Voltage sampling circuit based on electric field coupling and radio frequency matcher

Abstract

The utility model provides a voltage sampling circuit based on electric field coupling and a radio frequency matcher. The voltage sampling circuit based on electric field coupling comprises a voltage sampling probe and an adjustable voltage dividing unit. The voltage sampling probe is used for acquiring a high-frequency high-voltage signal output by the radio frequency matcher through electric field coupling based on a distributed capacitor formed by the voltage sampling probe and sampling points of the radio frequency matcher, and outputting the acquired high-frequency high-voltage signal to the adjustable voltage dividing unit; and the adjustable voltage division unit is used for performing voltage division on the high-frequency and high-voltage signal by using the adjusted voltage division multiple after being triggered and adjusted, and outputting the high-frequency and high-voltage signal after voltage division to the processing module. According to the utility model, based on a distributed capacitor formed by the voltage sampling probe and the sampling points of the radio frequency matcher, an output voltage signal is obtained through electric field coupling, voltage sampling with electrical isolation is realized, and the problem of long installation and debugging time of the voltage sampling probe and the radio frequency matcher is solved by adjusting the voltage division multiple of the adjustable voltage division unit.

Description

Technical Field

[0001] This utility model relates to the field of radio frequency technology, and in particular to a voltage sampling circuit and radio frequency matching device based on electric field coupling. Background Technology

[0002] In radio frequency (RF) applications, matching units are crucial components for ensuring efficient power delivery, reducing reflection losses, and improving system efficiency. Accurately sampling the high voltages within the RF matching unit is a challenge, especially when monitoring and adjusting the matching state to adapt to changing load conditions is required.

[0003] Traditional high-voltage sampling techniques typically involve directly connecting resistors or capacitors to the high-voltage point, using voltage division to reduce the voltage to a measurable level, and then converting the signal to DC voltage for reading through rectification and filtering circuits. While this method is effective enough for some applications, it has a significant drawback: a lack of electrical isolation. Furthermore, the voltage values ​​obtained through non-contact sampling depend on the sampling distance. Debugging personnel need to spend considerable time continuously modifying and adjusting the sampling distance to match the processor's voltage acceptance range, ensuring that the sampled voltage values ​​can be processed correctly. When the voltage acceptance range cannot be changed, debugging personnel need to continuously adjust and determine the optimal sampling distance. Utility Model Content

[0004] The main purpose of this invention is to provide a voltage sampling circuit and radio frequency matching device based on electric field coupling, which aims to solve the problems of lack of electrical isolation and long debugging time in the voltage sampling of radio frequency matching devices in the prior art.

[0005] To achieve the above objectives, this utility model proposes a voltage sampling circuit and an RF matching unit based on electric field coupling. The voltage sampling circuit based on electric field coupling is applied to an RF matching unit with a processing module. The voltage sampling circuit based on electric field coupling includes: a voltage sampling probe and an adjustable voltage divider unit.

[0006] The distance between the voltage sampling probe and the sampling point of the RF matching unit is within a preset sampling distance range. The voltage sampling probe is also connected to the input terminal of the adjustable voltage divider unit. The output terminal of the adjustable voltage divider unit is connected to the processing module.

[0007] The voltage sampling probe is used to obtain the high-frequency high-voltage signal output by the radio frequency matching device through electric field coupling based on the distributed capacitance formed by the voltage sampling probe and the sampling point of the radio frequency matching device, and output the obtained high-frequency high-voltage signal to the adjustable voltage divider unit.

[0008] The adjustable voltage divider unit is used to divide the high-frequency high-voltage signal using the adjusted voltage division multiple after being triggered for adjustment, and output the divided high-frequency high-voltage signal to the processing module.

[0009] Optionally, the number of voltage sampling probes is multiple, and the voltage sampling probes are distributed at preset intervals.

[0010] Optionally, the voltage sampling circuit based on electric field coupling further includes: a rectification unit and a filtering unit;

[0011] The input terminal of the rectifier unit is connected to the voltage sampling probe, and the output terminal is connected to the input terminal of the filter unit; the output terminal of the filter unit is connected to the input terminal of the adjustable voltage divider unit.

[0012] The sampling probe is used to output the acquired high-frequency high-voltage signal to the rectifier unit.

