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 signal acquisition unit, an impedance value acquisition unit and a module value operation unit. The signal acquisition unit is used for being connected with an output path of a radio frequency power supply so as to acquire a voltage waveform signal and a current waveform signal of a radio frequency signal output by the radio frequency power supply to a load; the impedance value acquisition unit is used for acquiring four sampling impedance values according to the voltage waveform signal and the current waveform signal, the four sampling impedance values are impedance values corresponding to four moments with 1 / 4 of the cycle time of the radio frequency signal as a time interval within a preset time length, and the preset time length is equal to one cycle time of the radio frequency signal; and the module value operation unit is connected with the impedance value acquisition unit and is used for performing operation according to the four sampling impedance values so as to obtain an impedance module value of the load. 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 signal acquisition unit, an impedance value acquisition unit and a modulus value operation unit. The signal acquisition unit is used to connect to the output path of the RF power supply to obtain the voltage waveform signal and the current waveform signal of the RF signal output by the RF power supply to the load. The impedance value acquisition unit is used to obtain four sampled impedance values ​​according to the voltage waveform signal and the current waveform signal, wherein the four sampled impedance values ​​are impedance values ​​corresponding to four moments at a time interval of 1 / 4 of the cycle time of the RF signal within a preset time length, wherein the preset time length is equal to one cycle time of the RF signal. The modulus value operation unit is connected to the impedance value acquisition unit, and the modulus value operation unit is used to perform operations according to the four sampled impedance values ​​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 impedance value acquisition unit includes a waveform operation unit and a sampling unit. The waveform operation unit is connected to the signal acquisition unit, and the waveform operation unit is used to perform operations based on the voltage waveform signal and the current waveform signal to obtain the impedance waveform signal of the load. The sampling unit is connected to the waveform operation unit, and the sampling unit is used to sample the impedance waveform signal at a time interval of 1 / 4 of the cycle time of the RF signal within the preset time length to obtain the four sampled impedance values ​​accordingly.

[0006] In a possible implementation manner, the waveform operation unit is used to perform a division operation on the voltage waveform signal and the current waveform to obtain the impedance waveform signal.

[0007] In a possible implementation, the four sampled impedance values ​​include a first sampled impedance value, a second sampled impedance value, a third sampled impedance value, and a fourth sampled impedance value obtained by sequentially sampling the impedance waveform signal at a time interval of 1 / 4 of the cycle time of the RF signal. The modulus operation unit is used to perform a subtraction operation on the first sampled impedance value and the third sampled impedance value to obtain a first operational impedance value, and to perform a subtraction operation on the second sampled impedance value and the fourth sampled impedance value to obtain a second operational impedance value.

[0008] In a possible implementation manner, the impedance modulus is a ratio of the square root of the sum of the square of the first operational impedance value and the square of the second operational impedance value to a constant 2.

[0009] In a possible implementation, the load impedance acquisition device further includes an angle acquisition unit and an impedance value calculation unit. The angle acquisition unit is connected between the signal acquisition unit and the impedance value calculation unit, and the angle acquisition unit is used to obtain the waveform phase angle between the voltage waveform signal and the current waveform signal. The impedance value calculation unit is also connected to the modulus value calculation unit, and the impedance value calculation unit is used to perform calculations based on the impedance modulus value of the load and the waveform phase angle to obtain the impedance value of the load.

[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 signal acquisition unit and the impedance value calculation 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 the preset multiple waveform phase angles and the multiple phase voltage values.

[0011] In a possible implementation, the sampling unit includes a first sampler connected between the waveform operation unit and the modulus operation unit, wherein the first sampler is used to sample the impedance waveform signal at a time interval of 1 / 4 of the cycle time of the radio frequency signal to obtain the four sampled impedance values.

