On-line diagnosis device for working mode of surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics
By synchronously acquiring voltage-current waveforms and acoustic signals and extracting multi-dimensional feature parameters, the problem of real-time diagnosis of SDBD discharge modes in existing technologies has been solved, achieving efficient and reliable discharge mode identification and tracking, which is suitable for complex engineering environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INST OF ELECTRICAL ENG CHINESE ACAD OF SCI
- Filing Date
- 2026-02-02
- Publication Date
- 2026-05-08
AI Technical Summary
Existing technologies struggle to perform real-time and accurate single-cycle diagnosis of the discharge modes of surface dielectric barrier discharge actuators under harsh environments, especially for identifying filamentary, diffuse, and transitional modes. Furthermore, traditional methods are costly, have slow response times, and lack reliable discrimination.
By synchronously acquiring voltage-current waveforms and broadband acoustic response signals, multi-dimensional characteristic parameters such as time-domain waveform matching degree, frequency-domain energy coupling ratio, and instantaneous phase correlation are extracted from the two to establish a mapping relationship between the discharge microstructure and the electro-acoustic coupling fingerprint, thereby realizing non-optical real-time online diagnosis.
It achieves single-cycle real-time discrimination and dynamic tracking of SDBD discharge modes without the need for optical imaging, improving the engineering applicability, environmental robustness and physical interpretability of the diagnostic device, and supporting closed-loop control applications.
Smart Images
Figure CN121995172A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the interdisciplinary field of plasma technology and electrical equipment condition monitoring, specifically relating to an online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on the coupling characteristics of electroacoustic signals. Background Technology
[0002] Surface dielectric barrier discharge (SDBD) actuators are core actuators in cryogenic plasma flow control, widely used in areas such as spacecraft lift enhancement and boundary layer separation suppression. Their control effectiveness directly depends on the discharge operating mode, primarily including energy-concentrated filamentary discharges and uniformly distributed diffuse discharges. Therefore, accurate identification and real-time monitoring of discharge modes are prerequisites for achieving closed-loop plasma flow control.
[0003] Currently, the mainstream diagnostic method for SDBD discharge modes relies on enhancement-coupled devices (ICCDs) combined with nanosecond-level gated imaging technology. This method identifies modes by acquiring spatial images of discharge emission, and while it has high spatial resolution, it has significant limitations: ICCD devices are expensive and bulky, and require strictly dark environments, making them difficult to deploy in actual engineering sites such as wind tunnels and flight skins; its diagnosis usually relies on the accumulation of multiple periods of images, and it cannot capture microsecond-level mode transitions within a single period in real time, resulting in a response lag; in addition, this method is only sensitive to the luminescent region and is not sensitive to key physical processes such as dark discharge and surface charge dynamics, which may lead to misdiagnosis.
[0004] On the other hand, electro-acoustic joint diagnostic technology has been applied in the detection of partial discharge in power equipment. However, traditional methods are designed for discharges with low repetition frequency and high single-shot energy, where the electro-acoustic signals have a clear one-to-one correspondence, and the discharge type and acoustic signal characteristics differ significantly. SDBD, however, operates under high-frequency excitation in the kHz range, with extremely low single-shot discharge energy (microjoules), resulting in weak acoustic signals. Furthermore, at high repetition frequencies, the acoustic waves exhibit severe aliasing in the time domain, making traditional time-aligned electro-acoustic correlation methods difficult to apply directly. Existing analysis methods that rely solely on electrical parameters (such as current pulse characteristics) or the acoustic spectrum generally lack spatial resolution or have insufficient signal-to-noise ratio, making it difficult to achieve high-confidence real-time discrimination of SDBD filamentary, diffuse, and transition states.
