A voting method for dual-channel sensor signals of aircraft engines based on frequency domain characteristics

Abstract

The present invention relates to a voting method for dual-channel sensor signals of an aircraft engine based on frequency domain characteristics, comprising the following steps: collecting dual-channel sensor signals, performing high-pass filtering and low-pass filtering on the dual-channel sensor signals to obtain high-frequency and low-frequency signals; setting an initial low-frequency signal health level for the low-frequency signals of the dual-channels, and adjusting the low-frequency signal health level according to preset low-frequency signal health judgment conditions; setting an initial high-frequency signal health level for the high-frequency signals of the dual-channels, and adjusting the high-frequency signal health level according to preset high-frequency signal health judgment conditions; and performing signal voting based on the adjusted low-frequency signal health level and high-frequency signal health level of the dual-channels to select a trusted channel from the dual-channels. The present invention can accurately detect and isolate sensor signal anomalies such as glitches, small jumps, and drifts caused by poor electrical contact during engine operation, significantly improving the safety of aircraft engine operation.

Description

Technical Field

[0001] The present invention belongs to the technical field of aero-engines, and in particular relates to a voting method for aero-engine dual-channel sensor signals based on frequency domain characteristics. Background Art

[0002] Aircraft engine sensors primarily include speed sensors, temperature sensors, and pressure sensors. The aircraft engine electronic controller uses these sensors to collect state parameters such as engine speed, cross-section temperature, and pressure to implement control functions such as steady-state control, acceleration and deceleration control, and parameter limit protection, thereby achieving thrust regulation and safe operation across the entire engine envelope.

[0003] Aircraft engine sensors generally adopt a dual-channel design, such as Figure 2 The sensor contains two components, Component A and Component B, which pass through cables A and B respectively and then enter the engine electronic controller for signal voting, which is then used for control calculation and control output.

[0004] Failure modes such as electrical damage to internal sensor components, poor contact between plugs and sockets, and cable damage can all lead to sensor signal distortion. Aircraft engine airworthiness regulations stipulate that the design and construction of control systems must ensure that unsafe conditions will not occur due to a single failure or malfunction of the control system's electrical or electronic components.

[0005] When an engine experiences electrical damage to internal sensor components, cable damage leading to loose or disconnected connections, or poor contact due to loose plugs and sockets or oil immersion, the engine's inherent high-frequency vibrations can cause the circuit to be equivalent to the original sensor, with an additional low-impedance circuit connected in series at high frequency. This can cause the sensor signal to exhibit glitches, small jumps, and drift. Existing dual-channel sensor signal voting methods simply compare and select the two-channel signals, often failing to effectively detect and isolate abnormal signals. This can lead to the use of abnormal signals for control, causing engine control fluctuations, loss of thrust (LOTC), and even overheating and overspeed, impacting aircraft engine flight safety.

[0006] In summary, the existing dual-channel sensor signal voting method has insufficient coverage of fault modes and the problem of being unable to detect and isolate faults. It is hoped that an improved voting method for dual-channel aircraft engine sensor signals based on frequency domain characteristics will be proposed without changing the existing engine hardware configuration. This method can accurately detect and isolate abnormal signals caused by poor signal contact during aircraft engine operation, thereby improving the safety of aircraft engine operation. Summary of the Invention

[0007] The present invention provides a voting method for dual-channel sensor signals of an aircraft engine based on frequency domain characteristics to detect and isolate abnormal sensor signals and select sensor signals with high credibility as control sources, thereby solving the technical problems existing in the background technology.

[0008] The technical solution of the present invention is as follows: comprising:

[0009] S10: collecting dual-channel sensor signals, performing high-pass filtering and low-pass filtering on the dual-channel sensor signals respectively, and obtaining high-frequency signals and low-frequency signals;

[0010] S20: setting an initial low-frequency signal health level for the low-frequency signals of the dual channels, and adjusting the low-frequency signal health level according to a preset low-frequency signal health judgment condition;

[0011] S30: setting an initial high-frequency signal health level for the high-frequency signals of the dual channels, and adjusting the high-frequency signal health level according to a preset high-frequency signal health judgment condition;

[0012] S40: performing signal voting based on the low-frequency signal health and the high-frequency signal health after adjustment of the dual channels, and selecting a trusted channel from the dual channels;

[0013] S50: Determine the final selected signal based on the signal of the trusted channel.

