Piston steam engine with thermolysis device for generating hydrogen, a combined heat and power plant comprising the piston steam engine, a computer-implemented method for controlling the piston steam engine and a control system for controlling the piston steam engine

Abstract

The present invention relates to a piston steam engine 1 comprising: at least one cylinder 10 which encloses a working chamber 15, a piston which is movable back and forth in the working chamber 15 between a top dead center and a bottom dead center along a central axis of the cylinder, a steam chamber 76 for providing fresh steam, an inlet valve 26 for controlling and / or regulating a fluid flow of the provided fresh steam which functions as the working fluid of the piston steam engine, wherein the working chamber 15 is enclosed over its circumference by a working chamber wall 14 which is inserted into the cylinder 10 or formed by it, and a thermolysis device 300 for generating hydrogen.The thermolysis device 300 has at least one cavity 310, which is arranged in the piston steam engine 1, in particular above the working chamber 15, such that a portion of the exhaust steam expelled after the power stroke can be collected therein and compressed to such an extent that the temperature of the compressed exhaust steam can be increased to 1200°C to 1500°C, in particular 1300°C to 1400°C, whereby a portion of the exhaust steam is decomposed into hydrogen by thermolysis. Furthermore, the present invention relates to a combined heat and power plant comprising the piston steam engine 1, a computer-implemented method for controlling and / or regulating a piston steam engine, as well as a computer program and a computer-readable storage medium.

Description

Technical area

[0001] The present disclosure relates to a piston steam engine with a thermolysis device for generating hydrogen, in particular to a piston steam engine that performs mechanical work using steam as its working fluid. More specifically, the present disclosure relates to a piston steam engine that is preferably used in electricity generation. Furthermore, the present disclosure relates to a combined heat and power plant comprising the aforementioned piston steam engine, a computer-implemented method for controlling the piston steam engine, a controller for controlling the piston steam engine, a computer program, and a computer-readable storage medium. background

[0002] Decentralized combined heat and power (CHP) plants have long been established as a beneficial alternative to the traditional combination of local heating and centralized power plants. CHP plants generate electrical energy and usable heat and are preferably operated on-site or near the heat sink. Combustion engines, such as diesel or gasoline engines, Stirling engines, steam engines, combustion turbines, or steam engines, can be used to power the power generator.

[0003] In CHP plants, the use of steam engines, especially piston steam engines, has recently gained interest. This is primarily due to the achievable high overall efficiency combined with low pollutant emissions and the virtually unlimited choice of liquid or solid fuel, such as wood, pellets, biogas, or biomass. This high efficiency can be achieved with steam pressures of 30 bar to 800 bar, preferably 30 to 500 bar, and steam temperatures of 300°C to 1000°C, preferably 400°C to 600°C. Due to these advantages, piston steam engines are also used in smaller biomass power generation plants, waste heat power plants, waste incineration plants, and thermal oxidizers.

[0004] In order to efficiently operate the piston steam engine, particularly the reciprocating piston of the piston steam engine, with a sufficient amount of steam at a correspondingly high pressure and temperature, it is necessary to supply the pressurized steam / live steam (working fluid) to the working chamber of the piston steam engine in a very short time and with precise timing in order to operate the reciprocating piston's working cycle without disruption (with smooth running). This requires, on the one hand, an inlet valve to optimally control and regulate the fluid flow of the live steam to the working chamber of the piston steam engine. On the other hand, it is necessary to provide the required amount of steam at optimal operating parameters (pressure and temperature).

[0005] In the prior art, a generally known steam generator is used to generate the required fresh steam (working fluid). An example of such a steam generator is described in European patent application number 22 172 048 5, which comprises: a housing, a flow channel through which a heat exchange fluid, preferably flue gas, can flow from an inlet of the flow channel to an outlet of the flow channel, wherein at least a portion of the flow channel is arranged in the housing as a first heat exchange element; at least one second heat exchange element arranged in the housing, through which water can flow to generate steam; a heat transfer medium arranged in the housing to transfer heat from the heat exchange fluid flowing through the flow channel to the water flowing through the second heat exchange element to generate steam, wherein the heat transfer medium is a salt bath.

[0006] By using a salt bath as a heat transfer medium, reliable operation can be ensured despite fluctuating energy content of the fuel mass of the steam generator, which, for example, uses biomass as an energy source.

[0007] Combined heat and power plants are often combined with other renewable energies, such as solar energy. However, solar energy can only be converted into electricity using relatively expensive technology and is only available to a limited extent or not at all, depending on the time of day, year, and weather. Furthermore, where the most energy is needed, unfavorable conditions usually prevail. Wind, on the other hand, can only be generated in a usable manner under suitable weather conditions and local circumstances, which means that there is neither continuity nor predictability. The disadvantages mentioned have been known for a long time. Therefore, intensive research into new energy sources has been carried out for some time. The use of hydrogen is particularly promising in this regard. The primary focus here is the direct use of hydrogen to power motor vehicles or to drive turbines, for example.for electricity generation and for direct electricity generation in fuel cells, which is also used to power motor vehicles or for heating systems in buildings.

[0008] Despite all of hydrogen's undeniable advantages, it has so far failed to establish itself as an energy source. This is primarily due to the complex production of hydrogen using conventional processes, which generally involve electrolysis. Conventional electrolysis, however, requires a significant amount of electrical energy. Therefore, the process is only viable and ecologically sound if electricity is available that is both inexpensive and pollutant- and CO2-free, i.e., produced using conventional renewable energies, which are subject to the disadvantages described above, which brings us back to the beginning of the problem.

[0009] Furthermore, as already mentioned, conventional renewable energy sources such as wind turbines, solar thermal systems, or photovoltaic systems are subject to strong fluctuations. This means that the available green electricity is subject to significant fluctuations and often has to be balanced with so-called gray electricity, which is generated, for example, from fossil fuels. The achievable energy prices on the electricity market are correspondingly volatile. Subject of the invention

[0010] Accordingly, the object of the invention is to provide a piston steam engine which is capable, on the one hand, of further increasing the efficiency of highly developed piston steam engines, as have been developed recently, and thus of pushing them to their physical limits, and, on the other hand, of producing hydrogen cost-effectively, free of pollutants and CO2. The aim is, on the one hand, to achieve maximum superheating of the working fluid (live steam) with minimal thermal load on the overall system (piston steam engine and components of the combined heat and power plant), and, on the other hand, to enable maximum flexibility of the overall system, whereby external conditions such as load changes, available live steam temperature and / or flue gas temperature and / or thermally stored energy in the salt bath can be responded to quickly and, in particular, while maintaining efficiency. Furthermore, depending on external conditions such as, for example,The maximum amount of hydrogen can be produced with the availability of green electricity. Finally, it should be possible to easily adjust the amount of electricity that can be generated to external factors such as the current electricity demand in the grid, the electricity price on the electricity market, and the availability of other green electricity sources.

