Redundancy flight control actuation system and redundancy flight control actuation control method

Abstract

The invention provides a redundancy flight control actuation system and a redundancy flight control actuation control method, and belongs to the technical field of flight control systems.In the system, an LVDT displacement demodulation module converts an LVDT alternating current feedback signal output by an actuator into a first direct current electric signal in proportional relation with the output displacement of the actuator; the LVDT sum value demodulation module is used for converting an LVDT alternating current feedback signal output by the actuator into a fixed direct current signal; the electric signal is converted into a local servo channel LVDT digital signal which can be processed by the FPGA module through the A / D module, the FPGA module processes the local servo channel LVDT digital signal and the same type of LVDT digital signals from multiple external servo channels and then outputs a voted LVDT digital signal, and the D / A module converts the signal into a voted LVDT analog signal. The subtractor carries out subtraction on the analog signal and a servo instruction from the FCC and then outputs a corresponding voltage signal, and the U / I current driving module converts the voltage signal into a current signal needed for driving the actuator to work. Vecting processing and channel fault logic of redundant signals are achieved through the FPGA, other links of position servo control are achieved through the analog circuit, the characteristics of high reliability and high response of the analog circuit are reserved, and the defect that control hardware is complex due to the fact that redundant servo control is achieved through a pure analog circuit is overcome.

Description

Technical Field

[0001] The present invention belongs to the technical field of flight control systems, and in particular relates to a redundant flight control actuation system and a redundant flight control actuation control method. Background Art

[0002] Since the flight control system adopts fly-by-wire control technology, redundant fly-by-wire flight control systems are usually used to ensure the safety of the flight control system. The flight control actuation system is an important part of the flight control system, and its reliability and safety are extremely important.

[0003] Currently, most fly-by-wire flight control actuation systems use analog servo control technology or digital servo control technology. Both technologies have their own advantages and disadvantages. When analog servo control technology is used, the system has the advantages of reliable operation, high frequency response and good verifiability, but it is difficult to debug or modify the control algorithm. Moreover, when the system has electrical triple or quadruple redundancy, the control circuit is complex, which will lead to a decrease in the basic reliability of the system. When digital servo control technology is used, the system has the advantages of convenient debugging or modification of the control algorithm and simple control circuit, but the control software verification is complex. If the verification is not sufficient or there are software bugs, the system may easily lose its servo control function and even endanger flight safety. Summary of the invention

[0004] In order to solve the problem that the fly-by-wire flight control actuation system in the prior art mostly adopts analog servo control or digital servo control with reduced reliability and low flight safety. The present invention provides a redundant flight control actuation system and a redundant flight control actuation control method, which can ensure that the system has the advantage of fast response, and at the same time can effectively reduce the hardware complexity of the servo control unit, reduce the difficulty of product development and debugging, improve the reliability of system operation, and reduce the development cost of the product. It can be used in the development of redundant fly-by-wire flight control actuation systems for helicopters or fixed-wing aircraft. The technical solution is as follows:

[0005] In a first aspect, a redundant flight control actuation system is provided, comprising: an LVDT displacement demodulation module 1, an LVDT sum demodulation module 2, an A / D module 3, an FPGA module 4, a D / A module 5, a subtractor 6, a U / I current drive module 8, and an actuator 10; the LVDT displacement demodulation module 1 is connected to the actuator 10 and the A / D module 3, the LVDT sum demodulation module 2 is connected to the actuator 10 and the A / D module 3, the A / D module 3, the FPGA module 4, the D / A module 5, the subtractor 6, the U / I current drive module 8, and the actuator 10 are connected in sequence, and the subtractor 6 is connected to an external FCC,