[0012] In a possible implementation, the signal acquisition unit includes a first signal acquisition circuit and a second signal acquisition circuit, and the first signal acquisition circuit and the second signal acquisition circuit are used to be connected to the output path of the RF power supply. The first signal acquisition circuit is used to acquire the voltage waveform signal, and the second signal acquisition circuit is used to acquire the current waveform signal.

[0013] In a second aspect, a radio frequency power supply system is also provided, the radio frequency power supply system comprising a radio frequency power supply and a load impedance acquisition device. The load impedance acquisition device comprises a signal acquisition unit, an impedance value acquisition unit and a modulus value operation unit. The signal acquisition 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. The impedance value acquisition unit is used to obtain four sampled impedance values ​​according to the voltage waveform signal and the current waveform signal, wherein the four sampled impedance values ​​are impedance values ​​corresponding to four moments at a time interval of 1 / 4 of the cycle time of the radio frequency signal within a preset time length, wherein the preset time length is equal to one cycle time of the radio frequency signal. The modulus value operation unit is connected to the sampling unit, and the modulus value operation unit is used to perform operations according to the four sampled impedance values ​​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 RF power supply system of the present application obtain four sampled impedance values ​​at a time interval of 1 / 4 of the cycle time of the RF signal in one cycle time of the RF signal by setting an impedance value acquisition unit according to a voltage waveform signal and a current waveform signal, and perform calculations based on the four sampled impedance values ​​by setting a modulus value calculation unit, so as to quickly calculate the impedance modulus value of the load, 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 is a schematic diagram of a load impedance acquisition unit in an embodiment of the present application.

[0018] Figure 3 It is a schematic diagram of the load impedance acquisition device in another embodiment of the present application.

[0019] Figure 4 Schematic diagram of an angle acquisition unit in an embodiment of the present application.

[0020] Figure 5 is a schematic diagram of a sampling unit in an embodiment of the present application.

[0021] Figure 6 Schematic diagram of a signal acquisition unit in an embodiment of the present application.

[0022] Figure 7 Schematic diagram of a modulus calculation unit in an embodiment of the present application.

[0023] Figure 8 is a schematic diagram of a radio frequency power supply system in an embodiment of the present application.

[0024] Description of the accompanying drawings: 1000, RF power supply system, RF, RF power supply, RFS, RF signal, 10, load impedance acquisition device, 100, signal acquisition unit, Vs, voltage waveform signal, 110, first signal acquisition circuit, 120, second signal acquisition circuit, 200, impedance value acquisition unit, 210, waveform operation unit, Zs, impedance waveform signal, 220, sampling unit, Zf, four sampled impedance values, Zs1, first sampled impedance value, Zs2, second sampled impedance value, Zs3, third sampled impedance value, Zs 4. Fourth sampling impedance value, 300. Modulus value operation unit, 310. First subtractor, Zo1. First operational impedance value, 320. Second subtractor, Zo2. Second operational impedance value, 330. Modulus value operation module, 340. Second converter, 350. De-value module, |Z|. Impedance modulus value, 400. Angle acquisition unit, 410. Phase detector, Vps. Phase voltage signal, 420. First converter, Vp. Phase voltage value, 430. Look-up table, θ. Waveform phase angle, 500. Impedance value operation unit, RL. Load. DETAILED DESCRIPTION

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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 1 As shown, the present application provides a load impedance acquisition device 10, which includes a signal acquisition unit 100, an impedance value acquisition unit 200, and a modulus value operation unit 300. The signal acquisition unit 100 is used to connect to the output path of the radio frequency power supply RF to obtain the voltage waveform signal Vs and the current waveform signal of the radio frequency signal RFS output by the radio frequency power supply RF to the load RL. The impedance value acquisition unit 200 is used to obtain four sampled impedance values ​​Zf according to the voltage waveform signal Vs and the current waveform signal, wherein the four sampled impedance values ​​Zf are impedance values ​​corresponding to four moments with a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS within a preset time length, wherein the preset time length is equal to one cycle time of the radio frequency signal RFS. The modulus value operation unit 300 is connected to the impedance value acquisition unit 200, and the modulus value operation unit 300 is used to perform operations according to the four sampled impedance values ​​Zf to obtain the impedance modulus value |Z| of the load RL. Wherein, the waveform of the voltage waveform signal Vs and the waveform of the current waveform signal are both sine waves.