[0005] Therefore, there is an urgent need to develop a non-optical technology that is suitable for harsh environments and can achieve real-time online diagnosis of SDBD discharge modes in a single cycle, in order to overcome the shortcomings of existing technologies, such as strong environmental dependence, slow response, and insufficient judgment reliability. Summary of the Invention
[0006] To address the aforementioned technical problems, this invention provides an online diagnostic device for the operating modes of a surface dielectric barrier discharge (SDBD) actuator based on electroacoustic signal coupling characteristics. By synchronously acquiring voltage-current waveforms and wideband acoustic response signals with high precision, it extracts multi-dimensional characteristic parameters such as time-domain waveform matching degree, frequency-domain energy coupling ratio, and instantaneous phase correlation. This establishes a mapping relationship between the discharge microstructure (e.g., the number of filamentary channels, spatial distribution density, and development continuity) and the electroacoustic coupling fingerprint. Thus, without the need for optical imaging, it achieves single-cycle-level real-time discrimination and dynamic tracking of SDBD filamentary, diffuse, and transitional operating modes, significantly improving the diagnostic device's engineering applicability, environmental robustness, and physical interpretability.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] An online diagnostic device for the operating mode of a surface dielectric barrier discharge actuator based on electroacoustic signal coupling characteristics, comprising:
[0009] Plasma exciter module, used to generate the discharge to be diagnosed;
[0010] An electrical parameter diagnostic module is used to synchronously acquire the voltage and current waveforms during the discharge process of the plasma actuator module;
[0011] An acoustic emission parameter diagnostic module is used to collect the acoustic signals excited by the discharge;
[0012] A synchronization and signal acquisition module is used to synchronously acquire the voltage waveform, current waveform, and acoustic signal.
[0013] The signal processing module is used to perform time-frequency analysis on the synchronously acquired current waveform and the acoustic signal, extract the coupling characteristics between them, and make real-time online determination of the working mode of the plasma exciter module based on the coupling characteristics; wherein, the synchronous timing reference and / or auxiliary feature extraction of the discharge is provided by the voltage waveform.
[0014] Furthermore, the acoustic emission parameter diagnostic module includes a high-sensitivity wideband microphone with a frequency response of 20 Hz to 100 kHz and a sensitivity of not less than 50 mV / Pa; the microphone is installed in a non-interference region 5 mm to 50 mm downstream of the plasma exciter.
[0015] Furthermore, the acoustic emission parameter diagnostic module includes a piezoelectric acoustic emission sensor with a center frequency of 50 kHz to 200 kHz. The sensor is attached to the undischarged area of the dielectric surface of the plasma exciter via a coupling agent.
[0016] Furthermore, it also includes an electromagnetic signal diagnostic module, used to collect the high-frequency electromagnetic radiation signal excited by the discharge and input it into the synchronization and signal acquisition module.
[0017] Furthermore, the synchronization and signal acquisition module is a multi-channel high-speed data acquisition device with an analog bandwidth of not less than 100 MHz, a sampling rate of not less than 250 MS / s, and supports external hardware triggering. The rising edge of the discharge current waveform is used as the trigger source, so that the synchronization acquisition time alignment accuracy of voltage, current and acoustic signals is better than 10 ns.
[0018] Furthermore, the signal processing module processes the synchronously acquired current signal and acoustic signal using Hilbert-Huang transform to generate their respective HHT spectra. By comparing the HHT spectra of the current signal and the acoustic signal, time-frequency coupling features used to distinguish discharge modes are extracted.
[0019] Furthermore, the signal processing module locates the starting time points of two surface ionization wave propagation events under a single pulse excitation by comparing the time-frequency characteristics of the current signal and the acoustic signal, and extracts the energy characteristics of the two events to achieve discharge mode differentiation.
[0020] Furthermore, the plasma exciter's operating modes include filamentary discharge, diffuse discharge, and transition state; the signal processing module analyzes the extracted coupling features and outputs the discrimination result of the operating mode.
[0021] Furthermore, the electrical parameter diagnostic module includes a high-voltage probe and a current probe. The high-voltage probe is connected in parallel to the high-voltage terminal of the plasma exciter, and the current probe is connected in series in the grounding circuit of the plasma exciter.
[0022] Furthermore, the signal processing module analyzes the signals of a single pulse discharge or a continuous pulse train discharge to perform single-cycle-level real-time discrimination and dynamic tracking of the working mode of the plasma exciter.
[0023] The beneficial effects of this invention are as follows:
[0024] It achieves non-optical real-time online diagnosis: it completely eliminates the dependence on expensive, bulky, and light-protected high-speed imaging equipment (such as ICCD). Diagnosis can be achieved by synchronously acquiring electrical and acoustic signals, which simplifies the device structure, significantly reduces costs, greatly enhances environmental adaptability, and can be directly deployed in complex engineering sites such as wind tunnel test sections and aircraft surfaces.
