Method for controlling a flow rate measurement of a tank connected to a pressurized fluid distribution station.

Abstract

Method for controlling a flow rate measurement for filling a tank (10) connected to a pressurized fluid distribution station (100), the station (100) comprising a fluid source (2), a distributor (4) connected to the source (2) and a supply hose (6) connected to the distributor (4) and intended to be coupled to the tank (10) to be filled, the distributor (4) being equipped with a pressure sensor, a temperature sensor, and a flow meter, the method comprising the following operations: - measurement (S1) of a flow rate value (t) at a given time (t) using the flow meter installed at the distributor (4), - estimation (S2) of a flow rate value (t) at the distributor (4) at time (t), the estimation being based on the following parameters: a first value of the fluid pressure (t) at time (t) measured by the pressure sensor installed at the distributor,a second data point of the fluid temperature () at time (t) measured by the temperature sensor installed at the distributor (4), a third data point of the fluid pressure () at time (t) in the tank (10) to be filled, the third data point being measured using a pressure sensor located in the tank (10) or calculated from a physical model, a fourth predetermined data point of the hydraulic pressure loss coefficient () due to the supply hose (6), - comparison (S3) between the measured data () and the estimated data () of the flow rate at time (t), - generation (S4) of a signal representative of the reliability of the estimated data () of the flow rate. Figure of the abstract: Figure 2,

Description

Title of the invention: Method for controlling a measurement of the filling flow rate of a tank connected to a distribution station of a pressurized fluid.

[0001] The invention relates to a method for controlling a flow rate measurement of a tank connected to a pressurized fluid dispensing station. The fluid in question may be gaseous hydrogen. The tank in question may be that of a fuel cell vehicle (FCV) running on hydrogen.

[0002] In a distribution station, it is necessary to know the flow rate of the delivered fluid, particularly for billing purposes, but also for safety reasons during filling operations. Knowing the flow rate of the delivered fluid also makes it possible to estimate the volume of the tank, and thus choose the filling protocol (SAE J2601) best suited to the tank volume.

[0003] To access a data of the flow rate of fluid transferred to a reservoir, the distribution station includes a flow meter.

[0004] In the event of malfunctions, the flow meter provides erroneous flow data. Consequently, the estimation of the tank volume, which is necessary to determine the tank category, will be inaccurate. Furthermore, the choice of the filling protocol will be biased due to the lack of accurate information on the tank category.

[0005] By way of illustration, an overestimated mass flow rate will lead to an overestimation of the tank volume. Filling will then be carried out according to a protocol designed for a larger tank.

[0006] Similarly, in the event of erroneous data on the mass flow rate, a safety barrier, intended to prevent overfilling or excessive heating of the tank to be filled, can no longer reliably perform its function.

[0007] To check the reliability of the flow measurements provided by a flowmeter, one solution could consist, on the one hand, of weighing the tank before and after filling, and then recording the difference in the masses obtained; and on the other hand, of integrating over the duration of the filling the flow measured by the flowmeter.

[0008] Assuming that the difference between the masses obtained by weighing the tank before and after filling is accurate, a discrepancy between the result thus obtained and the result obtained by integrating the flow rate measured over the filling time would then be an indication of an error in the measurement of the flow rate given by the flow meter.

[0009] However, such a control solution introduces several technical difficulties when weighing the tank before and after filling, and requires a relatively long time to carry out this weighing.

[0010] Also, the control solution described above is not feasible on distribution stations.

[0011] It therefore appears necessary to develop a method for controlling the measurement of the filling flow rate of a tank supplied by a distribution station, which is simple to implement and does not require additional means on the station.

[0012] To this end, the invention proposes a method for controlling a measurement of the filling flow rate of a tank connected to a distribution station of a pressurized fluid.

[0013] The station comprises a fluid source, a distributor connected to the source, and a supply hose connected to the distributor and intended to be coupled to the tank to be filled. In particular, the distributor is equipped with a pressure sensor, a temperature sensor, and a flow meter.

