System for measuring at least one chemical component of a fluid for electrochemical power generation systems

Abstract

The present invention relates to a system (100) for measuring at least one chemical component of a fluid for an electrochemical power generation system, wherein the measuring system is A light source (111) that generates a light beam, A double-pass measuring cell (120) includes an inlet opening (121) configured for fluid inflow, an outlet opening configured for fluid outflow, and two port holes positioned on the fluid path, wherein the port holes are positioned opposite each other on a principal optical axis traversing the fluid flow and are configured to transmit a light beam. A reflective optical device (130) positioned to reflect a light beam in the direction of the fluid through a port hole, A Raman spectrometer (112) configured to receive a light beam is used to detect a Raman signal emitted by a fluid and to estimate a measurement of at least one chemical component of the fluid from the detected Raman signal. Includes.

Description

【Technical Field】 【0001】 The present invention generally relates to the measurement of fluid concentration, particularly gas concentration. 【0002】 More particularly, the present invention relates to a system for measuring at least one chemical component of a flowing fluid for a fuel cell type or electrolytic cell type electrochemical power generation system. 【0003】 The present invention has found particularly useful applications in the measurement of gases flowing into and / or out of such an electrochemical power generation system. 【Background Art】 【0004】 A fuel cell type electrochemical power generation system makes it possible to generate electrical energy from the oxidation of a fuel. This fuel is, for example, hydrogen. As a result, electricity is generated from hydrogen. 【0005】 Conversely, an electrolytic cell type electrochemical power generation system makes it possible to generate chemical components from electrical energy. For example, an electrochemical power generation system including an electrolytic cell based on a water electrolysis field makes it possible to generate hydrogen and oxygen by electrical energy. As a result, hydrogen is generated. 【0006】 It may be interesting to measure the concentrations of different chemical elements flowing into and / or out of an electrochemical power generation system in order to characterize the operating state of such an electrochemical power generation system and thus estimate the performance in real time. 【0007】 Currently, the solution consists of extracting a portion of the gas at the inlet or outlet of the electrochemical power generation system and analyzing the gas, with or without destruction of the extracted sample. 【0008】 This tendency is especially pronounced if the gas is destroyed during analysis, as gas extraction can disrupt the operation of the electrochemical power generation system. If the extracted gas is reinjected into the gas circuit without being destroyed, this can, for example, disrupt the timing of measurements. 【0009】 Furthermore, gas extraction can cause changes in pressure and temperature that destabilize the gas, potentially leading to measurement errors. 【0010】 Finally, while many measurement systems today use infrared light, infrared light is not suitable for fluids containing high concentrations of water vapor. 【0011】 For the purpose of performing measurements in real time, it is also important to be able to obtain a high measurement frequency and, consequently, a good signal-to-noise ratio, in order to shorten the integration time. [Overview of the project] [Means for solving the problem] 【0012】 To improve upon the aforementioned shortcomings of current technology, the present invention proposes a system for measuring fluids flowing into or out of an electrochemical power generation system, which operates in real time without the extraction or interruption of the fluids from the circuits of the electrochemical power generation system. 【0013】 More specifically, according to the present invention, a system is proposed for measuring at least one chemical component of a fluid for an electrochemical power generation system, and the measuring system is A Raman spectrometer measuring apparatus including a light source and a Raman spectrometer including a detection system and a processing system, wherein the light source is configured to generate an excitation light beam, A double-pass measuring cell comprising a fluid conduit having an inlet opening configured for the inflow of a fluid and an outlet opening configured for the outflow of a fluid, wherein the measuring cell comprises a first airtight porthole and a second airtight porthole, the two portholes positioned along the side of the fluid conduit downstream of the inlet opening and upstream of the outlet opening, the two portholes positioned opposite each other on a principal optical axis traversing the fluid conduit, and configured to receive an excitation light beam and transmit a first light beam formed by the scattering and / or simple transmission of the excitation light beam through the fluid in the fluid conduit, The present invention includes at least a partially reflective optical device positioned to receive a first light beam transmitted through two port holes, and configured to reflect the first light beam through the two port holes toward a fluid to form a second light beam formed by scattering and / or double transmission of the excitation light beam through the fluid and the two port holes, The Raman spectrometer is configured to receive a second light beam, the detection system is adapted to detect the Raman signal emitted by the fluid, and the processing system is adapted to estimate the measured value of at least one chemical component of the fluid. 【0014】 Therefore, thanks to the present invention, the Raman spectrometer enables the analysis of a fluid in its flow continuity without deviation or extraction, even when the fluid is present in a double-pass cell. Furthermore, the measurement system allows for direct in-line measurements on the fluid conduit without disturbing the fluid, interrupting the flow, or pressurizing the fluid. 