Solid-state power source system of E-type digital pulse power amplifier based on GaN device and medical electronic equipment

Abstract

The invention provides a solid-state power source system of an E-type digital pulse power amplifier based on a GaN device and medical electronic equipment, and the system comprises a digital pulse generation module, at least one filtering amplification path and an all-in-one power combiner module, and the filtering and amplifying path comprises a high-frequency switch driving module, a gallium nitride-based E-type power amplifier module, an impedance matching circuit module and a multi-order filter module. According to the technical scheme, the characteristics of a GaN device can be fully exerted, and the E-type digital pulse power amplifier topology circuit structure is high in efficiency, high in power density, simple in structure and high in reliability so as to meet the requirements of electronic and electrical equipment of a medical particle accelerator for a solid-state power source.

Description

Technical Field

[0001] This invention relates to the field of radio frequency power amplification technology, and is mainly applied to the field of solid-state power sources in medical particle accelerator electronic and electrical equipment. Specifically, it relates to a solid-state power source system based on a GaN device-based Class E digital pulse power amplifier and medical electronic equipment. Background Technology

[0002] In the field of solid-state power sources for electronic and electrical equipment in medical particle accelerators, traditional solid-state power sources in medical particle accelerators employ conventional Class AB RF power sources based on metal-oxide-semiconductor (MOS) devices. However, in the high-frequency, high-power applications required by medical particle accelerators, the silicon-based devices used in traditional technologies have inherent defects such as low electron mobility and low breakdown electric field strength, making it difficult to further improve the power amplifier efficiency, which is typically below 60%, and the power density is low, failing to meet the requirements of miniaturization and high integration in medical equipment. At the same time, MOS devices generate a lot of heat when operating at high frequencies, making the heat dissipation system design complex and increasing the size, weight, and cost of the equipment. Especially in medical equipment with high requirements for space and stability, its application is severely limited.

[0003] Gallium nitride (GaN) devices, as a typical representative of wide-bandgap semiconductor materials, possess excellent characteristics such as high electron mobility, high breakdown electric field strength, and high temperature resistance, which can significantly improve the efficiency and power density of power amplifiers. However, the current topology design of Class E power amplifiers based on GaN devices is not perfect and fails to fully utilize the performance advantages of GaN devices. Common problems include complex matching networks, large switching losses, and unstable efficiency over a wide frequency range, which restricts the further application of GaN devices in solid-state power sources for medical particle accelerators.

[0004] Therefore, a technical solution is needed that can fully utilize the characteristics of GaN devices and has a Class E digital pulse power amplifier topology circuit structure with high efficiency, high power density, simple structure and high reliability, in order to meet the requirements of medical particle accelerator electronic and electrical equipment for solid-state power sources. Summary of the Invention

[0005] The present invention aims to provide a solid-state power source system and medical electronic equipment for a GaN-based Class E digital pulse power amplifier, which can fully utilize the characteristics of GaN devices and has a high-efficiency, high-power-density, simple and reliable Class E digital pulse power amplifier topology circuit structure to meet the requirements of medical particle accelerator electronic and electrical equipment for solid-state power sources.

[0006] According to one aspect of the present invention, a solid-state power source system based on a GaN device-based Class E digital pulse power amplifier is provided, comprising: a digital pulse generation module, at least one filtering and amplification path, and a multi-function power combiner module, wherein the filtering and amplification path includes a high-frequency switch driving module, a gallium nitride-based Class E power amplifier module, an impedance matching circuit module, and a multi-stage filter module, wherein... The input terminal of the digital pulse generator module receives signals from an external host computer, and the output terminal of the digital pulse generator module is electrically connected to the input port of the high-frequency switch drive module to generate a square wave signal with adjustable frequency, duty cycle, and amplitude. The output port of the high-frequency switch drive module is electrically connected to the gate of the enhancement-mode gallium nitride high electron mobility transistor in the gallium nitride-based Class E power amplifier module to receive a square wave signal from the digital pulse generator module, thereby responding to changes in the square wave signal to drive the gallium nitride-based Class E power amplifier module. The gallium nitride-based Class E power amplifier module receives the square wave signal, filters and shapes it into a sine wave, and then outputs it to the impedance matching circuit module. The output port of the impedance matching circuit module is electrically connected to the input port of the multi-stage filter module, and is used to adjust the conjugate matching of the preceding and following stages and perform a single filtering operation. The output port of the multi-stage filter module is electrically connected to the input port of the all-in-one power combiner module for secondary filtering; The all-in-one power combiner module is used to perform power combining and three filtering operations to output the combined high-frequency, high-power signal.

[0007] According to some embodiments, the digital pulse generation module includes: an FPGA chip and a direct digital frequency synthesizer submodule, wherein, The FPGA chip receives control commands from the host computer to control the on or off signal of at least one of the filtering and amplification paths, and generates the square wave signal parameters with the required frequency, duty cycle, amplitude, and phase of the system and outputs them to the direct digital frequency synthesizer submodule. The direct digital frequency synthesizer submodule receives the square wave signal parameters from the FPGA chip and generates a corresponding square wave signal, which is then transmitted to the high-frequency switch driver module.

[0008] According to some embodiments, the high-frequency switch driving module includes: a driver, the input terminal of which is electrically connected to the output terminal of the direct digital frequency synthesizer submodule, and the output port of which is electrically connected to the gate of the enhancement-mode gallium nitride high electron mobility transistor in the power amplifier module, so as to receive and respond to the square wave signal, thereby outputting a driving signal to drive the power amplifier module.