[0014] Furthermore, the method for obtaining the high-frequency signal and the low-frequency signal in step S10 includes:

[0015] The dual-channel sensor signal is low-pass filtered to form a low-frequency signal y(k);

[0016] The low-pass filtering method is:

[0017] a(0)·y(k)=b(0)·x(k)+b(1)·x(k-1)+……+b(n)·x(kn)

[0018] -a(1)·y(k-1)-……-a(n)·y(kn)

[0019] Wherein, y(k) represents the low-frequency signal of the current cycle, y(kn) represents the low-frequency signal of the previous n cycles, x(k) represents the collected value of the sensor signal of the current cycle, x(kn) represents the collected value of the sensor signal of the previous n cycles, n is the order of the low-pass filter, which is an integer greater than or equal to 1, a(0), a(1), ... a(n) and b(0), b(1), ... b(n) are all filter coefficients;

[0020] The sensor signal is high-pass filtered to form a high-frequency signal yy(k);

[0021] The high-pass filtering method is:

[0022] aa(0)·yy(k)=bb(0)·x(k)+bb(1)·x(k-1)+……+bb(m)·x(km)

[0023] -aa(1)·yy(k-1)-……-aa(m)·yy(km)

[0024] Among them, yy(k) represents the high-frequency signal of the current cycle, yy(km) represents the high-frequency signal of the previous m cycles, x(k) represents the collected value of the sensor signal of the current cycle, x(km) represents the collected value of the sensor signal of the previous m cycles, m is the filter order, which is an integer greater than or equal to 1, and aa(0), aa(1), ... aa(m) and bb(0), bb(1), ... bb(m) are all filter coefficients.

[0025] Furthermore, the low-frequency signal health judgment condition in S20 includes:

[0026] When y(k)>Δ1 or y(k)<Δ2, the low-frequency signal health is set to -2;

[0027] When |y(k)-y(k-1)|>Δ3, the low-frequency signal health is set to -2;

[0028] In other cases, the health of the low-frequency signal in this cycle remains the health of the low-frequency signal in the previous cycle;

[0029] The initial value of the low-frequency signal health is 1, and Δ1, Δ2, and Δ3 are all judgment thresholds.

[0030] Furthermore, the high frequency signal health judgment condition in S30 includes:

[0031] If |yy(k)|>Δ4, the high-frequency signal health is reduced by 2;

[0032] If |yy(k)|>Δ4 is ​​not satisfied, the high-frequency signal healthiness increases by 1;

[0033] The initial value of the high-frequency signal health is 1, and Δ4 is ​​the judgment threshold.

[0034] Furthermore, the S40 includes:

[0035] If the low-frequency signal health of the two channels is not equal, the channel with the larger low-frequency signal health value is selected as the trusted channel, and the number of trusted channels is 1;

[0036] If the low-frequency signal health of the two channels is equal and the high-frequency signal health of the two channels is unequal, the channel with the larger high-frequency signal health value is selected as the trusted channel, and the number of trusted channels is 1;

[0037] If the health of the low-frequency signals of the two channels is equal and the health of the high-frequency signals of the two channels is equal, both channels are used as trusted channels, and the number of trusted channels is 2.

[0038] Furthermore, the S50 includes:

[0039] If the number of trusted channels is 1, the low-frequency signal of the trusted channel is selected as the final selected signal;

[0040] If the number of trusted channels is 2, the low-frequency signals of the two channels are averaged and used as the final selected signal.

[0041] Beneficial effects of the present invention: The present invention performs low-pass filtering and high-pass filtering on the dual-channel sensor signals, obtains low-frequency signals within the engine response frequency band and high-frequency signals outside the engine response frequency band from the frequency domain perspective, and calculates the signal health of the low-frequency signals and high-frequency signals. According to the signal frequency domain characteristics, a comprehensive signal vote is performed on the health of the low-frequency signals and the health of the high-frequency signals of the dual channels to determine the final selected signal. The present invention can accurately detect and isolate abnormalities such as sensor signal glitches, small jumps and drifts caused by poor electrical contact during engine operation, significantly improving the safety of aircraft engine operation. The present invention is implemented using a software method, which does not change the existing engine sensor and electronic controller hardware configuration, saving manufacturing costs. At the same time, this method has low computational complexity and low time consumption, and is suitable for real-time operation in the engine electronic controller. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a flow chart of the present invention.

[0043] Figure 2 This is a schematic diagram of the principle of using dual-channel sensor signals in aircraft engine control systems.

