Power sensor communication interference suppression method and system based on piezoelectric ceramic filtering

Abstract

The invention discloses an electric power sensor communication interference suppression method and system based on piezoelectric ceramic filtering. The method comprises the following steps: measuring the communication interference noise frequency of an electric power sensor; establishing a relation model of the geometric dimension and the resonance frequency of the piezoelectric ring; calculating the geometric dimension of the piezoelectric circular ring required for suppressing the frequency; the obtained piezoelectric circular ring is connected to an EMI filter, and a Y capacitor in the EMI filter is replaced; a common mode choke matched with the piezoelectric circular ring is added into the EMI filter to design a piezoelectric EMI filter; and acquiring an external working state in real time, and dynamically controlling a piezoelectric circular ring in the piezoelectric EMI filter according to the interference frequency center real-time monitoring model to complete automatic tuning of the center frequency of the piezoelectric EMI filter. The power sensor communication interference noise suppression method has the capability of dynamically adapting to complex working environment changes while realizing efficient suppression of the communication interference noise of the power sensor, effectively reduces the size of the filter while ensuring the filtering performance, and reduces the suppression scheme cost.

Description

Technical Field

[0001] The present invention relates to the field of substation power sensor communication, and in particular to a power sensor communication interference suppression method and system based on piezoelectric ceramic filtering. Background Art

[0002] Substations, as the hub of the power grid, are responsible for the transmission and distribution of electrical energy and ensuring the safe and stable operation of the power system. Power sensors, the core of the substation's intelligent sensing system, monitor parameters such as voltage, current, and temperature in real time, enabling equipment status monitoring and risk warning. These sensors are fundamental to the safe operation of the power grid. With the development of smart grids and the power Internet of Things, the number and variety of sensors have increased significantly, placing even higher demands on communication stability. However, strong electromagnetic interference within substations (such as power-frequency electric and magnetic fields, and switching operations) can affect sensor reliability, leading to communication delays, data anomalies, false triggering, and even hardware damage. Especially in complex industrial sites, the distribution of interference spectrum is dynamic and unpredictable.

[0003] Therefore, studying communication interference in power sensors and its real-time solutions is of great significance to improving the security, reliability, and stability of smart grids. The resonant frequency of traditional filters is difficult to match the sensor communication interference frequency band, and the internal inductor components increase power consumption, volume, and cost, resulting in poor interference suppression and failure to meet the requirements for reliable sensor operation. Piezoelectric ceramics have very low impedance at the resonant frequency and exhibit capacitor-like characteristics at non-resonant frequencies. Therefore, they can replace capacitors in traditional filters and provide a lower impedance path for electromagnetic interference. However, most existing filters are "static designs," meaning that the resonant frequency is fixed during the manufacturing stage. They are unable to cope with the drift of external interference frequencies caused by changes in time, temperature, or load, resulting in attenuation of the filter's out-of-band performance. Summary of the Invention

[0004] In response to the above problems, the present invention provides a method and system for suppressing power sensor communication interference noise based on piezoelectric ceramic filtering, which can effectively suppress power sensor communication interference noise and dynamically adapt to changes in complex working environments.

[0005] The technical solution of the present invention is: a method for suppressing communication interference of a power sensor based on piezoelectric ceramic filtering, comprising:

[0006] Measure the communication interference noise frequency of the power sensor;

[0007] Piezoelectric ceramics were selected as the ring material, and a relationship model between the geometric dimensions and resonant frequency of the piezoelectric ring was established.

[0008] Obtaining the material parameters of the piezoelectric ring, and calculating the piezoelectric ring geometric dimensions required to suppress the frequency based on the established relationship model between the piezoelectric ring geometric dimensions and the resonant frequency, as well as the measured frequency of the communication interference noise;

[0009] Connect the piezoelectric ring of the appropriate size to the EMI filter to replace the Y capacitor in the EMI filter;

[0010] A piezoelectric EMI filter is designed by adding a common mode choke that matches the piezoelectric ring into the EMI filter;

[0011] The external working status is collected in real time, and a real-time monitoring model of the interference frequency center related to the external working status is established. According to the real-time monitoring model of the interference frequency center, the piezoelectric ring in the piezoelectric EMI filter is dynamically controlled to complete the automatic tuning of the center frequency of the designed piezoelectric EMI filter, thereby suppressing interference.

[0012] The spectrum analysis method is used to determine the main frequency of the interference noise, including:

[0013] First, perform Fourier transform on the collected noise signal;

[0014] Secondly, the power spectral density is calculated;

[0015] Finally, the main peak frequency is searched to obtain the center value of the communication interference noise frequency.

