Reversible solid oxide cell system and method of controlling the same

Abstract

The application provides a reversible solid oxide battery system and a control method thereof, and relates to the field of new energy sources.The reversible solid oxide battery system comprises a fuel processing unit, an air processing unit and a reversible solid oxide battery unit.The reversible solid oxide battery unit is connected with an external load, and is used for converting electric energy and water into hydrogen and oxygen when the electric power of the external load is sufficient, and is used for converting hydrogen and oxygen into electric energy through an electrochemical reaction when the electric power of the external load is insufficient.The fuel processing unit is connected with a fuel side of the reversible solid oxide battery unit through a pipeline, and the air processing unit is connected with an air side of the reversible solid oxide battery unit through a pipeline.The application can flexibly adapt to different load requirements, and can improve the system efficiency.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and more specifically, to a reversible solid oxide battery system and its control method. Background Technology

[0002] Reversible solid oxide battery (RSOC) systems possess bidirectional operation capabilities, allowing them to both supply electricity in power generation mode and consume electrical energy through electrolysis, achieving flexible conversion between chemical and electrical energy. This characteristic effectively addresses the energy consumption issues arising from the intermittency and instability of renewable energy sources, as well as the flexibility adjustment challenges faced by new power systems. Therefore, they can be applied between renewable energy sources, the power grid, and the gas grid, serving as a hub for energy conversion.

[0003] However, existing reversible solid oxide battery systems are structurally complex and lack mode switching control design, resulting in relatively low overall efficiency. Summary of the Invention

[0004] The present invention aims to provide, for example, a reversible solid oxide battery system and its control method, which can flexibly adapt to changes in load and improve conversion efficiency.

[0005] The embodiments of the present invention can be implemented as follows:

[0006] In a first aspect, the present invention provides a reversible solid oxide battery system, the reversible solid oxide battery system comprising a fuel processing unit, an air processing unit, and a reversible solid oxide battery cell;

[0007] The reversible solid oxide battery cell is used to connect to an external load;

[0008] The fuel processing unit includes a hydrogen storage tank, a hydrogen pressure reducing valve, a first flow meter, a first mixer, a fuel preheater, a hydrogen compressor, a hydrogen condenser, a hydrogen heat exchanger, a pure water tank, an evaporator, and a first circulation pump.

[0009] The fuel preheater has a first flow path and a second flow path that can exchange heat with each other, and a first heater, the first heater being used to heat the first flow path and the second flow path;

[0010] The hydrogen storage tank, the hydrogen pressure reducing valve, the first flow meter, the first mixer, the first flow path, and the gas inlet on the fuel side of the reversible solid oxide battery unit are connected in sequence through pipelines.

[0011] The hydrogen heat exchanger has a third flow path and a fourth flow path that can exchange heat with each other;

[0012] The gas outlet on the fuel side of the reversible solid oxide battery unit, the second flow path, the third flow path, the hydrogen condenser, the hydrogen compressor, and the hydrogen storage tank are connected in sequence through pipelines;

[0013] The pure water tank is connected in sequence to the first circulating pump, the fourth flow path, the evaporator, and the first mixer via pipelines.

[0014] The air handling unit includes an oxygen-enriched storage tank, an oxygen booster pump, a distributor, an oxygen condenser, an oxygen heat exchanger, an air preheater, an oxygen pressure reducing valve, a second flow meter, a second mixer, and a blower.

[0015] The air preheater has a fifth flow path and a sixth flow path that can exchange heat with each other, and a second heater, the second heater being used to heat the fifth flow path and the sixth flow path;

[0016] The oxygen-enriched storage tank, the oxygen pressure reducing valve, the second flow meter, the second mixer, the fifth flow path, and the air inlet on the air side of the reversible solid oxide battery unit are connected in sequence through pipelines;

[0017] The blower is connected to the second mixer via a pipeline;

[0018] The oxygen heat exchanger has a seventh flow path and an eighth flow path that can exchange heat with each other.

[0019] The air outlet on the air side of the reversible solid oxide battery cell, the fifth flow path, the seventh flow path, the oxygen condenser, the flow divider, the oxygen booster pump, and the oxygen-enriched storage tank are connected in sequence.

[0020] The fourth flow path, the eighth flow path, and the evaporator are connected in sequence;

[0021] The splitter also has an vent.

[0022] In an optional embodiment, the fuel processing unit further includes an exhaust gas recirculation unit;

[0023] The exhaust gas recirculation unit is connected between the outlet of the third flow path and the inlet of the first flow path via a pipe, so as to send the gas with insufficient electrochemical reaction at the fuel side outlet of the reversible solid oxide battery unit back into the fuel side inlet of the reversible solid oxide battery unit.