[0025] It possesses single-cycle-level real-time discrimination capability: through high-precision synchronous triggering and high-speed data acquisition, it can capture the complete electroacoustic signal dynamics within a single high-voltage pulse excitation cycle (on the order of microseconds). Combined with time-frequency analysis algorithms, it can achieve single-cycle-level real-time identification and dynamic tracking of discharge modes, with fast response speed, meeting the real-time requirements of flow control for state monitoring.
[0026] This method enhances the reliability and physical interpretability of pattern discrimination: by extracting multi-dimensional correlation features between electrical and acoustic signals in the time domain (matching degree), frequency domain (energy coupling), and instantaneous phase, a mapping relationship is established between the microscopic physical processes of discharge (such as filamentary channel development) and the measurable signal "fingerprint." Compared with single-parameter diagnosis, this discrimination method based on multi-physical quantity coupling features effectively overcomes signal aliasing and noise interference, significantly improves the ability to distinguish and increase the confidence level of filamentary, diffuse, and transitional modes, and provides a clear physical mechanism.
[0027] Support for closed-loop control applications: The real-time mode discrimination results output by this device provide a direct basis for the dynamic performance evaluation and feedback control of plasma actuators, laying a key technical foundation for building an efficient and adaptive plasma flow control closed-loop system. Attached Figure Description
[0028] Figure 1 This is a structural diagram of an online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on the coupling characteristics of electroacoustic signals, according to the present invention.
[0029] Figure 2 This is a graph showing the time-domain processing results of a single discharge electroacoustic signal.
[0030] Figure 3 The time-frequency domain differentiation results for single-pulse discharge modes;
[0031] Figure 4 The result diagram distinguishes the discharge modes of different pulse train discharges.
[0032] Figure label:
[0033] Plasma exciter module 1, high voltage probe 21, current probe 22, acoustic emission parameter diagnosis module 3, electromagnetic signal diagnosis module 4, synchronization and signal acquisition module 5, nanosecond pulse high voltage power supply 6. Detailed Implementation
[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0035] refer to Figure 1 The schematic diagram shown illustrates that the online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics provided in this embodiment mainly consists of the following six parts:
[0036] Plasma Actuator Module 1: This module is the SDBD actuator itself to be diagnosed, and it is the physical source that generates discharges and excites various signals. Its typical structure includes a dielectric substrate, a high-voltage electrode, and a ground electrode, which are laid on the surface where flow control is required.
[0037] Electrical Parameter Diagnostic Module: This module is used to capture the electrical characteristics of the discharge process with high precision. Specifically, it includes a high-voltage probe 21 and a current probe 22. The high-voltage probe 21 is connected in parallel to the high-voltage terminal of the plasma exciter module 1 to acquire the applied voltage waveform u(t); the current probe 22 is connected in series in the grounding circuit of the plasma exciter module 1 to acquire the current waveform i(t) flowing through the exciter. Together, they aim to fully capture the current pulse details and voltage overshoot characteristics of the nanosecond pulse high-voltage power supply 6 applied across the plasma exciter module 1.
[0038] Acoustic emission parameter diagnostic module 3: This module is used to acquire acoustic signals excited by discharge. Its core sensor can be a high-sensitivity wideband microphone (frequency response 20 Hz–100 kHz, sensitivity ≥50 mV / Pa) or a piezoelectric acoustic emission sensor (center frequency 50–200 kHz). The microphone is typically installed non-contactly in a non-interference area a certain distance (e.g., 5–50 mm) downstream of the plasma exciter module 1 to acquire the sound pressure signal p(t); the acoustic emission sensor can be attached to the undischarged area of the dielectric surface using a coupling agent to acquire the acoustic vibration signal x(t).
[0039] Electromagnetic signal diagnostic module 4 (optional): This module uses an ultra-high frequency antenna and is placed in the near field region of the plasma exciter module 1 to monitor the high-frequency electromagnetic radiation signal e(t) generated during the discharge process as an auxiliary discrimination feature.
