Piezoelectric ceramic tuned filter design method considering hysteresis effect compensation

Abstract

The invention discloses a method for designing a piezoelectric ceramic tuned filter considering hysteresis effect compensation, and the method comprises the steps: 1, setting specific constraint conditions, such as frequency range, insertion loss and the like, based on the actual frequency conversion EMI inhibition demands, therefore, the filter can effectively work in the frequency conversion noise suppression process; 2, response data of the piezoelectric ceramic filter are sampled in real time, the bias voltage is dynamically adjusted based on the hysteresis compensation factor, it is ensured that the filter can keep high frequency adjustment precision through the dynamic adjustment, and therefore frequency conversion noise is restrained, and a filtering result meeting the constraint condition is obtained. The piezoelectric ceramic tuned filter can effectively compensate frequency deviation caused by a piezoelectric ceramic hysteresis effect, and the adjustment precision and the noise suppression performance of the piezoelectric ceramic tuned filter are improved.

Description

Technical Field

[0001] This invention relates to the field of power electronic equipment, and in particular to a design method for a piezoelectric ceramic tuned filter that considers hysteresis compensation. Background Technology

[0002] With the widespread application of power electronic equipment, electromagnetic interference (EMI) has become one of the key issues affecting equipment performance and stability. Variable frequency EMI signals are usually caused by high-frequency switching operations, nonlinear component characteristics, and dynamic adjustments to control strategies, and these signals adversely affect the normal operation of the system.

[0003] Active EMI filters typically utilize the resonant characteristics of piezoelectric ceramics to suppress frequency conversion noise. However, piezoelectric ceramics exhibit hysteresis during bias voltage changes, causing a delay between the voltage and response of the piezoelectric ceramic, resulting in reduced frequency regulation accuracy. This hysteresis directly impacts filter performance, particularly in applications such as frequency conversion noise suppression and high-dynamic power electronic systems.

[0004] Existing technologies typically fail to adequately address the frequency shift issue caused by hysteresis, resulting in significant errors in the frequency adjustment process of active EMI filters, which affects their stability and noise suppression capabilities in high dynamic environments.

[0005] To address the aforementioned problems, this invention proposes an active EMI filter design method that considers piezoelectric ceramic hysteresis compensation. The aim is to improve the frequency regulation accuracy of the filter and optimize the frequency conversion EMI noise suppression effect by accurately compensating for the hysteresis effect, thereby enhancing the stability and reliability of high-dynamic power electronic systems. Summary of the Invention

[0006] Purpose of the invention: The technical problem to be solved by the present invention is to provide a design method for a piezoelectric ceramic tuned filter that considers hysteresis effect compensation, in order to address the shortcomings of the prior art.

[0007] To address the aforementioned technical problems, this invention discloses a design method for a piezoelectric ceramic tuned filter considering hysteresis compensation. The filtering steps of the piezoelectric ceramic tuned filter include:

[0008] Step 1: Based on the actual frequency conversion EMI (Electromagnetic Interference) suppression requirements, set specific constraints, such as frequency range and insertion loss, to ensure that the filter can work effectively in the frequency conversion noise suppression process;

[0009] Step 2: Sample the response data of the piezoelectric ceramic filter in real time, and dynamically adjust the bias voltage based on the hysteresis compensation factor. Through this dynamic adjustment, ensure that the filter can maintain a high frequency adjustment accuracy, thereby suppressing frequency conversion noise and obtaining a filtering result that meets the constraints.

[0010] This piezoelectric ceramic tuned filter can effectively compensate for the frequency shift caused by the hysteresis effect of piezoelectric ceramics, and improve the tuning accuracy and noise suppression performance of the piezoelectric ceramic tuned filter.

[0011] The calculation of the hysteresis compensation factor in step 2 specifically includes:

[0012] Step 2-1-1: Measure the voltage-response curves of the piezoelectric ceramic under different bias voltages to obtain the hysteresis loop;

[0013] Step 2-1-2: Based on the measured hysteresis loop, the hysteresis effect of piezoelectric ceramics is modeled using the (Prandtl-Ishlinskii) PI model;

[0014] Step 2-1-3: Based on the PI model, calculate the hysteresis compensation factor by fitting the hysteresis loop data.