[0011] This object is achieved by a piston steam engine according to claim 1 and a combined heat and power plant comprising the piston steam engine according to claim 19. The stated object is further achieved by a computer-implemented method according to claim 20, a controller according to claim 24, a computer program according to claim 25 and a computer-readable storage medium according to claim 26. Preferred developments of the invention are given in the dependent claims, wherein the subject matter of the claims relating to the piston steam engine can be used within the framework of the combined heat and power plant, the computer-implemented method, the controller, the computer program and the computer-readable storage medium and vice versa.

[0012] One of the basic ideas of the present disclosure is to provide a piston steam engine having a thermolysis device for generating hydrogen, wherein the thermolysis device has at least one cavity which is arranged in the piston steam engine, in particular above the working chamber, in such a way that a portion of the exhaust steam expelled or discharged after the working stroke, which may also contain live steam which is introduced into the working chamber after the working stroke, can be collected therein and compressed to such an extent that the temperature of the exhaust steam compressed therein can be increased to 1100°C to 1500°C, in particular 1200°C to 1400°C, whereby a portion of the exhaust steam is decomposed into hydrogen by thermolysis.

[0013] In this way, a piston steam engine can be provided which, in addition to its actual task of performing mechanical work, for example generating electrical power, can produce hydrogen by means of thermolysis using steam as the working fluid.

[0014] According to one aspect, a piston steam engine, which is preferably used for generating electrical power, comprises: at least one cylinder enclosing a working space, a piston moving back and forth in the working chamber between a top dead center and a bottom dead center along a central axis of the cylinder, a steam room for the provision of fresh steam, an inlet valve for controlling and / or regulating a fluid flow of the provided fresh steam which acts as the working fluid of the piston steam engine, wherein the working chamber is enclosed over its circumference by a working chamber wall inserted into the cylinder or formed by it, and a thermolysis device for producing hydrogen, wherein the thermolysis device has at least one cavity which is arranged in the piston steam engine, in particular above the working space, in such a way that a part of the exhaust steam expelled or discharged after the working stroke can be or is collected therein and compressed to such an extent that the temperature of the compressed exhaust steam can be or is increased to 1100°C to 1500°C, in particular 1200°C to 1400°C, whereby a part of the exhaust steam is decomposed into hydrogen by thermolysis, in particular catalytically induced thermolysis.

[0015] According to a further aspect of the present disclosure, the volume of the at least one cavity is selected such that the compression ratio of the exhaust steam compressed in the cavity can be adjusted to a value in the range from 1:30 to 1:50, wherein preferably the amount of exhaust steam compressed in the cavity can be adjusted in a range from 1% to 20%, preferably 5% to 10%, of the total exhaust steam (plus optionally live steam).

[0016] Furthermore, it is preferred that fresh steam is added to the exhaust steam; this can be injected into the working chamber shortly before TDC or directly into the at least one cavity.

[0017] Furthermore, it is preferred that approximately 70% to 90% of the compression volume be provided by the at least one cavity. In other words, at the time when the compression of the exhaust steam (optionally with live steam) is 100% complete, i.e., the piston is at top dead center (TDC), 70% to 90% of the remaining space (working space + cavity) is provided by the at least one cavity.

[0018] In this case, the thermolysis device preferably has a plurality of cavities, in particular 5 cavities, which are preferably provided in a chamber plate which delimits the working space at the top and which are preferably provided uniformly distributed in the circumferential direction of the working space wall.

[0019] Furthermore, it is advantageous if the at least one or the plurality of cavities has / have a shape such that the surface area of the cavity is minimal in relation to the volume of the cavity (A / V ratio), wherein preferably a surface area to volume ratio (A / V ratio) is in the range of 4.8 to 5.7, more preferably 4.83 to 5.2.

[0020] Furthermore, it is preferred that the at least one or the plurality of cavities are at least partially curved, more preferably spherical, in shape.

[0021] Furthermore, it is advantageous if a catalyst is provided in the at least one cavity to support the thermolysis, in particular to reduce the necessary starting temperature for the thermolysis. The catalyst preferably consists of nickel, platinum, or a platinum-iridium alloy. This enables so-called "catalytically induced thermolysis."

[0022] According to another aspect of the present disclosure, the catalyst is in the form of: - a wire coil made of a platinum-iridium alloy provided within the cavity, or - a cavity with a warped structure, the surface of the cavity being coated with a platinum-iridium alloy.

[0023] Furthermore, it is preferred if the piston steam engine comprises: a plurality of first exhaust steam outlet openings provided distributed in the circumferential direction of the working chamber wall, and a plurality of second exhaust steam outlet openings which are provided above the first exhaust steam outlet openings, preferably distributed in the circumferential direction, in the working chamber wall.

[0024] Furthermore, it is advantageous if the first exhaust steam outlet openings are opened and closed by the up and down movement of the piston, and / or the second exhaust steam outlet openings are opened and closed by a valve, in particular a mechanically, electrically, electronically, pneumatically or hydraulically operated valve or combinations thereof.

[0025] According to a further embodiment of the present disclosure, the second exhaust steam outlet openings are arranged in a first annular region which runs in the circumferential direction of the working chamber wall, in particular perpendicular to the central axis, and preferably has a width (B1) of 80 to 120 mm, preferably 50 to 80 mm, more preferably 20 to 40 mm, viewed in the direction of the central axis, wherein the second exhaust steam outlet openings preferably have a diameter of 10 to 20 mm.

[0026] Furthermore, it is preferred if the first annular region of the second exhaust steam outlet openings, in particular an imaginary center line of the region which runs perpendicular to the central axis, is arranged at a distance from the top dead center in the direction of the bottom dead center by 5% to 25%, preferably 10% to 20%, of the piston stroke.

[0027] Furthermore, it is advantageous if the piston steam engine is controlled such that the second exhaust steam outlet openings are opened, preferably by means of the valve, up to a range of 20° to 10°, in particular 15° to 10°, before the top dead center of the piston stroke, wherein the second exhaust steam outlet openings are preferably opened shortly before the bottom dead center UT, in particular in a range of 140° to 180° (40° to 0° before UT).

[0028] Furthermore, it is preferred that the piston steam engine has a superheater which is arranged between the inlet valve and the working chamber and is designed to superheat the fresh steam flowing through the inlet valve towards the working chamber.

[0029] Furthermore, it is preferred that the piston steam engine has a first water injection device, comprising an injection valve and at least one water injection opening, preferably a plurality of water injection openings, which is / are provided at the same height or above the first exhaust steam outlet openings, preferably distributed in the circumferential direction, in the working chamber wall, the water being preferably injected through a multi-hole nozzle.

[0030] According to a further aspect of the present disclosure, the piston steam engine comprises a second or further water injection device, comprising an injection valve and at least one water injection opening, preferably a plurality of water injection openings, wherein the injection opening(s) is / are arranged such that it opens directly or indirectly into the at least one cavity. Alternatively, only the second or further water injection device may be provided, since the functions of the two water injection devices are fundamentally different and not linked to one another.