[0014] The method according to the invention comprises the following operations: - measurement of flow rate data at a given time t using the flow meter installed at the level

[0015] from the distributor, - estimation of a flow rate data at the distributor at time t, the estimation being based on the following parameters: a first data point of the fluid pressure at time t measured by the pressure sensor installed at the distributor, a second data point of the fluid temperature at time t measured by the temperature sensor installed at the distributor, a third data point of the fluid pressure in the tank to be filled, the third data point being measured using a pressure sensor placed in the tank or calculated from a physical model, a fourth predetermined data point of the hydraulic pressure loss coefficient due to the supply hose, - comparison between the measured data and the estimated data of the flow rate at time t. Such a comparison makes it possible to verify the reliability of the measured flow rate data. Embodiments of the invention may include one or more of the following features: - The estimated filling flow rate at time t is obtained from a predetermined calculation formula clu' is a function of a ratio between the predetermined pressure loss coefficient kv and the square root of the temperature measured at the distributor, the calculation formula comprising: - a first sub-formula allowing estimation of the flow rate for a pressure pM in the distributor less than twice the pressure Ptank(t) in the reservoir, the first sub-formula being a function of the square root of the difference between the pressure in the distributor and the pressure p^ in the reservoir, and - a second sub-formula allowing estimation of the flow rate for a given pressure pdh^t) in the distributor greater than twice the pressure ^0 in the reservoir, the second sub-formula being given by a linear function by in relation to the pressure pdis^t} in the distributor, - the first and second sub-formulas are expressed respectively in the following manner:

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022] 2, for Pdisp < 2Pta„k J n ( 'For disp >-Ptank Ûlgas2 ( t ) — Æ t p- .Pdispl 1I y \ / with: Pdisp(t) ct Pf x-ÛO ' resPectivement 'a pressure in the distributor and the pressure in the reservoir, expressed in [Pa]; kv: the coefficient of hydraulic pressure losses due to the supply hose and the receiving conduit specific to the tank to be filled, expressed in ["L]; h 1 A: a coefficient depending on the density Pgas of the fluid at 0°C and 1.0135 bar (expressed in [^j], the density Pcàr of Pair at 0°C and 1.0135 bar (expressed in [*£]), the compressibility factor ( / ) of the fluid in the distributor (expressed ! ^3' (USp\ / (unitless) - the coefficient (A) depends on a ratio between, on the one hand, the product of the air density Pair and the fluid density Pgas, and on the other hand, the compressibility factor Zp^t) of the fluid in the distributor, the expression of the coefficient (A) being given by: A = 32 -the process includes at least one stop phase [T1^ ^c] of the filling, the pressure P tank in the reservoir being deduced from the pressure Pdisp in the distributor measured immediately before the stop phase [TA, T(:\ of the filling and / or after the stop phase [7\, 7c] of the filling, - the at least one stop phase [7^, Pc] of the filling comprises two time intervals [7'v TB], [Tb, Tc| in each of which the pressure Pdisp in the distributor varies and exhibits a maximum Pdisp max and a minimum Pdisp min, the estimation of the data tn^s_est of the filling flow rate being carried out on any one of the said intervals [rA, TB],[TB, Tc], - the estimation of the data w^as is the flow rate over the first time interval [TA, TB\ is performed from a first data point P disp 1 of the pressure Pdisp in the distributor at a first instant and from a first data point Pimk_\ of the pressure P tank in the reservoir at the first instant *1, the first data point Ptank_i of the pressure P tank in the reservoir at the first instant b being deduced from a second data point Ptanki of the pressure P tank in the reservoir at a second instant ^2 and from a second data point Pdisp_2 of the pressure Pdisp in the distributor at the second instant ^2, the first instant being prior to the second instant ^2, the second instant ^2 coinciding with the second boundary of the first interval Pb] and / or - The estimation of the data nigas_est of the flow rate over the second time interval [TB' Pcl is carried out from a fourth data P disp Jt of the pressure P disp in the distributor at a fourth instant ^4, and from a fourth data P tank a of the pressure Ptank in the reservoir at the fourth instant / 4, the fourth data Ptankj\ of the pressure P tank in the reservoir being deduced from a third data Ptank_3 of the pressure P tank in the reservoir at a third instant h, and from a third data Pdisp-3 of the pressure Pdisp in the distributor at the third instant P. the fourth instant / 4 being subsequent to the third instant h, the third instant ^3 coinciding with the first bound of the second interval [TB, Te], - the first Pdispj value of the fluid pressure Pdisp in the distributor at the first instant is equal to the maximum Pdisp mari value of the pressure measured by the pressure sensor over the first interval | v T - the fourth data Pdisp_^ of the pressure Pdisp of the fluid in the distributor at the fourth instant is equal to the maximum value Pdisp_max2 of the pressure measured by the pressure sensor on the second interval [T1g, Tc] - the second data point Pdispj, the pressure Pdisp of the fluid in the distributor at the second instant / 2, is equal to the minimum value Pdisp min measured by the pressure sensor over the first interval [7^, Tg], respectively - the third data Pdisp_3 of the pressure P disp of the fluid in the distributor at the third instant P is equal to the minimum value Pdisp min measured by the pressure sensor on the second interval [TB, Tc], - the first data point P / «nk_\ of the pressure Ptank in the reservoir at the first instant ?icst equals the second data point Pdisp_2 of the pressure Pdisp of the fluid in the distributor at the second instant ^2, - the fourth data point Pumkj, of the pressure P tank in the reservoir at the fourth instant / 4 is equal to the third data point Pjîsp_3 of the pressure Pdisp in the distributor at the third instant ^3, - the process including a step of comparing: i) the ingas_mes data measured by the flowmeter at the second instant / 2, respectively at the third instant ^3, with a first predefined threshold value ei; and / or ii) the difference between the second data point P disp J and the first data point Pdisp_h, respectively between the fourth data point Pdisp_A and the third data point Pdispj^, of the pressure P disp of the fluid in the distributor with a second predefined threshold value - Equality between the first data point Ptankj of the pressure P tank in the reservoir at the first instant and the second data point Pdixpi of the pressure Pdisp in the distributor at the second instant ^2, respectively between the fourth data point Ptank i of the pressure P tank in the reservoir at the fourth instant ^4 and the third data point Pdisp_3 of the pressure Pdisp in the distributor at the third instant / 3 is accepted when one of the following criteria is satisfied: i) the Algas_mes data measured by the flowmeter at the second instant h, respectively at the third instant ^3, is less than the first predefined threshold value ei, ii) the difference between the second data Pdisp_2 and the first data Pdisp_h, respectively between the fourth data Pdispl and the third data Pdlspj^ of the pressure Pdisp of the fluid in the distributor is less than the second predefined threshold value £2, - the [rA, Tc] filling stop phase is part of a leak test operation intended to check the tightness of a fluid connection between the supply hose and the tank to be filled, - the pressure loss coefficient kv is the sum of a first component kv} relating to losses due to the supply hose, and a second component kr2 relating to losses due to a receiving conduit fixed to the tank to be filled.

