WO2016113120A1

WO2016113120A1 - Fluid energy machine, method for generating a fluid-volume flow and/or for compressing a fluid, and method for refuelling a vehicle

Info

Publication number: WO2016113120A1
Application number: PCT/EP2016/000014
Authority: WO
Inventors: Wilfried-Henning Reese; Tobias Kederer; Martin BRÜCKLMEIER; Simon Schäfer; Michael WESTERMEIER
Original assignee: Linde Aktiengesellschaft
Priority date: 2015-01-13
Filing date: 2016-01-07
Publication date: 2016-07-21
Also published as: CN107208613A; US20180010591A1; EP3245401A1; JP2018502253A; KR20170103943A

Abstract

The invention relates to a fluid energy machine and a method for generating a fluid-volume flow and for compressing a fluid by means of the fluid energy machine according to the invention. The invention also relates to a method for refuelling a vehicle with a fluid using the method according to the invention for generating a fluid-volume flow and for compressing a fluid, and to the use of a fluid energy machine according to the invention for refuelling a motor vehicle. The fluid energy machine comprises a crank drive (20) and a drive device (10) that is mechanically connected to the crank drive (20), by means of which drive device a torque can be introduced into the crank drive (20), as well as a piston-cylinder unit (30), the piston (32) of which is mechanically connected to the crank drive (20). The drive device (10) comprises two electric motors (50, 60), the respective output members (51, 61) of which are mechanically connected to the crank drive (20).

Description

description

Fluid energy machine, method for generating a fluid volume flow and / or for compressing a fluid and method for refueling a vehicle

The present invention relates to a fluid energy machine and to a method for generating a fluid volume flow and for compressing a fluid by means of the fluid energy machine according to the invention. Furthermore, the present invention relates to a method for refueling a vehicle with a fluid below

Application of the method according to the invention for generating a fluid volume flow and for compressing a fluid, as well as the use of a fluid energy machine according to the invention for refueling a motor vehicle.

For fueling facilities such as motor vehicles with hydrogen, which may be present in liquid form, so-called cryopumps are known, which are suitable to promote a fluid in the low temperature range. From DE102007035616A1 a pump is known, which is designed in particular for cryogenic media. This pump comprises a piston-cylinder unit which is adapted to convey and / or compress very cold fluids, such as hydrogen. Such pumps are usually operated with a hydraulic drive. Other conventional cryogenic pumping devices comprise a rotary drive instead of the hydraulic drive, in which case in particular the connection of an electric motor to a crank drive, which in turn is coupled to the piston of the piston-cylinder unit, has proven itself.

The hydraulic drive for the cryogenic pumping device usually requires a relatively large volume for housing additional units and a cooling device and a reservoir for the hydraulic fluid. Furthermore, a pump device with hydraulic drive in the installation and maintenance as well as for the measuring equipment to be installed for measuring distance in the hydraulic cylinder is relatively expensive. Usually, a linear displacement measuring system is to be arranged for this purpose. In order to avoid impermissible peak values of the volume flow to be generated, a sine-like acceleration curve of the piston is provided in the pump device adjust. When using a hydraulic drive device is the

Realization of a corresponding acceleration course associated with increased effort in terms of the necessary regulation and the control technology to be installed for this purpose. Furthermore, can be with hydraulic

Drive devices usually no longer realize strokes of the piston-cylinder unit as having a frequency of about 2 Hz.

In the embodiment variant with electromotive drive in combination with a crank mechanism limit the maximum, frequency-dependent nominal torques of commercial electric motors, the maximum capacity of the pumping device in terms of achievable flow rate and the achievable delivery pressure. When aspiring high flow rate and high delivery pressure corresponding frequencies of the strokes and forces or moments are applied by the electric motor to the crank mechanism. This means that corresponding opposing forces acting on the electric motor or on its storage and / or on the storage of a torque-transmitting machine element between the electric motor and the crank mechanism. The stability of the bearings is to be adapted if they are not to be exposed to appropriate wear, which is particularly noticeable when the output member of the electric motor is arranged substantially coaxially to the axis of rotation of the crank mechanism and is firmly connected to this crank mechanism.

The invention is therefore based on the object to provide a fluid energy machine and a method for generating a fluid volume flow and / or for the compression of a fluid with which in a simple, inexpensive and reliable and low-maintenance manner, a fluid such as gaseous hydrogen , Compressible, and a fluid, which here may be gaseous or liquid hydrogen, is conveyed. Other aspects of the invention

The underlying object is to provide a method for refueling a vehicle with a fluid as well as a use of the fluid energy machine according to the invention.

