Aerodynamic measurement probe and method for controlling such a probe

Abstract

The present invention relates to an aerodynamic measurement probe (10) comprising: - a body (22) comprising a region of interest (25); - a heating element (40) configured to heat the region of interest (25) of said body (22) and comprising an electrical circuit extending through the body (22); - a power supply module configured to power the heating element (40). The probe (10) is characterized in that it further comprises a measurement module configured to generate measurements of the electrical resistance of the electrical circuit, the power supply module being configured to adapt the power supply to the heating element (40) based on the resistance measurements generated by the measurement module.

Description

[0001] TITLE: Aerodynamic measuring probe and method for controlling such a probe

[0002] The present invention relates to an aerodynamic measuring probe.

[0003] The present invention also relates to a method for controlling such a probe. In particular, the probe according to the invention makes it possible to measure at least one of the following quantities: total pressure, static pressure, angle of attack, temperature, velocity, etc. Probes of this type are known as anemobarroclinometric probes.

[0004] The aerodynamic measurement probe can therefore be used in any device exposed to an aerodynamic flow such as an aircraft or a wind turbine.

[0005] The technical problem addressed by the invention is the local accretion of frost on or in aerodynamic measuring probes.

[0006] In aeronautics, measurements acquired by anemobarroclinometric probes are used to facilitate the safe operation of an aircraft in flight. The quality of such flight parameter measurements can be compromised when ice accumulates on the exposed surfaces of the air data probes.

[0007] Such an accumulation of ice can obstruct all or part of the pressure taps or pneumatic tubing of the probe, or hinder the movement of the wind vane and affect the quality of the flight parameters measured.

[0008] To overcome this problem, anemobaroclinometric probes are generally equipped with electric heaters to provide them with defrosting capacity.

[0009] In the current state of the art, there are various ways to heat the probes.

[0010] However, in most cases, the probes are overheated. This can lead to their degradation (corrosion, for example) and premature aging.

[0011] Solutions exist for monitoring the probe's temperature and heating it accordingly (such as installing a thermocouple inside the probe). However, installing a thermocouple in the probe introduces an additional risk of failure.

[0012] Some solutions also measure the current flowing through the probe using, among other things, optocouplers or Hall effect sensors. This allows for verification and monitoring of the current flowing through the heating element. However, optocouplers degrade and become opaque over time, leading to erroneous readings. Furthermore, the performance of Hall effect sensors is degraded at low temperatures (-55°C, for example).

[0013] In summary, existing heating solutions for anemobaroclinometric probes either lack any temperature control, leading to degradation, or are equipped with additional control means, adding in particular a thermocouple, mass and additional complexity.

[0014] The present invention aims to solve this problem and, in particular, to propose heating methods for anemobaroclinometric probes that allow for efficient control of the temperature of these probes, without adding additional control means that could add a thermocouple, mass and / or additional complexity.

[0015] To this end, the invention aims to provide an aerodynamic measuring probe comprising:

[0016] - a body comprising a region of interest;

[0017] - a heating element configured to heat the area of ​​interest of this body and comprising an electrical circuit extending through the body;

[0018] - a power supply module configured to power the heating element;

[0019] the probe being characterized in that it further comprises a measurement module configured to generate electrical resistance measurements of the electrical circuit, the power supply module being configured to adapt the power supply to the heating element according to the resistance measurements generated by the measurement module.

[0020] According to other advantageous aspects of the invention, the probe has one or more of the following characteristics, taken individually or in all technically possible combinations:

[0021] - the electrical circuit is made of a material whose electrical resistance varies with temperature according to a law of variation;

[0022] - the variation law presents an injective function;

[0023] - the power supply module is configured to determine an average temperature of the electrical circuit from electrical resistance measurements;

[0024] - the power supply module is configured to determine a temperature representative of the body or area of ​​interest using a predetermined model, based on the average temperature of the electrical circuit;

[0025] - the power supply module is configured to adjust the variation law and / or the predetermined model according to at least one characteristic of the electrical circuit and / or the body; preferably, the adjustment includes an implementation of an artificial intelligence technique;

[0026] - the power supply module is further configured to compare said representative temperature with a reference temperature in order to deduce a control setpoint for the heating element;

[0027] - the control setpoint includes a setpoint voltage that can be used to power the electrical circuit;

[0028] - The power supply module is configured to impose the setpoint voltage on the electrical circuit by applying pulse width modulation.