[0023] Other features and advantages will become apparent from the following description, made with reference to the following figures in which:

[0024] [Fig.1] schematically illustrates a reservoir connected to a pressurized fluid distribution station, the station comprising in this order: a source, a pressure and / or flow control valve, a distributor and a supply hose, the distributor being equipped with a flow meter, a pressure sensor and a temperature sensor.

[0025] [Fig.2] illustrates the steps in the process of controlling a flow measurement of filling according to the invention;

[0026] [Fig.3] illustrates curves of evolution of physical parameters during a test filling of a test tank connected to a distribution station of the [Fig. 1]: the temperature, pressure and flow measured at the distributor, the pressure measured in the test tank.

[0027] Fig. 1 illustrates a reservoir 10 to be filled from a pressurized fluid distribution station 100.

[0028] The tank 10 to be filled may be that of a vehicle 20, and in particular a fuel cell vehicle. In this case, the tank 10 to be filled may be located inside the vehicle 20.

[0029] The distribution station 100 includes a source 2 containing the pressurized gaseous fluid, a distributor 4 connected to the source 2, and a supply hose 6 connected to the distributor 4 and intended to be connected to the tank 10 to be filled.

[0030] In addition, the distribution station 100 includes a flow and / or pressure control valve 8 disposed between the source 2 and the distributor 4. In particular, the distributor 4 includes a pressure sensor, a temperature sensor, and a flow meter which measures the flow of the fluid supplied to the tank 10 to be filled.

[0031] The reservoir 10 to be filled can be provided with a receptacle which ensures fluidic and mechanical coupling with the supply hose 6.

[0032] When the tank 10 is located inside a vehicle 20, the receptacle is fixed to the outside of the vehicle to ensure the connection between the tank 20 and the supply hose 6. A receiving conduit then connects the receptacle to the internal volume of the tank 10.

[0033] During the filling of a tank 10 of vehicle 20 attached to the distribution station 100, the flow meter installed at the distributor 4 measures the flow of the fluid which is delivered to the tank 10 for several purposes.

