Patent Publication Number: US-2023135470-A1

Title: Method and Device for Assisting Filling with Hydrogen

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a 371 of International Application No. PCT/EP2021/053632, filed Feb. 15, 2021 which claims priority under 35 U.S.C. § 119 from German Patent Application No. 10 2020 106 622.8, filed Mar. 11, 2020, the entire disclosure of which is herein expressly incorporated by reference. 
    
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
     The technology disclosed here relates to a method and a corresponding device that assist a user of a vehicle when refueling with hydrogen. 
     An electrically driven vehicle can comprise a fuel cell that is designed to generate electrical energy for an electric drive motor of the vehicle on the basis of hydrogen. The vehicle comprises a hydrogen pressure tank that is designed to be filled with hydrogen up to a certain filling pressure (e.g. up to 700 bar). The range of the vehicle depends on the amount of hydrogen that is filled into the hydrogen pressure tank in a refueling operation, with the amount of hydrogen in turn depending on the filling pressure to which the hydrogen pressure tank is filled in the refueling operation. 
     The filling pressure in a refueling operation typically depends on properties of the vehicle and/or the hydrogen fuel station. In this case, the filling pressure can be reduced due to limitations on the side of the vehicle and/or the hydrogen fuel station, which in turn leads to a reduced range of the vehicle and thus to reduced comfort for a user of the vehicle. 
     It is one preferred object of the technology disclosed herein to reduce or eliminate at least one disadvantage of a previously known solution or to propose an alternative solution. In particular, it is one preferred object of the technology disclosed herein to assist a user of a vehicle when refueling with hydrogen and/or to increase the quality of hydrogen refueling. Other preferred objects can arise from the advantageous effects of the technology disclosed herein. The object is achieved by the subject matter of the independent claims. The dependent claims represent preferred embodiments. 
     According to one aspect, a device for assisting in refueling of a pressure tank of a (motor) vehicle with fuel is described. The device can form part of the vehicle, part of the fuel station for a refueling operation for refueling the pressure tank and/or part of a central unit (e.g. a backend server) for a network of fuel stations. The device can be designed to assist refueling in such a way that when refueling, whenever possible, or as often as possible, the maximum possible amount of fuel (in particular H 2 , or hydrogen) can be filled into vehicles&#39; pressure tanks. 
     The device is configured to determine whether a refueling operation for refueling the pressure tank at a fuel station has taken place with or without a communication link between the vehicle and the fuel station. The communication link between the vehicle and the fuel station can allow communication according to the SAE J2601 standard and/or the SAE J2799 standard. Alternatively or additionally, the communication link between the vehicle and the fuel station can comprise, in particular be, an infrared communication link. In particular, the SAE J2601 standard can specify infrared communication used between the vehicle and the fuel station. The communication link can potentially be limited to a communication direction from the vehicle to the fuel station. 
     Where applicable, the communication connection can comprise one or more other forms of data transmission (such as Bluetooth or Wi-Fi) in addition to infrared communication, which can be used, for example, to transmit the vehicle identifier and/or position data. 
     It can thus be determined whether COM refueling or non-COM refueling of the pressure tank of the vehicle has taken place at the fuel station. In the case of refueling with a communication connection (i.e. COM refueling), the filling pressure of the pressure tank (and thus also the fuel filling quantity effected) is typically higher than when refueling without a communication connection (i.e. non-COM refueling), e.g. by 5% or more, or by 10% or more. Non-COM refueling can therefore lead to a reduced filling level of the pressure tank and thus to a reduced range of the vehicle. 
     The device is also configured, depending on whether refueling has taken place with or without communication, to effect a measure for a subsequent refueling operation. In particular, the device can be configured to effect a measure for a subsequent refueling operation if it is determined that refueling has taken place without a communication connection. Exemplary measures are: initiating a check of a communication module for establishment of the communication connection with respect to the vehicle and/or the fuel station; and/or updating a database indicative of a status of the fuel station. 
