Electromagnetic compatibility protection circuit, protection system and electrical equipment

Abstract

The invention discloses an electromagnetic compatibility protection circuit, a protection system and electrical equipment, and belongs to the field of electromagnetic compatibility. The electromagnetic compatibility protection circuit comprises an electromagnetic interference detection module, a signal processing module, a characteristic signal control module and an electromagnetic interference suppression module, and the electromagnetic interference detection module detects interference signals of different frequency bands through a plurality of sensors, so that the interference signals of each frequency band can be detected, subsequent interference processing is facilitated, and the interference suppression efficiency is improved. The signal processing module converts the interference signal into a digital signal, the characteristic signal control module can conveniently extract the characteristic information of the interference signal and generate a target control signal according to the characteristic information, and the electromagnetic interference suppression module can change own circuit parameters when receiving the target control signal so as to suppress the interference signal of the corresponding frequency band. Therefore, no matter how complex the environment is, the electromagnetic compatibility protection circuit can ensure the electromagnetic compatibility of the equipment, the universality is high, and the effect is good.

Description

Technical Field

[0001] The present application relates to the field of electromagnetic compatibility technology, and in particular, to an electromagnetic compatibility protection circuit, protection system, and electrical equipment. Background Art

[0002] With the rapid development of electronic technology, the use of household appliances is becoming increasingly widespread, and the electromagnetic environment is becoming increasingly complex. While these appliances generate electromagnetic interference during operation, they are also susceptible to external electromagnetic interference, which can lead to performance degradation, misoperation, and even damage. Therefore, electromagnetic compatibility (EMC) has become a critical consideration in household appliance design.

[0003] Currently, common EMC protection measures for household appliances include filtering, shielding, and grounding. However, these common protection measures are limited in versatility and have significant limitations. In certain complex electromagnetic environments, they are either ineffective or bulky. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present application provides an electromagnetic compatibility protection circuit, protection system, and electrical device to address common electromagnetic compatibility protection measures for household appliances, such as filtering, shielding, and grounding. However, these common protection measures have limited versatility and significant limitations. In certain complex electromagnetic environments, they are either ineffective or bulky.

[0005] The technical solution adopted by this application to solve its technical problems is:

[0006] In a first aspect, an electromagnetic compatibility protection circuit is provided, comprising: an electromagnetic interference detection module, a signal processing module, a characteristic signal control module, and an electromagnetic interference suppression module;

[0007] The electromagnetic interference detection module includes a plurality of sensors, each of which is used to detect interference signals in a frequency band;

[0008] The signal processing module is connected to the electromagnetic interference detection module, and the signal processing module converts the interference signal output by the electromagnetic interference detection module into a digital signal;

[0009] The characteristic signal control module is connected to the signal processing module, and is used to extract characteristic information of the digital signal and generate a corresponding target control signal according to the characteristic information, wherein the characteristic information includes at least one of the following: main frequency, harmonic frequency, frequency information, and frequency resolution;

[0010] The electromagnetic interference suppression module is connected to the characteristic signal control module, and the electromagnetic interference suppression module includes a variable circuit unit. The variable circuit unit is used to adjust the circuit parameters of the electromagnetic interference suppression module according to the target control signal. The circuit parameters include at least one of the following: capacitance, resistance and inductance.

[0011] Furthermore, the electromagnetic interference suppression module also includes an effect monitoring and feedback unit;

[0012] The effect monitoring and feedback unit is connected to the variable circuit unit. After the variable circuit unit adjusts the circuit parameters of the electromagnetic interference suppression module according to the control signal, the effect monitoring and feedback unit monitors the electromagnetic interference changes and control effects. When the preset requirements are not met, the variable circuit unit is controlled to adjust the circuit parameters of the electromagnetic interference suppression module.

[0013] Furthermore, the electromagnetic interference detection module includes: a signal amplification unit, a filtering unit, a data processing unit and a signal output unit;

[0014] The signal amplifying unit is connected to one of the sensors at a time, and is used to amplify the interference signal obtained by the currently connected target sensor;

[0015] The filtering unit is connected to the signal amplifying unit, and the filtering unit is used to filter the signal amplified by the signal amplifying unit;

[0016] The data processing unit is connected to the filtering unit, and the data processing unit processes the signal filtered by the filtering unit, wherein the processing includes modulation;

[0017] The signal output unit is connected to the data processing unit, and is used to transmit the processed signal of the data processing unit to the signal processing module.

[0018] Furthermore, the electromagnetic interference detection module further includes a frequency selection circuit;

[0019] The frequency selection circuit is connected to the data processing unit, and the data processing unit obtains the target detection frequency band of the target sensor; the target parameters of the frequency selection circuit are determined according to the target detection frequency band. Under the target parameters, the frequency selection circuit filters out signals with a frequency band of the target detection frequency band from the interference signals obtained by the target sensor.