[0013] The rectifier unit is used to rectify the high-frequency high-voltage signal and output the rectified high-frequency high-voltage signal to the filter unit.

[0014] The filtering unit is used to filter the rectified high-frequency high-voltage signal and output the filtered high-frequency high-voltage signal to the adjustable voltage divider unit.

[0015] The adjustable voltage divider unit is used to divide the filtered high-frequency high-voltage signal using the adjusted voltage division multiple after being triggered for adjustment, and output the divided high-frequency high-voltage signal to the processing module.

[0016] Optionally, the number of rectifier units, filter units, and adjustable voltage divider units are all multiple, and the voltage sampling probe, rectifier unit, filter unit, and adjustable voltage divider unit are connected one-to-one to form multiple connection groups; the output terminals of the multiple adjustable voltage divider units are connected to the processing module to output multiple high-frequency high-voltage signals after rectification, filtering, and voltage division to the processing module.

[0017] Optionally, the rectifier unit includes: a first diode, a second diode, and a first resistor;

[0018] The anode of the first diode is connected to the voltage sampling probe, and the cathode is connected to the input terminal of the filter unit; the anode of the second diode is grounded, and the cathode is connected to the voltage sampling probe; the first resistor is connected in parallel with the second diode.

[0019] Optionally, the filtering unit includes: a first capacitor, a first inductor, and a second capacitor;

[0020] The first terminal of the first capacitor and the second terminal of the first inductor are connected to the output terminal of the rectifier unit, and the first terminal of the first inductor and the first terminal of the second capacitor are connected to the input terminal of the adjustable voltage divider unit; the second terminals of the first capacitor and the second terminal of the second capacitor are grounded.

[0021] Optionally, the adjustable voltage divider unit includes: an adjustable potentiometer and a third capacitor;

[0022] The second fixed terminal of the adjustable potentiometer is connected to the output terminal of the filter unit, the first fixed terminal is grounded, and the movable terminal is connected to the processing module; the third capacitor is connected in parallel between the first fixed terminal and the movable terminal.

[0023] Optionally, the voltage sampling probe is circular or square.

[0024] This invention also proposes an RF matching device, which includes the voltage sampling circuit based on electric field coupling.

[0025] This invention proposes a voltage sampling circuit and an RF matching unit based on electric field coupling. The voltage sampling circuit based on electric field coupling is applied to an RF matching unit with a processing module. The voltage sampling circuit based on electric field coupling includes: a voltage sampling probe and an adjustable voltage divider unit; the interval between the voltage sampling probe and the sampling point of the RF matching unit is within a preset sampling distance range; the voltage sampling probe is also connected to the input terminal of the adjustable voltage divider unit; the output terminal of the adjustable voltage divider unit is connected to the processing module; the voltage sampling probe is used to acquire the high-frequency high-voltage signal output by the RF matching unit through electric field coupling based on the distributed capacitance formed by the voltage sampling probe and the sampling point of the RF matching unit, and outputs the acquired high-frequency high-voltage signal to the adjustable voltage divider unit; the adjustable voltage divider unit is used to divide the high-frequency high-voltage signal using the adjusted voltage division multiple after being triggered for adjustment, and outputs the divided high-frequency high-voltage signal to the processing module. This invention utilizes the distributed capacitance formed by the sampling points of the voltage sampling probe and the RF matching unit to obtain the output voltage signal through electric field coupling, thereby achieving voltage sampling under electrically isolated conditions. Furthermore, by adjusting the voltage division factor of the adjustable voltage divider unit, it solves the problem of the need for precise installation of the voltage sampling probe and the RF matching unit, which results in long installation and debugging times. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the first embodiment of the voltage sampling circuit based on electric field coupling of this utility model;

[0028] Figure 2 This is a schematic diagram of the equivalent structure of multiple voltage sampling probes and the sampling points of the radio frequency matching unit in the second embodiment of the voltage sampling circuit based on electric field coupling of this utility model;

[0029] Figure 3 This is a schematic diagram of the second embodiment of the voltage sampling circuit based on electric field coupling of this utility model;

[0030] Figure 4 This is a schematic diagram of the third embodiment of the voltage sampling circuit based on electric field coupling of this utility model.