     The device thus makes it possible to detect a limitation for a vehicle (e.g. a (any) first vehicle from a plurality of different vehicles) and/or a fuel station (e.g. a (any) first fuel station from a plurality of different fuel stations) resulting in the filling level of a pressure tank in a refueling operation, and thus the range of a vehicle, being limited. Furthermore, the device allows the limitation to be corrected promptly in order to bring about the maximum possible filling level in subsequent refueling operations. In this way, the refueling quality for pressure tanks can be reliably increased. 
     The device can be configured to determine that a plurality of consecutive operations of refueling the pressure tank of the vehicle (in particular the first vehicle from the plurality of different vehicles) at a corresponding plurality of different filling stations have taken place without a communication connection. This can be taken as an indication that the vehicle&#39;s communication module is impaired. In response thereto, it can be brought about for the communication module of the vehicle to be checked for establishment of the communication connection, and in particular repaired or replaced. In this way, the quality of the vehicle&#39;s refueling operations can be increased in a timely manner. 
     Alternatively or additionally, the device can be configured to determine that a plurality of consecutive refueling operations at the fuel station (in particular at the first fuel station from the plurality of different fuel stations) for the pressure tanks of a corresponding plurality of different vehicles have taken place without a communication link. This can be taken as an indication that the station&#39;s communication module is impaired. In response thereto, it can be brought about for the communication module of the fuel station to be checked for establishment of the communication connection, and in particular repaired or replaced. In this way, the quality of refueling operations at the fuel station can be increased in a timely manner. 
     The device can be configured to determine pressure data relating to the filling pressure of the pressure tank following the refueling operation. Furthermore, the device can be configured to determine temperature data relating to the temperature of the fuel in the pressure tank (in particular the temperature of the fuel following the refueling operation). 
     It can then be accurately determined on the basis of the pressure data and/or on the basis of the temperature data whether or not a refueling operation has taken place with or without a communication link between the vehicle and the fuel station. In particular, it can be detected that a refueling operation has taken place without a communication connection if the filling pressure is lower (e.g. lower by 5% or more) than a maximum allowable pressure for a refueling operation. 
     The density of the fuel in the pressure tank can be determined on the basis of the pressure data and the temperature data. The SOC (state of charge) of the pressure tank can then be accurately determined from the density of the fuel in the pressure tank reached in the refueling operation. Based on the SOC, it can then be determined whether a refueling operation has taken place with a communication link (SOC&gt;95%) or whether a refueling operation has taken place without a communication link (SOC&lt;95%). 
     The device can be configured to determine whether a user and/or the fuel station prematurely terminated the refueling operation (and therefore the SOC of the pressure tank could not reach the 95% of the maximum allowable pressure). For this purpose, zero, one or more indicators of premature termination (before the maximum allowable pressure has been reached) can be determined. Exemplary indicators are:
         pressing an abort button (vehicle or fuel station side);   an abort signal on the communication link (vehicle or fuel station side); and/or   the fact that the filling pressure is well below the maximum allowable pressure, e.g. 80% or lower than the maximum allowable pressure.       

     On the basis of the zero, one or more detected indicators relating to premature termination of the refueling operation, the device can also be configured to determine whether a refueling operation for refueling the pressure tank at the fuel station has taken place with or without a communication link between the vehicle and the fuel station. By detecting and taking into account one or more indicators of premature termination of the refueling operation, it can be determined with increased accuracy whether a refueling operation has taken place with or without a communication link. 
     As already mentioned above, the device can form part of the vehicle. The device can be configured to receive refueling operation data relating to whether the refueling operation has taken place with or without a communication link between the vehicle and the fuel station from the fuel station or from a central unit for a network of fuel stations. 
     For this purpose, the device can be configured to determine an identifier of the vehicle, position data relating to the position of the fuel station and/or a time stamp relating to a point in time of the refueling operation. The refueling operation data can then be reliably requested from the fuel station or the central unit using the identifier, using the position data and/or using the time stamp. Providing refueling operation data can allow a vehicle to reliably detect an impairment of the vehicle&#39;s communication module. 
     The fuel station can comprise one or more fuel station sensors which are configured to collect sensor data relating to the fuel, in particular relating to the pressure and/or the quantity of fuel that is provided in the refueling operation. The one or more fuel station sensors can have a relatively high level of accuracy. In particular, the one or more fuel station sensors can be calibrated. 
