A power amplification module, control method and system thereof

Abstract

The application discloses a power amplification module, a control method and a system thereof, and belongs to the technical field of plasma generators; wherein, a multi-phase PDM step-down amplitude modulation technology is adopted in the PDM driving unit, which is used for generating two-way symmetric complementary RF driving signals through dead zone delay and logical operation on external RF driving signals; the BUCK voltage regulation unit includes a plurality of parallel BUCK circuits, which are used for reducing input DC voltage to amplitude modulation DC voltage; the RF driving unit is used for generating two-way symmetric complementary RF driving signals; the H-bridge conversion unit is used for receiving the two-way symmetric complementary RF driving signals generated by the RF driving unit and inverting the amplitude modulation DC voltage supplied by the BUCK voltage regulation unit in the previous stage into a radio frequency power signal and outputting the radio frequency power signal to a load. The power amplification module, the control method and the system thereof provided by the application realize the unity of the contradiction between high frequency response and ultra-low loss through the mutual coordination of the multi-phase PDM modulation and the class-D power amplifier topology structure.

Description

Technical Field

[0001] This application relates to the field of plasma generator technology, specifically to a power amplification module, control method, and system thereof. Background Technology

[0002] Plasma, as the fourth state of matter, possesses a variety of excellent properties such as high energy density, high chemical activity, and high conductivity. It has significant advantages in many fields such as materials processing, semiconductor manufacturing, surface treatment, environmental protection, and biomedicine, and is an important direction for the development of modern science and technology.

[0003] Plasma is primarily composed of various ionized gases, and it typically requires an external energy input to ionize the reactant gases and generate the desired plasma, i.e., a plasma generator. Plasma generators can be broadly categorized according to their excitation method and application: DC discharge plasma generators, radio frequency (RF) plasma generators, microwave plasma generators, dielectric barrier discharge plasma generators, and arc plasma generators. Among these, radio frequency (RF) plasma generators utilize radio frequency electromagnetic fields (typically in the MHz range) to ionize gases and generate plasma, and are widely used in fields such as material surface treatment and thin film deposition.

[0004] However, existing power amplification technologies have the following shortcomings:

[0005] 1. Although traditional linear power amplifiers have excellent output waveform quality, their inherent operating principle results in generally low energy conversion efficiency, with a large amount of electrical energy being converted into heat energy. This not only causes energy waste but also necessitates the use of bulky liquid cooling systems, making the systems cumbersome and complex to maintain.

[0006] 2. To achieve high-precision output control, the existing pulse width modulation (PWM) amplitude modulation technology for switching power supplies requires a significant increase in switching frequency, which limits the amplitude control accuracy and dynamic response.

[0007] 3. Existing parallel modules require complex current sharing circuits, and switching synchronization errors cause electromagnetic interference (EMI) to exceed the standard. Summary of the Invention

[0008] To address the aforementioned deficiencies in the prior art, this application provides a power amplifier module, a control method, and a system that achieve a balance between high-frequency response and ultra-low loss through the synergistic effect of multiphase PDM modulation and Class D power amplifier topology.

[0009] The technical solution is as follows:

[0010] On the one hand, a power amplifier module is provided, comprising:

[0011] The PDM drive unit adopts multi-phase PDM step-down amplitude modulation technology, which controls the output voltage amplitude by adjusting the PDM duty cycle. It is used to generate two symmetrical and complementary RF drive signals from the external RF drive signal through dead-time delay and logic operation, and drive the subsequent BUCK voltage regulation unit.

[0012] The BUCK voltage regulator unit is used to step down the input DC voltage to an amplitude-modulated DC voltage.

[0013] The RF drive unit is used to receive external RF drive signals and RF drive signals with dead-time delay, and to perform logical operations on the two RF drive signals to generate two symmetrical and complementary RF drive signals.

[0014] The H-bridge converter unit is used to receive two symmetrical and complementary RF drive signals generated by the RF drive unit and invert the amplitude-modulated DC voltage supplied by the BUCK voltage regulation unit in the previous stage into an RF power signal for output to the load.