[0030] Therefore, the load impedance acquisition device 10 in the present application obtains four sampled impedance values ​​Zf at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS in one cycle time of the radio frequency signal RFS by setting the impedance value acquisition unit 200 according to the voltage waveform signal Vs and the current waveform signal, and performs calculations based on the four sampled impedance values ​​Zf by setting the modulus value calculation unit 300, so as to quickly calculate the impedance modulus value |Z| of the load RL, quickly determine the impedance condition of the load RL, and quickly complete impedance matching to achieve the best output effect.

[0031] The current waveform signal 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.

[0032] The waveform of the voltage waveform signal Vs and the waveform of the current waveform signal may both be sine waves or cosine waves.

[0033] 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.

[0034] In one or more embodiments, the impedance value acquisition unit 200 may be used to acquire four sampled voltage values ​​according to the voltage waveform signal Vs, and acquire four sampled current values ​​according to the current waveform signal, and acquire four sampled impedance values ​​Zf according to the four sampled voltage values ​​and the four sampled current values. The four sampled voltage values ​​and the four sampled current values ​​are voltage values ​​and current values ​​corresponding to four moments with a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS within a preset time length, so that the four sampled impedance values ​​Zf are impedance values ​​corresponding to four moments with a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS within a preset time length.

[0035] Furthermore, the four sampling impedance values ​​Zf are quotients of the corresponding four sampling voltage values ​​and four sampling current values.

[0036] See also Figure 2 , Figure 2 FIG. 1 is a schematic diagram of a load impedance acquisition unit in an embodiment of the present application. Figure 2As shown, the impedance value acquisition unit 200 includes a waveform operation unit 210 and a sampling unit 220. The waveform operation unit 210 is connected to the signal acquisition unit 100, and the waveform operation unit 210 is used to perform operations according to the voltage waveform signal Vs and the current waveform signal to obtain the impedance waveform signal Zs of the load RL. The sampling unit 220 is connected to the waveform operation unit 210, and the sampling unit 220 is used to sample the impedance waveform signal Zs 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 corresponding sampled impedance values ​​Zf.

[0037] Therefore, the load impedance acquisition device 10 in the present application, by setting the waveform operation unit 210 to first operate the voltage waveform signal Vs and the current waveform signal to obtain the impedance waveform signal Zs of the load RL, and then setting the sampling unit 220 to sample the impedance waveform signal Zs at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS within a preset time length, can more conveniently obtain the impedance modulus |Z| of the load RL.

[0038] That is, in some embodiments, the voltage waveform signal Vs and the current waveform signal may be first operated to obtain the impedance waveform signal Zs of the load RL, and then the sampling unit 220 may be set to sample the impedance waveform signal Zs at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS within a preset time length to obtain multiple sampled impedance values ​​Zf, for example, four sampled impedance values ​​Zf.

[0039] In one or more embodiments, the waveform operation unit 210 is used to perform a division operation on the voltage waveform signal Vs and the current waveform to obtain the impedance waveform signal Zs.

[0040] Therefore, the load impedance acquisition device 10 in the present application uses a division operation to obtain the impedance waveform signal Zs.

[0041] The waveform of the impedance waveform signal Zs is a sine wave.

[0042] Specifically, taking the example that the waveform of the voltage waveform signal Vs and the waveform of the current waveform signal are both cosine waves, the waveform of the impedance waveform signal Zs is also a cosine wave, then the first sampling impedance value Zs1, the second sampling impedance value Zs2, the third sampling impedance value Zs3 and the fourth sampling impedance value Zs4 can be |Z|×cos(ωt+x), |Z|×cos(ωt+x+π / 2), |Z|×cos(ωt+x+π) and |Z|×cos(ωt+x+3π / 2), respectively, where x is the initial phase angle of the impedance waveform signal Zs.

