Load impedance acquisition device and radio frequency power supply system

Abstract

The invention provides a load impedance acquisition device and a radio frequency power supply system. The load impedance acquisition device comprises a sampling unit, a first arithmetic unit and a second arithmetic unit. The sampling unit is used for acquiring a voltage waveform signal and a current waveform signal of a radio-frequency signal output to a load by a radio-frequency power supply, and sampling the voltage waveform signal and the current waveform signal respectively by taking 1 / 4 of the cycle time of the radio-frequency signal as a time interval, so as to correspondingly obtain four sampling voltage values and four sampling current values; the first operation unit is used for operating the four sampling voltage values to obtain a first operation voltage value and a second operation voltage value, and operating the four sampling current values to obtain a first operation current value and a second operation current value; the second operation unit is used for obtaining an impedance module value of the load according to the first operation voltage value, the second operation voltage value, the first operation current value and the second operation current value. The impedance condition of the load can be quickly determined.

Description

Technical Field

[0001] The present application relates to the field of radio frequency technology, and in particular to a load impedance acquisition device and a radio frequency power supply system having the load impedance acquisition device. Background Art

[0002] At present, with the development of RF power technology, the application of RF power is becoming more and more extensive. When the RF power is output to the load, the RF power and the load need to be impedance matched. Among them, determining the impedance of the load is of great significance for the impedance matching between the RF power and the load. Therefore, when the RF power outputs RF signals, how to quickly determine the impedance of the load in order to quickly complete impedance matching and achieve the best output effect has become a problem that needs to be considered. Summary of the invention

[0003] The present application provides a load impedance acquisition device and a radio frequency power supply system, which can quickly determine the impedance of the load.

[0004] In a first aspect, a load impedance acquisition device is provided, the load impedance acquisition device comprising a sampling unit, a first operation unit and a second operation unit. The sampling unit is used to connect with the output path of the radio frequency power supply to obtain the voltage waveform signal and the current waveform signal of the radio frequency signal output by the radio frequency power supply to the load, and sample the voltage waveform signal and the current waveform signal respectively at a time interval of 1 / 4 of the cycle time of the radio frequency signal within a preset time length, so as to obtain four sampled voltage values ​​and four sampled current values, wherein the preset time length is equal to one cycle time of the radio frequency signal. The first operation unit is connected to the sampling unit, and the first operation unit is used to perform two-by-two operations on the four sampled voltage values ​​to obtain a first operation voltage value and a second operation voltage value, and to perform two-by-two operations on the four sampled current values ​​to obtain a first operation current value and a second operation current value. The second operation unit is connected to the first operation unit, and the second operation unit is used to perform operations according to the first operation voltage value, the second operation voltage value, the first operation current value and the second operation current value to obtain the impedance modulus value of the load. Wherein, the waveform of the voltage waveform signal and the waveform of the current waveform signal are both sine waves.

[0005] In a possible implementation, the four sampled voltage values ​​include a first sampled voltage value, a second sampled voltage value, a third sampled voltage value, and a fourth sampled voltage value obtained by sequentially sampling the voltage waveform signal at a time interval of 1 / 4 of the cycle time of the RF signal; the first operation unit is used to perform a subtraction operation on the first sampled voltage value and the third sampled voltage value to obtain a first operation voltage value, and to perform a subtraction operation on the second sampled voltage value and the fourth sampled voltage value to obtain a second operation voltage value. The four sampled current values ​​include a first sampled current value, a second sampled current value, a third sampled current value, and a fourth sampled current value obtained by sequentially sampling the current waveform signal at a time interval of 1 / 4 of the cycle time of the RF signal; the first operation unit is used to perform a subtraction operation on the first sampled current value and the third sampled current value to obtain a first operation current value, and to perform a subtraction operation on the second sampled current value and the fourth sampled current value to obtain a second operation current value.

[0006] In one possible implementation, the second operation unit is used to perform operations based on the first operation voltage value and the second operation voltage value to obtain a voltage modulus, and to perform operations based on the first operation current value and the second operation current value to obtain a current modulus, and to perform operations based on the voltage modulus and the current modulus to obtain an impedance modulus of the load.

[0007] In a possible implementation manner, the voltage modulus is a ratio of the square root of the sum of the square of the first operating voltage value and the square of the second operating voltage value to a constant 2. The current modulus is a ratio of the square root of the sum of the square of the first operating current value and the square of the second operating current value to a constant 2. The impedance modulus of the load is a ratio of the voltage modulus to the current modulus.