[0031] In this way, it is possible to prevent recombination of the fission products hydrogen and oxygen directly in the area in which the thermolysis of the water vapor (exhaust steam + optionally live steam) into hydrogen and oxygen takes place at temperatures of 1100°C to 1500°C, preferably 1200° to 1400°C, by rapid cooling (in the microsecond range) of the temperature of the mixture within the at least one cavity.

[0032] Furthermore, the piston steam engine can have a microwave device arranged or configured such that the microwaves generated thereby penetrate the at least one cavity and thereby support thermolysis, in particular the splitting of water into hydrogen and oxygen. The frequency of the microwaves generated is preferably in a range from 2.45 GHz to 80 GHz, more preferably from 25 GHz to 50 GHz. The microwaves, in particular a microwave beam, are coupled in by means of a corresponding device.

[0033] If the piston steam engine is equipped with the thermolysis device according to the invention, the microwave device, and the second water injection device to prevent recombination, it is important that these three devices are optimally coordinated. Thus, if the temperature of the fresh steam drops, or other factors prevent the temperature required for (catalytic) thermolysis from being optimally reached, the microwave coupling can be amplified to still achieve sufficient thermolysis. Furthermore, it is necessary to optimally adjust the injection time of the water from the second water injection device to the compression and thus the time of (catalytic) thermolysis in order to achieve an optimal hydrogen production rate. This can preferably be achieved using characteristic map control.Furthermore, the water injection time is preferably adapted to the microwave coupling (power), also preferably by means of map control.

[0034] Furthermore, the piston steam engine may comprise a solid-state oscillator configured to operate the microwave device in the frequency range of 2.45 GHz to 80 GHz, wherein the frequency is preferably precisely adjustable in the range of one Hertz.

[0035] According to a further aspect of the present disclosure, the piston steam engine may comprise a hydrogen separation device configured to separate the hydrogen obtained from the oxygen also obtained, wherein the hydrogen separation device is preferably designed as a molecular sieve or another separation device.

[0036] Furthermore, it is advantageous if the piston steam engine has a radial turbine which is connected downstream of the piston steam engine and is driven by the exhaust steam of the piston steam engine, wherein the pressure of the exhaust steam released from the piston steam engine is preferably reduced from 0.4 bar to 1.0 bar to a pressure of 0.04 bar to 0.1 bar when flowing through the radial turbine.

[0037] Furthermore, it is preferred that the radial turbine is designed to drive a generator for generating electrical energy, wherein the exhaust steam of the piston steam engine expanded by the radial turbine is preferably fed to a downstream condenser which is designed to condense the exhaust steam.

[0038] In this case, it is particularly preferred that the piston steam engine has a spray cooler which is designed to inject water, in particular finely atomized water, into the expanded exhaust steam of the radial turbine in order to reduce the temperature of the exhaust steam and thus the pressure of the exhaust steam.

[0039] It is further preferred if the piston steam engine is provided with a crosshead which couples a piston rod connected to the piston and oscillating translationally to a connecting rod which oscillates translationally and rotationally (and at the same time also pivots out), wherein the crosshead is preferably mounted translationally via its own sliding bearing, in particular a sliding shoe.

[0040] It is further advantageous if the piston steam engine is provided with a hydrogen boost device comprising: a hydrogen injection device designed to inject (pure) hydrogen or a hydrogen-oxygen mixture (oxyhydrogen gas) into the working chamber of the piston steam engine, and optionally an oxygen injection device which is designed to inject or spray oxygen into the working chamber of the piston steam engine in order to control and / or monitor the ignition timing of the hydrogen or hydrogen-air mixture, whereby the ignition of the hydrogen or hydrogen-air mixture can take place by self-ignition or by an ignition device.

[0041] It is further preferred that the piston steam engine has a (further) microwave device which is arranged such that the microwaves which can be generated thereby penetrate the working space of the piston steam engine, in particular in an upper region, wherein the frequency of the microwaves which can be generated is in a range from 2.45 GHz to 80 GHz, preferably 25 GHz to 50 GHz, in order to actively control an ignition of the oxyhydrogen gas.

[0042] Furthermore, the present disclosure relates to a combined heat and power plant comprising: a steam generator and a piston steam engine according to one of the aspects described above, wherein the piston steam engine is coupled to a generator for generating electrical power.

[0043] Furthermore, the present disclosure relates to a computer-implemented method for controlling and / or regulating a piston steam engine, in particular a piston engine according to one of the aspects described above, wherein the piston steam engine comprises: at least one cylinder enclosing a working space, a piston moving back and forth in the working chamber between a top dead center and a bottom dead center along a central axis of the cylinder, a steam room for the provision of fresh steam, an inlet valve for controlling and / or regulating a fluid flow of the provided fresh steam which acts as the working fluid of the piston steam engine, wherein the working chamber is enclosed over its circumference by a working chamber wall inserted into the cylinder or formed by it, and a thermolysis device for producing hydrogen, the method comprising: - detecting at least one exhaust steam parameter of an exhaust steam emitted by the piston steam engine, wherein the at least one exhaust steam parameter is selected from the group comprising: exhaust steam temperature, exhaust steam pressure (vacuum) and humidity of the exhaust steam, - Determining an operating mode of the piston steam engine selected from the group comprising: balanced operation, increased power generation operation, maximum power generation operation and reduced power generation operation, - Determining an opening profile of a plurality of second exhaust steam outlet openings, which are provided above first exhaust steam outlet openings, preferably distributed in the circumferential direction, in the working chamber wall, depending on the detected at least one exhaust steam parameter in combination with the determined operating mode, and / or - Determining an injection profile of at least one water injection opening, preferably a plurality of water injection openings, which is preferably provided at the same height or above the first exhaust steam outlet openings in the working chamber wall, depending on the detected at least one exhaust steam parameter in combination with the determined operating mode, and / or - Controlling the thermolysis device, in particular its hydrogen production rate, as a function of the detected at least one evaporation parameter in combination with the determined operating mode.

[0044] Furthermore, it is preferred that at least one opening parameter of the opening profile of the second exhaust steam outlet openings is determined or ascertained as a function of the detected at least one steam parameter, selected from the group comprising: opening angle (e.g. in a range from 140° to 180° (40° to 0° before bottom dead center)), closing angle (e.g. in a range from 40° to 10° before top dead center), injection time (e.g. 30° before bottom dead center to 30° before top dead center), opening and closing speed and degree of opening and closing, and / or at least one injection parameter of the injection profile of the water injection openings is determined or ascertained as a function of the detected at least one exhaust steam parameter, selected from the group comprising: opening angle (e.g. in a range from 180° to 240° (0° to 60° after bottom dead center)), closing angle (e.g.in a range of 200° to 300° (20° to 120° after bottom dead center), opening duration or injection duration and quantity of water to be injected.