To achieve the object, a fluid energy machine according to claim 1 and a method for generating a fluid volume flow and / or for compressing a fluid according to claim 9 are provided. Advantageous embodiments of Fluid energy machine according to the invention are specified in the subclaims 1 to 8.

The fluid energy machine according to the invention comprises a crank drive and a drive device mechanically connected to the crank drive, with which a torque can be introduced into the crank drive. Furthermore, the fluid energy machine comprises a piston-cylinder unit whose piston is mechanically connected to the crank mechanism. It is inventively provided that the drive device comprises two electric motors whose respective output members are mechanically connected to the crank mechanism. Furthermore, it is provided that the piston-cylinder unit comprises only one piston and only one cylinder. The electric motors, hereinafter also referred to as motors for short, are rotatory motors, whereby the arrangement of more than two motors should not be excluded. The drive device thus comprises at least two motors. The torques of these engines or the

Drive means are applied to the crank mechanism, in particular on the crank, so as to actuate the crank mechanism and to realize a displacement of the piston of the piston-cylinder unit. In this case, the respective torque of a motor on the output member, such as at the shaft journal removed. The mechanical connection of the piston with the crank mechanism is realized in that the piston is mechanically connected to the connecting rod or coupling of the crank mechanism.

The crank mechanism preferably comprises only one crank and a coupling or connecting rod connected thereto, wherein the at least two motors arranged according to the invention apply their respective torque to this one crank.

In an alternative embodiment, two parallel cranks and coupling are present, so that each of the two motors acts on a respective crank drive. The

Crank drives are connected to the piston.

The fluid energy machine according to the invention is a cryogenic pump, for the purpose of generating a fluid volume flow and for the purpose of compressing a fluid. With this pump or this compressor can be a volume flow of liquid or gaseous hydrogen generate and the compression gaseous

Realize hydrogen. In one embodiment of the invention is the

Fluid energy machine set up so that the fluid to a pressure of 50 to 1000 bar, in particular to 350 to 500 bar or 700 bar can be compressed. Preferably, all inventively arranged motors are electric motors, but also the application of hydraulic motors should not be excluded.

The mechanical coupling of the motors to the crank mechanism is preferably realized on the crank of the crank mechanism, so that the respective engine torque is introduced into the crank. This crank can also be configured as an eccentric disc. The mechanical connection of the two motors to the crank can in particular be realized on both sides of the plane of movement of the crank of the crank mechanism, for

Example by two parallel eccentric discs, each forming a crank, which are connected to a coupling or a connecting rod. In this case, shafts between the motors and the crank mechanism for transmitting the torque are arranged coaxially.

An advantage of the fluid energy machine according to the invention is that it operates despite slow speeds of the shaft from 1 to 600 revolutions per minute (rpm) and still can achieve the necessary high pressures. Despite the slow speeds, a high torque in the range of 1000 to 4000 Nm can be achieved via the electric motors. The force exerted on the piston rod is 20 to 15 kN. In a first embodiment variant of the fluid energy machine according to the invention, the output member of at least one electric motor is coupled by means of a shaft directly to the crank of the crank mechanism. That is, for example, the motor journal of an engine is connected to a shaft which is mechanically connected directly to the crank.

In a further embodiment variant of the invention

Fluid energy machine is provided that between a driven member of at least one electric motor and the crank of the crank mechanism, a transmission, in particular a spur gear, for over or reduction of the torque generated by the electric motor is arranged. It is in this embodiment variant a

symmetrical arrangement preferred, so that in each case a gear is connected to both motors, which in turn is connected to the crank mechanism. Preferably, the crank mechanism comprises two drive shafts, so that in each case a transmission is arranged between a motor and a drive shaft. It should not be excluded the embodiment of the invention that one of the motors directly with the Crank drive is mechanically connected and the other or another motor indirectly, namely via a transmission, is connected to the crank mechanism.

Preferably, the crank mechanism should comprise a connecting rod which is mechanically connected to the piston of the piston-cylinder unit, such as via a joint. This connecting rod to be designated as a connecting rod is preferably pivotally connected to the piston and also pivotally connected to the crank.

Through the connection of two motors to the crank mechanism a symmetrical load and a distribution of the counter-forces or counter moments on the two motors or their drive shafts is achieved, which reduces the overall load and / or wear on the drive device or the crank mechanism can be. The bearings can be dimensioned correspondingly smaller, or the waves can be run with a smaller diameter.

In a preferred embodiment of the fluid energy machine, the shaft

ball bearings. This is made possible, among other things, by the low speeds. The entire fluid energy machine has a relatively low volume requirement.