[0008] In a possible implementation, the load impedance acquisition device further includes an angle acquisition unit and a third operation unit. The angle acquisition unit is connected between the sampling unit and the third operation unit, and the angle acquisition unit is used to acquire the waveform phase angle between the voltage waveform signal and the current waveform signal. The third operation unit is also connected to the second operation unit, and the third operation unit is used to perform operation according to the impedance modulus value of the load and the waveform phase angle to obtain the impedance value of the load.

[0009] In a possible implementation, the impedance value of the load includes a real part and an imaginary part, and the impedance value of the load is the sum of the real part of the impedance value of the load and the imaginary part of the impedance value of the load. The real part of the impedance value of the load is the product of the impedance modulus of the load and the cosine value of the waveform phase angle, and the imaginary part of the impedance value of the load is the product of the impedance modulus of the load, the sine value of the waveform phase angle, and the imaginary unit.

[0010] In a possible implementation, the angle acquisition unit includes a phase detector and a table lookup device, and the phase detector and the table lookup device are sequentially connected between the sampling unit and the third operation unit. The phase detector is used to obtain a phase voltage value according to the voltage waveform signal and the current waveform signal. The table lookup device is used to determine the waveform phase angle corresponding to the phase voltage value according to the correspondence between multiple preset waveform phase angles and multiple phase voltage values.

[0011] In a possible implementation, the sampling unit includes a first signal acquisition circuit, a second signal acquisition circuit, a first sampler, and a second sampler, wherein the first signal acquisition circuit and the second signal acquisition circuit are both used to connect to the output path of the RF power supply, the first sampler is connected between the first signal acquisition circuit and the first operation unit, and the second sampler is connected between the second signal acquisition circuit and the first operation unit. The first signal acquisition circuit is used to acquire the voltage waveform signal, and the first sampler is used to sample the voltage waveform signal at a time interval of 1 / 4 of the cycle time of the RF signal to obtain the four sampled voltage values. The second signal acquisition circuit is used to acquire the current waveform signal, and the second sampler is used to sample the current waveform signal at a time interval of 1 / 4 of the cycle time of the RF signal to obtain the four sampled current values.

[0012] In a possible implementation manner, the first operation unit is further configured to reduce the four sampled voltage values ​​and then perform pairwise operations on the four reduced sampled voltage values, and to reduce the four sampled current values ​​and then perform pairwise operations on the four reduced sampled current values.

[0013] In a second aspect, a radio frequency power supply system is also provided, the radio frequency power supply system includes a radio frequency power supply and a load impedance acquisition device. The load impedance acquisition device includes a sampling unit, a first operation unit and a second operation unit. The sampling unit is used to connect to the output path of the radio frequency power supply to obtain the voltage waveform signal and the current waveform signal of the radio frequency signal output by the radio frequency power supply to the load, and sample the voltage waveform signal and the current waveform signal respectively at a time interval of 1 / 4 of the cycle time of the radio frequency signal within a preset time length, so as to obtain four sampled voltage values ​​and four sampled current values, wherein the preset time length is equal to one cycle time of the radio frequency signal. The first operation unit is connected to the sampling unit, and the first operation unit is used to perform two-by-two operations on the four sampled voltage values ​​to obtain a first operation voltage value and a second operation voltage value, and to perform two-by-two operations on the four sampled current values ​​to obtain a first operation current value and a second operation current value. The second operation unit is connected to the first operation unit, and the second operation unit is used to perform operations according to the first operation voltage value, the second operation voltage value, the first operation current value and the second operation current value to obtain the impedance modulus value of the load. Wherein, the waveform of the voltage waveform signal and the waveform of the current waveform signal are both sine waves.

[0014] The load impedance acquisition device and the radio frequency power supply system of the present application are configured to sample the voltage waveform signal and the current waveform signal respectively at a time interval of 1 / 4 of the cycle time of the radio frequency signal in one cycle time of the radio frequency signal, so as to obtain four sampled voltage values ​​and four sampled current values ​​accordingly, and to perform pairwise operations on the four sampled voltage values ​​and pairwise operations on the four sampled current values ​​by configuring a first operation unit, so that the impedance modulus of the load can be quickly calculated and obtained by configuring a second operation unit according to the first operation voltage value, the second operation voltage value, the first operation current value and the second operation current value obtained by the first operation unit, so as to quickly determine the impedance condition of the load, facilitate rapid completion of impedance matching and achieve the best output effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0016] Figure 1 Schematic diagram of a load impedance acquisition device in an embodiment of the present application.

[0017] Figure 2 It is a schematic diagram of the load impedance acquisition device in another embodiment of the present application.

[0018] Figure 3Schematic diagram of an angle acquisition unit in an embodiment of the present application.