【0015】 Furthermore, the arrangement of opposing port holes within the double-pass cell and the position of the port holes relative to the optical device on the principal optical axis allows the measurement system to occupy a minimal amount of space. 【0016】 Finally, the arrangement of the measurement system and double-pass cells enables not only a good signal-to-noise ratio but also double excitation of the fluid. This noisy signal allows for real-time acquisition frequencies of 0.1 Hz to 100 Hz, for example, 1 Hz. The noisy signal enables highly accurate measurements, which in particular allow for the detection of very small amounts of fluid, such as 100 ppm to 500 ppm of dinitrogen, without fluid recirculation or fluid pressurization. 【0017】 In this embodiment, the measuring cell is connected to a fluid transport conduit at the inlet or outlet of the electrochemical power generation system. 【0018】 For example, the measuring cell is connected to the outlet of an electrolytic cell-type electrochemical power generation system, particularly for hydrogen generation, and the Raman spectrometer is adapted to measure the concentration of at least one of the following chemical components: water as water vapor, dinitrogen, dihydrogen, and dioxygen. 【0019】 As an alternative or complement, the measuring cell is connected to the inlet or outlet of a hydrogen fuel cell type electrochemical power generation system for generating electricity from hydrogen, and the Raman spectrometer is adapted to measure the concentration of at least one chemical component from water, dinitrogen, dihydrogen, and dioxygen. 【0020】 Advantageously, the inlet and outlet openings of the measurement cell are connected to the electrochemical power generation system via conduits for transporting the fluid. 【0021】 Advantageously, the cross-sectional areas of the inlet and outlet openings of the measurement cell are larger than the cross-sectional area of ​​the fluid transport conduit in the electrochemical power generation system. 【0022】 Advantageously, an optical system is positioned between the light source and the first port hole, and the optical system is configured to focus the excitation light beam into a measurement cell between the two port holes. 【0023】 According to certain advantageous aspects, at least a partially reflective optical device is configured to reflect a first light beam and focus it into a measurement cell between two port holes. 【0024】 According to another certain advantageous aspect, the measurement cell includes at least one thermal unit configured to maintain the first port hole and / or the second port hole at a temperature above a threshold temperature. 【0025】 Optionally, the first port hole includes a first glass plate, the second port hole includes a second glass plate, and the first glass plate and the second glass plate are each made of one of the glasses of borosilicate glass, aluminosilicate glass, or alkali aluminosilicate glass. Preferably, the measurement system includes a second measurement cell, the Raman spectroscopy device includes another light source suitable for emitting another excitation light beam, and the detection system is an optical sensor including pixels arranged in a plurality of rows, and is configured to simultaneously detect a Raman signal induced by the light source and a second Raman signal emitted by the flowing fluid when the flowing fluid is excited by another excitation light beam. 【0026】 The present invention also proposes a system for measuring at least one fluid flowing into and / or out of an electrochemical power generation system, and this measurement system operates in real time without extracting or blocking the fluid from the circuit of the electrochemical power generation system. 【0027】 More specifically, according to the present invention, a system for measuring at least one chemical component of a flowing fluid for an electrochemical power generation system including a plurality of fluid inlet conduits and / or outlet conduits is proposed, and the measurement system includes a Raman spectroscopy measurement device including a light source configured to generate an excitation light beam, a Raman spectrometer including a detection system and a processing system, and a beam splitter arranged to receive the excitation light beam and form a plurality of split excitation light beams, A plurality of double-pass measurement cells respectively arranged on a fluid inlet conduit or an outlet conduit of an electrochemical power generation system, each double-pass measurement cell including a fluid conduit having an inlet opening configured to allow a flowing fluid arriving from the fluid inlet conduit or the outlet conduit of the electrochemical power generation system to flow in, and an outlet opening configured to allow the flowing fluid to flow out, each measurement cell including a first airtight port hole and a second airtight port hole, the two port holes of each measurement cell being arranged along the side surface of the fluid conduit downstream of the inlet opening and upstream of the outlet opening, the two port holes of each measurement cell being positioned opposite to each other on a main optical axis transverse to the fluid conduit, and configured to receive an excitation light beam and transmit a first light beam formed by scattering and / or simple transmission of the excitation light beam through the flowing fluid in the fluid conduit, a plurality of double-pass measurement cells At least a partially reflective optical device positioned to receive the first light beam transmitted through the two port holes, the at least a partially reflective optical device being configured to reflect the first light beam through the two port holes towards the flowing fluid to form a second light beam formed by scattering and / or double transmission of the excitation light beam passing through the flowing fluid and the two port holes A Raman spectrometer is configured to receive the second light beam from each double-pass measurement cell, a detection system is adapted to individually detect Raman signals emitted by the flowing fluid of each double-pass measurement cell, and a processing system is adapted to estimate measurement values of at least one chemical component of the flowing fluid in each double-pass measurement cell from the detected Raman signals. 