Self-adaptive power supply adjusting method and system of acoustic thermal imager

Abstract

The invention discloses a self-adaptive power supply adjusting method and system for an acoustic thermal imager, and the method comprises the steps: measuring the surface temperature and output voltage of a lithium battery, controlling the lithium battery to stop outputting when the surface temperature exceeds a set protection temperature, and estimating the current electric quantity through employing the output voltage based on a charge state estimation model; measuring acoustic imaging power consumption of acoustic imaging in real time, judging whether an acoustic imaging module is in an active working state or not according to the acoustic imaging power consumption, and turning off a power supply of an acoustic imaging device if the acoustic imaging module is in an inactive working state according to the current electric quantity and the acoustic imaging power consumption; thermal imaging power consumption of thermal imaging is measured in real time, whether a thermal imaging module is in an active working state or not is judged according to the thermal imaging power consumption, and if the thermal imaging module is in an inactive working state according to the current electric quantity and the thermal imaging power consumption, a power source of the thermal imaging device is turned off.

Description

Technical Field

[0001] The present invention relates to the technical field of battery management, and particularly to an adaptive power supply regulation method and system for an acoustic thermal imager. Background Art

[0002] Acoustic imaging is a sound source localization technology that uses a microphone array to synchronously collect multi-channel sound signals and uses algorithms such as beamforming to calculate the distribution of sound magnitude on a spatial plane, thereby visually identifying the position with the largest sound in the plane, that is, the sound source position. Thermal imaging is a non-contact temperature measurement technology that uses a sensor array sensitive to temperature to obtain the temperature of each grid point on a plane. Acoustic imaging and thermal imaging are both used in the partial discharge detection of power facilities. The two technologies have a complementary effect. A portable detection device uses both acoustic imaging and thermal imaging technologies for data fusion display, which can more quickly locate partial discharge and is beneficial to improving the efficiency of inspection work.

[0003] However, the structure of a detection device with both acoustic imaging and thermal imaging technologies is more complex and the power consumption is higher. In the case of battery power supply, the usage time of the device is shortened, affecting the user experience. Summary of the Invention

[0004] The object of the present invention is to provide an adaptive power supply regulation method for an acoustic thermal imager.

[0005] To achieve the above object, the present invention is implemented according to the following technical solutions:

[0006] The present invention includes the following steps:

[0007] Measure the surface temperature and output voltage of the lithium battery. When the surface temperature exceeds the set protection temperature, control the lithium battery to stop output, and estimate the current power based on the state of charge estimation model using the output voltage;

[0008] Measure the acoustic imaging power consumption of the acoustic imaging in real time, judge whether the acoustic imaging module is in an active working state according to the acoustic imaging power consumption, and according to the current power combined with the acoustic imaging power consumption, if it is in a non-active working state, turn off the power of the acoustic imaging device;

[0009] Measure the thermal imaging power consumption of the thermal imaging in real time, judge whether the thermal imaging module is in an active working state according to the thermal imaging power consumption, and according to the current power combined with the thermal imaging power consumption, if it is in a non-active working state, turn off the power of the thermal imaging device; if the current power is low, the power main control module of the lithium battery turns off the device in the non-active working state..

[0010] Further, the method for estimating the current power using the output voltage based on the state of charge estimation model includes:

[0011] Establish a mapping table of the output voltage and charge state of a lithium battery at different temperatures through experiments, and perform compensation in combination with the real-time surface temperature. The expression is:

[0012]

[0013] Where the output voltage of the lithium battery is U out , the surface temperature of the lithium battery is T, the state of charge of the lithium battery is SOC, and the experimental calibration coefficients are β, μ, and α respectively;

[0014] When the load fluctuates, introduce the current integration method to correct the error of voltage hysteresis. The expression is:

[0015]

[0016] Where the corrected state of charge of the lithium battery is The initial time is t o , the nominal capacity of the lithium battery is D nom , the current of the lithium battery at time t is i(t), and the state of charge of the lithium battery calculated based on the open-circuit voltage is SOC OCV ;

[0017] Divide the surface temperature into multiple intervals, use different mapping tables of output voltage and charge state in each interval, record the capacity decay curve caused by lithium battery aging, dynamically adjust the parameters of the state of charge estimation model, and output the adjusted state of charge and the mapping table of charge state as the current battery level.

