Method and apparatus for supplying high output RF power

Abstract

The present invention discloses a method and an apparatus for supplying high output RF (Radio Frequency) power. According to one embodiment of the present disclosure, an apparatus for supplying high output RF power may include: an LLRF (Low Level Radio Frequency) module for supplying first RF power to a first power amplifier; a first power amplifier that amplifies the first RF power to generate second RF power, and supplies the second RF power to a second power amplifier; a modulator that supplies a high voltage pulse to the second power amplifier; and the second power amplifier that generates a third RF power using the second RF power and the high voltage pulse.

Description

Technical Field

[0001] This invention relates to a method and apparatus for supplying high-output RF (Radio Frequency) power. More specifically, it relates to a method and apparatus for supplying power and voltage to a Klystron amplifier and controlling the phase and amplitude of the RF power by performing feedforward control to supply high-output RF power. Background Technology

[0002] The following description provides background information related to this embodiment only and does not constitute prior art.

[0003] Radio frequency (RF) refers to the frequencies used in wireless communication applications via radio waves. RF can correspond to frequencies with oscillation numbers between 3 kHz and 3 THz. High-output RF power is used in RF linear accelerator tubes. To generate high-output RF power, an RF power amplifier can be used. An RF power amplifier is an electronic amplifier that converts low-power RF signals into high-power RF signals. There are two main methods for power control of RF power amplifiers.

[0004] One type of power control method is based on closed-loop control. This method primarily controls the final output power by controlling the input power of the RF power amplifier. The other type is based on open-loop control. This method primarily controls the final output power by controlling the voltage. When using an RF power amplifier to generate the high output RF power required for an RF linear accelerator tube, the high output RF power generated by the RF power amplifier must reach a certain magnitude, and the phase and amplitude of this RF power must be stable. Summary of the Invention

[0005] Technical issues This disclosure enables the amplification of RF (Radio Frequency) power using a klystron amplifier.

[0006] Furthermore, according to one embodiment, feedforward control can be used to improve the stability of high-output RF power.

[0007] Furthermore, according to one embodiment, the stability of the amplitude and phase of high-output RF power can be improved.

[0008] The problems to be solved by the present invention are not limited to those mentioned above, and those skilled in the art will clearly understand from the following description other problems not mentioned.

[0009] Problem-solving methods The apparatus for supplying high-output RF (Radio Frequency) power disclosed herein may include: an LLRF (Low Level Radio Frequency) module that supplies first RF power to a first power amplifier; the first power amplifier that amplifies the first RF power to generate second RF power and supplies the second RF power to a second power amplifier; a modulator that supplies a high-voltage pulse to the second power amplifier; and the second power amplifier that uses the second RF power and the high-voltage pulse to generate third RF power.

[0010] The method for supplying high-output RF power disclosed herein may include: supplying first RF power to a first power amplifier; amplifying the first RF power to generate second RF power; supplying the second RF power to a second power amplifier; supplying a high-voltage pulse to the second power amplifier; and generating third RF power using the second RF power and the high-voltage pulse.

[0011] The computer program disclosed herein is combined with a computing device as hardware and stored in a computing device-readable recording medium for performing the following steps: supplying a first RF power to a first power amplifier; amplifying the first RF power to generate a second RF power; supplying the second RF power to a second power amplifier; supplying a high-voltage pulse to the second power amplifier; and generating a third RF power using the second RF power and the high-voltage pulse.

[0012] The computer-readable recording medium disclosed herein is a computer-readable recording medium storing instructions that, when executed by the computer, cause the computer to perform the following steps: supplying a first RF power to a first power amplifier; amplifying the first RF power to generate a second RF power; supplying the second RF power to a second power amplifier; supplying a high-voltage pulse to the second power amplifier; and generating a third RF power using the second RF power and the high-voltage pulse.

[0013] Invention Effects According to this disclosure, it has the effect of amplifying RF (Radio Frequency) power using a klystron amplifier.

[0014] Furthermore, according to one embodiment, it has the effect of improving the stability of high-output RF power by utilizing feedforward control.

[0015] Furthermore, according to one embodiment, it has the effect of improving the stability of the amplitude and phase of high-output RF power.