【0028】 Obviously, different features, alternatives, and embodiments of the present invention can be associated with each other according to various combinations as long as they are not contradictory or exclusive to each other. 【0029】 The following description, given as a non-limiting example and related to the accompanying drawings, enables a good understanding of what the present invention consists of and how the present invention can be implemented. [Brief explanation of the drawing] 【0030】 [Figure 1] This is a schematic diagram of a measurement system according to an embodiment of the present invention. [Figure 2] This is a schematic diagram of a part of the measurement system applied to a fuel cell type electrochemical power generation system. [Figure 3] This is a schematic diagram of part of the measurement system. [Figure 4] This is a schematic diagram of part of the measurement system. [Figure 5] This is a schematic diagram of the measurement cell according to this disclosure. [Figure 6] Figure 4 is a schematic cross-sectional view of the measurement cell. [Figure 7] Figure 6 is a schematic diagram of a portion of the measurement cell. [Figure 8] This figure shows an example of a spectrometer calibration function. [Figure 9] This figure shows an example of spectral measurement values ​​obtained by the measurement system. [Figure 10] This figure shows an example of how the Raman signal representing dihydrogen as a function of time changes. [Figure 11] This is a schematic diagram of a system equipped with several measuring cells, for example, used in a fuel cell type electrochemical power generation system. [Modes for carrying out the invention] 【0031】 Figure 1 shows a schematic diagram of a measurement system 100 that enables the measurement of the concentration of chemical components present in a fluid 101. The fluid may be gaseous or liquid. 【0032】 Here, the measurement system 100 includes a Raman spectroscopy measuring device 110, a double-pass measurement system 120, an optical device 130, and an optical system 140. 【0033】 The measurement system is adapted in particular to measure the fluid flow for the electrochemical power generation system 200. The electrochemical power generation system 200 can be used as an electrolytic cell. For example, the electrochemical power generation system 200 is an electrolytic cell used to produce hydrogen. The electrochemical power generation system 200 consumes electricity to produce hydrogen. 【0034】 In another application, the electrochemical power generation system 200 is used to generate electricity. In this case, the electrochemical power generation system consumes fuel, such as hydrogen, to generate electricity. 【0035】 Advantageously, Raman spectrometers are adapted to measure the concentration of at least one chemical component, such as water vapor, dinitrogen, dihydrogen, and dioxygen. 【0036】 Figure 2 shows the measurement system 100 when used in a fuel cell type electrochemical power generation system 200. Figure 2 shows a generator type electrochemical power generation system 200. Air and dihydrogen are injected into the fuel cell inlet. Electricity is generated by combustion. At the outlet, the fluid is transported by two conduits 201, namely, the anode conduit 201 and the cathode conduit 201 of the fuel cell. A double-pass measurement cell 120 is placed on at least one conduit 201 to measure the fluid flowing out of the fuel cell 200. Advantageously, each conduit 201 is fitted with a double-pass measurement cell 120 to simultaneously detect the fluid in the conduit 201 connected to the anode and the conduit 201 connected to the cathode, respectively. 【0037】 Figure 4 shows a portion of the measurement system 100 during use. 【0038】 The Raman spectroscopy apparatus 110 includes an interface casing 115, a light source 111, and a Raman spectrometer 112. 【0039】 Figure 3 shows a schematic representation of the measurement principle. 【0040】 The light source 111 is configured to generate an excitation light beam 116. 【0041】 The interface casing 115 is positioned as close as possible to the measurement cell 120. The interface casing 115 provides a measurement interface with the measurement cell. 【0042】 Preferably, the light source 111 is located outside the interface casing 115, and the excitation light beam 116 is transported to the interface casing through the optical fiber cable FO.E. The excitation light beam 116 is transmitted to the measurement cell 120 via the interface casing 115. 【0043】 As an alternative, the light source 111 is positioned within the interface casing 115 of the Raman spectroscopy measuring device 110. 【0044】 Advantageously, as shown in Figure 4, the double-pass measurement cell 120, optical device 130, optical system 140, and interface casing 115 are integrated, for example, on a plate forming an optical-mechanical support, and form a Raman probe 150 connected to the light source 111 and the Raman spectrometer 112 by optical fibers. Thus, a single light source 111 and a single Raman spectrometer 112 can be connected to a plurality of local Raman probes 150 located at the inlet and / or outlet of the electrochemical power generation system 200. 【0045】 The light source 111 is preferably a high-intensity laser. Here, the light source 111 is, for example, a laser with an output of 1.5 W that emits a monochromatic light beam having a wavelength of 532 nm. The light source is high-power to obtain a Raman signal of sufficient intensity to enable integration times suitable for real-time monitoring, for example, at a speed of about 1 Hz. 【0046】 Alternatively, the excitation beam can be generated from any light source adapted to produce part or all of the spectrum. 【0047】 The measuring cell 120 includes a fluid conduit 129 having an inlet opening 121 and an outlet opening 122, and a first airtight port hole 123 and a second airtight port hole 124. 【0048】 The inlet opening 121 is connected to the first fluid transport conduit 201 and is configured to allow the fluid 101 to flow in. 【0049】 The outlet opening 122 is connected to the second fluid transport conduit 202 and configured to allow the fluid 101 to flow out. The fluid conduit 129 guides the fluid 101 flowing in through the inlet opening 121 toward the outlet opening 122. 