[0019] Figure 4 is a schematic diagram of a sampling unit in an embodiment of the present application.

[0020] Figure 5 FIG. 4 is a schematic diagram of a first computing unit in an embodiment of the present application.

[0021] Figure 6 is a schematic diagram of a radio frequency power supply system in an embodiment of the present application.

[0022] Description of the accompanying drawings: 1000, RF power supply system, RF, RF power supply, RFS, RF signal, 10, load impedance acquisition device, 100, sampling unit, Vs, voltage waveform signal, 110, first signal acquisition circuit, 130, first sampler, Vf, four sampled voltage values, Vs1, first sampled voltage value, Vs2, second sampled voltage value, Vs3, third sampled voltage value, Vs4, fourth sampled voltage value, Is, current waveform signal, 120, second signal acquisition circuit, 140, second sampler, If, four sampled current values, Is1, first sampled current value, Is2, second sampled current value, Is3, third sampled current value, I s4, fourth sampling current value, 200, first operation unit, 210, first subtractor, Vo1, first operation voltage value, 220, second subtractor, Vo2, second operation voltage value, 230, third subtractor, Io1, first operation current value, 240, fourth subtractor, Io2, second operation current value, 250, second converter, 260, reduction module, 300, second operation unit, |Z|, impedance module value, 400, angle acquisition unit, 410, phase detector, Vps, phase voltage signal, 420, first converter, Vp, phase voltage value, 430, lookup table, θ, waveform phase angle, 500, third operation unit, RL, load. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0024] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0025] In the following, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third", and "fourth" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more.

[0026] In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0027] See also Figure 1 , Figure 1 FIG. 1 is a schematic diagram of a load impedance acquisition device in an embodiment of the present application. Figure 1As shown, the present application provides a load impedance acquisition device 10, which includes a sampling unit 100, a first operation unit 200 and a second operation unit 300. The sampling unit 100 is used to connect with the output path of the radio frequency power supply RF to obtain the voltage waveform signal Vs and the current waveform signal Is of the radio frequency signal RFS output by the radio frequency power supply RF to the load RL, and to sample the voltage waveform signal Vs and the current waveform signal Is at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS within a preset time length, so as to obtain four sampled voltage values ​​Vf and four sampled current values ​​If, wherein the preset time length is equal to one cycle time of the radio frequency signal RFS. The first operation unit 200 is connected to the sampling unit 100, and the first operation unit 200 is used to perform two-by-two operations on the four sampled voltage values ​​Vf to obtain a first operation voltage value Vo1 and a second operation voltage value Vo2, and to perform two-by-two operations on the four sampled current values ​​If to obtain a first operation current value Io1 and a second operation current value Io2. The second operation unit 300 is connected to the first operation unit 200, and is used to perform operation according to the first operation voltage value Vo1, the second operation voltage value Vo2, the first operation current value Io1 and the second operation current value Io2 to obtain the impedance modulus value |Z| of the load RL. The waveform of the voltage waveform signal Vs and the waveform of the current waveform signal Is are both sine waves.

[0028] Therefore, the load impedance acquisition device 10 in the present application is configured to sample the voltage waveform signal Vs and the current waveform signal Is at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS during one cycle time of the radio frequency signal RFS, so as to obtain four sampled voltage values ​​Vf and four sampled current values ​​If respectively, and to perform pairwise operations on the four sampled voltage values ​​Vf and pairwise operations on the four sampled current values ​​If by configuring the first operation unit 200, so as to quickly obtain the impedance modulus value |Z| of the load RL by configuring the second operation unit 300 according to the first operation voltage value Vo1, the second operation voltage value Vo2, the first operation current value Io1 and the second operation current value Io2 obtained by the first operation unit 200, and quickly determine the impedance condition of the load RL, so as to quickly complete impedance matching and achieve the best output effect.

[0029] The current waveform signal Is reflects the current component of the radio frequency signal RFS, and the voltage waveform signal Vs reflects the voltage component of the radio frequency signal RFS.

[0030] The waveform of the voltage waveform signal Vs and the waveform of the current waveform signal Is may both be sine waves or cosine waves.

[0031] Among them, the preset duration is equal to one cycle time of the radio frequency signal RFS, which means that the preset duration is equal to one cycle time, and the start time and end time of the preset duration can be any time, as long as the difference between the end time and the start time is one cycle time.