[0016] The relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency is as follows:

[0017]

[0018] Where, C0, C m , L m are the parameters in the electrical equivalent circuit of the piezoelectric ring, ε0 is the dielectric constant of vacuum, is the dielectric constant component under constant mechanical stress, k 31 is the electromechanical coupling coefficient, ρ is the volume density, is the elastic compliance constant, a is the outer diameter of the piezoelectric ring, b is the ring width of the piezoelectric ring, h is the thickness of the piezoelectric ring, and f is the main resonant frequency of the piezoelectric ring.

[0019] The main resonant frequency of the selected piezoelectric ring is the same as the center frequency of the power sensor communication interference noise.

[0020] The interference frequency center real-time monitoring model is as follows:

[0021]

[0022] Where, f EMI(t) is the center value of the frequency under real-time interference, f0 is the main interference frequency under reference temperature T0, α T is the temperature interference coefficient, α V is the voltage ripple interference coefficient, α I is the current interference coefficient, α ext is the electromagnetic interference coefficient, T(t) is the real-time temperature, ΔV(t) is the voltage ripple, is the current rising slope, E ext (t) is the external electromagnetic interference intensity.

[0023] The tuning mechanism satisfies the following equation:

[0024] |Δf=f EMI -f0|>ε

[0025] Where ε is a preset threshold. If it exceeds the preset threshold, the MEMS tunable element or digital capacitor array in the piezoelectric EMI filter matching network is adjusted so that the difference approaches 0 infinitely.

[0026] Tuning also needs to satisfy the following equation:

[0027]

[0028] Where f0(t) is the main resonant frequency of the piezoelectric EMI filter under real-time interference, C var (t) is the adjustable capacitor, and L is the inductance of the common-mode choke.

[0029] The power sensor communication interference suppression system based on piezoelectric ceramic filtering includes:

[0030] Noise module, used to measure the communication interference noise frequency of the power sensor;

[0031] A relationship module is used to select piezoelectric ceramics as the ring material and establish a relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency;

[0032] A calculation module is used to obtain the material parameters of the piezoelectric ring and calculate the geometric dimensions of the piezoelectric ring required to suppress the frequency based on the established relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency and the measured frequency of the communication interference noise;

[0033] Replacement module, used to connect a piezoelectric ring of the appropriate size to the EMI filter and replace the Y capacitor in the EMI filter;

[0034] A design module for designing a piezoelectric EMI filter by adding a common-mode choke that matches the piezoelectric ring;

[0035] The tuning module is used for collecting external working states in real time, establishing an interference frequency center real-time monitoring model related to the external working states, and dynamically controlling the piezoelectric EMI according to the interference frequency center real-time monitoring model

[0036] The piezoelectric ring in the filter completes automatic tuning of the designed piezoelectric EMI filter center frequency, thereby suppressing interference.

[0037] In the relationship module, the relationship model of the piezoelectric ring geometric size and the resonance frequency is as follows:

[0038]

[0039] In the formula, C0, C m , L m are parameters in the piezoelectric ring electrical equivalent circuit, ε0 is a vacuum dielectric constant, is a dielectric constant component under constant mechanical stress, k 31 is an electromechanical coupling coefficient, ρ is a volume density, is an elastic compliance constant, a is the outer diameter of the piezoelectric ring, b is the ring width of the piezoelectric ring, h is the thickness of the piezoelectric ring, and f is the main resonance frequency of the piezoelectric ring.

[0040] In the tuning module, the interference frequency center real-time monitoring model is as follows:

[0041]

[0042] In the formula, f EMI (t) is the center value of the frequency under real-time interference, f0 is the main interference frequency under the reference temperature T0, α T is a temperature interference coefficient, α V is a voltage ripple interference coefficient, α I is a current interference coefficient, α ext is an electromagnetic interference coefficient, T(t) is a real-time temperature, ΔV(t) is a voltage ripple, is a current rise slope, E ext (t) is an external electromagnetic interference intensity.