[0043] like Figure 1 , Figure 2As shown, the four sampled impedance values ​​Zf include a first sampled impedance value Zs1, a second sampled impedance value Zs2, a third sampled impedance value Zs3, and a fourth sampled impedance value Zs4 obtained by sequentially sampling the impedance waveform signal Zs at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS. The modulus operation unit 300 is used to perform a subtraction operation on the first sampled impedance value Zs1 and the third sampled impedance value Zs3 to obtain a first operational impedance value Zo1, and to perform a subtraction operation on the second sampled impedance value Zs2 and the fourth sampled impedance value Zs4 to obtain a second operational impedance value Zo2.

[0044] Therefore, the load impedance acquisition device 10 in the present application can calculate the first operational impedance value Zo1 according to the first sampled impedance value Zs1 and the third sampled impedance value Zs3, and can calculate the second operational impedance value Zo2 according to the second sampled impedance value Zs2 and the fourth sampled impedance value Zs4, thereby obtaining the first operational impedance value Zo1 and the second operational impedance value Zo2, and thus obtaining the impedance modulus |Z| of the load RL.

[0045] Specifically, the first operational impedance value Zo1 and the second operational impedance value Zo2 are |Z|×cos(ωt+x)-|Z|×cos(ωt+x+π) and |Z|×cos(ωt+x+π)-|Z|×cos(ωt+x+3π / 2), respectively.

[0046] In one or more embodiments, the impedance modulus |Z| is a ratio of the square root of the sum of the square of the first operational impedance value Zo1 and the square of the second operational impedance value Zo2 to a constant 2.

[0047] Therefore, the load impedance acquisition device 10 in the present application can obtain the impedance modulus value |Z| by performing the above operation on the first operational impedance value Zo1 and the second operational impedance value Zo2 according to the conversion formula related to the trigonometric function.

[0048] Specifically, the impedance modulus |Z| is the ratio of the square root of the sum of the square of the first operation voltage value and the square of the second operation voltage value to the constant 2, that is, |Z|=[√(Zo1 2 +Zo2 2 )] / 2.

[0049] See also Figure 3 , Figure 3 FIG. 1 is a schematic diagram of a load impedance acquisition device in another embodiment of the present application. Figure 3As shown, the load impedance acquisition device 10 further includes an angle acquisition unit 400 and an impedance value calculation unit 500. The angle acquisition unit 400 is connected between the signal acquisition unit 100 and the impedance value calculation 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. The impedance value calculation unit 500 is also connected to the modulus value calculation unit 300, and the impedance value calculation unit 500 is used to calculate 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.

[0050] 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 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] Please also read Figure 4 , Figure 4 FIG. 1 is a schematic diagram of an angle acquisition unit in an embodiment of the present application. Figure 3 , Figure 4As shown, the angle acquisition unit 400 includes a phase detector 410 and a table lookup 430, which are sequentially connected between the signal acquisition unit 100 and the impedance value calculation 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. 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.

[0056] 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 .

[0057] like Figure 4 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, 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.

[0058] Please also read Figure 5 , Figure 5 FIG. 1 is a schematic diagram of a sampling unit in an embodiment of the present application. Figure 1 , Figure 5 As shown, the sampling unit 220 includes a first sampler, which is connected between the waveform operation unit 210 and the modulus operation unit 300. The first sampler is used to sample the impedance waveform signal Zs at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS to obtain four sampled impedance values ​​Zf.

[0059] Therefore, the load impedance acquisition device 10 in the present application can obtain four corresponding sampled impedance values ​​Zf by setting the first sampler to sample the impedance waveform signal Zs at a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS.

