阅读说明：本技术 能量可回收的脉冲强磁场产生装置和方法 (Energy-recoverable pulse strong magnetic field generating device and method ) 是由 彭涛 李亮 江山 王爽 于 2019-11-04 设计创作，主要内容包括：本发明公开了一种能量可回收的脉冲强磁场产生装置和方法,属于强磁场技术领域。该装置包括主放电回路、变压器放电回路、续流回路和充电回路；所述主放电回路包括串联连接的第一储能元件、第一开关、第一单向导通元件和磁体线圈；所述充电回路包括串联连接的第二储能元件、换能变压器原边线圈、第二开关和第二单向导通元件；所述变压器放电回路和所述续流回路并联在所述第一储能元件两端；所述变压器放电回路包括串联连接的换能变压器副边线圈和第三单向导通元件,所述续流回路包括串联连接的第三开关和第四单向导通元件。本发明通过换能变压器的耦合作用,实现了脉冲强磁场产生过程中的能量回收,具有减少磁体发热、能量重复利用的特点。(The invention discloses a pulse high-intensity magnetic field generating device and method capable of recycling energy, and belongs to the technical field of high-intensity magnetic fields. The device comprises a main discharging loop, a transformer discharging loop, a follow current loop and a charging loop; the main discharge loop comprises a first energy storage element, a first switch, a first one-way conduction element and a magnet coil which are connected in series; the charging loop comprises a second energy storage element, a primary coil of the transduction transformer, a second switch and a second one-way conduction element which are connected in series; the transformer discharging loop and the follow current loop are connected in parallel at two ends of the first energy storage element; the transformer discharging loop comprises a secondary side coil of the transduction transformer and a third one-way conduction element which are connected in series, and the follow current loop comprises a third switch and a fourth one-way conduction element which are connected in series. The invention realizes the energy recovery in the process of generating the pulse high-intensity magnetic field through the coupling action of the energy conversion transformer, and has the characteristics of reducing the heating of the magnet and recycling the energy.)

1. A pulse high-intensity magnetic field generating device with recoverable energy is characterized by comprising a main discharging loop, a transformer discharging loop, a follow current loop and a charging loop;

the main discharge circuit comprises a first energy storage element (C1), a first switch (S1), a first one-way conduction element (D1) and a magnet coil which are connected in series;

the charging loop comprises a second energy storage element (C2), a primary coil of the transduction transformer, a second switch (S2) and a second one-way conduction element (D2) which are connected in series;

the transformer discharging loop and the follow current loop are connected in parallel to two ends of the first energy storage element (C1); wherein the transformer discharge circuit comprises a secondary winding of the transduction transformer and a third unidirectional conductive element (D3) connected in series.

2. The apparatus of claim 1, wherein the freewheel circuit includes a third switch (S3) and a fourth one-way conducting element (D4) connected in series.

3. The apparatus according to claim 2, wherein said energy storage element is a capacitor.

4. The apparatus of claim 2, wherein said unidirectional conducting element is a diode.

5. The magnetic field generating method based on the pulsed high-intensity magnetic field generating device according to any one of claims 1 to 4, comprising the steps of:

charging a first energy storage element (C1) to a preset voltage value;

closing the first switch (S1) and the second switch (S2), starting discharging the first energy storage element (C1), and enabling a discharging current to flow back to the first energy storage element (C1) to reversely charge the first energy storage element (C1) after the discharging current flows through the magnet coil; after the first discharge is finished, the reverse discharge current of the first energy storage element (C1) passes through the transformer discharge loop to perform reverse discharge on the secondary coil of the transformer, and at the moment, a third switch (S3) of the follow current loop is switched on;

when the secondary side coil of the transformer is reversely discharged, the secondary side coil is coupled by the energy conversion transformer, an induced current is generated in the charging loop, and the second energy storage element (C2) is charged until the charging process is finished.

6. The magnetic field generation method of claim 4, wherein the preset voltage value is determined according to a desired strength of the pulsed magnetic field.

7. The magnetic field generating method of claim 5, applied to electromagnetic forming.

8. The magnetic field generating method according to claim 5, applied to the generation of a repetitive pulsed high-intensity magnetic field.

Technical Field

The invention belongs to the technical field of strong magnetic fields, and particularly relates to a pulse strong magnetic field generating device and method capable of recycling energy.

Background

The pulse strong magnetic field is one of the most effective tools in modern scientific experiments, and provides a lot of scientific opportunities for generating new technologies and proposing new concepts. The pulse high-intensity magnetic field is a magnetic field formed by instantly releasing large energy to a magnet coil to generate pulse current in space, so that different magnetic field waveforms can be obtained by adopting different treatment modes for energy in the process of generating the pulse high-intensity magnetic field, and further different influences can be generated on test results.