[0016] The effects that can be obtained by this disclosure are not limited to those mentioned above. Those skilled in the art to which this disclosure pertains will clearly understand other effects not mentioned through the following description. Attached Figure Description

[0017] Figure 1 This is a block diagram illustrating an embodiment of the present disclosure of a device for supplying high-output RF (Radio Frequency) power.

[0018] Figure 2 This is a diagram illustrating an embodiment of the present disclosure of an RF linear accelerator tube and a device for supplying high-output RF power.

[0019] Figure 3 This is a diagram illustrating a modulator and a klystron amplifier according to an embodiment of the present disclosure.

[0020] Figure 4 This is a diagram illustrating the voltage supplied by the modulator in one embodiment of the present disclosure.

[0021] Figure 5a and Figure 5b This is a diagram illustrating the amplitude and phase of the high-output RF power in an embodiment of this disclosure.

[0022] Figure 6a and Figure 6b This is a diagram illustrating the amplitude and phase of the high-output RF power in another embodiment of this disclosure.

[0023] Figure 7 This is a diagram illustrating a method for supplying high-output RF power according to an embodiment of the present disclosure. Detailed Implementation

[0024] The following detailed description of some embodiments of the present disclosure is provided with reference to the exemplary accompanying drawings. It should be noted that when adding reference numerals to the constituent elements of each figure, the same reference numerals are used as much as possible for the same constituent elements, even if they are indicated in different figures. Furthermore, when describing the present disclosure, detailed descriptions of relevant known structures or functions are omitted if it is determined that such detailed descriptions may obscure the main points of the disclosure.

[0025] When describing the constituent elements of embodiments of this disclosure, reference numerals such as first, second, i), ii), a), and b) may be used. These reference numerals are used only to distinguish the constituent element from other constituent elements and do not limit the nature, order, or sequence of the corresponding constituent elements. In the specification, when a part is referred to as "comprising" or "having" a constituent element, unless expressly stated to the contrary, it does not mean that other constituent elements are excluded, but rather that other constituent elements may be further included.

[0026] The detailed description disclosed below, in conjunction with the accompanying drawings, is intended to describe exemplary embodiments of the present disclosure and is not intended to show the only embodiments in which the present disclosure may be implemented.

[0027] Figure 1 This is a block diagram illustrating an embodiment of the present disclosure of a device for supplying high-output RF (Radio Frequency) power. High-output RF power is required to operate the RF linear accelerator tube. For example, the peak value of such high-output RF power is 1.5 MW, and the average value of such high-output RF power may correspond to 150 kW. Here, the duty cycle of such high-output RF power may correspond to 10%. For example, the pulse length of such high-output RF power is 800 microseconds, and the repetition rate of such high-output RF power may correspond to 120 Hz. For example, the amplitude of such high-output RF power may require stability within ±1%. For example, the phase of such high-output RF power may require stability within ±1 degree.

[0028] Reference Figure 1The apparatus for supplying high-output RF power may include an LLRF (Low Level Radio Frequency) module 110, a power amplifier 120, a modulator 130, and a klystron amplifier 140. The apparatus for supplying high-output RF power disclosed herein can supply the RF power required by the RF linear accelerator tube. The LLRF module 110 can supply a predetermined amount of RF power to the power amplifier 120. For example, the LLRF module 110 can supply several megawatts (mW) of power to the power amplifier 120. Feedforward control can be performed using the LLRF module 110. Feedforward control can be performed by changing the phase or amplitude of the RF power supplied by the LLRF module 110 to the power amplifier 120. Specifically, the LLRF module 110 can change at least one of the phase or amplitude of the RF power supplied to the power amplifier 120 based on at least one of the amplitude and phase of the high-output RF power generated by the klystron amplifier 140. Accordingly, the LLRF module 110 can supply the modified RF power to the power amplifier 120. Through feedforward control, the stability of the RF power supplied by the device providing high-output RF power can be improved. The power amplifier 120 may correspond to an SSPA (Solid State Power Amplifier). An SSPA may correspond to a power amplifier made using solid-state semiconductors. An SSPA may be made using solid-state components that are not vacuum tubes.

[0029] Power amplifier 120 amplifies the RF power supplied from LLRF module 110. Power amplifier 120 supplies amplified RF power to klystron amplifier 140. For example, power amplifier 120 can receive and amplify several milliwatts (mW) of RF power from LLRF module 110 and supply 100W of power to klystron amplifier 140. Modulator 130 supplies high-voltage pulses to klystron amplifier 140. For example, modulator 130 can supply a 90kV pulse voltage to klystron amplifier 140. Modulator 130 may utilize a high-voltage switch and a high-voltage capacitor to supply voltage to klystron amplifier 140. The voltage generated by modulator 130 may produce a droop. For example, a 5% droop may occur.