[0032] like Figure 1 As shown, the four sampled voltage values ​​Vf include a first sampled voltage value Vs1, a second sampled voltage value Vs2, a third sampled voltage value Vs3 and a fourth sampled voltage value Vs4 obtained by sampling the voltage waveform signal Vs in sequence at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS; the first operation unit 200 is used to subtract the first sampled voltage value Vs1 from the third sampled voltage value Vs3 to obtain a first operation voltage value Vo1, and to subtract the second sampled voltage value Vs2 from the fourth sampled voltage value Vs4 to obtain a second operation voltage value Vo2. The four sampling current values ​​If include a first sampling current value Is1, a second sampling current value Is2, a third sampling current value Is3 and a fourth sampling current value Is4 obtained by sampling the current waveform signal Is in sequence at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS; the first operation unit 200 is used to perform a subtraction operation on the first sampling current value Is1 and the third sampling current value Is3 to obtain a first operation current value Io1, and to perform a subtraction operation on the second sampling current value Is2 and the fourth sampling current value Is4 to obtain a second operation current value Io2.

[0033] Thus, in the above-mentioned load impedance acquisition device 10 in the present application, the first operating voltage value Vo1 is the difference between the first sampling voltage value Vs1 and the third sampling voltage value Vs3, the second operating voltage value Vo2 is the difference between the second sampling voltage value Vs2 and the fourth sampling voltage value Vs4, the first operating current value Io1 is the difference between the first sampling current value Is1 and the third sampling current value Is3, and the second operating current value Io2 is the difference between the second sampling current value Is2 and the fourth sampling current value Is4. The obtained first operating voltage value Vo1, second operating voltage value Vo2, first operating current value Io1 and second operating current value Io2 can quickly determine the impedance of the load RL.

[0034] Specifically, taking the waveform of the voltage waveform signal Vs and the waveform of the current waveform signal Is as cosine waves as an example, the first sampling voltage value Vs1, the second sampling voltage value Vs2, the third sampling voltage value Vs3 and the fourth sampling voltage value Vs4 can be |V|×cos(ωt+φ), |V|×cos(ωt+φ+π / 2), |V|×cos(ωt+φ+π) and |V|×cos(ωt+φ+3π / 2), respectively. The current value Is1, the second sampling current value Is2, the third sampling current value Is3 and the fourth sampling current value Is4 can be |I|×cos(ωt+α), |I|×cos(ωt+α+π / 2), |I|×cos(ωt+α+π) and |I|×cos(ωt+α+3π / 2), respectively, wherein |V| is the voltage modulus, |I| is the current modulus, φ is the initial phase angle of the voltage waveform signal Vs, and α is the initial phase angle of the current waveform signal Is. Then the first operating voltage value Vo1, the second operating voltage value Vo2, the first operating current value Io1 and the second operating current value Io2 are respectively |V|×cos(ωt+φ)-|V|×cos(ωt+φ+π), |V|×cos(ωt+φ+π / 2)-|V|×cos(ωt+φ+3π / 2), |I|×cos(ωt+α)-|I|×cos(ωt+α+π) and |I|×cos(ωt+α+π)-|I|×cos(ωt+α+3π / 2).

[0035] like Figure 1 As shown, the second operation unit 300 is used to perform operations according to the first operation voltage value Vo1 and the second operation voltage value Vo2 to obtain a voltage modulus, and to perform operations according to the first operation current value Io1 and the second operation current value Io2 to obtain a current modulus, and to perform operations according to the voltage modulus and the current modulus to obtain an impedance modulus |Z| of the load RL.

[0036] Therefore, the load impedance acquisition device 10 in the present application can calculate the voltage modulus according to the first calculated voltage value Vo1 and the second calculated voltage value Vo2, and can calculate the current modulus according to the first calculated current value Io1 and the second calculated current value Io2, and then obtain the voltage modulus and the current modulus, and also obtain the impedance modulus |Z| of the load RL.

[0037] In one or more embodiments, the voltage modulus is the ratio of the square root of the sum of the squares of the first operational voltage value Vo1 and the second operational voltage value Vo2 to a constant 2. The current modulus is the ratio of the square root of the sum of the squares of the first operational current value Io1 and the second operational current value Io2 to a constant 2. The impedance modulus |Z| of the load RL is the ratio of the voltage modulus to the current modulus.

[0038] Therefore, the load impedance acquisition device 10 in the present application can obtain the voltage modulus by performing the above operation on the first operation voltage value Vo1 and the second operation voltage value Vo2 according to the conversion formula related to the trigonometric function, and can obtain the current modulus by performing the above operation on the first operation current value Io1 and the second operation current value Io2, and then can quickly determine the impedance modulus |Z| of the load RL according to the voltage modulus and the current modulus.