[0006] The LVDT displacement demodulation module 1 converts the LVDT AC feedback signal output by the actuator 10 into a first DC signal that is proportional to the output displacement of the actuator 10; the LVDT sum demodulation module 2 converts the LVDT AC feedback signal output by the actuator 10 into a fixed DC signal; the first DC signal and the fixed DC signal are converted into the servo channel LVDT digital signal that can be processed by the FPGA module 4 through the A / D module 3, and the FPGA module 4 processes the servo channel LVDT digital signal and the LVDT digital signal of the same type from the external multiple servo channels through the internal redundancy LVDT feedback signal voting algorithm, and then outputs the voted LVDT digital signal, the D / A module 5 converts the voted LVDT digital signal into a voted LVDT analog signal, the subtractor 6 subtracts the voted LVDT analog signal and the servo instruction from the FCC and then outputs the corresponding voltage signal, and the U / I current drive module 8 converts the voltage signal into the current signal required to drive the actuator 10 to work.

[0007] The actuator 10 includes: an ESV 11 and a LVDT 12 , the LVDT 12 outputs an LVDT AC feedback signal, and the U / I current driving module 8 converts the voltage signal output by the subtractor 6 into a current signal required to drive the ESV 11 to work.

[0008] Among them, the LVDT displacement demodulation module 1, the LVDT sum demodulation module 2, the subtractor 6, the KP module 7, the U / I current drive module 8, and the current limiting module 9 all adopt analog circuits, which have the characteristics of fast signal response and high operation reliability.

[0009] Furthermore, the redundant flight control actuation system also includes a KP module 7 located between the subtractor 6 and the U / I current driving module 8, which is used to amplify the voltage signal output by the subtractor 6 to ensure the rapid responsiveness of the system to small-amplitude voltage signals.

[0010] Furthermore, the redundant flight control actuation system also includes a current limiting module 9 located between the U / I current driving module 8 and the actuator 10, which is used to limit the current signal output by the U / I current driving module 8 to ensure that the maximum output current meets the rated current required to drive the ESV11 to work.

[0011] In a second aspect, a redundant flight control actuation control method is provided, which is used in any system described in the first aspect, and the method comprises:

[0012] The LVDT displacement demodulation module 1 converts the LVDT AC feedback signal output by the actuator 10 into a DC signal proportional to the output displacement of the actuator 10;

[0013] The LVDT sum demodulation module 2 converts the LVDT AC feedback signal output by the actuator 10 into a fixed DC signal;

[0014] The A / D module 3 converts the DC signal and the fixed DC signal into a servo channel LVDT digital signal that can be processed by the FPGA module 4;

[0015] The FPGA module 4 processes the LVDT digital signal of the servo channel and the LVDT digital signal of the same type from the external multiple servo channels through the internal redundancy LVDT displacement feedback signal voting algorithm, and then outputs the voted LVDT digital signal;

[0016] The D / A module 5 converts the voted LVDT digital signal into the voted LVDT analog signal;

[0017] Subtractor 6 performs subtraction on the LVDT analog signal after voting and the servo command from the external FCC and then outputs the corresponding voltage signal;

[0018] The U / I current driving module 8 converts the voltage signal into a current signal required to drive the actuator 10 to work.

[0019] Among them, the FPGA module 4 processes the LVDT digital signal of the servo channel and the LVDT digital signal of the same type from the external multiple servo channels through the internal redundancy LVDT feedback signal voting algorithm, and then outputs the voted LVDT digital signal, including:

[0020] When the LVDT digital signal of the current servo channel and the LVDT digital signals of the same type from the external multi-servo channels are both valid, or both are invalid, the average of the second largest value and the second smallest value is taken as the LVDT digital signal after voting;

[0021] When three redundancies are valid in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multi-servo channels, the middle value of the valid three redundancies is used as the LVDT digital signal after voting;

[0022] When two redundancies are valid in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multi-servo channels, the average of the two valid redundancies is used as the LVDT digital signal after voting;

[0023] When there is a valid single redundancy in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multiple servo channels, the single redundancy is used as the LVDT digital signal after voting.