[0034] First, the measured flow rate allows the initial volume of tank 10 and the filling protocol to be applied for the remainder of the filling process to be determined. Second, the measured flow rate ensures compliance with predefined safety criteria by estimating the pressure and temperature of the fluid in tank 10 using physical models at each stage of the filling process. Finally, the measured flow rate allows the mass of fluid injected into tank 10 to be determined for billing purposes.

[0035] In the event of a flow meter failure and an erroneous flow measurement, the data based on this measurement, namely the initial volume of the tank 10, the filling protocol to be selected, the mass of fluid delivered, etc., are affected. This compromises, in particular, the safety of the filling operations and distorts the measurement of the quantity of fluid to be billed.

[0036] To prevent the above inconveniences, with reference to [Fig.2], the invention proposes a new method for controlling the measurement of the filling flow rate of a tank 10 connected to a distribution station 100 as presented above.

[0037] The process comprises the following operations: - SI measurement of a data point lhgas_mes of the flow rate at a time t, the SI measurement being carried out using the flow meter installed at the distributor 4, - estimation S2 of a data point ihgas_est of the flow rate at distributor 4 at time t, - comparison S3 between the measured data point Jhgas_mes and the estimated flow rate at time t, - generation S4 of a signal representative of the reliability of the measured data fHgas_ww>s of the flow rate.

[0038] In particular, the S2 estimation is based on the following parameters: the pressure P disp of the fluid measured by the pressure sensor, the temperature Tdisp of the fluid measured by the temperature sensor, the pressure Ptank of the fluid in the tank 10 to be filled, a predetermined coefficient kv of hydraulic pressure losses, the losses being due to the supply hose 6.

[0039] Advantageously, the pressure Ptank of the fluid in the reservoir 10 to be filled is measured using a pressure sensor disposed in the reservoir 10. Alternatively, this pressure Ptank is calculated from a physical model or measured at the hose 6.

[0040] The comparison S3 between the measured data / hgas_mes of the flow rate and the estimated data ingas_est of the flow rate is carried out by a controller and aims to detect any discrepancy between these two data.

[0041] When the deviation recorded is greater than a given threshold value, the controller generates a signal which indicates that the measured flow rate data is erroneous, and that consequently the flow meter is defective.

[0042] Thus, based on the difference noted between the estimated data ingas_est of the flow rate and the measured data fhgas 0 of the flow rate, the method makes it possible to determine the state of the flow meter.

[0043] Advantageously, the estimated data Wgas_est of the filling flow rate at time t is obtained from a relation / formula or mathematical equation ffigalt) clu' is a function of a ratio between the coefficient kv of pressure losses and the square root of the temperature measured at the distributor.

[0044] In particular, the formula comprises a first sub-formula and a second sub-formula

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056] The first sub-formula allows us to estimate the flow rate for a pressure pdh^t) in distributor 4 less than twice the pressure PfanAt) in reservoir 2. This first sub-formula,}^ is a function of the square root of the difference between the pressure pdis^t] in distributor 4 and the pressure p in reservoir 10. The second sub-formula allows us to estimate the flow rate for a given pressure P(iisp(t) in distributor 4 is greater than twice the pressure p^ in reservoir 2. This second sub-formula is a linear function of the pressure Pdis^ in distributor 4. The sub-formulas and 20 can be expressed as follows: for P(Usp < 2Ptank: for Prfisp 5” 2P^ank • , kv l \ (2) AT—PdisAt] with: Pdisp{t) ct 1(0' resPecdvement 'a Pressure in the distributor 4 and the pressure in the tank to be filled 10, expressed in [p«(a)]; kv: the coefficient of hydraulic pressure losses due to the supply hose 6 and the receiving conduit specific to the tank to be filled 10, expressed in [sll; h 1 A: a coefficient depending on the density Pgas of the fluid at 0°C and 1.0135 bar (expressed in ) and the density Pair of Pair at 0°C and 1.0135 bar (expressed in ) in [*£]), the compressibility factor (ri of the fluid in the distributor (unitless). The coefficient A present in relations (1) and (2) above depends on a ratio between, on the one hand, the product of the air density Pa;r by the fluid density Pgas, and on the other hand the compressibility factor of the fluid in the distributor. The expression for the coefficient A can be given by: A = (3) y ^dis^P In the expression for the estimated flow rate (ingas esit) given by relation (1) above, the pressure p^ of the fluid in the reservoir 10 to be filled is generally unknown

[0057]

[0058] for distribution station 100. This pressure p^ can be deduced from the pressure Pdjs^ measured by the pressure sensor installed at distributor 4. In particular, the pressure p^ in the tank 10 at a given time can be deduced from the pressure Pdisp(t] in the distributor 4 measured at a previous or later time. To deduce p^ from the invention, one relies on the teachings a test of filling a test tank from a dispensing station as described above. The test includes at least one stop phase. The test tank is equipped with at least one pressure sensor.

