Trailer download system for gas refueling stations, particularly for hydrogen, and operating method thereof

Abstract

A trailer download system designed for increasing the pressure of a gas, especially hydrogen gas. The system comprises a gas compressing unit with an input connecting pipe for attachment to a trailer and an output connecting pipe for connection to a refueling station. The compressing unit features multiple compressing stages, each equipped with a compressor, a gas inlet for gas entry, and a gas outlet for the release of compressed gas. The stages are arranged in series. The system is distribution assembly, comprising a distribution pipeline that fluid-dynamically connects the input and output pipes with the inlets of each compressing stage. This connection is selectable to distribute gas from the trailer to one or more compressing stages, varying the gas pressure as needed before it enters the refueling station. The operation of this system involves a computer-implemented method.

Description

Trailer Download System for Gas Refueling Stations, particularly for Hydrogen, and Operating Method thereofDescriptionTECHNICAL FIELD

[0001] The present disclosure concerns trailer download system for hydrogen refueling station designed for reducing the energy consumption. More specifically, the present disclosure relates to the field of hydrogen gas handling, particularly to systems and methods for unloading hydrogen gas from trailers into a refueling station’s accumulator.BACKGROUND ART

[0002] In the current technology for unloading hydrogen trailers, the process involves an initial lamination of hydrogen flow at the first stage of a compressor. This step is necessary to regulate or adjust the flow and the pressure of the hydrogen being offloaded from the trailers, which may contain hydrogen at high pressures. The laminated hydrogen at a lower pressure is then recompressed to match the pressure levels of the refueling station’s accumulator.

[0003] In the current systems, the storage pressure for the hydrogen at the refueling station accumulators is maintained at a high level of 550bar or more. To accommodate this, hydrogen arriving from trailers, which is initially at a lower pressure range of 200-3 OObar (depending on trailer typology), must be elevated to match the storage pressure. This necessitates the use of a compressor capable of increasing the hydrogen pressure from 200-300 bar to the required 550 bar or more for storage compatibility.

[0004] In the future where the trailer pressure may reach or exceed the storage pressure, , there still remains a need for a compressor to download the trailer up to lower pressure. Even though the trailer pressure is higher, the compressor plays a crucial role in storage filling ensuring a consistent, controlled transfer of hydrogen to the storage system, maintaining system integrity and operational efficiency.

[0005] While the aforementioned process is standard, it is not without its drawbacks.The main issue lies in the significant energy loss during the lamination step. The energy required to recompress hydrogen from the laminated low pressure back to the higher accumulator pressure is substantial. This not only results in inefficiencies but also increases operational costs due to the additional energy required for recompression.

[0006] Also, an aspect of this process according to the prior art is that it remains in use even when the trailer’s pressure is already higher than the pressure levels at the lower stages of the compressor. This practice indicates a certain inefficiency, as it involves reducing the pressure only to increase it again to a level that was already initially exceeded by the trailer’s pressure itself.

[0007] The relevant prior art also comprises the patent document US 10 563 820 B2.

[0008] The present disclosure aims at addressing the inefficiencies and energy loss associated with the lamination and recompression steps in the conventional unloading of hydrogen trailers. By improving the flow and pressure management of hydrogen during the unloading process, the invention seeks to reduce energy consumption and provide a more cost-effective solution.SUMMARY

[0009] The subject matter disclosed herein concerns a trailer download system designed to facilitate the pressure enhancement of gases, notably hydrogen. This system is equipped with a gas compressing unit that comprises an array of compressing stages. Each stage has a compressor for gas compression, accompanied by gas inlets for the entry of gas to be compressed and gas outlets for the exit of compressed gas. The compressing stages are sequentially arranged to ensure efficient gas flow and compression.

[0010] A further aspect of the present disclosure is drawn to the inclusion of a distribution assembly within the trailer download system. This assembly comprises a distribution pipeline that connects the input and output connecting pipes to the inlets of each compressing stage. The feature of this system is the selective fluid-dynamic connections of the distribution assembly, enabling the distribution of gas from the trailer to one or more compressing stages based on the gas pressure at the input point, therebyoptimizing the pressure increase before the gas is channeled into the refueling station.

