SUMMERY OF THE UTILITY MODEL
In view of the above, there is a need to provide a radio frequency power supply system capable of fast adjustment.
A radio frequency power supply system, the system comprising a radio frequency power supply, an impedance matching network, an impedance adjusting network, and a load impedance, the impedance matching network being electrically connected to the radio frequency power supply, the impedance adjusting network, and the load impedance, respectively, the impedance adjusting network being further electrically connected to the load impedance, wherein:
the impedance adjusting network is used for generating at least one control voltage according to an incident signal and a reflected signal between the impedance matching network and a load impedance, and sending the control voltage to the impedance matching network, wherein the incident signal is a signal transmitted to the load impedance by the impedance matching network, and the reflected signal is a signal returned to the impedance matching network by the load impedance;
the impedance matching network is used for adjusting impedance according to the control voltage to obtain adjusted matching impedance; wherein a sum of the matching impedance and the load impedance is equal to a supply impedance of the radio frequency power supply.
Optionally, the impedance adjusting network includes a directional coupler, an amplitude and phase measuring chip and a control module, the amplitude and phase measuring chip is electrically connected to the directional coupler and the control module, respectively, and the control module is electrically connected to the impedance matching network.
Optionally, the directional coupler is configured to collect an incident signal and a reflected signal between the impedance matching network and a load impedance;
the amplitude and phase measurement chip is used for comparing the incident signal with the reflected signal to obtain a comparison result, and generating a difference voltage according to the incident signal and the reflected signal when the comparison result indicates that a difference exists between the incident signal and the reflected signal, wherein the difference voltage comprises an amplitude difference voltage and a phase angle difference voltage;
the control module is configured to generate at least one control voltage from the magnitude difference voltage and the phase angle difference voltage and transmit the control voltage to the impedance matching network.
Optionally, the impedance adjusting network further includes an attenuation network, and the attenuation network is electrically connected to the amplitude-phase measuring chip and the directional coupler, and is configured to attenuate the incident signal and the reflected signal acquired by the directional coupler to obtain an attenuated incident signal and an attenuated reflected signal, and send the attenuated incident signal and the attenuated reflected signal to the amplitude-phase measuring chip for comparison.
Optionally, the amplitude-phase measurement chip is further configured to stop generating the differential voltage when the comparison result indicates that there is no difference between the incident signal and the reflected signal, and enable the directional coupler to collect the incident signal and the reflected signal between the impedance matching network and the load impedance.
Optionally, the control module includes a control chip and a controlled voltage source, and the control chip is configured to generate at least one control signal according to the amplitude difference voltage and the phase angle difference voltage; the controlled voltage source is used for converting the control signal to generate a corresponding control voltage and transmitting the control voltage to the impedance matching network.
Optionally, the impedance matching network includes a first branch, a second branch, a third branch and a fourth branch, a first end of the first branch and a first end of the fourth branch are electrically connected to a first node, a second end of the first branch and a first end of the second branch are electrically connected to a second node, a second end of the second branch and a first end of the third branch are electrically connected to a third node, a second end of the third branch and a second end of the fourth branch are electrically connected to a fourth node, the first node is electrically connected to the first end of the rf power supply, the second node is electrically connected to the second end of the rf power supply, the third node is electrically connected to the directional coupler, and the fourth node is electrically connected to the load impedance.
Optionally, the first branch and the second branch are inductance branches, and the inductance branches include a first capacitor and a first inductor connected in series.
Optionally, the third branch and the fourth branch are capacitance branches, and the capacitance branches include a second capacitor.
Optionally, the control voltage includes a first voltage and a second voltage, where the first voltage and the second voltage respectively correspond to different control signals, and the controlled voltage source is further configured to transmit the first voltage to an inductance branch in the impedance matching network, so that the impedance matching network adjusts an impedance of the inductance branch according to the first voltage; and transmitting the second voltage to a capacitor branch in the impedance matching network, so that the impedance matching network adjusts the impedance of the capacitor branch according to the second voltage.
One of the above technical solutions has the following advantages and beneficial effects:
the impedance adjusting network determines the loss degree of signal transmission power according to incident signals and reflected signals between the impedance matching network and load impedance, at least one control voltage is generated and sent to the impedance matching network for impedance adjustment, the impedance of the impedance matching network is adjusted through the control voltage, the impedance of the impedance matching network does not need to be changed through a servo stepping motor, the impedance matching process is shortened, and therefore the impedance matching speed is greatly improved.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
As shown in fig. 1, the radio frequency power supply system includes a radio frequency power supply 110, an impedance matching network 120, an impedance adjusting network 130, and a load impedance 140, where the impedance matching network 120 is electrically connected to the radio frequency power supply 110, the impedance adjusting network 130, and the load impedance 140, and the impedance adjusting network 130 is further electrically connected to the load impedance 140.
