Traveling wave resonant ring for aging high-power microwave device

Abstract

The invention discloses a traveling wave resonant ring for aging a high-power microwave device, and relates to the field of high-power microwave equipment, the traveling wave resonant ring comprises a coupler and a transmission line, the coupler comprises four ports, and the ports comprise a coupling port and an isolation port. Two ends of the transmission line are respectively connected to a coupling port and an isolation port of the coupler, and a tested unit is inserted in the middle of the transmission line to form a traveling wave resonant ring together with the coupler. According to the invention, low-power input is used, a high-power field is generated on the transmission line, and the field intensity gain of more than 15dB can be realized. The equipment can be used for aging high-power microwave equipment or devices, and the enhanced field intensity is dozens of times higher than the input field intensity, so that the aging of high-energy-consumption devices is realized with lower energy consumption.

Description

Technical Field

[0001] The invention relates to the field of high-power microwave equipment, in particular to a traveling wave resonant ring used for aging of high-power microwave devices. Background Art

[0002] High-power microwave devices have important applications in large scientific devices such as high-energy particle accelerators and controlled thermonuclear fusion superconducting tokamaks. High-energy particle accelerators (such as linear accelerators (LINAC)) use high-power microwaves to accelerate particles. The device has a very high acceleration gradient and is widely used in medical accelerator equipment. The microwave source frequency in a high-energy particle accelerator is usually matched with the resonant frequency of the acceleration cavity to achieve effective particle acceleration. The microwave frequencies commonly used in high-energy particle accelerators are generally between a few GHz and tens of GHz, and common frequencies include 2.5GHz, 3GHz, 5.7GHz, etc.; for superconducting acceleration cavities, the frequencies can be around 1.3GHz and 1.5GHz. The microwave power required for high-energy particle accelerators is in the order of tens of kilowatts to several megawatts. In superconducting tokamaks, low-harmonic heating (LHH), ion cyclotron resonance heating (ICRH) and electron cyclotron resonance heating (ECRH) are all commonly used and effective microwave heating methods. The output power of these heating methods is at least in the order of hundreds of kilowatts to megawatts, and requires long pulses or continuous wave operation. Among them, the typical frequency of low-harmonic heating (LHH) is in the range of hundreds of kHz to tens of MHz; the frequency of ion cyclotron resonance heating (ICRH) is usually between 20MHz and 100MHz; the frequency of electron cyclotron resonance heating (ECRH) is very high, usually between 75GHz and 300GHz.

[0003] Active or passive high-power microwave devices are widely used in high-energy particle accelerators and controlled thermonuclear fusion superconducting tokamaks. Since the high-power microwave devices used in these devices have the characteristics of high peak power and high average power, there are a large number of key components that withstand high-power microwaves in the devices and supporting components (typical components such as energy transmission windows, resonant cavities, waveguide components, etc.), so there is a large demand for aging and performance verification of these key components. However, since the aging and performance verification of these key components consume a lot of energy, the development of this process has become an urgent problem to be solved.

[0004] The loss of the above components themselves is not large, but to perform aging and performance verification on them, they need to be carried out according to the power and pulse width of actual working conditions, and this process consumes energy equivalent to that of the finished equipment. Taking the energy window as an example, for an energy window with a power of 500kW, a 500kW microwave source is required, and the microwave energy is introduced into the energy window through a waveguide; and because the power consumption of the energy window is very low (generally not more than 1kW), the power output from the energy window after aging is also close to 500kW, so a 500kW load is also required to dissipate the energy. The effective power loss of the entire process is the actual loss of the energy window not exceeding 1kW, and the remaining large amount of energy will be wasted, which is very uneconomical.

[0005] At present, key components are generally not aged separately, but are often aged together with finished products. This approach can avoid the huge energy consumption caused by aging key components separately, but it also brings huge hidden dangers to product production. Only after the production, assembly and welding of the product are completed and the test phase is entered can the performance evaluation and aging of key components be carried out, which greatly reduces the yield rate. In order to alleviate the hidden dangers caused by the use of unaged components in product production, the common practice is to use other tests to preliminarily screen key components to screen out most defective components. Taking the energy transmission window as an example, commonly used test methods include standing wave ratio test, insertion loss test, low-power performance test, etc. The aging of the traveling wave resonant ring can further screen components on the basis of these tests, and thoroughly screen out qualified products through full-power tests of the components.

[0006] The present invention proposes a device for aging and performance verification of medium and low frequency high power microwave key components used in high energy particle accelerators and controlled thermonuclear fusion superconducting tokamak devices. The device includes two types: low-pass type and band-pass type. The low-pass type is suitable for low frequency devices below several hundred MHz, and the band-pass type is suitable for medium frequency devices from several hundred MHz to several GHz. Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] The invention aims to solve the problem of excessive energy consumption in the aging process of high-power microwave equipment or components in devices such as high-energy particle accelerators and controlled thermonuclear fusion superconducting tokamak devices.