In addition, conventional, commercially available electric motors with a

comparable low rated torque or low speed also for the realization of higher pressure and flow rates, as e.g. at a hydrogen refueling station. In the method for using a fluid energy machine according to the invention, for generating a hydrogen volume flow and for the compression of

Hydrogen, the liquid to be transported and compressed to be provided in liquid state, wherein the hydrogen is supplied to the piston-cylinder unit and the electric motors of the fluid energy machine are operated, so that the piston of the piston-cylinder unit is displaced and so on

Hydrogen flow generated and the hydrogen is compressed.

The inventive method is advantageously for refueling a

Vehicle used with liquid or gaseous hydrogen. In this case, either liquefied hydrogen is conveyed into a vehicle to be refueled, wherein only a volume flow is generated, or even gaseous hydrogen, which in this process embodiment simultaneously generating a

Volumetric flow and compression of the gas can be done. Preferably, the fluid energy machine is designed as a two-stage piston engine and in the first stage there is a pre-compression of the hydrogen and in the second stage, the compression to the system pressure.

In this case, the pressure is advantageously increased by 4 to 12 bar during precompression. The system pressure is preferably between 50 and 1000 bar, in particular between 350 and 500 bar.

The two stages are designed such that the precompression or precharge occurs when the piston is moved upwards, ie in the direction of the drive device. During the downward movement of the piston, so when the piston moves in the direction of the outlet, the pressure increase takes place from the first stage to the system pressure. The system pressure is limited by the maximum pump outlet pressure.

In a method according to the invention for use of the described

Fluidenergiemaschine the flow rate of hydrogen of the fluid energy machine on the frequency of the electric motors is set and this is between 0 and 250 kg / h and in particular between 30 to 200 kg / h.

The invention will be explained below with reference to the embodiments illustrated in the accompanying drawings.

It shows

1 shows a fluid energy machine according to the invention in a first embodiment, FIG. 2 shows a fluid energy machine according to the invention in a second embodiment. The embodiments shown in FIGS. 1 and 2 differ in that, in the variant according to FIG. 1, the motors are connected directly to the crank mechanism and in variant 2 according to FIG. 2 transmissions are provided between the motors and the crank mechanism. To describe the features present in both embodiments, reference is first made to both figures.

Both variants include a drive device 10, which is realized in the illustrated embodiments by a first motor 50 and a second motor 60. Both motors are designed as electric motors. To both motors 50, 60 is a respective speed sensor 53, 63 for adjusting the engine speed

connected. In both embodiments of the fluid energy machine, a crank drive 20 is provided, which has a crank 21, shown here with two eccentric disks, and a connecting rod 22 or coupling coupled to the crank 21 or to the two eccentric disks via a first joint 23. Furthermore, in both embodiments, a piston-cylinder unit 30 is provided which has a piston 32 which can be displaced there in a cylinder 31. The connecting rod 22 or coupling of the crank mechanism 20 is connected via a second joint 24 to the piston 32 of the piston-cylinder unit 30. Upon rotation of the crank 21 is a typical

Combination movement of rotation and translation of the connecting rod 22, which the piston 32, the piston rod is supported on both sides by bearings not shown here, each forming a sliding joint, absorb the transverse forces and the forced operation of the piston 32 in the cylinder 31 in the form of a piston stroke cause.

On the cylinder 31 of the piston-cylinder unit 30, an inlet device 33 for supplying a fluid 40 into the cylinder 31 and an outlet device 34 for discharging the cylinder 31 located in the possibly compressed fluid 40 is provided. The first motor 50 includes a first output member 51 and the second motor 60 includes a second output member 61. These output members 51, 61 are, for example, the shaft journals of the motors 50, 60. The respective output member 50, 60 is connected to a shaft, so that first output member 51 to a first shaft 52nd

is connected and the second output member 61 to a second shaft 62nd

connected.

In the embodiment shown in Fig. 1, the first shaft 52 and the second shaft 62 are connected directly to the crank 21 of the crank mechanism 20 so that a torque generated by the respective motor 50, 60 via the output member 51, 61 on the shaft arranged thereon 52, 62 is applied and from this shaft 52, 62 on the Crank 21 of the crank mechanism 20 is applied, so that by the crank mechanism 20, the described stroke movement of the piston 32 can be performed.

In the embodiment shown in FIG. 2, the first shaft 52 is connected to a first gear 70 having a first driving spur gear 71 on the first shaft 52 which meshes with a first driven spur gear 72 which is seated on a first output shaft 73. which is firmly connected to the crank 21 of the crank mechanism 20.