[0009] According to some embodiments, the gallium nitride-based Class E power amplifier module adopts a Class E power amplifier architecture, including: an enhancement-mode gallium nitride high electron mobility transistor, a bias circuit unit, and a resonant network unit, wherein... The enhanced gallium nitride high electron mobility transistor receives the drive signal from the driver and switches at high speed under the control of the drive signal to obtain a power-amplified pulse current. The output of the bias circuit unit is electrically connected to the drain terminal of the enhanced gallium nitride high electron mobility transistor to provide a stable and adjustable anti-interference DC power supply. The input terminal of the resonant network unit is electrically connected to the drain terminal of the enhanced gallium nitride high electron mobility transistor, and the output terminal of the resonant network unit is electrically connected to the impedance matching circuit module to filter out harmonics and convert the pulse current into a sinusoidal voltage output to the impedance matching circuit module.

[0010] According to some embodiments, the impedance matching circuit module is an L-type impedance matching circuit. The input terminal of the L-type impedance matching circuit is electrically connected to the output terminal of the resonant network unit, and the output terminal of the L-type impedance matching circuit is connected to the multi-stage filter module to adjust the conjugate matching of the preceding and following stages and perform a single filtering operation.

[0011] According to some embodiments, the multi-order filter module includes at least one elliptic low-pass filter. The multi-order filter module matches elliptic low-pass filters of different orders according to the system harmonic suppression requirements to reduce high-order harmonic interference and complete secondary filtering.

[0012] According to some embodiments, the all-in-one power combiner module includes a multi-channel LC balun power combiner and / or Wilkinson power combiner adapted to the number of filter amplification paths, for power combining and completing three filtering steps.

[0013] According to some embodiments, the solid-state power source system further includes: The structure employs a dual high-frequency switch driver module to drive a gallium nitride-based Class E power amplifier module. The FPGA chip adjusts the duty cycle and phase difference of the square wave signal to achieve frequency multiplication, with a maximum operating frequency of 200MHz. The gallium nitride-based Class E power amplifier module employs two enhanced gallium nitride high electron mobility transistors (GNTs) with their sources electrically connected to each other, and the drains of the two GNTs are alternately grounded.

[0014] According to some embodiments, the frequency range of the square wave signal is 1-200MHz, the second harmonic suppression ratio is better than -20dB, and the third and higher harmonic suppression ratio is better than -30dB.

[0015] According to another aspect of the present invention, a medical electronic device is provided, comprising a solid-state power source system as described in any of the preceding claims.

[0016] According to embodiments of the present invention, by adding the gallium nitride-based Class E power amplifier module, the output power of the power amplifier can be flexibly adjusted using the drain bias voltage of the GaN device to adapt to different load requirements, thus expanding the application range of the circuit. It is particularly suitable for fields such as medical particle accelerator electronic and electrical equipment where high efficiency, power density, and reliability are required. A three-stage filtering design is employed, combining an impedance matching circuit module with a multi-order filter module and an all-in-one power combiner module, achieving a second harmonic suppression ratio better than -20dB and a third and higher harmonic suppression ratio better than -30dB, thereby improving particle acceleration accuracy.

[0017] According to some embodiments, the design scheme of this invention employs resonant network units and impedance transformation units. Compared with complex multi-stage matching structures, this greatly simplifies the design of the input and output matching networks, reduces design difficulty and circuit losses, improves circuit reliability, and ensures the stable operation of medical equipment. By combining intrinsic frequency operation with a frequency doubling mechanism, a wide bandwidth output of 1-200MHz is achieved, allowing adaptation to different models of medical particle accelerators without replacing core components.

[0018] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit the invention. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0020] Figure 1 This diagram illustrates a solid-state power source system for a GaN-based Class E digital pulse power amplifier according to an example embodiment.

[0021] Figure 2 A schematic diagram of a solid-state power source system for a GaN-based Class E digital pulse power amplifier is shown according to another exemplary embodiment.

[0022] Figure 3The circuit topology of a single-channel filter amplification path of a solid-state power source system based on a GaN device-based Class E digital pulse power amplifier according to an example embodiment is shown.

[0023] Figure 4 This diagram illustrates a dual-solid-state power source topology of a solid-state power source system based on a GaN-based Class E digital pulse power amplifier according to an example embodiment.

[0024] Figure 5 The diagram illustrates a solid-state power source system based on a GaN-based Class E digital pulse power amplifier, according to an example embodiment, featuring a frequency multiplier circuit topology based on a two-channel driver symmetrically driven gallium nitride device.

[0025] Figure 6 A flowchart of a method for a solid-state power source system according to an example embodiment is shown. Detailed Implementation

[0026] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that the invention will be thorough and complete, and the concept of the exemplary embodiments will be fully conveyed to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0027] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a full understanding of embodiments of the invention. However, those skilled in the art will recognize that the technical solutions of the invention can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of the invention.

[0028] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0029] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0030] It should be understood that although the terms first, second, third, etc., may be used herein to describe various components, these components should not be limited by these terms. These terms are used to distinguish one component from another. Therefore, the first component discussed below may be referred to as the second component without departing from the teachings of the present invention. As used herein, the term "and / or" includes all combinations of any one and more of the associated listed items.

[0031] The user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this invention are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of related data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0032] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of exemplary embodiments, and the modules or processes in the drawings are not necessarily essential for implementing the present invention, and therefore cannot be used to limit the scope of protection of the present invention.