In electromagnetic forming application, the waveform of the magnetic field directly influences induced eddy current in a formed test piece, and the forming effect of a forming mode taking electromagnetic force formed by interaction of the induced eddy current in the test piece and a pulse strong magnetic field in space as driving force is directly influenced. At present, capacitors are used at home and abroad as power supplies to discharge to coils to obtain a pulse current waveform with a large change rate, and the current waveform is an attenuation oscillation waveform, as shown by a dotted line in fig. 1. However, the magnitude of the induced eddy current mainly depends on the rising phase of the pulse current, and the damping oscillation phase of the current rather enhances the rebound and wrinkling degree of the test piece. In Wuhan's national laboratory of high-intensity pulsed magnetic field, the follow current loop is added to the circuit to solve the above problem, but at the same time, the pulse width of the current waveform is increased, as shown by a dotted line in FIG. 1, the heating of the magnet coil is aggravated in the first oscillation period of the current, and the performance of the magnet is reduced.

Under the condition of not changing the waveform of the pulse magnetic field, the recovery and the reutilization of electromagnetic energy are key technologies for realizing the repetitive pulse strong magnetic field. The repetitive pulse high-intensity magnetic field is used as an extremely important experimental condition in modern scientific research and is widely applied to basic scientific research such as neutron diffraction, magnetization and the like. Energy feedback inductance is introduced into the power supply topological structure design in the national pulsed high-intensity magnetic field laboratory, and although energy recycling is realized and a 2Hz repeated pulsed high-intensity magnetic field is generated, the problems that the magnetic load inductance is limited by the energy feedback inductance and the magnetic field repetition frequency is limited by the charging power still exist. Therefore, the Wuhan national pulsed high-intensity magnetic field laboratory realizes the 50Hz high-frequency repeated pulsed high-intensity magnetic field by using a plurality of sets of power supply devices in parallel and adopting a mode of controlling a discharge time sequence, but the repeated pulse times are limited by the configuration number of the power supply devices, and the relative manufacturing cost is higher.

Generally, the conventional pulse high-intensity magnetic field generating device has the defects of single energy processing mode, large energy consumption, low utilization efficiency and poor economical efficiency. In different applications, different disadvantages also exist: in the electromagnetic forming technology, the phenomenon of rebounding and wrinkling of a test piece in the forming process is aggravated in the current waveform generated by the conventional device; in the technique of the repetitive pulse strong magnetic field, the number of repetitive pulses is limited by the configuration number of power supplies, and the construction cost is high.

The invention provides a pulse high-intensity magnetic field generating device and method capable of recycling energy, which can eliminate the oscillation stage of a current waveform under the condition of not changing the rising stage and the pulse width of the current waveform, and can improve the rebound and wrinkling phenomena of a test piece by applying an electromagnetic forming technology. Meanwhile, the device realizes energy recovery in the process of forming the pulse magnetic field waveform, and is expected to solve the technical problem that the number of repeated pulses is limited by the configuration number of power supply devices.

Disclosure of Invention

Aiming at the defects or improvement requirements of the prior art, the invention provides an energy-recoverable pulse high-intensity magnetic field generation device and method, aiming at solving the problem of energy recovery and utilization in the existing pulse high-intensity magnetic field, reducing energy loss and improving the waveform of the pulse magnetic field.

In order to achieve the aim, the invention provides an energy-recoverable pulse strong magnetic field generating device, which comprises a main discharging loop, a transformer discharging loop, a follow current loop and a charging loop, wherein the main discharging loop is connected with the transformer discharging loop;

the main discharge loop comprises a first energy storage element, a first switch, a first one-way conduction element and a magnet coil which are connected in series;

the charging loop comprises a second energy storage element, a primary coil of the transduction transformer, a second switch and a second one-way conduction element which are connected in series;

the transformer discharging loop and the follow current loop are connected in parallel at two ends of the first energy storage element; the transformer discharging loop comprises a secondary side coil of the transduction transformer and a third one-way conduction element which are connected in series, and the follow current loop comprises a third switch and a fourth one-way conduction element which are connected in series.

Further, the energy storage element is a capacitor, and the unidirectional conducting element is a diode.

The invention also provides a magnetic field generating method based on the pulse high-intensity magnetic field generating device, which comprises the following steps:

charging the first energy storage element to a preset voltage value;

the first switch and the second switch are closed, the first energy storage element starts to discharge, and the discharge current flows back to the first energy storage element to reversely charge the first energy storage element after flowing through the magnet coil; after the first discharge is finished, the reverse discharge current of the first energy storage element passes through the transformer discharge loop to perform reverse discharge on the secondary coil of the transformer, and at the moment, the third switch of the follow current loop is switched on;

when the secondary coil of the transformer is reversely discharged, an induced current is generated in the charging loop through the coupling action of the energy conversion transformer, and the second energy storage element is charged until the charging process is finished.

Further, the preset voltage value is determined according to the required pulse magnetic field intensity.

Further, the magnetic field generation method is applied to electromagnetic forming.

Further, the magnetic field generation method is applied to generation of a repetitive pulse strong magnetic field.