[0020] Furthermore, the signal processing module includes a radio frequency amplifier, a bandpass filter, a mixer, an oscillator, an intermediate frequency filter, an A / D conversion unit, an envelope detection unit, a threshold detection unit and a digital signal processor;

[0021] The radio frequency amplifier is used to amplify the signal output by the electromagnetic interference detection module;

[0022] The bandpass filter is connected to the radio frequency amplifier, and is used to perform bandpass filtering on the signal amplified by the radio frequency amplifier;

[0023] The mixer is connected to the bandpass filter and the oscillator respectively, and the mixer is used to filter a specific component of the signal filtered by the bandpass filter;

[0024] The intermediate frequency filter is connected to the mixer, and the intermediate frequency filter is used to filter the signal of the specific component output by the mixer;

[0025] The intermediate frequency filter is also connected to the digital signal processor through the envelope detection unit and the threshold detection unit;

[0026] The A / D conversion unit is connected to the intermediate frequency filter, and the A / D conversion unit converts the signal output by the intermediate frequency filter into a digital signal;

[0027] The digital signal processor is connected to the oscillator, the A / D conversion unit and the threshold detection unit respectively; the digital signal processor is used to obtain the digital signal to be output to the characteristic signal control module based on the digital signal output by the A / D conversion unit, the signal output by the oscillator and the signal output by the threshold detection unit.

[0028] Furthermore, the characteristic signal control module includes a digital signal input unit, a characteristic extraction unit, a characteristic parameter evaluation and judgment unit, a characteristic control signal generation unit, and a control signal transmission and execution unit;

[0029] The digital signal input unit is used to receive the digital signal output by the signal processing module;

[0030] The feature extraction unit is connected to the digital signal input unit, and the feature extraction unit is used to extract feature information from the digital signal output by the digital signal;

[0031] The characteristic parameter evaluation and judgment unit is connected to the characteristic extraction unit, and is used to judge the preset range to which the characteristic information belongs, each preset range corresponding to a preset control signal;

[0032] The characteristic control signal generating unit is connected to the characteristic parameter evaluation and judgment unit, and the characteristic control signal generating unit is configured to use a preset control signal corresponding to a preset range to which the characteristic information belongs as a target control signal;

[0033] The control signal transmission and execution unit is connected to the characteristic control signal generation unit, and the control signal transmission and execution unit is used to transmit the target control signal to the electromagnetic interference suppression module.

[0034] Furthermore, the electromagnetic interference suppression module further includes a control signal input unit;

[0035] The control signal input unit is connected to the variable circuit unit; the control signal input unit is used to receive the target control signal output by the characteristic signal control module; so that the variable circuit unit adjusts the circuit parameters of the electromagnetic interference suppression module according to the target control signal.

[0036] Furthermore, the variable circuit unit includes: an adjustable variable capacitor array, an adjustable variable resistor array, and an adjustable variable resistor array;

[0037] The adjustable variable capacitor array is used to adjust the size and combination of the capacitors of the electromagnetic interference suppression module;

[0038] The adjustable variable resistor array is used to adjust the resistance size and combination of the electromagnetic interference suppression module;

[0039] The adjustable variable resistor array is used to adjust the size and combination of the inductance of the electromagnetic interference suppression module;

[0040] The adjustable variable capacitor array, the adjustable variable resistor array and the adjustable variable resistor array are independent of each other.

[0041] In a second aspect, an electromagnetic compatibility protection system is provided, comprising the above-mentioned electromagnetic compatibility protection circuit.

[0042] In a third aspect, an electrical device is provided, comprising the above-mentioned electromagnetic compatibility protection circuit.

[0043] Beneficial effects:

[0044] The technical solution of the present application provides an electromagnetic compatibility protection circuit, protection system and electrical equipment. The electromagnetic compatibility protection circuit includes an electromagnetic interference detection module, a signal processing module, a characteristic signal control module and an electromagnetic interference suppression module. The electromagnetic interference detection module detects interference signals of different frequency bands through multiple sensors, ensuring that interference signals of each frequency band can be detected so that the interference can be processed later. The signal processing module converts the interference signal into a digital signal, which facilitates the characteristic signal control module to extract the characteristic information of the interference signal and generate a target control signal based on the characteristic information. When the electromagnetic interference suppression module receives the target control signal, it can change its own circuit parameters to suppress the interference signal of the corresponding frequency band. In this way, no matter how complex the environment is, the electromagnetic compatibility protection circuit of the present application can ensure the electromagnetic compatibility of the equipment, with high versatility and good effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0046] Figure 1 This is a schematic diagram of an existing circuit provided by an embodiment of the present application;

[0047] Figure 2 This is a schematic diagram of an electromagnetic compatibility protection circuit structure provided by an embodiment of the present application;

[0048] Figure 3 This is a schematic diagram of the structure of an electromagnetic interference detection module provided in an embodiment of the present application;