[0011] In another aspect, disclosed herein is a control logic unit integral to the trailer download system, which is connected to a valve unit associated with each compressing stage, facilitating the control over the gas distribution from the trailer through the opening of these valve units. This arrangement ensures that the gas pressure is adequately increased prior to its introduction to the refueling station, aligning with the system’s operational requirements.

[0012] A further aspect of the present disclosure is drawn to the detailed configuration of each valve unit within the system. Each valve unit comprises a control electro-valve and an actuator, both of which are controlled by the control logic unit. This arrangement allows for the regulation of the gas flow from the distribution pipeline to the compressors, further enhancing the system’s gas pressure management.

[0013] In another aspect, the subject matter disclosed herein concerns that one of the control electro-valves is of an adjustable type, facilitating the refined control over gas flow, while the remaining are of a switch-over type.

[0014] A further aspect of the present disclosure is drawn to the incorporation of pressure and / or temperature sensors within each valve unit. These sensors are placed along the pipeline to monitor the gas’s pressure and / or temperature.

[0015] In another aspect, disclosed herein is a distribution assembly, which comprises a main control valve and a pressure and / or temperature sensor, both of which are adapted to monitor and control the gas flow from the trailer.

[0016] In another aspect, the subject-matter disclosed herein concerns the integration of intercoolers connected to the gas outlets of each compressing stage. These intercoolers are suitable to maintain the gas at optimal temperatures throughout the compression process.

[0017] A further aspect of the present disclosure is drawn to the inclusion of a recycling mechanism within each compressing stage. This mechanism comprises a recycle line and a recycle valve, along with a check valve to prevent the backflow. The control logic unit controls these components to maintain the desired operating pressures.

[0018] In another aspect, disclosed herein is a method of operating the trailer download system, which is computer-implemented and designed to manage the pressure requirements of the gas before its transfer to a refueling station. This method involves acquiring gas pressure data, determining the necessary pressure increase, and sequentially opening control electro-valves to achieve the desired pressure levels.BRIEF DESCRIPTION OF THE DRAWINGS

[0019] A more complete appreciation of the disclosed embodiments of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:Fig. 1 illustrates a schematic of a trailer download system according to a first embodiment;Fig. 2 illustrates a trailer download system, according to a second embodiment; andFig. 3 is a flowchart of the operation method of the trailer download system.DETAILED DESCRIPTION OF EMBODIMENTS

[0020] According to one aspect, the present subject matter is directed to a more energy-efficient method for transferring hydrogen from a transport trailer to a refueling station’s accumulator. Unlike traditional systems that waste energy by reducing the hydrogen pressure significantly before recompression, the trailer download system directs the hydrogen to the most appropriate compressing stage based on the current pressure in the trailer. The system initially operates the lower stages of the compressor when the trailer’s pressure is high, instead filling directly into the higher stages of the multi-stage compressor. This avoids unnecessary pressure reduction and the subsequent need to recompress, which is energy -intensive.

[0021] As the pressure in the trailer drops over time, the system gradually redirects the hydrogen to the lower stages, step by step. Through this method of redirecting flow, it minimizes the energy typically consumed in the unloading process.

[0022] Referring now to the drawings, Fig.1 shows a trailer download system 1 according to a first embodiment.

[0023] The trailer download system 1 comprises a distribution assembly 4, pressure control valves, switch-over valves, (better defined below) and a control logic unit 3.

[0024] The compressing unit 2 comprises an input connecting pipe 25, designed to be connected to the trailer T carrying the gas, and an output connecting pipe 26, which serves as the conduit for transferring the pressurized gas into the refueling station R. Within the input connecting pipe 25 and the output connecting pipe 26 there is a plurality of compressing stages 21, 22, 23, 24, 2N. In the embodiment shown in Fig. 1, the compressing stages 21, 22, 23, and 24 are four, but in other embodiments, the number of compressing stages can be different according to the specific needs.

