Secondary power supply module detection device

Abstract

The invention relates to the technical field of secondary power supply module voltage and current detection in an electric propulsion system, in particular to a secondary power supply module detection device. The secondary power supply module detection device comprises a voltage measurement unit, a Hall current sensor and a Rogowski coil. The voltage measurement unit comprises a differential filter circuit and a voltage probe, wherein one end of the voltage probe is connected with the output end of the differential filter circuit. The voltage measuring unit, the Hall current sensor and the Rogowski coil are all arranged in a vacuum chamber where a secondary power supply module in the electric propulsion system is located; wherein the voltage measuring unit, the Hall current sensor and the Rogowski coil are respectively used for measuring the voltage, the small current and the large current of a secondary power supply module in a vacuum cabin in the electric propulsion system, and the small current is 1t; 1 kA, and the large current gt; 1 kA. The voltage and current of the secondary power supply module in the cabin can be accurately measured, and the antenna effect is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of voltage and current detection of a secondary power module in an electric propulsion system, and in particular relates to a secondary power module detection device. Background Art

[0002] The electric propulsion system is mainly composed of thrusters, secondary power modules (power processing units PPU) and storage and supply units. Among them, the core function of PPU is to convert the voltage and power of the satellite's primary bus into various voltages and powers required for the operation of the electric propulsion system when the satellite is in orbit, and to electrically isolate the primary bus from the electric propulsion system. During operation, PPU receives control instructions from the control system, executes the on / off control of its multiple single-machine power supply circuits, supplies power to the electric propulsion system, and provides the voltage and current required for heating, electric field maintenance and beam extraction under different working conditions. As a special power supply, PPU has the characteristics of multiple topological structures (voltage-stabilized source, current-stabilized source and high-voltage pulse output power supply, etc.), large output power, high output voltage and low-voltage power supply floating high-voltage operation. As a power supply and an important component of the electric propulsion system, the normal operation and reliability level of PPU directly determine the working state of the electric propulsion system and the on-orbit life of the entire satellite. Therefore, it is necessary to test PPU during the development of the electric propulsion system.

[0003] The existing detection technology for measuring the working voltage of the thruster is to use a wire to connect the PPU output end in the vacuum cabin with the oscilloscope outside the cabin through the cabin flange. The discharge current is measured by placing the probe outside the cabin. Due to the antenna effect, the voltage at the PPU output end is amplified after being transmitted to the outside of the cabin through a certain distance of wire, resulting in large measurement errors. In addition, the amplified voltage will also damage the components inside the PPU in the cabin. Summary of the invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, the present application aims to provide a secondary power module detection device.

[0005] According to an embodiment of the present invention, there is provided a secondary power module detection device, comprising:

[0006] A voltage measuring unit, comprising a differential filter circuit and a voltage probe having one end connected to an output end of the differential filter circuit, wherein the voltage measuring unit is disposed in a vacuum chamber where a secondary power supply module in the electric propulsion system is located;

[0007] A Hall current sensor is arranged in a vacuum chamber where a secondary power module is located in the electric propulsion system;

[0008] A Rogowski coil is arranged in a vacuum chamber where a secondary power module is located in the electric propulsion system;

[0009] Among them, the voltage measurement unit, the Hall current sensor, and the Rogowski coil are respectively used to measure the voltage, small current, and large current of the secondary power module in the vacuum cabin of the electric propulsion system, wherein the small current is <1kA, and the large current is >1kA.

[0010] In some embodiments, the differential filtering circuit includes an operational amplifier, a signal input anti-interference module for maintaining the symmetry and balance of the input signal, a signal feedback module for frequency selection and filtering characteristic control, and a signal calibration module for input impedance matching and signal balance stabilization, wherein the operational amplifier has an input terminal, an output terminal, a positive power supply terminal and a negative power supply terminal, the input terminal includes an inverting input terminal and a non-inverting input terminal, the negative power supply terminal of the operational amplifier is grounded, the signal input anti-interference module is connected in series between the input terminal of the operational amplifier and the voltage output terminal of the secondary power supply module, the signal feedback module is connected in parallel between the inverting input terminal and the output terminal of the operational amplifier, and the signal calibration module is connected in parallel with the non-inverting input terminal of the operational amplifier.