[0018] Furthermore, a method for judging whether the acoustic imaging module is in an active working state according to the acoustic imaging power consumption includes:

[0019] Adopt ultra-high frequency to capture transient power fluctuations based on the acoustic imaging power consumption, and use Butterworth filters and wavelet denoising to separate high-frequency noise and effective signals;

[0020] Adopt short-time Fourier transform to divide time windows, analyze the spectral energy distribution, capture the power characteristics of the periodic working mode, and use Hamming weight difference to calculate the power consumption difference caused by the input change of the characteristic module;

[0021] Resample and align the non-uniformly adopted power data set, establish a probability model according to historical data, dynamically update the power variance threshold of the active state, and use the trapezoidal formula integration method to detect the instantaneous perturbation of the second derivative mutation;

[0022] If the power consumption difference shows specific fluctuations, the acoustic imaging module is in an active state; if the power consumption difference remains stable for a long time or the power is close to the baseline noise, the acoustic imaging module is in an inactive state.

[0023] Further, a method for judging whether the thermal imaging module is in an active working state according to the thermal imaging power consumption includes:

[0024] Collect the working temperature of the thermal imaging module, select a short-time window to capture instantaneous mutations, and calculate the mean square rate and the maximum deviation rate:

[0025]

[0026] μ(U) = μ o ·(1 + ζ(U - U ref ))

[0027]

[0028] where the standard deviation of the thermal imaging power consumption is σ, the variance of the thermal imaging power consumption is σ 2 , the mean value of the thermal imaging power consumption is μ, the mean square rate is the maximum deviation rate is the maximum thermal imaging power consumption within the time window is H max , the minimum thermal imaging power consumption within the time window is H min , the working temperature of the thermal imaging module is U, the reference temperature is U ref , the temperature compensation coefficient is ζ, the average power consumption at room temperature is μ o , the standard deviation of the sensor noise is σ noise ;

[0029] When the mean square rate is greater than 1.2 and the maximum deviation rate is greater than 0.6, the thermal imaging module is in an active state; in a high-temperature environment, the mean value μ is corrected according to the temperature sensor data. If the environmental temperature is greater than 40 degrees, the thresholds of the mean square rate and the maximum deviation rate are adjusted, and the mean square rate is greater than 0.9 and the maximum deviation rate is greater than 0.4.

[0030] In a second aspect, an adaptive power supply regulation system for an acoustic thermal imager includes a lithium battery, a voltage acquisition module, a temperature measurement module, an acoustic imaging power consumption measurement module, a thermal imaging power consumption measurement module, an acoustic imaging power supply switch module, a thermal imaging power supply switch module, and a power supply main control module;

[0031] The temperature measurement module measures the surface temperature of the lithium battery; the voltage measurement module measures the output voltage of the battery;

[0032] The power supply main control module obtains the surface temperature of the lithium battery through the temperature measurement module. When the temperature exceeds the set protection temperature, it controls the lithium battery to stop output; the power supply main control module obtains the output voltage of the lithium battery through the voltage measurement module and estimates the current power according to the voltage;

[0033] Measure the power consumption of the acoustic imaging in real time, determine whether the acoustic imaging module is in an active working state according to the acoustic imaging power consumption, and combine the current battery level with the acoustic imaging power consumption. If it is in an inactive working state, turn off the power supply of the acoustic imaging device;

[0034] Measure the power consumption of the thermal imaging in real time, determine whether the thermal imaging module is in an active working state according to the thermal imaging power consumption, and combine the current battery level with the thermal imaging power consumption. If it is in an inactive working state, turn off the power supply of the thermal imaging device.

[0035] The beneficial effects of the present invention are:

[0036] The present invention is an adaptive power supply adjustment method and system for an acoustic-thermal imager. Compared with the prior art, the present invention has the following technical effects:

[0037] This application can obtain the working state relationship between multiple battery management modules connected in parallel and the power supply main control module. On the one hand, by detecting the battery temperature, the power supply main control module can be protected in real time to prevent continuous power supply at too high a temperature, thereby damaging the power supply main control module; on the other hand, according to the power consumption of the acoustic imaging device and the thermal imaging device, it can be judged whether each is in an idle state based on the actual power of the acoustic imaging and thermal imaging, so as to automatically turn off or turn on the acoustic imaging device or the thermal imaging device, reduce the device power consumption, extend the battery life, and the power supply main control module manages the power consumption of each device, reducing the complexity of upper-layer software development and improving the reliability of the overall device. Description of the Drawings

[0038] Figure 1 It is a flowchart of the steps of the adaptive power supply adjustment method for the acoustic-thermal imager of the present invention;

[0039] Figure 2 It is a connection schematic diagram of the power management system provided by the embodiment of the present application. Detailed Embodiments

[0040] The present invention will be further described below through specific embodiments. The illustrative embodiments and descriptions herein are used to explain the present invention, but not to limit the present invention.