[0043] In the working process of the present application, the piezoelectric ring is used to replace the Y capacitor in the traditional EMI filter, based on the impedance resonance characteristics of the piezoelectric ring, the suppression effect of the piezoelectric ring on the specific noise frequency is better than that of the Y capacitor, the interference frequency center caused by environmental changes is compared with the main interference frequency, the real-time adjustment of the interference peak suppression is realized, the piezoelectric ring and the common mode choke coil are combined, the power sensor communication interference noise can be efficiently suppressed, and the ability of dynamically adapting to complex working environment changes can be realized, the filter volume is effectively reduced while the filtering performance is ensured, and the suppression scheme cost is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is a method flowchart of the present application;

[0045] Figure 2 is a schematic diagram of the piezoelectric ring geometry, polarization and vibration mode in the present application;

[0046] Figure 3 is an equivalent circuit of the piezoelectric ring in the present application;

[0047] Figure 4 is a schematic diagram of the piezoelectric EMI filter application designed by the piezoelectric ring combined with the common mode choke coil provided by the embodiment of the present application. DETAILED DESCRIPTION

[0048] The present application will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and cannot be used to limit the protection scope of the present application.

[0049] Referring to Figure 1 , the power sensor communication interference suppression method based on piezoelectric ceramic filtering provided by the embodiment of the present application performs the following steps S1-S6, completes the impedance resonance design of the piezoelectric ring, and can real-time tune the impedance resonance of the piezoelectric ring; at the same time, the environment perception and feedback control mechanism is introduced to realize adaptive matching and efficient suppression of the power sensor communication interference frequency, which specifically includes:

[0050] Step S1: measuring the communication interference noise frequency of the power sensor, using the frequency spectrum analysis method to determine the main frequency of the interference noise frequency as the target frequency for filter design and tuning;

[0051] In step S1, the frequency spectrum analysis method is used to determine the main frequency of the interference noise frequency, which includes:

[0052] Firstly, Fourier transform is performed on the collected noise signal, specifically:

[0053] V(f)=FFT|v(t)|

[0054] In the formula, V(f) represents the complex spectrum of the frequency domain signal, v(t) represents the real-time collected time domain interference signal, and FFT represents the algorithm for calculating the discrete Fourier transform;

[0055] Secondly, the power spectral density is calculated, specifically:

[0056] S(f)=|V(f)| 2

[0057] In the formula, S(f) represents the power spectral density, and |V(f)| 2 represents the square of the frequency domain amplitude, that is, the energy size of the frequency point.

[0058] Finally, the main peak frequency is searched, and the communication interference noise frequency center satisfies the following formula:

[0059] f EMI = argmax f S(f)

[0060] In the formula, f EMI represents the main interference frequency center value, argmax f S(f) represents the frequency point corresponding to the maximum power spectral density S(f) among all frequencies.

[0061] The spectrum analysis method has the following advantages: 1. It is suitable for complex multi-source interference scenes; 2. It is convenient for dynamic tracking and automatic processing; 3. It has strong energy intuitiveness, and the main frequency of interference is clear and visible; 4. It improves the frequency identification accuracy.

[0062] Step S2: Select piezoelectric ceramic as the ring material, and for the piezoelectric ring (i.e. ring-shaped piezoelectric ceramic), as shown in the reference figure Figure 2 , P is the polarization direction, and u r is the displacement direction. In the axial polarization vibration mode, according to the relationship satisfied by the equivalent circuit parameters of the piezoelectric ring and the material parameters of the piezoelectric ring at the resonance frequency, a relationship model of the geometric size of the piezoelectric ring and the resonance frequency is established, and the design of the resonance frequency of the piezoelectric ring is completed.

[0063] The relationship model of the geometric size of the piezoelectric ring and the resonance frequency is as follows:

[0064]

[0065] In the formula, C0, C m , and L m are parameters in the electrical equivalent circuit of the piezoelectric ring, ε0 is the vacuum dielectric constant, specifically 8.85x10 -12 F / m, is the dielectric constant component under constant mechanical stress, k 31 is the electromechanical coupling coefficient, ρ is the volume density, is the elastic compliance constant, a is the outer diameter of the piezoelectric ring, b is the ring width of the piezoelectric ring, h is the thickness of the piezoelectric ring, and f is the main resonance frequency of the piezoelectric ring.

[0066] The ring-shaped piezoelectric ceramic structure has good symmetry, clear resonance mode, strong controllability of resonance frequency, and is easy to replace the traditional Y capacitor structure, which improves the common mode interference selective suppression ability of the filter, reduces the loss and reduces the structure size.

[0067] Figure 3 C m , Lm 、R m The series resonant circuit composed of three dynamic elements and the parallel circuit composed of capacitor C0, where C m Indicates the spring stiffness, L m represents the inertial mass, R m Indicates mechanical loss.