[0011] In some embodiments, the signal input anti-interference module includes a first resistor and a second resistor with equal resistance values, one end of the first resistor and the second resistor are electrically connected to the inverting input terminal and the non-inverting input terminal of the operational amplifier, respectively, and the other ends of the first resistor and the second resistor are electrically connected to the voltage output terminal of the secondary power supply module.

[0012] In some embodiments, the signal feedback module includes a third resistor and a first capacitor, and the third resistor and the first capacitor are connected in parallel between the inverting input terminal and the output terminal of the operational amplifier.

[0013] In some embodiments, the signal calibration module includes a fourth resistor and a second capacitor, and both the fourth resistor and the second capacitor are connected in parallel to the non-inverting input terminal of the operational amplifier.

[0014] In some embodiments, an oscilloscope is further included, and the voltage measuring unit is connected in series between the output terminal of the secondary power module and the input terminal of the oscilloscope.

[0015] In some embodiments, the Hall current sensor passes through a wire between the secondary power module and the oscilloscope.

[0016] In some embodiments, the Rogowski coil passes through a wire between the secondary power supply module and the oscilloscope.

[0017] In some embodiments, the voltage measurement unit further includes an adaptive filtering module for optimizing the signal input to the differential filtering circuit, wherein the adaptive filtering module is constructed based on the input signal and the statistical characteristics of the noise, and the adaptive filtering module includes:

[0018] The continuous time signal containing the useful signal and Gaussian white noise is recorded as y(t). The specific structure of y(t) is as follows:

[0019] y(t)=s(t)+n(t)

[0020] Among them, s(t) is the signal component, n(t) is the zero-mean Gaussian white noise;

[0021] Given a known noise power spectral density S n Under the condition of (f), design an adaptive filter so that the output signal separated from the input signal y(t) Can be as close to the original signal s(t) as possible;

[0022] In the process of constructing the basic formula of adaptive filtering, the Fourier transform of the input signal y(t) is Y(f) using frequency domain analysis, and the target signal The reconstruction formula can be expressed as:

[0023]

[0024] Where W(f) is the transfer function of the adaptive filter, which represents the gain of different frequency components; -j2πft is a complex exponential basis function, which describes the inverse transform of the frequency domain signal in the time domain;

[0025] Y(f) is the frequency domain representation of the signal s(t), obtained by Fourier transform:

[0026] Y(f)=S(f)+N(f)

[0027] Where S(f) is the spectrum of the signal s(t), and N(f) is the spectrum of the noise n(t);

[0028] W(f) is defined based on the power spectral density of the signal and noise as:

[0029]

[0030] Among them, S s (f) is the power spectral density of the signal, which describes the energy distribution of the signal in the frequency domain; S n (f) is the power spectral density of the noise.

[0031] In some embodiments, it further includes a shell located at the periphery of the secondary power module detection device and defining an internal space of the secondary power module detection device, and the voltage measurement unit, the Hall current sensor and the Rogowski coil are all arranged on the shell.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) In the prior art, when measuring the voltage of the secondary power module, a wire is used to connect the output end of the secondary power module in the vacuum cabin with an oscilloscope outside the cabin through a cabin flange. Due to the antenna effect, the exposed wire will collect charged particles in the plasma, resulting in an increase in potential, which makes the voltage measured by the oscilloscope outside the cabin suddenly rise, so that the voltage and current measurement of the secondary power module are inaccurate. At the same time, the high voltage will also damage the internal chips and other components of the secondary power module, causing the circuit to fail. In order to solve this technical problem, the secondary power module detection device of the present invention is configured in the vacuum cabin where the secondary power module is located in the electric propulsion system, and the secondary power module detection device is configured with a voltage measurement unit, a Hall current sensor and a Rogowski coil to achieve the measurement of the voltage, small current and large current of the secondary power module in the electric propulsion system, thereby improving the accuracy of the voltage and current measurement of the secondary power module. Specifically, the voltage measurement unit is responsible for monitoring the voltage level of the secondary power module, the Hall current sensor is used to measure small currents less than 1kA, and the Rogowski coil is used to measure large currents greater than 1kA. This design enables the configuration of the secondary power module detection device to cover a wide range from low current to high current, effectively meeting the measurement requirements of different current levels of the secondary power module, and ensuring multi-angle and all-round monitoring of the secondary power module;