The impedance adjusting network 130 is configured to generate at least one control voltage according to the incident signal and the reflected signal between the impedance matching network 120 and the load impedance 140, and send the control voltage to the impedance matching network 120.
The incident signal is a signal transmitted by the impedance matching network 120 to the load impedance 140, and the reflected signal is a signal returned by the load impedance 140 to the impedance matching network 120.
Specifically, the loss degree of the signal transmission power between the impedance matching network 120 and the load impedance 140 can be determined according to the incident signal and the reflected signal, that is, whether the power generated by the radio frequency power supply 110 is completely transmitted to the load impedance 140 is determined, and if the incident signal and the reflected signal are the same and have no difference, it indicates that the power generated by the radio frequency power supply 110 is completely transmitted to the load impedance 140; if there is a difference between the incident signal and the reflected signal, it indicates that the power generated by the rf power source 110 is not completely transmitted to the load impedance 140, and therefore the impedance of the impedance matching network 120 needs to be adjusted, and then the incident signal and the reflected signal are used to generate corresponding control voltages, which may be one or more control voltages, and there is a correlation between the control voltages.
The impedance matching network 120 is configured to adjust impedance according to the control voltage to obtain an adjusted matching impedance.
Wherein the sum of the matching impedance and the load impedance 140 is equal to the power supply impedance of the rf power supply 110.
Specifically, the impedance matching network 120 is a network formed by combining a capacitor and an inductor, the control voltage is used for adjusting the capacitance of the capacitor and/or the inductance of the inductor in the impedance matching network 120, a corresponding matching impedance is generated by calculation according to the adjusted capacitance and inductance, the capacitance and inductance in the impedance matching network 120 are directly adjusted by the control voltage, and the impedance of the impedance matching network 120 is not required to be changed by a servo stepper motor, so that the impedance matching process is shortened, the impedance matching speed is increased, the sum of the adjusted matching impedance and the load impedance 140 is equal to the power supply impedance of the radio frequency power supply 110, and the power generated by the radio frequency power supply 110 after the impedance adjustment can be completely transmitted to the load impedance 140, so as to reduce the loss of signal transmission power.
In one embodiment, as shown in fig. 2, the impedance adjusting network 130 includes a directional coupler 131, a magnitude and phase measuring chip 132 and a control module 133, the magnitude and phase measuring chip 132 is electrically connected to the directional coupler 131 and the control module 133, respectively, and the control module 133 is electrically connected to the impedance matching network 120.
Specifically, the directional coupler 131 includes a first coupler and a second coupler, the first coupler is configured to collect an incident signal, the second coupler is configured to collect a reflected signal, the first coupler is electrically connected to the impedance matching network 120 and the load impedance 140, the second coupler is electrically connected to the impedance matching network 120 and the load impedance 140, the amplitude and phase measurement chip 132 may adopt any chip capable of simultaneously measuring an amplitude ratio and a phase difference between two input signals within a specified frequency range, and in this embodiment, a chip with a model number of AD8302 is used as the amplitude and phase measurement chip 132.
In one embodiment, the directional coupler 131 is used to collect incident and reflected signals between the impedance matching network 120 and the load impedance 140; the amplitude and phase measurement chip 132 is configured to compare the incident signal with the reflected signal to obtain a comparison result, and generate a difference voltage according to the incident signal and the reflected signal when the comparison result indicates that a difference exists between the incident signal and the reflected signal, where the difference voltage includes an amplitude difference voltage and a phase angle difference voltage; the control module 133 is configured to generate at least one control voltage according to the magnitude difference voltage and the phase angle difference voltage, and transmit the control voltage to the impedance matching network 120.
Specifically, the directional coupler 131 collects the incident and reflected signals between the impedance matching network 120 and the load impedance 140And sending the incident signal and the reflected signal to the amplitude-phase measurement chip 132 for comparison, wherein the amplitude-phase measurement chip 132 compares the amplitude and the phase between the incident signal and the reflected signal to obtain a comparison result, the comparison result is used for indicating the amplitude difference and the phase difference between the incident signal and the reflected signal, when the comparison result indicates that the amplitude difference and the phase difference exist between the incident signal and the reflected signal, a corresponding amplitude difference voltage and a corresponding phase angle difference voltage are generated according to the incident signal and the reflected signal, and the amplitude difference voltage is marked as VMAGThe phase angle difference voltage is denoted as VPHSThe relationship between the amplitude difference voltage and the phase angle difference voltage and the incident signal and the reflected signal is as follows:
VPHS=VΦ[φ(VINPA)-φ(VINPB)]
wherein, VINPAIs the amplitude of the incident signal, VINPBFor the amplitude of the reflected signal, phi (V)INPA) Is the phase of the incident signal, phi (V)INPB) For reflecting the phase of the signal, VLSPFor indicating the amount of change, V, in the output voltage of the input signal of the amplitude-phase measuring chip 132 when the amplitude ratio thereof changes by 1dBΦFor indicating the amount of change in the output voltage of the amplitude-phase measuring chip 132 when the phase change of the input signal is 1 °.