[0039] Specifically, the voltage modulus is the ratio of the square root of the sum of the squares of the first operation voltage value Vo1 and the second operation voltage value Vo2 to the constant 2, that is, |V|=[√(Vo1 2 +Vo2 2 )] / 2. The current modulus is the ratio of the square root of the sum of the squares of the first operating current value Io1 and the second operating current value Io2 to the constant 2, that is, |I|=[√(Io1 2 +Io2 2 )] / 2. The impedance modulus |Z| of the load RL is the ratio of the voltage modulus to the current modulus, that is, |Z|=|V| / |I|.

[0040] See also Figure 2 , Figure 2 FIG. 1 is a schematic diagram of a load impedance acquisition device in another embodiment of the present application. Figure 2 As shown, the load impedance acquisition device 10 further includes an angle acquisition unit 400 and a third operation unit 500. The angle acquisition unit 400 is connected between the sampling unit 100 and the third operation unit 500, and the angle acquisition unit 400 is used to acquire the waveform phase angle θ between the voltage waveform signal Vs and the current waveform signal Is. The third operation unit 500 is also connected to the second operation unit 300, and the third operation unit 500 is used to perform operations according to the impedance modulus value |Z| of the load RL and the waveform phase angle θ to obtain the impedance value of the load RL.

[0041] Therefore, the load impedance acquisition device 10 in the present application acquires the waveform phase angle θ between the voltage waveform signal Vs and the current waveform signal Is by setting the angle acquisition unit 400, and then can quickly obtain the impedance value of the load RL according to the impedance modulus |Z| and the waveform phase angle θ of the load RL, further determine the impedance condition of the load RL, and more conveniently complete impedance matching to achieve the best output effect.

[0042] Specifically, the waveform phase angle θ is the difference between the initial phase angle of the voltage waveform signal Vs and the initial phase angle of the current waveform signal Is, that is, the waveform phase angle θ=φ-α.

[0043] In one or more embodiments, the impedance value of the load RL includes a real part and an imaginary part, and the impedance value of the load RL is the sum of the real part of the impedance value of the load RL and the imaginary part of the impedance value of the load RL. The real part of the impedance value of the load RL is the product of the impedance modulus value |Z| of the load RL and the cosine value of the waveform phase angle θ, and the imaginary part of the impedance value of the load RL is the product of the impedance modulus value |Z| of the load RL, the sine value of the waveform phase angle θ, and the imaginary unit.

[0044] Therefore, the load impedance acquisition device 10 in the present application can obtain the real part and the imaginary part of the impedance value of the load RL respectively according to the impedance modulus |Z|, the waveform phase angle θ and the imaginary unit of the load RL, and further determine the impedance value of the load RL.

[0045] Specifically, the impedance value Z=R+X×j of the load RL is taken as an example for explanation, wherein R is the real part of the impedance value of the load RL, X is the imaginary part of the impedance value of the load RL, and j is an imaginary unit, then R=|Z|×cosθ, X=|Z|×sinθ.

[0046] Please also read Figure 3 , Figure 3 FIG. 1 is a schematic diagram of an angle acquisition unit in an embodiment of the present application. Figure 2 , Figure 3 As shown, the angle acquisition unit 400 includes a phase detector 410 and a table lookup 430, which are sequentially connected between the sampling unit 100 and the third operation unit 500. The phase detector 410 is used to obtain the phase voltage value Vp according to the voltage waveform signal Vs and the current waveform signal Is. The table lookup 430 is used to determine the waveform phase angle θ corresponding to the phase voltage value Vp according to the corresponding relationship between the preset multiple waveform phase angles θ and the multiple phase voltage values ​​Vp.

[0047] Therefore, the load impedance acquisition device 10 in the present application can quickly determine the waveform phase angle θ by providing the phase detector 410 and the table lookup device 430 .

[0048] like Figure 3 As shown, when the phase detector 410 can only be used to obtain the phase voltage signal Vps according to the voltage waveform signal Vs and the current waveform signal Is, the angle acquisition unit 400 can also include a first converter 420 connected between the phase detector 410 and the look-up table 430, and the first converter 420 is used to convert the phase voltage signal Vps into a corresponding phase voltage value Vp.