[0034] (2) The voltage measurement unit in the present invention combines a differential filter circuit and a voltage probe, which can improve the measurement accuracy of the existing secondary power module voltage. In the electric propulsion system, voltage stability is crucial to the safety of the system; the measurement unit can accurately obtain the voltage data of the power module, which helps to detect voltage anomalies or fluctuations in a timely manner, prevent equipment damage or system failures caused by voltage anomalies, and improve the reliability and safety of the electric propulsion system;

[0035] (3) The device measures small currents (less than 1kA) by configuring a Hall current sensor in a vacuum chamber. The Hall current sensor has high measurement accuracy, fast response, and good anti-interference ability. Traditionally, current sensors are usually placed outside the chamber, which increases the difficulty of installation and maintenance. By placing the Hall current sensor in the chamber, the present invention can not only improve the measurement accuracy, but also reduce the error caused by long-distance signal transmission, while ensuring the safety and stability of the measurement process;

[0036] (4) The present invention measures large currents (greater than 1kA) by configuring a Rogowski coil in a vacuum chamber. Compared with the Hall current sensor, the present invention has better dynamic response capability and can accurately measure high-frequency currents. In addition, the Hall current sensor is larger in size and more expensive when measuring large currents. The use of a Rogowski coil can effectively reduce the size and cost of the device while meeting the high-frequency measurement requirements of large currents.

[0037] (5) The Hall current sensor and Rogowski coil in the present invention are respectively used to measure the small current and large current of the secondary power module, ensuring that high-precision monitoring can be maintained even when the current changes greatly; dedicated sensors with different current ranges can effectively avoid sensor saturation or unsuitability, thereby achieving stable secondary power module current measurement;

[0038] (6) All voltage measurement units, Hall current sensors and Rogowski coils are installed in the vacuum chamber of the electric propulsion system. Since the secondary power module usually works in a vacuum environment, this design fully considers its special working conditions and ensures the reliability of the secondary power module in a vacuum environment. The secondary power module can operate stably in a special environment, avoiding the common electronic equipment in a vacuum environment. Failure or signal loss due to the secondary power module;

[0039] (7) The secondary power module detection device of the present invention can monitor the voltage and current changes of the secondary power module in the electric propulsion system in real time. Through continuous monitoring, it can quickly discover faults such as power anomalies, power fluctuations or current overloads in the system, which helps to provide timely warnings to effectively avoid subsequent problems caused by power failures and improve the stability and safety of the electric propulsion system.

[0040] (8) The present invention integrates the voltage measurement unit, the Hall current sensor and the Rogowski coil into one device in the cabin. The secondary power module detection device can not only realize the multifunctional measurement of voltage, small current and large current, but also reduce the complexity in the traditional design. All measuring devices are arranged in the cabin, avoiding the potential interference and errors caused by the long wire connection and the external arrangement of the equipment in the traditional solution, making the electric propulsion system design more concise and more convenient to install and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the scheme in the embodiment of the present invention, the following is a brief introduction to the drawings required for describing the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 is a structural diagram of a secondary power supply module detection device according to an embodiment of the present invention when in operation;

[0043] Figure 2 is a structural diagram of a differential filter circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0045] The existing detection technology for measuring the working voltage of the thruster is to use a wire to connect the output end of the secondary power module in the vacuum cabin with the oscilloscope outside the cabin through the cabin flange. The discharge current is measured by placing the probe outside the cabin. Due to the antenna effect, the voltage at the output end of the secondary power module is amplified after being transmitted to the outside of the cabin through a certain distance of wire, resulting in a large measurement error. In addition, the amplified voltage will also damage the components inside the secondary power module in the cabin.

[0046] In order to overcome the shortcomings of the above-mentioned secondary power module voltage and current detection technology, the present invention provides a secondary power module detection device, which can not only accurately monitor the voltage and current of the secondary power module in the electric propulsion system, but also has high adaptability and can work stably in a vacuum environment, thereby ensuring the efficient operation of the electric propulsion system within different current ranges.

[0047] Taking the circuit board energy storage capacitor voltage test as an example, the traditional test steps are: 1. Lead out a cable at the positive and negative ends of the circuit board energy storage capacitor; 2. Use a high-voltage probe or high-voltage sensor to directly connect to the lead-out cables; 3. Read the data measured by the high-voltage probe to obtain the voltage value. However, the traditional test method is prone to "antenna effect" in the cable that is led out at the beginning, and the influence of the external environment coupling and the high background noise make the test accuracy not meet the requirements.