[0068] Step S3: Based on the established relationship model between the geometric dimensions and resonant frequency of the piezoelectric ring, the target frequency of the measured sensor communication interference noise and the piezoelectric ceramic manufacturer's k 31 ,ρ, The size of the piezoelectric ring can be calculated based on the material parameters. The main resonant frequency of the selected piezoelectric ring needs to be the same as the center of the interference noise frequency.

[0069] Step S4: According to the geometric dimensions of the piezoelectric ring calculated in step S3, a piezoelectric ring of the required dimensions is manufactured, and the piezoelectric ring is connected to a traditional EMI filter to replace the Y capacitor in the filter;

[0070] Step S5: adding a common-mode choke coil matched with the piezoelectric ring to the EMI filter to design a piezoelectric EMI filter for suppressing communication interference noise of the power sensor;

[0071] Step S6: Construct an environmental perception module containing parameters such as temperature, current, and electromagnetic interference, collect the external working status in real time, establish a real-time monitoring model of the interference frequency center related to the external working status, and dynamically control the piezoelectric ring in the piezoelectric EMI filter based on the real-time monitoring model of the interference frequency center to complete the automatic tuning of the center frequency of the designed piezoelectric EMI filter, thereby suppressing interference.

[0072] In step S6, the interference frequency center real-time monitoring model is as follows:

[0073]

[0074] Where, f EMI (t) is the center value of the frequency under real-time interference, f0 is the main interference frequency under reference temperature T0, α T is the temperature interference coefficient, α V is the voltage ripple interference coefficient, α I is the current interference coefficient, α ext is the electromagnetic interference coefficient, T(t) is the real-time temperature, ΔV(t) is the voltage ripple, is the current rising slope, E ext (t) is the external electromagnetic interference intensity.

[0075] In step S6, based on the real-time monitoring of fEMI The difference from the center frequency of the current piezoelectric EMI filter is tuned to minimize the frequency offset. The tuning mechanism satisfies the following equation:

[0076] |Δf=f EMI -f0|>ε

[0077] Where ε is a preset threshold. If the threshold is exceeded, the MEMS tunable element or digital capacitor array in the piezoelectric EMI filter matching network is adjusted so that the difference approaches 0 infinitely. The tuning also needs to satisfy the following formula:

[0078]

[0079] Where C var (t) is the adjustable capacitor, L is the inductance of the common-mode choke, and f0(t) is the main resonant frequency of the piezoelectric EMI filter that changes under real-time interference.

[0080] The power sensor communication interference suppression system based on piezoelectric ceramic filtering includes:

[0081] Noise module, used to measure the communication interference noise frequency of the power sensor;

[0082] A relationship module is used to select piezoelectric ceramics as the ring material and establish a relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency;

[0083] A calculation module is used to obtain the material parameters of the piezoelectric ring and calculate the geometric dimensions of the piezoelectric ring required to suppress the frequency based on the established relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency and the measured frequency of the communication interference noise;

[0084] Replacement module, used to connect a piezoelectric ring of the appropriate size to the EMI filter and replace the Y capacitor in the EMI filter;

[0085] A design module for adding a common-mode choke that matches the piezoelectric ring to the EMI filter to design a piezoelectric EMI filter for suppressing power sensor communication interference noise;

[0086] The tuning module is used to collect the external working status in real time, establish a real-time monitoring model of the interference frequency center related to the external working status, and dynamically control the piezoelectric ring in the piezoelectric EMI filter based on the real-time monitoring model of the interference frequency center to complete the automatic tuning of the designed piezoelectric EMI filter center frequency, thereby suppressing interference.

[0087] In the relationship module, the relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency is as follows:

[0088]

[0089] Where, C0, C m , L m are the parameters in the electrical equivalent circuit of the piezoelectric ring, ε0 is the dielectric constant of vacuum, is the dielectric constant component under constant mechanical stress, k 31 is the electromechanical coupling coefficient, ρ is the volume density, is the elastic compliance constant, a is the outer diameter of the piezoelectric ring, b is the ring width of the piezoelectric ring, h is the thickness of the piezoelectric ring, and f is the main resonant frequency of the piezoelectric ring.

[0090] In the tuning module, the interference frequency center real-time monitoring model is as follows:

[0091]

[0092] Where, f EMI (t) is the center value of the frequency under real-time interference, f0 is the main interference frequency under reference temperature T0, α T is the temperature interference coefficient, α V is the voltage ripple interference coefficient, α I is the current interference coefficient, α ext is the electromagnetic interference coefficient, T(t) is the real-time temperature, ΔV(t) is the voltage ripple, is the current rising slope, E ext (t) is the external electromagnetic interference intensity.