[0060] The sampling frequency of the first sampler is 1 / 4 of the frequency of the radio frequency signal RFS.

[0061] Please also read Figure 6 , Figure 6 FIG. 1 is a schematic diagram of a signal acquisition unit in an embodiment of the present application. Figure 6 As shown, the signal acquisition unit 100 includes a first signal acquisition circuit 110 and a second signal acquisition circuit 120, and the first signal acquisition circuit 110 and the second signal acquisition circuit 120 are used to connect to the output path of the radio frequency power supply RF. The first signal acquisition circuit 110 is used to acquire the voltage waveform signal Vs, and the second signal acquisition circuit 120 is used to acquire the current waveform signal.

[0062] Therefore, the load impedance acquisition device 10 in the present application, by setting a first signal acquisition circuit 110 and a second signal acquisition circuit 120, can achieve the acquisition of the voltage waveform signal Vs and the current waveform signal of the radio frequency signal RFS output by the radio frequency power supply RF.

[0063] 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.

[0064] 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 a current waveform signal.

[0065] See also Figure 7 , Figure 7 FIG. 1 is a schematic diagram of a modulus calculation unit in an embodiment of the present application. Figure 7 As shown, the modulus operation unit 300 is further used to reduce the four sampling impedance values ​​Zf, and then perform operations on the reduced four sampling impedance values ​​Zf.

[0066] 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 sampled impedance values ​​Zf, the modulus calculation unit 300 can perform normal calculations on the four sampled impedance values ​​Zf, and the impedance value calculation unit 500 can also perform normal calculations.

[0067] Please also read Figure 1 .like Figure 1 , Figure 7As shown, the modulus operation unit 300 may include a first subtractor 310, a second subtractor 320, a reduction module 350 and a modulus operation module 330. The input ends of the first subtractor 310 and the second subtractor 320 are both connected to the signal acquisition unit 100 through the reduction module 350, and the output ends of the first subtractor 310 and the second subtractor 320 are both connected to the modulus operation module 330. Among them, the first subtractor 310 is used to perform a subtraction operation on the first sampling impedance value Zs1 and the third sampling impedance value Zs3 to obtain a first operational impedance value Zo1; the second subtractor 320 is used to perform a subtraction operation on the second sampling impedance value Zs2 and the fourth sampling impedance value Zs4 to obtain a second operational impedance value Zo2; the reduction module 350 is used to reduce the four sampling impedance values ​​Zf, and then perform operations on the reduced four sampling impedance values ​​Zf; the modulus operation module 330 is used to perform operations based on the first operational impedance value Zo1 and the second operational impedance value Zo2 to obtain the impedance modulus |Z| of the load RL.

[0068] In one or more embodiments, the decompression module 350 may include two capacitors, one end of the two capacitors is connected to the connection point between the signal acquisition unit 100 and the input ends of the first subtractor 310 and the second subtractor 320, and the other ends of the two capacitors are grounded.

[0069] like Figure 1 , Figure 7 As shown, the modulus value operation unit 300 may further include a second converter 340, the input end of the second converter 340 is connected to the output ends of the first subtractor 310 and the second subtractor 320, and the output end of the second converter 340 is used to output the impedance modulus value |Z| of the load RL. The second converter 340 is used to convert the operation results of the first subtractor 310 and the second subtractor 320 into the corresponding first operational impedance value Zo1 and the second operational impedance value Zo2.

[0070] In some embodiments, one or more of the waveform operation unit 210, the modulus operation unit 300, and the impedance value operation unit 500 may 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 micro control 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 operations can be completed.

[0071] 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.

[0072] See also Figure 8 , Figure 8 FIG. 1 is a schematic diagram of a radio frequency power supply system 1000 in an embodiment of the present application. Figure 8 As shown, the present application further provides a radio frequency power supply system 1000, and the radio frequency power supply system 1000 includes a radio frequency power supply RF and a load impedance acquisition device 10 in any of the aforementioned embodiments.