[0048] The detection device innovatively proposed by the present invention has an adaptive filtering function. On the basis of reducing the influence of environmental noise, it can also ensure the authenticity of signal data and greatly improve the test accuracy. The following is the data statistics through actual test comparison.

[0049] Table 1 Comparison of circuit board energy storage capacitor voltage detection effects

[0050] Serial number Traditional method / V The present invention / V Design value / V Accuracy improvement effect 1 810.5 801.3 800 1.31％→0.16％ 2 813.6 800.6 800 1.70％→0.08％ 3 812.7 800.3 800 1.59％→0.04％ 4 815.2 800.9 800 1.90％→0.11％ 5 814.1 801.1 800 1.76％→0.14％ 6 809.2 800.7 800 1.15％→0.09％ 7 810.2 801.2 800 1.28％→0.15％ 8 809.8 800.7 800 1.23％→0.09％

[0051] like Figure 1 As shown, in some embodiments, a secondary power module detection device is provided, and the secondary power module detection device includes: a voltage measurement unit, a Hall current sensor 3 and a Rogowski coil 4.

[0052] Among them, the voltage measurement unit includes a differential filter circuit 2 and a voltage probe 1, one end of the voltage probe 1 is connected to the output end of the differential filter circuit 2, the differential filter circuit 2 can output a stable and real voltage value, and the voltage probe 1 can measure the voltage value of the secondary power supply module.

[0053] Among them, the voltage measurement unit, the Hall current sensor 3, and the Rogowski coil 4 are respectively used to measure the voltage, small current, and large current of the secondary power module in the vacuum cabin of the electric propulsion system, among which the small current is <1kA, and the large current is >1kA.

[0054] The voltage measurement unit, the Hall current sensor 3 and the Rogowski coil 4 are all arranged in the vacuum chamber where the secondary power module of the electric propulsion system is located;

[0055] The power supply is electrically connected to the secondary power supply module to provide power to the secondary power supply.

[0056] In the secondary power module detection device, the differential filter circuit 2 is configured to work with components such as the Hall current sensor 3 and the Rogowski coil 4 to improve the measurement accuracy. The Hall sensor can provide data on the current intensity, while the Rogowski coil 4 is used to detect changes in the magnetic field, and both may be subject to electromagnetic interference. The role of the differential filter circuit 2 is to eliminate these interferences to ensure that the measured voltage and current values ​​are more accurate and reduce errors caused by noise.

[0057] If the differential filter circuit 2 is not used, for example, single-channel filtering is used directly or there is no filtering strategy specifically for this type of composite signal, the following problems may occur:

[0058] a. Interference amplification: Unfiltered noise may cause large fluctuations in measurement results, especially when the sensor receives strong electromagnetic interference, which may significantly affect the stability and reliability of current and voltage readings.

[0059] b. Distorted signal: Noise may introduce nonlinear effects, causing the signal to deform during transmission, making the resolved real current or voltage information unclear.

[0060] c. Reduced signal-to-noise ratio: Lack of effective filtering will cause the useful components in the original signal to be submerged in the noise, reducing the proportion of effective data and affecting subsequent analysis and decision-making.

[0061] Therefore, through comparative experiments, it can be seen that the measurement results after using the differential filtering circuit have higher accuracy and stability, and can better reflect the actual current and voltage conditions, which is crucial for the precise control of the electric propulsion system.

[0062] In some embodiments, it also includes a shell 5 located at the periphery of the secondary power module detection device and determining the internal space of the secondary power module detection device, and the voltage measurement unit, the Hall current sensor 3 and the Rogowski coil 4 are all arranged on the shell 5. An electrical interface is left on the shell 5, which is connected to the power supply, the voltage probe 1, the Hall current sensor 3, and the Rogowski coil 4 respectively. The secondary power module detection device can select different shell 5 materials according to different working requirements and environments. The working environment of the thruster system is complex, and factors such as magnetic fields, radiation, single particles, and electromagnetics can cause interference to the thruster. Therefore, the detection device proposed in the present invention can select different shell 5 materials according to specific protection requirements. For example, 1J22 material can be magnetically shielded, tantalum skin can be anti-oxidation, electromagnetic shielding materials or ordinary stainless steel, aluminum, plastic and other materials.