[0044] Figure 3 is a flow chart of an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0046] Figure 2 This is the schematic diagram of the dual-channel sensor signal in the aircraft engine control system. Figure 2 The signal voting method, in an embodiment of the present invention, Figure 1 and Figure 3 The specific steps of the aircraft engine dual-channel sensor signal voting method based on frequency domain characteristics are given, such as Figure 1 and Figure 3 As shown, the present invention includes:

[0047] S10: collecting dual-channel sensor signals, performing high-pass filtering and low-pass filtering on the dual-channel sensor signals respectively, and obtaining high-frequency signals and low-frequency signals.

[0048] Among them, specifically Figure 2 As shown, the engine electronic controller collects dual-channel sensor signals respectively.

[0049] The sensor signal is low-pass filtered to form a low-frequency signal y(k).

[0050] The low-pass filtering method is:

[0051] a(0)·y(k)=b(0)·x(k)+b(1)·x(k-1)+……+b(n)·x(kn)

[0052] -a(1)·y(k-1)-……-a(n)·y(kn)

[0053] Among them, y(k) represents the low-frequency signal of the current cycle, y(kn) represents the low-frequency signal of the previous n cycles, x(k) represents the collected value of the sensor signal of the current cycle, x(kn) represents the collected value of the sensor signal of the previous n cycles, n is the order of the low-pass filter, which is an integer greater than or equal to 1, and a(0), a(1), ...a(n) and b(0), b(1), ...b(n) are all filter coefficients.

[0054] Regarding the low-pass filter design, the cutoff frequency can be set to 1.5 to 2 times of the actual engine response bandwidth, and the filter order n can be set to 2 to 6.

[0055] The sensor signal is high-pass filtered to form a high-frequency signal yy(k).

[0056] The high-pass filtering method is:

[0057] aa(0)·yy(k)=bb(0)·x(k)+bb(1)·x(k-1)+……+bb(m)·x(km)

[0058] -aa(1)·yy(k-1)-……-aa(m)·yy(km)

[0059] Among them, yy(k) represents the high-frequency signal of the current cycle, yy(km) represents the high-frequency signal of the previous m cycles, x(k) represents the collected value of the sensor signal of the current cycle, x(km) represents the collected value of the sensor signal of the previous m cycles, m is the filter order, which is an integer greater than or equal to 1, and aa(0), aa(1), ... aa(m) and bb(0), bb(1), ... bb(m) are all filter coefficients.

[0060] Regarding high-pass filter design considerations, the high-pass filter can be designed based on a cutoff frequency of 2.5 to 3 times the engine response frequency, and the filter order m can be set to 2 to 6.

[0061] S20: setting an initial low-frequency signal health level for the dual-channel low-frequency signals, and adjusting the low-frequency signal health level according to a preset low-frequency signal health judgment condition.

[0062] The specific conditions for judging the health of low-frequency signals are as follows:

[0063] If |y(k)-y(k-1)|>Δ1, the low-frequency signal health is set to -1;

[0064] If y(k)>Δ2 or y(k)<Δ3, the low-frequency signal health is set to -2;

[0065] In other cases, the health of the low-frequency signal in this cycle remains the health of the low-frequency signal in the previous cycle;

[0066] The initial value of the low-frequency signal health is 1, and Δ1, Δ2, and Δ3 are all judgment thresholds.

[0067] In terms of the design considerations of the judgment threshold, the maximum change rate of the sensor signal, the maximum acquisition value of the sensor signal, and the minimum acquisition value of the sensor signal under the engine working conditions are used, while leaving a certain margin, as the values ​​of Δ1, Δ2, and Δ3 respectively.

[0068] S30: setting an initial high-frequency signal health level for the high-frequency signals of the dual channels, and adjusting the high-frequency signal health level according to a preset high-frequency signal health judgment condition.

[0069] The specific conditions for judging the health of high-frequency signals are as follows:

[0070] If |yy(k)|>Δ4, the high-frequency signal health is reduced by 2;

[0071] If |yy(k)|>Δ4 is ​​not satisfied, the high-frequency signal healthiness increases by 1;

[0072] If the high-frequency signal health is less than -5, the high-frequency signal health is set to -5; if the high-frequency signal health is greater than 5, the high-frequency signal health is set to 5.

[0073] The initial value of the high-frequency signal health is 1, and Δ4 is ​​the judgment threshold.

[0074] Regarding the design considerations of the judgment threshold, a certain margin is reserved as the value of Δ4 based on the high-frequency noise characteristics of the sensor signal and the requirements of the engine's steady-state thrust fluctuation indicator for sensor acquisition accuracy.