[0033] In the high-frequency, high-power applications required by medical particle accelerators, traditional silicon-based devices suffer from inherent defects such as low electron mobility and weak breakdown electric field strength, making it difficult to further improve power amplifier efficiency, which is typically below 60%, and low power density, failing to meet the miniaturization and high integration requirements of medical equipment. Meanwhile, MOS devices generate significant heat during high-frequency operation, complicating heat dissipation system design and increasing the size, weight, and cost of the equipment. This severely limits their application, especially in medical settings where space and stability are critical.

[0034] Gallium nitride (GaN) devices, as a typical representative of wide-bandgap semiconductor materials, possess excellent characteristics such as high electron mobility, high breakdown electric field strength, and high temperature resistance, which can significantly improve the efficiency and power density of power amplifiers. However, the current topology design of Class E power amplifiers based on GaN devices is not perfect and fails to fully utilize the performance advantages of GaN devices. Common problems include complex matching networks, large switching losses, and unstable efficiency over a wide frequency range, which restricts the further application of GaN devices in solid-state power sources for medical particle accelerators.

[0035] To address this, this invention proposes a solid-state power source system and medical electronic equipment based on a GaN-based Class E digital pulse power amplifier. This system fully utilizes the characteristics of GaN devices, featuring a high-efficiency, high-power-density, simple, and highly reliable Class E digital pulse power amplifier topology to meet the requirements of medical particle accelerator electronic and electrical equipment for solid-state power sources. According to the embodiment, by adding the GaN-based Class E power amplifier module, the output power of the power amplifier can be flexibly adjusted using the drain bias voltage of the GaN device to adapt to different load requirements, expanding the application range of the circuit, especially suitable for fields such as medical particle accelerator electronic and electrical equipment with high requirements for efficiency, power density, and reliability. A three-stage filtering design is employed, combining an impedance matching circuit module with a multi-order filter module and an all-in-one power combiner module, achieving a second harmonic suppression ratio better than -20dB and a third and higher harmonic suppression ratio better than -30dB, thus improving particle acceleration accuracy.

[0036] This invention aims to solve the technical problems of low efficiency and insufficient power density of Class E power amplifiers using silicon-based devices in existing medical particle accelerator solid-state power sources, as well as the complex matching, large switching losses, and unstable broadband efficiency of existing Class E power amplifier topologies based on MOS devices. The invention provides a Class E digital pulse power amplifier topology circuit structure based on GaN devices. The following describes an example embodiment of the invention with reference to the accompanying drawings.

[0037] Figure 1 This diagram illustrates a solid-state power source system for a GaN-based Class E digital pulse power amplifier according to an example embodiment.

[0038] Figure 2 A schematic diagram of a solid-state power source system for a GaN-based Class E digital pulse power amplifier is shown according to another exemplary embodiment.

[0039] See Figure 1 as well as Figure 2 The figure illustrates a solid-state power source system based on a GaN-based Class E digital pulse power amplifier, comprising: a digital pulse generation module 01, at least one filtering and amplification path 02, and an all-in-one power combiner module 03. The filtering and amplification path 02 includes a high-frequency switch driver module 0201, a gallium nitride-based Class E power amplifier module 0202, an impedance matching circuit module 0203, and a multi-stage filter module 0204.

[0040] According to some embodiments, the solid-state power source system of the present invention generates a precise and controllable square wave or pulse signal through a digital pulse generation module 01, which serves as the drive input for a Class E power amplifier. This signal is then fed into a Class E power amplification path composed of an enhanced GaN HEMT, achieving high-efficiency amplification under high-frequency operating conditions. Each amplification path includes a bias circuit, a resonant network, and an impedance matching structure to ensure that the device operates under zero-voltage switching (ZVS) conditions, minimizing switching losses. To improve output power, the system adopts a multi-channel parallel amplification architecture. After filtering, the output signals of each channel are coherently combined by an all-in-one power combiner module 03, effectively integrating multiple RF energy sources to output a high-power, high-stability RF signal. This fully leverages the advantages of GaN devices—high frequency, high efficiency, and high voltage withstand capability—and, combined with digital pulse drive and power combining technology, makes it suitable for applications with stringent power density and energy efficiency requirements, such as 5G communication, radar, and wireless power transmission, as well as high-frequency, high-power applications required in medical particle accelerators.

[0041] According to some embodiments, see Figure 1 as well as Figure 2 The digital pulse generation module 01 receives signals from an external host computer at its input terminal, and its output terminal is electrically connected to the input port of the high-frequency switch driver module 0201 to generate a square wave signal with adjustable frequency, duty cycle, and amplitude. The input terminal of the digital pulse generation module 01 receives control signals from the external host computer and, by parsing the host computer instructions, achieves precise control of the output pulse parameters. Its output terminal is electrically connected to the non-inverting input port (INP) and the inverting input port (INN) of the high-frequency switch driver module 0201, supplying a square wave signal with adjustable frequency, duty cycle, and amplitude to the driver module. This square wave signal serves as the driving reference for the Class E power amplifier, directly determining the turn-on and turn-off timing of the GaN HEMT switching device, thereby controlling the pulse shape and energy output of the RF output. The module is typically implemented based on FPGA or high-performance digital logic circuits, possessing high time resolution, low jitter, and fast response capabilities, supporting flexible digital modulation functions, and providing a high-precision, programmable pulse excitation source for the entire solid-state power source system.