[0063] In some embodiments, the secondary power module detection device also includes an oscilloscope, and the voltage measuring unit is connected in series between the output end of the secondary power module and the input end of the oscilloscope. The oscilloscope can display the voltage and current of the secondary power module in real time, such as the voltage value of the secondary power module measured by the voltage measuring unit, and the current value of the secondary power module measured by the Hall current sensor 3 and the Rogowski coil 4.

[0064] In some embodiments, the Hall current sensor 3 passes through the wire between the secondary power module and the oscilloscope, and can detect the small discharge current of the secondary power module.

[0065] In some embodiments, the Rogowski coil 4 passes through the wire between the secondary power module and the oscilloscope, and can detect the large discharge current of the secondary power module.

[0066] There are some technical challenges (technical barriers) in applying differential filter circuits in electric propulsion systems, such as signal noise interference: small thrust changes in electric propulsion systems may be affected by environmental noise, which makes accurate measurement difficult. Differential filter circuits need to handle this Gaussian noise and some possible nonlinear interference;

[0067] The differential filter circuit 2 needs to adopt a unique structural design to distinguish it from the common filters on the market. This differentiation can be in the following aspects (the technical points involved in one or more aspects will be described in detail in some embodiments below):

[0068] (1) Customized design: To meet the special requirements of electric propulsion systems, such as low noise, fast response, or enhanced anti-interference capabilities, specific sensor input processing units such as adaptive gain control can be added;

[0069] (2) Parallel processing: To reduce latency and improve real-time performance, a parallel processing architecture is used to decompose computing tasks into multiple processors or hardware modules to accelerate the data processing process;

[0070] (3) Dedicated hardware: Embedded hardware circuits optimized for electric propulsion applications, such as dedicated digital signal processing integrated circuits, improve computing speed and energy efficiency;

[0071] (4) Adaptive algorithm: Considering the dynamic changes of the system, an adaptive filtering algorithm may be used, such as a particle filter or a variation of the Kalman filter, which can automatically adjust the filter parameters to adapt to changes in environmental conditions.

[0072] (5) Optimized order or structure: The order or structure of the filter is designed to be more streamlined, reducing unnecessary computational burden while maintaining good filtering effect.

[0073] like Figure 2 As shown, in some embodiments, the differential filter circuit includes an operational amplifier 6, a signal input anti-interference module for maintaining the symmetry and balance of the input signal, a signal feedback module for frequency selection and filter characteristic control, and a signal calibration module for input impedance matching and signal balance stability, wherein the operational amplifier 6 has an input terminal, an output terminal, a positive power supply terminal and a negative power supply terminal, the input terminal includes an inverting input terminal and a non-inverting input terminal, the negative power supply terminal of the operational amplifier 6 is grounded, the signal input anti-interference module is connected in series between the input terminal of the operational amplifier 6 and the voltage output terminal of the secondary power supply module, the signal feedback module is connected in parallel between the inverting input terminal and the output terminal of the operational amplifier 6, and the signal calibration module is connected in parallel with the non-inverting input terminal of the operational amplifier 6. The differential filter circuit 2 utilizes the common-mode suppression principle of the operational amplifier 6, can effectively suppress common-mode interference signals (such as power supply noise, electromagnetic interference, etc.), and only extracts the differential signal (the difference between the two input signals). This is particularly important when it is necessary to process the output voltage of the secondary power supply with more interference, so the differential filter circuit 2 can accurately measure the voltage of the secondary power supply module in the cabin to avoid the antenna effect.

[0074] In some embodiments, the signal input anti-interference module includes a first resistor 7 and a second resistor 8 of equal resistance, one end of the first resistor 7 and the second resistor 8 are electrically connected to the inverting input terminal and the non-inverting input terminal of the operational amplifier 6, respectively, and the other ends of the first resistor 7 and the second resistor 8 are electrically connected to the voltage output terminal of the secondary power supply module. The signal input anti-interference module divides the output voltage of the secondary power supply (the interfered input signal) and establishes a 1:1 resistance ratio at the inverting input terminal and the non-inverting input terminal of the operational amplifier 6 to ensure the differential characteristics of the input signal and avoid the generation of additional unbalanced signals at the input terminal.