In a corresponding manner sits on the second shaft 62, a second driving spur gear 81 which meshes with a second driven spur gear 82, which in turn sits on a second output shaft 83 which is fixedly connected to the crank 21 of the crank mechanism 20. As a result, the torque and the rotational speed of the motors 50, 60 can be overridden or reduced in order to increase the torque to be generated by the crank mechanism 20 or to increase the frequency of the movement of the piston 32.

The invention is not limited to shown in Fig. 2 embodiment with symmetrical arrangement of gear members, but it may alternatively be provided to dispose different gear between the motors 50, 60 and the crank mechanism 20 and possibly also couplings between the respective engine 50, 60 and the crank drive 20 to order if necessary, a drive train on or disengage and thereby demand to provide a torque available.

LIST OF REFERENCE NUMBERS

Drive device 10

Crank drive 20

Crank 21

Connecting rod 22

First joint 23

Second joint 24

Piston-cylinder unit 30

Cylinder 31

Piston 32

Inlet device 33

Outlet device 34

Fluid 40

First engine 50

First output member 51

First wave 52

First speed sensor 53

Second motor 60

Second output member 61

Second wave 62

Second speed sensor 63

First transmission 70

First driving spur gear 71

First driven spur gear 72

First output shaft 73

Second gear 80

Second driving spur gear 81

Second driven spur gear 82

Second output shaft 83

Claims

claims

Fluid energy machine, comprising a crank drive (20) and a drive device (10) mechanically connected to the crank drive (20), with which a torque in the crank drive (20) can be introduced, and comprising a piston-cylinder unit (30), the piston (32) is mechanically connected to the crank mechanism (20),

characterized,

in that the drive device (10) comprises two electric motors (50, 60) whose respective output members (51, 61) are mechanically connected to the crank drive (20) and that the piston-cylinder unit (30) has only one piston (32) and comprises only one cylinder (31).

Fluid energy machine according to claim 1, characterized in that the fluid energy machine is a cryogenic pump, for the purpose of generating a fluid volume flow and for the purpose of compressing a fluid (40).

Fluid energy machine according to one of the preceding claims, characterized in that the fluid energy machine is arranged so that the fluid (40) can be compressed to a pressure of 50 to 1000 bar, in particular to 350 to 500 bar or 700 bar.

Fluid energy machine according to one of the preceding claims, characterized in that the mechanical coupling of the electric motors (50, 60) to the crank drive (20) is realized on the crank (21) of the crank drive (20), so that the engine torque into the crank (21 ) is initiated.

Fluid energy machine according to claim 4, characterized in that an output member (51, 61) of at least one electric motor (50,60) by means of a shaft (52,62) directly to the crank (21) of the crank mechanism (20) is coupled.

Fluid energy machine according to claim 4, characterized in that between a driven member (51, 61) of at least one electric motor (50,60) and the crank (21) of the crank mechanism (20), a transmission (70,80), in particular a Spur gear, for over or reduction of the torque generated by the electric motor (50,60) is arranged.

7. fluid energy machine according to one of the preceding claims, characterized

characterized in that the crank mechanism (20) comprises a connecting rod (22), and the piston

(32) is mechanically connected to the connecting rod (22).

8. fluid energy machine according to one of the preceding claims, characterized

characterized in that the shaft is ball-bearing.

9. A method of using a fluid energy machine according to claim 1 to 8, for generating a hydrogen volume flow and for the compression of

Hydrogen (40), being transported and compressed

Is provided in a liquid state, characterized in that the hydrogen (40) of the piston-cylinder unit (30) is supplied and the

Electric motors (50, 60) of the fluid energy machine are operated, so that the piston (32) of the piston-cylinder unit (30) is displaced and thus generates a hydrogen volume flow and the hydrogen (40) is compressed. 10. The method according to claim 9, characterized in that the compressed

Hydrogen is used to refuel a vehicle with liquid or gaseous hydrogen.

11. The method according to any one of claims 9 or 10, characterized in that the fluid energy machine is designed as a two-stage piston engine and in the first stage precompression of the hydrogen takes place and in the second stage, the compression to the system pressure.

12. The method according to claim 11, characterized in that in the

Pre-compression of the pressure is increased by 4 to 12 bar.

13. The method according to claim 11, characterized in that the system pressure is 50 to 1000 bar, in particular 350 to 500 bar or 700 bar.

14. The method according to at least one of claims 9 to 13, characterized

characterized in that the flow rate of hydrogen of the fluid energy machine is set by the frequency of the electric motors and this is between 0 and 250 kg / h, in particular between 30 to 200 kg / h.