The amplitude-phase measurement chip 132 sends the amplitude difference voltage and the phase angle difference voltage to the main control module for processing, so as to obtain an incident signal and a reflected signal after attenuation processing, the control module 133 determines the impedance quantity to be adjusted of the impedance matching network 120 according to the amplitude difference voltage and the phase angle difference voltage, and then generates a corresponding control voltage according to the impedance quantity to be adjusted, and the control voltage is recorded as VctrIf a control voltage is generated, the capacitance of all or part of the capacitors in the impedance matching network 120 is controlled according to the control voltage, that is, the capacitance of all or part of the capacitors in the impedance matching network 120 is adjusted by a control voltage, so thatObtaining the matching impedance of the impedance matching network 120 according to the adjusted capacitance, wherein the sum of the matching impedance and the load impedance 140 is equal to the power supply impedance; if two or more control voltages are generated, each control voltage may be used to adjust the capacitance of one or more capacitors in the impedance matching network 120, so as to obtain the matching impedance of the impedance matching network 120 according to the adjusted capacitance, and make the sum of the matching impedance and the load impedance 140 equal to the power supply impedance.
In an embodiment, as shown in fig. 3, the impedance adjusting network further includes an attenuation network, and the attenuation network 134 is electrically connected to the amplitude-phase measuring chip 132 and the directional coupler 131, and is configured to perform attenuation processing on the incident signal and the reflected signal collected by the directional coupler 131 to obtain an attenuated incident signal and an attenuated reflected signal, and send the attenuated incident signal and the attenuated reflected signal to the amplitude-phase measuring chip 132 for comparison processing.
Specifically, before sending the incident signal and the reflected signal to the amplitude-phase measurement chip, the directional coupler also sends the incident signal and the reflected signal to the attenuation network 134 for attenuation processing, adjusts the magnitude of the incident signal and the reflected signal through the attenuation network, so as to obtain the incident signal and the reflected signal after attenuation processing, and sends the incident signal and the reflected signal after attenuation processing to the amplitude-phase measurement chip 132 for comparison processing. The attenuation network can also be used in a comparison method measuring circuit to directly read the attenuation value of the network to be measured and improve the effect of impedance matching.
In one embodiment, the amplitude and phase measuring chip 132 is further configured to stop generating the differential voltage when the comparison result indicates that there is no difference between the incident signal and the reflected signal; and causes the directional coupler 131 to collect the incident and reflected signals between the impedance matching network 120 and the load impedance 140.
Specifically, if the comparison result indicates that there is no amplitude difference or phase difference between the incident signal and the reflected signal, the generation of the corresponding amplitude difference voltage and phase angle difference voltage according to the incident signal and the reflected signal is stopped, and the step of continuously acquiring the incident signal and the reflected signal between the impedance matching network 120 and the load impedance 140 by the directional coupler 131 is returned.
In one embodiment, as shown in fig. 4, the control module 133 includes a main control module 1331 and a controlled voltage source 1332, and the control module 133 generates at least one control voltage according to the amplitude difference voltage and the phase angle difference voltage and transmits the control voltage to the impedance matching network 120, including: the main control module 1331 generates at least one control signal according to the amplitude difference voltage and the phase angle difference voltage; the controlled voltage source 1332 converts the control signal to generate the corresponding control voltage, and transmits the control voltage to the impedance matching network 120.
Specifically, the master control module 1331 may be any chip or device capable of implementing data processing, for example, a single chip microcomputer of model STM32, MSP430, or TMS, the master control module 1331 generates a control signal required for impedance adjustment of the impedance matching network 120 according to the amplitude difference voltage and the phase angle difference voltage, the master control module 1331 sends the control signal to the controlled voltage source 1332, the controlled voltage source 1332 converts the control signal into a corresponding control voltage, and sends the control voltage to one or more capacitors to be adjusted in the impedance matching network 120 to adjust the capacitance of the capacitor.