[0029] The invention also relates to a method for controlling an aerodynamic measuring probe as defined above, comprising the following steps:

[0030] - generate electrical resistance measurements of the electrical circuit;

[0031] - adapt the power supply to the heating element according to the resistance measurements generated.

[0032] The invention will become clearer upon reading the following description, given solely by way of non-limiting example and with reference to the drawings in which:

[0033] - [Fig. 1] Figure 1 is a schematic cross-sectional view of an aerodynamic measuring probe according to the invention, the probe including in particular control means;

[0034] - [Fig. 2], [Fig. 3] Figures 2 and 3 are detailed views of the control means of Figure 1; and

[0035] - [Fig. 4] is a flowchart of a method for controlling the probe of Figure 1. Figure 1 illustrates an aerodynamic measuring probe 10 according to the invention. This probe 10 can be used in any medium exposed to aerodynamic flows.

[0036] In particular, the probe 10 according to the invention allows to measure at least one of the physical values ​​relating to the medium, such as total pressure, static pressure, incidence, temperature, speed, etc.

[0037] More specifically, according to one embodiment, the measuring probe 10 is an anemobaroclinometric probe which can, for example, measure several of the aforementioned quantities.

[0038] The environment in which the measuring probe 10 is exposed at least partially is in particular a freezing environment, that is to say an environment in which frost accretions are likely to form outside or inside the measuring probe 10.

[0039] The measuring probe 10 is advantageously mounted on the fuselage of an aircraft or on the external part of a wind turbine. An aircraft is defined as any pilotable machine capable of moving through the air. In particular, an aircraft can refer to an airplane, a helicopter, or a drone.

[0040] As illustrated in Figure 1, the measuring probe 10 comprises an internal part 12 to the aircraft fuselage, a base 14 and a measuring element 16.

[0041] The base 14 allows the measuring probe 10 to be fixed to an external surface 20 that is exposed to aerodynamic flows. The external surface 20 is, for example, a surface of the aircraft fuselage. Alternatively, the external surface 20 is an external surface of the wind turbine, such as a blade.

[0042] In some examples, the base 14 may include a plate extending along the outer surface 20 and allowing the base 14 to be fixed to this surface 20.

[0043] The base 14 is fixed to the internal part 12 of the fuselage.

[0044] The measuring element 16 extends from the base 14.

[0045] In the example shown in Figure 1, the measuring element 16 is free to rotate relative to the outer surface 20 and forms, for example, a weather vane. According to other embodiments, the measuring element 16 has a static element relative to the outer surface 20 and is formed, for example, by a mast and a Pitot tube supporting the mast.

[0046] The internal part 12 of the fuselage also extends from the base 14 but in the opposite direction to that of the measuring element 16.

[0047] In particular, the internal part 12 of the fuselage has, for example, a housing intended to be received in a housing formed, for example, in the external surface 20 or, more commonly, in a free volume behind the fuselage of the aircraft whose external part is the surface 20. This housing includes a sensitive part capable of generating a measurement signal following, for example, a movement of the measuring element 16 and a transmitter enabling the transmission of measurement signals to an external system.

[0048] The internal part 12 to the fuselage also includes control means 21 for controlling the operation of at least some components of the measuring probe 10, as will be explained in more detail later.

[0049] In the following description, the base 14 and the measuring element 16 will be considered to form a body 22 of the measuring probe 10. This body 22 may be made of one or more parts of a material. The part or parts are made, for example, of a metal.