[0024] Among them, when the variation range of the fixed DC signal output by the LVDT and value demodulation module 2 is within the preset range, the first LVDT digital signal is determined to be valid; when the variation range of the fixed DC signal output by the LVDT and value demodulation module 2 is not within the preset range, the first LVDT digital signal is determined to be invalid; wherein the first LVDT digital signal is any LVDT digital signal of the servo channel LVDT digital signal and the LVDT digital signal of the same type from multiple external servo channels.

[0025] The beneficial effects of the present invention are at least:

[0026] The present invention proposes a redundant flight control actuation system and a redundant flight control actuation control method. The core control unit of the system is FPGA. The technical characteristics of FPGA are utilized to implement the voting processing of redundant signals and channel fault logic through FPGA. The other links of position servo control are implemented through analog circuits, which retain the high reliability and high response characteristics of analog circuits and reduce the disadvantages of complex control hardware brought about by the use of pure analog circuits to implement redundant servo control. Moreover, compared with the DSP+FPGA architecture commonly used in conventional flight control actuation systems, the DSP and its related peripheral circuits are reduced, which not only reduces the hardware cost of the servo channel, but also avoids the problems of software programming and debugging verification brought about by the use of DSP, and reduces the workload of system product development. At the same time, compared with the conventional redundant LVDT feedback signal voting algorithm, the redundant LVDT feedback signal voting algorithm proposed by the present invention not only reduces the voting operation amount of the redundant LVDT feedback signal, but also improves the reliability of system operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of the composition of a quadruple-redundant flight control actuation system of the present invention;

[0028] Figure 2 The present invention is a flow chart of a quadruple-redundant LVDT feedback signal voting method. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution 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. Obviously, the described embodiments are 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 work are within the scope of protection of the present invention.

[0030] The features and illustrative embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed to provide a comprehensive understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is by no means limited to any specific settings and methods proposed below, but covers any improvements, replacements and modifications of structures, methods, devices without departing from the spirit of the present invention. In the accompanying drawings and the following description, known structures and technologies are not shown to avoid unnecessary ambiguity in the present invention.

[0031] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other, and the embodiments can refer to and quote each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0032] The present invention is further described in detail below through specific implementation modes and drawings.

[0033] See also Figure 1 The present invention provides a redundant flight control actuation system, comprising: an LVDT displacement demodulation module 1, an LVDT sum demodulation module 2, an A / D module 3, an FPGA module 4, a D / A module 5, a subtractor 6, a U / I current drive module 8, and an actuator 10; the LVDT displacement demodulation module 1 is connected to the actuator 10 and the A / D module 3, the LVDT sum demodulation module 2 is connected to the actuator 10 and the A / D module 3, the A / D module 3, the FPGA module 4, the D / A module 5, the subtractor 6, the U / I current drive module 8, and the actuator 10 are connected in sequence, and the subtractor 6 is connected to an external FCC.

[0034] The LVDT displacement demodulation module 1 converts the LVDT AC feedback signal output by the actuator 10 into a first DC signal that is proportional to the output displacement of the actuator 10; the LVDT sum demodulation module 2 converts the LVDT AC feedback signal output by the actuator 10 into a fixed DC signal; the first DC signal and the fixed DC signal are converted into the servo channel LVDT digital signal that can be processed by the FPGA module 4 through the A / D module 3, and the FPGA module 4 processes the servo channel LVDT digital signal and the LVDT digital signal of the same type from the external multiple servo channels through the internal redundancy LVDT feedback signal voting algorithm, and then outputs the voted LVDT digital signal, the D / A module 5 converts the voted LVDT digital signal into a voted LVDT analog signal, the subtractor 6 subtracts the voted LVDT analog signal and the servo instruction from the FCC and then outputs the corresponding voltage signal, and the U / I current drive module 8 converts the voltage signal into the current signal required to drive the actuator 10 to work.