【0050】 To prevent any change in the pressure or flow rate of the fluid 101, the cross-sections of the inlet opening 121, the outlet opening 122, and the fluid conduit 129 are each larger than or equal to the cross-sections of the fluid transport conduits 201 and 202. 【0051】 For example, in this case, the transport conduits 201 and 202 and the measuring cell 120 have a circular cross-section, and the inner diameter of the cross-section of the measuring cell 120 and the two inlet openings 121 and outlet opening 122 is 16 mm, which is the same as the inner diameter of the two transport conduits 201 and 202. The fluid pressure in the measuring cell is the same as the fluid pressure in the conduits 201 and 202. The total fluid pressure in the conduits 201 and 202 is, for example, 2 bar. 【0052】 The two portholes 123 and 124 are positioned along the side of the fluid conduit 129, downstream of the inlet opening 121 and upstream of the outlet opening 122. The two portholes 123 and 124 are positioned opposite each other. For example, the fluid conduit 129 has a circular cross-section, and the two portholes 123 and 124 are positioned diametrically opposite each other. In another example, the fluid conduit 129 has a square or rectangular cross-section, and the two portholes 123 and 124 are positioned on two opposing faces of the fluid conduit 129. In this way, the fluid 101 passes between the two portholes 123 and 124. 【0053】 The measurement cell 120 is positioned such that two port holes 123 and 124 are located on the principal optical axis OA that crosses the fluid. 【0054】 The two port holes 123 and 124 are configured to transmit the excitation light beam 116. For example, the excitation light beam propagates along the principal illumination axis, which is aligned with the principal optical axis. 【0055】 The two port holes 123 and 124 are configured to allow the first light beam 117, formed by scattering and / or simple transmission of the excitation light beam, to pass through the fluid 101. 【0056】 In other words, the measuring cell 120 is integrated with the fluid transport conduits 201 and 202, and moreover, thanks to the port hole, it accommodates the fluid 101 that is ready to be measured without the need to extract or deviate the fluid 101 from the flow conduits 201 and 202. 【0057】 The measurement cell 120 shown in Figures 4 to 6 allows for the analysis of the fluid 101 without changes in pressure, humidity, or temperature. Therefore, the measured values ​​are as close as possible to the actual state of the fluid 101 at the fuel cell inlet or outlet. The measurement cell 120 has a very small footprint on the flow conduits 201 and 202. 【0058】 In the first embodiment, the inlet opening of the measuring cell 120 is connected to a fluid transport conduit at the outlet of the electrochemical power generation system 200. 【0059】 In the second embodiment, the outlet opening is connected to a fluid transport conduit at the inlet of the electrochemical power generation system 200. 【0060】 Therefore, the measuring cell can be connected to the outlet or inlet of the electrochemical power generation system 200, for example, to examine the fluid flowing into or out of the electrochemical power generation system 200. 【0061】 The first porthole 123 includes a first glass plate 125, and the second porthole 124 includes a second glass plate 126. 【0062】 The glass plates 125 and 126 are preferably made from borosilicate glass, aluminosilicate glass, or alkali aluminosilicate glass. For example, the glass plates 125 and 126 are here made from BK glass or Gorilla Glass. Preferably, the glass plates 125 and 126 do not have a surface coating on the side that comes into contact with the fluid 101. The composition and arrangement of the glass plates 125 and 126 are such that gas release or contamination of the fluid due to the interaction between the fluid and such surface coatings, which tends to contaminate the measurement, can be prevented. 【0063】 The portholes 123 and 124 are airtight due to the use of gaskets. The measuring cell 120 includes, for example, two gaskets 127 and 128, namely, a first gasket 127 positioned between a first glass plate 125 and a fluid conduit 129, and a second gasket 128 between a second glass plate 126 and a fluid conduit 129. 【0064】 Similar to the materials of the glass plates 125 and 126, the materials of the gaskets 127 and 128 must not contaminate the measurements. For this purpose, the joints 127 and 128 are manufactured using inert components. The gaskets 127 and 128 are made here from a fluoroelastomer material (commonly known as FKM or viton). 【0065】 The glass plates 125 and 126 form low-temperature points. These low-temperature points in the passage of the fluid 101 cause condensation, especially if the fluid 101 contains water or water vapor. 【0066】 The presence of condensation on port holes 123 and 124 can lead to a deterioration in measurement quality, particularly as a result of reduced signal intensity or increased optical aberrations. 【0067】 According to a particular embodiment shown in Figure 7, the measuring cell 120 includes at least one thermal unit. The thermal unit is configured to maintain a temperature above a threshold temperature for a first port hole and / or a second port hole. Preferably, the measuring cell 120 includes two thermal units 131 configured to maintain a temperature above a threshold temperature for two port holes 123, 124. The thermal units are powered by an electrical cable 132. 【0068】 The threshold temperature is defined as a function of the temperature of the fluid 101. For example, if the fluid 101 is at a temperature of approximately 60°C, the threshold temperature is approximately 70°C. The thermal unit makes it possible to prevent condensation from occurring on the port holes 123 and 124. 【0069】 The optical system 140 is positioned in the path of the excitation light beam 116 between the light source 111 and the first port hole 123. The optical system 140 is configured to focus the excitation light beam 116 into the fluid 101 between the two port holes 123 and 124 of the measurement cell 120. For example, the optical system 140 is, for example, a lens or an objective lens. The second port hole 124 transmits the first light beam 117, formed by the scattering and / or simple transmission of the excitation light beam 116 through the fluid 101, toward the optical device 130. 