[0049] Please also read Figure 4 , Figure 4 FIG. 1 is a schematic diagram of a sampling unit in an embodiment of the present application. Figure 1 , Figure 4As shown, the sampling unit 100 includes a first signal acquisition circuit 110, a second signal acquisition circuit 120, a first sampler 130 and a second sampler 140. The first signal acquisition circuit 110 and the second signal acquisition circuit 120 are both used to connect to the output path of the radio frequency power supply RF. The first sampler 130 is connected between the first signal acquisition circuit 110 and the first operation unit 200, and the second sampler 140 is connected between the second signal acquisition circuit 120 and the first operation unit 200. The first signal acquisition circuit 110 is used to acquire the voltage waveform signal Vs, and the first sampler 130 is used to sample the voltage waveform signal Vs at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS to obtain four sampled voltage values ​​Vf. The second signal acquisition circuit 120 is used to acquire the current waveform signal Is, and the second sampler 140 is used to sample the current waveform signal Is at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS to obtain four sampled current values ​​If.

[0050] Therefore, the load impedance acquisition device 10 in the present application can obtain four sampled voltage values ​​Vf and four sampled current values ​​If correspondingly by setting the first sampler 130 and the second sampler 140 to sample the voltage waveform signal Vs and the current waveform signal Is at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS.

[0051] The sampling frequency of the first sampler 130 and the sampling frequency of the second sampler 140 are both 1 / 4 of the frequency of the radio frequency signal RFS.

[0052] In one or more embodiments, the first signal acquisition circuit 110 may include a resistor voltage-dividing acquisition circuit connected between the output path of the radio frequency power source RF and the ground, the resistor voltage-dividing acquisition circuit includes two resistors connected in series, and the connection point between the two resistors is used to output the voltage waveform signal Vs. The first signal acquisition circuit 110 may also include a capacitor voltage-dividing acquisition circuit connected between the output path of the radio frequency power source RF and the ground, the capacitor voltage-dividing acquisition circuit includes two capacitors connected in series, and the connection point between the two capacitors is used to output the voltage waveform signal Vs. The first signal acquisition circuit 110 may also include a voltage sensor or other devices that can be used to acquire the voltage waveform signal Vs.

[0053] In one or more embodiments, the second signal acquisition circuit 120 may include a current transformer connected in the output path of the RF power source RF, that is, a current transformer connected between the RF power source RF and the load RL. The second signal acquisition circuit 120 may also include a current sensor or other devices that can be used to obtain the current waveform signal Is.

[0054] See also Figure 5 , Figure 5FIG. 1 is a schematic diagram of a first computing unit in an embodiment of the present application. Figure 5 As shown, the first operation unit 200 is further used to reduce four sampled voltage values ​​Vf and then perform two-by-two operations on the reduced four sampled voltage values ​​Vf, and to reduce four sampled current values ​​If and then perform two-by-two operations on the reduced four sampled current values ​​If.

[0055] Therefore, the load impedance acquisition device 10 in the present application, since the power of the RF signal RFS output by the RF power supply RF is very large, by reducing the four sampling voltage values ​​Vf and the four sampling current values ​​If, the first operation unit 200 can perform normal operations on the four sampling voltage values ​​Vf and the four sampling current values ​​If, and the second operation unit 300 can also perform normal operations.

[0056] Please also read Figure 1 .like Figure 1 , Figure 5 As shown, the first operation unit 200 may include a first subtractor 210, a second subtractor 220, a third subtractor 230, a fourth subtractor 240 and a reduction module 260. The input ends of the first subtractor 210, the second subtractor 220, the third subtractor 230 and the fourth subtractor 240 are all connected to the sampling unit 100 through the reduction module 260, and the output ends of the first subtractor 210, the second subtractor 220, the third subtractor 230 and the fourth subtractor 240 are all connected to the second operation unit 300. Among them, the first subtractor 210 is used to perform a subtraction operation on the first sampled voltage value Vs1 and the third sampled voltage value Vs3 to obtain a first operation voltage value Vo1; the second subtractor 220 is used to perform a subtraction operation on the second sampled voltage value Vs2 and the fourth sampled voltage value Vs4 to obtain a second operation voltage value Vo2; the third subtractor 230 is used to perform a subtraction operation on the first sampled current value Is1 and the third sampled current value Is3 to obtain a first operation current value Io1; the fourth subtractor 240 is used to perform a subtraction operation on the second sampled current value Is2 and the fourth sampled current value Is4 to obtain a second operation current value Io2; the reduction module 260 is used to reduce the four sampled voltage values ​​Vf, and then perform a pairwise operation on the four reduced sampled voltage values ​​Vf, and reduce the four sampled current values ​​If, and then perform a pairwise operation on the four reduced sampled current values ​​If.

[0057] In one or more embodiments, the decomposition module 260 may include four capacitors, one end of the four capacitors is connected to the connection points between the sampling unit 100 and the input ends of the first subtractor 210, the second subtractor 220, the third subtractor 230, and the fourth subtractor 240, respectively, and the other ends of the four capacitors are grounded.