[0024] In an optional embodiment, the exhaust gas recirculation unit includes a reflux hydrogen condenser and a second circulation pump; one end of the reflux hydrogen condenser is connected to the outlet of the third flow path via a pipe, the second circulation pump is connected to the other end of the reflux hydrogen condenser, and the second circulation pump is connected to the inlet of the first flow path; or,

[0025] The exhaust gas recirculation unit includes a second hydrogen pressure reducing valve, a flow meter, and an ejector. The hydrogen storage tank, the second hydrogen pressure reducing valve, the flow meter, and the ejector are connected in sequence. The ejector is also connected between the outlet of the third flow path and the inlet of the first flow path. The hydrogen flowing out of the hydrogen storage tank can cause the ejector to operate so as to introduce the gas flowing out of the third flow path into the inlet of the first flow path.

[0026] Secondly, this embodiment provides a control method for a reversible solid oxide battery system, which is applied to the reversible solid oxide battery system described in any of the above embodiments;

[0027] The method includes:

[0028] Obtain the required load P of the external load;

[0029] Determine whether the demand load P is greater than 0;

[0030] If the demand load P > 0, the reversible solid oxide battery system is controlled to operate in power generation mode, and the rated power generation P of the reversible solid oxide battery unit is determined. fc Based on the demand load P and the rated power generation P fc Determine the water / hydrogen ratio and oxygen / nitrogen ratio of the gases supplied to the reversible solid oxide battery unit by the fuel processing unit and the air processing unit;

[0031] If the required load P ≤ 0, the reversible solid oxide battery system is controlled to operate in electrolysis mode, and the rated electrolysis power P of the reversible solid oxide battery cell is determined. el Based on the required load P and the rated electrolysis power P el The water / hydrogen ratio and oxygen / nitrogen ratio of the gases supplied to the reversible solid oxide battery unit by the fuel processing unit and the air processing unit are determined.

[0032] In an optional implementation, the step is based on the demand load P and the rated power generation P. fc The steps for determining the water-to-hydrogen ratio and the oxygen-to-nitrogen ratio of the gases supplied to the reversible solid oxide battery unit by the fuel processing unit and the air processing unit include:

[0033] The air handling unit is controlled to supply an oxygen-nitrogen mixture with an oxygen / nitrogen ratio of 0.5 to the air side of the reversible solid oxide battery cell;

[0034] Determine the absolute value of the demand load P and the rated power generation P. fc Relationship;

[0035] If |P|≥0.5*P fcThe amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0; wherein, a water / hydrogen ratio of 0 indicates that the supply of water vapor is stopped.

[0036] If 0.4 * P fc ≤|P|<0.5*P fc When the amount of hydrogen is calculated, the amount of water vapor is adjusted so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.1.

[0037] If 0.3* fc ≤|P|<0.4*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.2.

[0038] If 0.2*P fc ≤|P|<0.3*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.3.

[0039] If 0.1*P fc ≤|P|<0.2*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.4.

[0040] If |P| < 0.1*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.5.

[0041] In an optional implementation, the steps of calculating the amount of hydrogen and the total flow rate of oxygen / nitrogen gas include:

[0042] The efficiency of the reversible solid oxide battery system in power generation mode is used as the optimization target;

[0043] The fuel utilization rate, oxygen / nitrogen ratio, and output current of the reversible solid oxide battery cell in power generation mode are selected as decision variables in the optimization process.

[0044] Inequality constraints are constructed by selecting the operating temperature and temperature gradient of the stack in the reversible solid oxide battery cell.

[0045] Select the demand load, and construct equation constraints using the input oxygen / nitrogen ratio and the input water / hydrogen ratio;

[0046] The optimal decision variable values ​​are obtained using the least squares method so that the reversible solid oxide battery system achieves the highest efficiency.

[0047] Based on the fuel utilization rate and the oxygen-nitrogen ratio after the reaction, the corresponding hydrogen reference flow rate and total oxygen / nitrogen gas flow rate are calculated.

[0048] In an optional implementation, the method is based on the demand load P and the rated electrolysis power P. el The steps of determining the water / hydrogen ratio and oxygen / nitrogen ratio of the gases supplied to the reversible solid oxide battery unit by the fuel processing unit and the air processing unit include:

[0049] The air handling unit is controlled to stop supplying oxygen-enriched gas to the reversible solid oxide battery unit and supply air to make the oxygen / nitrogen ratio 0.21.