[0049] Figure 4 This is a schematic diagram of the structure of a signal processing module provided in an embodiment of the present application;

[0050] Figure 5 This is a structural diagram of a characteristic signal control module provided in an embodiment of the present application;

[0051] Figure 6 This is a schematic diagram of the structure of an electromagnetic interference suppression module provided in an embodiment of the present application;

[0052] Figure 7 This embodiment of the present application provides Figure 1 Schematic diagram of low-frequency EMC test results of the circuit shown;

[0053] Figure 8 This embodiment of the present application provides Figure 2 Schematic diagram of low-frequency EMC test results of the circuit shown;

[0054] Figure 9 This embodiment of the present application provides Figure 1 Schematic diagram of high-frequency EMC test results of the circuit shown;

[0055] Figure 10 This embodiment of the present application provides Figure 2 Schematic diagram of high-frequency EMC test results of the circuit shown. DETAILED DESCRIPTION

[0056] To make the purpose, technical solutions, and advantages of this application more clear, the technical solutions of this application are described in detail below with reference to the accompanying drawings and examples. Obviously, the described embodiments are only some of the embodiments of this application, rather than all of them. Based on the embodiments in this application, all other implementation methods obtained by ordinary technicians in this field without making any creative work are within the scope of protection of this application.

[0057] In existing circuits, electromagnetic compatibility protection measures usually rely on relatively simple and single methods. Figure 1 As shown in Figure 1, it is common to use a single fixed capacitor, inductor, or resistor for filtering or impedance matching. For example, you may only place a fixed capacitor at a specific location in the circuit to filter out interference at a specific frequency.

[0058] This single-component protection approach has many obvious limitations and is not very versatile. For example, a single fixed capacitor has a relatively narrow filtering frequency range and can only suppress electromagnetic interference around a specific frequency. Inductors and resistors also have similar limitations when it comes to electromagnetic interference.

[0059] Due to the single nature of the electromagnetic compatibility protection measures in existing circuits, they perform poorly when facing diverse electromagnetic interference. This is specifically manifested in the following aspects:

[0060] 1. Poor frequency adaptability: Different electromagnetic interference has different frequency characteristics, and a single component cannot effectively filter and suppress a wide frequency range. For example, for high-frequency electromagnetic interference, a single fixed capacitor may not provide sufficient attenuation; for low-frequency interference, a single inductor may have limited effect.

[0061] 2. Weak amplitude adaptability: The amplitude of electromagnetic interference varies widely, and the single protection element in the existing circuit is difficult to flexibly adjust according to the size of the interference amplitude. As a result, it may not provide sufficient protection when facing strong interference, and may cause excessive suppression when facing weak interference.

[0062] 3. Inadequate adaptability to equipment and environments: Different types of equipment and operating environments generate electromagnetic interference with varying characteristics. Existing circuit protection measures often cannot be adjusted to suit the specificities of the equipment and changing environments, making it difficult to meet diverse needs.

[0063] 4. Difficulty in integration: Due to the use of single components and suboptimal layout, when integrating electromagnetic compatibility protection measures into complex circuit systems, problems such as space limitations and wiring difficulties may be encountered, affecting the performance and reliability of the overall circuit.

[0064] To solve the above problems, refer to Figure 2 , an embodiment of the present application provides an electromagnetic compatibility protection circuit, comprising: an electromagnetic interference detection module, a signal processing module, a characteristic signal control module, and an electromagnetic interference suppression module;

[0065] The electromagnetic interference detection module includes multiple sensors, each of which is used to detect interference signals in a frequency band. Because sensors of different types or ranges are suitable for detecting different frequency bands, using multiple sensors ensures that actual interference signals can be accurately detected.

[0066] Exemplarily, the sensor uses a loop antenna, a rod antenna, a magnetic field sensor, or the like.

[0067] like Figure 3 As shown, the electromagnetic interference detection module includes: a signal amplification unit, a filtering unit, a data processing unit and a signal output unit;

[0068] The signal amplification unit is connected to one of the sensors at a time, and is used to amplify the interference signal obtained by the currently connected target sensor; wherein, in order to reduce costs and ensure that the signal amplification unit can amplify the signal detected by each sensor, the signal amplification unit can be connected to each sensor in turn, that is, the signal amplification unit is only connected to one sensor at the same time. In one embodiment, a timing switching unit can be set, and a preset time length is set in the timing switching unit. Every preset time length, the timing switching unit automatically switches the next sensor to connect with the signal amplification unit and the sensor; if a timing switching unit is used, its preset time length must be set long enough to ensure that the signal amplification unit can amplify the detection signal of the sensor. In this way, when a sensor does not detect a signal, it will cause a waste of time. Therefore, in another embodiment, a signal detection unit is also included. The signal detection unit detects whether the sensor receives a signal. If the sensor does not receive it, the timing switching unit directly ignores the sensor when switching.