[0050] In particular, the body 22 is intended to be exposed to the outside of the object on which the measuring probe 10 is mounted. In other words, the body 22 is exposed to aerodynamic flows. The body 22 defines at least one area of ​​interest 25 in which the formation of frost must be prevented when the body 22 is exposed to aerodynamic flows. In some embodiments, the body 22 defines several distinct areas of interest 25.

[0051] Depending on the nature of the measuring probe 10, the area of ​​interest 25 can extend over an internal and / or external surface of the body 22.

[0052] In the example in Figure 1, the area of ​​interest 25 extends over an outer surface of the wind vane, for example along its leading edge, and over at least part of the outer surface of the base 14. In other words, in this case, the area of ​​interest 25 may have a plurality of distinct sub-areas that may overlap. In the case of a measuring probe including a Pitot tube, an area of ​​interest may extend over an inner and / or outer surface of this Pitot tube and, in some cases, over a part of the inner and / or outer surface of the mast supporting the Pitot tube.

[0053] The measuring probe 10 further includes a heating element 40 which extends through the body 22 so as to heat the area or each area of ​​interest 25. Optionally, the heating element 40 extends near the area or each corresponding sub-area 25. Without loss of generality, only the case of a single heating element 40 and a single area of ​​interest 25 will be described hereafter.

[0054] In one exemplary embodiment, the heating element 40 comprises or consists of a heating wire forming an electrical circuit. The heating wire produces heat by Joule effect, that is, when an electric current passes through it.

[0055] The heating wire includes, in particular, a core made at least partially of an electrically conductive material. In some embodiments, the heating wire has only a core. In such a case, this wire is electrically insulated from the body 22 by an insulating material. According to other embodiments, the heating wire also includes insulation and a sheath surrounding the core. In some embodiments, the heating wire is impregnated so that the impregnation forms electrical insulation. In some embodiments, a heat-shrinkable sheath is used.

[0056] The conductive material forming at least part of the core of the heating wire has an electrical resistance R that varies with its temperature T according to a law of variation. This law of variation therefore has a function R(T).

[0057] Advantageously, the function R(T) is strictly monotonic and injective. It therefore allows us to obtain an inverse function R(T). -1= T(R) is also strictly monotonic. For example, the function T(R) can have a characteristic equation such as:

[0058] T(R) = aR + p

[0059] where the coefficients a, p are known. The function R (T) and in particular the coefficients a, p in the above example can be provided by the supplier of the heating element 40 and / or established during the design of the heating element 40 and / or established during the production or testing phase of the probe 10.

[0060] In some examples, the function R(T) is defined by a plurality of coefficients forming, for example, an abacus.

[0061] For example, the conductive material forming at least part of the core of the heating wire can be copper. Many other metals, alloys, or other elements can exhibit an R(T) function as defined above.

[0062] As an alternative to the heating wire, the heating element 40 may have any other form of an electrical circuit made of a material whose electrical resistance varies with temperature according to a function R(T) as defined above.

[0063] The operation of the heating element 40 is controlled by the control means 21.

[0064] The control means 21 include a measuring module 50 configured to generate electrical resistance measurements of the electrical circuit forming the heating element 40, and a power supply module 52 configured to supply the heating element 40 according to the resistance measurements generated by the measuring module 50.

[0065] An example of a possible implementation of the measurement module 50 is illustrated in figure 2.

[0066] According to this example, the measuring module 50 includes a voltage measuring unit 61 for measuring the voltage of the electrical circuit forming the heating element 40, a current measuring unit 62 for measuring the current flowing through the electrical circuit forming the heating element 40, and a divider 63 for obtaining a resistance value from the voltage measurements from unit 61 and the electric current measurements from unit 62.

[0067] The voltage measuring unit 61 may include, in particular, an operational amplifier operating in differential mode and connected to the terminals of the heating element 40.