[0015] The control unit is used to monitor the status of each subsystem of the power amplifier module;

[0016] The PDM driver unit, BUCK voltage regulation unit, RF driver unit, and H-bridge converter unit constitute the power link of the power amplifier module.

[0017] Furthermore, the power amplifier module is a Class D power amplifier topology, and the SiC MOSFET field-effect transistors in the BUCK voltage regulation unit and the H-bridge converter unit are all switching transistors.

[0018] Furthermore, the total loss of the SiC MOSFET switch is:

[0019]

[0020]

[0021] In the formula, Total loss, For conduction loss, Switching losses, For capacitor losses, Reverse recovery loss of body diode , For drive circuit losses, This represents the effective value of the current flowing through the SiCMOSFET switch when it is turned on. For conduction resistance, This refers to the drain-source voltage of the SiC MOSFET switch. It is the peak current. For switching frequency, Output capacitor, To reverse the charge, To reverse the charge, This is the gate-source voltage of the SiC MOSFET switch.

[0022] Furthermore, the PDM driving unit includes a CMOS driving unit, which is used to convert the received external PDM signal into a driving signal for directly driving the BUCK unit.

[0023] Furthermore, the PDM drive unit receives external PDM control signals and phase-shifts its amplitude control signals with N channels. After comparing the triangular wave signals, N PDM control signals are generated, among which, P is an integer. .

[0024] Furthermore, an externally supplied 0.1MHz-15MHz first RF drive signal enters the PDM drive unit, and after a dead-time delay, a second RF drive signal is generated. Then, the first and second RF drive signals pass through a logic operation circuit to generate a third and a fourth RF drive signal. The third and fourth RF drive signals are symmetrical and complementary square wave signals.

[0025] Furthermore, it also includes a power detection unit, which is used to detect the power, voltage, and current signals output by each stage of the power amplifier module's subsystems and then transmit them to the control unit.

[0026] Furthermore, it also includes a communication unit for communicating with the outside world.

[0027] On the other hand, a control method for a power amplifier module is provided, applied to the aforementioned power amplifier module, the control method comprising the following steps:

[0028] Generate N mutually phase-shifted paths The triangular wave signal, in which, P is an integer. N represents the number of PDM phases within a single power amplifier module;

[0029] After comparing the amplitude control signal with each triangular wave signal, N PDM signals are generated.

[0030] The output voltage amplitude of the PDM drive unit is adjusted by the duty cycle D. Assuming the drive frequency of the drive signal required for single-phase PDM step-down amplitude modulation is... f Duty cycle is D If the parameters of the N-phase PDM step-down amplitude modulation are consistent with those of the single-phase PDM step-down amplitude modulation, then the required drive frequency of the drive signal is: f / N, duty cycle isND .

[0031] On the other hand, a power amplification system is provided, comprising:

[0032] At least two power amplifier modules as described above;

[0033] The filtering and combining network is used to filter and combine the RF signals output from each power amplifier module;

[0034] The control unit is used to control the generation of out-of-phase drive signals from the PDM drive signals between each power amplifier module.

[0035] M power amplifier modules are connected in parallel. The output of each power amplifier module is connected to the input of a filter combining network. The filter combining network converts the square wave pulse signal into a radio frequency sine wave signal. The phase difference between the PDM drive signals of adjacent power amplifier modules is... , where N is the number of PDM phases in a single power amplifier module.

[0036] The technical solution includes at least the following technical effects:

[0037] 1. The use of multiphase PDM technology increases the sampling frequency and reduces the size of subsequent filter components.

[0038] 2. Modular design allows for easy connection of multiple modules in series and parallel to improve overall output power. The modular design also supports online replacement.

[0039] 3. Adopting a Class D power amplifier topology, the efficiency of the power amplifier module is improved to over 90%, with high power density and a single module capable of outputting up to 4kW.

[0040] 4. The multiphase PDM and Class D power amplifier topology work together to achieve a balance between high-frequency response and ultra-low loss.