[0050] Determine the absolute value of the demand load P and the rated electrolysis power P. el Relationship;

[0051] If |P|≥0.5*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.95.

[0052] If 0.4 * P el ≤|P|<0.5*P el When the amount of water vapor is calculated, the amount of hydrogen is adjusted so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.9.

[0053] If 0.3*P el ≤|P|<0.4*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.8.

[0054] If 0.2*P el ≤|P|<0.3*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.7.

[0055] If 0.1*P el ≤|P|<0.2*Pel The amount of hydrogen is then adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.6.

[0056] If |P| < 0.1*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor, so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.5.

[0057] In an optional implementation, the steps of calculating the amount of water vapor and the total oxygen / nitrogen gas flow rate include:

[0058] The efficiency of the reversible solid oxide battery system in electrolysis mode is used as the optimization target;

[0059] The water vapor utilization rate, oxygen / nitrogen ratio, and input current of the reversible solid oxide battery cell in electrolysis mode were selected as decision variables in the optimization process.

[0060] Inequality constraints are constructed by selecting the stack operating temperature and temperature gradient in the reversible solid oxide battery cell.

[0061] Select the demand load, and construct equation constraints using the input oxygen / nitrogen ratio and the input water / hydrogen ratio;

[0062] The optimal decision variable values ​​are obtained using the least squares method so that the reversible solid oxide battery system achieves the highest efficiency.

[0063] Based on the steam utilization rate and the oxygen-nitrogen ratio after the reaction, calculate the steam reference flow rate and the total oxygen / nitrogen gas flow rate.

[0064] In an optional implementation, the method further includes:

[0065] In electrolysis mode, the exhaust gas from the fuel side of the reversible solid oxide battery cell is stored after heat exchange.

[0066] The exhaust gas from the air side of the reversible solid oxide battery cell is stored after heat exchange.

[0067] In an optional implementation, the control method further includes:

[0068] When multiple actuators control the corresponding flow loop simultaneously, the first and second flow meters are controlled first to respond to load changes, and then the first circulating pump and the blower are controlled to adjust the flow in the opposite direction.

[0069] The hydrogen flow rate can be controlled by one or both of the first flow meter and the second circulation pump simultaneously; the oxygen flow rate can be controlled by one or both of the second flow meter and the blower simultaneously.

[0070] The beneficial effects of the reversible solid oxide battery system and its control method provided in the embodiments of the present invention include, for example:

[0071] This application simplifies the structure of the reversible solid oxide battery system by configuring a fuel processing unit, an air processing unit, a reversible solid oxide battery cell, and a control unit. Furthermore, the structure is optimized based on the load requirements of the external load and the rated electrolysis power P of the reversible solid oxide battery cell. el and the rated power generation P of the reversible solid oxide battery cell fc Adjusting the water-hydrogen ratio and oxygen-nitrogen ratio entering the reversible solid oxide battery cell allows for flexible adaptation to different load variations and improves conversion efficiency. Attached Figure Description

[0072] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0073] Figure 1 This is a schematic diagram of a reversible solid oxide battery system provided in an embodiment of the present invention;

[0074] Figure 2 A schematic diagram of an ejector used in a reversible solid oxide battery system provided in an embodiment of the present invention;

[0075] Figure 3 This is a schematic diagram of a reversible solid oxide battery system in power generation mode according to an embodiment of the present invention;

[0076] Figure 4 A schematic diagram of the flow path for water vapor supply in the power generation mode of the reversible solid oxide battery system provided in an embodiment of the present invention;

[0077] Figure 5 A schematic diagram of the flow path of the reversible solid oxide battery system in electrolysis mode provided in an embodiment of the present invention;

[0078] Figure 6 This is a schematic diagram showing the connection relationship between the control unit and various electronic components in a reversible solid oxide battery system provided in an embodiment of the present invention.

[0079] Icons: 100 - Reversible solid oxide battery system; 110 - Fuel processing unit; 111 - Hydrogen storage tank; 112 - Hydrogen pressure reducing valve; 113 - First mixer; 114 - Fuel preheater; 115 - Hydrogen compressor; 116 - Hydrogen condenser; 117 - Hydrogen heat exchanger; 118 - Pure water tank; 119 - First circulation pump; 121 - Evaporator; 130 - Air processing unit; 131 - Oxygen-enriched storage tank; 132 - Oxygen booster pump; 133 - Diverter; 134 - Oxygen condenser; 135 - Oxygen heat exchanger; 136 - Air preheater; 137 - Oxygen pressure reducing valve; 138 - Second mixer; 139 - Blower; 150 - Reversible solid oxide battery unit; 170 - Exhaust gas recirculation unit; 171 - Return hydrogen condenser; 172 - Second circulation pump; 173 - Second hydrogen pressure reducing valve; 174 - Ejector. Detailed Implementation

[0080] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0081] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0082] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0083] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0084] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0085] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0086] Example

[0087] Please provide parameters Figure 1 This embodiment provides a reversible solid oxide battery system 100, which can be more conveniently and flexibly controlled with simplified structure.