[0075] In some embodiments, the signal feedback module includes a third resistor 9 and a first capacitor 11, and the third resistor 9 and the first capacitor 11 are connected in parallel between the inverting input terminal and the output terminal of the operational amplifier 6. The signal feedback module provides a negative feedback network to control the gain of the operational amplifier 6 so that the circuit has a stable operating point; the first capacitor 11 and the third resistor 9 work together to form a low-pass filter to filter out high-frequency noise and ensure the frequency response characteristics of the circuit.

[0076] In some embodiments, the signal calibration module includes a fourth resistor 10 and a second capacitor 12, and the fourth resistor 10 and the second capacitor 12 are connected in parallel to the in-phase input terminal of the operational amplifier 6. The signal calibration module provides a frequency selection function at the input terminal, attenuates high-frequency interference in the in-phase input signal, and cooperates with the signal feedback module to jointly optimize the frequency response and stability of the circuit.

[0077] In some embodiments, the voltage measurement unit further includes an adaptive filtering module for optimizing the signal of the input differential filtering circuit, the adaptive filtering module is constructed based on the input signal and the statistical characteristics of the noise, and the adaptive filtering module includes:

[0078] The continuous time signal containing the useful signal and Gaussian white noise is recorded as y(t). The specific structure of y(t) is as follows:

[0079] y(t)=s(t)+n(t)

[0080] Among them, s(t) is the signal component, which is usually the target reconstructed signal; n(t) is zero-mean Gaussian white noise with statistical independence;

[0081] Given a known noise power spectral density S n Under the condition of (f), design an adaptive filter so that the output signal separated from the input signal y(t) Can be as close to the original signal s(t) as possible;

[0082] 1. Output signal representation of adaptive filter

[0083] In the process of constructing the basic formula of adaptive filtering, the Fourier transform of the input signal y(t) is Y(f) using frequency domain analysis, and the output signal The reconstruction formula can be expressed as:

[0084]

[0085] Where W(f) is the transfer function of the adaptive filter, which represents the gain of different frequency components; -j2πft is a complex exponential basis function, which describes the inverse transform of the frequency domain signal in the time domain;

[0086] Y(f) is the frequency domain representation of the signal s(t), obtained by Fourier transform:

[0087] Y(f)=S(f)+N(f)

[0088] Where S(f) is the spectrum of the original signal s(t), and N(f) is the spectrum of the noise n(t);

[0089] 2. Design of adaptive filter

[0090] W(f) is defined based on the power spectral density of the signal and noise as:

[0091]

[0092] Among them, S s (f) is the power spectral density of the signal, which describes the energy distribution of the signal in the frequency domain; S n (f) is the power spectral density of the noise;

[0093] 3. Analysis of the properties of adaptive filter transfer function

[0094] The filter transfer function W(f) has the following properties:

[0095] (1) Signal enhancement: When S s (f)>>S n (f), W(f)≈1, and the filter retains the signal within this frequency range;

[0096] (2) Noise suppression: When S s (f)<<S n (f), W(f)≈0, and the filter attenuates noise in this frequency range;

[0097] (3) Smooth transition: The function of the filter is to balance the frequency components of the signal and noise, enhance the dominant frequency of the signal, and suppress the dominant frequency of the noise.

[0098] 4. Estimation of signal power spectral density

[0099] In practical applications, the signal power spectral density S s (f) It is necessary to make an estimate based on the statistical characteristics of the signal s(t).

[0100] For example: In practical applications, S s (f) usually needs to be estimated, that is, assuming that the signal s(t) is stationary, its power spectral density can be obtained by the autocorrelation function R s (τ) calculation:

[0101]

[0102] in, t represents time;

[0103] By counting the signal sample data, S can be approximately estimated s (f).

[0104] The above process shows how to reconstruct the signal s(t) from the noisy signal y(t) by designing an adaptive filter. The design of the adaptive filter is based on the known power spectral density S of the noise. n (f) and the power spectral density S of the signal s (f), by reasonably selecting the filter transfer function W(f), the signal can be effectively extracted from the noise to achieve the purpose of signal recovery. The most important role of the adaptive filtering algorithm is to remove random noise while retaining the real signal. This measure can greatly ensure that the data is not distorted and that the filtered data is highly representative.