[0041] 5. The PDM drive unit receives external PDM control signals and generates N mutually phase-shifted PDM drive signals. The phase-shifted drive suppresses electromagnetic interference.

[0042] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0043] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0044] Figure 1 A schematic block diagram of a power amplifier module provided in a preferred embodiment;

[0045] Figure 2 A schematic block diagram of the power link in a power amplifier module provided in a preferred embodiment;

[0046] Figure 3 A schematic diagram of a PDM drive unit in a power amplifier module is provided as a preferred embodiment;

[0047] Figure 4 A block diagram of the control circuit principle of a three-phase PDM drive unit provided in a preferred embodiment;

[0048] Figure 5 Simulation results of the control circuit principle of the three-phase PDM drive unit provided in a preferred embodiment;

[0049] Figure 6 A circuit block diagram of an H-bridge converter unit provided in a preferred embodiment;

[0050] Figure 7 Thermal simulation analysis diagram of the H-bridge switch transistor of the H-bridge converter unit provided in a preferred embodiment;

[0051] Figure 8 is a physical model diagram of a power amplifier module provided in a preferred embodiment;

[0052] Figure 9 shows the measured output of the power amplifier module provided in a preferred embodiment;

[0053] Figure 10 is a block diagram of the power amplification system synthesis principle provided in a preferred embodiment;

[0054] Explanation of reference numerals in the attached figures:

[0055] 1. PDM drive unit; 2. BUCK voltage regulation unit; 3. H-bridge conversion unit; 4. RF drive unit; 5. RF drive signal generation unit; 6. Power detection unit; 7. Control unit; 8. Communication unit; 9. Shielding layer; 10. H-bridge heat sink. Detailed Implementation

[0056] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0057] A preferred embodiment provides a power amplifier module that differs from traditional linear power amplifiers. It employs a Class D power amplifier mode, operating in a switching state with losses only occurring during the switching instant, achieving an energy conversion efficiency of over 90%. This power amplifier module utilizes high-precision pulse width modulation (PDM) distribution technology with multi-phase voltage regulation to achieve high-speed, miniaturized, and high-precision control of the output amplitude. The power amplifier module has an output frequency of 0.1MHz-15MHz, an average output power of 5kW, and a peak output power of 15kW, exhibiting high power density. Its modular design facilitates system expansion and maintenance. Furthermore, it can be configured into a power amplifier system through a simple series-parallel structure supplemented by a filter synthesis network, easily achieving power output in the hundreds of kW to MW range.

[0058] This application discloses a power amplifier module, a device for generating a special power supply for cryogenic plasma, which provides the energy required for the plasma generating device and supplies the front-end electrical power for plasma applications.

[0059] As attached Figure 1 As shown, a preferred embodiment of the power amplifier module includes a PDM driver unit 1, a BUCK voltage regulation unit 2, an RF driver unit 4, an H-bridge converter unit 3, a power detection unit 6, a control unit 7, a communication unit 8, etc.

[0060] PDM driver unit 1 employs multiphase PDM buck amplitude modulation technology, controlling the output voltage amplitude by adjusting the PDM duty cycle. It generates two symmetrical and complementary RF drive signals from the external RF drive signal through dead-time delay and logic operations, driving the subsequent BUCK voltage regulation unit 2. An external 0.1MHz-15MHz first RF drive signal (RF signal) enters PDM driver unit 1, undergoes dead-time delay to generate a second RF drive signal, and then the first and second RF drive signals pass through a logic operation circuit to generate a third and fourth RF drive signal. The third and fourth RF drive signals are symmetrical and complementary square wave signals.

[0061] PDM driver unit 1 includes a CMOS driver unit, which mainly converts the external PDM signal received by the power amplifier module into a drive signal for directly driving the switching transistor of the BUCK driver unit.

[0062] The BUCK voltage regulating unit 2 includes several parallel BUCK circuits, which mainly step down and modulate the externally supplied DC voltage signal according to the settings to generate the required DC voltage amplitude.