     The vehicle can comprise one or more vehicle sensors which are configured to collect sensor data relating to the filling level and/or the filling pressure of the pressure tank. The device can be configured to check and/or calibrate the one or more vehicle sensors on the basis of the sensor data from the one or more fuel station sensors. In this way, the quality of refueling operations can be further increased. 
     According to a further aspect, described herein is a (road) motor vehicle (in particular a motor car or a truck or a bus) that comprises the device described herein. 
     According to a further aspect, described is a fuel station that comprises the device described herein. 
     According to a further aspect, a method for assisting in refueling a pressure tank of a (first) vehicle with (a gaseous or liquid) fuel is described. The method comprises determining whether a refueling operation for refueling the pressure tank at a (first) fuel station has taken place with or without a communication link between the (first) vehicle and the (first) fuel station. Furthermore, the method comprises, depending thereon, effecting a measure for a subsequent refueling operation (for the (first) vehicle and/or the (first) fuel station). 
     According to a further aspect, a software (SW) program is described. The SW program can be configured to be executed on a processor and thereby to carry out the method described herein. 
     According to a further aspect, a storage medium is described. The storage medium can comprise a SW program configured to be executed on a processor and thereby to carry out the method described herein. 
     It should be noted that the methods, devices and systems described herein may be used either on their own or in combination with other methods, devices and systems described herein. In addition, any aspects of the methods, devices and systems that are described herein may be combined with one another in a wide variety of ways. In particular, the features of the claims may be combined with one another in a wide variety of ways. 
     The invention is described more thoroughly below on the basis of exemplary embodiments, wherein 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    shows an exemplary system for carrying out pressure refueling, in particular hydrogen refueling; and 
         FIG.  2    shows a flowchart of an exemplary method for assisting a user when carrying out pressure refueling (e.g. with hydrogen). 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     As explained at the outset, the present document is concerned with increasing the comfort and/or the reliability and/or the quality of pressure refueling of a pressure tank with a fuel, in particular with hydrogen. In this context,  FIG.  1    shows an exemplary system  100  which comprises a vehicle  110  with a pressure tank  111  and a tank unit or a fuel station  120  for refueling the pressure tank  111  with a fuel (in particular with hydrogen, H 2 ). The fuel station  120  comprises a fuel hose  121 , which can be connected to a coupling element  112  of vehicle  110  via a complementary coupling element  122  in order to create a fluid-tight, in particular gas-tight connection between the fuel hose  121  and a fuel line  114  of the vehicle  110  to the pressure tank  111 . To refuel, fuel can be pumped from the fuel station  120  via the fuel hose  121  and via the fuel line  114  into the pressure tank  111 . 
     The vehicle  110  can comprise a communication module  113  which is designed to exchange data relating to a refueling operation with a corresponding communication module  123  of the fuel station  120 . A communication link  103  can thus be established between a vehicle  110  and a fuel station  120  in order to monitor a refueling operation. The communication can take place via an infrared (IR) interface. 
     The communication link  103  can be used to transmit pressure data relating to the pressure in the pressure tank  111  to the fuel station  120 . The fuel station  120  can then operate the pump for filling the pressure tank  111  as a function of the pressure data, in particular in order to fill the pressure tank  111  with fuel up to a certain maximum pressure. 
     If no communication connection  103  can be established between the vehicle  110  and the fuel station  120 , the filling pressure that is reached in a refueling operation is typically lower than the possible maximum pressure for safety reasons. In particular, in such a case (which is also referred to as non-COM refueling) a lower filling pressure is reached for the pressure tank  111  than in the case of refueling with data communication (also referred to as COM refueling), since the fuel station  120  can only estimate the actual filling pressure in the pressure tank  111  (as it is not communicated via the communication link  103  from the vehicle  110 ). The filling pressure reached in non-COM refueling can be, for example, about 5% or more, or 10% or more (e.g. 8%) below the possible maximum pressure. The reduced filling pressure leads to a reduced range for the vehicle  110 . 
     A defect in and/or soiling of the communication module  113  of the vehicle  110  and/or the communication module  123  of the fuel station  120  can result in only non-COM refueling with reduced filling pressure and no COM refueling with maximum pressure being carried out. 