[0015] The specific implementation of dynamically adjusting the bias voltage in step 2 includes the following steps:

[0016] Step 2-2-1: For the desired target resonant frequency, determine a theoretical bias voltage based on a preset ideal voltage-resonant frequency relationship;

[0017] Step 2-2-2: Take the theoretical bias voltage as input and substitute it into a pre-established piezoelectric ceramic hysteresis model to calculate the compensation voltage value used to counteract the hysteresis effect in real time.

[0018] Step 2-2-3: Superimpose the compensation voltage value with the theoretical bias voltage value to generate a correction bias voltage;

[0019] Step 2-2-4: Apply the correction bias voltage to the piezoelectric ceramic in real time to actively compensate for the frequency shift caused by the hysteresis effect and achieve precise adjustment of the resonant frequency.

[0020] The hysteresis model can dynamically predict the offset of the resonant frequency based on the voltage change history and the current input.

[0021] The PI model used in step 2-1-2 to model the hysteresis effect is as follows:

[0022] Set the hysteresis compensation factor to H. i (V i ):

[0023]

[0024] Among them, w ik The weighting coefficients are determined by experimentally measuring the hysteresis loop of the piezoelectric ceramic and calibrating the fitted model parameters. 'n' represents the number of operators, which determines the model accuracy. Play k (V i ) is the k-th basic hysteresis operator.

[0025] The k-th basic hysteresis operator Play k (V i ), that is, y(t) is specifically shown below:

[0026]

[0027] Among them, Play k [V i [(t)] represents the output of the k-th Play operator at time t, V i (t) represents the input voltage signal of the i-th piezoelectric ceramic, r k The threshold for the k-th Play operator can be set according to the following formula:

[0028]

[0029] Where K is the total number of operators, selected according to the precision required in actual use, and V max The maximum bias voltage applied to the piezoelectric ceramic is determined by the tuning range and the maximum safe electric field strength.

[0030] The constraints on the frequency conversion EMI suppression requirements mentioned in step 1 include parameters such as frequency range, insertion loss, and adjustment accuracy, to ensure that the filter does not affect the performance of other frequency bands during the frequency conversion noise suppression process.

[0031] The designed piezoelectric ceramic tuned filter was verified through an experimental platform. In the experiment, voltage fluctuation test was used to evaluate the performance of the piezoelectric ceramic tuned filter and to verify the effectiveness and stability of the hysteresis compensation strategy in practical applications.

[0032] The piezoelectric ceramic tuned filter comprises a piezoelectric ceramic sheet and electrodes.

[0033] The piezoelectric ceramic sheet may be one or more sheets.

[0034] Beneficial effects:

[0035] This invention employs the Prandtl-Ishlinskii (PI) model to accurately model the hysteresis effect of piezoelectric ceramics and calculates the hysteresis compensation factor, effectively compensating for the frequency shift caused by the hysteresis effect and improving the filter's accuracy and stability. Simultaneously, real-time sampling and dynamic adjustment compensation strategies ensure that the filter maintains high-precision frequency regulation under various operating conditions. Considering practical frequency conversion EMI suppression requirements, this invention sets constraints to ensure the filter can effectively suppress frequency conversion noise and optimize EMI suppression performance. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating a piezoelectric ceramic filter tuning method for designing a filter that considers hysteresis compensation, according to an embodiment of the present invention.

[0037] Figure 2 This is a schematic diagram of a segmented integrated piezoelectric ceramic tuned filter based on bias voltage according to an embodiment of the present invention. Detailed Implementation

[0038] A design method for a piezoelectric ceramic tuned filter considering hysteresis compensation, wherein the filtering steps of the piezoelectric ceramic tuned filter include:

[0039] Step 1: Based on the actual frequency conversion EMI (Electromagnetic Interference) suppression requirements, set specific constraints, such as frequency range and insertion loss, to ensure that the filter can work effectively in the frequency conversion noise suppression process;

[0040] Step 2: Sample the response data of the piezoelectric ceramic filter in real time, and dynamically adjust the bias voltage based on the hysteresis compensation factor. Through this dynamic adjustment, ensure that the filter can maintain a high frequency adjustment accuracy, thereby suppressing frequency conversion noise and obtaining a filtering result that meets the constraints.

