An output matching detection device and method for a radio frequency amplifier system adapting to complex dynamic impedance

Abstract

The present invention discloses an output matching detection device and method for a radio frequency amplifier system adapting to complex dynamic impedance, comprising: the device comprising: a shell, with an inner conductor and a radio frequency connector provided at both ends of the shell, the inner conductor and the radio frequency connector partially extending into the shell and being connected to each other; an inner conductor tube provided in the shell, the inner conductor and the inner cavity of the shell forming a coaxial transmission line for transmitting high-power radio frequency energy; a sampling plate provided on the shell, with copper screws provided on the sampling plate for connecting the sampling plate with the inner conductor tube and the inner conductor to collect voltage signals; an inductor provided on the sampling plate for coupling current signals through the inner cavity of the shell; a coupling plate provided on the side of the shell, comprising a coupling rod mounting plate connected to the shell and a coupling rod connected to the coupling rod mounting plate, for forming a coupling structure with the inner conductor to realize radio frequency coupling sampling function.

Description

Technical Field

[0001] The present invention relates to an output matching detection device and method, in particular to an output matching detection device and method for a radio frequency amplifier system adapting to complex dynamic impedance. Background Art

[0002] When RF systems are used in industrial equipment, particle accelerators and other industries, there is a practical need to adapt to complex dynamic load impedances.

[0003] These load impedances have a large dynamic range and change rapidly, which places stringent requirements on the RF system, especially the output matching of the RF amplifier.

[0004] The main purpose of output impedance matching of RF amplifier is to match the output impedance of the amplifier with the load impedance by reasonably adjusting the load equivalent impedance, so as to ensure that the power can be transmitted from the RF amplifier to the load as effectively as possible.

[0005] For example, the output impedance of a general RF amplifier is 50 ohms. If the load impedance is not equal to 50 ohms, some of the energy will be reflected back to the RF amplifier, which may damage the RF amplifier. At the same time, the RF energy obtained by the load will be reduced, resulting in waste of RF energy. Therefore, it is particularly important for the entire system to adjust the load impedance in real time to match it to the amplifier impedance.

[0006] By detecting the output matching of the RF amplifier, it can be used as a basis for real-time adjustment of the load matching network impedance, thereby ensuring that the RF energy can be used most effectively by the load.

[0007] Therefore, how to detect the values of the incident voltage and the reflected voltage and provide feedback control measurement signals to achieve output matching of the load is a problem that needs to be solved at present. Summary of the Invention

[0008] Purpose of the invention: To provide an output matching detection device and method for a radio frequency amplifier system that is adaptable to complex dynamic impedance, so as to solve the above-mentioned problems existing in the prior art.

[0009] Technical solution: An output matching detection device for a radio frequency amplifier system adapting to complex dynamic impedance, comprising:

[0010] A housing, with an inner conductor and a radio frequency connector provided at both ends of the housing, the inner conductor and the radio frequency connector partially extending into the housing and being interconnected; an inner conductor tube provided within the housing, the inner conductor and the inner cavity of the housing forming a coaxial transmission line for transmitting high-power radio frequency energy;

[0011] A sampling plate is provided on the housing, and copper screws are provided on the sampling plate for connecting the sampling plate with the inner conductor tube and the inner conductor to collect voltage signals;

[0012] The sampling board is also provided with an inductor for coupling the current signal through the inner cavity of the shell;

[0013] The coupling plate is arranged on the side of the shell and comprises a coupling rod mounting plate connected to the shell and a coupling rod connected to the coupling rod mounting plate. It is used to form a coupling structure with the inner conductor to realize the RF coupling sampling function.

[0014] In a further embodiment, a cover plate is further provided on the outer side of the coupling plate;

[0015] The shell is further provided with an insulating cover at one end of the inner conductor.