[0059] Figure 3 illustrates the evolution curves of physical parameters recorded during such a test. These include the pressure, temperature and flow rate of the fluid at the distributor 4 of the station, and the pressure of the fluid in the test tank.

[0060] We observe on this [Fig.3] that, during a stop phase [P^ Tc] of filling (here during the first stop phase), the pressure P disp of the fluid in the distributor 4 falls from a first maximum Pdisp_maxï measured at a first instant to a minimum Pj^^ measured at a second instant. The second instant C being subsequent to the first instant 6.

[0061] It is also observed that the fluid pressure in the distributor 2 reaches a second maximum Pdîsp_max2 measured at a fourth instant, starting from a minimum P disp min measured at a third instant £3. The fourth instant ^4 is subsequent to the third instant ^3.

[0062] In particular, at the second instant O and at the third instant / 3, the pressure P disp measured in the distributor 4 is identical to the pressure P tank measured in the test tank 10. This marks a pressure equilibrium between the distributor 4 and the test tank 10, but also between the hose 6 and the test tank.

[0063] This pressure equilibrium between times ^2 and #3 is expressed by the following relation: Pdisp ( ^2 ) ~ P tank ( ^2 ) P disp ( ^3 ) — P tank ( ^3 ) 00'

[0064] More generally, it is observed that the pressure Pdisp in the distributor 4 (and also in the hose 6) equalizes with the pressure Pj^ in the reservoir 10 immediately after the mass flow stops. Similarly, immediately after refilling resumes, the pressure Pdisp in the distributor 4 (and also in the hose 6) is close to or equal to the pressure Pdisp in the reservoir 10.

[0065] Furthermore, during the shutdown phase [TA, Tc], the flow measurement suggests that the mass of fluid introduced into the test tank 10 is negligible compared to the mass already present in said tank 10.

[0066] Thus, the pressure P^nk of the fluid in the reservoir 10 at the second instant ?? is substantially equal to the pressure Ptank of the fluid in the reservoir 10 at the first instant 6, the first instant 6 being prior to the second ?2- Similarly, the pressure Ptank of the fluid in the reservoir 10 at the third instant £3 is substantially equal to the pressure Ptank of the fluid in the reservoir 10 at the fourth instant ^4, the fourth instant ?4 being subsequent to the third instant (3.

[0067] From the above, the following relationship can be derived: ^tanki^Ù ~ ^tank^l) ^tank^-Ù — T*tankk^3) 00

[0068] From relation (4) and relation (5), we deduce: Ptankk^Ù = PdisiÀt^) Ptank^A^ ~ Pdispit^) (ô)

[0069] Thus, advantageously, in order to determine the pressure Ptank in the reservoir 10 to be filled, and to estimate the flow rate data rngûs, the process includes at least one stop phase [^ Tc],

[0070] This shutdown phase [TA, Tc] comprises two time intervals [TA, Tg], [TB, Tc] in each of which the pressure P disp in the distributor 4 varies and exhibits a maximum P disp max and a minimum P disp min. The estimation S2 of the data nigas_est of the filling flow rate can be carried out on any one of the intervals [Ta, Tb], [Tb, Tc],

[0071] The estimation S2 of the data ingas «s / of the flow rate over the first time interval [ Ta, Tg] is carried out from a first data Pdisp_l of the pressure P disp in the distributor 4 at a first instant 6, and from a first data Ptankj of the pressure Ptank in the reservoir 10 at the first instant 6.