[0045] Furthermore, it is advantageous if the computer-implemented method further comprises: - Control of the thermolysis device, in particular its hydrogen production rate, depending on the determined operating mode, whereby: - in the case of increased power generation operation or maximum power generation operation, the thermolysis device is deactivated, and / or - in the case of balanced operation or minimized power generation operation, the thermolysis device is activated, wherein in the case of minimized power generation operation the hydrogen generation rate of the thermolysis device is preferably greater than in balanced operation.

[0046] Furthermore, it is preferred if, in the case of minimized power generation operation and / or balanced operation, the piston steam engine is operated with increased compression of the exhaust steam, preferably in the range of 1:30 to 1:50, thereby increasing the hydrogen production rate while simultaneously reducing the output power of the piston steam engine. It is also advantageous if, in balanced operation, the amount of exhaust steam compressed in the cavity is lower than in minimized power generation operation.

[0047] Furthermore, it is advantageous if the computer-implemented method further comprises: Activating a radial turbine connected downstream of the piston steam engine as a function of the detected at least one exhaust steam parameter, in particular the detected exhaust steam pressure, wherein the downstream radial turbine is preferably activated above a pressure of 1.0 bar, preferably above a pressure of 0.4 bar.

[0048] Furthermore, it is preferred if the computer-implemented method further comprises: Detection of at least one operating parameter of the piston steam engine selected from the group comprising: Fresh steam temperature, fresh steam pressure, fresh steam humidity, superheater temperature, heat exchange fluid temperature, flow rate of the heat exchange fluid, pressure of the heat exchange fluid, speed of the compressor stage, speed of the centrifugal pump and oil temperature of the piston steam engine, and Determining a target value of the at least one detected operating parameter as a function of the detected at least one evaporation parameter and / or at least one further detected operating parameter.

[0049] Furthermore, the present disclosure relates to a controller for controlling and / or regulating a steam engine, in particular for generating electrical current, comprising a control unit and means for carrying out the steps of the computer-implemented method described above.

[0050] The present disclosure also relates to a computer program, in particular an application software (app), comprising instructions which, when executed by a computer, cause the computer to carry out the above-described computer-implemented method for controlling and / or regulating a piston steam engine.

[0051] Furthermore, the present disclosure relates to a computer-readable storage medium comprising instructions which, when executed by a computer, cause the computer to carry out the above-described computer-implemented method for controlling and / or regulating a piston steam engine. Short description of the characters Fig. 1 shows a schematic diagram of a combined heat and power plant, Fig. Figure 2 shows a schematic sectional view of a steam engine according to an embodiment of the present invention, wherein the piston is at bottom dead center, Fig. 3 shows an enlarged partial view of the schematic sectional view of Fig. 2, to illustrate the arrangement of the thermolysis device according to the invention and the superheater, Fig. 4 shows a schematic diagram of a combined heat and power plant of another embodiment of the present invention, Fig. 5 shows an enlarged partial view of the schematic sectional view of Fig. 2, in order to further clarify the arrangement of the second exhaust steam outlet openings according to the invention and the thermolysis device according to the invention, and Fig. 6 shows a flow chart of a computer-implemented method for controlling and / or regulating a piston steam engine according to the invention. Detailed description of the preferred embodiments

[0052] Preferred embodiments of the present invention are described in detail below with reference to the accompanying figures. Further modifications of specific features mentioned in this context can each be combined individually to form further embodiments.

[0053] In the various figures, identical or corresponding elements are designated by the same or similar reference numerals.

[0054] Fig. Figure 1 shows a schematic diagram of a combined heat and power (CHP) plant. The CHP plant 200 shown consists of a steam generator 110, which is connected via a valve 180 to an inlet of a piston steam engine 1, which drives a generator 130 to generate electricity. For the fine sealing of the piston steam engine 1, it is necessary to supply it with oil. However, during operation of the piston steam engine 1, this oil mixes with the expanded steam (exhaust steam) and is released with it. For this reason, the expanded steam released by the piston steam engine 1 contains a small amount of oil.

[0055] The piston steam engine 1 is followed by a condenser 150 for condensing the expanded steam, which has a pressure of approximately 0.15 bar and a temperature of approximately 55°C when it leaves the piston steam engine 120.

[0056] The condensed steam is fed to or sucked into a condensate extraction pump (or circulation pump) 170, particularly a piston pump, via a water column 190, which increases the pressure of the condensed steam to approximately 0.25 bar. The oil is separated in the steam phase by a separator, and the separated oil is processed by a centrifuge.

[0057] Again Fig. 1 can also be removed, the separated or separated oil is led back to a crankshaft chamber of the piston steam engine or injected into the piston steam engine for fine sealing and the purified water is led to a feed water tank 160, which makes the treated or purified water available to the steam generator 110 again for steam generation, thus closing the circuit.

[0058] Fig. Figure 2 shows a schematic sectional view of a piston steam engine 1 according to an embodiment of the present invention. The piston steam engine 1 shown has a cylinder 10 having an upper end 11 and a lower end 12. At the lower end 12, the cylinder 10 is connected to a crankcase 20. A plurality of outlet openings 13 (first exhaust steam outlet openings) are provided circumferentially in the cylinder wall / working chamber wall 14 of the cylinder 10. The outlet openings 13 connect a cylinder chamber / working chamber 15 to an annular chamber 16 in order to discharge or remove used steam (exhaust steam) from the working chamber 15. The outlet openings 13 are arranged near a bottom dead center (UT) of a piston 30, which is located at bottom dead center (UT) in the view shown.

[0059] The piston 30 is translationally movable along a central axis CA of the cylinder 10 between the bottom dead center (UT) and a top dead center (TDC). The piston 30 is connected via a piston connecting rod or piston control rod (not shown) to a crankshaft (not shown), which is housed in the crankcase 20. The piston 30 has a sealing ring 31 at its lower end 32 and several sealing rings 31 at its upper end 33.

[0060] The piston steam engine 1 further comprises a cylinder head unit 40. The cylinder head unit 40 has a first housing body 41 and a second housing body 42. Furthermore, a steam chamber 76 (steam space) is provided in the first housing body 41, which communicates with the working chamber 15 via an opening. The opening (valve opening 28) can be opened and closed by means of a valve element 27 of an inlet valve 26, which has a shaft 53 guided translationally in a valve guide, whereby the inflow of live steam (superheated steam under high pressure) into the working chamber 15 can be controlled and / or regulated, wherein the live steam functions as the working fluid of the piston steam engine 1.Alternatively, the inlet valve 26 can also be designed as an electric, electronic, hydraulic, or pneumatic valve or combinations thereof, in particular an electro-hydraulic valve. This has the advantage that the injection elements of the valve remain cool, since they can be arranged in particular above the superheater described below.