【0070】 The optical device 130 is at least partially reflective. Preferably, the optical device 130 is a concave mirror. The optical device 130 is, for example, a spherical mirror positioned such that its center of curvature is located on the principal optical axis OA, midway between the two glass plates 123 and 124. 【0071】 The optical device 130 is positioned to receive the first light beam 117 transmitted through the second port hole 124. The reflective optical device 130 is positioned outside the measurement cell 120. This arrangement makes it possible to avoid any interaction between the fluid 101 and the reflective coating of the optical device 130, such as metal, and to prevent any contamination of the fluid 101. 【0072】 The optical device 130 is configured to reflect the first light beam 117 to form a reflected light beam 118 directed toward the fluid 101 passing through the second port hole 124. The optical device 130 is configured to focus the reflected light beam 118 into a measuring cell between the two port holes. For example, the optical device 130 preferably includes a spherical mirror positioned midway between the two port holes 123, 124 to focus the reflected light beam 118 toward the fluid 101. 【0073】 A second light beam 119 is obtained after passing through the fluid 101 and the first port hole 123, which is formed by the scattering and / or double transmission of the excitation light beam 116 through the fluid 101 and the port holes 123 and 124. The second light beam 119 propagates toward the optical system 140, which allows the second light beam 119 to be focused. 【0074】 The association between the double-pass measurement cell 120 and the reflective optical device 130 enables double excitation of the fluid 101. In fact, the excitation beam that has passed through the measurement cell 120 is focused again onto the fluid 101, effectively doubling the excitation. This optical configuration also has the advantage of doubling the collection angle by collecting not only a portion of the Raman signal emitted toward the Raman spectrometer, but also a portion of the Raman signal emitted toward the optical device 130, then reflected, and sent back toward the Raman spectrometer 110. 【0075】 The term "double pass" refers to the round trip of the light beam in the measurement cell 120. However, the fluid 101 passes through the measurement cell 120 only once in the flow direction without interruption of flow. 【0076】 The Raman spectrometer 112 includes a detection system 113 and a processing system 114. The Raman spectrometer 112 is configured to receive a second light beam 119 containing a Raman signal emitted by the fluid 101. 【0077】 Preferably, the Raman spectrometer 112 is located outside the interface casing 115 that forms the local probe and is connected to this local probe via an optical fiber cable FO.S, as shown in Figures 1 and 4. 【0078】 As an alternative, the Raman spectrometer 112 is integrated into the interface casing 115. 【0079】 To avoid airborne contamination during measurement, the optical device 130 and optical system 140 are positioned as close as possible to the measurement cell 120 in order to shorten the optical path of the light beam. 【0080】 For similar reasons, the external casing 115 for collecting signals is positioned as close as possible to the optical system 140. 【0081】 The Raman spectrometer 112 is adapted to detect the Raman signal emitted by the fluid 101 in the second light beam 119. The Raman signal is emitted thanks in particular to the excitation of the fluid 101 by the excitation light beam 116 and the reflected light beam 118. 【0082】 The Raman spectrometer 112 generally includes a diffraction grating and a photosensor 113. 【0083】 Diffraction gratings are formed, for example, by straight lines, parallel lines, and equally spaced lines. A diffraction grating is a reflection network positioned to receive and reflect a light beam incident on a Raman spectrometer, for example, and to form a light beam that is diffracted to different wavelengths of the spectrum. 【0084】 The diffracted light beam is generally focused onto the light sensor 113 using a diffraction grating or an optical focusing system such as a mirror or lens. 【0085】 The light sensor 113 includes, for example, pixels arranged along one or more rows. 【0086】 The rows of pixels are generally oriented in the spectral diffraction direction of the diffracted light beam image. Preferably, each row contains an equal number of pixels arranged in columns such that the pixels form a matrix on the photosensor. 【0087】 Alternatively, the Raman spectrometer 110 includes a second light source adapted to emit a second excitation light beam, and the photosensor is configured to simultaneously detect the Raman signal 119 induced by the light source and the second Raman signal emitted by the fluid 101 when the fluid 101 is excited by the second light source. 【0088】 The processing system 114 is adapted to estimate a measurement of at least one chemical component of the fluid 101 from the Raman signal detected by the detection system 113. 【0089】 The processing system 114 enables reading the light sensor and estimating at least one spectrum from it. At least one spectrum can be obtained, for example, by summing a portion of the pixels in the same column. 【0090】 Preferably, the Raman spectrometer allows for the acquisition of one spectrum per second to monitor the fluid 101 in real time. 【0091】 Figure 9 shows an example of a Raman spectrum measured in this way. In the Raman spectrum of Figure 9, the intensity I of the measured signal is expressed as a function of the Raman offset Δω (in cm⁻¹ units). The measured signal has a peak at approximately 2300 cm⁻¹ and corresponds to dinitrogen. The measured signal has another peak at approximately 4100 cm⁻¹ and corresponds to dihydrogen. 【0092】 The intensity of the measured Raman signal is determined by the concentration of the elements present, the pressure value, and the power of the excitation beam. The processing system 114 is configured to calculate the concentration of a desired chemical component using the measured signal and a calibration function t0. The calibration function allows for the establishment of a function between the measured Raman signal of a chemical component and the concentration of that chemical component. 