[0041] The adaptive power supply adjustment method and system for the acoustic-thermal imager of the present invention include the following steps:

[0042] As Figure 1 shown, in this embodiment, it includes the following steps:

[0043] Measure the surface temperature and output voltage of the lithium battery. When the surface temperature exceeds the set protection temperature, control the lithium battery to stop output, and estimate the current battery level using the output voltage based on the state of charge estimation model;

[0044] In the actual evaluation, a certain lithium battery was used as the research object. The data of the lithium battery were: surface temperature 55°C, output voltage 3.7V, current at the observation moment 0.3A, and nominal capacity 2000 mA;

[0045] The data of the acoustic imaging module were: the acoustic imaging power in measurement period 1 fluctuated by 1.2W, the acoustic imaging power in measurement period 2 fluctuated by 1W, and the acoustic imaging power in measurement period 3 fluctuated by 1.3W;

[0046] The data of the thermal imaging module were: operating temperature 48°C, thermal imaging power consumption in measurement period 1 was 2.8W, thermal imaging power consumption in measurement period 2 was 1.2, thermal imaging power consumption in measurement period 3 was 3.5W, thermal imaging power consumption in measurement period 4 was 0.9W, maximum thermal imaging power consumption was 1.2W, minimum thermal imaging power consumption was 1W, power consumption standard deviation was 0.1W, power consumption mean was 1.1W, and ambient temperature was 45°C;

[0047] The current battery level was 71.1%;

[0048] Measure the acoustic imaging power consumption of the acoustic imaging in real time, judge whether the acoustic imaging module is in the active working state according to the acoustic imaging power consumption, and according to the current battery level combined with the acoustic imaging power consumption, if it is in the non-active working state, then turn off the power of the acoustic imaging device;

[0049] Measure the thermal imaging power consumption of the thermal imaging in real time, judge whether the thermal imaging module is in the active working state according to the thermal imaging power consumption, and according to the current battery level combined with the thermal imaging power consumption, if it is in the non-active working state, then turn off the power of the thermal imaging device; if the current battery level is low, the power main control module of the lithium battery turns off the devices in the non-active working state;

[0050] In the actual evaluation, the power variance of the acoustic imaging module was 0.0156, the power consumption difference was 0.26, the power variance threshold was 0.152, and the acoustic imaging module was in the non-active state;

[0051] Thermal imaging module: the sensor noise standard was 0.15W, the temperature compensation coefficient was 0.02, the mean square rate was 1.084, the maximum deviation rate was 1.24W, and the thermal imaging module was in the active state;

[0052] When the current battery level is lower than 13%, turn off the devices in the non-active working state.

[0053] In this embodiment, the method for estimating the current battery level based on the state of charge estimation model using the output voltage includes:

[0054] An output voltage - state of charge mapping table of the lithium - battery at different temperatures is established through experiments, and compensation is carried out in combination with the real - time surface temperature. The expression is:

[0055]

[0056] Where the output voltage of the lithium - battery is U out , the surface temperature of the lithium - battery is T, the state of charge of the lithium - battery is SOC, and the experimentally calibrated coefficients are β, μ, α respectively;

[0057] When the load fluctuates, the current integration method is introduced to correct the error of voltage hysteresis. The expression is:

[0058]

[0059] Where the corrected state of charge of the lithium - battery is The initial time is t o , the nominal capacity of the lithium - battery is D nom , the current of the lithium - battery at time t is i(t), and the state of charge of the lithium - battery calculated based on the open - circuit voltage is SOC OCV ;

[0060] The surface temperature is divided into multiple intervals. Different output voltage - state of charge mapping tables are used in each interval. The capacity decay curve caused by the aging of the lithium - battery is recorded, the parameters of the state - of - charge estimation model are dynamically adjusted, and the adjusted state of charge and the state - of - charge mapping table are output as the current battery level.