[0031] Explanation of icon numbers:

[0032]

[0033] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0034] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0035] It should be noted that all directional indicators (such as up, down, left, right, etc.) in the embodiments of this utility model are not explicitly stated.

[0036] (Front, back, etc.) are only used to explain the relative positional relationship and movement of the components in a specific posture (as shown in the attached figure). If the specific posture changes, the directional indication will also change accordingly.

[0037] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0038] Furthermore, in this utility model, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0039] The first embodiment of this utility model provides a voltage sampling circuit based on electric field coupling, referring to... Figure 1 As shown, Figure 1 This is a schematic diagram of the first embodiment of the voltage sampling circuit based on electric field coupling of this utility model. The voltage sampling circuit based on electric field coupling is applied to an RF matching unit with a processing module. The voltage sampling circuit based on electric field coupling includes: a voltage sampling probe 10 and an adjustable voltage divider unit 20;

[0040] The distance between the voltage sampling probe 10 and the sampling point of the RF matching unit is within a preset sampling distance range. The voltage sampling probe 10 is also connected to the input terminal of the adjustable voltage divider unit 20; the output terminal of the adjustable voltage divider unit 20 is connected to the processing module.

[0041] The voltage sampling probe 10 is used to obtain the high-frequency high-voltage signal output by the RF matching device through electric field coupling based on the distributed capacitance formed by the voltage sampling probe 10 and the sampling point of the RF matching device, and output the obtained high-frequency high-voltage signal to the adjustable voltage divider unit 20.

[0042] The adjustable voltage divider unit 20 is used to divide the high-frequency high-voltage signal using the adjusted voltage division multiple after being triggered for adjustment, and output the divided high-frequency high-voltage signal to the processing module.

[0043] It should be noted that the voltage sampling probe 10 is part of a voltage sampling circuit based on electric field coupling. Specifically, the spacing between the voltage sampling probe 10 and the sampling point of the RF matching unit causes a distributed capacitance to form between them under the influence of the electric field. It is easy to understand that both the voltage sampling probe 10 and the RF matching unit sampling point are conductors. The spacing between the voltage sampling probe 10 and the RF matching unit sampling point allows the sampling probe to capture high-voltage signals through electric field coupling without directly contacting the high-voltage point. This design fully utilizes electrical clearance as a physical isolation method to ensure the safety and electrical isolation of the sampling process. The RF matching unit sampling point can be the output terminal of the RF matching unit.

[0044] The voltage sampling probe 10 is used to obtain the high-frequency high-voltage signal output by the RF matching circuit through electric field coupling, based on the distributed capacitance formed by the voltage sampling probe 10 and the sampling points of the RF matching circuit. For example, when the RF matching circuit is working, a 13.56MHz high-frequency high-voltage source will be generated at the output.

[0045] Electric field coupling, also known as capacitive coupling or electrostatic coupling, is a mode of energy transfer caused by the presence of distributed capacitance (parasitic capacitance). The core principle is the transfer of high-frequency AC signals or energy through the interaction of electric fields between conductors. Essentially, it's based on the induction of charge or voltage on adjacent conductors by changes in the electric field, thus creating a coupling effect. Electric field coupling occurs because the parasitic capacitance formed between two conductors provides a low-impedance path, causing displacement current to flow in an unexpected path. For example, in a circuit, when two conductors (such as PCB wiring or heat sinks) are close together, even without direct contact, an equivalent capacitance is formed due to the electric field, causing high-frequency signals or interference currents to be transmitted through this path.

[0046] The voltage sampling probe 10 and the sampling point of the RF matching unit form a distributed capacitance. When the voltage at the sampling point of the RF matching unit changes over time (AC signal), a time-varying electric field is generated around it. According to the characteristics of capacitance, the changing voltage causes the charge on the two plates of the capacitor to change accordingly, thereby inducing an equal amount of opposite charge at the voltage sampling probe 10, forming an induced voltage. Assuming the capacitance of the distributed capacitance formed by the voltage sampling probe 10 and the sampling point of the RF matching unit is C, when the voltage change rate at the sampling point of the RF matching unit is... At that time, the current coupled to the voltage sampling probe 10 through the electric field is This current will generate an induced voltage at the voltage sampling probe 10, thus achieving energy transfer. Assuming the internal resistance of the voltage sampling probe 10 is R, the induced voltage (the voltage at the voltage sampling probe 10) is V2 = I × R. Where V1 is the voltage value at the sampling point of the RF matching unit, I is the current value coupled to the voltage sampling probe 10 by the electric field, and V2 is the voltage value at the voltage sampling probe 10.