[0072] The first Pdisp_l value of the fluid pressure Pdisp in the distributor 4 at the first instant 6 is equal to the maximum value Pdisp_max of the pressure measured by the pressure sensor over the first interval rCv TB],

[0073] The first data Ptankj of the pressure Ptank in the reservoir 10 at time 6 can be deduced from a second data Ptank1 of the pressure Ptank in the reservoir 10 at a second time h and from a second data Pdispjl of the pressure Pdisp in the distributor 4 at the second time ?2- The second time ^2 is later than the first time 6 and coincides with the second boundary ^ of the first interval [TA, TB],

[0074] More specifically, the first value Ptank_i of the pressure Ptank in the tank 10 at the first instant 0 is equal to the second value Ptankji of the pressure Ptank in the tank 10 at the second instant. The latter is equal to the second value Pdisp_2 of the pressure Pdisp of the fluid in the distributor 4 at the second instant. ^2-

[0075] The second data Pdùpl of the pressure Pdisp of the fluid in the distributor 4 at the second instant L is equal to the minimum value P disp mini measured by the pressure sensor on the first interval [7^ Ps].

[0076] The estimation of the flow rate data ^«s_«s? over the second time interval [ TB, Tc\ is performed from a fourth data point Pdisp_A^ the pressure P disp in the distributor 4 at a fourth instant and from a fourth data point P tank of the pressure Ptank in the reservoir at the fourth instant

[0077] The fourth data PdispA of the pressure P disp of the fluid in the distributor 4 at the fourth instant is equal to the maximum value Pdisp_max2 of the pressure measured by the pressure sensor on the second interval [TB, Tc],

[0078] The fourth data point Plank_4 of the pressure Ptank in the reservoir 10 is deduced from a third data point Ptankj of the pressure Ptank in the reservoir 10 at a third instant ^3, and from a third data point P disp 3 of the pressure P disp in the distributor 4 at the third instant ^3. The third instant ^3 is prior to the fourth instant ^4, and coincides with the first terminal TB of the second interval [TB, Tc\.

[0079] More specifically, the fourth data point Ptankji, representing the pressure Ptank in reservoir 10 at the fourth instant ^4, is equal to the third data point Ptmkj, representing the pressure Ptank in reservoir 10 at the third instant ^3. This last data point is equal to the third data point Pdisp_3, representing the pressure Pdisp in distributor 4 at the third instant h-

[0080] It should be noted that the third data Pdisp_3 of the pressure Pdisp of the fluid in the distributor 4 at the third instant f^cst equals the minimum value Pdisp min2 measured by the pressure sensor on the second interval [TB, Tc\.

[0081] Advantageously, the method includes an operation S5 consisting of comparing the flow rate data ïhgas_mes measured at the second instant L (respectively at the third instant ^3) with a first predefined threshold value

[0082] In addition or as an alternative, the operation S5 compares the difference between the second data P disp J. and the first data Pdisp] (respectively the difference between the fourth data Pdispjl and the third data Pdisp„3) of the pressure Pdisp of the fluid in the distributor with a second predefined threshold value e2.

[0083] The equality between the first data point PtankJ of the pressure Ptank in the reservoir 10 at the first instant 6 and the second data point Pdisp_2 of the pressure P^^ in the distributor 4 at the second instant (respectively between the fourth data point Ptank^ of the pressure P tank in the reservoir 10 at the fourth instant and the third data point Pdisp_3 of the pressure P disp in the distributor 4 at the third instant ^3) is admitted when one of the following criteria is satisfied: i) the data iïlgas_mes measured at the second instant b (respectively at the third instant ^3) by the flowmeter is less than the first predefined threshold value ii) the difference between the second data Pdisp_2 and the first data Pdispi (respectively between the fourth data PdiSp 4 and the third data Pdîsp_l) of the pressure P disp of the fluid in the distributor is less than the second predefined threshold value e2.

[0084] Advantageously, the stop phase [^ Te] of filling is part of a leak test operation intended to check the tightness of a fluid connection between the supply hose 6 and the tank 10 to be filled.

[0085] Advantageously, the pressure loss coefficient kv is the sum of a first component kvX relating to pressure losses due to the supply hose 6, and a second component ^2 relating to pressure losses due to a receiving conduit specific to the tank to be filled.

[0086] The present method offers the advantage of estimating a mass flow rate without a flow meter, using only pressure and temperature data from the filling station 100, data considered reliable and easily accessible using measurement means from the filling station.