[0025] Each compressing stage 21, 22, 23, 24 is equipped with a compressor 214, 224, 234, 244. These compressors 214, 224, 234, 244 are responsible for the actual compression of the hydrogen. Each compressing stage 21, 22, 23, 24 has a gas inlet 211, 221, 231, 241 for the entry of gas to be compressed and a gas outlet 212, 222, 232, 242 from which the compressed gas exits. The compressing stages 21, 22, 23, 24 are arranged in a series configuration for efficient gas compression, as shown in the figure.

[0026] In an embodiment, the compressing values of the compressors 214, 224, 234, 244 may have the following compressing ratios:- the first stage 21, the one connected through the relevant valve unit 215, has the relevant compressor 214 capable of compressing the gas from 30 bar to 65 bar;- the second following stage 22 has the relevant compressor 224 capable of compressing the gas from 65 bar to 130 bar;- the third following stage 23 has the relevant compressor 234 capable of compressing the gas from 130 bar to 265 bar; and- the fourth following stage 24 has the relevant compressor 244 capable of compressing the gas from 265 bar to 550 bar.

[0027] The compressing rations provided above are for illustrative purposes only and should not be construed as limiting. It is understood that in various other implementations or systems, different compression parameters / ratios may be employed based onspecific requirements, conditions, or desired outcomes. These variations in compressing values are considered within the scope of this invention, allowing for adaptability and customization in diverse applications.

[0028] One exemplary type of compressor that can be employed in a hydrogen refueling station is the reciprocating piston compressor. This type of compressor operates by utilizing one or more pistons driven by a crankshaft, which compresses the hydrogen gas in a cylinder. The reciprocating piston compressor is known for its high reliability and ability to achieve high pressures. Furthermore, this compressor can be designed with varying numbers of stages to suit different pressure requirements, thus offering versatility in application.

[0029] Another example is the diaphragm compressor. This compressor type uses a diaphragm, which moves back and forth to change the volume of the compression chamber and compress the gas. This kind of compressor has the advantage that it is oil-free, to maintain the purity of hydrogen. Additionally, the diaphragm compressor is less prone to leakage.

[0030] A rotary screw compressor is also a viable option for use in the trailer download system 1. This compressor uses two meshing helical screws, known as rotors, to compress the gas. Rotary screw compressors are highly efficient and are particularly suitable for continuous operation, which is a common requirement in hydrogen refueling stations.

[0031] In other embodiments, the compressors 214, 224, 234, 244 can be of centrifugal type, using a rotating disk or impeller to impart kinetic energy to the gas, which is then converted into pressure. Centrifugal compressors are characterized by their smooth flow, high flow capacity, and relatively low maintenance requirements.

[0032] The distribution assembly 4 comprises a distribution pipeline 41. The distribution pipeline 41 is fluid-dynamic connected to the input connecting pipe 25, the output connecting pipe 26, and the inlets 211, 221, 231, 241 of each compressing stage 21, 22, 23, 24.

[0033] The control logic unit 3 is operatively connected to the control valves 42, the recycle valves 217, 227, and 237 and the valve units 215, 225, 235, 245. The controlvalve 42 and the valve unit 215 of the first compressing stages 21 are set and control the inlet pressure to the compressing stages 21, 22, 23, 24, while the recycle valves 217, 227 and 237 optimize the compressor ratio of each compressing stage 21, 22, 23, 24. Each valve unit 215, 225, 235, 245 is connected between the distribution pipeline 41 and its corresponding compressing stage 21, 22, 23, 24, and selectively distribute the gas from the trailer T to one or more compressing stages 21, 22, 23 and 24 depending on the gas pressure at the input connecting pipe 25 and the gas pressure required to be introduced into the refueling station storage R. This selective distribution system and the pressure control to compressor stages 21, 22, 23, 24 is key to optimizing the pressure increase process before the gas enters the refueling station storage R.

[0034] Each valve unit 215, 225, 235, 245 comprises a relevant valve 2151, 2251, 2351, 2451. Specifically, the first valve unit 215 comprises an adjustable electro-valve 2151, which is adjustable with it relevant actuator 2152. Also, the valve 2151 of the first valve unit 215 is connected between the trailer T and the gas inlet 211 of the first compressing stage 21. The other valve units 225, 235, 245 comprise a electro-valve 2251, 2351, 2451 of switch overtype, each one having a relevant actuator 2252, 2352, 2452. The operation of the first 215 and the other 225, 235, 245 valve units will be better explained below.