[0040] Synchronization and Signal Acquisition Module 5: This module is the core for achieving strict time alignment of multiple signals. It employs a multi-channel high-speed data acquisition device (such as a digital storage oscilloscope or a high-speed data acquisition card). It has at least four channels, an analog bandwidth of at least 100 MHz, a sampling rate of at least 250 MS / s, and supports external hardware triggering. During operation, the rising edge of the current-driven signal or other reliable signals is used as a unified trigger source to ensure the synchronous acquisition of voltage, current, sound pressure, and optional electromagnetic signals (i.e., simultaneously connecting the electrical parameter diagnostic module, acoustic emission parameter diagnostic module 3, and electromagnetic signal diagnostic module 4). The time alignment accuracy is better than 10 ns to meet the complete capture requirements of the microsecond-level dynamic process within a single discharge cycle.
[0041] Signal Processing Module: This module receives the synchronously acquired raw signals and executes the core analysis algorithm. It uses algorithms with time-frequency analysis capabilities, such as the Hilbert-Huang Transform (HHT), to process the signals and generate the HHT spectrum. By comparing the time-frequency characteristics of signals such as current, acoustic emission, and electromagnetic waves, the module locates the start and end times of two surface ionization wave (SIW) propagation events and extracts energy characteristics, ultimately achieving the differentiation and discrimination of discharge modes.
[0042] The above six modules are connected in sequence through electrical connections and data streams, forming a complete technical chain from signal perception and synchronous acquisition to feature analysis and pattern output.
[0043] Example
[0044] This example demonstrates a typical in-laboratory diagnostic configuration:
[0045] Plasma exciter: The dielectric layer is an epoxy resin board with a thickness of 1 mm; the high voltage electrode is a copper foil strip with a width of 3 mm; the grounding electrode is an aluminum foil with a width of 5 mm, and the electrode spacing is 20 mm.
[0046] Electrical parameter diagnostic module: A Tektronix P6015A high-voltage probe (75 MHz bandwidth) is connected in parallel to the high-voltage end; a Pearson 2877 current probe (200 MHz bandwidth) is connected in series to the grounding circuit.
[0047] Acoustic emission parameter diagnostic module: A GRAS 46AE 1 / 2-inch condenser microphone (frequency response 20 Hz – 100 kHz, sensitivity 50 mV / Pa) is installed 20 mm downstream of the exciter, with the microphone spindle perpendicular to the discharge surface.
[0048] Synchronization and signal acquisition module: A Tektronix MDO3104 four-channel mixed-domain oscilloscope (analog bandwidth 100 MHz, maximum sampling rate 2.5 GS / s) is used. In this embodiment, the sampling rate is set to 250 MS / s. The synchronization output (TTL level) of the high-voltage pulse source is connected to the external trigger input port of the oscilloscope.
[0049] Signal processing module: This is implemented by a computer running analysis software. The software communicates with the oscilloscope via a LAN interface to acquire data.
[0050] Diagnostic process and procedures:
[0051] Step 1: System Connection and Parameter Settings. (Click...) Figure 1The connections between the sensors and the acquisition device are shown. In the software, set the oscilloscope trigger mode to "external edge trigger" and the trigger level to 1.5 V to capture each high-voltage pulse cycle.
[0052] Step 2: Synchronous Signal Acquisition. The exciter is driven by a nanosecond pulse power supply, with the following driving parameters set: frequency 5kHz, peak-to-peak voltage 15 kV, and pulse width 200 ns. After power-on, the oscilloscope triggers in each pulse cycle, synchronously acquiring and storing waveform data from three channels: voltage u(t), current i(t), and sound pressure p(t). The measured time alignment error is less than 5 ns.
[0053] Step 3: Signal Processing and Feature Extraction. The analysis software reads a set of synchronized data. First, the original signal is digitally bandpass filtered (current signal: 1 kHz – 20 MHz; sound pressure signal: 1 kHz – 80 kHz) to suppress noise. Then, the filtered current signal i(t) and sound pressure signal p(t) are subjected to Hilbert-Huang Transform (HHT) to obtain their Hilbert spectra Hi(t,f) and Hp(t,f), respectively.
[0054] Step 4: Pattern identification. For example... Figure 2 As shown, by analyzing Hi(t,f), the precise times t1 and t2 of the two SIW propagation events (corresponding to the two main pulses on the current waveform) under a single pulse excitation can be clearly identified. Next, the spectral energy distributions of Hi(t,f) and Hp(t,f) within the time windows of t1 and t2 are compared.