[0061] Furthermore, the illustrated piston steam engine 1 has a superheater 60, which is arranged between the inlet valve 26 and the working chamber 15 and is designed to heat the fresh steam flowing through the inlet valve 26 toward the working chamber 15 and controlled and / or regulated by the inlet valve, thereby preferably superheating it into the supercritical high-temperature range. However, the superheater 60 shown is merely optional and serves to further optimize the efficiency of the piston steam engine.

[0062] Again Fig. 2, the superheater 60 has a tube heat exchanger formed from a plurality of individual pipes 62 that are evenly distributed around the central axis CA of the cylinder and arranged at a distance from one another. The individual pipes are bent around a bending axis Y, which is perpendicular to the central axis, with a bending angle of more than 360°, so that at least one loop is formed. In this way, the tube heat exchanger 61 forms a toroidal structure with the plurality of pipes 62. The individual pipes 62 are formed from a thick-walled steel tube and serve to supply the live steam, controlled and / or regulated from the steam chamber 76 by the inlet valve 26, to the working chamber 15. As the Fig. 2, the piston steam engine 1, in particular the superheater 60, has a heat exchange chamber 63 in which the pipes 62 of the toroidal tube heat exchanger 61 are arranged. The heat exchange chamber 63 has at least one inlet and at least one outlet via which the heat exchange chamber 63 can be supplied with a heat exchange fluid. In other words, during operation of the piston steam engine 1, a heat exchange fluid continuously flows through the heat exchange chamber 63, which flows around the pipes 62 of the tube heat exchanger 61 and thereby transfers heat to the live steam flowing through the pipes 62, thereby heating, in particular superheating, the live steam.

[0063] As the Fig. 2 further shows, the pipes 62 are aligned approximately vertically at the end facing the working chamber 15, whereby an opening 62A of the pipes 62 opens approximately vertically into the working chamber 15, whereby the kinetic energy of the live steam can be optimally utilized to drive the piston 30. The two ends of the pipes 62 are each welded into a holding element, in particular a holding plate, for fixation, wherein the ends of the pipes 62 facing away from the working chamber 15 taper conically towards the valve opening 28. As already described above, the superheater 60 can also be manufactured by 3D printing, in particular selective laser melting (SLM for short), in particular using Inconel (IN718) as the material. In this way, an optimized geometry of the superheater 60, in particular of the pipes 62, can be realized.

[0064] The heat exchange fluid flowing through the heat exchange chamber 63 can be a liquid metal selected from the group comprising: lead, sodium, sodium-potassium alloys (Nak), bismuth, and lead-bismuth eutectic, a salt bath selected from the group comprising: nitrate salt, in particular potassium-sodium nitrate or potassium-sodium-calcium nitrate, sodium chlorite, potassium chloride, sodium carbonate, potassium carbonate and sodium thiosulfate and a noble gas (inert gas), in particular helium, argon or xenon, or a noble gas mixture, preferably helium with nitrogen, or flue gas.

[0065] The use of a liquid metal or a salt bath has the advantage of allowing very large amounts of heat to be transferred at low flow velocities. However, the high temperatures of the liquid metals or salts place stringent demands on the flow-carrying components. When using gases, especially noble gases such as helium, the temperature resistance requirements of the flow-carrying components can be reduced, as helium protects the flow-carrying components, particularly against aging. This even makes it possible to increase the temperature to over 1000°C if desired.

[0066] If a gas, especially a noble gas, noble gas mixture or flue gas, is used as the heat exchange fluid, Fig. As shown in Figure 4, a compressor stage 70 can be connected upstream of the superheater 60. This compressor stage serves to charge the gas supplied to the piston steam engine 1, in particular to increase the gas pressure to 1 to 30 bar, in particular 5 to 20 bar, and to increase the gas flow velocity. In this case, the highest possible flow velocities in the range of 10 to 20 m / s, in some cases up to 50 m / s, are advantageous. The charging of the gas, in particular the increase in the flow velocity, is necessary in order to be able to transfer sufficient heat from the heat exchange fluid to the live steam flowing through the pipes 62.

[0067] The compressor stage can be designed as an electrically driven turbine or centrifugal pump, or as a turbocharger, and can, if desired, have guide vane adjustment. If thermal turbocharging is used, it can be driven by the exhaust steam of the reciprocating steam engine and / or by the exhaust gas (flue gas) of the steam generator 110 connected upstream of the reciprocating steam engine 1.

[0068] On the other hand, if a liquid metal or a salt bath is used as the heat exchange fluid, an agitator and / or a centrifugal pump and / or a magnetic field pump can be connected upstream and / or downstream of the superheater 60, which cause the heat exchange fluid to flow, in particular to flow it through the heat exchange chamber 63.

[0069] Furthermore, the piston steam engine 1 shown has a thermolysis device 300, which serves to generate hydrogen by means of thermolysis at times when there is a surplus of renewable energy, e.g., on extremely sunny days, and thus the achievable energy price is rather low. For this purpose, the thermolysis device 300 has, as shown in the Fig. 2, Fig. 3 and Fig. 5 shows at least one cavity 310, preferably a plurality of cavities, which are evenly distributed in the circumferential direction of the working chamber. In the embodiment shown, the device 300 has 5 cavities 310, with only 2 cavities being visible in section. The cavities 310 are open at the bottom and thus communicate with the working chamber 15. In this way, after the working cycle, a desired (predetermined) amount of exhaust steam, into which live steam can also be injected shortly before TDC, can be collected in the cavities and compressed to such an extent that the temperature of the compressed exhaust steam is increased to 1200°C to 1500°C, whereby at least part of the exhaust steam is decomposed or split into hydrogen and oxygen by thermolysis. For this purpose, the exhaust steam, which can also contain live steam, must be compressed to values in the range of 1:30 to 1:50, with approx.1% to 20% of the available exhaust steam is compressed in the cavities 310, the remaining exhaust steam is expelled as usual.

[0070] Again Fig. 3, the five cavities 310 are provided in the chamber plate 64 that defines the upper boundary of the working space 15, wherein the cavities 310 have an at least partially spherical contour. What cannot be seen from the figures is that the cavities 310 are provided with a catalyst 311 that serves to support the thermolysis, in particular to reduce the temperature required until the thermolysis starts. For this purpose, a platinum or platinum-iridium alloy is generally used, which can either be introduced into the cavities 310 as a wire coil, or the cavities 310 themselves, which preferably have a ridge structure, are coated with the platinum or platinum-iridium alloy. Nickel can also be used as a catalyst to bring about catalytically induced thermolysis; accordingly, Inconel is also a suitable material.

[0071] Again Fig. 5, the piston steam engine 1 according to the present embodiment has a (second) water injection device 320, which has an injection valve 321 and at least one water injection opening 322, preferably a plurality of water injection openings, wherein the injection opening 322 is arranged such that it opens directly into the at least one cavity 310. In this way, within microseconds after the compressed exhaust steam has been decomposed or split into hydrogen and oxygen by thermolysis, the temperature in the cavity can be ultra-rapidly reduced and the proportion of water vapor in the cavity can be increased by injecting pressurized water, whereby recombination of hydrogen and oxygen to form water can be suppressed.The water is injected at a pressure of 100 to 5000 bar, which allows for extremely small Sauter diameters of the injected droplets, resulting in very rapid evaporation and thus rapid cooling. The higher the water injection pressure to prevent recombination, the larger the surface area of the droplets (smaller Sauter diameter), and the faster the recombination is prevented.