[0058] like Figure 1 , Figure 5 As shown, the first operation unit 200 may further include a second converter 250, the input end of the second converter 250 is connected to the output ends of the first subtractor 210, the second subtractor 220, the third subtractor 230, and the fourth subtractor 240, and the output end of the second converter 250 is connected to the second operation unit 300. The second converter 250 is used to convert the operation results of the first subtractor 210, the second subtractor 220, the third subtractor 230, and the fourth subtractor 240 into the corresponding first operation voltage value Vo1, the second operation voltage value Vo2, the first operation current value Io1, and the second operation current value Io2.

[0059] In some embodiments, one or more of the first operation unit 200, the second operation unit 300 and the third operation unit 500 can be an integrated operator, or an operation circuit composed of electronic devices such as operational amplifiers, diodes, capacitors, resistors, etc., or a central processing unit (CPU), a microcontrol unit (MCU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate logic devices, transistor logic devices and other logic control devices. The present application is not limited to this, as long as the corresponding operation can be completed.

[0060] The load impedance acquisition device 10 of the present application, through the above structure, can quickly calculate the impedance modulus |Z| of the load RL, and then can quickly calculate the impedance value of the load RL, so as to quickly determine the impedance condition of the load RL, facilitate rapid completion of impedance matching, and achieve the best output effect.

[0061] See also Figure 6 , Figure 6 FIG. 1 is a schematic diagram of a radio frequency power supply system in an embodiment of the present application. Figure 6 As shown, the present application further provides a radio frequency power supply system 1000, which includes a radio frequency power supply RF and a load impedance acquisition device 10 in any of the aforementioned embodiments.

[0062] Please refer again Figure 1 .like Figure 1As shown, the load impedance acquisition device 10 includes a sampling unit 100, a first operation unit 200 and a second operation unit 300. The sampling unit 100 is used to connect with the output path of the radio frequency power supply RF to obtain the voltage waveform signal Vs and the current waveform signal Is of the radio frequency signal RFS output by the radio frequency power supply RF to the load RL, and to sample the voltage waveform signal Vs and the current waveform signal Is respectively at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS within a preset time length, so as to obtain four sampled voltage values ​​Vf and four sampled current values ​​If, wherein the preset time length is equal to one cycle time of the radio frequency signal RFS. The first operation unit 200 is connected to the sampling unit 100, and the first operation unit 200 is used to perform two-by-two operations on the four sampled voltage values ​​Vf to obtain a first operation voltage value Vo1 and a second operation voltage value Vo2, and to perform two-by-two operations on the four sampled current values ​​If to obtain a first operation current value Io1 and a second operation current value Io2. The second operation unit 300 is connected to the first operation unit 200, and is used to perform operation according to the first operation voltage value Vo1, the second operation voltage value Vo2, the first operation current value Io1 and the second operation current value Io2 to obtain the impedance modulus value |Z| of the load RL. The waveform of the voltage waveform signal Vs and the waveform of the current waveform signal Is are both sine waves.

[0063] The more specific structure of the load impedance acquisition device 10 can refer to the relevant content of the load impedance acquisition device 10 in any of the aforementioned embodiments, which will not be repeated here.

[0064] like Figure 1 , Figure 6 As shown, the radio frequency power supply RF can be used to output a radio frequency signal RFS to the load RL to provide electrical energy to the load RL.

[0065] The load impedance acquisition device 10 and the RF power supply system 1000 of the present application, through the above structure, can quickly calculate the impedance modulus |Z| of the load RL, and then can quickly calculate the impedance value of the load RL, so as to quickly determine the impedance condition of the load RL, facilitate rapid completion of impedance matching, and achieve the best output effect.

[0066] The above description is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application; in the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A load impedance acquisition device, characterized in that: include: A sampling unit, used to be connected to the output path of the RF power supply to obtain a voltage waveform signal and a current waveform signal of the RF signal output by the RF power supply to the load, and to sample the voltage waveform signal and the current waveform signal at a time interval of 1 / 4 of the cycle time of the RF signal within a preset time length, so as to obtain four sampled voltage values ​​and four sampled current values, wherein the preset time length is equal to one cycle time of the RF signal; a first operation unit connected to the sampling unit, the first operation unit being used to perform two-by-two operations on the four sampled voltage values ​​to obtain a first operation voltage value and a second operation voltage value, and to perform two-by-two operations on the four sampled current values ​​to obtain a first operation current value and a second operation current value; a second operation unit connected to the first operation unit, and configured to perform operation according to the first operation voltage value, the second operation voltage value, the first operation current value, and the second operation current value to obtain an impedance modulus value of the load; Wherein, the waveform of the voltage waveform signal and the waveform of the current waveform signal are both sine waves.