[0016] In a further embodiment, the sampling board has a built-in current sampling circuit and a voltage sampling circuit;

[0017] The voltage sampling circuit includes high-voltage capacitors C1 and C2 that form a capacitive voltage divider;

[0018] The present invention discloses an output matching detection device and method for a radio frequency amplifier system adapting to complex dynamic impedance. The present invention designs a detection device to transmit the output of the radio frequency amplifier to a load through the detection device;

[0019] Part of the device uses inductive coupling to sample the incident and reflected power, which is then detected by a diode and sent to a multiplier for self-multiplication. After that, it passes through a conditioning circuit to complete the incident power and reflected power amplitude calibration output, making it convenient for the control system to perform power display linear fitting and subsequent excessive reflection protection processing;

[0020] The other part completes the RF current and RF voltage sampling through inductive coupling and capacitive coupling, and then splits them into two paths after filtering;

[0021] One of the RF current and RF voltage is phase-compared to output the RF current and voltage phase difference for the control system to perform subsequent load impedance adjustment. If the load impedance is purely resistive, the RF voltage and current phase difference is 0. If the load impedance is inductive, the current phase lags the voltage phase. If the load impedance is capacitive, the current phase leads the voltage phase.

[0022] The other RF current and RF voltage are detected by diodes and then added and subtracted respectively, and finally divided to obtain the reflection coefficient.

[0023] The control system can perform standing wave ratio protection and corresponding load adjustment according to the reflection coefficient, perform coarse adjustment of load impedance according to the reflection coefficient, and complete fine adjustment of load impedance according to the phase difference.

[0024] At the same time, all detection circuits are hardware analog circuits, which have the advantages of high sensitivity, fast response speed, and structural integration.

[0025] Compared with traditional directional couplers, it can achieve high-precision isolation between incident and reflected signals that is easier to adjust, thus avoiding the influence of isolation on precise measurement that is inevitable in traditional directional couplers.

[0026] Based on this method, the incident voltage and reflected voltage values can be obtained with higher precision, providing feedback control measurement signals for achieving output matching of the load.

[0027] An output matching detection method for a radio frequency amplifier system adapting to complex dynamic impedances comprises:

[0028] Step 1: Assume the incident voltage is U f , the reflected voltage is U r , the characteristic impedance of the transmission line is Z0, the angular frequency is ω, and the transmission speed of the electromagnetic wave in the inner conductor is V;

[0029] When the length of the feeder from the output of the RF amplifier to the RF current and RF voltage sampling coil is X meters, the voltage U at point X is X , current I X The signals are:

[0030]

[0031] Where, j represents the imaginary part;

[0032] Step 2: Assume that the mutual inductance between the inner core of the feed tube and the inductor T is M, and the inductance of the inductor T is L. When there is a high-frequency current I on the inner core of the feed tube X When the current flows through, the induced electromotive force generated on the inductor T is e, which is:

[0033] e=jωMI X =(jωL+jωC / / R)I1

[0034] This electromotive force e forms a high-frequency current I1 in the network composed of L, R and C, where R represents resistance and C represents capacitance.

[0035] Step 3. Select jωL+jωC / / R, then:

[0036]

[0037] The voltage signal output by current sampling is:

[0038]

[0039] Step 4: Analyze the voltage U obtained on the high-voltage capacitor C2 c_pickup ;

[0040]

[0041] Since L and high-voltage capacitors C1 and C2 are adjustable design parameters, we can know that:

[0042]

[0043] Step 5: Adjust the parameters so that k1=k2, then:

[0044]

[0045]

[0046] U f_pickup Represents the forward power sampling, U r_pickup Indicates the sampling of reverse power.

[0047] Beneficial Effects: The present invention discloses an output matching detection device and method for a radio frequency amplifier system adapting to complex dynamic impedance. Compared with a traditional directional coupler, the device and method achieve high isolation between incident and reflected signals that is easier to adjust, and avoids the influence of isolation on precise measurement that is inevitable in traditional directional couplers.

[0048] Based on this method, the incident voltage and reflected voltage values can be obtained with higher precision, providing feedback control measurement signals for achieving output matching of the load. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is the principle block diagram of the RF amplifier system.

[0050] Figure 2 The diagram is a schematic diagram of a method and device for detecting output matching of a radio frequency amplifier.