The invention adopts the energy conversion transformer to realize energy recovery under a pulse strong magnetic field, has the advantages of reducing loss, improving energy utilization rate and reducing heating of a magnet coil, and has unique advantages in a plurality of application occasions:

compared with other circuit structures, the invention has the advantages that the waveform of the magnet coil in the current rising stage is kept unchanged, the size of the induced eddy current is not influenced, meanwhile, the rebound and wrinkling conditions of a test piece are improved due to the absence of the current oscillation attenuation stage, the heat productivity of the magnet coil is reduced, and the performance of the magnet coil is ensured;

in the field of repeated pulse strong magnetic field, the invention adopts double power supplies to discharge a single magnet, thereby improving the problem that the repeated frequency of the magnetic field is limited by the charging time, simultaneously recovering energy, and the repeated pulse frequency is not limited by the configuration number of power supply devices.

Drawings

FIG. 1 is a schematic diagram comparing waveforms of different magnetic field devices in electromagnetic forming.

Fig. 2 is a schematic structural diagram of an energy-recoverable pulsed high-intensity magnetic field generating device according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Fig. 2 shows an energy-recoverable pulsed high-intensity magnetic field generating apparatus provided by an embodiment of the present invention, and for convenience of explanation, only the circuit part related to the present invention is shown.

The device comprises a main discharging loop, a transformer discharging loop, a follow current loop and a charging loop;

a first capacitor C1, a first switch S1, a first diode D1 and a magnet coil are sequentially connected in series in the main discharge loop, and the inductance and the internal resistance of the magnet coil are respectively marked as L and R1;

the charging loop comprises a second capacitor C2, a primary coil of the transduction transformer, a second switch S2 and a second diode D2 which are sequentially connected in series, and the charging loop is coupled with the main discharging loop through the transduction transformer;

the transformer discharging loop and the follow current loop are connected in parallel at two ends of the first capacitor C1; the transformer discharging loop comprises a secondary side coil of the transduction transformer and a third diode D3 which are sequentially connected in series, and the freewheeling loop comprises a third switch S3 and a fourth diode D4 which are sequentially connected in series.

The capacitor can be replaced by other energy storage elements for realizing the same function to be used as a power supply, and the diode can be replaced by other one-way conduction elements for realizing the same function.

In the embodiment of the invention, under the condition that the follow current circuit is disconnected, the first capacitor discharges the magnet coil through the main discharge circuit to generate a pulse magnetic field waveform, then the energy conversion transformer is discharged after the first capacitor is reversely charged, at the moment, the follow current circuit is conducted, and the transformer discharge circuit realizes the charging of the second capacitor through the energy conversion transformer to finish the process of energy recovery. The invention realizes energy recovery under a pulse high-intensity magnetic field through the coupling effect of the energy conversion transformer, and provides a new idea for electromagnetic forming and repeated pulse electromagnetic system design.

In an embodiment of the present invention, a magnetic field generating method based on the above energy-recoverable pulsed high-intensity magnetic field generating device includes the following steps:

a preparation stage: the first capacitor C1 is charged to a predetermined voltage level, which depends on the desired magnetic field strength.

And (3) a discharging stage: the first switch S1 and the second switch S2 are closed, the first capacitor C1 starts discharging, the current passes through the first switch S1, the first diode D1 and the magnet coil in sequence to generate a pulse magnetic field, and the discharging current returns to the first capacitor C1 after flowing through the magnet coil to reversely charge the first capacitor C1. After the first discharge is completed, the reverse discharge current of the first capacitor C1 passes through the transformer discharge circuit to reversely discharge the secondary coil of the transformer, and the reverse discharge current no longer passes through the magnet coil due to the action of the first diode D1, and at this time, the third switch S3 of the freewheeling circuit is turned on.

A charging stage: when the secondary coil of the transformer is reversely discharged, the induced current passes through the primary coil of the transduction transformer, the second diode D2 and the second switch S2 to charge the second capacitor C2 through the coupling effect of the transduction transformer until the charging process is finished, and the solid line waveform shown in fig. 1 is generated.

Fig. 1 shows a current waveform of a magnet coil in a conventional electromagnetic system, a current waveform of the magnet coil in the embodiment of the present invention, and a voltage waveform of a charging voltage after energy is recovered to a second capacitor C2, and it can be seen from the figure that, compared with the conventional electromagnetic system, there is no oscillation attenuation part for the current flowing through the magnet coil, and the pulse width of the current waveform is not significantly increased, so that the current waveform in the magnet coil can be changed to improve the phenomena of rebound and wrinkling of a test piece during the electromagnetic forming process in the conventional apparatus, and simultaneously, the heat generation of the magnet coil is reduced to prolong the service life of the magnet coil.

The invention realizes the recovery and the reutilization of energy, and can be applied to the optimization of a repetitive pulse generating device. In the implementation mode of the repetitive pulse high-intensity magnetic field proposed by the Wuhan national pulsed high-intensity magnetic field laboratory, the frequency of the generated repetitive pulses is high but the number of the repetitive pulses depends on the number of power supply devices, and one power supply device can only generate one single pulse waveform in one experiment, so that the problem of limited continuity of the high-frequency repetitive pulses exists. The energy-recoverable pulse high-intensity magnetic field device provided by the invention can realize energy recovery and utilization among different power supplies, and can recover energy by utilizing mutual coordination among different capacitors, so that the problem of waveform continuity in the device is hopefully solved, thereby improving the repetitive pulse frequency and breaking through the problem that the number of repetitive pulses is limited by the configuration number of power supplies.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.