2. The load impedance acquisition device according to claim 1, characterized in that: The four sampled voltage values ​​include a first sampled voltage value, a second sampled voltage value, a third sampled voltage value and a fourth sampled voltage value obtained by sequentially sampling the voltage waveform signal at a time interval of 1 / 4 of the cycle time of the radio frequency signal; The first operation unit is used for performing a subtraction operation on the first sampled voltage value and the third sampled voltage value to obtain a first operation voltage value, and performing a subtraction operation on the second sampled voltage value and the fourth sampled voltage value to obtain a second operation voltage value; The four sampled current values ​​include a first sampled current value, a second sampled current value, a third sampled current value, and a fourth sampled current value obtained by sampling the current waveform signal in sequence at a time interval of 1 / 4 of the cycle time of the RF signal; the first operation unit is used to subtract the first sampled current value from the third sampled current value to obtain a first operation current value, and to subtract the second sampled current value from the fourth sampled current value to obtain a second operation current value.

3. The load impedance acquisition device according to claim 1, characterized in that: The second operation unit is used to perform operations based on the first operation voltage value and the second operation voltage value to obtain a voltage modulus, and to perform operations based on the first operation current value and the second operation current value to obtain a current modulus, and to perform operations based on the voltage modulus and the current modulus to obtain an impedance modulus of the load.

4. The load impedance acquisition device according to claim 3, characterized in that: The voltage modulus is the ratio of the square root of the sum of the square of the first operating voltage value and the square of the second operating voltage value to a constant 2; The current modulus is the ratio of the square root of the sum of the square of the first operating current value and the square of the second operating current value to a constant 2; The impedance modulus of the load is a ratio of the voltage modulus to the current modulus.

5. The load impedance acquisition device according to claim 1, characterized in that: The load impedance acquisition device also includes an angle acquisition unit and a third operation unit; The angle acquisition unit is connected between the sampling unit and the third operation unit, and the angle acquisition unit is used to acquire the waveform phase angle between the voltage waveform signal and the current waveform signal; The third operation unit is connected to the second operation unit, and is used for performing operation according to the impedance modulus value of the load and the waveform phase angle to obtain the impedance value of the load.

6. The load impedance acquisition device according to claim 5, characterized in that: The impedance value of the load includes a real part and an imaginary part, and the impedance value of the load is the sum of the real part of the impedance value of the load and the imaginary part of the impedance value of the load; The real part of the impedance value of the load is the product of the impedance modulus of the load and the cosine value of the waveform phase angle, and the imaginary part of the impedance value of the load is the product of the impedance modulus of the load, the sine value of the waveform phase angle and the imaginary unit.

7. The load impedance acquisition device according to claim 5, characterized in that: The angle acquisition unit includes a phase detector and a table lookup unit, and the phase detector and the table lookup unit are sequentially connected between the sampling unit and the third operation unit; The phase detector is used to obtain a phase voltage value according to the voltage waveform signal and the current waveform signal; The table lookup device is used to determine the waveform phase angle corresponding to the phase voltage value according to the corresponding relationship between multiple preset waveform phase angles and multiple phase voltage values.

8. The load impedance acquisition device according to claim 1, characterized in that: The sampling unit includes a first signal acquisition circuit, a second signal acquisition circuit, a first sampler and a second sampler, the first signal acquisition circuit and the second signal acquisition circuit are both used to connect to the output path of the RF power supply, the first sampler is connected between the first signal acquisition circuit and the first operation unit, and the second sampler is connected between the second signal acquisition circuit and the first operation unit; The first signal acquisition circuit is used to acquire the voltage waveform signal, and the first sampler is used to sample the voltage waveform signal at a time interval of 1 / 4 of the cycle time of the radio frequency signal to obtain the four sampled voltage values; The second signal acquisition circuit is used to acquire the current waveform signal, and the second sampler is used to sample the current waveform signal at a time interval of 1 / 4 of the cycle time of the radio frequency signal to obtain the four sampled current values.

9. The load impedance acquisition device according to claim 1, characterized in that: The first operation unit is further used to reduce the four sampled voltage values ​​and then perform two-by-two operations on the four reduced sampled voltage values, and to reduce the four sampled current values ​​and then perform two-by-two operations on the four reduced sampled current values.

10. A radio frequency power supply system, characterized in that: It comprises a radio frequency power supply and a load impedance acquisition device as described in any one of claims 1 to 9.

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