[0047] The first embodiment of this utility model uses the distributed capacitance formed between the voltage sampling probe 10 and the radio frequency matching point to sense the high-frequency high-voltage signal of the radio frequency matching device at the voltage sampling probe 10 through electric field coupling, thereby solving the problem of lack of electrical isolation for voltage sampling of the radio frequency matching device in the prior art.

[0048] However, it should be noted that from the perspective of RF system control, the RF matching circuit outputs a voltage value, while the voltage sampling circuit samples and obtains the voltage value of the RF matching circuit as feedback, further adjusting the RF matching circuit to achieve a more accurate output voltage value. The voltage value obtained by the voltage sampling circuit ultimately needs to be processed by the controller. The controller has a limited range of voltages it can accept and recognize; for example, a microcontroller can generally only accept a maximum voltage input of 5V. The distance between the voltage sampling probe 10 and the sampling point of the RF matching circuit affects the voltage value at the voltage sampling probe 10, thus affecting the voltage value output to the controller. In practical applications, the distance between the voltage sampling probe 10 and the sampling point of the RF matching circuit is usually specified for the voltage acceptance range of a particular controller. However, during actual installation and debugging, to ensure the accurate distance between the voltage sampling probe 10 and the sampling point of the RF matching circuit, installation and debugging personnel need to spend a significant amount of time on debugging.

[0049] Assuming that the interval between the voltage sampling probe 10 and the sampling point of the RF matching device is designed to be a preset distance, in order to improve installation efficiency and save debugging time, it is necessary to allow for a deviation in the interval between the voltage sampling probe 10 and the sampling point of the RF matching device. By performing adjustable voltage division processing on the voltage at the voltage sampling probe 10, the error caused by the inaccurate interval between the voltage sampling probe 10 and the sampling point of the RF matching device can be corrected.

[0050] Based on the above concept, in this embodiment, the voltage sampling probe 10 is also connected to the input terminal of the adjustable voltage divider unit 20; the output terminal of the adjustable voltage divider unit 20 is connected to the processing module. The voltage sampling probe 10 acquires the high-frequency high-voltage signal output by the RF matching unit through electric field coupling and outputs the acquired high-frequency high-voltage signal to the adjustable voltage divider unit 20. The adjustable voltage divider unit 20, after being triggered for adjustment, uses the adjusted voltage division multiple to divide the high-frequency high-voltage signal and outputs the divided high-frequency high-voltage signal to the processing module.

[0051] It should be noted that the capacitance value of the distributed capacitance formed by the voltage sampling probe 10 and the sampling points of the RF matching unit is determined by its geometric structure, and the calculation formula is as follows: Where ε0 is the vacuum permittivity, ε r Let be the relative permittivity of the medium between conductors, A be the area of ​​the sampling points of the voltage sampling probe 10 and the RF matching device, and d be the distance between the sampling points of the voltage sampling probe 10 and the RF matching device. It can be seen that the capacitance value is inversely proportional to the distance: the closer the distance (the smaller d), the larger the capacitance value; the farther the distance (the larger d), the smaller the capacitance value. Combining this with the above formula for calculating the induced voltage (the voltage at the voltage sampling probe 10), we can obtain... Since the capacitance value is inversely proportional to the spacing distance, the voltage at the voltage sampling probe 10 is also inversely proportional to the spacing distance.

[0052] Assuming the initial distance between the designed voltage sampling probe 10 and the sampling point of the RF matching unit is d0, the voltage at the corresponding voltage sampling probe 10 is V. 20 After the voltage is divided by the initial voltage division factor T0 of the adjustable voltage divider unit 20, the output voltage V 30 To the processing module; during actual installation, the installation distance between the voltage sampling probe 10 and the sampling point of the RF matching unit is d1, and the corresponding voltage at the voltage sampling probe 10 is V. 21 It is easy to understand that the adjustable voltage divider unit 20 can be adjusted, and the adjusted voltage divider multiple T1 can be used to adjust the voltage V. 21 Perform voltage division to output voltage V 30 The processing module corrects errors caused by inaccurate spacing between the voltage sampling probe 10 and the RF matching unit's sampling points, allowing for deviations in the spacing between them, thus improving installation efficiency and saving debugging time. Additionally, the ratio of the adjusted voltage divider factor to the initial voltage divider factor is:

[0053] It should be noted that the RF matching unit outputs a high-frequency, high-voltage signal. The signal obtained through electric field coupling also exceeds the voltage range that the processor in the processing module can accept, so the adjustable voltage divider unit 20 is required for voltage division.