Claims

Demands

1. A method for controlling the flow rate measurement of a filling tank (10) connected to a pressurized fluid distribution station (100), the station (100) comprising a fluid source (2), a distributor (4) connected to the source (2), and a supply hose (6) connected to the distributor (4) and intended to be coupled to the tank (10) to be filled, the distributor (4) being equipped with a pressure sensor, a temperature sensor, and a flow meter, the method comprising the following operations: - measurement (S1) of a flow rate value (nigas_mes) at a determined time (t) using the flow meter installed at the distributor (4), - estimation (S2) of a flow rate value (nigas_est) at the distributor (4) at time (t), the estimation being based on the following parameters: the fluid pressure (Pjtsp) measured by the pressure sensor, the fluid temperature (T^p) measured by the temperature sensor. temperature,the pressure (Ptank) of the fluid in the tank (10) to be filled, measured using a pressure sensor placed in the tank (10) or calculated from a physical model, a predetermined coefficient (kv) of hydraulic pressure loss, the losses being due to the supply hose (6) and a receiving conduit specific to the tank to be filled (10), - comparison (S3) between the measured data (nigas_mes) and the estimated data (ntgas_est) of the flow rate at time (t), - generation (S4) of a signal representative of the reliability of the estimated data (Qngasjmes) of the flow rate.

2. A method according to the preceding claim, wherein the estimated (ingas_est) of the filling flow rate at time (t) is obtained from a predetermined calculation formula that is a function of a ratio between the predetermined coefficient of pressure losses and the square root of the temperature measured at the distributor (4), the calculation formula comprising: - a first sub-formula allowing estimation of the flow rate for a pressure (p₀) in the distributor (4) less than twice the pressure (p(t)) in the tank (10), the first tank sub-formula being a function of the square root of the difference between the pressure / „ / in distributor (4) and the ' dis [h / / pressure / p M) in tank (10), and tankV / - a second sub-formula / ' / Yi allowing the estimation of the flow rate for a pressure in distributor (4) greater than twice the pressure / p / Àj in tank (10), the second ' tankx / / sub-formula / ( being given by a linear function per ^gas^ / ) with respect to the pressure O in distributor (4). 3 disj\ / /

3. A method according to the preceding claim, wherein the first and second subformulas ,0, ^)) are expressed respectively as follows: / \ t L / / Yr ' For ^disp ^-^tank meaK ik-^T^V / V d -(P ,k \ / r 11 mi l) A. M • for P disp > ^*lupk tilgas? ( 0 Æ । ,, <Pdism t1 \ / avec: P / Hsp^} ct Pt ’ resPecdvement la pression dans le distributeur (4) et la pression dans le réservoir (10), exprimées en [p#]; kv : le coefficient de pertes de charge hydraulique dues au flexible d’alimentation et au conduit de réception propre au réservoir à remplir, exprimé en [»dl; h J A : un coefficient dépendant de la masse volumique Pgas du fluide à 0°C et 1.0135 bar (exprimée en [*£]), la masse volumique Pair m3 J de l’air à 0°C et 1.0135 bar (exprimée en ), le facteur de [m! compressibilité Z^p(t) du fluide dans le distributeur (exprimé sans unité).

4. A method according to the preceding claim, wherein the coefficient (A) depends on a ratio between, on the one hand, the product of the air density (Pair) and the fluid density (Pgus), and on the other hand the compressibility factor (z^J^) of the fluid in the distributor (4), the expression for the coefficient (A) being given by: 4 H 1 I^S^air A = 32L\ / -—~~

5. A method according to any one of the preceding claims, comprising at least one stop phase ([T'a, Tc]) of the filling, the pressure (Ptank) in the tank (10) being deduced from the pressure (Pdisp) in the distributor (4) measured immediately before the stop phase ([TA, T^]) of the filling and / or after the stop phase ([T4, ^]) of the filling.

6. Method according to the preceding claim, wherein the at least one stop phase ([T4, Tc]) of the filling comprises two time intervals (([^ ^b]), ([^ Tc])) in each of which the pressure in the distributor (4) varies and has a maximum (p) and a minimum (Pd^n mm), the estimation of \rdisp_max) v atspjmn / , the data Qngas_est) of the filling flow rate being carried out on any one of said intervals (([T'a, Tb]), ([Tb> ^c])).