[0009] (II) Technical solution

[0010] To achieve the above purpose, the present invention is implemented through the following technical solutions: a traveling wave resonant ring for high-power microwave device aging, the traveling wave resonant ring is a low-frequency microwave device, the traveling wave resonant ring includes a coupler and a transmission line, the coupler includes 4 ports, the ports include a coupling port and an isolation port. The two ends of the transmission line are respectively connected to the coupling port and the isolation port of the coupler, and the unit under test is inserted in the middle, forming a traveling wave resonant ring together with the coupler.

[0011] Preferably, the port also includes an input port and an output port, and microwave power is continuously input from the input port of the coupler to maintain the microwave power of the entire system. The output port is connected to a matching load to absorb excess power and prevent reflection.

[0012] Preferably, the coupler is a coupler with a low coupling degree, with a typical value between 10 and 20 dB. The coupler is typically in the form of a low-pass coupler or a band-pass coupler.

[0013] Preferably, the transmission line can be a coaxial line, a rectangular waveguide, a circular waveguide or other waveguide device for transmitting high-power microwaves.

[0014] Preferably, the input microwave power is coupled to the coupling port through a coupler, and then the power is transmitted along the transmission line, passes through the unit under test, and returns to the coupler from the isolation port to form a resonant ring.

[0015] Preferably, under the condition of phase matching of the traveling wave resonant ring, the power injected into the input port will be accumulated in the traveling wave resonant ring, so that the field intensity on the transmission line is continuously enhanced to achieve gain.

[0016] The preferred phase matching condition refers to that the electrical length of a wave transmitted in the resonant ring for one circle is an integer multiple of the wavelength, and at this time, the superposition effect of the field input to the resonant ring and the field transmitted in the resonant ring is enhanced.

[0017] Preferably, the unit under test has the characteristic of low loss.

[0018] Preferably, the transmission line also includes some coupling interfaces and other auxiliary interfaces for measuring power.

[0019] (III) Beneficial effects

[0020] The beneficial effect of the technical solution of the present invention is to achieve a higher power gain by using the traveling wave resonant ring, which can generally reach 20 to 50 times, thereby greatly reducing the input power required for the aging equipment or components, and achieving energy saving effect. For a 500kW device, if the traveling wave resonant ring is used for aging, the input power can be reduced to 10 to 25kW. The present invention has obvious practical value in reducing the energy consumption of aging. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is an example of a traveling wave resonant ring structure using a low-pass coupler;

[0022] Figure 2 It is a coupler of a low-pass structure traveling wave resonant ring;

[0023] Figure 3 It is an example of a traveling wave resonant ring structure using a bandpass coupler;

[0024] Figure 4 It is a coupler of a bandpass traveling wave resonant ring.

[0025] In the figure: 101, low-pass coupler; 102, coaxial transmission line; 103, power measurement unit; 104 unit under test; 105, input port; 106, output port; 107, coupling port; 108, isolation port; 109, coupling band; 201, band-pass coupler; 202, coaxial transmission line; 203, power measurement unit; 204, unit under test; 205, input port; 206, output port; 207, coupling port; 208, isolation port; 209, coupling hole. DETAILED DESCRIPTION

[0026] 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 only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0027] Embodiment 1:

[0028] Figure 1 Figure 2The figure shows a typical example of a traveling wave resonant ring using a low-pass coupler 101. Its structure includes a coupler 101, a coaxial transmission line 102, a power measurement unit 103, and a unit under test 104. The coupler 101 includes an input port 105, an output port 106, a coupling port 107, and an isolation port 108. The two ends of the transmission line 102 are respectively connected to the coupling port 107 and the isolation port 108 of the coupler 101, and the unit under test 104 is inserted in the middle. The input microwave power is coupled to the coupling port 107 through the coupler 101, and then the power is transmitted along the transmission line 102, passes through the unit under test 104, and returns to the coupler 101 from the isolation port 108 to form a resonant ring. The low-pass coupler 101 uses a coupling strip type low-pass coupler 101, and the typical value is between 10 and 20 dB. It uses a coupling strip 109 as a power coupling component. The low-pass coupler 101 has a large power capacity and can withstand a power of more than 600kW. The low-pass coupler 101 is a low-frequency device with a typical operating frequency of no more than 400MHz. Higher frequency devices are more difficult to design and have lower power capacity, which does not meet the original design intention. Figure 1 Figure 2 In the transmission line 102, a high-power, large-size coaxial transmission line 102 is used. The transmission line 102 has a wide single-mode transmission range and high power capacity. The transmission line 102 has the characteristics of low loss. Higher loss will reduce the gain of the traveling wave resonant ring. Under the phase matching condition of the traveling wave resonant ring, the power injected into the input port 105 will accumulate in the traveling wave resonant ring, so that the field strength on the transmission line 102 is continuously enhanced to achieve gain. The phase matching condition refers to the electrical length of the wave transmitted in the resonant ring for one circle is an integer multiple of the wavelength. At this time, the superposition effect of the field input to the resonant ring and the field transmitted in the resonant ring is enhanced. Figure 1 Figure 2 The power measuring unit 103 measures the power in the traveling wave resonant ring, and is used to detect the power in the traveling wave resonant ring in real time during the product aging process. Figure 1 Figure 2 In the embodiment, the unit under test 104 is a passive microwave power device, such as an energy transmission window, which has the characteristic of low insertion loss. The requirement of low loss makes the introduction of such devices have little effect on the field strength in the traveling wave resonant ring. The introduction of devices with higher insertion loss will greatly increase the total insertion loss on the traveling wave resonant ring, and the gain on the traveling wave resonant ring will be greatly reduced.