[0072] Furthermore, the piston steam engine can be equipped with a microwave device (not shown in the figures) arranged such that the microwaves generated thereby penetrate the at least one cavity 310 and thereby support thermolysis, in particular the splitting of water into hydrogen. The frequency of the microwaves generated lies in a range from 2.45 GHz to 80 GHz, preferably 25 GHz to 50 GHz. In this case, a correspondingly designed device for coupling the microwaves is preferably used.

[0073] In this case, a solid-state oscillator (not shown in the figures) can also be provided, which is designed to operate the microwave device in the frequency range from 2.45 GHz to 80 GHz, wherein the frequency can preferably be precisely adjusted in a range of one Hertz.

[0074] Again Fig. As can also be seen from Figure 5, the piston steam engine shown has a hydrogen separation device 330 which is designed to separate the hydrogen obtained from the oxygen also obtained, wherein the hydrogen separation device 330 is preferably designed as a molecular sieve.

[0075] Furthermore, the piston steam engine 1 can optionally be equipped with a hydrogen boost device 340, comprising: a hydrogen injection device configured to inject hydrogen or a hydrogen-air mixture (oxyhydrogen gas) into the working chamber 15 of the piston steam engine 1 via injection openings 341. Additionally, an oxygen injection device (not shown) can be provided, configured to inject oxygen into the working chamber 15 of the piston steam engine 1 in order to control the ignition point of the hydrogen or hydrogen-air mixture, in particular to advance it. The hydrogen or hydrogen-air mixture can be ignited by auto-ignition or by an ignition device (not shown).

[0076] In addition to the first exhaust steam outlet openings 13 (outlet openings), a plurality of second exhaust steam outlet openings 18 are provided above the first exhaust steam outlet openings 13, distributed circumferentially in the working wall 14. The first exhaust steam outlet openings 13 are opened and closed by the up and down movement of the piston 30. The second exhaust steam outlet openings 18, on the other hand, are opened and closed by a valve (19), in particular a mechanically, electrically (magnetically), electronically, pneumatically, or hydraulically actuated valve, or combinations thereof. In this way, it is possible to change the opening and closing times of the valve 19 depending on the engine load and / or the status data of the reciprocating steam engine. In contrast to the first exhaust steam outlet openings 13, the second exhaust steam outlet openings 18 are optional and serve to further optimize the efficiency of the reciprocating steam engine 1.

[0077] Again Fig. 2, but in particular the Fig. 5, the second exhaust steam outlet openings 18 are arranged in a first annular region which runs in the circumferential direction of the working chamber wall 14 perpendicular to the central axis CA and, viewed in the direction of the central axis CA, has a width B1 of 80 to 120 mm, wherein the second exhaust steam outlet openings 18 have a diameter of 10 to 20 mm. Furthermore, the first annular region of the second exhaust steam outlet openings 18, in particular an imaginary center line of the region which runs perpendicular to the central axis CA, is arranged at a distance of 5% to 25% of the piston stroke from the top dead center TDC in the direction of the bottom dead center TDC.

[0078] Additionally or alternatively, as in Fig. 4, the piston steam engine 1 or the combined heat and power plant 200 may be equipped with a radial turbine 80 (steam turbine) connected downstream of the piston steam engine 1. The radial turbine 80 is driven by the exhaust steam of the piston steam engine 1, whereby the pressure of the exhaust steam released by the piston steam engine 1 is reduced from 0.4 bar to 1.0 bar as it flows through the radial turbine to a pressure of 0.04 bar to 0.1 bar. By installing the radial turbine in the exhaust steam line of the piston steam engine 1, a back pressure is created in the outlet of the piston steam engine 1, whereby the pressure of the released steam increases from approximately 0.15 bar to 0.5 bar. Fig. 4, the radial turbine 80 serves to drive a generator 130 to generate electrical energy, wherein the exhaust steam of the piston steam engine 1 expanded by the radial turbine is fed to a downstream condenser 150 for condensing the exhaust steam.

[0079] As the Fig. As also shown in Figure 4, the piston steam engine 1 or the combined heat and power plant 200 can be equipped with a spray cooler 90. The spray cooler serves to inject water into the expanded exhaust steam of the radial turbine in order to further lower the temperature of the exhaust steam and thus improve the vacuum. In other words, by injecting finely atomized water into the exhaust steam of the radial turbine, the temperature of the exhaust steam is lowered and thus the pressure is further reduced (increasing the vacuum), thereby increasing the power of the radial turbine and thus allowing more electrical power to be generated.

[0080] The radial turbine 80 is preferably provided in combination with the spray cooler 90, whereby the increased performance of the radial turbine 80 allows as much electricity and as little heat as possible to be produced in the summer months, since the heat demand is generally reduced.

[0081] The Fig. 2 and Fig. 4 further show that the piston steam engine 1 or the combined heat and power plant 200 can optionally be equipped with a (first) water injection device 100, which has an injection valve 101 and a plurality of water injection openings 102, wherein the water injection openings 102 are provided at the same height or above the first exhaust steam outlet openings 13, distributed in the circumferential direction in the working chamber wall 14. It is also conceivable to provide the injection openings in the upper region of the cylinder or the cylinder head.

[0082] Fig. 6 shows a flow chart of a computer-implemented method for controlling and / or regulating a piston steam engine 1 according to the invention. The computer-implemented method shown is used to carry out the process described above in connection with the Fig. 1 to 5 described piston steam engine. As the Fig. 6, the procedure comprises the following steps: Detection S10 of at least one exhaust steam parameter of an exhaust steam emitted by the piston steam engine 1, wherein the at least one exhaust steam parameter is selected from the group comprising: exhaust steam temperature, exhaust steam pressure (vacuum) and humidity of the exhaust steam, Determining S20 an operating mode of the piston steam engine, selected from the group comprising: balanced operation, increased power generation operation, maximum power generation operation and minimized power generation operation, Determining S30 an opening profile of a plurality of second exhaust steam outlet openings 18, which are provided above the first exhaust steam outlet openings 13, preferably distributed in the circumferential direction, in the working chamber wall 14, depending on the detected at least one exhaust steam parameter in combination with the determined operating mode, and / or Determining S40 an injection profile of a plurality of water injection openings 102, which are preferably provided at the same height or above the first exhaust steam outlet openings 13 in the working chamber wall 14, depending on the detected at least one exhaust steam parameter in combination with the determined operating mode, and / or Control S50 of the thermolysis device 300, in particular its hydrogen generation rate, as a function of the detected at least one evaporation parameter in combination with the determined operating mode.