[0035] In one embodiment, see Figure 1 The actuator 10 includes: ESV11 and LVDT12, LVDT12 outputs LVDT AC feedback signal, and U / I current driving module 8 converts the voltage signal output by subtractor 6 into the current signal required to drive ESV11 to work.

[0036] In one embodiment, the LVDT displacement demodulation module 1, the LVDT sum demodulation module 2, the subtractor 6, the KP module 7, the U / I current driving module 8, and the current limiting module 9 all adopt analog circuits, which have the characteristics of fast signal response and high operation reliability.

[0037] In one embodiment, see Figure 1 The redundant flight control actuation system also includes a KP module 7 located between the subtractor 6 and the U / I current driving module 8, which is used to amplify the voltage signal output by the subtractor 6 to ensure the rapid responsiveness of the system to small-amplitude voltage signals.

[0038] In one embodiment, see Figure 1 The redundant flight control actuation system also includes a current limiting module 9 located between the U / I current driving module 8 and the actuator 10, which is used to limit the current signal output by the U / I current driving module 8 to ensure that the maximum output current meets the rated current required to drive the ESV11 to work.

[0039] See also Figure 1 An embodiment of the present invention further provides a redundant flight control actuation control method, the method comprising:

[0040] The LVDT displacement demodulation module 1 converts the LVDT AC feedback signal output by the actuator 10 into a DC signal proportional to the output displacement of the actuator 10;

[0041] The LVDT sum demodulation module 2 converts the LVDT AC feedback signal output by the actuator 10 into a fixed DC signal;

[0042] The A / D module 3 converts the DC signal and the fixed DC signal into a servo channel LVDT digital signal that can be processed by the FPGA module 4;

[0043] The FPGA module 4 processes the LVDT digital signal of the servo channel and the LVDT digital signal of the same type from the external multiple servo channels through the internal redundancy LVDT displacement feedback signal voting algorithm, and then outputs the voted LVDT digital signal;

[0044] The D / A module 5 converts the voted LVDT digital signal into the voted LVDT analog signal;

[0045] Subtractor 6 performs subtraction on the LVDT analog signal after voting and the servo command from the external FCC and then outputs the corresponding voltage signal;

[0046] The U / I current driving module 8 converts the voltage signal into a current signal required to drive the actuator 10 to work.

[0047] Among them, the FPGA module 4 processes the LVDT digital signal of the servo channel and the LVDT digital signal of the same type from the external multiple servo channels through the internal redundancy LVDT feedback signal voting algorithm, and then outputs the voted LVDT digital signal, including:

[0048] When the LVDT digital signal of the current servo channel and the LVDT digital signals of the same type from the external multi-servo channels are both valid, or both are invalid, the average of the second largest value and the second smallest value is taken as the LVDT digital signal after voting;

[0049] When three redundancies are valid in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multi-servo channels, the middle value of the valid three redundancies is used as the LVDT digital signal after voting;

[0050] When two redundancies are valid in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multi-servo channels, the average of the two valid redundancies is used as the LVDT digital signal after voting;

[0051] When there is a valid single redundancy in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multiple servo channels, the single redundancy is used as the LVDT digital signal after voting.

[0052] Among them, when the variation range of the fixed DC signal output by the LVDT and value demodulation module 2 is within the preset range, the first LVDT digital signal is determined to be valid; when the variation range of the fixed DC signal output by the LVDT and value demodulation module 2 is not within the preset range, the first LVDT digital signal is determined to be invalid; wherein the first LVDT digital signal is any LVDT digital signal of the servo channel LVDT digital signal and the LVDT digital signal of the same type from multiple external servo channels.

[0053] Figure 1 The composition and connection form of servo channel 1#, servo channel 2#, and servo channel 3# are the same as those of the present servo channel. The embodiment of the present invention is described by taking a quad-redundant flight control actuation system and a quad-redundant LVDT feedback signal voting algorithm as examples.