[0088] Please provide parameters Figure 1 In this embodiment, the reversible solid oxide battery system 100 includes a fuel processing unit 110, an air processing unit 130, a reversible solid oxide battery unit 150, and a control unit. The reversible solid oxide battery unit 150 is connected to an external load to convert electrical energy and water into hydrogen and oxygen when the external load has surplus power, and when the external load has insufficient power to electrochemically convert hydrogen and oxygen into electrical energy. The fuel processing unit 110 is connected to the fuel side of the reversible solid oxide battery unit 150 via a pipeline to provide water vapor and recovered hydrogen to the fuel side of the reversible solid oxide battery unit 150 when the reversible solid oxide battery unit 150 is in electrolysis mode, and to provide hydrogen to the fuel side of the reversible solid oxide battery unit 150 when the reversible solid oxide battery unit 150 is in power generation mode. The air handling unit 130 is connected to the air side of the reversible solid oxide battery unit 150 via a pipe to provide air and collect oxygen-enriched gas to the fuel side of the reversible solid oxide battery unit 150 when the reversible solid oxide battery unit 150 is in electrolysis mode, and to provide oxygen-enriched gas to the fuel side of the reversible solid oxide battery unit 150 when the reversible solid oxide battery unit 150 is in power generation mode.

[0089] This allows for modularity, thus simplifying the structure.

[0090] Please provide parameters Figure 1 and Figure 2In this embodiment, the fuel processing unit 110 includes a hydrogen storage tank 111, a hydrogen pressure reducing valve 112, a first flow meter, a first mixer 113, a fuel preheater 114, a hydrogen compressor 115, a hydrogen condenser 116, a hydrogen heat exchanger 117, a pure water tank 118, a first circulation pump 119, and an evaporator 121. The fuel preheater 114 has a first flow path and a second flow path that can exchange heat with each other, as well as a first heater, which heats the first and second flow paths. The hydrogen storage tank 111, the hydrogen pressure reducing valve 112, the first flow meter, the first mixer 113, the first flow path, and the inlet on the fuel side of the reversible solid oxide battery unit 150 are sequentially connected by pipes. The hydrogen heat exchanger 117 has a third flow path and a fourth flow path that can exchange heat with each other. The outlet on the fuel side of the reversible solid oxide battery unit 150, the second flow path, the third flow path, the hydrogen condenser 116, the hydrogen compressor 115, and the hydrogen storage tank are sequentially connected by pipes. The pure water tank 118, the first circulation pump 119, the fourth flow path, the evaporator 121, and the first mixer 113 are connected in sequence through pipelines.

[0091] The aforementioned piping configuration enables secondary utilization of heat, thereby improving the conversion rate. Furthermore, the inclusion of the first mixer 113 allows for the heating of hydrogen and steam in the fuel preheater 114, saving costs.

[0092] It should be noted that the evaporator 121 integrates an electric heater, which can assist in heating the water to form steam. The first heater also plays an auxiliary heating role in the system, heating the water.

[0093] In this embodiment, the air handling unit 130 includes an oxygen-enriched storage tank 131, an oxygen booster pump 132, a distributor 133, an oxygen condenser 134, an oxygen heat exchanger 135, an air preheater 136, an oxygen pressure reducing valve 137, a second flow meter, a second mixer 138, and a blower 139. The air preheater 136 has a fifth and a sixth flow path that exchange heat with each other, as well as a second heater that heats the fifth and sixth flow paths. The oxygen-enriched storage tank 131, the oxygen pressure reducing valve 137, the second flow meter, the fifth flow path, and the air inlet on the air side of the reversible solid oxide battery unit 150 are sequentially connected via pipes. The blower 139 is connected to the second mixer 138 via a pipe. The oxygen heat exchanger 135 has a seventh and an eighth flow path that exchange heat with each other. The reversible solid oxide battery cell 150 is connected in sequence to the air outlet, the fifth flow path, the seventh flow path, the oxygen condenser 134, the distributor 133, the oxygen booster pump 132, and the oxygen-enriched storage tank 131 on the air side. The fourth flow path, the eighth flow path, and the evaporator 121 are connected in sequence. The distributor 133 also has an air vent.

