor R3 are the same, wherein: The resistor R1 is connected in series with the adjustable resistor R2, and one end of the series connection forms an outer loop access end connected to the outer loop coil in the concentric circle coil, and one end of the resistor R3 forms an inner loop access end connected to the inner loop coil in the concentric circle coil; one end of the capacitor C1, the other end of the resistor R3 and the other end of the series connection of the resistor R1 and the adjustable resistor R2 are all connected to the input end of the first operator, the other end of the capacitor C1 is connected to the output end of the first operator, and together form the output end of the compensated differential integrator; the input end of the compensated differential integrator includes an outer loop access end and an inner loop access end.

2. The compensating differential integrator for a magnetic confinement fusion device according to claim 1, characterized in that: The compensated differential integrator further includes an analog compensation circuit and a digital compensation circuit, wherein: The analog compensation circuit includes an adjustable resistor R4, a capacitor C2, a second operator and a third operator, one end of the adjustable resistor R4 is grounded, the other end of the adjustable resistor R4 is respectively connected to the input end of the second operator and one end of the capacitor C2, the other end of the capacitor C2, the output end of the second operator, the other end of the capacitor C1 and the output end of the first operator are all connected to the input end of the third operator, and the output end of the third operator forms the analog signal output end of the compensation differential integrator; The digital compensation circuit includes a first analog-to-digital converter and a second analog-to-digital converter, the first analog-to-digital converter and the second analog-to-digital converter are respectively connected to the analog signal output end, and the first analog-to-digital converter is used to access the analog signal before the plasma pulse, and the second analog-to-digital converter is used to access the analog signal of the plasma pulse, and based on the output of the first analog-to-digital converter and the output of the second analog-to-digital converter, the digital signal corresponding to the analog signal output from the analog signal output end is compensated.

3. The compensating differential integrator for a magnetic confinement fusion device according to claim 1, characterized in that: The output of the output terminal of the compensated differential integrator is specifically: Where R1, R2, R3 and C represent the resistance of resistor R1, the resistance of adjustable resistor R2, the resistance of resistor R3 and the capacitance of capacitor C respectively. meas represents the flux signal output by the compensated differential integrator, It represents the circular magnetic flux measured by the outer ring coil in the concentric coil. Indicates the toroidal magnetic flux measured by the inner coil in the concentric coil, δΦ dia Indicates the reverse magnetic flux generated by the plasma to be tested.

4. The compensating differential integrator for a magnetic confinement fusion device according to claim 3, characterized in that: The reverse magnetic flux is obtained by converting the output of the output end of the compensation differential integrator, specifically: Where R1, R2, R3 and C represent the resistance of resistor R1, the resistance of adjustable resistor R2, the resistance of resistor R3 and the capacitance of capacitor C respectively. meas Represents the flux signal output by the compensated differential integrator, δΦ dia It represents the reverse magnetic flux generated by the plasma to be tested.

5. A method for using a compensating differential integrator for a magnetic confinement fusion device, applied to a compensating differential integrator for a magnetic confinement fusion device as claimed in any one of claims 1 to 4, characterized in that: The specific steps include: The inner loop access end and the outer loop access end of the compensation differential integrator are respectively connected to the inner loop coil and the outer loop coil of the concentric circle coil located in the toroidal field without adding plasma; Adjust the resistance value of the adjustable resistor R2, and obtain the output of the output end of the compensation differential integrator during the process of adjusting the resistance value, until the output of the output end of the compensation differential integrator is zero, and detect and obtain the target resistance value of the adjustable resistor R2 when the output of the compensation differential integrator is zero; The average toroidal magnetic fields of the areas surrounded by the inner and outer coils in the concentric coils are considered equal, and a target ratio is calculated based on the target resistance value; The same concentric coil is placed in the toroidal field of the plasma to be measured, and the actual output of the compensation differential integrator is obtained. The reverse magnetic flux of the plasma to be measured is calculated using the actual output and the target ratio.

6. The method for using a compensating differential integrator for a magnetic confinement fusion device according to claim 5, characterized in that: The target ratio is specifically: In the formula, represents the target ratio, R1 and R2 represent the resistance value of the resistor R1 and the resistance value of the adjustable resistor R2 respectively.

7. The method for using a compensating differential integrator for a magnetic confinement fusion device according to claim 6, characterized in that: The actual output of the compensation differential integrator is obtained, and the reverse magnetic flux of the plasma to be measured is calculated using the actual output and the target ratio, specifically: In the formula, δΦ dia represents the reverse magnetic flux of the plasma to be measured, R3C represents the fixed parameters of the integration circuit in the compensation differential integrator, represents the target ratio, Φ meas1 It represents the actual output of the compensated differential integrator after adding the plasma to be measured.

8. The method for using a compensating differential integrator for a magnetic confinement fusion device according to claim 5, characterized in that: When the output at the output terminal of the compensated differential integrator is zero, the target ratio is determined by: In the formula, It represents the circular magnetic flux measured by the outer ring coil in the concentric coil. It represents the annular magnetic flux measured by the inner coil in the concentric circle coil. R1, R2, and R3 represent the resistance value of resistor R1, the resistance value of adjustable resistor R2, and the resistance value of resistor R3 respectively. in and out They represent the average toroidal magnetic field in the area surrounded by the inner and outer coils of the concentric coils, respectively, and S in and S out They represent the areas of the inner and outer loops of the concentric coils respectively.

9. The method for using a compensating differential integrator for a magnetic confinement fusion device according to claim 7, characterized in that: The method further comprises: In the circular cross-section configuration with a large ring diameter ratio, the poloidal specific pressure of the plasma to be measured is calculated based on the reverse magnetic flux of the plasma to be measured, specifically: In the formula, β p Indicates the polar specific pressure of the plasma to be measured, B T represents the toroidal magnetic field, μ0 represents the vacuum magnetic permeability, I P represents the current of the plasma to be measured, Φ dia Represents the reverse magnetic flux of the plasma to be measured.

10. The method for using a compensating differential integrator for a magnetic confinement fusion device according to claim 9, characterized in that: The method further comprises: In the circular cross-section configuration with a large ring diameter ratio, the energy storage of the plasma to be measured is calculated based on the reverse magnetic flux of the plasma to be measured, specifically: Where W dia represents the energy storage of the plasma to be measured, R represents the large radius, β p Indicates the polar specific pressure of the plasma to be measured, B T represents the toroidal magnetic field, μ0 represents the vacuum magnetic permeability, I P Indicates the current of the plasma to be measured.

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