【0093】 Figure 8 shows the calibration function for converting the measured signal intensity to dihydrogen concentration. 【0094】 The calibration function is determined, for example, using measurements of a standard fluid of a given concentration. 【0095】 For example, in Figure 10, a fluid containing dihydrogen at a predetermined and variable concentration is measured by the measurement system 100. The measured signal includes several plateaus, each corresponding to a different concentration. The dihydrogen concentration corresponding to the plateau between instantaneous t=0 and instantaneous t=approximately 308s is equal to 0%. The dihydrogen concentration corresponding to the plateau between instantaneous t=approximately 308s and instantaneous t=approximately 400s is equal to 2%. The dihydrogen concentration corresponding to the plateau between instantaneous t=approximately 400s and instantaneous t=approximately 520s is equal to 5%. The dihydrogen concentration corresponding to the plateau between instantaneous t=approximately 520s and instantaneous t=approximately 610s is equal to 10%. The dihydrogen concentration corresponding to the plateau between instantaneous t=approximately 610s and instantaneous t=approximately 710s is equal to 20%. The dihydrogen concentration corresponding to the plateau between instantaneous t=approximately 710s and instantaneous t=approximately 810s is equal to 60%. The dihydrogen concentration corresponding to the plateau between instantaneous time t at approximately 810 s and instantaneous time t at approximately 910 s is equal to 80%. The dihydrogen concentration corresponding to the plateau between instantaneous time t at approximately 910 s and instantaneous time t at approximately 1000 s is equal to 100%. Therefore, the curve represents the intensity of the Raman signal for fluids containing dihydrogen at concentrations from 0 to 100%. 【0096】 This curve makes it possible to establish the calibration function shown in Figure 8. 【0097】 This curve also allows for the establishment of measurement accuracy. In the example shown in Figure 10, a measurement accuracy of approximately 5% is observed. The measurement system 100 provides an accuracy of up to 0.2%. 【0098】 The calibration function can also be used to account for the aging degradation of the measurement system 100, such as a decrease in the intensity of the light source 111 or a decrease in the transmittance of the components used (port holes 123, 124, optical devices 130, and optical system 140). Generally, the calibration function is updated at regular intervals or as needed. 【0099】 The measurement system 100 also enables the detection of contaminating chemical components. For example, the processing system 114 is configured to detect signals in the spectrum that do not correspond to the chemical elements expected in the fluid 101. 【0100】 For example, the Raman signal intensities corresponding to dihydrogen and dinitrogen are measured simultaneously as a function of time. By monitoring the change in the Raman signal over time, it becomes possible to monitor and record various events occurring in the fuel cell type electrochemical power generation system 200, particularly in the hydrogen fuel cell generating electricity. These events may include an increase in load, fluctuations in fluid supply, or unloading of the electrochemical power generation system 200. 【0101】 Figure 11 shows a multipoint measurement system based on the use of multiple measurement cells. Such a measurement system makes it possible to simultaneously measure the chemical composition of at least one fluid at several inlet and / or outlet points of an electrochemical power generation system that includes multiple fluid inlet and / or outlet conduits 201. The multipoint measurement system is particularly applicable to fuel cells or electrolytic cells. For example, a fuel cell includes two fluid inlet conduits 201, one inlet conduit 201 fitted for air injection and the other inlet conduit 201 fitted for dihydrogen injection. The fuel cell also includes two fluid outlet conduits 201, namely one outlet conduit 201 on the anode side of the fuel cell and the other outlet conduit 201 on the cathode side. 【0102】 To that end, the measurement system includes a plurality of double-pass measurement cells 1201, 1202, 1203, 1204, respectively, located on the fluid inlet or outlet conduit 201 of the electrochemical power generation system. The plurality of measurement cells includes two, three, four, or five or more measurement cells. In an embodiment, the measurement system includes a measurement cell 1201 on the outlet conduit 201 and another measurement cell 1202 on another outlet conduit 201. In an embodiment, the measurement system includes a measurement cell 1201 on the outlet conduit 201 and another measurement cell 1203 on the dihydrogen inlet conduit 201. In another example, the measurement system includes a measurement cell 1201 on the outlet conduit 201 and another measurement cell 1203 on the oxygen inlet conduit 201. In another example, the measurement system includes a measurement cell 1203 on the dihydrogen inlet conduit 201 and another measurement cell 1204 on the oxygen inlet conduit 201. In yet another example, the measurement system includes a measurement cell 1203 on a dihydrogen inlet conduit 201, another measurement cell 1204 on an oxygen inlet conduit 201, a measurement cell 1201 on an outlet conduit 201, and another measurement cell 1202 on another outlet conduit 201. The controller enables the activation of measurements in multiple measurement cells among those installed on the conduits. 【0103】 The multipoint measurement system also includes a Raman spectrometer 110, which includes a light source 111 and a Raman spectrometer 112, which includes a detection system 113 and a processing system 114. The light source 111 is configured to generate an excitation light beam 116. Advantageously, a beam splitter is positioned to receive the excitation light beam 116 and form multiple split excitation light beams. For example, a beam splitter is used. Each split excitation light beam is guided, for example, through an optical fiber to one of the multiple measurement cells. This configuration makes it possible to use the same light source 111 for measuring multiple measurement cells, all operating at the same light source wavelength. Alternatively, several light sources are used, each generating an excitation light beam that is guided towards the measurement cell. 