[0054] The distance between the voltage sampling probe 10 and the sampling point of the RF matching unit falls within the preset sampling distance range. It is easy to understand that the ratio of the adjusted voltage divider factor to the initial voltage divider factor is related to the ratio of the installation spacing to the initial spacing (as shown in the formula). Because the voltage sampling probe 10 and the RF matching unit sampling points form a distributed capacitance, there are requirements for the spacing between them. Furthermore, the adjustable voltage divider unit 20 has a limited voltage division range. Therefore, the spacing between the voltage sampling probe 10 and the RF matching unit sampling points is within a certain numerical range (preset sampling distance range). This preset sampling distance range can be obtained by researchers through experimental measurement. Generally, the preset sampling distance range is centered on the preset sampling distance (the initial distance between the designed voltage sampling probe 10 and the RF matching unit sampling points).

[0055] It is easy to understand that the preset sampling distance range is the installation range of the distance between the voltage sampling probe 10 and the RF matching point when the installation and commissioning personnel install the structure at the sampling point of the voltage sampling probe 10 and the RF matching point.

[0056] The first embodiment of this utility model proposes a voltage sampling circuit based on electric field coupling. This voltage sampling circuit is applied to an RF matching unit with a processing module. The electric field coupling voltage sampling circuit includes: a voltage sampling probe 10 and an adjustable voltage divider unit 20; the interval between the voltage sampling probe 10 and the sampling point of the RF matching unit is within a preset sampling distance range; the voltage sampling probe 10 is also connected to the input terminal of the adjustable voltage divider unit 20; the output terminal of the adjustable voltage divider unit 20 is connected to the processing module; the voltage sampling probe 10 is used to acquire the high-frequency high-voltage signal output by the RF matching unit through electric field coupling based on the distributed capacitance formed by the voltage sampling probe 10 and the sampling point of the RF matching unit, and outputs the acquired high-frequency high-voltage signal to the adjustable voltage divider unit 20; the adjustable voltage divider unit 20, after being triggered for adjustment, uses the adjusted voltage division multiple to divide the high-frequency high-voltage signal and outputs the divided high-frequency high-voltage signal to the processing module. This invention utilizes the distributed capacitance formed by the voltage sampling probe 10 and the sampling points of the RF matching unit to obtain the output voltage signal through electric field coupling, thereby achieving voltage sampling under electrically isolated conditions. Furthermore, by adjusting the voltage division factor of the adjustable voltage divider unit 20, it solves the problem of the voltage sampling probe 10 and the RF matching unit requiring precise installation and long installation and debugging time.

[0057] It is understood that the first embodiment proposed in this utility model also allows the product to be used normally if the installation personnel make an error in the assembly distance when assembling the voltage sampling probe 10 and the RF matching point. This can be achieved by making corresponding adjustments to the adjustable voltage divider unit 20.

[0058] Furthermore, in the second embodiment of this utility model, there are multiple voltage sampling probes 10, and each voltage sampling probe 10 is distributed at a preset interval.

[0059] It should be noted that, in the second embodiment of this utility model, multiple voltage sampling probes 10 are respectively connected to the input terminal of the adjustable voltage divider unit 20. Each voltage sampling probe 10 forms a distributed capacitance with the sampling point of the RF matching unit, and multiple distributed capacitances are connected in parallel. Figure 2 As shown, Figure 2 This is a schematic diagram showing the equivalent structure of multiple voltage sampling probes 10 and the sampling points of the radio frequency matching unit.