[0051] Figure 3 It is a schematic structural diagram of the detection device of the present invention.

[0052] Figure 4 It is a cross-sectional schematic diagram of the detection device of the present invention.

[0053] Figure 5 2 is a schematic cross-sectional view of the detection device of the present invention.

[0054] Figure 6 3 is a schematic cross-sectional view of the detection device of the present invention.

[0055] Figure 7 Schematic diagram of the coupling plate of the detection device of the present invention.

[0056] Figure 8 It is a schematic diagram of the inner conductor and inner conductor tube of the detection device of the present invention.

[0057] Figure 9 Schematic diagram of the current sampling circuit of the present invention.

[0058] Figure 10 It is a schematic diagram of the voltage sampling circuit of the present invention.

[0059] The accompanying drawings are:

[0060] 1. RF connector; 2. Sampling plate; 3. Housing; 4. Copper screws; 5. Inner conductor; 6. Insulation cover; 7. Cover plate; 8. Coupling plate; 81. Coupling rod mounting plate; 82. Coupling rod; 9. Inner conductor tube; 10. Inductor. DETAILED DESCRIPTION

[0061] The present application relates to an output matching detection device and method for a radio frequency amplifier system adapting to complex dynamic impedance, which is explained in detail below through specific implementation methods.

[0062] An output matching detection device for a radio frequency amplifier system adapting to complex dynamic impedance, comprising:

[0063] A housing 3 is provided with an inner conductor 5 and a radio frequency connector 1 at both ends of the housing 3. The inner conductor 5 and the radio frequency connector 1 partially extend into the housing 3 and are interconnected. An inner conductor tube 9 is provided in the housing 3. The inner conductor 5 and the inner cavity of the housing 3 form a coaxial transmission line for transmitting high-power radio frequency energy.

[0064] The sampling plate 2 is provided on the housing 3 and is provided with a copper screw 4 for connecting the sampling plate 2 with the inner conductor tube 9 and the inner conductor 5 to collect voltage signals;

[0065] The sampling board 2 is also provided with an inductor 10 for coupling the current signal through the inner cavity of the housing 3;

[0066] The coupling plate 8 is arranged on the side of the shell 3 and includes a coupling rod mounting plate 81 connected to the shell 3 and a coupling rod 82 connected to the coupling rod mounting plate 81. It is used to form a coupling structure with the inner conductor 5 to realize the RF coupling sampling function.

[0067] A cover plate 7 is further provided on the outside of the coupling plate 8;

[0068] The housing 3 is further provided with an insulating cover 6 at one end of the inner conductor 5 .

[0069] The sampling board 2 has built-in current sampling circuit and voltage sampling circuit

[0070] The voltage sampling circuit includes high-voltage capacitors C1 and C2 that form a capacitive voltage divider;

[0071] The present invention discloses an output matching detection device and method for a radio frequency amplifier system that is adaptable to complex dynamic impedance. The present invention designs a detection device, as shown in the attached Figure 1 As shown, it can be seen that the output matching detection device is located between the RF amplifier and the load, and the output signal of the output matching detection device is sent to the control system, and the control system completes the load impedance adjustment to match the output impedance of the RF amplifier;

[0072] As attached Figure 2 As shown, a part of the device samples the incident and reflected power through the inductor 10 coupling, and then sends them to the multiplier for self-multiplication and then passes through the conditioning circuit to complete the incident power and reflected power amplitude calibration output, which is convenient for the control system to perform power display linear fitting and subsequent excessive reflection protection processing;

[0073] The other part completes the RF current and RF voltage sampling through inductive coupling and capacitive coupling, and then splits them into two paths after filtering;

[0074] One of the RF current and RF voltage is phase-compared to output the RF current and voltage phase difference for the control system to perform subsequent load impedance adjustment. If the load impedance is purely resistive, the RF voltage and current phase difference is 0. If the load impedance is inductive, the current phase lags the voltage phase. If the load impedance is capacitive, the current phase leads the voltage phase.