[0042] According to some embodiments, see Figure 2The output port of the high-frequency switch drive module 0201 is electrically connected to the gate of the GaN HEMT (GaN High Electron Mobility Transistor) in the gallium nitride-based Class E power amplifier module 0202 to receive square wave signals from the digital pulse generation module 01, thereby driving the gallium nitride-based Class E power amplifier module 0202 in response to changes in the square wave signals. The OTH and OUTL output ports of the high-frequency switch drive module 0201 are electrically connected to the gate of the GaN HEMT in the gallium nitride-based Class E power amplifier module 0202 to receive square wave drive signals from the digital pulse generation module 01. The drive module converts the input low-voltage digital square wave signal into gate control signals with sufficient drive current and voltage swing through OTH (upper transistor output) and OUTL (lower transistor output) to quickly and accurately turn the GaN HEMT device on and off. This process ensures that the Class E power amplifier's switching transistors can accurately respond to the timing changes of the input square wave, achieving high-frequency, high-efficiency zero-voltage switching (ZVS) operation, thereby effectively reducing switching losses and improving overall power conversion efficiency. The drive module features low propagation delay, high dv / dt immunity, and negative voltage shutdown capability, fully matching the high-speed switching characteristics of the enhanced GaN HEMT, and is a key component ensuring the stable, reliable, and high-performance operation of the power amplifier.

[0043] According to some embodiments, see Figure 2 The gallium nitride-based Class E power amplifier module 0202 receives the square wave signal, filters and shapes it into a sine wave, and then outputs it to the impedance matching circuit module 0203. The output port of the gallium nitride-based Class E power amplifier module 0202 is electrically connected to the input port of the impedance matching circuit module 0203, used to transmit the high-frequency switching voltage waveform generated by the Class E power amplifier to subsequent circuits. When the Class E power amplifier is working, its output terminal presents an approximately sinusoidal voltage waveform formed by the combined action of GaN HEMT switching and resonant network. This waveform is filtered and shaped at the drain node, and already has good fundamental energy concentration characteristics. By connecting this output to the input terminal of the impedance matching circuit module 0203, the system further performs impedance transformation and harmonic suppression on the signal, ensuring that the output impedance is accurately matched with the subsequent load (such as transmission lines, accelerating cavities, or antennas), maximizing the transmission efficiency of RF power, and reducing losses and distortion caused by reflections. This design not only achieves a smooth transition from high-efficiency switching amplification to stable RF output, but also ensures reliable operation of the system in high-frequency, high-power applications (such as medical particle accelerators).

[0044] According to some embodiments, see Figure 2The output port of the impedance matching circuit module 0203 is electrically connected to the input port of the multi-order filter module 0204, used to adjust the conjugate matching between the preceding and following stages and perform primary filtering. The output port of the impedance matching circuit module 0203 is also electrically connected to the input port of the multi-order filter module 0204, used to achieve conjugate impedance matching between the preceding and following stages and to perform preliminary filtering of the RF signal output from the Class E power amplifier. The impedance matching circuit, through a rationally designed reactance network (such as an L-type, π-type, or T-type structure), transforms the output impedance of the power amplifier to the input impedance required by the Nth-order filter, ensuring efficient transmission of maximum power while suppressing signal reflection and gain fluctuations caused by impedance mismatch. Furthermore, the impedance matching circuit module 0203 also possesses a certain filtering function, which can further attenuate harmonic components and improve the purity of the signal spectrum, providing a good precondition for the subsequent refined filtering processing of the Nth-order filter. This cascaded design not only optimizes the overall frequency response characteristics of the system but also provides strong support for the stringent requirements of signal stability and electromagnetic compatibility in high-frequency, high-power applications (such as medical particle accelerators).

[0045] According to some embodiments, see Figure 2 The output port of the multi-order filter module 0204 is electrically connected to the input port of the all-in-one power combiner module 03 for secondary filtering to reduce the interference and impact of high-order harmonics on the system. Based on the elliptic low-pass filter design, the output port of the multi-order filter module 0204 is electrically connected to the input port of the all-in-one power combiner module 03 for secondary deep filtering of the RF signal after pre-impedance matching and preliminary filtering. This effectively suppresses high-order harmonics (such as 2nd, 3rd and higher harmonics) and switching noise generated by the Class E power amplifier, ensuring that the signal input to the power combiner has a high-purity fundamental frequency component. This significantly reduces the risk of harmonic energy superposition in the combining network, avoiding problems such as port mismatch, increased insertion loss, and excessive electromagnetic interference (EMI), thereby improving the spectral purity, operational stability, and electromagnetic compatibility of the entire solid-state power source system.

[0046] According to some embodiments, see Figure 1 and Figure 2The all-in-one power combiner module 03 is used for power combining and three-stage filtering to output a combined high-frequency, high-power signal. The all-in-one power combiner module 03 coherently combines the RF signals from multiple N-order filters, integrating the high-frequency power of each branch. It can be cascaded to achieve high-power output, forming a single high-power composite RF output. The all-in-one power combiner module 03 uses precise circuit design to ensure that each input signal maintains phase consistency and impedance matching during the combining process, maximizing combining efficiency and minimizing reflection and loss. The combined high-frequency, high-power signal has higher output capability and stability, meeting the requirements of high-power RF systems. The output port of the all-in-one power combiner module 03 can be directly connected to an external load or transmission system, enabling the transmission of high-efficiency, high-purity high-frequency, high-power signals to external devices (such as accelerator cavities, antennas, or industrial loads). It is widely applicable to applications with stringent power density and signal quality requirements, such as 5G communication, radar systems, and medical particle accelerators.