[0105] The secondary power module detection device of the present invention is configured in the vacuum chamber where the secondary power module is located in the electric propulsion system, and the secondary power module detection device realizes the measurement of the voltage, small current and large current of the secondary power module in the electric propulsion system by configuring a voltage measurement unit, a Hall current sensor 3 and a Rogowski coil 4, thereby improving the accuracy of the voltage and current measurement of the secondary power module. Specifically, the voltage measurement unit is responsible for monitoring the voltage level of the secondary power module, the Hall current sensor 3 is used to measure small currents less than 1kA, and the Rogowski coil 4 is used to measure large currents greater than 1kA. Such a design enables the configuration of the secondary power module detection device to cover a wide range from low current to high current, effectively meeting the measurement requirements of different current levels of the secondary power module, and ensuring multi-angle and all-round monitoring of the secondary power module;

[0106] The voltage measurement unit of the present invention combines the differential filter circuit 2 and the voltage probe 1, which can improve the measurement accuracy of the existing secondary power module voltage. In the electric propulsion system, voltage stability is crucial to the safety of the system; the measurement unit can accurately obtain the voltage data of the power module, which helps to detect voltage anomalies or fluctuations in time, prevent equipment damage or system failures caused by voltage anomalies, and improve the reliability and safety of the electric propulsion system;

[0107] The present invention measures small currents (less than 1kA) by configuring a Hall current sensor 3 in a vacuum chamber. The Hall current sensor 3 has high measurement accuracy, fast response, and good anti-interference ability. Traditionally, current sensors are usually placed outside the chamber, which increases the difficulty of installation and maintenance. By placing the Hall current sensor 3 in the chamber, the present invention can not only improve the measurement accuracy, but also reduce the error caused by long-distance signal transmission, while ensuring the safety and stability of the measurement process;

[0108] The present invention measures large currents (greater than 1 kA) by configuring a Rogowski coil 4 in a vacuum chamber. Compared with the Hall current sensor 3, the present invention has better dynamic response capability and can accurately measure high-frequency currents. In addition, since the Hall current sensor 3 is larger in size and more expensive when measuring large currents, the use of the Rogowski coil 4 can effectively reduce the size and cost of the device while meeting the high-frequency measurement requirements of large currents.

[0109] In the present invention, the Hall current sensor 3 and the Rogowski coil 4 are respectively used for measuring the small current and the large current of the secondary power module, ensuring that high-precision monitoring can be maintained even when the current changes greatly; the dedicated sensors with different current ranges can effectively avoid the situation where the sensor is saturated or unsuitable, thereby realizing stable current measurement of the secondary power module;

[0110] All voltage measurement units, Hall current sensors 3 and Rogowski coils 4 are set in the vacuum chamber of the electric propulsion system. Since the secondary power module usually works in a vacuum environment, this design fully considers its special working conditions and ensures the reliability of the secondary power module in a vacuum environment. The secondary power module can operate stably in special environments, avoiding the common electronic equipment in a vacuum environment. Failure or signal loss due to the secondary power module;

[0111] The secondary power module detection device of the present invention can monitor the voltage and current changes of the secondary power module in the electric propulsion system in real time. Through continuous monitoring, it can quickly discover faults such as power anomalies, power fluctuations or current overloads in the system, which helps to provide timely warnings to effectively avoid subsequent problems caused by power failures and improve the stability and safety of the electric propulsion system.

[0112] The present invention integrates the voltage measurement unit, the Hall current sensor 3 and the Rogowski coil 4 into one device in the cabin. The secondary power module detection device can not only realize the multifunctional measurement of voltage, small current and large current, but also reduce the complexity in the traditional design. All measuring devices are arranged in the cabin, avoiding the potential interference and errors caused by long wire connection and external arrangement of equipment in the traditional solution, making the electric propulsion system design more concise and more convenient to install and maintain.

[0113] The above is only a specific implementation of the present invention and does not limit the protection scope of the present invention. Any person skilled in the art can easily think of fabrications and changes within the technical scope of the present invention, all of which should be included in the protection scope of the present invention. Therefore, the protection scope of the claims should be taken as the protection scope of the present invention.