[0060] Additionally, it should be explained that there are multiple voltage sampling probes 10, and the voltage values ​​at multiple voltage sampling probes 10 are superimposed at the input of the adjustable voltage divider unit 20. Using multiple voltage sampling probes 10 ensures that the voltage sampling circuit can still function normally even if one of the voltage sampling probes 10 fails. Furthermore, the sampling signal acquired using multiple sampling probes is more stable than that acquired from a single point. Secondly, a suitable preset probe spacing can reduce mutual interference and improve the overall sampling quality and accuracy of the system. Too close a distance may lead to signal cross-interference.

[0061] Optionally, the shape of the voltage sampling probe 10 will affect the area of ​​its face with the sampling point of the RF matching device. The voltage sampling probe 10 can be a regular shape such as a circle or a square, which makes it easier for researchers to calculate the face area, obtain the correct distributed capacitance value, and then determine the appropriate sampling interval.

[0062] Optionally, such as Figure 3 As shown, the voltage sampling circuit based on electric field coupling also includes: a rectifier unit 30 and a filter unit 40;

[0063] The input terminal of the rectifier unit 30 is connected to the voltage sampling probe 10, and the output terminal is connected to the input terminal of the filter unit 40; the output terminal of the filter unit 40 is connected to the input terminal of the adjustable voltage divider unit 20.

[0064] The sampling probe is used to output the acquired high-frequency high-voltage signal to the rectifier unit 30;

[0065] The rectifier unit 30 is used to rectify the high-frequency high-voltage signal and output the rectified high-frequency high-voltage signal to the filter unit 40.

[0066] The filtering unit 40 is used to filter the rectified high-frequency high-voltage signal and output the filtered high-frequency high-voltage signal to the adjustable voltage divider unit 20.

[0067] The adjustable voltage divider unit 20 is used to divide the filtered high-frequency high-voltage signal using the adjusted voltage division multiple after being triggered for adjustment, and output the divided high-frequency high-voltage signal to the processing module.

[0068] It should be noted that the main function of the rectifier module is to convert the high-frequency, high-voltage alternating current (AC) signal captured by the sampling probe into a direct current (DC) signal. This process is essential for subsequent signal processing and analysis, as many electronic devices and signal processing algorithms require a stable DC signal to ensure accuracy and efficiency.

[0069] It should be noted that the addition of a filtering module further improves the voltage sampling circuit, making the entire system more efficient and accurate in processing high-frequency, high-voltage signals. The main function of the filtering module is to remove noise and unnecessary frequency components from the rectified signal, ensuring that the signal output to the voltage processing module is clear and usable.

[0070] It should be understood that although rectifier modules can convert AC signals to DC signals, some noise may be introduced or retained during the conversion process. Filtering modules can effectively remove this noise, ensuring signal quality. For specific monitoring and processing needs, only a specific frequency range of the signal may be required. Filtering modules can selectively retain or remove specific frequency components according to the design.

[0071] In the second embodiment of this utility model, although multiple voltage sampling probes 10 are provided to prevent some of the voltage sampling probes 10 from being damaged and causing the voltage sampling circuit to malfunction, the voltage values ​​of the multiple voltage sampling probes 10 are superimposed at the input terminal of the adjustable voltage divider unit 20. This makes it impossible to determine the specific damaged voltage sampling probe 10 or to acquire voltage data from multiple sampling points separately, thus facilitating the removal of abnormal voltage values.

[0072] Based on the above problems, in the third embodiment of this utility model, the number of rectifier units 30, the number of filter units 40, and the number of adjustable voltage divider units 20 are all multiple. The voltage sampling probe 10, rectifier units 30, filter units 40, and adjustable voltage divider units 20 are connected one-to-one to form multiple connection groups. The output terminals of the multiple adjustable voltage divider units 20 are connected to the processing module to output multiple high-frequency high-voltage signals after rectification, filtering, and voltage division to the processing module.

[0073] It is easy to understand that the number of voltage sampling probes 10, rectifier units 30, filter units 40, and adjustable voltage divider units 20 are the same. The voltage sampling probes 10, rectifier units 30, filter units 40, and adjustable voltage divider units 20 are connected one-to-one, forming multiple connection groups. Each connection group includes one voltage sampling probe 10, one rectifier unit 30, one filter unit 40, and one adjustable voltage divider unit 20. The high-frequency, high-voltage signal acquired by the voltage sampling probes 10 through electric field coupling is adjusted by the rectifier units 30, filter units 40, and adjustable voltage divider units 20 belonging to the same connection group before being output to the processing module. Correspondingly, the processing module has multiple voltage input ports for receiving the voltages output by the multiple adjustable voltage divider units 20.