[0073] Please refer again Figure 1 .like Figure 1As shown, the load impedance acquisition device 10 includes a signal acquisition unit 100, an impedance value acquisition unit 200 and a modulus value operation unit 300. The signal acquisition unit 100 is used to connect to the output path of the radio frequency power supply RF to obtain the voltage waveform signal Vs and the current waveform signal of the radio frequency signal RFS output by the radio frequency power supply RF to the load RL. The impedance value acquisition unit 200 is used to obtain four sampled impedance values ​​Zf according to the voltage waveform signal Vs and the current waveform signal, wherein the four sampled impedance values ​​Zf are impedance values ​​corresponding to four moments with a time interval of 1 / 4 of the cycle time of the radio frequency signal RFS within a preset time length, wherein the preset time length is equal to one cycle time of the radio frequency signal RFS. The modulus value operation unit 300 is connected to the modulus value operation unit 300, and the modulus value operation unit 300 is used to perform operations according to the four sampled impedance values ​​Zf to obtain the impedance modulus value |Z| of the load RL. Among them, the waveform of the voltage waveform signal Vs and the waveform of the current waveform signal are both sine waves.

[0074] 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.

[0075] like Figure 1 , Figure 8 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.

[0076] 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.

[0077] 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 signal acquisition unit, used to be connected to the output path of the radio frequency power supply to obtain a voltage waveform signal and a current waveform signal of the radio frequency signal output by the radio frequency power supply to the load; An impedance value acquisition unit, configured to acquire four sampled impedance values ​​according to the voltage waveform signal and the current waveform signal, wherein the four sampled impedance values ​​are impedance values ​​corresponding to four moments at intervals of 1 / 4 of the cycle time of the radio frequency signal within a preset time length, wherein the preset time length is equal to one cycle time of the radio frequency signal; A modulus value calculation unit connected to the impedance value acquisition unit, the modulus value calculation unit is used to perform calculation according to the four sampled impedance values ​​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.

2. The load impedance acquisition device according to claim 1, characterized in that: The impedance value acquisition unit includes a waveform calculation unit and a sampling unit; The waveform operation unit is connected to the signal acquisition unit, and is used to perform operation according to the voltage waveform signal and the current waveform signal to obtain the impedance waveform signal of the load; The sampling unit is connected to the waveform operation unit, and is used to sample the impedance waveform signal at a time interval of 1 / 4 of the cycle time of the radio frequency signal within the preset time length, so as to obtain the four corresponding sampled impedance values.

3. The load impedance acquisition device according to claim 2, characterized in that: The waveform operation unit is used to perform a division operation on the voltage waveform signal and the current waveform to obtain the impedance waveform signal.

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

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

6. The load impedance acquisition device according to claim 2, characterized in that: The load impedance acquisition device also includes an angle acquisition unit and an impedance value calculation unit; The angle acquisition unit is connected between the signal acquisition unit and the impedance value calculation 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 impedance value calculation unit is connected to the modulus value calculation unit, and is used for performing calculation according to the impedance modulus value of the load and the waveform phase angle to obtain the impedance value of the load.

7. The load impedance acquisition device according to claim 6, 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 signal acquisition unit and the impedance value calculation 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 2, characterized in that: The sampling unit includes a first sampler, and the first sampler is connected between the waveform operation unit and the modulus value operation unit; The first sampler is used to sample the impedance waveform signal at a time interval of 1 / 4 of the cycle time of the radio frequency signal to obtain the four sampled impedance values.

9. The load impedance acquisition device according to claim 1, characterized in that: The signal acquisition unit includes a first signal acquisition circuit and a second signal acquisition circuit, and the first signal acquisition circuit and the second signal acquisition circuit are used to be connected to the output path of the radio frequency power supply; The first signal acquisition circuit is used to acquire the voltage waveform signal, and the second signal acquisition circuit is used to acquire the current waveform signal.

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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