【0104】 Each measurement cell 1201, 1202, 1203, and 1204 is configured on a specific inlet or outlet conduit of the electrochemical power generation system, as described above, for example in relation to Figure 3. Each measurement cell 1201, 1202, 1203, and 1204 is adapted to receive a split excitation light beam and transmit a first light beam, formed by the scattering and / or simple transmission of the split excitation light beam, through the fluid 101 in the fluid conduit under consideration. As described above, at least a partially reflective optical device 130 of each fluid cell is positioned to receive the first light beam transmitted through two port holes and is configured to reflect the first light beam toward the fluid through two port holes 123 and 124 to form a second light beam, formed by the scattering and / or double transmission of the excitation light beam through the fluid 101 and the two port holes 123 and 124. 【0105】 The Raman spectrometer 112 is configured to individually receive second light beams from each double-pass measurement cell 1201, 1202, 1203, and 1204, for example, via optical fibers. Advantageously, the optical fibers carrying the second light beams from each measurement cell 1201, 1202, 1203, and 1204 are arranged linearly along the elongated direction of the entrance slot of the Raman spectrometer 112. The detection system preferably includes an imaging detector adapted to individually detect the Raman signals corresponding to each second light beam arriving from each measurement cell 1201, 1202, 1203, and 1204. Thus, the detection system allows for the individual detection of Raman signals emitted by the fluid flow of each double-pass measurement cell in different regions of the imaging detector. Advantageously, detection of different Raman signals arriving from different measurement cells is performed simultaneously. The processing system is adapted to estimate the measured values ​​of at least one chemical component of the fluid in each double-pass measurement cell 1201, 1202, 1203, and 1204 from the detected Raman signals. Such a multi-point measurement system makes it possible to measure the chemical composition of the fluid at several inlet and / or outlet points of the electrochemical power generation system 200 at low cost. Particularly advantageous is that the system includes as many measurement cells as there are fluid inlet and outlet conduits, thereby enabling real-time, non-intrusive, and simultaneous measurement of all fluid inlets and outlets of the electrochemical power generation system 200. Such a system provides information regarding the operation of the electrochemical power generation system 200. 【0106】 In particular, in a fuel cell, it is especially advantageous to have a measurement cell 1203 on the anode inlet conduit, a measurement cell 1204 on the cathode inlet conduit, a measurement cell 1201 on the anode outlet conduit, and a measurement cell 120 on the cathode outlet conduit. Measurement cells 1201 and 1203 on the inlet and outlet anodes can be used to monitor the chemical composition of the fluid, particularly dihydrogen, dinitrogen, water (H2O), carbon dioxide (CO2), and carbon monoxide (CO). Measurement cells 1202 and 1204 on the inlet and outlet cathodes can be used to monitor the chemical composition of the fluid, particularly dihydrogen, dinitrogen, and water (H2O). These measurements, performed simultaneously in real time, enable evaluation of fuel cell efficiency, implementation of fuel cell stress measurements, modeling or simulation, or improvement of the fuel cell. 【0107】 A multi-point measurement system can also be applied to simultaneously monitor the fluid inlet and outlet of an electrolytic cell in real time and non-intrusively. 【0108】 The present invention is by no means limited to the embodiments described and illustrated, but those skilled in the art will know how to apply any modifications of the present invention.

Claims

[Claim 1] A measuring system (100) for measuring at least one chemical component of a fluid (101) for an electrochemical power generation system (200), wherein the measuring system is A Raman spectrometer (110) includes a light source (111) and a Raman spectrometer (112) including a detection system (113) and a processing system (114), wherein the light source (111) is configured to generate an excitation light beam (116), A double-pass measuring cell (120) includes a fluid conduit (129) having an inlet opening (121) configured to allow the fluid (101) to flow in and an outlet opening (122) configured to allow the fluid (101) to flow out, wherein the measuring cell (120) includes a first airtight porthole (123) and a second airtight porthole (124), the two portholes (123, 124) being downstream of the inlet opening (121) and A double-pass measurement cell (120) is positioned upstream of the outlet opening (122) along the side surface of the fluid conduit (129), and the two port holes (123, 124) are positioned opposite each other on the principal optical axis traversing the fluid conduit, and are configured to receive the excitation light beam and transmit a first light beam formed by the scattering and / or simple transmission of the excitation light beam through the fluid (101) in the fluid conduit, The optical device (130) is positioned to receive the first light beam transmitted through the two port holes (123, 124), and is configured to reflect the first light beam through the two port holes (123, 124) toward the fluid (101) to form a second light beam (119) formed by scattering and / or double transmission of the excitation light beam through the fluid (101) and the two port holes (123, 124), the optical device (130) being at least partially reflective, Measurement system (100), wherein the Raman spectrometer (112) is configured to receive the second light beam (119), the detection system (113) is adapted to detect the Raman signal emitted by the