[0054] like Figure 1 As shown, the LVDT displacement demodulation module 1 converts the LVDT AC feedback signal output by the LVDT 12 on the actuator 10 into a DC signal that is proportional to the output displacement of the actuator 10, and the LVDT sum demodulation module 2 converts the LVDT AC feedback signal output by the LVDT 12 on the actuator 10 into a fixed DC signal. The aforementioned DC signal and the fixed DC signal are converted into digital signals that can be processed by the FPGA module 4 through the A / D module 3, and are processed by the four-redundant LVDT feedback signal voting algorithm (such as Figure 2 The LVDT digital signal after voting is output after processing, and then converted into the LVDT analog signal after voting through the D / A module 5. The subtractor 6 compares the LVDT analog signal after voting with the FCC servo instruction and outputs the corresponding voltage signal. The KP module 7 amplifies the above voltage signal to ensure the system's rapid responsiveness to small voltage signals. The U / I current drive module 8 converts the amplified voltage signal into the current signal required for the ESV11 on the drive actuator 10 to work, and limits the above current signal through the current limiting module 9 to ensure that the maximum output current meets the rated current required for the ESV11 to work.

[0055] In order to reduce the complexity of the quadruple-redundant LVDT displacement feedback signal voting algorithm, improve the reliability of system operation, and reduce the workload of system verification, the quadruple-redundant LVDT feedback signal voting algorithm is designed as follows: Figure 2As shown, the validity of the LVDT feedback signal is only judged by the variation range of the fixed DC signal output by the LVDT and value demodulation module 2 corresponding to the servo channel. When the output fixed DC signal is within the preset range, the LVDT feedback signal is valid. When the variation range of the output fixed DC signal is not within the preset range, the LVDT feedback signal is invalid. There are only five output results at most through this algorithm, and only division is needed to obtain the voting value of the four-redundant LVDT feedback signal or the two-redundant LVDT feedback signal; while the voting algorithm of the conventional four-redundant signal is shown in Table 1, which not only needs to perform three subtractions on the four-redundant LVDT displacement demodulation signals, but also has eight output results at most. If there is a singular fault (2:2 or 1:1:1:1) in the output result, the fault signal cannot be eliminated, thereby affecting the control accuracy of the flight control actuation system and even the flight safety.

[0056] Table 1 Conventional four-redundancy signal voting algorithm

[0057]

[0058] The advantage of the technical solution of the present invention is that, by adopting this solution, the flight control actuation system has the characteristics of simple servo channel composition, high reliability, low cost, fast system response, and simple voting algorithm for redundant LVDT feedback signals, small amount of calculation, high output result credibility, and small system verification workload.

[0059] The above only expresses the implementation mode of the present invention, and its description is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. In addition, the parts not detailed in the present invention are all conventional technologies.

Claims

1. A redundant flight control actuation system, characterized in that: include: LVDT displacement demodulation module (1), LVDT sum value demodulation module (2), A / D module (3), FPGA module (4), D / A module (5), subtractor (6), U / I current drive module (8), actuator (10); the LVDT displacement demodulation module (1) is connected to the actuator (10) and the A / D module (3); the LVDT sum value demodulation module (2) is connected to the actuator (10) and the A / D module (3); the A / D module (3), the FPGA module (4), the D / A module (5), the subtractor (6), the U / I current drive module (8), and the actuator (10) are connected in sequence; the subtractor (6) is connected to an external FCC; The LVDT displacement demodulation module (1) converts the LVDT AC feedback signal output by the actuator (10) into a first DC signal proportional to the output displacement of the actuator (10); the LVDT sum demodulation module (2) converts the LVDT AC feedback signal output by the actuator (10) into a fixed DC signal; the first DC signal and the fixed DC signal are converted into the servo channel LVDT digital signal that can be processed by the FPGA module (4) through the A / D module (3); the FPGA module (4) processes the servo channel LVDT digital signal and the LVDT digital signal of the same type from the external multiple servo channels through the internal redundant LVDT feedback signal voting algorithm and outputs the voted LVDT digital signal; the D / A module (5) converts the voted LVDT digital signal into a voted LVDT analog signal; the subtractor (6) performs a difference between the voted LVDT analog signal and the servo instruction from the FCC and outputs a corresponding voltage signal; the U / I current drive module (8) converts the voltage signal into a current signal required to drive the actuator (10) to work.