[0047] Figure 3 The circuit topology of a single-channel filter amplification path of a solid-state power source system based on a GaN device-based Class E digital pulse power amplifier according to an example embodiment is shown.

[0048] Figure 4 This diagram illustrates a dual-solid-state power source topology of a solid-state power source system based on a GaN-based Class E digital pulse power amplifier according to an example embodiment.

[0049] See Figure 3 and Figure 4 The digital pulse generation module 01 includes an FPGA chip and a direct digital frequency synthesizer submodule.

[0050] According to some embodiments, the FPGA chip receives control commands from the host computer to control the on / off signals of at least one of the filter amplification paths 02, and generates square wave signal parameters with the required frequency, duty cycle, amplitude, and phase, and outputs them to the direct digital frequency synthesizer submodule. The direct digital frequency synthesizer submodule receives the square wave signal parameters from the FPGA chip and generates corresponding square wave signals, which are then transmitted to the high-frequency switch driver module 0201. Further, the FPGA chip is connected to the host computer via an Ethernet or PCIe interface to generate control signals for the on / off of the filter amplification path 02, and to generate square wave signal parameters with the required frequency, duty cycle (adjustable from 5% to 50%), amplitude (adjustable from 0.5 to 3.3V), and phase (adjustable from 0 to 360°). Generally, the RF power output for medical proton accelerators is an operating frequency of 80MHz and a total output power of 1360W. Optionally, an FPGA chip of model XC7K325T and an AD9910 DDS module can be used. The FPGA receives instructions from the host computer (80MHz frequency, 50% duty cycle, 3.3V amplitude) via Ethernet, generates control signals and transmits them to the DDS module. The DDS module outputs an 80MHz square wave signal, which is buffered and sent to the INP port of the high-frequency switch driver module 0201. The INN port is grounded.

[0051] According to some embodiments, the high-frequency switch driver module 0201 includes: a driver, the input terminal of which is electrically connected to the output terminal of the direct digital frequency synthesizer submodule, and the output port of which is electrically connected to the gate of the enhancement-mode gallium nitride high electron mobility transistor in the power amplifier module, to receive and respond to the square wave signal, thereby outputting a drive signal to drive the power amplifier module. Further optionally, the high-frequency switch driver module may employ a driver of model LMG1020, including a power supply, an input signal interface, an output drive interface, and a ground terminal. The power supply provides the operating voltage for the driver, wherein the VDD port is connected to a 5V DC power supply, and the GND port is grounded. The input signal interface receives the square wave signal, the INP port is connected to the positive terminal of the output signal, the INN port is grounded, and the input signal swing is compatible with a 3.3V level. The output driver interface outputs the sink / pull current (peak pull-up current 7A, sink current 5A) and voltage (0-5V) to meet the turn-on and turn-off requirements of the GaN device. Specifically, the OTH port is connected in series with resistor R1 (1-10Ω), and the OTL port is connected in series with resistor R2 (1-10Ω). The other ends of R1 and R2 are connected in parallel to the gate of the GaN device in the Gallium Nitride-based Class E power amplifier module 0202, enabling rapid gate voltage switching. The high-frequency switch driver module operates in the frequency range of 1-100MHz and supports narrow pulse drive with a pulse width ≥1ns. Optionally, [the following text is missing from the original and can be omitted]. Figure 3 The LMG1020 driver is used, with the VDD port connected to a 5V DC power supply; the OUTH port is connected in series with a 1Ω resistor R1, and the OUTL port is connected in series with a 1Ω resistor R2. The other ends of R1 and R2 are connected to the gate of the GaNHEMT of the EPC2012C; the driver operates at a frequency of 80MHz, outputs a drive voltage of 0-5V, and has a rise time of 0.4ns, ensuring fast switching of the GaN device.

[0052] The gallium nitride-based Class E power amplifier module 0202 adopts a Class E power amplifier architecture, including: an enhanced gallium nitride high electron mobility transistor, a bias circuit unit, and a resonant network unit.

[0053] According to some embodiments, the enhancement-mode gallium nitride high electron mobility transistor receives a drive signal from the driver and switches at high speed under the control of the drive signal to obtain a power-amplified pulse current. The enhancement-mode GaN HEMT device has a gate threshold voltage of 0.8-2.5V and a drain breakdown voltage ≥200V, making it suitable for high-frequency, high-current applications. Optionally, see... Figure 3 The Gallium Nitride-based Class E power amplifier module 0202 can use an enhanced GaN HEMT device (gate threshold 1.4V, drain breakdown 200V) of model EPC2012C.

[0054] According to some embodiments, the output of the bias circuit unit is electrically connected to the drain terminal of the enhancement-mode gallium nitride high electron mobility transistor to provide a stable and adjustable anti-interference DC power supply. The bias circuit includes a DC power supply VDC2 and a choke coil LRFC (inductance value 100nH-10μH), wherein the output of power supply VDC2 is connected to one end of the choke coil LRFC, and the other end of the choke coil LRFC is connected to the drain of the GaN device, providing an adjustable drain bias voltage of 20-50V with an adjustment accuracy of ±0.1V. Optionally, see [link to relevant documentation]. Figure 4 VDC2 and VDC4 are set to 50V, and the choke coils LRFC1 and LRFC2 are selected as 350nH.