     For refueling with hydrogen or H 2 , the aspects of COM refueling and non-COM refueling are defined in the SAE J2601 standard document. This standard document is incorporated herein by reference in its entirety. According to SAE J2601, COM refueling with maximum pressure only takes place if a valid data connection  103  has been established between the vehicle  110  and the fuel station  120 . The aspects relating to the data link  103  are described in the SAE J2799 standard document, which is incorporated herein by reference in its entirety. 
     Non-COM (i.e. non-communication) refueling takes place when the data connection  103  between the vehicle  110  and the fuel station  120  cannot be established or when the data received by the fuel station  120  are not recognized as valid by the fuel station  120 . A refueling operation may initially start as COM refueling, but switch to non-COM refueling if there is a problem with signal transmission during refueling. In this case, the fuel station  120  determines a new (reduced) target pressure for the refueling operation. 
     The system  100  can comprise a central unit  130  which is configured to communicate with the tank unit or fuel station  120  and/or with the vehicle  110  via a communication link  131 . In particular, the central unit  130  can be configured to determine whether COM refueling or non-COM refueling has been carried out at a fuel station  120 . Furthermore, the central unit  130  can determine for a plurality of different refueling operations (each with different vehicles  110 ) whether COM refueling or non-COM refueling has been carried out. Based on this data, it can be checked whether a fuel station  120  has a (permanent) defect in relation to the establishment of a communication link  103 . This information can be communicated in order to inform the users of vehicles  110  whether only reduced refueling is possible at the fuel station  120  or whether full refueling is possible. 
     It can thus be detected, in particular at the end of an operation of refueling a pressure tank  111  (by the vehicle  110 ), whether non-COM refueling or COM refueling has been carried out (e.g. on the basis of the filling pressure in the pressure tank  110 ). This information can be stored in a database and, where applicable, taken into account in journey planning (for subsequent refueling, also for other vehicles). 
     The information relating to the type of refueling that has taken place (COM refueling or non-COM refueling) can be transmitted to the fuel station  120  via vehicle-to-infrastructure communication, in particular in order to cause an operator of the fuel station  120  to rectify the error (if it is a fuel station error). If the cause lies with the vehicle  110 , a corresponding error entry can be stored in an error memory of the vehicle  110  in order to cause the error to be corrected as part of the maintenance for the vehicle  110 . 
     A database relating to the type of refueling (COM or non-COM refueling), which is determined and updated by the central unit  130  for example, can allow a vehicle  110 , for example, to determine whether the RDI (refueling data interface) signal transmitted by the communication module  113  of the vehicle  110  (e.g. via an infrared-based communication link  113 ) for a refueling operation has been successfully received by the fuel station  120 . The RDI signal can be defined in the SAEJ2601 standard. If the signal was not received, and if it is detected that this is the case at multiple fuel stations  120 , then it can be reliably concluded that the communication module  113  of the vehicle  110  is defective. 
     The comparison between a certain vehicle  110  and a refueling operation can be achieved, for example, by transmitting an identifier (ID) of the vehicle  110  to the fuel station  120  as part of the data communication  103  (e.g. the vehicle identification number, VIN). Alternatively or additionally, a first database for fuel stations  120  and a second database for vehicles  110  can be maintained, in which individual refueling operations are listed with a time stamp and/or with position data (e.g. GPS coordinates). A match between a vehicle  110  and a certain refueling operation at a certain fuel station  120  can thus be reliably established. 
     A database relating to the individual refueling operations at at least one fuel station  120  can allow a vehicle  110  to determine information regarding how much fuel was taken on in one refueling operation. Alternatively or additionally, this can be determined from an electronic invoice for a refueling operation (which can be assigned to a specific refueling operation via position data and/or a time stamp, for example). 
     The quantity information provided by the fuel station  120  relating to the quantity of fuel provided can be compared with the vehicle&#39;s own filling measurement (taking into account the accuracy of the filling measurement), e.g. in order to detect an error in a refueling operation. In a corresponding manner, the quantity information determined by the vehicle  110  can also be transmitted to the fuel station  120  or to the central unit  130 . In this way, the quantity sensors of the vehicle  110  and of the fuel station  120  can be compared with one another. This is particularly advantageous for the calibration of the sensor  115  of a vehicle  110 , since the sensor system  125  of a fuel station  120  is typically calibrated and can therefore be used as a reference for calibrating the sensor  115  of the vehicle  110 . In particular, inaccuracy in the vehicle sensor  115  due to drift or aging can be detected and potentially compensated for. 