[0061] In this embodiment, the method for judging whether the acoustic imaging module is in an active working state according to the acoustic imaging power consumption includes:

[0062] Based on the acoustic imaging power consumption, ultra - high - frequency is used to capture transient power fluctuations, and Butterworth filters and wavelet denoising are used to separate high - frequency noise and effective signals;

[0063] The short - time Fourier transform is used to divide time windows, analyze the spectral energy distribution, capture the power characteristics of the periodic working mode, and the Hamming - weighted difference is used to calculate the power consumption difference caused by the input change of the characteristic module;

[0064] The non - uniformly sampled power data set is resampled and aligned, a probability model is established according to historical data, the power variance threshold of the active state is dynamically updated, and the trapezoidal formula integration method is used to detect the instantaneous perturbation of the second - derivative mutation;

[0065] If the power consumption difference shows a specific fluctuating change, the acoustic imaging module is in an active state; if the power consumption difference remains stable for a long time or the power is close to the baseline noise, the acoustic imaging module is in an inactive state.

[0066] In this embodiment, the method for determining whether the thermal imaging module is in an active working state according to the thermal imaging power consumption includes:

[0067] Collect the working temperature of the thermal imaging module, select a short-time window to capture instantaneous mutations, and calculate the mean square rate and the maximum deviation rate:

[0068]

[0069] μ(U) = μ o ·(1 + ζ(U - U ref ))

[0070]

[0071] where the standard deviation of the thermal imaging power consumption is σ, the variance of the thermal imaging power consumption is σ 2 , the mean value of the thermal imaging power consumption is μ, the mean square rate is the maximum deviation rate is the maximum thermal imaging power consumption within the time window is H max , the minimum thermal imaging power consumption within the time window is H min , the working temperature of the thermal imaging module is U, the reference temperature is U ref , the temperature compensation coefficient is ζ, the mean power consumption at room temperature is μ o , the standard deviation of the sensor noise is σ noise ;

[0072] When the mean square rate is greater than 1.2 and the maximum deviation rate is greater than 0.6, the thermal imaging module is in an active state; in a high-temperature environment, the mean value μ is corrected according to the temperature sensor data. If the environmental temperature is greater than 40 degrees, the thresholds of the mean square rate and the maximum deviation rate are adjusted, and the mean square rate is greater than 0.9 and the maximum deviation rate is greater than 0.4.

[0073] In a second aspect, an adaptive power supply regulation system for an acoustic thermal imager includes a lithium battery, a voltage acquisition module, a temperature measurement module, an acoustic imaging power consumption measurement module, a thermal imaging power consumption measurement module, an acoustic imaging power supply switch module, a thermal imaging power supply switch module, and a power supply main control module;

[0074] The temperature measurement module measures the surface temperature of the lithium battery; the voltage measurement module measures the output voltage of the battery;

[0075] The power supply main control module obtains the surface temperature of the lithium battery through the temperature measurement module, and controls the lithium battery to stop output when the temperature exceeds the set protection temperature; the power supply main control module obtains the output voltage of the lithium battery through the voltage measurement module and estimates the current power according to the voltage;

[0076] Measure the power consumption of the acoustic imaging in real time, determine whether the acoustic imaging module is in an active working state according to the acoustic imaging power consumption, and combine the current battery level with the acoustic imaging power consumption. If it is in an inactive working state, turn off the power supply of the acoustic imaging device;

[0077] Measure the power consumption of the thermal imaging in real time, determine whether the thermal imaging module is in an active working state according to the thermal imaging power consumption, and combine the current battery level with the thermal imaging power consumption. If it is in an inactive working state, turn off the power supply of the thermal imaging device.

[0078] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. Adaptive power supply regulation method for acoustic thermal imager, characterized in that, It includes the following steps: Measure the surface temperature and output voltage of the lithium battery. When the surface temperature exceeds the set protection temperature, control the lithium battery to stop output, and estimate the current power based on the state of charge estimation model using the output voltage; Measure the power consumption of the acoustic imaging in real time. Judge whether the acoustic imaging module is in an active working state according to the acoustic imaging power consumption. Combine the current power with the acoustic imaging power consumption. If it is in an inactive working state, turn off the power of the acoustic imaging device; Measure the power consumption of the thermal imaging in real time. Judge whether the thermal imaging module is in an active working state according to the thermal imaging power consumption. Combine the current power with the thermal imaging power consumption. If it is in an inactive working state, turn off the power of the thermal imaging device; If the current power is low, the power main control module of the lithium battery turns off the devices in the inactive working state.