[0074] In the third embodiment, the voltage values ​​at multiple voltage sampling probes 10 are processed by the rectifier unit 30, filter unit 40 and adjustable voltage divider unit 20 in the same connection group, and then output to the processing module. This provides a hardware basis for the processing module to identify damaged voltage sampling probes 10 and remove abnormal voltage values.

[0075] like Figure 4 As shown, in the fourth embodiment of this utility model, the rectifier unit 30 includes: a first diode D1, a second diode D2, and a first resistor R1;

[0076] The anode of the first diode D1 is connected to the voltage sampling probe 10, and the cathode is connected to the input terminal of the filter unit 40; the anode of the second diode D2 is grounded, and the cathode is connected to the voltage sampling probe 10; the first resistor R1 is connected in parallel with the second diode D2.

[0077] To clarify, the RF matching unit outputs a high-frequency, high-voltage AC signal, and correspondingly, the induced voltage at voltage sampling probe 10 is also an AC signal. The first diode D1 performs half-wave rectification on the AC signal. During the positive half-cycle of the AC signal, the signal passes through the first diode D1 to the input terminal of the filter unit 40. During the negative half-cycle, the signal is discharged to ground through the second diode D2 and the first resistor R1.

[0078] The filter unit 40 includes: a first capacitor C1, a first inductor L1, and a second capacitor C2;

[0079] The first terminal of the first capacitor C1 and the second terminal of the first inductor L1 are connected to the output terminal of the rectifier unit 30, and the first terminal of the first inductor L1 and the first terminal of the second capacitor C2 are connected to the input terminal of the adjustable voltage divider unit 20; the second terminals of the first capacitor C1 and the second terminals of the second capacitor C2 are grounded.

[0080] The first capacitor C1, the first inductor L1, and the second capacitor C2 form a π-type filter. If the rectifier unit 30 performs half-wave rectification, during the positive half-cycle of the output AC signal, the first capacitor C1 charges first, reaching the peak voltage of the AC signal. Simultaneously, a linearly increasing current flows through the first inductor L1, storing magnetic energy. As the current increases, the stored magnetic energy increases. The second capacitor C2 charges through the first inductor L1, and the voltage values ​​of the first capacitor C1 and the second capacitor C2 become equal. During the negative half-cycle of the AC signal, the rectifier unit 30 stops outputting, and the second capacitor C2 discharges. The magnetic energy stored in the first inductor L1 is converted into electrical energy and discharged in series with the voltage across the first capacitor C1. The filter unit 40 filters high-frequency ripple through the π-type filter.

[0081] The adjustable voltage divider unit 20 includes: an adjustable potentiometer AP and a third capacitor C3;

[0082] The second fixed terminal of the adjustable potentiometer AP is connected to the output terminal of the filter unit 40, the first fixed terminal is grounded, and the movable terminal is connected to the processing module; the third capacitor C3 is connected in parallel between the first fixed terminal and the movable terminal.

[0083] It should be noted that the adjustable potentiometer AP divides the voltage output from the filter unit 40. The voltage division factor is changed by altering the position of the movable terminal. It's easy to understand that current enters from the second fixed terminal of the adjustable potentiometer AP and flows out from the first fixed terminal and the movable terminal. Assuming the impedance between the first fixed terminal and the movable terminal is Z1, and the impedance between the first fixed terminal and the second fixed terminal is Z2, the voltage division factor is calculated as follows: Where B is the voltage division coefficient. One end of the third capacitor C3 is connected to the movable terminal and the processing module, and the other end is grounded; the third capacitor C3 is used to stabilize the voltage value after voltage division.

[0084] This invention also proposes a radio frequency matching device, which includes a voltage sampling circuit based on electric field coupling.

[0085] The specific structure of the voltage sampling circuit based on electric field coupling is as described in the above embodiments. Since this RF matching circuit adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, and will not be repeated here. The above are only optional embodiments of this utility model, and do not limit the patent scope of this utility model. All equivalent structural transformations made under the concept of this utility model using the content of this utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this utility model.