[0035] The control valve 42 also comprises an actuator 421, connected to the control logic unit 3, do that the latter can adjust the control valve 42, to adjust the gas flow passing through it.

[0036] The control logic unit 3 can be implemented in several ways.

[0037] In one embodiment, the control logic unit 3 can be implemented as a programmable microprocessor, which is a compact and highly efficient option. Microprocessors offer high processing speeds and can be customized for specific control tasks.

[0038] In another embodiment, the control logic unit 3 can be a PLC (Programmable Logic Controller). On the other hand, the PLC is specifically designed for industrial control applications, making it a robust and reliable choice. PLCs are known for their durability and resistance to harsh industrial environments, including vibrations, temperature variations, and electrical noise.

[0039] In some other embodiments, the control logic unit 3 can be integrated in a computer, thus offering the most flexibility and computational power among the alternatives.

[0040] The control logic unit 3 operates the control valves and switch-over valve units to manage the distribution of gas from the trailer T to the compressing stages 21, 22, 23, 24.

[0041] As mentioned the control valve 42, the recycle valves 217, 227, and 237 and the valve units 215, 225, 235, 245 are equipped with a control electro-valve. Specifically, each valve unit 215, 225, 235, 245 has a relevant 2151, 2251, 2351, 2451 and an actuator 2152, 2252, 2352, 2452, which are operatively connected to the control logic unit 3. The control logic unit 3 is configured and / or programmed to open, close or adjust the above control electro-valves, regulating the pressure and passage of gas from the distribution pipeline 41 to the respective compressors 214, 224, 234, 244.

[0042] The control electro-valves 2151, 2251, 2351, 2451 of the valve units 215, 225, 235, 245 can be solenoid valves or other types of electronically controlled valves, each operated by relevant actuators 2152, 2252, 2352, 2452, which could be electric motors, pneumatic actuators, or hydraulic actuators.

[0043] Each valve unit 215, 225, 235, 245 also comprises a pressure and / or temperature sensor 2153, 2253, 2353, 2453, which are positioned in relation to the pipeline where the control electro-valve is connected.

[0044] Also the distribution assembly 4 comprises a pressure and / or temperature sensor 43, arranged at the input connecting pipe 25. This sensor measure the pressure and the temperature of the gas in the trailer T. The function of the pressure and / or temperature sensor 43 will be better explained below. Various types of sensors, such as pressure transducers or piezoelectric sensors, can be employed to accurately measure the gas pressure.

[0045] To enhance the efficiency of the gas compression process, the trailer download system 1 comprises a series of intercoolers 213, 223, 233, 243, each connected to the gas outlet 212, 222, 232, 242 of each compressing stage 21, 22, 23, 24. The intercoolers 213, 223, 233, 243 reduce the temperature of the compressed gas, thereby improvingthe overall efficiency of the trailer download system 1.

[0046] Furthermore, each compressing stage 21, 22, 23, 24 is equipped with a relevant feedback line 216, 226, 236 and a recycle valve 217, 227, 237. These components are interconnected and are operatively connected to the control logic unit 3, allowing for fine-tuned control over the gas compression process.

[0047] Also, as mentioned, the first compressing unit 21 comprises the first valve unit 215 having an adjustable valve 2151. The other compressing stages 22, 23, 24 comprises the valve units 225, 235, 245 and the relevant switch-over valve has a switchover valve 2251, 2351, 2451. Each valve 2151, 2251, 2351, 2451 of the valve units 215, 225, 235, 245 is connected at the gas inlet 211, 221, 231, 241 of the relevant compressing stage 21, 22, 23, 24. The check valves 228, 238, 248 are arranged to prevent the back flow of the compressed gas passing from a compressing stage 22, 23, 24 to the following.

[0048] This configuration is designed to optimize the compression process based on the pressure levels of the hydrogen gas within the trailer.