[0055] For the filamentary discharge mode, the current spectrum exhibits significant high-frequency (>100 kHz) spikes at t1 and t2, while the corresponding high-frequency energy proportion of the acoustic spectrum is relatively low, and the acoustic energy ratio of the two events follows a specific pattern.
[0056] For diffuse discharge mode, the current spectrum energy distribution is relatively wide and the amplitude is relatively low, mainly concentrated in the mid-to-low frequency range (<50kHz), while the corresponding acoustic spectrum energy is relatively high and more uniformly distributed.
[0057] The built-in classifier in the software (in this embodiment, a simple discriminator based on feature thresholds) automatically outputs the discharge mode discrimination result of the current pulse based on these extracted coupling features (such as specific frequency band energy ratio, time-frequency correlation, etc.).
[0058] Step 5: Result Display and Output. Diagnostic results can be displayed in real-time on the software interface (e.g., ...). Figure 3 , Figure 4 The diagram shows the discrimination results under different conditions, and the results can be stored or forwarded to the control system to provide a basis for the closed-loop control of the exciter.
[0059] This embodiment verifies that the device and method of the present invention can effectively and in real time distinguish different discharge operating modes of the SDBD exciter without relying on optical equipment.
[0060] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. An online diagnostic device for the operating mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics, characterized in that, include: Plasma exciter module, used to generate the discharge to be diagnosed; An electrical parameter diagnostic module is used to synchronously acquire the voltage and current waveforms during the discharge process of the plasma actuator module; An acoustic emission parameter diagnostic module is used to collect the acoustic signals excited by the discharge; A synchronization and signal acquisition module is used to synchronously acquire the voltage waveform, current waveform, and acoustic signal; The signal processing module is used to perform time-frequency analysis on the synchronously acquired current waveform and the acoustic signal, extract the coupling characteristics between them, and make real-time online determination of the working mode of the plasma exciter module based on the coupling characteristics; wherein, the synchronous timing reference and / or auxiliary feature extraction of the discharge is provided by the voltage waveform.
2. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, The acoustic emission parameter diagnostic module includes a high-sensitivity wideband microphone with a frequency response of 20 Hz to 100 kHz and a sensitivity of not less than 50 mV / Pa; the microphone is installed in a non-interference region 5 mm to 50 mm downstream of the plasma exciter.
3. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, The acoustic emission parameter diagnostic module includes a piezoelectric acoustic emission sensor with a center frequency of 50 kHz to 200 kHz. The sensor is attached to the undischarged area of the dielectric surface of the plasma exciter via a coupling agent.
4. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, It also includes an electromagnetic signal diagnostic module, which is used to collect the high-frequency electromagnetic radiation signal excited by the discharge and input it into the synchronization and signal acquisition module.
5. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, The synchronization and signal acquisition module is a multi-channel high-speed data acquisition device with an analog bandwidth of not less than 100 MHz, a sampling rate of not less than 250 MS / s, and supports external hardware triggering. The rising edge of the discharge current waveform is used as the trigger source, so that the synchronization acquisition time alignment accuracy of voltage, current and acoustic signals is better than 10 ns.
6. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, The signal processing module processes the synchronously acquired current and acoustic signals using Hilbert-Huang transform to generate their respective HHT spectra. By comparing the HHT spectra of the current and acoustic signals, time-frequency coupling features used to distinguish discharge modes are extracted.
7. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, The signal processing module locates the starting time of two surface ionization wave propagation events under a single pulse excitation by comparing the time-frequency characteristics of the current signal and the acoustic signal, and extracts the energy characteristics of the two events to distinguish the discharge modes.
8. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, The plasma exciter operates in three modes: filamentary discharge, diffuse discharge, and transition state. The signal processing module analyzes the extracted coupling features and outputs the discrimination result of the operating mode.
9. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, The electrical parameter diagnostic module includes a high-voltage probe and a current probe. The high-voltage probe is connected in parallel to the high-voltage terminal of the plasma exciter, and the current probe is connected in series in the grounding circuit of the plasma exciter.
10. The online diagnostic device for the working mode of a surface dielectric barrier discharge exciter based on electroacoustic signal coupling characteristics according to claim 1, characterized in that, The signal processing module analyzes the signals of single pulse discharge or continuous pulse train discharge to perform single-cycle-level real-time discrimination and dynamic tracking of the working mode of the plasma exciter.