[0069] The filtering unit is connected to the signal amplifying unit, and the filtering unit is used to filter the signal amplified by the signal amplifying unit;

[0070] The data processing unit is connected to the filtering unit, and the data processing unit processes the signal filtered by the filtering unit, wherein the processing includes modulation;

[0071] Preferably, the electromagnetic interference detection module further includes a frequency selection circuit;

[0072] The frequency selection circuit is connected to the data processing unit, and the data processing unit obtains the target detection frequency band of the target sensor; the target parameters of the frequency selection circuit are determined according to the target detection frequency band. Under the target parameters, the frequency selection circuit filters out signals with a frequency band of the target detection frequency band from the interference signals obtained by the target sensor.

[0073] The signal output unit is connected to the data processing unit, and is used to transmit the processed signal of the data processing unit to the signal processing module.

[0074] The traditional detection scheme uses resistive voltage divider detection, but resistive voltage divider detection has disadvantages such as limited dynamic response sensitivity and accuracy of the detection signal and susceptibility to interference. In this embodiment, a variety of sensors such as loop antennas, rod antennas, and magnetic field sensors are selected, and a frequency selection circuit is configured at the same time to output signals to the signal processing module. The east-west response sensitivity is high and it is not easily interfered with.

[0075] The signal processing module is connected to the electromagnetic interference detection module, and the signal processing module converts the interference signal output by the electromagnetic interference detection module into a digital signal.

[0076] like Figure 4 As shown, the signal processing module includes a radio frequency amplifier, a bandpass filter, a mixer, an oscillator, an intermediate frequency filter, an A / D conversion unit, an envelope detection unit, a threshold detection unit and a digital signal processor;

[0077] The radio frequency amplifier is used to amplify the signal output by the electromagnetic interference detection module;

[0078] The bandpass filter is connected to the radio frequency amplifier, and is used to perform bandpass filtering on the signal amplified by the radio frequency amplifier;

[0079] The mixer is connected to the bandpass filter and the oscillator respectively, and the mixer is used to filter a specific component of the signal filtered by the bandpass filter;

[0080] The intermediate frequency filter is connected to the mixer, and the intermediate frequency filter is used to filter the signal of the specific component output by the mixer;

[0081] The intermediate frequency filter is further connected to the digital signal processor via the envelope detection unit and the threshold detection unit. The envelope detection unit is used to demodulate the signal and extract envelope information from it to reflect the strength and changing trend of the interference signal. The threshold detection unit is used to determine whether the signal exceeds a preset threshold value to identify significant electromagnetic interference.

[0082] The A / D conversion unit is connected to the intermediate frequency filter, and the A / D conversion unit converts the signal output by the intermediate frequency filter into a digital signal;

[0083] The digital signal processor is connected to the oscillator, the A / D conversion unit and the threshold detection unit respectively; the digital signal processor is used to obtain the digital signal to be output to the characteristic signal control module based on the digital signal output by the A / D conversion unit, the signal output by the oscillator and the signal output by the threshold detection unit.

[0084] The digital signal output by the A / D converter unit, received by the digital signal processor, undergoes RF amplification, bandpass filtering, mixing, and intermediate frequency filtering. The received oscillator signal provides a stable reference signal for synchronization. The threshold detection unit's threshold detection result determines whether the signal exceeds a preset interference threshold and outputs a high or low level. If the threshold is exceeded, a high level is generated; if it is not, a low level is generated.

[0085] In the embodiment of the present application, the signal processing module is configured with a radio frequency amplifier for the output frequency band of the detection module, combines a mixer and an oscillator to obtain the signal of the corresponding component, and outputs the corresponding signal through envelope detection; it replaces the traditional solution of the chip receiving the current change adjustment signal, and solves its shortcomings such as limited adaptability, susceptibility to noise, and high calibration difficulty.

[0086] The characteristic signal control module is connected to the signal processing module, and is used to extract characteristic information of the digital signal and generate a corresponding target control signal based on the characteristic information. The characteristic information includes at least one of the following: main frequency, harmonic frequency, frequency information, and frequency resolution.

[0087] Different frequencies require different filtering components. For example, low-frequency interference may require inductors to suppress it, while high-frequency interference may require capacitors to filter it out. Therefore, depending on the main frequency and the harmonic frequencies, different capacitor and inductor combinations need to be selected.

[0088] The amplitude of the interference signal also affects the control strategy. Strong interference may require greater attenuation, such as selecting a larger capacitor or inductor value. Weak interference may require more precise adjustments, such as adjusting the resistance of a variable resistor.

[0089] The magnitude of the signal energy determines the intensity of the control measures that need to be taken. For example, when the signal energy is high, a larger resistor value may be required to achieve sufficient attenuation; when the signal energy is low, a smaller resistor value may be required to avoid excessive attenuation.