[0063] The RF drive unit 4 is mainly used to receive externally supplied RF drive signals and RF drive signals with dead-time delay, and then perform logical operations on these two RF drive signals to generate two symmetrical and complementary RF drive signals.

[0064] H-bridge converter 3 is mainly used to receive two symmetrical and complementary RF drive signals generated by RF drive unit 4, and invert the amplitude-modulated DC voltage supplied by the front-end BUCK voltage regulation unit 2 into an RF power signal to generate the RF power signal required to drive the plasma. The signal is then output to the load, generating an RF signal of 0.1MHz-15MHz at both ends of the load to drive the plasma generation.

[0065] Control unit 7 is a microcontroller unit that mainly performs functions such as status reading, logic control, external interlock control, and remote communication for all subsystems of the power amplifier module, ensuring the reliable operation of the system.

[0066] The power detection unit 6 detects the power, voltage, and current signals output from each stage of the power amplifier module's subsystems and then transmits them to the control unit 7. The power detection unit is used for real-time monitoring of anomalies.

[0067] Communication unit 8 is used for communication connections with external systems.

[0068] like Figure 2 As shown, PDM drive unit 1, BUCK voltage regulation unit 2, RF drive unit 4, and H-bridge conversion unit 3 constitute the power link of the power amplifier module.

[0069] The power link of the power amplifier module mainly consists of N BUCK voltage regulation units and H-bridge conversion units and their driving units. N is the number of phases in the multiphase PDM amplitude modulation. Theoretically, the larger N is, the more precise the multiphase PDM amplitude modulation and the greater the transmission power. Considering the size of the power amplifier module and the power limitation of the subsequent H-bridge, in this embodiment, N is an integer between 3 and 6, and can be selected as 3, 4, 5, or 6. The frequency of each phase is generally taken to be between 100kHz and 500kHz. After multiphase modulation, the BUCK switching frequency can be increased by N times, which greatly reduces the inductance of the subsequent filter and reduces the switching noise of the BUCK. At the same frequency, the power consumption of a single tube is also reduced.

[0070] In this embodiment, the power amplifier module uses a Class D amplifier. The core of the BUCK voltage regulation unit and H-bridge converter unit within the module, the Silicon Carbide Metal-Oxide-Semiconductor Field-Effect Transistor (SiC MOSFET), operates in a switching state; that is, the SiC MOSFET is a switching transistor. Theoretically, if this device is an ideal switch—with zero on-resistance, infinite off-resistance, no parasitic parameters, and zero switching time—then the power amplifier module's losses will be zero, and all the energy provided by the DC power supply will be transferred to the load, achieving 100% theoretical efficiency. However, in actual operation, SiC MOSFETs are not ideal switches and will generate some power loss. Therefore, to maximize the output power of the power amplifier module and increase power density, the power loss generated by the SiC MOSFET should be minimized as much as possible.

[0071] The losses of SiC MOSFET field-effect transistors include the following: SiC MOSFETs have on-resistance during conduction, resulting in conduction losses; the switching from on to off or vice versa is not instantaneous, but involves a delay during which the voltage and current of the SiC MOSFET switch are not zero, resulting in switching losses; the parasitic output capacitance of the SiC MOSFET switch undergoes charging and discharging during switching, and this energy consumption results in output capacitance losses; the body diode of the SiC MOSFET requires a certain amount of time to recover its blocking capability under reverse voltage, resulting in body diode reverse recovery losses; and the gate drive circuit of the SiC MOSFET switch charges and discharges its parasitic input capacitance, and the charging and discharging of the gate charge results in drive circuit losses.

[0072] During the turn-on process, SiC MOSFET switches experience a certain amount of conduction loss due to the on-resistance. ,as follows:

[0073]

[0074] In the formula, This represents the effective value of the current flowing through the SiC MOSFET when it is turned on.

[0075] This indicates the on-resistance The smaller the value, the lower the conduction loss, and the higher the output efficiency of the power amplifier module.