[0049] In this alternative system, the bulk of the hydrogen, determined by the pressure within the trailer T, is initially directed to the higher compressing stages, e.g., 24, 23. This is managed by the main control valve 42 and the first valve unit 215, which ensures that a smaller proportion of the gas flow is directed through the lower compressing stages, i.e., 21 and 22.

[0050] Subsequently, as the pressure within the trailer T decreases to the rated inlet pressure for the lower compressing stages (e.g., 21 and 22), a transition occurs whereby the lower stage is fully engaged. This is facilitated by the stage recycle valves 217, 227, 237, , which recirculate a portion of the hydrogen back to the gas inlet 211, 221, 231, 241 of the previous compressor 214, 224, 234, 244, ensuring that the compressor operates efficiently without exceeding its design limits.

[0051] The valve units 225, 235, 245 namely all the valve units but for the first valve unit 215, which, as mentioned are of switch-over type) enable a seamless shift in the flow of hydrogen from one compressing stage 21, 22, 23, 24 to another (the following one) as the pressure within the trailer varies. These valve units 225, 235, 245 actuatein response to the pressure conditions to either open or close the passage of hydrogen gas, selectively operating the compressor / stages.

[0052] As mentioned above, the first valve unit 215 comprises an adjustable valve 2151 for allowing some of the gas from the trailer T to be introduced into the compressors 214, 224, 234, even if they are bypassed. In fact, in some embodiments the compressor 214, 224, 234, 244 are connected to a common shaft, therefore they have to be fed as better explained below.

[0053] In essence, the alternative architecture ensures that each compressing stage 21, 22, 23, 24 becomes fully engaged, or "full filled," only when the trailer’s pressure aligns with its rated inlet pressure, mirroring the operation of the trailer download system 1 but with distinct architectural components. This selective engagement of compressing stages 21, 22, 23, 24 based on trailer pressure maximizes the efficiency of the hydrogen compression process and minimizes energy consumption. It also allows for a more controlled and gradual compression cycle, thereby reducing wear on the overall trailer download system 1 and extending the operational lifespan of the refueling station’s equipment.

[0054] In another embodiment, referring to Fig. 2, of the trailer download system 1 each compressing stage 21, 22, 23, 24 comprises, instead of the feedback line, the recycle valves, and the on-off switch-over valves, a stepless actuator 219, 229, 239. These stepless actuators 219, 229, 239 are arranged for controlling the flow within each relevant compressor 214, 224, 234, 244.

[0055] A stepless actuator, also known as a continuous actuator, is a type of actuator that can move or adjust its output in a smooth, continuous range without any fixed increments or steps. This contrasts with traditional actuators, which move in predefined, discrete steps.

[0056] The stepless actuators 219, 229, 239 allow for very precise adjustments in the positioning or movement of mechanical components. Also, they enables a high degree of control over the mechanical system they are part of. Such actuators suffer less mechanical wear and tear then others.

[0057] The operation of the trailer download system 1 is as follows.

[0058] Specifically, the operation is carries out by a computer-implemented method 5, of which a flowchart is sown in Fig. 3. The operating method 5 comprises several steps. It begins with acquiring (step 51) the gas’s pressure by the pressure and / or temperature sensor 43, to ascertain the current pressure level of the gas within the trailer T. This step provides a baseline measurement from which adjustments to the gas pressure can be determined.

[0059] The method 5 comprises then the step of determining 52 how much the gas pressure needs to be increased before introducing it into a refueling station R. This step comprises calculating the difference between the current gas pressure and the required pressure level at the refueling station. This calculation is executed by the control logic unit 3, properly programmed, and possibly manually adjusted by an operator.

[0060] After determining the required pressure increase, the method involves the step 53, setting of the main control valve 42 and the adjustable valve 2151 of the valve unit 215 of the first compressing stages 21, and recycle valves 217, 227, 237 before opening any of the electro-valves 2251, 2351, 2451 of the valve units 225, 235, 245 by the relevant actuators 2252, 2352, 2452. The main valve 42 and the valve unit 215 serves as the primary control point for the gas pressure at inlet of each stage, and its early opening ensures a smoother and more controlled flow of gas throughout the system. While the recycle valves 217, 227, 237 control and optimize the stage compression ratio. Also, such centralized control allows a safety control of the system. In fact, the main valve 42 may be shut off in case of hydrogen leakage risk, being this gas highly inflammable.