[0055] According to some embodiments, the input terminal of the resonant network unit is electrically connected to the drain terminal of the enhancement-mode gallium nitride high electron mobility transistor, and the output terminal of the resonant network unit is electrically connected to the impedance matching circuit module 0203 to filter out harmonics and convert the pulse current into a sinusoidal voltage output to the impedance matching circuit module 0203. The resonant network includes a resonant capacitor Co (10-300pF) and a resonant inductor Lo (10-100nH), which are connected in series to form a series resonant circuit. One end of the resonant capacitor Co is connected to the drain of the GaN device, and the other end is connected to the resonant inductor Lo. The other end of the resonant inductor Lo is connected to Lx in the impedance matching circuit module 0203, thus shaping the square wave signal into a sinusoidal wave through resonance. Optionally, see [link to relevant documentation]. Figure 4 Co1 and Co2 are 170pF capacitors, Lo1 and Lo2 are 32nH inductors; Cp1 and Cp2 are 29pF capacitors, which are used to shape the square wave into an 80MHz sine wave through series resonance.

[0056] See Figure 3 and Figure 4 The impedance matching circuit module 0203 is an L-type impedance matching circuit. The input terminal of the L-type impedance matching circuit is electrically connected to the output terminal of the resonant network unit, and the output terminal of the L-type impedance matching circuit is connected to the multi-stage filter module 0204 to adjust the conjugate matching of the preceding and following stages and perform a single filtering operation. Further optionally, the impedance matching circuit module 0203 includes a series inductor Lx (1-50nH) and a parallel capacitor Cx (1-300pF). The series inductor Lx is connected in series between Lo of the resonant network and Lf of the multi-stage filter module 0204. One end of the parallel capacitor Cx is connected to the connection node between Lx and Lf, and the other end is grounded, forming an L-type matching structure to achieve 50Ω conjugate impedance conversion. Optionally, see [link to relevant documentation]. Figure 4 Lx1 and Lx2 are 21nH high-frequency inductors, and Cx1 and Cx2 are 166pF capacitors, forming an L-type matching network to realize the conversion from the output impedance of GaN device to 50Ω.

[0057] The multi-order filter module 0204 includes at least one elliptic low-pass filter. The multi-order filter module 0204 matches elliptic low-pass filters of different orders according to the system's harmonic suppression requirements to reduce higher-order harmonic interference and complete secondary filtering. Furthermore, the multi-order filter module 0204 is based on an elliptic low-pass filter design, and any order can be selected according to the system's harmonic suppression requirements (the larger the order N, the better the harmonic suppression effect). For example, see [link to example]. Figure 3A third-order elliptic low-pass filter can be selected, using an inductor Lf (52nH), capacitors Cf1 (108pF), Cf2 (17pF), and Cf3 (108pF). Lf and Cf2 are connected in parallel to form the filter unit. Cf1 is connected in parallel between Lx and ground (input side). Cf3 is located on the output side, with one end connected to the output of the filter unit and the other end connected to a 50Ω load (for single-channel output) or the input of the multi-function power combiner module 03 (for multi-channel output). For single-channel output, the output power range is 400W-1200W, adjusted according to the power supply voltage. Alternatively, see [link to relevant documentation]. Figure 4 An elliptic low-pass filter structure is adopted, with Lf1 and Lf2 selected as 52nH, Cf1, Cf3, Cf4 and Cf6 selected as 108pF, and Cf2 and Cf5 selected as 17pF.

[0058] According to some embodiments, the all-in-one power combiner module 03 includes a multi-channel LC-type balun power combiner and / or Wilkinson power combiner adapted to the number of the filter amplification paths 02, for power combining and performing three-stage filtering. Further, see... Figure 4 The multi-functional power combiner module 03 is designed based on an LC-type balun power combiner or a Wilkinson power combiner, where N ≥ 2 and is an integer. The number of N is selected according to the system power output requirements. For example, an LC-type balun power combiner is selected for two-in-one power combining, including capacitors Cb1 (29.2pF) and Cb2 (29.2pF) and inductors Lb1 (146.155nH) and Lb2 (1146.144nH). One end of Cb1 is connected to one end of Lb2, the other end of Lb2 is connected to one end of Cb2, the other end of Cb2 is connected to one end of Lb1, and the other end of Lb1 is connected to the other end of Cb1, forming a closed loop. The ground terminal is connected to the connection node of Cb1 and Lb1, and a 50Ω load is connected to the connection node of Lb2 and Cb2. The first output inductor Lf1 is connected to the junction of Cb1 and Lb2, and the second output inductor Lf2 is connected to the junction of Cb2 and Lb1, achieving in-phase synthesis of the two signals with a synthesis efficiency ≥90%. Alternatively, an LC balun structure can be used, with Cb1=Cb2=29.2pF and Lb1=Lb2=146nH. The two 680W signals are synthesized to output 1300W with a synthesis efficiency >95%. The output is filtered three times to ensure that the total harmonic rejection ratio meets the requirements of medical accelerators.

[0059] Figure 5 The diagram illustrates a solid-state power source system based on a GaN-based Class E digital pulse power amplifier, according to an example embodiment, featuring a frequency multiplier circuit topology based on a two-channel driver symmetrically driven gallium nitride device.

