Method for measuring distortion signal of airborne 115V alternating current power supply
The high-frequency distortion signal is separated from the onboard 115V AC power supply through filtering and conditioning circuits, which solves the problem of insufficient real-time measurement accuracy in the prior art, and realizes accurate monitoring and data acquisition of the onboard power supply power supply.
Patent Information
- Application Number
- CN202410561211.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-08
- Publication Date
- 2025-07-25
AI Technical Summary
It is difficult for the prior art to accurately measure the distortion signal of the onboard 115V AC power supply in real time, and the data transmission and conditioning process may affect the measurement accuracy.
The filtering and conditioning method is used to separate the high-frequency distortion signals from the voltage signal, and the signal processing is performed through the third-order filtering circuit and the conditioning circuit, and combined with AD acquisition and data processing, the accurate distortion signal measurement value is obtained.
Real-time monitoring and accurate data acquisition of airborne power supply are realized, and the calculation accuracy of distortion parameters is improved.
Smart Images
Figure FT_1
Abstract
Description
Technical Field
[0001] The present invention belongs to the detection of the quality of the aircraft power supply in the field of flight tests and the real-time monitoring of the aircraft power supply network in the field of aircraft health management, and particularly relates to a method for measuring the distortion signal of the airborne 115V AC power supply. Background Art
[0002] The aircraft airborne power supply includes DC power supplies and AC power supplies. Among them, the DC power supplies include 28V, 270V, 540V, etc., while the current AC power supply is only 115V. In the aircraft power supply environment, the use of many electrical devices will generate interference signals of various frequencies in the aircraft power grid. These interferences will not only interfere with the normal operation of other devices, but may also cause the harmonic compensation device to fail. Therefore, it is of great significance to measure and monitor the distortion signals of the aircraft power supply in real time.
[0003] According to the provisions of the GJB 5189 standard, the distortion signal of the airborne AC power supply can be obtained by collecting the instantaneous voltage signal value of the power supply and performing relevant calculations. The data for the calculation comes from the acquisition of the voltage signal. According to the sampling rate required by the GJB181B standard, the amount of data collected is very large and cannot be transmitted to the ground for processing in real time. At the same time, since the distortion signal is relatively small, when conditioning the voltage value before collecting the voltage signal, it may affect the distortion signal, thereby reducing the accuracy of calculating the distortion parameters.
[0004] The present invention directly separates and collects the high-frequency distortion signal from the voltage signal extracted from the airborne 115V AC power supply, which can provide accurate data for the monitoring of the airborne power supply or the evaluation of the power supply quality. Summary of the Invention
[0005] Extract the voltage signal of the power supply from the airborne 115V AC power supply. Before conditioning the voltage signal, use a filtering and conditioning method to separate and collect the high-frequency distortion signal from the voltage signal.
[0006] The specific implementation steps are as follows: 1. Extract the phase voltages from the airborne 115V AC power supply for distortion signal collection, and use an overvoltage and overcurrent protection circuit. Connect a current-limiting fuse in series at the input for overcurrent protection, and then use a 300V TVS tube to ground for overvoltage clamping. After third-order filtering, connect a 5V TVS tube to protect the rear-end circuit when faults such as short circuits and open circuits occur in the front-end network; 2. Filter the extracted phase voltage signals. Use a third-order high-pass filter circuit to attenuate the 400HZ fundamental wave to 60DB, and the high-pass filter frequency point is 20KHZ, so as to separate and obtain the high-frequency distortion signal; 3. Adopt as attached Figure 1The conditioning circuit shown in (Figure 1 is the high-frequency distortion conditioning circuit of the AC 115V acquisition unit) conditions the separated high-frequency distortion signal, and the voltage conditioning range is: -5.4V to 5.4V. In the circuit, an operational amplifier, 10K, 20K, and 10uF resistor-capacitor networks are used to attenuate the AC signal by 2.7 times to meet the input range of ±2V. A 2.048V DC bias voltage is added and superimposed on the input signal through the BUFF formed by the operational amplifier; IV. After the conditioned signal is collected through the AD, the collected data is processed to obtain the measured value of the distortion signal.
Claims
1. A method for measuring the distortion signal of the airborne 115V AC power supply, characterized in that: Extract a three-phase voltage signal from the airborne 115V AC power supply and obtain the power distortion signal of the airborne 115V AC power supply through a filtering method.
2. The filtering method according to claim 1, characterized in that Perform filtering before signal conditioning of the voltage signal.