[0094] The aforementioned piping configuration allows for the secondary utilization of heat to heat water, thereby improving the conversion rate. Furthermore, the inclusion of a second mixer 138 enables the air preheater 136 to heat both the air and oxygen-enriched gas, saving costs.

[0095] It should be noted that the second heater plays an auxiliary heating role in the system.

[0096] Please refer to Figure 1 and Figure 2 In this embodiment, the fuel processing unit 110 further includes an exhaust gas recirculation unit 170; the exhaust gas recirculation unit 170 is connected between the outlet of the third flow path and the inlet of the first flow path through a pipe, so as to send the gas with insufficient electrochemical reaction at the fuel side outlet of the reversible solid oxide battery unit 150 back into the fuel side inlet of the reversible solid oxide battery unit 150.

[0097] Please provide parameters Figure 1 Furthermore, the exhaust gas recirculation unit 170 includes a reflux hydrogen condenser 171 and a second circulation pump 172. One end of the reflux hydrogen condenser 171 is connected to the outlet of the third flow path via a pipe, and the second circulation pump 172 is connected to the other end of the reflux hydrogen condenser 171, and the second circulation pump 172 is connected to the inlet of the first flow path. This allows for the secondary utilization of exhaust gas that has not undergone sufficient electrochemical reaction, thereby improving the conversion rate.

[0098] Please provide parameters Figure 2 In some other embodiments of this application, the exhaust gas recirculation unit 170 includes a second hydrogen pressure reducing valve 173, a third flow meter, and an ejector 174. The hydrogen storage tank 111, the second hydrogen pressure reducing valve 173, the third flow meter, and the ejector 174 are connected in sequence. The ejector 174 is also connected between the outlet of the third flow path and the inlet of the first flow path. The hydrogen flowing out of the hydrogen storage tank 111 can cause the ejector 174 to operate so as to introduce the gas flowing out of the third flow path into the inlet of the first flow path.

[0099] Since the ejector 174 is powered by hydrogen from the hydrogen storage tank 111, it does not require additional electrical energy input, thus saving energy, improving conversion efficiency, and reducing equipment maintenance costs.

[0100] Please refer to Figure 3 and Figure 4 When operating in power generation mode, it consumes stored hydrogen and oxygen-enriched gas to generate electricity to supply external loads. The specific process is as follows:

[0101] Hydrogen gas in hydrogen storage tank 111 enters the fuel-side inlet of reversible solid oxide battery unit 150 via hydrogen pressure reducing valve 112, flow meter, first mixer 113, and first flow path. Gas with incomplete electrochemical reaction at the fuel-side outlet of reversible solid oxide battery unit 150 is fed back into the fuel-side inlet of reversible solid oxide battery unit 150 via the second and fourth flow paths under the action of exhaust gas recirculation unit 170, and then again via the first flow path. This achieves heat recovery from waste gas, insulation of hydrogen heat exchanger 117, and secondary electrochemical reaction of incompletely combusted gas, thereby improving the conversion rate.

[0102] The oxygen-enriched gas in the oxygen-enriched storage tank 131 passes sequentially through the oxygen pressure reducing valve 137, the flow meter, the second mixer 138, and the blower 139, which then sends outside air into the second mixer 138. The mixed oxygen-enriched gas and air are then sent through a fifth flow path to the air inlet on the air side of the reversible solid oxide battery unit 150, where they mix with hydrogen and are then heated by combustion. This process maintains the temperature of the oxygen heat exchanger 135 and allows for the supply of oxygen and nitrogen from the outside.

[0103] Please refer to Figure 5 When operating in electrolysis mode, it consumes electrical energy from an external load to electrolyze water and produce hydrogen and oxygen. The specific working process is as follows:

[0104] Water from the pure water tank 118 of the fuel processing unit 110 flows sequentially through the first circulation pump 119, the fourth flow path, and the sixth flow path. After entering the evaporator 121, it forms water vapor, which mixes with hydrogen from the hydrogen storage tank in the first mixer 113. Then, it flows through the first flow path into the inlet of the reversible solid oxide battery unit 150 on the fuel side for electrolysis. The hydrogen generated by electrolysis at the outlet of the reversible solid oxide battery unit 150 on the fuel side can be stored in the hydrogen storage tank 111 through the second flow path, the third flow path, the hydrogen condenser 116, and the hydrogen compressor 115. Alternatively, hydrogen from the fuel side outlet of the battery unit can be sent back to the inlet of the reversible solid oxide battery unit 150 through the second flow path and the fourth flow path under the action of the tail gas recirculation unit 170.