Claims

1. A secondary power module detection device, characterized in that: include: A voltage measuring unit, comprising a differential filter circuit and a voltage probe having one end connected to an output end of the differential filter circuit, wherein the voltage measuring unit is disposed in a vacuum chamber where a secondary power supply module in the electric propulsion system is located; A Hall current sensor is arranged in a vacuum chamber where a secondary power module is located in the electric propulsion system; A Rogowski coil is arranged in a vacuum chamber where a secondary power module is located in the electric propulsion system; Among them, the voltage measurement unit, the Hall current sensor, and the Rogowski coil are respectively used to measure the voltage, small current, and large current of the secondary power module in the vacuum cabin of the electric propulsion system, wherein the small current is <1kA, and the large current is >1kA.

2. The secondary power module detection device according to claim 1, characterized in that: The differential filter circuit includes an operational amplifier, a signal input anti-interference module for maintaining the symmetry and balance of the input signal, a signal feedback module for frequency selection and filtering characteristic control, and a signal calibration module for input impedance matching and signal balance stabilization, wherein the operational amplifier has an input terminal, an output terminal, a positive power supply terminal and a negative power supply terminal, the input terminal includes an inverting input terminal and a non-inverting input terminal, the negative power supply terminal of the operational amplifier is grounded, the signal input anti-interference module is connected in series between the input terminal of the operational amplifier and the voltage output terminal of the secondary power supply module, the signal feedback module is connected in parallel between the inverting input terminal and the output terminal of the operational amplifier, and the signal calibration module is connected in parallel with the non-inverting input terminal of the operational amplifier.

3. The secondary power module detection device according to claim 2, characterized in that: The signal input anti-interference module includes a first resistor and a second resistor with equal resistance values, one end of the first resistor and the second resistor are electrically connected to the inverting input terminal and the non-inverting input terminal of the operational amplifier, respectively, and the other ends of the first resistor and the second resistor are electrically connected to the voltage output terminal of the secondary power supply module.

4. The secondary power module detection device according to claim 2, characterized in that: The signal feedback module includes a third resistor and a first capacitor, and the third resistor and the first capacitor are connected in parallel between the inverting input terminal and the output terminal of the operational amplifier.

5. The secondary power module detection device according to claim 2, characterized in that: The signal calibration module includes a fourth resistor and a second capacitor, and both the fourth resistor and the second capacitor are connected in parallel to the non-inverting input terminal of the operational amplifier.

6. The secondary power module detection device according to claim 1, characterized in that: An oscilloscope is also included, and the voltage measuring unit is connected in series between the output end of the secondary power supply module and the input end of the oscilloscope.

7. The secondary power module detection device according to claim 6, characterized in that: The Hall current sensor passes through a wire between the secondary power module and the oscilloscope.

8. The secondary power module detection device according to claim 6, characterized in that: The Rogowski coil passes through a wire between the secondary power supply module and the oscilloscope.

9. The secondary power module detection device according to claim 1, characterized in that: The voltage measurement unit further includes an adaptive filtering module for optimizing the signal input to the differential filtering circuit, wherein the adaptive filtering module is constructed based on the input signal and the statistical characteristics of noise, and the adaptive filtering module includes: The continuous time signal containing the useful signal and Gaussian white noise is recorded as y(t). The specific structure of y(t) is as follows: y(t)=s(t)+n(t) Among them, s(t) is the signal component, n(t) is the zero-mean Gaussian white noise; Given a known noise power spectral density S n (t), design an adaptive filter so that the output signal separated from the input signal y(t) Can be as close to the original signal s(t) as possible; In the process of constructing the basic formula of adaptive filtering, the Fourier transform of the input signal y(t) is Y(f) using frequency domain analysis, and the target signal The reconstruction formula can be expressed as: Where W(f) is the transfer function of the adaptive filter, which represents the gain of different frequency components; -j2πft is a complex exponential basis function, which describes the inverse transform of the frequency domain signal in the time domain; Y(f) is the frequency domain representation of the signal s(t), obtained by Fourier transform: Y(t)=S(t)+N(t) Where S(t) is the spectrum of the signal s(t), and N(t) is the spectrum of the noise n(t); W(f) is defined based on the power spectral density of the signal and noise as: Among them, S s (t) is the power spectral density of the signal, which describes the energy distribution of the signal in the frequency domain; S n (t) is the power spectral density of the noise.

10. The secondary power module detection device according to claim 1, characterized in that: It also includes a shell located at the periphery of the secondary power module detection device and defining the internal space of the secondary power module detection device, and the voltage measurement unit, the Hall current sensor and the Rogowski coil are all arranged on the shell.

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