[0090] The energy of the frequency components is different:

[0091] The energy distribution of different frequency components also affects the control strategy. For example, if a frequency component has a high energy percentage, it may require more attention and control; if the energy distribution is more even, a comprehensive control strategy can be adopted.

[0092] By comprehensively considering these parameters, a more accurate and effective control strategy can be developed to achieve efficient suppression of electromagnetic interference. This not only improves the performance of the system, but also enhances its adaptability and reliability.

[0093] like Figure 5 As shown, the characteristic signal control module includes a digital signal input unit, a characteristic extraction unit, a characteristic parameter evaluation and judgment unit, a characteristic control signal generation unit, and a control signal transmission and execution unit;

[0094] The digital signal input unit is used to receive the digital signal output by the signal processing module;

[0095] The feature extraction unit is connected to the digital signal input unit, and the feature extraction unit is used to extract feature information from the digital signal output by the digital signal;

[0096] The characteristic parameter evaluation and judgment unit is connected to the characteristic extraction unit, and is used to judge the preset range to which the characteristic information belongs, each preset range corresponding to a preset control signal;

[0097] The characteristic control signal generating unit is connected to the characteristic parameter evaluation and judgment unit, and the characteristic control signal generating unit is configured to use a preset control signal corresponding to a preset range to which the characteristic information belongs as a target control signal;

[0098] The control signal transmission and execution unit is connected to the characteristic control signal generation unit, and the control signal transmission and execution unit is used to transmit the target control signal to the electromagnetic interference suppression module.

[0099] In the embodiment of the present application, the characteristic signal control module adds multiple closely connected links such as feature extraction (main frequency, harmonic frequency, energy of frequency components, frequency resolution), characteristic parameter evaluation and judgment (parameter selection and comparison of threshold and standard value), control signal generation, and control signal transmission and execution; it solves the shortcomings of traditional signal control modules, such as incomplete feature extraction, poor adaptability, lack of flexibility in signal generation, and lack of coordination with other modules.

[0100] The electromagnetic interference suppression module is connected to the characteristic signal control module, and the electromagnetic interference suppression module includes a variable circuit unit. The variable circuit unit is used to adjust the circuit parameters of the electromagnetic interference suppression module according to the target control signal. The circuit parameters include at least one of the following: capacitance, resistance and inductance.

[0101] like Figure 6 As shown, the electromagnetic interference suppression module further includes a control signal input unit;

[0102] The control signal input unit is connected to the variable circuit unit; the control signal input unit is used to receive the target control signal output by the characteristic signal control module; so that the variable circuit unit adjusts the circuit parameters of the electromagnetic interference suppression module according to the target control signal.

[0103] As a preferred implementation of the present application, the electromagnetic interference suppression module further includes an effect monitoring and feedback unit;

[0104] The effect monitoring and feedback unit is connected to the variable circuit unit. After the variable circuit unit adjusts the circuit parameters of the electromagnetic interference suppression module according to the control signal, the effect monitoring and feedback unit monitors the electromagnetic interference changes and control effects. When the preset requirements are not met, the variable circuit unit is controlled to adjust the circuit parameters of the electromagnetic interference suppression module.

[0105] The electromagnetic interference change and control effect can be determined based on whether the interference signal obtained by the electromagnetic interference detection module has changed. If the previous electromagnetic interference signal disappears or weakens to a certain extent, it means that the control effect is good. If a new interference signal appears or the interference signal weakens but does not reach a certain extent, the variable circuit unit is re-controlled to adjust the circuit parameters of the electromagnetic interference suppression module.

[0106] Wherein, the variable circuit unit includes: an adjustable variable capacitor array, an adjustable variable resistor array and an adjustable variable resistor array;

[0107] The adjustable variable capacitor array is used to adjust the size and combination of the capacitors of the electromagnetic interference suppression module;

[0108] The adjustable variable resistor array is used to adjust the resistance size and combination of the electromagnetic interference suppression module;

[0109] The adjustable variable resistor array is used to adjust the size and combination of the inductance of the electromagnetic interference suppression module;

[0110] The adjustable variable capacitor array, the adjustable variable resistor array and the adjustable variable resistor array are independent of each other.

[0111] The electromagnetic interference suppression module design provided in the embodiments of the present application interfaces with the characteristic signal control module. It receives control signals from the characteristic signal control module in real time, switches variable circuit units, selects and adjusts the capacitor combination in the variable capacitor array and the inductor combination in the variable inductor array, controls the capacitor or inductor connection or disconnection of the circuit, and sets and adjusts the resistance value of the variable resistor array to achieve electromagnetic interference suppression. Simultaneously, it continuously monitors electromagnetic interference changes and control effects. If the expected effect is not achieved, timely feedback is provided to the control module to adjust the strategy, forming a closed-loop optimization. This solves the problems of traditional fixed adjustment solutions, such as only filtering out specific frequency interference, resonance issues, and poor versatility.