[0030] The klystron amplifier 140 utilizes the RF power supplied by the power amplifier 120 and the voltage supplied by the modulator 130 to generate high-output RF power. Because the klystron amplifier 140 uses a high-performance resonator for input and output, it exhibits superior frequency stability compared to other amplifiers. For example, the klystron amplifier 140 can operate at frequencies around 200 MHz to 100 GHz. The klystron amplifier 140 may include two resonators. In the klystron amplifier 140, electron beams undergo electron bundling when passing through the first resonator, generating a standing wave. The electron flow entering the first resonator can be repeatedly accelerated and decelerated. The standing wave electric field can cause the electron flow to be bundled at specific locations. When such a bundled electron flow enters the second resonator, a strong standing wave can be formed again. This standing wave can be used to output the amplified RF power to the outside via a coupler.

[0031] The klystron amplifier 140 can correspond to an RF amplifier. The gain of the klystron amplifier 140 can be 50 dB. The efficiency of the klystron amplifier 140 can be 60%. For example, the klystron amplifier 140 can generate 1.5 MW of RF power. By coupling out the high-output RF power from the klystron amplifier 140, a portion of the RF power can be processed as a signal. Using this processed portion of the RF power, the stability of the phase and amplitude of the high-output RF power can be measured.

[0032] Figure 2 This diagram illustrates an embodiment of an RF linear accelerator tube and a device for supplying high-output RF power. An RF linear accelerator tube is a device that uses an RF electromagnetic field to apply energy to linearly moving charged particles to accelerate them. RF linear accelerator tubes vary widely in size, from tens of kilometers (km) to tens of centimeters (cm), and are widely used in industry, medicine, research, and military applications. High-output RF power is required to operate an RF linear accelerator tube. For example, an RF linear accelerator tube can be used to accelerate a proton beam to 10 MeV. In this case, the peak amplitude of the required high-output RF power can correspond to 1.5 MW.

[0033] Reference Figure 2Two modulators supply high-voltage pulses to two klystron amplifiers. Two LLRF modules supply low-power RF power to two driver amplifiers. The driver amplifiers amplify the low-power RF power supplied from the two LLRF modules. The driver amplifiers then supply the amplified RF power to the two klystron amplifiers. The two klystron amplifiers utilize the supplied RF power and the high-voltage pulses to generate high-output RF power. Feedforward control can be implemented using the two LLRF modules. Consequently, the stability of the high-output RF power generated by the two klystron amplifiers is improved.

[0034] One klystron amplifier supplies high-output RF power to a three-part RFQ (Radio Frequency Quadrupole) linear accelerator tube. Another klystron amplifier supplies high-output RF power to a two-part DTL (Drift Tube Linear) linear accelerator tube. The RFQ and DTL linear accelerator tubes can each use the supplied high-output RF power to accelerate charged particles.

[0035] Figure 3 This is a diagram illustrating a modulator and a klystron amplifier according to an embodiment of the present disclosure.

[0036] Reference Figure 3 The modulator may include two capacitor charging power supplies (CCPS), a capacitor bank, and a high-voltage switch. The CCPS generates a high voltage. A pulse can be generated using the capacitor bank and the high-voltage switch. The capacitor bank and the high-voltage switch can form a loop to generate the pulse. The generated high-voltage pulse can be supplied to a klystron amplifier. Due to the resistors, inductors, and capacitors present within the modulator, a voltage drop (droop) may occur in the high-voltage pulse.

[0037] Figure 4 This is a diagram illustrating the voltage supplied by the modulator in one embodiment of the present disclosure.

[0038] Reference Figure 4 The high-voltage pulse supplied by the modulator to the klystron amplifier may result in a voltage drop. For example, in a high-voltage pulse generated by the modulator, with an output voltage of 67 kV, a pulse width of 1.8 ms, and a klystron amplifier as the load, a voltage drop of 3 kV may occur. This voltage drop percentage corresponds to 4.4% of the output voltage.

[0039] Figure 5a and Figure 5b This is a diagram illustrating the amplitude and phase of the high-output RF power in an embodiment of this disclosure.