[0105] The operation of the blower 139 in the air handling unit 130 allows outside air to flow through the second mixer 138 and the fifth flow path into the air-side inlet of the reversible solid oxide battery unit 150, thus participating in water electrolysis. Air discharged from the air-side outlet of the reversible solid oxide battery unit 150, or oxygen-enriched air via the fifth and seventh flow paths, oxygen condenser 134, distributor 133, and oxygen booster pump 132, is stored in the oxygen-enriched storage tank 131 or discharged through the distributor 133. This allows for secondary heat utilization using the air preheater and oxygen heat exchanger 135, thereby improving the conversion rate.

[0106] It should be noted that in this embodiment, control valves are installed on the pipelines connecting the various devices, and the control unit is connected to the control valves to adjust parameters such as flow rate and ratio. Of course, some sensors are also installed to detect the corresponding parameters.

[0107] Please refer to Figures 1 to 6 Secondly, regarding the reversible solid oxide battery system 100 provided in the above embodiments, this embodiment also provides a control method for the reversible solid oxide battery system 100, which is executed by a controller unit. Generally, the controller unit includes a memory and a processor. The memory stores the software program corresponding to the control method described below, and the controller controls the operation according to the software program.

[0108] The methods include:

[0109] S1. Obtain the required load P from the external load;

[0110] It should be noted that the demand load of the external load is given externally. For example, if the external load is the power grid, the power grid will provide a demand load based on demand. It only needs to be monitored and extracted.

[0111] S2. Determine if the demand load P is greater than 0;

[0112] S3. If the demand load P > 0, then control the reversible solid oxide battery system 100 to operate in power generation mode, and determine the rated power generation P of the reversible solid oxide battery unit 150. fc Based on the demand load P and the rated generating capacity P fc Determine the water / hydrogen ratio and oxygen / nitrogen ratio of the gases supplied to the reversible solid oxide battery unit 150 by the fuel processing unit 110 and the air processing unit 130;

[0113] S4. If the demand load P≤0, then control the reversible solid oxide battery system 100 to operate in electrolysis mode, and determine the rated electrolysis power P of the reversible solid oxide battery cell 150. el Based on the demand load P and the rated electrolysis power P el The water / hydrogen ratio and oxygen / nitrogen ratio of the gases supplied to the reversible solid oxide battery unit 150 by the fuel processing unit 110 and the air processing unit 130 are determined.

[0114] The above control method can precisely control the amount of each gas introduced into the reversible solid oxide battery cell 150, thereby increasing the efficiency.

[0115] In power generation mode, step S3 includes the following steps:

[0116] S31, the air handling unit 130 controls the supply of an oxygen-nitrogen mixture with an oxygen / nitrogen ratio of 0.5 to the air side of the reversible solid oxide battery unit 150;

[0117] S32. Determine the absolute value of the demand load P and the rated generating power P. fc Relationship;

[0118] S33. If |P| ≥ 0.5 * P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0; wherein, a water / hydrogen ratio of 0 indicates that the supply of water vapor is stopped.

[0119] S34, If 0.4 * P fc ≤|P|<0.5*P fc When the amount of hydrogen is calculated, the amount of water vapor is adjusted so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.1.

[0120] S35, if 0.3* fc ≤|P|<0.4*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.2.

[0121] S36, If 0.2 * P fc ≤|P|<0.3*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.3.

[0122] S37, If 0.1 * P fc ≤|P|<0.2*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the fuel processing unit 110 supplies a mixed gas with a water / hydrogen ratio of 0.4 to the fuel side of the reversible solid oxide battery unit 150.

[0123] S38. If |P| < 0.1*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.5.

[0124] The above settings ensure that the required fuel ratio for the reaction is supplied in advance, guaranteeing adaptability to changes in flexible load and rapid mode switching.

[0125] In this embodiment, the steps of calculating the amount of hydrogen and the total flow rate of oxygen / nitrogen gas include:

[0126] A1. The efficiency of the reversible solid oxide battery system 100 in power generation mode is used as the optimization target;

[0127] A2. The fuel utilization rate, oxygen / nitrogen ratio, and output current of the reversible solid oxide battery cell 150 in power generation mode are selected as decision variables in the optimization process.