[0112] The core invention of this solution lies in the innovative introduction and improvement of electromagnetic interference detection, signal processing module, characteristic signal control module and electromagnetic interference suppression module based on the characteristics of electromagnetic signals.

[0113] In practical applications, various sensors, such as loop antennas, rod antennas, and magnetic field sensors, must be strategically placed around the interference source to ensure accurate detection of electromagnetic interference signals. These sensors transmit the signals to the signal processing module via a frequency-selective circuit. Within this module, an RF amplifier amplifies the input signal, while a mixer and oscillator work together to extract the signal of a specific component. Finally, detection is performed to obtain a clear signal output corresponding to the component with higher interference energy. This signal then passes through an intermediate frequency (IF) filter, a bandpass filter that only allows signals within the bandwidth of its center frequency to pass through. Detection and A / D conversion are then performed to obtain an accurate output signal.

[0114] The feature extraction phase of the characteristic signal control module conducts in-depth signal analysis, extracting key information such as the main frequency, harmonic frequencies, and the energy of frequency components. Next, the characteristic parameter evaluation and judgment phase compares these parameters with preset thresholds and standard values ​​to determine the appropriate control strategy. The control signal generation phase then generates the corresponding control signal and transmits it to the electromagnetic interference suppression module through the transmission and execution phase.

[0115] It should be noted that the control strategy refers to the formulation of corresponding control measures based on the detected electromagnetic interference characteristics to effectively suppress electromagnetic interference. Specifically, the control strategy includes the following steps:

[0116] 1. Feature extraction: Extract key features from the signals collected by the sensor, such as the main frequency, harmonic frequency, and energy of the frequency components. 2. Feature parameter evaluation and judgment: Compare the extracted feature parameters with the preset thresholds and standard values ​​to determine the appropriate control strategy. 3. Control signal generation: Generate the corresponding control signal based on the evaluation results, and pass the signal to the electromagnetic interference suppression module through the transmission and execution links. 4. Feedback and optimization: In the electromagnetic interference suppression module, adjustments are made based on the received control signal, and changes in electromagnetic interference and control effects are continuously monitored. If the expected effect is not achieved, timely feedback is provided to the feature signal control module for strategy adjustment, forming a closed-loop optimization.

[0117] Specific examples:

[0118] Assume that there is a household appliance whose electromagnetic interference detection module detects the following characteristic parameters:

[0119] Main frequency: 100MHz;

[0120] Harmonic frequency: 200MHz, 300MHz;

[0121] Signal energy: 100mV;

[0122] Energy of frequency components: The main frequency energy accounts for 60% of the total energy, 200MHz and 300MHz each account for 20%.

[0123] Based on these parameters, the following control strategies can be developed:

[0124] Frequency control:

[0125] Since the main frequency is 100 MHz, the capacitor combination in the capacitor array can be adjusted to select a capacitor value that can effectively filter out 100 MHz interference. For example, a 10 pF capacitor can be selected to achieve 100 MHz filtering.

[0126] Harmonic frequency control:

[0127] For the 200MHz and 300MHz harmonic frequencies, the inductor can be adjusted to be connected or disconnected to achieve suppression of these frequencies. For example, a 10μH inductor can be connected to achieve filtering of 200MHz and 300MHz.

[0128] Signal Energy Control:

[0129] If the signal energy is 100mV, the resistance value of the variable resistor array can be adjusted to control the signal energy. For example, setting the resistance value to 100Ω can achieve attenuation of a 100mV signal.

[0130] Energy control of frequency components:

[0131] The main frequency energy accounts for 60% of the total energy, while 200MHz and 300MHz each account for 20%. Based on these proportions, the capacitor and inductor combination can be adjusted to achieve comprehensive control of different frequency components. For example, a 100MHz main frequency can use a 10pF capacitor, and 200MHz and 300MHz can use 10μH inductors respectively.

[0132] In the electromagnetic interference suppression module, according to the received control signal, the variable circuit unit is switched to select the appropriate capacitor combination, decide whether to connect or disconnect the inductor, and adjust the resistance value of the variable resistor array. At the same time, the changes in electromagnetic interference and the control effect are continuously monitored, and timely feedback is given to the variable circuit part of the characteristic signal control module for strategy adjustment. The entire system achieves accurate detection, effective processing, precise control and efficient suppression of electromagnetic interference through the coordinated work of various modules. And in Figure 7 、 Figure 8 、 Figure 9 and Figure 10 The test results show that Figure 2 The EMC test results of the electromagnetic compatibility protection circuit shown in the figure show that the interference suppression effect is significantly better than that of the Figure 1 The circuit shown.

[0133] Furthermore, in actual circuit design, factors such as the rationality of wiring between modules and electromagnetic compatibility must be considered to ensure stable operation of the entire system. Furthermore, for different types of equipment and working environments, the parameters of each module can be optimized and adjusted according to specific needs to improve the system's adaptability and performance.