[0041] This piezoelectric ceramic tuned filter can effectively compensate for the frequency shift caused by the hysteresis effect of piezoelectric ceramics, and improve the tuning accuracy and noise suppression performance of the piezoelectric ceramic tuned filter.

[0042] The calculation of the hysteresis compensation factor in step 2 specifically includes:

[0043] Step 2-1-1: Measure the voltage-response curves of the piezoelectric ceramic under different bias voltages to obtain the hysteresis loop;

[0044] Step 2-1-2: Based on the measured hysteresis loop, the hysteresis effect of piezoelectric ceramics is modeled using the (Prandtl-Ishlinskii) PI model;

[0045] Step 2-1-3: Based on the PI model, calculate the hysteresis compensation factor by fitting the hysteresis loop data.

[0046] The specific implementation of dynamically adjusting the bias voltage in step 2 includes the following steps:

[0047] Step 2-2-1: For the desired target resonant frequency, determine a theoretical bias voltage based on a preset ideal voltage-resonant frequency relationship;

[0048] Step 2-2-2: Take the theoretical bias voltage as input and substitute it into a pre-established piezoelectric ceramic hysteresis model to calculate the compensation voltage value used to counteract the hysteresis effect in real time.

[0049] Step 2-2-3: Superimpose the compensation voltage value with the theoretical bias voltage value to generate a correction bias voltage;

[0050] Step 2-2-4: Apply the correction bias voltage to the piezoelectric ceramic in real time to actively compensate for the frequency shift caused by the hysteresis effect and achieve precise adjustment of the resonant frequency.

[0051] The hysteresis model can dynamically predict the offset of the resonant frequency based on the voltage change history and the current input.

[0052] The PI model used in step 2-1-2 to model the hysteresis effect is as follows:

[0053] Set the hysteresis compensation factor to H. i (V i ):

[0054]

[0055] Among them, w ik The weighting coefficients are determined by experimentally measuring the hysteresis loop of the piezoelectric ceramic and calibrating the fitted model parameters. 'n' represents the number of operators, which determines the model accuracy. Play k (V i ) is the k-th basic hysteresis operator.

[0056] The k-th basic hysteresis operator Play k (V i ), that is, y(t) is specifically shown below:

[0057]

[0058] Among them, Play k [V i [(t)] represents the output of the k-th Play operator at time t, V i (t) represents the input voltage signal of the i-th piezoelectric ceramic, rk The threshold for the k-th Play operator can be set according to the following formula:

[0059]

[0060] Where K is the total number of operators, selected according to the precision required in actual use, and V max The maximum bias voltage applied to the piezoelectric ceramic is determined by the tuning range and the maximum safe electric field strength.

[0061] The constraints on the frequency conversion EMI suppression requirements mentioned in step 1 include parameters such as frequency range, insertion loss, and adjustment accuracy, to ensure that the filter does not affect the performance of other frequency bands during the frequency conversion noise suppression process.

[0062] The designed piezoelectric ceramic tuned filter was verified through an experimental platform. In the experiment, voltage fluctuation test was used to evaluate the performance of the piezoelectric ceramic tuned filter and to verify the effectiveness and stability of the hysteresis compensation strategy in practical applications.

[0063] The piezoelectric ceramic tuned filter comprises a piezoelectric ceramic sheet and electrodes.

[0064] The piezoelectric ceramic sheet may be one or more sheets.