fluid (101), and the processing system (114) is adapted to estimate a measured value of at least one chemical component of the fluid (101). [Claim 2] The measurement system (100) according to claim 1, wherein the measurement cell (120) is connected to the outlet of an electrolytic cell type electrochemical power generation system (200), particularly for hydrogen generation, and the Raman spectrometer (110) is adapted to measure the concentration of at least one chemical component among water, dinitrogen, dihydrogen, and dioxygen. [Claim 3] The measurement system (100) according to claim 1, wherein the outlet opening (122) of the measurement cell (120) is connected to the inlet or outlet of a hydrogen fuel cell type electrochemical power generation system (200), and the Raman spectrometer (110) is adapted to measure the concentration of at least one chemical component among water, dinitrogen, dihydrogen, and dioxygen. [Claim 4] The measurement system (100) according to any one of claims 1 to 3, wherein the inlet opening (121) or outlet opening (122) of the measurement cell (120) is connected to the electrochemical power generation system (200) via a fluid transport conduit (201; 202). [Claim 5] The measurement system (100) according to claim 4, wherein the cross-sections of the inlet opening (121) and the outlet opening (122) of the measurement cell (120) are each larger than or equal to the cross-sections of the fluid transport conduits (201, 202) of the electrochemical power generation system (200). [Claim 6] The measurement system (100) according to any one of claims 1 to 5, comprising an optical system (140) disposed between the light source (111) and the first port hole (123), wherein the optical system (140) is configured to focus the excitation light beam into the measurement cell (120) between the two port holes (123, 124). [Claim 7] The measurement system (100) according to any one of claims 1 to 6, wherein the at least partially reflective optical device (130) is configured to reflect the first light beam and focus it into the measurement cell (120) between the two port holes (123, 124). [Claim 8] The measurement system (100) according to any one of claims 1 to 7, wherein the measurement cell (120) includes at least one thermal unit (131) configured to maintain the first port hole (123) and / or the second port hole (124) at a temperature above a threshold temperature. [Claim 9] The measuring system (100) according to any one of claims 1 to 8, wherein the first porthole (123) includes a first glass plate, and the second porthole (124) includes a second glass plate, and the first glass plate and the second glass plate are each made from one of the following types of glass: borosilicate glass or alkali aluminosilicate glass. [Claim 10] A measurement system (100) according to any one of claims 1 to 9, comprising a second measurement cell, wherein the Raman spectrometer (110) comprises a second light source adapted to emit a second excitation light beam, and the detection system (113) comprises a photosensor comprising pixels arranged in multiple rows, configured to simultaneously detect the Raman signal induced by the light source (111) and a second Raman signal emitted by the fluid (101) when the fluid (101) is excited by the second excitation light beam. [Claim 11] A measuring system for measuring at least one chemical component of a fluid (101) for an electrochemical power generation system (200) including a plurality of fluid inlet and / or outlet conduits (201), wherein the measuring system is A Raman spectrometer (110) includes a light source (111) configured to generate an excitation light beam (116), a Raman spectrometer (112) including a detection system (113) and a processing system (114), and a beam splitter arranged to receive the excitation light beam (116) and form a plurality of divided excitation light beams. A plurality of double-pass measuring cells (1201, 1202, 1203, 1204) are respectively arranged on the fluid inlet conduit or outlet conduit (201) of the electrochemical power generation system, each double-pass measuring cell (1201, 1202, 1203, 1204) includes a fluid conduit (129) having an inlet opening (121) configured to allow the flowing fluid arriving from the fluid inlet conduit or outlet conduit (201) of the electrochemical power generation system (200) to flow in, and an outlet opening (202) configured to allow the flowing fluid to flow out, and each measuring cell (1201, 1202, 1203, 1204) includes a first airtight port hole (123) and a second airtight port hole (124). The two port holes (123, 124) of each measurement cell (1201, 1202, 1203, 1204) are positioned along the side surface of the fluid conduit downstream of the inlet opening and upstream of the outlet opening, and the two port holes (123, 124) of each measurement cell (1201, 1202, 1203, 1204) are positioned opposite each other on the principal optical axis traversing the fluid conduit, and are configured to receive the divided excitation light beam and transmit the first light beam formed by the scattering and / or simple transmission of the excitation light beam through the fluid (101) in the fluid conduit, comprising a plurality of double-pass measurement cells (1201, 1202, 1203, 1204), The optical device (130) is at least partially reflective and positioned to receive the first light beam transmitted through the two port holes, and is configured to reflect the first light beam through the two port holes (123, 124) toward the fluid to form a second light beam formed by scattering and / or double transmission of the excitation light beam through the fluid (101) and the two port holes (123, 124), the optical device (130) being at least partially reflective, A measurement system comprising a Raman spectrometer (112) configured to individually receive the second light beam from each double-pass measurement cell (1201, 1202, 1203, 1204), a detection system adapted to individually detect the Raman signals emitted by the fluid in each double-pass measurement cell, and a processing system adapted to estimate a measurement of at least one chemical component of the fluid in each double-pass measurement cell (1201, 1202, 1203, 1204) from the detected Raman signals.

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