[0061] Then the method comprises the step of opening 54 the switch-over valves of the valve units 225, 235, 245 (excluding the first valve unit 215), to distribute the gas to be compressed. In particular, in case the gas from the trailer T has to be compressed of a limited amount of bars, then only the last valve unit 245 is activated, namely the one closer to the refueling station R. Instead, if the pressure required is higher, then also other valve units 235 and 225, in sequence, starting from the valve unit 225, 235 closer to the valve unit 225, 235, 245 whose control electro-valve 2251, 2351, 2451 has been opened last. The function of this step is to control the flow of gas through the system, allowing it to reach the required pressure before entering the refueling station R.

[0062] This process continues until the sum of the pressure capabilities of the compressing stages 21, 22, 23, and 24 almost matches the required pressure increase as determined in step 52. Each compressing stage 21, 22, 23, 24 represents a different level of pressure amplification, and the method comprises coordinating these stages to collectively achieve the desired pressure level.

[0063] As mentioned, the method 5 is executed by the control logic unit 3, which is responsible for processing all sensor inputs, setting the pressures, executing the control algorithms, and activating the actuators and valves in the correct sequence to achieve the desired outcomes.ADVANTAGES

[0064] The trailer unloading system according to the present disclosure offers a compression package that is more energy-efficient than existing solutions. By optimizing the flow of hydrogen to the compressing stages based on real-time trailer pressure, the solution avoids the superfluous step of decompressing and subsequently recompressing hydrogen. This targeted approach to hydrogen flow reduces energy consumption, leading to a system that necessitates less power for operation compared to conventional systems lacking this innovative design.

[0065] From a customer standpoint, one of the advantages of this disclosure is the reduction in Operating Expense (OpEx) costs for hydrogen refueling stations that utilize trailers as their hydrogen source. The system’s design minimizes the amount of energy required for unloading hydrogen, thereby directly lowering the costs associated with energy consumption. The efficient use of energy translates into financial savings, making the operation of hydrogen refueling stations more economical over the long term.

[0066] By curtailing energy demand, the invention also contributes to the sustainability goals of hydrogen refueling stations. Lower energy consumption means a smaller carbon footprint, aligning with broader environmental objectives and potentially qualifying station operators for incentives related to energy conservation and sustainability.

[0067] The trailer download system according to the present disclosure can provide hydrogen refueling stations with a competitive edge in the market.

[0068] While aspects of the invention have been described in terms of various specific embodiments, it will be apparent to those of ordinary skill in the art that many modifications, changes, and omissions are possible without departing form the spirt and scope of the claims. In addition, unless specified otherwise herein, the order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments.

[0069] Reference has been made in detail to embodiments of the disclosure, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the disclosure, not limitation of the disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the disclosure. Reference throughout the specification to "one embodiment" or "an embodiment" or “some embodiments” means that the particular feature, structure or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrase "in one embodiment" or "in an embodiment" or "in some embodiments" in various places throughout the specification is not necessarily referring to the same embodiment(s). Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.

[0070] When elements of various embodiments are introduced, the articles “a”, “an”, “the”, and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including”, and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0071] The subject matter described herein can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structural means disclosed in this specification and structural equivalents thereof, or in combinations of them. The subject matter described herein can be implemented as one or more computer program products, such as one or more computer programs tangibly embodied in an information carrier (e.g., in a machine-readable storage device), or embodied in a propagated signal, for execution by, or to control the operation of, data processing apparatus (e.g., a programmable processor, a computer, or multiple com-puters). A computer program (also known as a program, software, software application, or code) can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file. A program can be stored in a portion of a file that holds other programs or data, in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub-programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network.

[0072] The processes and logic flows described in this specification, including the method steps of the subject matter described herein, can be performed by one or more programmable processors executing one or more computer programs to perform functions of the subject matter described herein by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus of the subject matter described herein can be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit).