[0083] Again Fig. 6, the computer-implemented method may optionally comprise the following additional steps: Determining or determining S60 at least one opening parameter of the opening profile of the second exhaust steam outlet openings 18 as a function of the detected at least one steam parameter, selected from the group comprising: Opening angle (e.g. in a range of 140° to 180° (40° to 0° before BDC)), closing angle (e.g. in a range of 20° to 10° before TDC), opening and closing speed and degree of opening and closing, and / or Determining or determining S70 at least one injection parameter of the injection profile of the water injection openings 102 as a function of the detected at least one evaporation parameter, selected from the group comprising: opening angle (e.g. in a range from 180° to 240° (0° to 60° after BDC)), closing angle (e.g. in a range from 200° to 300° (20° to 120° after BDC), opening duration or injection duration and quantity of water to be injected.

[0084] Furthermore, as in Fig. 6 shows that methods further comprise the step of: Activation S80 of a radial turbine 80 connected downstream of the piston steam engine 1 as a function of the detected at least one exhaust steam parameter, in particular the detected exhaust steam pressure, wherein the downstream radial turbine 80 is activated above a pressure of 1.0 bar, preferably above a pressure of 0.4 bar.

[0085] In the computer-implemented method according to the invention, it is further advantageous that the main injection of the fresh steam (high-pressure steam) is prioritized, and all other control loops are subordinate to the control of the fresh steam, in particular its injection.

[0086] From the foregoing description, those skilled in the art will recognize that various modifications and variations of the apparatus and method of the invention can be made without departing from the scope of the invention.

[0087] Furthermore, the invention has been described with reference to specific embodiments, which are intended only to facilitate understanding of the invention and are not intended to be limiting. Those skilled in the art will also readily recognize that many different combinations of the elements may be used to practice the present invention. Therefore, the scope of the invention is indicated by the following claims. List of reference symbols 1 piston steam engine 10 cylinders 13 first exhaust steam outlet openings 14 Workroom wall 15 work space 18 second steam outlet openings 19 Valve (control valve for second exhaust steam outlet openings) 26 Inlet valve 27 Valve body 28 Valve opening 29 Valve seat 30 pistons 60 superheaters 61 tube heat exchangers 62 pipes of the tube heat exchanger 62A opening 63 Heat exchange chamber 70 compressor stage 76 Steam room 80 radial turbine 90 spray coolers 100 (first) water injection device 101 Injector 102 water injection holes 110 steam generators 130 Generator 150 capacitor 300 Thermolysis device 310 cavity(ies) for thermolysis 320 (second) water injection device 321 Injector valve (of the water injection device) 322 injection opening(s) (of the water injection device) 330 Hydrogen separation device 340 Hydrogen Boost Facility 341 injection ports (hydrogen boost device) QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 22 172 048 5

[0005]