[0075] S40: Perform signal voting based on the low-frequency signal health and the high-frequency signal health after adjustment of the dual channels, and select a trusted channel from the dual channels.

[0076] If the low-frequency signal health of the two channels is not equal, the channel with the larger low-frequency signal health value is selected as the trusted channel, and the number of trusted channels is 1;

[0077] If the low-frequency signal health of the two channels is equal and the high-frequency signal health of the two channels is unequal, the channel with the larger high-frequency signal health value is selected as the trusted channel, and the number of trusted channels is 1;

[0078] If the health of the low-frequency signals of the two channels is equal and the health of the high-frequency signals of the two channels is equal, both channels are used as trusted channels, and the number of trusted channels is 2.

[0079] S50: Calculate and obtain the final control selection signal according to the signal of the trust channel.

[0080] If the number of trusted channels is 1, the low-frequency signal of the trusted channel is selected as the final selected signal;

[0081] If the number of trusted channels is 2, the low-frequency signals of the two channels are averaged and used as the final selected signal.

[0082] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A voting method for aircraft engine dual-channel sensor signals based on frequency domain characteristics, characterized in that: include: S10: collecting dual-channel sensor signals, performing high-pass filtering and low-pass filtering on the dual-channel sensor signals respectively, and obtaining high-frequency signals and low-frequency signals; S20: setting an initial low-frequency signal health level for the low-frequency signals of the dual channels, and adjusting the low-frequency signal health level according to a preset low-frequency signal health judgment condition; S30: setting an initial high-frequency signal health level for the high-frequency signals of the dual channels, and adjusting the high-frequency signal health level according to a preset high-frequency signal health judgment condition; S40: performing signal voting based on the low-frequency signal health and the high-frequency signal health after adjustment of the dual channels, and selecting a trusted channel from the dual channels; S50: Determine the final selected signal based on the signal of the trusted channel; The S40 includes: If the low-frequency signal health of the two channels is not equal, the channel with the larger low-frequency signal health value is selected as the trusted channel, and the number of trusted channels is 1; If the low-frequency signal health of the two channels is equal and the high-frequency signal health of the two channels is unequal, the channel with the larger high-frequency signal health value is selected as the trusted channel, and the number of trusted channels is 1; If the health of the low-frequency signals of the two channels is equal and the health of the high-frequency signals of the two channels is equal, both channels are used as trusted channels, and the number of trusted channels is 2.

2. The voting method for aircraft engine dual-channel sensor signals based on frequency domain characteristics according to claim 1, characterized in that: The method for obtaining high-frequency signals and low-frequency signals in S10 includes: The dual-channel sensor signal is low-pass filtered to form a low-frequency signal ; The low-pass filtering method is: , in, Represents the low-frequency signal of this cycle, Before n Periodic low-frequency signal, Indicates the collected value of the sensor signal in this cycle, Before The collected value of the sensor signal of the period, is the low-pass filter order, an integer greater than or equal to 1, 、 、…… as well as 、 、…… are filter coefficients; The sensor signal is high-pass filtered to form a high-frequency signal ; The high-pass filtering method is: ， in, Represents the high-frequency signal of this cycle, Before Periodic high-frequency signal, Indicates the collected value of the sensor signal in this cycle, Before The collected value of the sensor signal of the period, is the filter order, an integer greater than or equal to 1, 、 、…… as well as 、 、…… are filter coefficients.

3. The voting method for aircraft engine dual-channel sensor signals based on frequency domain characteristics according to claim 2, characterized in that: The health judgment conditions of the low-frequency signal in S20 include: when or When , the low-frequency signal health is set to -2; when When , the low-frequency signal health is set to -2; In other cases, the health of the low-frequency signal in this cycle remains the health of the low-frequency signal in the previous cycle; The initial value of the low-frequency signal health is 1. 、 、 Both are judgment thresholds.

4. The voting method for aircraft engine dual-channel sensor signals based on frequency domain characteristics according to claim 2, characterized in that: The high frequency signal health judgment conditions in S30 include: If satisfied , the high-frequency signal health is reduced by 2; If not satisfied , the high-frequency signal health increases by 1; Among them, the initial value of the high-frequency signal health is 1. is the judgment threshold.

5. The voting method for aircraft engine dual-channel sensor signals based on frequency domain characteristics according to claim 1, characterized in that: The S50 includes: If the number of trusted channels is 1, the low-frequency signal of the trusted channel is selected as the final selected signal; If the number of trusted channels is 2, the low-frequency signals of the two channels are averaged and used as the final selected signal.

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