[0073] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only memory, or a random access memory, or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. Information carriers suitable for embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, (e.g., EPROM, EEPROM, and flash memory devices); magnetic disks, (e.g., internal hard disks or removable disks); magneto-optical disks; and optical disks (e.g., CD and DVD disks). The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0074] To provide for interaction with a user, the subject matter described herein can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user and a keyboard and a pointing device, (e.g., a mouse or a trackball), by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well. For example, feedback provided to the user can be any form of sensory feedback, (e.g., visual feedback, auditory feedback, or tactile feedback), and input from the user can be received in any form, including acoustic, speech, or tactile input.

[0075] The techniques described herein can be implemented using one or more modules. As used herein, the term “module” refers to computing software, firmware, hardware, and / or various combinations thereof. At a minimum, however, modules are not to be interpreted as software that is not implemented on hardware, firmware, or recorded on a non-transitory processor readable recordable storage medium (i.e., modules are not software per se). Indeed “module” is to be interpreted to always include at least some physical, non-transitory hardware such as a part of a processor or computer. Two different modules can share the same physical hardware (e.g., two different modules can use the same processor and network interface). The modules described herein can be combined, integrated, separated, and / or duplicated to support various applications. Also, a function described herein as being performed at a particular module can be performed at one or more other modules and / or by one or more other devices instead of or in addition to the function performed at the particular module. Further, the modules can be implemented across multiple devices and / or other components local or remote to one another. Additionally, the modules can be moved from one device and added to another device, and / or can be included in both devices.

[0076] The subj ect matter described herein can be implemented in a computing system that includes a back-end component (e.g., a data server), a middleware component (e.g., an application server), or a front-end component (e.g., a client computer having a graphical user interface or a web browser through which a user can interact with an implementation of the subject matter described herein), or any combination of such back-end, middleware, and front-end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a com-munication network. Examples of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), e.g., the Internet.

Claims

Trailer Download System for Gas Refueling Stations, particularly for Hydrogen, and Operating Method thereofCLAIMS1. A trailer download system (1) configured to perform a pressure increase of a gas, particularly hydrogen gas, comprising: a gas compressing unit (2), having an input connecting pipe (25), connectable to a trailer (T), an output connecting pipe (26), connectable to a refueling station (R), and a plurality of compressing stages (21, 22, 23, 24), each one having a compressor (214, 224, 234, 244) for compressing the gas, a gas inlet (211, 221, 231, 241), for the gas entrance to be compressed by the compressor (214, 224, 234, 244), and a gas outlet (212, 222, 232, 242), from which the compressed gas comes out from the compressor (21, 22, 23, 24), and wherein the compressing stages (21, 22, 23, 24) are arranged in series, characterized in that the trailer download system (1) comprises a distribution assembly (4) comprising a distribution pipeline (41), fluid-dynamically connecting the input connecting pipe (25), the output connecting pipe (26), and the inlets (211, 221, 231, 241) of each one of the compressing stages (21, 22, 23, 24), wherein the fluid-dynamic connection of the distribution assembly (4) with the inlets (211, 221, 231, 241) is selectable, to distribute the gas from the trailer (T) to one or more compressing stage (21, 22, 23, 24), to increase its pressure before introducing it into the refueling station (R), depending on the pressure of the gas at the input connecting pipe (25).

2. The trailer download system (1) according to claim 1, comprising a control logic unit (3), wherein the distribution pipeline (41) is connected to each of the compressing stage (21, 22, 23, 24) comprises a valve unit (215, 225, 235, 245), connected betweenthe distribution pipeline (41) and the gas inlet (211, 221, 231, 241) of a relevant compressing stage (21, 22, 23, 24), wherein the control logic unit (3) is connected to each of the valve unit (215, 225, 235, 245), so that the control logic unit (3) opens the valve units (215, 225, 235, 245) to distribute the gas from the trailer (T) to one or more compressing stage (21, 22, 23, 24), to increase its pressure before introducing it into the refueling station (R).