[0076] When a SiC MOSFET switch transitions from the on-state to the off-state or vice versa, the transition is not instantaneous but involves a certain delay. During this delay, both the voltage and current of the SiC MOSFET are not zero, resulting in switching losses. To simplify the analysis, assume a rise time of... and descent time Equal, use the symbol This refers to the switching losses caused by switching state transitions during a complete signal cycle. for:

[0077]

[0078] In the formula, This is the drain-source voltage of the SiC MOSFET. It is the peak current. This represents the switching frequency.

[0079] This indicates the switching frequency The smaller the rise time and descent time The shorter the length, the lower the conduction loss, and the higher the output efficiency of the power amplifier module.

[0080] Parasitic output capacitance of SiC MOSFET During the switching process, there is a charging and discharging process, and the consumption of this energy will result in a certain output capacitor loss. ,as follows:

[0081]

[0082] This indicates the switching frequency The smaller the output capacitor The smaller the value, the lower the conduction loss, and the higher the output efficiency of the power amplifier module.

[0083] The body diode of a SiC MOSFET requires a certain amount of time to recover its blocking capability under reverse voltage and to recover its charge under reverse voltage. The charging and discharging of the diode will generate a certain reverse recovery loss. ,as follows:

[0084]

[0085] This indicates that the lower the switching frequency and the smaller the reverse recovery charge, the lower the conduction loss and the higher the output efficiency of the power amplifier module.

[0086] The gate drive circuit of a SiC MOSFET charges and discharges its parasitic input capacitance, and the gate charge... Charging and discharging will generate certain drive circuit losses. ,as follows

[0087]

[0088] In the formula, This is the gate-source voltage of the SiC MOSFET.

[0089] This indicates the switching frequency The smaller the reverse recovery charge The smaller the value, the lower the conduction loss, and the higher the output efficiency of the power amplifier module.

[0090] Therefore, the total loss of a SiC MOSFET is:

[0091]

[0092]

[0093] In the formula, Total loss, For conduction loss, Switching losses, For capacitor losses, Reverse recovery loss of body diode , For drive circuit losses, This represents the effective value of the current flowing through the SiCMOSFET switch when it is turned on. For conduction resistance, This refers to the drain-source voltage of the SiC MOSFET switch. It is the peak current. For switching frequency, Output capacitor, To reverse the charge, To reverse the charge, This is the gate-source voltage of the SiC MOSFET switch.

[0094] Therefore, when selecting SiC MOSFETs, switching transistors with small parasitic parameters should be chosen as much as possible to ensure the output efficiency of the power amplifier module and reduce the switching frequency.

[0095] In this embodiment, as Figure 2 and Figure 3As shown, the PDM driver unit 1 and the BUCK voltage regulation unit 2 are among the core components of the power amplifier module. The PDM driver unit 1 employs multiphase PDM step-down amplitude modulation technology, controlling the output voltage amplitude by adjusting the PDM duty cycle. The higher the duty cycle, the higher the supply voltage of the module, and consequently, the higher the overall output power of the module; conversely, the lower the duty cycle, the lower the output power. An externally supplied 0.1MHz-15MHz first RF drive signal enters the PDM driver unit, undergoes dead-time delay (i.e., a delay circuit used to generate dead time) to generate a second RF drive signal, and then the first and second RF drive signals pass through a logic operation circuit to generate a third and fourth RF drive signal. The third and fourth RF drive signals are symmetrical and complementary square wave signals, which enter the H-bridge converter unit through the BUCK voltage regulation unit to drive the H-bridge converter unit to generate RF signal output.

[0096] PDM drive unit 1 is a multiphase PDM step-down amplitude modulation unit. The required PDM control signal is provided externally by the power amplifier module. Its amplitude control signal is compared with N mutually phase-shifted triangular wave signals of phase P° to generate N PDM signals, namely PDM1-PDMN, realizing multiphase PDM control of the amplitude signal. The generated signals follow a phase-shifted superposition relationship. Where P = 360 / N, P is an integer, 2... N is an integer, which can be selected as 2, 3, 4, 5, 6, 8, 9, or 10. In this embodiment, N is an integer between 3 and 6, and can be selected as 3, 4, 5, or 6.