[0134] It should be noted that the present application does not limit the specific structure of each module and unit given. Those skilled in the art can set the specific circuit structure of each module and unit according to actual needs on the premise of realizing the functions of each module and unit mentioned above.

[0135] The electromagnetic compatibility protection circuit provided in the embodiment of the present application includes an electromagnetic interference detection module, a signal processing module, a characteristic signal control module and an electromagnetic interference suppression module. The electromagnetic interference detection module detects interference signals of different frequency bands through multiple sensors, ensuring that the interference signals of each frequency band can be detected so that the interference can be processed subsequently. The signal processing module converts the interference signal into a digital signal, which facilitates the characteristic signal control module to extract the characteristic information of the interference signal and generate a target control signal based on the characteristic information. When the electromagnetic interference suppression module receives the target control signal, it can change its own circuit parameters to suppress the interference signal of the corresponding frequency band. In this way, no matter how complex the environment is, the electromagnetic compatibility protection circuit of the present application can ensure the electromagnetic compatibility of the equipment, with high versatility and good effect.

[0136] Based on the same inventive concept, the present application also provides an electromagnetic compatibility protection system, including the electromagnetic compatibility protection circuit provided by the above embodiment.

[0137] The electromagnetic compatibility protection system provided by the embodiment of the present application includes the electromagnetic compatibility protection circuit provided by the above embodiment, and the electromagnetic compatibility protection circuit includes an electromagnetic interference detection module, a signal processing module, a characteristic signal control module and an electromagnetic interference suppression module. The electromagnetic interference detection module detects interference signals of different frequency bands through multiple sensors, ensuring that the interference signals of each frequency band can be detected so that the interference can be processed subsequently. The signal processing module converts the interference signal into a digital signal, which facilitates the characteristic signal control module to extract the characteristic information of the interference signal and generate a target control signal based on the characteristic information. When the electromagnetic interference suppression module receives the target control signal, it can change its own circuit parameters to suppress the interference signal of the corresponding frequency band. In this way, no matter how complex the environment is, the electromagnetic compatibility protection circuit of the present application can ensure the electromagnetic compatibility of the equipment, with high versatility and good effect.

[0138] Based on the same inventive concept, the present application also provides an electrical device, including the electromagnetic compatibility protection circuit provided by the above embodiment.

[0139] The electrical equipment provided in the embodiment of the present application includes the electromagnetic compatibility protection circuit provided in the above embodiment, and the electromagnetic compatibility protection circuit includes an electromagnetic interference detection module, a signal processing module, a characteristic signal control module and an electromagnetic interference suppression module. The electromagnetic interference detection module detects interference signals of different frequency bands through multiple sensors, ensuring that the interference signals of each frequency band can be detected so that the interference can be processed subsequently. The signal processing module converts the interference signal into a digital signal, which facilitates the characteristic signal control module to extract the characteristic information of the interference signal and generate a target control signal based on the characteristic information. When the electromagnetic interference suppression module receives the target control signal, it can change its own circuit parameters to suppress the interference signal of the corresponding frequency band. In this way, no matter how complex the environment is, the electromagnetic compatibility protection circuit of the present application can ensure the electromagnetic compatibility of the equipment, with high versatility and good effect.

[0140] It should be noted that, in the description of this application, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" refers to at least two.

[0141] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

Claims

1. An electromagnetic compatibility protection circuit, characterized in that: include: Electromagnetic interference detection module, signal processing module, characteristic signal control module and electromagnetic interference suppression module; The electromagnetic interference detection module includes a plurality of sensors, each of which is used to detect interference signals of a frequency band; The signal processing module is connected to the electromagnetic interference detection module, and the signal processing module converts the interference signal output by the electromagnetic interference detection module into a digital signal; The characteristic signal control module is connected to the signal processing module, and is used to extract characteristic information of the digital signal and generate a corresponding target control signal according to the characteristic information, wherein the characteristic information includes at least one of the following: main frequency, harmonic frequency, frequency information, and frequency resolution; The electromagnetic interference suppression module is connected to the characteristic signal control module, and the electromagnetic interference suppression module includes a variable circuit unit, which is used to adjust the circuit parameters of the electromagnetic interference suppression module according to the target control signal, and the circuit parameters include at least one of the following: capacitance, resistance and inductance.

2. The electromagnetic compatibility protection circuit according to claim 1, characterized in that: The electromagnetic interference suppression module also includes an effect monitoring and feedback unit; The effect monitoring and feedback unit is connected to the variable circuit unit. After the variable circuit unit adjusts the circuit parameters of the electromagnetic interference suppression module according to the control signal, the effect monitoring and feedback unit monitors the electromagnetic interference changes and control effects. When the preset requirements are not met, the variable circuit unit is controlled to adjust the circuit parameters of the electromagnetic interference suppression module.