3. The trailer download system (1) according to the preceding claim, wherein each valve unit (215, 225, 235, 245) comprises: an control electro-valve (2151, 2251, 2351, 2451); and an actuator (2152, 2252, 2352, 2452), connected to the control logic unit (3) and operatively connected to the control electro-valve (2151, 2251, 2351, 2451), wherein control logic unit (3) is configured to open or close the control electro-valve (2151, 2251, 2351, 2451), for allowing the passage of the gas from the distribution pipeline (41) to a relevant compressor (214, 224, 234, 244).

4. The trailer download system (1) according to any one of claims 2 or3, wherein one of the control electro-valve (2151) of one of the valve unit (215) is of adjustable type and is connected between the trailer (T) and the inlet gas inlet (211) of the relevant compressor (214), and wherein the other control electro-valves (2251, 2351, 2451) of one of the valve units (215, 225, 235) are of switch-over type.

5. The trailer download system (1) according to anyone of claims 3 or4, wherein each valve unit (215, 225, 235, 245) comprises a pressure and / or temperature sensor (2153, 2253, 2353, 2453), connected in correspondence to the pipeline where the control electro-valve (2151, 2251, 2351, 2451) is connected.

6. The trailer download system (1) according to any one of the preceding claims, wherein the distribution assembly (4) comprises a main control valve (42), connected to the trailer (T), and a pressure and / or temperature sensor (43), connected at the input connecting pipe (25), to measure the pressure and / or temperature of the gas in the trailer (T),wherein the main control valve (42) and the valve unit (215) allow the distribution of the gas from the trailer (T).

7. The trailer download system (1) according to any one of the preceding claims, comprising a plurality of intercoolers (213, 223, 233, 243), each one connected to the gas outlet (212, 222, 232, 242) of each compressing stage (21, 22, 23, 24).

8. The trailer download system (1) according to any one of the preceding claims, wherein each compressing stage (21, 22, 23, 24) comprises: a recycle line (216, 226, 236), connecting the gas outlet (212, 222, 232, 242) and the gas inlet (211, 221, 231, 241) the relevant compressing stage (21, 22, 23, 24); and a recycle valve (217, 227, 237, 247), arranged on a relevant recycle line (216, 226, 236, 246), wherein each recycle valve (217, 227, 237, 247) is operatively connected to the control logic unit (3); and a check valve (228, 238, 248) connected at the gas inlet (211, 221, 231, 241) of the relevant compressing stage (21, 22, 23, 24), to prevent the back flow of the compressed gas passing from a compressing stage (21, 22, 23, 24) to the following; wherein the control logic unit (3) is configured to control through the recycle valves (217, 227, 237, 247) the operating pressure of the compressing stages (21, 22, 23, 24).

9. The trailer download system (1) according to any one of claims 1-7, wherein each compressing stage (21, 22, 23, 24) comprises a stepless actuator (219, 229, 239) for controlling the flow of the relevant compressor (214, 224, 234).

10. Computer implemented method (5) of operation of a trailer download system (1) according to any one of the preceding claims, when depending on claims 3, comprising the steps of: acquiring (51) the pressure of the gas; determining (52) how much the gas pressure needs to be increased before introducing it into a refueling station (R); and opening (54) the control electro-valve (2451) of the last valve unit (245) closeto the refueling unit station (R) and, in sequence, the other control electro-valves (2251, 2351), starting from the valve unit (225, 235) closer to the valve unit (225, 235, 245) whose control electro-valve (2351, 2451) has been opened for last, until the sum of the pressure capabilities of the compressing stages (21, 22, 23, 24) almost matches the required pressure increase as determined in step (52).

11. The method (5) according to the preceding claim, when depending on claim 6, comprising, after the determining (52) step, the step of opening (53) the main control valves (42) before opening any of the control electro-valves (2251, 2351, 2451) of the valve unit (215, 225, 235, 245) by the relevant actuators (2152, 2252, 2352, 2452).

12. The method (5) according to any one of claim 10 or 11, when depending on claim 6, wherein the pressure of the gas is acquired (51) by the pressure and / or temperature sensor (43).

13. The method (5) according to any one of claim 10 - 12, wherein the method (5) is executed by the control logic unit (3).

Images