[0097] Assuming the driving frequency of the drive signal required for single-phase PDM buck amplitude modulation is f, and the duty cycle is D, if the parameters of N-phase PDM buck amplitude modulation are consistent with those of single-phase PDM buck amplitude modulation, then the required driving frequency of the drive signal is f / N, and the duty cycle is ND. This is equivalent to increasing the sampling frequency of amplitude control, which is more conducive to the miniaturization of subsequent low-pass filters. Similarly, multi-phase PDM buck amplitude modulation can effectively increase the sampling rate of the amplitude control circuit without increasing the operating frequency of the buck switch, thereby possessing better amplitude control capability, faster response speed, and reducing the power loss of SiC MOSFETs.

[0098] like Figure 4 The block diagram of the control circuit of the three-phase PDM drive unit 1 shown is shown. The three-phase PDM drive unit 1 controls the amplitude control signal with three mutually phase-shifted signals. The triangular wave signals are compared to generate three PDM drive signals.

[0099] Based on the above analysis, the three-phase PDM control circuit was simulated and analyzed using SPICE modeling technology, as shown in Figure 5. Taking a sinusoidal signal as the amplitude control signal as an example, it was compared with three triangular wave signals with a 120° phase shift, generating three PDM drive signals. The drive pulse width is proportional to the amplitude of the sinusoidal signal.

[0100] The above verifies that the PDM drive unit effectively reduces the power loss of a single SiC MOSFET, increases the sampling frequency of amplitude control, reduces the size of the subsequent filter circuit, has a faster response speed, and improves the high accuracy of amplitude control.

[0101] RF drive unit 4 and H-bridge converter unit 3 are also core modules of the power amplifier module.

[0102] The RF drive signal of RF drive unit 4 is generated by dead-time delay and logic operation from one 0.1MHz-15MHz radio frequency signal to form two symmetrical and complementary square wave RF drive signals.

[0103] H-bridge converter 3 includes 4 SiC MOSFET switches. The 4 SiC MOSFET switches and their driving circuits constitute the H-bridge power topology. Two symmetrical and complementary square wave RF driving signals generated by RF driving unit 4 are input to H-bridge converter 3. The 4 SiC MOSFET switches are turned on in a cross-sequential manner, and the direction of the current flowing through the load changes accordingly, generating 0.1MHz-15MHz radio frequency signals at both ends of the load to drive the generation of plasma.

[0104] like Figure 6 As shown, the RF drive signal is generated from a single 0.1MHz-15MHz RF signal, producing two symmetrical and complementary square wave RF drive signals: the first RF drive signal and the second RF drive signal. A dead time of tens of nanoseconds is maintained between these two drive signals to prevent simultaneous conduction of the upper and lower bridge arm switches, which could damage the circuit. When the first RF drive signal is high, the second RF drive signal is low, the first switch Q1 and the third switch Q3 are turned on, and the second switch Q2 and the fourth switch Q4 are turned off, resulting in a positive output load on the left and a negative output load on the right. Conversely, when the second RF drive signal is high, the first RF drive signal is low, the second switch Q2 and the fourth switch Q4 are turned on, and the first switch Q1 and the third switch Q3 are turned off, resulting in a negative output load on the left and a positive output load on the right. Thus, the four SiC MOSFET switches of the H-bridge switching circuit conduct sequentially and alternately, changing the direction of the current flowing through the load and generating a 0.1MHz-15MHz RF signal across the load to drive plasma generation.

[0105] As can be seen from the above analysis, a large part of the power loss of SiC MOSFET switches comes from the switching losses generated during the turn-on and turn-off process. These losses are directly related to the switching frequency and parasitic parameters. The higher the switching frequency, the greater the loss. Therefore, the parasitic parameters of the four SiC MOSFET switches in the H-bridge converter should be as small as possible.