[0075] The other RF current and RF voltage are detected by diodes and then added and subtracted respectively, and finally divided to obtain the reflection coefficient.

[0076] The control system can perform standing wave ratio protection and corresponding load adjustment according to the reflection coefficient, perform coarse adjustment of load impedance according to the reflection coefficient, and complete fine adjustment of load impedance according to the phase difference.

[0077] At the same time, all detection circuits are hardware analog circuits, which have the advantages of high sensitivity, fast response speed, and structural integration.

[0078] Compared with traditional directional couplers, it can achieve high-precision isolation between incident and reflected signals that is easier to adjust, thus avoiding the influence of isolation on precise measurement that is inevitable in traditional directional couplers.

[0079] Based on this method, the incident voltage and reflected voltage values can be obtained with higher precision, providing feedback control measurement signals for achieving output matching of the load.

[0080] An output matching detection method for a radio frequency amplifier system adapting to complex dynamic impedances comprises:

[0081] Step 1: Assume the incident voltage is U f , the reflected voltage is U r , the characteristic impedance of the transmission line is Z0, the angular frequency is ω, and the transmission speed of the electromagnetic wave in the inner conductor is V;

[0082] When the length of the feeder from the output of the RF amplifier to the RF current and RF voltage sampling coil is X meters, the voltage U at point X is X , current I X The signals are:

[0083]

[0084] Among them U X is the voltage signal, I X is the current signal;

[0085] Step 2: Assume that the mutual inductance between the inner core of the feed tube and the inductor T is M, and the inductance of the inductor T is L. When there is a high-frequency current I on the inner core of the feed tube X When the current flows through, the induced electromotive force generated on the inductor T is e, which is:

[0086] e=jωMI X =(jωL+jωC / / R)I1

[0087] This electromotive force e forms a high-frequency current I1 in the network composed of L, R and C;

[0088] Step 3. Select jωL+jωC / / R, then:

[0089]

[0090] The voltage signal output by current sampling is:

[0091]

[0092] Step 4: Analyze the voltage U obtained on the high-voltage capacitor C2 c_pickup ;

[0093]

[0094] Since L and high-voltage capacitors C1 and C2 are adjustable design parameters, we can know that:

[0095]

[0096]

[0097] Step 5: Adjust the parameters so that k1=k2, then:

[0098]

[0099] The monitoring mechanism for the incident signal and the reflected signal implemented based on the above method can achieve high-precision isolation of the incident signal and the reflected signal that is easier to adjust than the traditional directional coupler, avoiding the influence of the isolation degree that inevitably exists in the traditional directional coupler on the precise measurement.

[0100] Based on this method, the incident voltage and reflected voltage values can be obtained with higher precision, providing feedback control measurement signals for achieving output matching of the load.

[0101] Based on this type of output matching detection method, it can be used to implement a dynamic load detection mechanism in various industrial scenarios such as solar photovoltaics, semiconductors, and coating.

[0102] This method obtains instantaneous information of voltage and current simultaneously, which can achieve high resolution at the sub-µs time level, and then realize the detection of sparking phenomena, which can be used to determine the mechanism of micro-discharge in plasma applications.

[0103] When the voltage transient value sampled by the device exceeds a preset threshold value (referring to the preset amplitude threshold and time threshold), it indicates that the spark is detected, which can be used to analyze the spark phenomenon and determine the process parameters of the load device at this time.

[0104] For example, typical ignition phenomena in plasma generation include:

[0105] 1. Sudden drop in voltage and current, which may be caused by charge accumulation in the plasma process;

[0106] 2. The voltage and current spikes may be caused by the arc extinction of the plasma.

[0107] The device can detect the spark of the US and is used to determine the type of spark and evaluate the magnitude of the spark.

[0108] At the same time, the information can be used to perform necessary maintenance operations on the reaction chamber and can be used to diagnose the status and working conditions of the reaction chamber.

[0109] This method can be used to establish an early detection mechanism for the reaction chamber, where transient changes such as plasma dynamics may occur. The control system can store the long-term operating parameters and laws of the reaction load changes based on the output parameters detected by this device.