[0060] See Figure 5The solid-state power source system further includes a structure in which a gallium nitride-based Class E power amplifier module 0202 is driven by a dual high-frequency switch driver module 0201. The duty cycle and phase difference of the square wave signal are adjusted by the FPGA chip to achieve frequency multiplication, with a maximum operating frequency of 200MHz. The gallium nitride-based Class E power amplifier module 0202 employs two enhanced gallium nitride high electron mobility transistors (GNTs) with their sources electrically connected, and the drains of the two GNTs are alternately grounded. Furthermore, the solid-state power source system also supports an operating frequency extension mechanism. The basic operating frequency range is 1-100MHz (the intrinsic operating frequency of the FPGA chip). Frequency multiplication is achieved by adjusting the duty cycle (reduced to 25%) and phase difference (90° phase shift) of the square wave signal through the FPGA. Using two drivers to symmetrically drive the gallium nitride device (two sources connected, two drains alternately grounded), a maximum operating frequency of 200MHz can be achieved, meeting the requirements of high-frequency scenarios.

[0061] Figure 6 A flowchart of a method for a solid-state power source system according to an example embodiment is shown.

[0062] See Figure 6 The figure illustrates a method for a solid-state power source system as described in any of the preceding claims, the method comprising: In S601, a square wave signal with corresponding parameters is generated according to the system operating frequency and total power requirements, and at least one of the filtering and amplification paths is controlled to open.

[0063] According to some embodiments, firstly, the square wave signal is generated. Based on the system operating frequency (1-200MHz) and total power requirements, a square wave signal with corresponding parameters is generated by the digital pulse generation module, and the filtering and amplification path is controlled to open.

[0064] In S603, frequency multiplication is selected based on the operating frequency requirement, thereby controlling the enhanced gallium nitride high electron mobility transistor to turn on and off according to the frequency of the square wave signal.

[0065] According to some embodiments, the high-frequency switch driving module then provides a driving signal to the gate of the GaN device, selects whether to enable the frequency multiplication mode according to the operating frequency requirements, controls the GaN device to turn on / off at the square wave frequency, and outputs a sinusoidal signal shaped by resonance at the drain.

[0066] In S605, the probability of different address distributions of the technology is determined according to the mathematical model.

[0067] In S607, the impedance matching circuit module adjusts the conjugate matching of the preceding and following modules and performs a filter.

[0068] According to some embodiments, the impedance matching circuit module is then used to adjust the conjugate matching of the preceding and following stages, while simultaneously filtering the signal to suppress some higher harmonics.

[0069] In S609, at least one elliptic filter is selected for secondary filtering based on the harmonic suppression requirements.

[0070] According to some embodiments, based on the harmonic suppression requirements (second harmonic ≤ -20dB, third and higher harmonics ≤ -30dB), an Nth-order elliptic filter is selected to perform secondary filtering on the signal.

[0071] In S611, based on the number of filtering and amplification paths, a multi-channel power combiner is selected to perform power combining and three-stage filtering in order to output the combined high-frequency high-power signal to the outside.

[0072] According to some embodiments, based on the design of the filtering and amplification path described in N, power combining is performed through a multi-in-one power combiner, while simultaneously completing three filtering steps, ultimately outputting a high-frequency, high-power signal that meets the requirements.

[0073] According to some embodiments, the frequency range of the square wave signal is 1-200MHz, the second harmonic suppression ratio is better than -20dB, and the third and higher harmonic suppression ratio is better than -30dB.

[0074] According to some embodiments, the design of the present invention can also be applied to the design of medical electronic devices, which include the solid-state power source system as described above. By using GaN devices as the core switching element of the Class E digital pulse power amplifier, GaN devices have the characteristics of high electron mobility, high breakdown electric field strength and high temperature resistance. Compared with traditional silicon-based devices, they can significantly improve the efficiency of the power amplifier, with an efficiency of over 85%, while also increasing the power density. Under the same volume, the output power density increases by more than 50%, meeting the requirements of medical particle accelerators for high efficiency and high power of solid-state power sources.

[0075] According to some embodiments, the design of this invention, by adding the aforementioned gallium nitride-based Class E power amplifier module, utilizes the drain bias voltage of GaN devices to flexibly adjust the output power of the power amplifier, adapting to different load requirements and expanding the application range of the circuit. It is particularly suitable for fields such as medical particle accelerator electronic and electrical equipment where high efficiency, power density, and reliability are required. A three-stage filtering design is employed, combining an impedance matching circuit module with a multi-order filter module and an all-in-one power combiner module, achieving a second harmonic suppression ratio better than -20dB and a third and higher harmonic suppression ratio better than -30dB, thus improving particle acceleration accuracy.

[0076] According to some embodiments, the design scheme of this invention employs resonant network units and impedance transformation units. Compared with complex multi-stage matching structures, this greatly simplifies the design of the input and output matching networks, reduces design difficulty and circuit losses, improves circuit reliability, and ensures the stable operation of medical equipment. By combining intrinsic frequency operation with a frequency doubling mechanism, a wide bandwidth output of 1-200MHz is achieved, allowing adaptation to different models of medical particle accelerators without replacing core components.

[0077] It should be noted that, in specific implementations, the computing device 30 may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the device described above may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0078] Those skilled in the art will clearly understand that the technical solutions of the present invention can be implemented by means of software and / or hardware. In this specification, "unit" and "module" refer to software and / or hardware capable of independently performing or cooperating with other components to perform a specific function, wherein the hardware may be, for example, a field-programmable gate array (FPGA), an integrated circuit, etc.

[0079] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0080] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0081] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some service interface; the indirect coupling or communication connection between devices or units may be electrical or other forms.