[0065] In dynamic tuning filtering, the hysteresis effect of piezoelectric ceramics causes a significant deviation between the actual resonant frequency and the theoretically set frequency. This frequency deviation further deteriorates the filtering effect or even causes it to fail. Especially in frequency conversion noise suppression scenarios, dynamic frequency changes exacerbate the hysteresis effect, making it impossible for the filter to accurately track the target frequency, resulting in decreased suppression performance, or even complete loss of filtering capability in certain frequency bands. This invention effectively compensates for the frequency deviation caused by the hysteresis effect, improving the dynamic performance of piezoelectric ceramic tuned filters.

[0066] This invention provides a design method for a piezoelectric ceramic tuned filter considering hysteresis compensation. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A design method for a piezoelectric ceramic tuned filter considering hysteresis compensation, characterized in that, The filtering steps of the piezoelectric ceramic tuned filter include: Step 1: Based on the actual frequency converter EMI suppression requirements, set specific constraints; Step 2: Sample the response data of the piezoelectric ceramic filter in real time, and dynamically adjust the bias voltage based on the hysteresis compensation factor to suppress frequency conversion noise and obtain a filtering result that meets the constraints.

2. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 1, characterized in that, The calculation of the hysteresis compensation factor in step 2 specifically includes: Step 2-1-1: Measure the voltage-response curves of the piezoelectric ceramic under different bias voltages to obtain the hysteresis loop; Step 2-1-2: Based on the measured hysteresis loop, the PI model is used to model the hysteresis effect of piezoelectric ceramics; Step 2-1-3: Based on the PI model, calculate the hysteresis compensation factor by fitting the hysteresis loop data.

3. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 2, characterized in that, The specific implementation of dynamically adjusting the bias voltage in step 2 includes the following steps: Step 2-2-1: For the desired target resonant frequency, determine a theoretical bias voltage based on a preset ideal voltage-resonant frequency relationship; Step 2-2-2: Take the theoretical bias voltage as input and substitute it into a pre-established piezoelectric ceramic hysteresis model to calculate the compensation voltage value used to counteract the hysteresis effect in real time. Step 2-2-3: Superimpose the compensation voltage value with the theoretical bias voltage value to generate a correction bias voltage; Step 2-2-4: Apply the correction bias voltage to the piezoelectric ceramic in real time to actively compensate for the frequency shift caused by the hysteresis effect and achieve precise adjustment of the resonant frequency.

4. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 3, characterized in that, The hysteresis model can dynamically predict the offset of the resonant frequency based on the voltage change history and the current input.

5. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 2, characterized in that, The PI model used in step 2-1-2 to model the hysteresis effect is as follows: Set the hysteresis compensation factor to H. i (V i ): ； Among them, w ik The weighting coefficients are determined by experimentally measuring the hysteresis loop of the piezoelectric ceramic and calibrating the fitted model parameters. 'n' represents the number of operators, which determines the model accuracy. Play k (V i ) is the k-th basic hysteresis operator.

6. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 5, characterized in that, The k-th basic hysteresis operator Play k (V i ), that is, y(t) is specifically shown below: ； Among them, Play k [V i [(t)] represents the output of the k-th Play operator at time t, V i (t) represents the input voltage signal of the i-th piezoelectric ceramic, r k The threshold for the k-th Play operator can be set according to the following formula: ； Where K is the total number of operators, selected according to the precision required in actual use, and V max The maximum bias voltage applied to the piezoelectric ceramic is determined by the tuning range and the maximum safe electric field strength.

7. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 1, characterized in that, The constraints on the frequency conversion EMI suppression requirements mentioned in step 1 include frequency range, insertion loss, and adjustment accuracy.

8. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 1, characterized in that, The designed piezoelectric ceramic tuned filter was verified through an experimental platform. In the experiment, voltage fluctuation test was used to evaluate the performance of the piezoelectric ceramic tuned filter and to verify the effectiveness and stability of the hysteresis compensation strategy in practical applications.

9. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 1, characterized in that, The piezoelectric ceramic tuned filter comprises a piezoelectric ceramic sheet and electrodes.

10. The design method of a piezoelectric ceramic tuned filter considering hysteresis compensation according to claim 9, characterized in that, The piezoelectric ceramic sheet may be one or more sheets.

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