As shown in fig. 5, the controlled voltage source 1332 includes a first resistor R1, a second resistor R2 and a comparator, so as to form an operational amplifier structure, and the control signal V of the controlled voltage source 1332 is inputtedctrConversion to a control voltage V1Output to the impedance matching network 120.
In one embodiment, as shown in fig. 6, the impedance matching network 120 includes a first branch, a second branch, a third branch and a fourth branch, a first end of the first branch and a first end of the fourth branch are electrically connected to a first node, a second end of the first branch and a first end of the second branch are electrically connected to a second node, a second end of the second branch and a first end of the third branch are electrically connected to a third node, a second end of the third branch and a second end of the fourth branch are electrically connected to a fourth node, the first node is electrically connected to the first end of the rf power source 110, the second node is electrically connected to the second end of the rf power source 110, the third node is electrically connected to the directional coupler 131, and the fourth node is electrically connected to the load impedance 140.
Specifically, in this way, the impedance matching network 120 adopts a symmetric X-type matching network, and compared with the conventional pi-type, L-type and Γ -type networks, the number of variable capacitors and variable inductors in the symmetric X-type matching network is increased, and the adjustment range of the impedance is expanded under the condition that the control signal is not changed.
In one embodiment, the first branch and the third branch are inductive branches, and the inductive branches include a first capacitor and a first inductor connected in series.
Specifically, as shown in fig. 6, the first capacitance in the first branch is C1The first inductance in the first branch is L1First capacitor C in the first branch1As a first end of a first branch, in which a first capacitor C is present1Second terminal and first inductor L1The first end of the first branch circuit is electrically connected with a first inductor L in the first branch circuit1As the second end of the first branch. The first capacitor in the third branch is C2The first inductance in the third branch is L2A first capacitor C in the third branch2As the first end of the third branch, a first capacitor C in the third branch2Second terminal and first inductor L2The first end of the third branch is electrically connected with the first inductor L in the third branch2As the second end of the third branch.
In one embodiment, the second branch and the fourth branch are capacitive branches, and the capacitive branches include a second capacitor and a third capacitor connected in series.
Specifically, as shown in fig. 6, the second capacitance in the second branch is CAThe third capacitance in the second branch is C5A second capacitor C in the second branch4First end ofA first end of the second branch, a second capacitor C in the second branch4Second terminal and third capacitor C5The first end of the second branch is electrically connected with the third capacitor C5As the second end of the second branch. The second capacitance in the fourth branch is C3The third capacitance in the fourth branch is C6A second capacitor C in the fourth branch3As the first end of the fourth branch, a second capacitor C in the fourth branch3Second terminal of and third capacitor C6The first end of the fourth branch is electrically connected with the third capacitor C6As the second end of the fourth branch.
In one embodiment, the control voltage includes a first voltage and a second voltage, where the first voltage and the second voltage respectively correspond to different control signals, and the controlled voltage source 1332 transmits the first voltage to an inductive branch in the impedance matching network 120, so that the impedance matching network 120 adjusts the impedance of the inductive branch according to the first voltage; the controlled voltage source 1332 transmits the second voltage to a capacitive branch in the impedance matching network 120, so that the impedance matching network 120 adjusts the impedance of the capacitive branch according to the second voltage.
Specifically, the control voltage includes a first voltage Vctr1And a second voltage Vctr2As shown in fig. 6, the first voltage is used to adjust the impedances of the first branch and the third branch to realize the inductance adjustment of the variable inductor, and the second voltage is used to adjust the impedances of the second branch and the fourth branch to realize the capacitance adjustment of the variable capacitor, so as to obtain the adjusted matching impedance to realize the optimal impedance matching relationship, which is as follows:
Zin=Zs
the input impedance expression considering the load impedance 140 and the impedance matching network 120 is as follows:
wherein Z is
sFor indicating the
load impedance 140 to be applied,
thereby achieving an optimal impedance matching relationship by adjusting the capacitance and inductance in the impedance matching network 120.
The capacitors in the impedance matching network 120 are all voltage-controlled capacitors, as shown in fig. 7, the voltage-controlled capacitor is formed by connecting AB and BC in parallel, and the capacitance C is a capacitance at both AC ends, which is equivalent to the capacitance C of ABABAnd a capacitance value C of BCBCIn parallel, by changing UABAnd/or UBCThe capacitance value C is determined by the part with smaller capacitance, if C is equal to C, because AB and BC are made of dielectrics with different dielectric constants and are connected in parallel with each otherAB>CBCThen by changing UBCTo change the capacitance value C; if CBC>CABThen by changing UABTo change the capacitance value C.
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several implementation modes of the present application, and the description thereof is specific and detailed, but not construed as limiting the scope of the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent application shall be subject to the appended claims.