     The vehicle  110  can thus be configured to estimate the updated filling level of the pressure tank  111  online in a refueling operation on the basis of the currently present (measured) filling level of the pressure tank  111  and on the basis of the filling mass currently provided by the fuel station  120  and, where applicable, display it and/or use it in the calculation of the range of the vehicle  110 . Furthermore, on the basis of the filling mass provided by the fuel station  120 , the pressure or the temperature of the pressure tank  111  can be inferred via the density of the (gaseous) fuel. 
     The vehicle  110  can comprise one or more sensors  115  which are configured to collect sensor data relating to the filling level and/or the filling pressure of the pressure tank  111 . Furthermore, the fuel station  120  can comprise one or more sensors  125  which are configured to record sensor data relating to the pressure of the fuel provided and/or relating to the amount of fuel provided. The one or more sensors  125  of the fuel station  120  are typically calibrated. The sensor data provided by the one or more sensors  125  of the fuel station  120  can thus be used to check and/or calibrate the one or more sensors  115  of the vehicle  110 . 
     The database relating to a fuel station  120  can indicate
         whether and, if applicable, in what period of time the fuel station  120  is being serviced and is therefore not available for refueling; and/or   whether the fuel station  120  is defective; and/or   whether the fuel station  120  allows non-COM fueling or COM fueling; and/or   position data relating to the position at which a vehicle  110  should stop in order to allow coupling of the coupling elements  122 ,  112  (e.g. for fully automatic refueling); and/or   statistical data on the utilization of the fuel station  120  and/or on the price trend for fuel at the fuel station  120 .       

     The status of fuel stations  120  can thus be determined and updated (e.g. by the central unit  130 ). The database related to the status of fuel stations  120  can then be provided for refueling operations for vehicles  110 . 
       FIG.  2    shows a flowchart of an exemplary (potentially computer-implemented) method  200  for assisting in the refueling of a pressure tank  111  of a vehicle  110  with fuel. The pressure tank  111  can in particular be refueled with H 2 , or hydrogen. The method  200  can be carried out by the vehicle  110  and/or by the fuel station  120  at which a refueling operation for refueling the pressure tank  111  takes place. 
     The method  200  comprises determining  201  whether a refueling operation for refueling the pressure vessel  111  at a fuel station  120  has taken place with or without a communication link  103  between the vehicle  110  and the fuel station  120 . The vehicle  110  can be any first vehicle  110  from a plurality of different vehicles  110 . The fuel station  120  can be any first fuel station  120  of a plurality of different fuel stations  120 . In particular, it can be determined whether COM refueling or non-COM refueling has taken place. 
     Furthermore, the method  200  comprises, depending on whether a refueling operation has taken place with or without a communication link  103 , effecting  202  a measure for a subsequent refueling operation. A measure can be taken in particular when it has been recognized that a refueling operation has taken place without a communication link  103 . As a measure in this case, in particular, the communication module  113 ,  123  of the vehicle  110  and/or of the fuel station  120  can be checked and, where applicable, repaired. A measure for a subsequent refueling operation for the vehicle  110  (potentially at another fuel station) and/or for the fuel station  120  (potentially for refueling another vehicle) can thus be effected. 
     The measures described in this document can be used to increase comfort when refueling and using a vehicle  110  with a pressure fuel tank  111 . In particular, improved journey and/or range planning for vehicles  110  can be made possible by providing a database relating to the status of fuel stations  120 . The information determined in relation to non-COM refueling can be used to detect defects at an early stage and rectify them, so that the quality of refueling operations can be increased. In a corresponding manner, faults in a vehicle  110  can also be detected and rectified. Such a fault can be detected in particular when multiple consecutive non-COM refueling operations have taken place at different fuel stations  120 . 
     The present invention is not limited to the exemplary embodiments shown. In particular, it should be noted that the description and the figures are only intended to illustrate the principle of the proposed methods, devices and systems by way of example.