2. The system according to claim 1, characterized in that The actuator (10) comprises an ESV (11) and an LVDT (12), wherein the LVDT (12) outputs an LVDT AC feedback signal, and the U / I current driving module (8) converts the voltage signal output by the subtractor (6) into a current signal required for driving the ESV (11) to work.

3. The system according to claim 1, characterized in that The LVDT displacement demodulation module (1), the LVDT sum value demodulation module (2), the subtractor (6), the KP module (7), the U / I current driving module (8) and the current limiting module (9) all adopt analog circuits.

4. The system according to claim 1, characterized in that The redundant flight control actuation system also includes a KP module (7) located between the subtractor (6) and the U / I current drive module (8), which is used to amplify the voltage signal output by the subtractor (6).

5. The system according to claim 1, characterized in that The redundant flight control actuation system further comprises a current amplitude limiting module (9) located between the U / I current driving module (8) and the actuator (10), and is used for performing amplitude limiting processing on the current signal output by the U / I current driving module (8).

6. A redundant flight control actuation control method, characterized in that: For use in the system according to any one of claims 1 to 5, the method comprises: The LVDT displacement demodulation module (1) converts the LVDT AC feedback signal output by the actuator (10) into a first DC signal that is proportional to the output displacement of the actuator (10); The LVDT sum demodulation module (2) converts the LVDT AC feedback signal output by the actuator (10) into a fixed DC signal; The A / D module (3) converts the first DC signal and the fixed DC signal into a servo channel LVDT digital signal that can be processed by the FPGA module (4); The FPGA module (4) processes the LVDT digital signal of the servo channel and the LVDT digital signals of the same type from multiple external servo channels through an internal redundant LVDT displacement feedback signal voting algorithm, and then outputs the LVDT digital signal after voting; The D / A module (5) converts the voted LVDT digital signal into a voted LVDT analog signal; The subtractor (6) performs subtraction on the LVDT analog signal after voting and the servo command from the external FCC and then outputs a corresponding voltage signal; The U / I current driving module (8) converts the voltage signal into a current signal required for driving the actuator (10) to work.

7. The method according to claim 6, characterized in that The FPGA module (4) processes the LVDT digital signal of the servo channel and the LVDT digital signals of the same type from the external multiple servo channels through the internal redundant LVDT feedback signal voting algorithm, and then outputs the voted LVDT digital signal, including: When the LVDT digital signal of the current servo channel and the LVDT digital signals of the same type from the external multi-servo channels are both valid, or both are invalid, the average of the second largest value and the second smallest value is taken as the LVDT digital signal after voting; When three redundancies are valid in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multi-servo channels, the middle value of the valid three redundancies is used as the LVDT digital signal after voting; When two redundancies are valid in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multi-servo channels, the average of the two valid redundancies is used as the LVDT digital signal after voting; When there is a valid single redundancy in the LVDT digital signal of the current servo channel and the LVDT digital signal of the same type from the external multiple servo channels, the single redundancy is used as the LVDT digital signal after voting.

8. The method according to claim 7, characterized in that When the variation range of the fixed DC signal output by the LVDT and value demodulation module (2) is within a preset range, the first LVDT digital signal is determined to be valid; when the variation range of the fixed DC signal output by the LVDT and value demodulation module (2) is not within the preset range, the first LVDT digital signal is determined to be invalid; wherein the first LVDT digital signal is any LVDT digital signal of the servo channel LVDT digital signal and LVDT digital signals of the same type from external multiple servo channels.

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