[0040] Reference Figure 5a Without using the LLRF module for feedforward control, the klystron amplifier can output high-output RF power. This high-output RF power can be coupled out, and a portion of the RF power can be signal-processed. The amplitude of this signal-processed portion of the RF power can be measured. The maximum amplitude of the signal-processed portion of the RF power is 0.0508 mW, and the minimum amplitude corresponds to 0.0478 mW. Accordingly, the stability of the high-output RF power amplitude corresponds to ±3%.

[0041] Reference Figure 5b Without using the LLRF module for feedforward control, the klystron amplifier can output high-output RF power. This high-output RF power can be coupled out, and a portion of the RF power can be signal-processed. The phase of this signal-processed portion of the RF power can be measured. The maximum phase of this signal-processed portion of the RF power can be 78.55 degrees, and the minimum phase corresponds to 66.18 degrees. Accordingly, the phase stability of the high-output RF power can correspond to ±6 degrees.

[0042] Figure 6a and Figure 6b This is a diagram illustrating the amplitude and phase of the high-output RF power in another embodiment of this disclosure.

[0043] Reference Figure 6a By utilizing the LLRF module to perform feedforward control, the klystron amplifier can output high-output RF power. This high-output RF power can be coupled out, and a portion of the RF power can be signal-processed. The amplitude of this signal-processed portion of the RF power can be measured. The maximum amplitude of this signal-processed portion of the RF power is 0.0513 mW, and the minimum amplitude corresponds to 0.0503 mW. Accordingly, the stability of the high-output RF power amplitude corresponds to ±0.9%.

[0044] Reference Figure 6bBy utilizing the LLRF module to perform feedforward control, the klystron amplifier can output high-output RF power. This high-output RF power can be coupled out, and a portion of the RF power can be signal-processed. The phase of this signal-processed portion of the RF power can be measured. The maximum phase of this signal-processed portion of the RF power can be 231.6 degrees, and the minimum phase corresponds to 229.8 degrees. Accordingly, the phase stability of the high-output RF power can be ±0.5 degrees.

[0045] Figure 7 This is a diagram illustrating a method for supplying high-output RF power according to an embodiment of the present disclosure.

[0046] Reference Figure 7 The device supplying high-output RF power can supply first RF power to a first power amplifier (S710). The device supplying high-output RF power can amplify the first RF power to generate second RF power (S720). The device supplying high-output RF power can supply the second RF power to a second power amplifier (S730). The device supplying high-output RF power can supply a high-voltage pulse to the second power amplifier (S740). The device supplying high-output RF power can generate a third RF power using the second RF power and the high-voltage pulse (S750). The first power amplifier can correspond to an SSPA (Special Power Spatial Amplifier). The second power amplifier can correspond to a klystron amplifier. The device supplying high-output RF power can supply a fourth RF power to the first power amplifier based on at least one of the amplitude and phase of the third RF power. The high-voltage pulse can be generated by a modulator using a capacitor bank and a high-voltage switch. The stability of the amplitude and phase of the third RF power can be measured by signal processing of the third RF power. With the fourth RF power, the amplitude and phase of the third RF power can be maintained within a predetermined range.

[0047] Each component of the apparatus or method of the present invention can be implemented in hardware or software, or in a combination of hardware and software. Furthermore, the function of each component can be implemented in software, and the microprocessor can also be implemented to execute the software functions corresponding to each component.

[0048] The various implementations of the systems and technologies described in this specification can be implemented using digital electronic circuits, integrated circuits, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), computer hardware, firmware, software, and / or combinations thereof. These various implementations may include implementations with more than one computer program capable of running on a programmable system. The programmable system includes at least one programmable processor (which may be an application-specific processor or a general-purpose processor) configured to receive and transmit data and instructions from a storage system, at least one input device, and at least one output device. The computer program (also referred to as a program, software, software application, or code) includes instructions for the programmable processor and is stored in a computer-readable recording medium.

[0049] Computer-readable recording media include all kinds of recording devices capable of storing data that can be read by a computer system. Such computer-readable recording media can be non-volatile or non-transitory media such as read-only memory (ROM), compact optical disc read-only memory (CD-ROM), magnetic tape, floppy disk, memory card, hard disk, optical-magneto-optical disk, and storage devices, and may further include transient media such as data transmission media. Furthermore, computer-readable recording media can be distributed across computer systems connected via a network to store and execute computer-readable code in a distributed manner.