[0110] Working principle description:

[0111] Assume the incident voltage is U f , the reflected voltage is U r, the characteristic impedance of the transmission line is Z0, the angular frequency is ω, and the transmission speed of the electromagnetic wave in the inner conductor is V;

[0112] When the length of the feeder from the output of the RF amplifier to the RF current and RF voltage sampling coil is X meters, the voltage U at point X is X , current I X The signals are:

[0113]

[0114] Among them U X is the voltage signal, I X is the current signal;

[0115] Assuming that the mutual inductance between the inner core of the feed tube and the inductor T is M, and the inductance of the inductor T is L, when there is a high-frequency current I on the inner core of the feed tube X When the current flows through, the induced electromotive force generated on the inductor T is e, which is:

[0116] e=jωMI X =(jωL+jωC / / R)I1

[0117] This electromotive force e forms a high-frequency current I1 in the network composed of L, R and C;

[0118] Select jωL+jωC / / R, then:

[0119]

[0120] The voltage signal output by current sampling is:

[0121]

[0122] Analyze the voltage U obtained on the high-voltage capacitor C2 c_pickup ;

[0123]

[0124] Since L and high-voltage capacitors C1 and C2 are adjustable design parameters, we can know that:

[0125]

[0126] Adjust the parameters so that k1=k2, then:

[0127]

[0128]

[0129] The preferred specific embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above specific embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the scope of protection of the present invention.

Claims

1. A method for detecting output matching of a radio frequency amplifier system adapted to complex dynamic impedance, characterized in that: Based on the following devices: A housing, wherein an inner conductor and a radio frequency connector are provided at both ends of the housing, wherein the inner conductor and the radio frequency connector partially extend into the housing and are interconnected; an inner conductor tube is provided in the housing, wherein the inner conductor and the inner cavity of the housing form a coaxial transmission line for transmitting radio frequency energy; A sampling plate is provided on the housing, and copper screws are provided on the sampling plate for connecting the sampling plate with the inner conductor tube and the inner conductor to collect voltage signals; The sampling board is also provided with an inductor for coupling the current signal through the inner cavity of the shell; A coupling plate is provided on the side of the housing and comprises a coupling rod mounting plate connected to the housing and a coupling rod connected to the coupling rod mounting plate, and is used to form a coupling structure with the inner conductor to realize a radio frequency coupling sampling function; A cover plate is also provided on the outer side of the coupling plate; The housing is further provided with an insulating cover at one end of the inner conductor; The sampling board has built-in current sampling circuit and voltage sampling circuit; The voltage sampling circuit includes high-voltage capacitors C1 and C2 that form a capacitive voltage divider; The following methods are included: Step 1: Assume the incident voltage is U f , the reflected voltage is U r , the characteristic impedance of the transmission line is Z0, the angular frequency is ω, and the transmission speed of the electromagnetic wave in the inner conductor is V; When the length of the feeder from the output of the RF amplifier to the RF current and RF voltage sampling coil is X meters, the voltage U at point X is X , current I X The signals are: Where, j represents the imaginary part; Step 2: Assume that the mutual inductance between the inner core of the feed tube and the inductor T is M, and the inductance of the inductor T is L. When there is a high-frequency current I on the inner core of the feed tube X When the current flows through, the induced electromotive force generated on the inductor T is e, which is: e=jωMI X =(jωL+jωC / / R)I1 This electromotive force e forms a high-frequency current I1 in the network composed of L, R and C; Step 3. Select jωL+jωC / / R, then: The voltage signal output by current sampling is: Step 4: Analyze the voltage U obtained on the high-voltage capacitor C2 c_pickup ; Since L and high-voltage capacitors C1 and C2 are adjustable design parameters, we can know that: Step 5: Adjust the parameters so that k1=k2, then: U f_pickup Represents the forward power sampling, U r_pickup Represents the sampling of reverse power, U c_pickup Indicates the voltage obtained on the high-voltage capacitor C2, U i_pickup Represents the voltage signal output by current sampling.

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