7. A method according to the preceding claim, wherein a) the estimation of the flow rate data (tngas es^) over the first time interval ([TA, Tb]) is performed from a first data point (pa) of the pressure (Pdisp) in the distributor (4) at a first instant (0), and from a first data point (Ptankj) of the pressure (Ptank) in the tank (10) at the first instant (ri), the first data point (PtankS) of the pressure (Ptank) in the tank (10) at the first instant (0) being deduced from a second data point (p) of the pressure (Ptank) in the tank (10) at a second instant (2) and from a second data point (Pdisp_2) of the pressure (Pdisp) in the distributor (4) at the second instant (2), the first instant (1) being prior to the second instant (2), the second instant (3 / 4) coinciding with the second terminal of the first interval (|Tv T b]) and b) the estimation of the data (ûigas_est) of the flow rate over the second time interval ([TB,Tc]) is performed from a fourth data point (Pdispjù) of the pressure (Pdisp) in the distributor (4) at a fourth instant (^4), and from a fourth data point (Ptank_4) of the pressure (Ptank) in the reservoir (10) at the fourth instant (^4), the fourth data point (Ptankji) of the pressure (Ptank) in the reservoir (10) being deduced from a third data point (p ) of the pressure (Ptank) in the reservoir (10) at a third instant ( / 3), and from a, third data (Pj^a) of the pressure (Pdtsp) in the distributor (4) at the third instant (^), the fourth instant (^4) being posterior to the third instant ^ ), the third instant (^3) coinciding with the first boundary of the second interval ([?B, 7^]).

8. A method according to the preceding claim, wherein - the first datum (pdisp) of the pressure (Pdisp) of the fluid in the distributor (4) at the first instant (0) is equal to the maximum value (pdj mav^) of the pressure measured by the pressure sensor over the first interval ([T1^ 7^1], - the fourth datum (pdi j) of the pressure (Pdisp) of the fluid in the distributor (4) at the fourth instant (^4) is equal to the maximum value (p„ ) of the pressure measured by the pressure sensor (aisp_max2} KKK over the second interval ([Tp, 7'c])_

9. A method according to any one of claims 7 or 8, wherein - the second data (paj of the pressure (Pdisp) of the fluid in the distributor (4) at the second instant (^2) is equal to the minimum value \ measured by the pressure sensor on the ' disp_tmn) first interval ( [7^, TB\\ - the third data (pdi of the pressure (Pdisp) of the fluid in the distributor (4) at the third instant (£3) is equal to the minimum value / p 1 measured by the pressure sensor on the ' disp_min) second interval ([T1B, T'c]).

10. A method according to any one of claims 7 to 9, wherein - the first data (Ptankj) of the pressure (Ptank) in the reservoir (10) at the first instant (b) is equal to the second data (pdi J) of the pressure (Pdisp) of the fluid in the distributor (4) at the second instant (^2), - the fourth data (Ptankj) of the pressure (Ptank) in the reservoir (10) at the fourth instant (£4) is equal to the third data (pdis) of the pressure (Pdisp) in the distributor (4) at the third instant (£3).

11. A method according to any one of claims 7 to 10, comprising a step (S5) of comparing: i) the data (W^mes) measured by the flowmeter at the second instant (^2), respectively at the third instant ( / 3), with a first predefined threshold value (é i); and / or ii) the difference between the second data (pdjsp 2) and the first data (pdi respectively between the fourth data (pdj 4) and the third data (pdi 3), of the pressure (Pdisp) of the fluid in the distributor (4) with a second predefined threshold value (¾).

12. A method according to the preceding claim, wherein the equality between the first data point (Ptank_i) of the pressure (Ptank) in the tank (10) at the first instant (0) and the second data point (pdj) of the pressure (Pdîsp) in the distributor (4) at the second instant (2), respectively between the fourth data point (Ptank„4) of the pressure (Ptank) in the tank (10) at the fourth instant (4) and the third data point (p^) of the pressure (Pdîsp) in the distributor (4) at the third instant (3) is admitted when one of the following criteria is satisfied: i) the data point (rngas_mes) measured by the flowmeter at the second instant (2), respectively at the third instant (3), is less than the first predefined threshold value (ei), ii) the difference between the second data point (pdü) and the first data point (pdi) respectively between the fourth data point (pdl j) and the third data point (pdi 3),the pressure (Pdisp) of the fluid in the distributor (4) is less than the second predefined threshold value (,

13. A method according to any one of claims 4 to 12, wherein the stop phase ([^ Tc]) of filling is part of a leak test operation intended to check the tightness of a fluid connection between the supply hose (6) and the tank (10) to be filled.

14. A method according to any one of the preceding claims, wherein the pressure loss coefficient (kv) is the sum of a first component (kv) relating to losses due to the supply hose, and a second component (kv2) relating to losses due to a receiving conduit attached to the tank (10) to be filled.

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