2. The adaptive power supply regulation method of the acoustic thermal imager according to claim 1, wherein The method for estimating the current power based on the state of charge estimation model using the output voltage includes: Establish a mapping table of the output voltage and charging state of the lithium battery at different temperatures through experiments, and perform compensation in combination with the real-time surface temperature. The expression is: where the output voltage of the lithium battery is U out , the surface temperature of the lithium battery is T, the state of charge of the lithium battery is SOC, and the experimental calibration coefficients are β, μ, and α respectively; When the load fluctuates, introduce the current integration method to correct the error of voltage hysteresis. The expression is: Among them, the corrected state of charge of the lithium battery is The initial time is t o , the nominal capacity of the lithium battery is D nom , the current of the lithium battery at time t is i(t), and the state of charge of the lithium battery calculated based on the open circuit voltage is SOC OCV ; Divide the surface temperature into multiple intervals. Each interval uses a different mapping table of output voltage and charging state. Record the capacity decay curve caused by the aging of the lithium battery, dynamically adjust the parameters of the state of charge estimation model, and output the adjusted mapping table of state of charge and charging state as the current power.

3. The adaptive power supply adjustment method of the acoustic thermal imager according to claim 1, characterized in that The method for judging whether the acoustic imaging module is in an active working state according to the acoustic imaging power consumption includes: Capture the transient power fluctuation at ultra-high frequency based on the acoustic imaging power consumption, and use the Butterworth filter and wavelet denoising to separate the high-frequency noise and the effective signal; Use the short-time Fourier transform to divide the time window, analyze the spectral energy distribution, capture the power characteristics of the periodic working mode, and use the Hamming weight difference to calculate the power consumption difference caused by the input change of the characteristic module; Resample and align the non-uniformly used power data set, establish a probability model according to the historical data, dynamically update the power variance threshold of the active state, and use the trapezoidal formula integration method to detect the instantaneous perturbation of the second derivative mutation; If the power consumption difference shows a specific fluctuation change, the acoustic imaging module is in an active state; if the power consumption difference remains stable for a long time or the power is close to the baseline noise, the acoustic imaging module is in an inactive state.

4. The adaptive power supply adjustment method of the acoustic thermal imager according to claim 1, characterized in that The method for judging whether the thermal imaging module is in an active working state according to the thermal imaging power consumption includes: Collect the working temperature of the thermal imaging module, select a short-time window to capture the instantaneous mutation, and calculate the mean square rate and the maximum deviation rate: μ(U) = μ o ·(1 + ζ(U - U ref )) where the standard deviation of the thermal imaging power consumption is σ, and the variance of the thermal imaging power consumption is σ 2 , the mean value of the thermal imaging power consumption is μ, and the mean square rate is The maximum deviation rate is The maximum thermal imaging power consumption within the time window is H max , the minimum thermal imaging power consumption within the time window is H min , the operating temperature of the thermal imaging module is U, and the reference temperature is U ref , the temperature compensation coefficient is ζ, and the mean power consumption at room temperature is μ o , the standard deviation of the sensor noise is σ noise ; When the mean square rate is greater than 1.2 and the maximum deviation rate is greater than 0.6, the thermal imaging module is in an active state; in a high-temperature environment, correct the mean value μ according to the temperature sensor data. If the ambient temperature is greater than 40 degrees, adjust the thresholds of the mean square rate and the maximum deviation rate, and the mean square rate is greater than 0.9 and the maximum deviation rate is greater than 0.

4.

5. An adaptive power supply regulation system for a thermoacoustic imager for performing the method according to any one of claims 1-4, characterized in that, It includes a lithium battery, a voltage acquisition module, a temperature measurement module, an acoustic imaging power consumption measurement module, a thermal imaging power consumption measurement module, an acoustic imaging power switch module, a thermal imaging power switch module, and a power main control module; The temperature measurement module measures the surface temperature of the lithium battery; the voltage measurement module measures the output voltage of the battery; The power supply main control module obtains the surface temperature of the lithium battery through the temperature measurement module, and when the temperature exceeds the set protection temperature, controls the lithium battery to stop output; the power supply main control module obtains the output voltage of the lithium battery through the voltage measurement module and estimates the current power according to the voltage; The sound imaging power consumption of the sound imaging is measured in real time, and it is judged whether the sound imaging module is in an active working state according to the sound imaging power consumption. According to the current power combined with the sound imaging power consumption, if it is in an inactive working state, the power supply of the sound imaging device is turned off; The thermal imaging power consumption of the thermal imaging is measured in real time, and it is judged whether the thermal imaging module is in an active working state according to the thermal imaging power consumption. According to the current power combined with the thermal imaging power consumption, if it is in an inactive working state, the power supply of the thermal imaging device is turned off.

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