[0082] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0083] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0084] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage device. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention.

[0085] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0086] Exemplary embodiments of the present invention have been specifically shown and described above. It should be understood that the present invention is not limited to the detailed structures, arrangements, or implementations described herein; rather, the present invention is intended to cover various modifications and equivalent arrangements contained within the spirit and scope of the appended provisions.

Claims

1. A solid-state power source system for a Class E digital pulse power amplifier based on GaN devices, characterized in that, include: The system includes a digital pulse generation module, at least one filtering and amplification path, and a multi-function power combiner module. The filtering and amplification path comprises a high-frequency switch driver module, a gallium nitride-based Class E power amplifier module, an impedance matching circuit module, and a multi-stage filter module. The input terminal of the digital pulse generator module receives signals from an external host computer, and the output terminal of the digital pulse generator module is electrically connected to the input port of the high-frequency switch drive module to generate a square wave signal with adjustable frequency, duty cycle, and amplitude. The output port of the high-frequency switch drive module is electrically connected to the gate of the enhancement-mode gallium nitride high electron mobility transistor in the gallium nitride-based Class E power amplifier module to receive a square wave signal from the digital pulse generator module, thereby responding to changes in the square wave signal to drive the gallium nitride-based Class E power amplifier module. The gallium nitride-based Class E power amplifier module receives the square wave signal, filters and shapes it into a sine wave, and then outputs it to the impedance matching circuit module. The output port of the impedance matching circuit module is electrically connected to the input port of the multi-stage filter module, and is used to adjust the conjugate matching of the preceding and following stages and perform a single filtering operation. The output port of the multi-stage filter module is electrically connected to the input port of the all-in-one power combiner module for secondary filtering; The all-in-one power combiner module is used to perform power combining and three filtering operations to output the combined high-frequency, high-power signal.

2. The solid-state power source system according to claim 1, characterized in that, The digital pulse generation module includes: an FPGA chip and a direct digital frequency synthesizer submodule, wherein, The FPGA chip receives control commands from the host computer to control the on or off signal of at least one of the filtering and amplification paths, and generates the square wave signal parameters with the required frequency, duty cycle, amplitude, and phase of the system and outputs them to the direct digital frequency synthesizer submodule. The direct digital frequency synthesizer submodule receives the square wave signal parameters from the FPGA chip and generates a corresponding square wave signal, which is then transmitted to the high-frequency switch driver module.

3. The solid-state power source system according to claim 2, characterized in that, The high-frequency switch drive module includes a driver, the input terminal of which is electrically connected to the output terminal of the direct digital frequency synthesizer submodule, and the output port of which is electrically connected to the gate of the enhancement-mode gallium nitride high electron mobility transistor in the power amplifier module, so as to receive and respond to the square wave signal, thereby outputting a drive signal to drive the power amplifier module.

4. The solid-state power source system according to claim 3, characterized in that, The gallium nitride-based Class E power amplifier module adopts a Class E power amplifier architecture, including: an enhancement-mode gallium nitride high electron mobility transistor, a bias circuit unit, and a resonant network unit, wherein... The enhanced gallium nitride high electron mobility transistor receives the drive signal from the driver and switches at high speed under the control of the drive signal to obtain a power-amplified pulse current. The output of the bias circuit unit is electrically connected to the drain terminal of the enhanced gallium nitride high electron mobility transistor to provide a stable and adjustable anti-interference DC power supply. The input terminal of the resonant network unit is electrically connected to the drain terminal of the enhanced gallium nitride high electron mobility transistor, and the output terminal of the resonant network unit is electrically connected to the impedance matching circuit module to filter out harmonics and convert the pulse current into a sinusoidal voltage output to the impedance matching circuit module.

5. The solid-state power source system according to claim 4, characterized in that, The impedance matching circuit module is an L-type impedance matching circuit. The input terminal of the L-type impedance matching circuit is electrically connected to the output terminal of the resonant network unit. The output terminal of the L-type impedance matching circuit is connected to the multi-stage filter module to adjust the conjugate matching of the preceding and following stages and perform a first-stage filtering.

6. The solid-state power source system according to claim 1, characterized in that, The multi-order filter module includes at least one elliptic low-pass filter. The multi-order filter module matches elliptic low-pass filters of different orders according to the system harmonic suppression requirements to reduce high-order harmonic interference and complete secondary filtering.

7. The solid-state power source system according to claim 1, characterized in that, The all-in-one power combiner module includes a multi-channel LC-type balun power combiner and / or Wilkinson power combiner adapted to the number of filtering and amplification paths, for power combining and completing three filtering steps.

8. The solid-state power source system according to claim 4, characterized in that, The solid-state power source system also includes: The structure employs a dual high-frequency switch driver module to drive a gallium nitride-based Class E power amplifier module. The duty cycle and phase difference of the square wave signal are adjusted via the FPGA chip to achieve frequency multiplication, with a maximum operating frequency of 200MHz. The gallium nitride-based Class E power amplifier module employs two enhanced gallium nitride high electron mobility transistors (GNTs) with their sources electrically connected to each other, and the drains of the two GNTs are alternately grounded.

9. The solid-state power source system according to claim 1, characterized in that, The square wave signal has a frequency range of 1-200MHz, a second harmonic suppression ratio better than -20dB, and a third and higher harmonic suppression ratio better than -30dB.

10. A medical electronic device, characterized in that, Includes the solid-state power source system according to any one of claims 1-9.

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