Claims

[1] Piston steam engine (1), preferably used for generating electric power, comprising: at least one cylinder (10) enclosing a working space (15), a piston (30) movable back and forth in the working chamber (15) between a top dead center (OT) and a bottom dead center (UT) along a central axis (CA) of the cylinder (10), a steam chamber (76) for providing fresh steam, an inlet valve (26) for controlling and / or regulating a fluid flow of the provided fresh steam which acts as the working fluid of the piston steam engine, wherein the working chamber (15) is enclosed over its circumference by a working chamber wall (14) inserted into the cylinder (10) or formed by the latter, and a thermolysis device (300) for producing hydrogen, wherein the thermolysis device (300) has at least one cavity (310) which is arranged in the piston steam engine (1), in particular above the working space (15), in such a way that a part of the exhaust steam expelled after the working stroke can be collected therein and compressed to such an extent that the temperature of the compressed exhaust steam can be increased to 1100°C to 1500°C, in particular 1200°C to 1400°C, whereby a part of the exhaust steam is decomposed into hydrogen by thermolysis. [2] Piston steam engine (1) according to claim 1, wherein the volume of the at least one cavity (310) is selected such that the compression ratio of the exhaust steam compressed in the cavity (310) can be adjusted to a value in the range from 1:30 to 1:50, wherein preferably the amount of exhaust steam compressed in the cavity (310) can be adjusted in a range from 1% to 20%, preferably 5% to 10%, of the total exhaust steam. [3] Piston steam engine (1) according to claim 1 or 2, wherein the thermolysis device (300) has a plurality of cavities (310), in particular 5 cavities (310), which are preferably provided in a chamber plate (64) delimiting the working space (15) at the top, which are preferably provided uniformly distributed in the circumferential direction of the working space wall (14). [4] Piston steam engine (1) according to one of the preceding claims, wherein the at least one or the plurality of cavities (310) has / have a shape such that the surface area of the cavity (310) is minimal in relation to the volume of the cavity (310) (A / V ratio) (preferably a surface area to volume ratio (A / V ratio) is in the range of 4.8 to 5.7, more preferably 4.83 to 5.2). [5] Piston steam engine (1) according to one of the preceding claims, wherein the at least one or the plurality of cavities (310) are at least partially curved, more preferably spherical, in shape. [6] Piston steam engine (1) according to one of the preceding claims, wherein a catalyst (311) is provided in the at least one cavity (310) to support the thermolysis, in particular to reduce the necessary starting temperature of the thermolysis, wherein the catalyst preferably consists of nickel, platinum or a platinum-iridium alloy. [7] Piston steam engine (1) according to claim 6, wherein the catalyst (311) is in the form of: - a wire coil made of a platinum-iridium alloy provided within the cavity (310), - a cavity (310) with a warped structure, wherein the surface of the cavity is coated with a platinum-iridium alloy. [8] Piston steam engine (1) according to one of the preceding claims, further comprising: a plurality of first exhaust steam outlet openings (13) which are provided distributed in the circumferential direction of the working chamber wall (14), and a plurality of second exhaust steam outlet openings (18) which are provided above the first exhaust steam outlet openings (13), preferably distributed in the circumferential direction, in the working chamber wall (14). [9] Piston steam engine (1) according to claim 7, wherein the first exhaust steam outlet openings (13) are opened and closed by the up and down movement of the piston (30), and / or the second exhaust steam outlet openings (18) are opened and closed by a valve (19), in particular a mechanically, electrically, electronically, pneumatically or hydraulically operated valve or combinations thereof. [10] Piston steam engine (1) according to claim 8 or 9, wherein the second exhaust steam outlet openings (18) are arranged in a first annular region which runs in the circumferential direction of the working chamber wall (14), in particular perpendicular to the central axis (CA), and preferably has a width (B1) of 80 to 120 mm, preferably 50 to 80 mm, more preferably 20 to 40 mm, viewed in the direction of the central axis (CA), wherein the second exhaust steam outlet openings (18) preferably have a diameter of 10 to 20 mm. [11] Piston steam engine (1) according to one of claims 7 to 10, wherein the piston steam engine (1) is controlled such that the second exhaust steam outlet openings (18) are closed (by means of the valve (19)) in a range of 0° to 20°, in particular 0° to 10°, after the bottom dead center (UT) of the piston stroke. [12] Piston steam engine (1) according to one of claims 1 to 11, further comprising a superheater (60) which is arranged between the inlet valve (26) and the working chamber (15) and is designed to superheat the fresh steam flowing in through the inlet valve (26) in the direction of the working chamber (15). [13] Piston steam engine (1) according to one of the preceding claims, further comprising: a first water injection device (100) comprising an injection valve (101) and at least one water injection opening, preferably a plurality of water injection openings (102), which is / are provided at the same height or above the first exhaust steam outlet openings (13), preferably distributed in the circumferential direction, in the work chamber wall (14). The water is preferably injected through a multi-hole nozzle. [General water injection device for controlling the work cycle] [14] Piston steam engine (1) according to one of the preceding claims, further comprising: a second water injection device (320) comprising an injection valve (321) and at least one water injection opening (322), preferably a plurality of water injection openings, wherein the injection opening(s) is arranged such that it opens directly or indirectly into the at least one cavity (310), wherein the water is preferably injected under a pressure of 100 bar to 5000 bar. [15] Piston steam engine (1) according to one of the preceding claims, further comprising: a microwave device arranged such that the microwaves that can be generated thereby penetrate the at least one cavity (310) and thereby support the thermolysis, in particular the splitting of water into hydrogen, wherein the frequency of the microwaves that can be generated is in a range from 2.45 GHz to 80 GHz, preferably 25 GHz to 50 GHz, and preferably a device for coupling the microwaves is provided. [16] Piston steam engine (1) according to claim 15, further comprising: a solid-state oscillator configured to operate the microwave device in the frequency range from 2.45 GHz to 80 GHz, wherein the frequency is preferably precisely adjustable within a range of one Hertz. [17] Piston steam engine (1) according to one of the preceding claims, further comprising a hydrogen separation device (330) which is designed to separate the hydrogen obtained from the oxygen also obtained, wherein the hydrogen separation device is preferably designed as a molecular sieve or another separation device. [18] Piston steam engine (1) according to one of the preceding claims, further comprising a hydrogen boost device (340) comprising: a hydrogen injection device which is designed to inject hydrogen or a hydrogen-oxygen mixture (oxyhydrogen gas) into the working chamber (15) of the piston steam engine (1), and optionally an oxygen injection device which is designed to inject oxygen into the working chamber (15) of the piston steam engine (1) in order to control the ignition point of the hydrogen or hydrogen-air mixture, whereby the ignition of the hydrogen or hydrogen-air mixture can take place by self-ignition or by an ignition device. [19] Combined heat and power plant (200), comprising: a steam generator (110), and a piston steam engine (1) according to one of the preceding claims 1 to 18, wherein the piston steam engine (1) is coupled to a generator (130) for generating electrical current. [20] Computer-implemented method for controlling and / or regulating a piston steam engine, in particular the piston steam engine (1) according to one of claims 1 to 18, comprising: at least one cylinder (10) enclosing a working space (15), a piston (30) movable back and forth in the working chamber (15) between a top dead center (OT) and a bottom dead center (UT) along a central axis (CA) of the cylinder (10), a steam chamber (76) for providing fresh steam, an inlet valve for controlling and / or regulating a fluid flow of the provided fresh steam which acts as the working fluid of the piston steam engine, wherein the working chamber (15) is enclosed over its circumference by a working chamber wall (14) inserted into the cylinder (10) or formed by the latter, and a thermolysis device (300) for producing hydrogen, the method comprising: - detecting at least one exhaust steam parameter of an exhaust steam emitted by the piston steam engine (1), wherein the at least one exhaust steam parameter is selected from the group comprising: exhaust steam temperature, exhaust steam pressure (vacuum) and humidity of the exhaust steam, - Determining an operating mode of the piston steam engine selected from the group comprising: balanced operation, increased power generation operation, maximum power generation operation and minimized power generation operation, - determining an opening profile of a plurality of second exhaust steam outlet openings (18) which are provided above first exhaust steam outlet openings (13), preferably distributed in the circumferential direction, in the working chamber wall (14), depending on the detected at least one exhaust steam parameter in combination with the determined operating mode, and / or - determining an injection profile of at least one water injection opening (102), which is preferably provided at the same height or above the first exhaust steam outlet openings (13) in the working chamber wall (14), as a function of the detected at least one exhaust steam parameter in combination with the determined operating mode, and / or - Controlling the thermolysis device (300), in particular its hydrogen generation rate, as a function of the detected at least one evaporation parameter in combination with the determined operating mode. [21] A computer-implemented method according to claim 20, wherein at least one opening parameter of the opening profile of the second exhaust steam outlet openings (18) is determined or ascertained as a function of the detected at least one steam parameter, selected from the group comprising: Opening angle (e.g. in a range of 140° to 180° (40° to 0° before BDC)), closing angle (e.g. in a range of 20° to 10° before TDC), opening and closing speed and degree of opening and closing, and / or at least one injection parameter of the injection profile of the water injection openings (102) is determined or ascertained as a function of the detected at least one evaporation parameter, selected from the group comprising: Opening angle (e.g. in a range of 180° to 240° (0° to 60° after BDC)), closing angle (e.g. in a range of 200° to 300° (20° to 120° after BDC), opening duration or injection duration and quantity of water to be injected. [22] A computer-implemented method according to claim 20 or 21, further comprising: - Control of the thermolysis device (300), in particular its hydrogen production rate, depending on the determined operating mode, wherein: - in the case of increased power generation operation or maximum power generation operation, the thermolysis device (300) is deactivated, - in the case of balanced operation or minimized power generation operation, the thermolysis device (300) is activated, wherein in the case of minimized power generation operation the hydrogen generation rate of the thermolysis device is preferably greater than in balanced operation. [23] A computer-implemented method according to claim 22, wherein in the case of: the minimized power generation operation and / or the balanced operation, the piston steam engine (1) is operated with increased compression of the exhaust steam, preferably in the range of 1:30 to 1:50, whereby the hydrogen generation rate is increased and at the same time the output power of the piston steam engine (1) is reduced, wherein preferably in balanced operation the amount of exhaust steam compressed in the cavity (310) is lower than in minimized power generation operation. [24] Control system for controlling and / or regulating a steam engine (1), in particular for generating electrical current, comprising a control unit and means for carrying out the steps of the method according to one of claims 20 to 23. [25] Computer program, in particular application software (app), comprising instructions which, when executed by a computer, cause the computer to execute the computer-implemented method for controlling and / or regulating a piston steam engine (1) according to one of the preceding claims 20 to 23. [26] Computer-readable storage medium comprising instructions which, when executed by a computer, cause the computer to execute the computer-implemented method for controlling and / or regulating a piston steam engine (1) according to one of the preceding claims 20 to 23.

Images