[0068] The current measuring unit 62 may include, in particular, a shunt resistor Rshunt connected to one of the terminals of the heating element 40 and enabling the measurement of the current flowing through the electrical circuit forming the heating element 40

[0069] The divider 63 can be implemented in analog or digital form to generate the corresponding voltage measurements.

[0070] The power supply module 52 makes it possible in particular to deduce a representative temperature of the body 22 from the voltage measurements generated by the measurement module 50 and to adapt the power supply of the electrical circuit forming the heating element 40 according to this representative temperature.

[0071] A possible example of the implementation of the power supply module 52 is shown in Figure 3.

[0072] Thus, according to this example, the power supply module 52 includes a conversion unit 71 allowing the representative temperature of the body 22 to be determined from resistance measurements.

[0073] To do this, the conversion unit 71 is connected to the measuring module 50 to receive the resistance measurements generated by this module 50.

[0074] From these resistance measurements, the conversion unit 71 is able to deduce an average temperature of the electrical circuit forming the heating element 40. For this, the conversion unit 71 is able to apply an inverse function of the function R(T) as defined previously.

[0075] From the average temperature, the conversion unit 71 is suitable for determining the representative temperature TR 6P of body 22 using, for example, a predetermined model of body 22 or any other relationship. This model or relationship may, for example, be determined during the design phase of probe 10 or during the testing phase. In some examples, the representative temperature corresponds to the average temperature or is offset from this average temperature by a predetermined constant value. In some cases, the representative temperature of body 22 may correspond to a representative temperature of the area of ​​interest 25.

[0076] In some embodiments, the conversion unit 71 is further configured to adjust the function R(T) and / or the predetermined model of the body 22 according to at least one characteristic of the electrical circuit forming the heating element 40 or, more generally, of the probe 10. This characteristic may be, for example, the age of the element (i.e., aging) or any other operating context of the probe 10. This adjustment may include, for example, the implementation of an artificial intelligence technique. In such a case, a training phase for this technique may be implemented at the factory on a set of probes 10 of the same type.

[0077] The conversion unit 71 can be implemented as a programmable logic circuit, for example of the FPGA (Field-Programmable Gate Array) type, and / or at least partially as software. In the latter case, the conversion module 50 is equipped with a processor for executing this software and memory for storing it.

[0078] The power supply module 52 further includes a first correction unit 72 and a second correction unit 73. The first correction unit 72 is capable of comparing the representative temperature ΔRep with a reference temperature TR to determine a setpoint voltage V cwhich must be applied to the circuit forming the heating element 40 to reach the reference temperature. In particular, the reference temperature TR corresponds, for example, to an optimal body temperature 22 during the operation of the probe 10. In some examples, the reference temperature TR can be adjusted during the operation of the measuring probe 10, using, for example, an artificial intelligence technique similar to that explained previously.

[0079] The second correction unit 73 is capable of comparing the setpoint voltage V c with a measured voltage V m at the terminals of the electrical circuit forming the heating element 40 to determine a voltage difference E.

[0080] Depending on different embodiments, the correction units 72, 73 can form a digital processing chain or an analog processing chain.

[0081] The power supply module 52 finally includes a modulation unit 74 and a power converter 75.

[0082] The modulation unit 74 is capable of controlling the power converter 75 according to the voltage difference E determined by the second correction unit 73, by applying, for example, pulse-width modulation (PWM). The power converter 75 thus allows the setpoint voltage to be imposed across the electrical circuit forming the heating element 40. This power converter 75 can be implemented using any technology that allows energy conversion by raising or lowering the voltage (for example, Buck, Buck-Boost, Boost, flyback, PFC, Sepic, Cuk, etc.).

[0083] The control means 21 are configured to implement a method for controlling the measuring probe 10 which will now be explained with reference to Figure 4 showing a flowchart of these steps.

[0084] Initially, it is assumed that the measuring probe 10 is operational and provides aerodynamic measurements using known techniques. Furthermore, the heating element 40 is supplied with a specific voltage to heat the area of ​​interest 25 of the body 22 and thus prevent frost formation in this area.