Claims

1. A voltage sampling circuit based on electric field coupling, characterized in that, The voltage sampling circuit based on electric field coupling is applied to an RF matching unit with a processing module. The voltage sampling circuit based on electric field coupling includes: a voltage sampling probe and an adjustable voltage divider unit. The distance between the voltage sampling probe and the sampling point of the RF matching unit is within a preset sampling distance range. The voltage sampling probe is also connected to the input terminal of the adjustable voltage divider unit. The output terminal of the adjustable voltage divider unit is connected to the processing module. The voltage sampling probe is used to obtain the high-frequency high-voltage signal output by the radio frequency matching device through electric field coupling based on the distributed capacitance formed by the voltage sampling probe and the sampling point of the radio frequency matching device, and output the obtained high-frequency high-voltage signal to the adjustable voltage divider unit. The adjustable voltage divider unit is used to divide the high-frequency high-voltage signal using the adjusted voltage division multiple after being triggered for adjustment, and output the divided high-frequency high-voltage signal to the processing module.

2. The voltage sampling circuit based on electric field coupling as described in claim 1, characterized in that, The voltage sampling probes are multiple, and each voltage sampling probe is distributed at a preset interval.

3. The voltage sampling circuit based on electric field coupling as described in claim 1, characterized in that, The voltage sampling circuit based on electric field coupling also includes: a rectification unit and a filtering unit; The input terminal of the rectifier unit is connected to the voltage sampling probe, and the output terminal is connected to the input terminal of the filter unit; the output terminal of the filter unit is connected to the input terminal of the adjustable voltage divider unit. The sampling probe is used to output the acquired high-frequency high-voltage signal to the rectifier unit; The rectifier unit is used to rectify the high-frequency high-voltage signal and output the rectified high-frequency high-voltage signal to the filter unit. The filtering unit is used to filter the rectified high-frequency high-voltage signal and output the filtered high-frequency high-voltage signal to the adjustable voltage divider unit. The adjustable voltage divider unit is used to divide the filtered high-frequency high-voltage signal using the adjusted voltage division multiple after being triggered for adjustment, and output the divided high-frequency high-voltage signal to the processing module.

4. The voltage sampling circuit based on electric field coupling as described in claim 3, characterized in that, The number of rectifier units, filter units, and adjustable voltage divider units are all multiple. The voltage sampling probe, rectifier unit, filter unit, and adjustable voltage divider unit are connected one-to-one to form multiple connection groups. The output terminals of the multiple adjustable voltage divider units are connected to the processing module to output multiple high-frequency high-voltage signals after rectification, filtering, and voltage division to the processing module.

5. The voltage sampling circuit based on electric field coupling as described in claim 3 or claim 4, characterized in that, The rectifier unit includes: a first diode, a second diode, and a first resistor; The anode of the first diode is connected to the voltage sampling probe, and the cathode is connected to the input terminal of the filter unit; the anode of the second diode is grounded, and the cathode is connected to the voltage sampling probe; the first resistor is connected in parallel with the second diode.

6. The voltage sampling circuit based on electric field coupling as described in claim 3 or claim 4, characterized in that, The filtering unit includes: a first capacitor, a first inductor, and a second capacitor; The first terminal of the first capacitor and the second terminal of the first inductor are connected to the output terminal of the rectifier unit, and the first terminal of the first inductor and the first terminal of the second capacitor are connected to the input terminal of the adjustable voltage divider unit; the second terminals of the first capacitor and the second terminal of the second capacitor are grounded.

7. The voltage sampling circuit based on electric field coupling as described in any one of claims 1 to 4, characterized in that, The adjustable voltage divider unit includes: an adjustable potentiometer and a third capacitor; The second fixed terminal of the adjustable potentiometer is connected to the output terminal of the filter unit, the first fixed terminal is grounded, and the movable terminal is connected to the processing module; the third capacitor is connected in parallel between the first fixed terminal and the movable terminal.

8. The voltage sampling circuit based on electric field coupling as described in any one of claims 1 to 4, characterized in that, The voltage sampling probe is circular or square.

9. A radio frequency matching device, characterized in that, The radio frequency matching unit includes a voltage sampling circuit based on electric field coupling as described in any one of claims 1 to 8.

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