[0093] The present invention has the following advantages:

[0094] 1) It has environmental self-adaptation capability and can dynamically adjust the resonant frequency of the piezoelectric ring according to the center drift of the interference frequency caused by external environmental changes (such as temperature, voltage ripple, current disturbance, etc.), always keeping it matched with the main interference frequency, and significantly improving the interference suppression stability of the filter in complex electromagnetic environments;

[0095] 2) Improve filter selectivity and depth. Compared with traditional fixed parameter filters, the piezoelectric resonant frequency can track the main interference frequency in real time, effectively suppressing high-amplitude, narrow-band communication interference. The filter has a higher attenuation capability and suppression depth for target interference;

[0096] 3) Enhance system robustness by using automatic tuning control to prevent detuning of the piezoelectric resonant structure due to environmental changes, reduce the risk of filter failure, and ensure the stability and reliability of the power sensor system in long-term operation;

[0097] 4) Retaining the miniaturization advantage of piezoelectric filters, the structure continues the miniaturization and high Q value characteristics of piezoelectric ring ceramics. The addition of tuning control circuits can be integrated into the sensor motherboard without significantly increasing the system size or power consumption. It is suitable for space- and power-sensitive edge power electronic equipment.

[0098] 5) Compatible with existing EMI filtering structures, the structure can directly replace the traditional Y capacitor filtering solution, and combined with the common mode choke to construct a piezoelectric EMI filter, which is easy to implement and promote industrially.

[0099] like Figure 4 As shown, the specific application environment of the present invention is a high-sensitivity signal acquisition scenario in the presence of strong electromagnetic interference (EMI) in the power system. The present invention is deployed between the substation power input terminal and sensitive equipment to construct a piezoelectric EMI filter with dynamic suppression capability. The input terminal is the substation power supply, which contains EMI sources such as high-frequency switching interference, common-mode noise, and voltage ripple; the piezoelectric EMI filter is the core of the present invention, and the common-mode choke provides preliminary common-mode suppression. The traditional Y capacitor is replaced by the piezoelectric ring, and the resonant frequency is designed to perform high-Q value notch suppression on the main interference frequency; the dynamic tuning mechanism combines the environmental perception module with the resonant frequency control circuit to adjust the equivalent parameters of the piezoelectric ring in real time, so that the resonant frequency of the piezoelectric ring remains the same as the external interference frequency.

[0100] The piezoelectric EMI filter designed in the present invention has precise frequency selection capability, while reducing volume and weight, and lowering power consumption, thus meeting the requirements of sensor miniaturization, low power consumption and high reliability.

[0101] By adopting innovative technologies of piezoelectric materials, real-time monitoring of environmental variables, and automatic adjustment of filter parameters, adaptive suppression of dynamic interference can be achieved, which can significantly improve the reliability of power sensors and thus support the stable operation of the power grid.

[0102] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in this field without departing from the spirit of the present invention.

Claims

1. A method for suppressing communication interference of power sensors based on piezoelectric ceramic filtering, characterized in that: include: Measure the communication interference noise frequency of the power sensor; Piezoelectric ceramics were selected as the ring material, and a relationship model between the geometric dimensions and resonant frequency of the piezoelectric ring was established. Obtaining the material parameters of the piezoelectric ring, and calculating the piezoelectric ring geometric dimensions required to suppress the frequency based on the established relationship model between the piezoelectric ring geometric dimensions and the resonant frequency, as well as the measured frequency of the communication interference noise; Connect the piezoelectric ring of the appropriate size to the EMI filter to replace the Y capacitor in the EMI filter; A piezoelectric EMI filter is designed by adding a common mode choke that matches the piezoelectric ring into the EMI filter; The external working status is collected in real time, and a real-time monitoring model of the interference frequency center related to the external working status is established. According to the real-time monitoring model of the interference frequency center, the piezoelectric ring in the piezoelectric EMI filter is dynamically controlled to complete the automatic tuning of the center frequency of the designed piezoelectric EMI filter, thereby suppressing interference.

2. The method for suppressing communication interference of a power sensor based on piezoelectric ceramic filtering according to claim 1, characterized in that: The spectrum analysis method is used to determine the main frequency of the interference noise, including: First, perform Fourier transform on the collected noise signal; Secondly, the power spectral density is calculated; Finally, the main peak frequency is searched to obtain the center value of the communication interference noise frequency.