[0106] In a preferred embodiment, a rated parameter is used. , , , , The SiC MOSFET is used as the switching transistor in the H-bridge switching unit. The parameters of this SiC MOSFET switching transistor are as follows: , , , It is fast enough for the Class D power amplifier module required in this application.

[0107] Power losses in the power amplifier module are dissipated as heat within the power devices. Therefore, an efficient heatsink and cooling system are essential to keep the junction temperature within acceptable limits. Thermal analysis was performed based on the parameters of the SiC MOSFET switch. The heatsink has a thermal resistance of 0.024 K / W, and forced air cooling provides an airflow of 354.7 CFM. Preliminary simulation analysis shows that, as... Figure 7 As shown, the maximum temperature of the radiator is 70°C. The high-efficiency power amplification enables the system to achieve high power density and eliminates the need for liquid cooling, which greatly simplifies the design of the cooling system and reduces the overall system weight.

[0108] like Figure 8 The diagram shows a physical model of the power amplifier module, which includes a PDM driver unit 1, a BUCK voltage regulation unit 4, a shielding layer 9, and an H-bridge heatsink 10. The entire power amplifier module utilizes forced air cooling, is small in size, highly integrated, and has a high power density. The entire module weighs only 2.3kg. It features gold-finger connections and uses long and short fingers for hot-swapping. Furthermore, shielding plates are designed on both sides of the power amplifier module, achieving good electromagnetic compatibility and facilitating the expansion and maintenance of the power amplifier module.

[0109] Actual output testing was conducted on the power amplifier module according to the embodiments of this application. Taking a 50Ω load, DC 400V without amplitude modulation, and an RF drive frequency of 2MHz as an example, the actual test results are shown in Figure 9. This power amplifier module can normally output a ±400V square wave pulse signal, with a rise time of 43.5ns and a fall time of 52.3ns, meeting the electrical parameter requirements for plasma generation. Adding a filter synthesis network after the power amplifier module can filter the output waveform into a standard RF sine wave signal.

[0110] The power amplifier module of this application adopts a modular design, with a compact and simple structure, high power density, and facilitates system expansion and maintenance. It can also form a power amplifier system through a simple series-parallel connection structure supplemented by a filter synthesis network, easily achieving power output from hundreds of kW to MW levels. Simultaneously, the PDM drive signals between the power amplifier modules can also generate out-of-phase drive, consistent with the control principle of the multi-phase PDM drive unit circuit analyzed above. This further reduces the losses of the amplitude regulation switching transistors, achieving precise amplitude control.

[0111] A preferred embodiment provides a control method for a power amplifier module. Using the power amplifier module, the control method includes the following steps:

[0112] Generate N mutually phase-shifted paths The triangular wave signal, in which, P is an integer. N represents the number of PDM phases within a single power amplifier module;

[0113] After comparing the amplitude control signal with each triangular wave signal, N PDM signals are generated.

[0114] The output voltage amplitude of the PDM drive unit is adjusted by the duty cycle D.

[0115] like Figure 10 As shown, a preferred embodiment provides a power amplification system, comprising:

[0116] At least two power amplifier modules as described above;

[0117] The filtering and combining network is used to filter and combine the RF signals output from each power amplifier module;

[0118] The control unit is used to control the generation of out-of-phase drive signals from the PDM drive signals between each power amplifier module.

[0119] M power amplifier modules are connected in parallel. The output of each power amplifier module is connected to the input of a filter combining network. The filter combining network converts the square wave pulse signal into a radio frequency sine wave signal. The phase difference between the PDM drive signals of adjacent power amplifier modules is... , where N is the number of PDM phases in a single power amplifier module.