[0050] Although the flowcharts / timing diagrams in this specification depict steps executed sequentially, this is merely an illustrative description of the technical concept of one embodiment of this disclosure. In other words, those skilled in the art to which this embodiment pertains will be able to perform various modifications and variations without departing from the essential characteristics of this embodiment, by changing the order depicted in the flowcharts / timing diagrams or by executing one or more steps in parallel. Therefore, the flowcharts / timing diagrams are not limited to a specific time sequence.

[0051] The above description is merely an exemplary description of the technical concept of this embodiment. Those skilled in the art to which this embodiment pertains will be able to make various modifications and variations without departing from the essential characteristics of this embodiment. Therefore, this embodiment is not intended to limit the technical concept of this embodiment, but rather to illustrate it. The scope of the technical concept of this embodiment is not limited by such embodiments. The protection scope of this embodiment should be interpreted in accordance with the following claims, and all technical concepts within the equivalent scope should be interpreted as falling within the scope of the rights of this embodiment.

[0052] Cross-referencing of related applications This patent application claims priority to Korean Patent Application No. 10-2023-0051767, filed on April 20, 2023, the entire contents of which are incorporated herein by reference.

Claims

1. A device for supplying high-output RF power, comprising: The LLRF module supplies first RF power to the first power amplifier; The first power amplifier amplifies the first RF power to generate a second RF power, and supplies the second RF power to the second power amplifier; A modulator that supplies high-voltage pulses to the second power amplifier; as well as The second power amplifier uses the second RF power and the high-voltage pulse to generate a third RF power.

2. The apparatus according to claim 1, wherein, The first power amplifier corresponds to SSPA.

3. The apparatus according to claim 1, wherein, The second power amplifier corresponds to the klystron amplifier.

4. The apparatus according to claim 1, wherein, The LLRF module supplies fourth RF power to the first power amplifier based on at least one of the amplitude and phase of the third RF power.

5. The apparatus according to claim 1, wherein, The modulator generates the high-voltage pulse using a capacitor bank and a high-voltage switch.

6. The apparatus according to claim 4, wherein, The stability of the amplitude and the stability of the phase of the third RF power are measured by performing signal processing on the third RF power.

7. The apparatus according to claim 4, wherein, The amplitude and phase of the third RF power are maintained within a predetermined range by the fourth RF power.

8. A method performed by a device supplying high-output RF power, comprising: The step of supplying first RF power to the first power amplifier; The step of amplifying the first RF power to generate the second RF power; The step of supplying the second RF power to the second power amplifier; The step of supplying a high-voltage pulse to the second power amplifier; as well as The step of generating third RF power using the second RF power and the high-voltage pulse.

9. The method according to claim 8, wherein, The first power amplifier corresponds to SSPA.

10. The method according to claim 8, wherein, The second power amplifier corresponds to the klystron amplifier.

11. The method of claim 8, further comprising: The step of supplying fourth RF power to the first power amplifier based on at least one of the amplitude and phase of the third RF power.

12. The method according to claim 8, wherein, The high-voltage pulse is generated by a modulator using a capacitor bank and a high-voltage switch.

13. The method according to claim 11, wherein, The stability of the amplitude and the stability of the phase of the third RF power are measured by performing signal processing on the third RF power.

14. The method according to claim 11, wherein, The amplitude and phase of the third RF power are maintained within a predetermined range by the fourth RF power.

15. A computer program, which is incorporated into a computing device as hardware and stored in a recording medium readable by the computing device for performing the following steps: The step of supplying first RF power to the first power amplifier; The step of amplifying the first RF power to generate the second RF power; The step of supplying the second RF power to the second power amplifier; The step of supplying a high-voltage pulse to the second power amplifier; as well as The step of generating third RF power using the second RF power and the high-voltage pulse.

16. A computer-readable recording medium storing instructions, which, when executed by the computer, cause the computer to perform the following steps: The step of supplying first RF power to the first power amplifier; The step of amplifying the first RF power to generate the second RF power; The step of supplying the second RF power to the second power amplifier; The step of supplying a high-voltage pulse to the second power amplifier; as well as The step of generating third RF power using the second RF power and the high-voltage pulse.

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