3. The electromagnetic compatibility protection circuit according to claim 1, characterized in that: The electromagnetic interference detection module includes: a signal amplification unit, a filtering unit, a data processing unit and a signal output unit; The signal amplifying unit is connected to one of the sensors at a time, and the signal amplifying unit is used to amplify the interference signal acquired by the currently connected target sensor; The filtering unit is connected to the signal amplifying unit, and the filtering unit is used to filter the signal amplified by the signal amplifying unit; The data processing unit is connected to the filtering unit, and the data processing unit processes the filtered signal of the filtering unit, wherein the processing includes modulation; The signal output unit is connected to the data processing unit, and the signal output unit is used to transmit the processed signal of the data processing unit to the signal processing module.

4. The electromagnetic compatibility protection circuit according to claim 3, characterized in that: The electromagnetic interference detection module also includes a frequency selection circuit; The frequency selection circuit is connected to the data processing unit, and the data processing unit obtains the target detection frequency band of the target sensor; the target parameters of the frequency selection circuit are determined according to the target detection frequency band, and under the target parameters, the frequency selection circuit filters out the signal with the frequency band of the target detection frequency band from the interference signal obtained by the target sensor.

5. The electromagnetic compatibility protection circuit according to claim 1, characterized in that: The signal processing module includes a radio frequency amplifier, a bandpass filter, a mixer, an oscillator, an intermediate frequency filter, an A / D conversion unit, an envelope detection unit, a threshold detection unit and a digital signal processor; The radio frequency amplifier is used to amplify the signal output by the electromagnetic interference detection module; The bandpass filter is connected to the radio frequency amplifier, and the bandpass filter is used to perform bandpass filtering on the signal amplified by the radio frequency amplifier; The mixer is connected to the bandpass filter and the oscillator respectively, and the mixer is used to filter a specific component of the signal filtered by the bandpass filter; The intermediate frequency filter is connected to the mixer, and the intermediate frequency filter is used to filter the signal of the specific component output by the mixer; The intermediate frequency filter is also connected to the digital signal processor through the envelope detection unit and the threshold detection unit; The A / D conversion unit is connected to the intermediate frequency filter, and the A / D conversion unit converts the signal output by the intermediate frequency filter into a digital signal; The digital signal processor is connected to the oscillator, the A / D conversion unit and the threshold detection unit respectively; the digital signal processor is used to obtain the digital signal to be output to the characteristic signal control module based on the digital signal output by the A / D conversion unit, the signal output by the oscillator and the signal output by the threshold detection unit.

6. The electromagnetic compatibility protection circuit according to claim 1, characterized in that: The characteristic signal control module includes a digital signal input unit, a characteristic extraction unit, a characteristic parameter evaluation and judgment unit, a characteristic control signal generation unit and a control signal transmission and execution unit; The digital signal input unit is used to receive the digital signal output by the signal processing module; The feature extraction unit is connected to the digital signal input unit, and the feature extraction unit is used to extract feature information from the digital signal output by the digital signal; The characteristic parameter evaluation and judgment unit is connected to the characteristic extraction unit, and the characteristic parameter evaluation and judgment unit is used to judge the preset range to which the characteristic information belongs, and each preset range corresponds to a preset control signal; The characteristic control signal generating unit is connected to the characteristic parameter evaluation and judgment unit, and the characteristic control signal generating unit is used to use the preset control signal corresponding to the preset range to which the characteristic information belongs as the target control signal; The control signal transmission and execution unit is connected to the characteristic control signal generation unit, and the control signal transmission and execution unit is used to transmit the target control signal to the electromagnetic interference suppression module.

7. The electromagnetic compatibility protection circuit according to claim 1, characterized in that: The electromagnetic interference suppression module also includes a control signal input unit; The control signal input unit is connected to the variable circuit unit; the control signal input unit is used to receive the target control signal output by the characteristic signal control module; so that the variable circuit unit adjusts the circuit parameters of the electromagnetic interference suppression module according to the target control signal.

8. The electromagnetic compatibility protection circuit according to claim 1 or 7, characterized in that: The variable circuit unit includes: an adjustable variable capacitor array, an adjustable variable resistor array and an adjustable variable resistor array; The adjustable variable capacitor array is used to adjust the size and combination of the capacitors of the electromagnetic interference suppression module; The adjustable variable resistor array is used to adjust the resistance size and combination mode of the electromagnetic interference suppression module; The adjustable variable resistor array is used to adjust the size and combination of the inductance of the electromagnetic interference suppression module; The adjustable variable capacitor array, the adjustable variable resistor array and the adjustable variable resistor array are independent of each other.

9. An electromagnetic compatibility protection system, characterized in that: The electromagnetic compatibility protection circuit comprises the electromagnetic compatibility protection circuit described in any one of claims 1 to 8.

10. An electrical device, characterized in that: The electromagnetic compatibility protection circuit comprises the electromagnetic compatibility protection circuit described in any one of claims 1 to 8.

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