[0120] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

Claims

1. A power amplification module, characterized by, The power amplifier module adopts a Class D power amplifier topology, and the power amplifier module includes: The PDM drive unit controls the output voltage amplitude by adjusting the duty cycle of the PDM drive signal. It is used to convert the received external PDM drive signal into a PWM signal that is directly used to drive the switching transistor, so as to drive the subsequent multi-channel parallel BUCK voltage regulation unit. The BUCK voltage regulation unit includes several parallel BUCK circuits. After receiving the PWM drive signal output by the PDM drive unit, it modulates the input DC voltage to the required amplitude DC voltage. The DC voltage signal is dynamically modulated in real time according to the PDM signal. The RF drive unit is used to convert the external RF drive signal into two symmetrical and complementary PWM drive signals with dead time delay after passing through the logic operation circuit. The PWM drive signals are used to drive the subsequent Class D power amplifier topology. After receiving the dual symmetrical PWM drive signals, the Class D power amplifier topology will convert the amplitude modulation voltage signal output by the multi-parallel BUCK circuit of the front stage into the target RF power signal. The H-bridge converter unit is used to receive two symmetrical and complementary PWM drive signals generated by the RF drive unit and invert the amplitude-modulated DC voltage supplied by the multi-parallel BUCK voltage regulation unit in the previous stage into an RF power signal output to the load. The control unit is used to monitor the status of each subsystem of the power amplifier module; The PDM driver unit, BUCK voltage regulation unit, RF driver unit, and H-bridge converter unit constitute the power link of the power amplifier module.

2. The power amplification module of claim 1, wherein, The power amplifier module adopts a Class D amplifier structure, and the SiC MOSFET field-effect transistors in the BUCK voltage regulation unit and H-bridge conversion unit are all SiC MOSFET switching transistors.

3. The power amplification module of claim 2, wherein, The total loss of the SiC MOSFET switch is: In the formula, Total loss, For conduction loss, Switching losses, For capacitor losses, Reverse recovery loss of body diode , For drive circuit losses, This represents the effective value of the current flowing through the SiC MOSFET switch when it is turned on. For conduction resistance, This refers to the drain-source voltage of the SiC MOSFET switch. It is the peak current. For switching frequency, Output capacitor, To reverse the charge, To reverse the charge, This represents the gate-source voltage of the SiCMOSFET switch.

4. The power amplifier module according to claim 1, characterized in that, The PDM driving unit includes a CMOS driving unit, which is used to convert the received external PDM signal into a PWM driving signal for directly driving the multi-channel parallel BUCK unit.

5. The power amplifier module according to claim 4, characterized in that, The PDM drive unit receives external PDM control signals and phase-shifts its amplitude control signals with N mutually offset PDM signals. After comparing the triangular wave signals, N PDM control signals are generated, where P = 360 / N, and P is an integer. .

6. The power amplification module of claim 1, wherein, An externally supplied 0.1MHz-15MHz first RF drive signal enters the RF drive unit, and after a dead-time delay, a second RF drive signal is generated. Then, the first and second RF drive signals pass through a logic operation circuit to generate a third and a fourth RF drive signal. The third and fourth RF drive signals are symmetrical and complementary PWM drive signals.

7. The power amplification module of any of claims 1-6, wherein, It also includes a power detection unit, which is used to detect the power, voltage, and current signals output by each stage of the power amplifier module's subsystems and then transmit them to the control unit.

8. The power amplification module of any of claims 1-6, wherein, It also includes a communication unit for communicating with the outside world.

9. A control method of a power amplification module, applied to the power amplification module of claim 1, characterized in that, include: Generate N mutually phase-shifted paths The triangular wave signal, in which, P is an integer. N represents the number of PDM phases within a single power amplifier module; After comparing the amplitude control signal with each triangular wave signal, N PDM signals are generated. The output voltage amplitude of the PDM drive unit is adjusted by the duty cycle D.

10. A power amplification system, characterized by, include: At least two power amplifier modules as described in claim 1; The filtering and combining network is used to filter and combine the RF signals output from each power amplifier module; The control unit is used to control the generation of out-of-phase drive signals from the PDM drive signals between each power amplifier module. M power amplifier modules are connected in parallel. The output of each power amplifier module is connected to the input of a filter combining network. The filter combining network converts the square wave pulse signal into a radio frequency sine wave signal. The phase difference between the PDM drive signals of adjacent power amplifier modules is... Where N is the number of PDM phases in a single power amplifier module.

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