[0128] A3. Select the operating temperature and temperature gradient of the stack in reversible solid oxide battery cell 150 to construct inequality constraints;

[0129] A4. Select the demand load, and construct equation constraints using the input oxygen / nitrogen ratio and the input water / hydrogen ratio;

[0130] A5. Use the least squares method to obtain the optimal decision variable values ​​so that the reversible solid oxide battery system can achieve the highest efficiency.

[0131] A6. Based on the fuel utilization rate and the oxygen-nitrogen ratio after the reaction, the corresponding hydrogen reference flow rate and total oxygen / nitrogen gas flow rate are calculated.

[0132] This allows the hydrogen and water vapor supplied to the combustion side to correspond to the load demand during power generation, thus enabling precise control and flexible adaptation to changes.

[0133] In electrolysis mode, step S4 includes the following sub-steps:

[0134] S41. Control the air handling unit 130 to stop supplying oxygen-enriched gas to the reversible solid oxide battery unit 150 and supply air so that the oxygen / nitrogen ratio is 0.21;

[0135] It should be noted that the oxygen / nitrogen ratio remains unchanged at 0.21 in electrolysis mode.

[0136] S42. Determine the absolute value of the demand load P and the rated electrolysis power P el Relationship;

[0137] S43. If |P| ≥ 0.5 * P el The amount of hydrogen is adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.95.

[0138] S44, If 0.4 * P el ≤|P|<0.5*P elWhen the amount of water vapor is calculated, the amount of hydrogen is adjusted so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.9.

[0139] S45, If 0.3 * P el ≤|P|<0.4*P el The amount of hydrogen is adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.8.

[0140] S46. If 0.2 * P el ≤|P|<0.3*P el The amount of hydrogen is adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.7.

[0141] S47, If 0.1 * P el ≤|P|<0.2*P el The amount of hydrogen is adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.6.

[0142] S48. If |P| < 0.1 * P el The amount of hydrogen is adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit 110 to the fuel side of the reversible solid oxide battery unit 150 is 0.5.

[0143] The above settings enable the supply of fuel in the required proportion for the reaction to be achieved in advance, ensuring adaptability to changes in flexible load and rapid mode switching.

[0144] In this embodiment, the steps of calculating the amount of water vapor and the total flow rate of oxygen / nitrogen gas include:

[0145] B1. The efficiency of the reversible solid oxide battery system 100 in electrolysis mode is used as the optimization target;

[0146] B2. Select the water vapor utilization rate, oxygen / nitrogen ratio and input current of the reversible solid oxide battery cell 150 in electrolysis mode as decision variables in the optimization process.

[0147] B3. Select the stack operating temperature and temperature gradient in reversible solid oxide battery cell 150 to construct inequality constraints;

[0148] B4. Select the demand load, and construct equation constraints based on the input oxygen / nitrogen ratio and the input water / hydrogen ratio;

[0149] B5. Use the least squares method to obtain the optimal decision variable values ​​so that the reversible solid oxide battery system can achieve the highest efficiency.

[0150] B6. Based on the steam utilization rate and the oxygen-nitrogen ratio after the reaction, calculate the steam reference flow rate and the total oxygen / nitrogen gas flow rate.

[0151] The above method allows for the calculation of an accurate water vapor reference flow rate, which in turn allows for the calculation of the hydrogen quantity using a ratio, thus enabling flexible adaptation to load changes.

[0152] In this embodiment, the method further includes the following step S6:

[0153] S6. In electrolysis mode, the exhaust gas on the fuel side of the reversible solid oxide battery unit 150 is controlled to be stored after heat exchange and condensation; the exhaust gas on the air side of the reversible solid oxide battery unit 150 is controlled to be stored after heat exchange.

[0154] This allows the hydrogen and oxygen generated during electrolysis to be collected and used in the power generation process.

[0155] It should also be noted that during the power generation process, the exhaust gas generated on the air side of the reversible solid oxide battery cell 150 is discharged through the splitter 133.

[0156] In this embodiment, the control method further includes:

[0157] S7. When multiple actuators control the corresponding flow loop simultaneously, the first flow meter and the second flow meter are controlled first to respond to load changes, and then the first circulating pump 119 and the blower 139 are controlled to adjust the flow in the opposite direction.

[0158] The hydrogen flow rate can be controlled by one or both of the first flow meter and the second circulation pump 172 simultaneously; the oxygen flow rate can be controlled by one or both of the second flow meter and the blower 139 simultaneously.

[0159] The above controls can make flow control response faster and more stable.