[0085] During an initial step 110, the measuring module 50 generates resistance measurements of the electrical circuit forming the heating element 40. For this, the measuring module 50 can use the units 61 to 63 as explained previously.

[0086] In a subsequent step 120, the power supply module 52 adjusts the power supply to the heating element 40 according to the resistance measurements generated by the measuring module 50. Specifically, to do this, the power supply module 52 can first determine an average temperature of the electrical circuit forming the heating element 40 from the resistance measurements generated by the measuring module 50. Then, the power supply module 52 can determine a representative temperature of the body 22 from the average temperature of the electrical circuit. Finally, the power supply module 52 can determine a setpoint voltage required to reach the reference temperature and supply the heating element 40 according to this setpoint voltage.

[0087] Thus, the power supply to the heating element 40 is adjusted to reach the reference temperature. Furthermore, as mentioned previously, one or more artificial intelligence techniques can be applied to adapt at least some of the parameters used during the implementation of the process.

[0088] It is therefore understandable that the present invention offers a number of advantages. In particular, the invention allows for optimal temperature regulation of the probe without adding a thermocouple or any other component.

[0089] Furthermore, the invention allows measurements to be taken as close as possible to the surface to be heated without disrupting the heating of the probe. This is done without adding a sensor to the functional part of the probe (the part that captures the physical quantity measured by the probe) and therefore without degrading its functional characteristics (for example, it does not change the mass of the wind vane, nor its volume, etc.).

[0090] Furthermore, this preserves the available volume inside the probe for the implantation of the heating means and avoids the addition of connections between the functional part of the probe and the avionics.

[0091] The invention presents a generic solution usable on most heating technologies, including in additive manufacturing.

[0092] The invention provides a minimum of complexity to the probe structure and therefore maximum reliability.

[0093] Finally, regulating the probe's temperature throughout the flight allows it to age more slowly, preventing excessive power consumption and overheating of the probe itself. This notably improves flight safety.

Claims

DEMANDS 1. Aerodynamic measuring probe (10) comprising: - a body (22) comprising a region of interest (25); - a heating element (40) configured to heat the area of ​​interest (25) of this body (22) and comprising an electrical circuit extending through the body (22); - a power supply module (52) configured to power the heating element (40); the probe (10) being characterized in that it further comprises a measurement module (50) configured to generate electrical resistance measurements of the electrical circuit, the power supply module (52) being configured to adapt the power supply to the heating element (40) according to the resistance measurements generated by the measurement module (50); and in that: - the electrical circuit is made of a material whose electrical resistance varies with temperature according to a law of variation; - the power supply module (52) is configured to determine an average temperature of the electrical circuit from electrical resistance measurements; and - the power supply module (52) is configured to determine a temperature representative of the body (22) or the area of ​​interest (25) using a predetermined model, from the average temperature of the electrical circuit.

2. Probe (10) according to claim 1, wherein the variation law has an injective function.

3. Probe (10) according to any one of the preceding claims, wherein the power supply module (52) is configured to adjust the variation law and / or the predetermined model according to at least one characteristic of the electrical circuit and / or the body (22); Preferably, the adjustment should include the implementation of an artificial intelligence technique.

4. Probe (10) according to any one of the preceding claims, wherein the power supply module (52) is further configured to compare said representative temperature with a reference temperature in order to deduce a control setpoint for the heating element (40).

5. Probe (10) according to claim 4, wherein the control setpoint includes a setpoint voltage usable for supplying the electrical circuit.

6. Probe (10) according to claim 5, wherein the power supply module (52) is configured to impose the setpoint voltage on the electrical circuit by applying pulse width modulation.

7. A method for controlling an aerodynamic measuring probe (10) according to any one of the preceding claims, comprising the following steps: - generate (110) electrical resistance measurements of the electrical circuit; - adapt (120) the power supply of the heating element (40) according to the resistance measurements generated.

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