3. The method for suppressing communication interference of a power sensor based on piezoelectric ceramic filtering according to claim 1, characterized in that: The relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency is as follows: Where, C0, C m , L m are the parameters in the electrical equivalent circuit of the piezoelectric ring, ε0 is the dielectric constant of vacuum, is the dielectric constant component under constant mechanical stress, k 31 is the electromechanical coupling coefficient, ρ is the volume density, is the elastic compliance constant, a is the outer diameter of the piezoelectric ring, b is the ring width of the piezoelectric ring, h is the thickness of the piezoelectric ring, and f is the main resonant frequency of the piezoelectric ring.

4. The method for suppressing communication interference of a power sensor based on piezoelectric ceramic filtering according to claim 1, characterized in that: The main resonant frequency of the selected piezoelectric ring is the same as the center frequency of the power sensor communication interference noise.

5. The method for suppressing communication interference of a power sensor based on piezoelectric ceramic filtering according to claim 1, characterized in that: The interference frequency center real-time monitoring model is as follows: Where, f EMI (t) is the center value of the frequency under real-time interference, f0 is the main interference frequency under reference temperature T0, α T is the temperature interference coefficient, α V is the voltage ripple interference coefficient, α I is the current interference coefficient, α ext is the electromagnetic interference coefficient, T(t) is the real-time temperature, ΔV(t) is the voltage ripple, is the current rising slope, E ext (t) is the external electromagnetic interference intensity.

6. The method for suppressing communication interference of a power sensor based on piezoelectric ceramic filtering according to claim 5, characterized in that: The tuning mechanism satisfies the following equation: |Δf=f EMI -f0|>e Where ε is the preset threshold. If it exceeds the preset threshold, the MEMS adjustable element or digital capacitor array in the piezoelectric EMI filter matching network is adjusted so that the difference approaches 0 infinitely.

7. The method for suppressing communication interference of a power sensor based on piezoelectric ceramic filtering according to claim 6, characterized in that: Tuning also needs to satisfy the following formula: Where f0(t) is the main resonant frequency of the piezoelectric EMI filter under real-time interference, C var (t) is the adjustable capacitor, and L is the inductance of the common-mode choke.

8. The power sensor communication interference suppression system based on piezoelectric ceramic filtering is characterized by: include: Noise module, used to measure the communication interference noise frequency of the power sensor; A relationship module is used to select piezoelectric ceramics as the ring material and establish a relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency; A calculation module is used to obtain the material parameters of the piezoelectric ring and calculate the geometric dimensions of the piezoelectric ring required to suppress the frequency based on the established relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency and the measured frequency of the communication interference noise; Replacement module, used to connect a piezoelectric ring of the appropriate size to the EMI filter and replace the Y capacitor in the EMI filter; A design module for designing a piezoelectric EMI filter by adding a common-mode choke that matches the piezoelectric ring; The tuning module is used to collect the external working status in real time, and dynamically control the piezoelectric ring in the piezoelectric EMI filter according to the real-time monitoring model of the interference frequency center, to complete the automatic tuning of the designed piezoelectric EMI filter center frequency, thereby suppressing interference.

9. The power sensor communication interference suppression system based on piezoelectric ceramic filtering according to claim 8, characterized in that: In the relationship module, the relationship model between the geometric dimensions of the piezoelectric ring and the resonant frequency is as follows: Where, C0, C m , L m are the parameters in the electrical equivalent circuit of the piezoelectric ring, ε0 is the dielectric constant of vacuum, is the dielectric constant component under constant mechanical stress, k 31 is the electromechanical coupling coefficient, ρ is the volume density, is the elastic compliance constant, a is the outer diameter of the piezoelectric ring, b is the ring width of the piezoelectric ring, h is the thickness of the piezoelectric ring, and f is the main resonant frequency of the piezoelectric ring.

10. The power sensor communication interference suppression system based on piezoelectric ceramic filtering according to claim 8, characterized in that: In the tuning module, the interference frequency center real-time monitoring model is as follows: Where, f EMI (t) is the center value of the frequency under real-time interference, f0 is the main interference frequency under reference temperature T0, α T is the temperature interference coefficient, α V is the voltage ripple interference coefficient, α I is the current interference coefficient, α ext is the electromagnetic interference coefficient, T(t) is the real-time temperature, ΔV(t) is the voltage ripple, is the current rising slope, E ext (t) is the external electromagnetic interference intensity.

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