[0029] Embodiment 2:

[0030] Figure 3 Figure 4The figure shows a typical example of a traveling wave resonant ring using a bandpass coupler 201. Its structure includes a coupler 201, a coaxial transmission line 202, a power measurement unit 203, and a unit under test 204. The coupler 201 includes an input port 205, an output port 206, a coupling port 207, and an isolation port 208. The two ends of the transmission line 202 are respectively connected to the coupling port 207 and the isolation port 208 of the coupler 201, and the unit under test 204 is inserted in the middle. The input microwave power is coupled to the coupling port 207 through the coupler 201, and then the power is transmitted along the transmission line 202, passes through the unit under test 204, and returns to the coupler 201 from the isolation port 208 to form a resonant ring. Figure 3 Figure 4 In the embodiment, the bandpass coupler 201 adopts a multi-hole coupled rectangular waveguide structure, with a typical value between 10 and 20 dB. A plurality of coupling holes 209 are opened on the narrow side of the rectangular waveguide of the coupler 201 to couple power to the coupling port 207. The structure has a narrowband bandpass characteristic. Under this structure, the traveling wave resonant ring can operate at a higher frequency. The typical operating frequency of the traveling wave resonant ring of this structure is 5 GHz and below, because the output power is required to be above 600 kW. Too high a frequency makes the structure of the traveling wave resonant ring too small, the power capacity is insufficient, and it is easy to ignite. Under the phase matching condition of the traveling wave resonant ring, the power injected into the input port 205 will accumulate in the traveling wave resonant ring, thereby continuously enhancing the field strength on the transmission line 202 and achieving gain. The phase matching condition refers to the electrical length of a wave transmitted in the resonant ring for one circle being an integer multiple of the wavelength. At this time, the superposition effect of the field input to the resonant ring and the field transmitted in the resonant ring is enhanced. Figure 3 Figure 4 In the figure, the transmission line 202 adopts a rectangular waveguide, the cross-sectional dimensions of which are the same as those of the waveguide of the bandpass coupler 201, and the loss at the waveguide connection is small. In the figure, the power measurement unit 203 measures the power in the traveling wave resonant ring, which is used for real-time detection of the microwave power in the traveling wave resonant ring during the product aging process. In the figure, the measured unit 204 is optimally equipped with an interface having the same dimensions as the rectangular waveguide of the transmission line 202, which has the minimum power loss. At the same time, in order to meet different needs, a conversion unit can be added to convert the transmission line 202 into a circular waveguide or a coaxial line.

Claims

1. A traveling wave resonant ring for aging high-power microwave devices, the traveling wave resonant ring is a microwave device that can achieve field intensity enhancement, characterized in that: The traveling wave resonant ring comprises a coupler and a transmission line, the coupler comprises four ports, the ports include a coupling port and an isolation port. The two ends of the transmission line are respectively connected to the coupling port and the isolation port of the coupler, and the unit under test is inserted in the middle, forming a traveling wave resonant ring together with the coupler.

2. The traveling wave resonant ring for aging of high power microwave devices according to claim 1, characterized in that: The port also includes an input port and an output port. Microwave power is continuously input from the input port of the coupler to maintain the microwave power of the entire system. The output port is connected to a matching load to absorb excess power and prevent reflection.

3. The traveling wave resonant ring for aging of high power microwave devices according to claim 1, characterized in that: The coupler is a low coupling coupler, and a typical value is between 10 and 20 dB.

4. The traveling wave resonant ring for high power microwave device aging according to claim 1, characterized in that: The coupler is typically in the form of a low-pass coupler or a band-pass coupler.

5. The traveling wave resonant ring for aging of high power microwave devices according to claim 1, characterized in that: The transmission line is a waveguide device that can transmit high-power microwaves, and can be one of a coaxial line, a rectangular waveguide, and a circular waveguide.

6. The traveling wave resonant ring for high power microwave device aging according to claim 1, characterized in that: Under the condition of phase matching of the traveling wave resonant ring, the power injected into the input port will be accumulated on the traveling wave resonant ring, so that the field intensity on the transmission line is continuously enhanced to achieve gain.

7. A traveling wave resonant ring for aging high power microwave devices according to claim 6, characterized in that: The phase matching condition refers to that the electrical length of a wave transmitted in the resonant ring for one circle is an integer multiple of the wavelength, and at this time, the superposition effect of the field input to the resonant ring and the field transmitted in the resonant ring is enhanced.

8. The traveling wave resonant ring for aging of high power microwave devices according to claim 1, characterized in that: The unit under test has the characteristic of low loss.

9. The traveling wave resonant ring for aging of high power microwave devices according to claim 1, characterized in that: The transmission line also includes a coupling interface and an auxiliary interface for measuring power.

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