[0160] It should be noted that the specific control unit can use a feedforward controller, combined with the fuel utilization rate (in power generation mode) / steam utilization rate (in electrolysis mode) and the output oxygen-nitrogen ratio given by the optimizer, to calculate the corresponding hydrogen reference flow rate (in power generation mode), steam reference flow rate (in electrolysis mode), high-ratio oxygen / nitrogen total flow rate (in power generation mode), and total air flow rate (in electrolysis mode). Through distributed PID and MPC controllers, the tracking control of their respective reference flow rates, follow-up flow rates, and total flow rates is achieved. Where the flow control actuator is a flow meter type, a PID controller is used; the flow control actuator is a rotating device such as the second circulation pump 172 or the blower 139.

[0161] Of course, in this embodiment, an electrically controlled valve can also be installed in each flow path to control the flow rate.

[0162] In summary, the embodiments of the present invention provide a reversible solid oxide battery system 100 and its control method, and the working principle and beneficial effects of the latter include:

[0163] This embodiment simplifies the structure by configuring the reversible solid oxide battery system 100 as a fuel processing unit 110, an air processing unit 130, a reversible solid oxide battery unit 150, and a control unit. Furthermore, by adjusting the water-hydrogen ratio and oxygen-nitrogen ratio entering the reversible solid oxide battery unit 150 according to the external load requirements, the rated electrolysis power Pel of the reversible solid oxide battery unit 150, and the rated power generation power Pfc of the reversible solid oxide battery unit 150, precise dynamic control of the system can be achieved, and it can adapt to different load changes.

[0164] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A reversible solid oxide battery system, characterized in that, This includes a fuel processing unit, an air processing unit, and a reversible solid oxide battery unit; The reversible solid oxide battery cell is used to connect to an external load; The fuel processing unit includes a hydrogen storage tank, a hydrogen pressure reducing valve, a first flow meter, a first mixer, a fuel preheater, a hydrogen compressor, a hydrogen condenser, a hydrogen heat exchanger, a pure water tank, an evaporator, and a first circulation pump. The fuel preheater has a first flow path and a second flow path that can exchange heat with each other, and a first heater, the first heater being used to heat the first flow path and the second flow path; The hydrogen storage tank, the hydrogen pressure reducing valve, the first flow meter, the first mixer, the first flow path, and the gas inlet on the fuel side of the reversible solid oxide battery unit are connected in sequence through pipelines. The hydrogen heat exchanger has a third flow path and a fourth flow path that can exchange heat with each other; The gas outlet on the fuel side of the reversible solid oxide battery unit, the second flow path, the third flow path, the hydrogen condenser, the hydrogen compressor, and the hydrogen storage tank are connected in sequence through pipelines; The pure water tank is connected in sequence to the first circulating pump, the fourth flow path, the evaporator, and the first mixer via pipelines. The air handling unit includes an oxygen-enriched storage tank, an oxygen booster pump, a distributor, an oxygen condenser, an oxygen heat exchanger, an air preheater, an oxygen pressure reducing valve, a second flow meter, a second mixer, and a blower. The air preheater has a fifth flow path and a sixth flow path that can exchange heat with each other, and a second heater, the second heater being used to heat the fifth flow path and the sixth flow path; The oxygen-enriched storage tank, the oxygen pressure reducing valve, the second flow meter, the second mixer, the fifth flow path, and the air inlet on the air side of the reversible solid oxide battery unit are connected in sequence through pipelines; The blower is connected to the second mixer via a pipeline; The oxygen heat exchanger has a seventh flow path and an eighth flow path that can exchange heat with each other. The air outlet on the air side of the reversible solid oxide battery cell, the fifth flow path, the seventh flow path, the oxygen condenser, the flow divider, the oxygen booster pump, and the oxygen-enriched storage tank are connected in sequence. The fourth flow path, the eighth flow path, and the evaporator are connected in sequence; The splitter also has an vent.

2. The reversible solid oxide battery system according to claim 1, characterized in that, The fuel processing unit also includes an exhaust gas recirculation unit; The exhaust gas recirculation unit is connected between the outlet of the third flow path and the inlet of the first flow path via a pipe, so as to send the gas with insufficient electrochemical reaction at the fuel side outlet of the reversible solid oxide battery unit back into the fuel side inlet of the reversible solid oxide battery unit.

3. The reversible solid oxide battery system according to claim 2, characterized in that, The exhaust gas recirculation unit includes a reflux hydrogen condenser and a second circulation pump; one end of the reflux hydrogen condenser is connected to the outlet of the third flow path via a pipe, and the second circulation pump is connected to the other end of the reflux hydrogen condenser, and the second circulation pump is connected to the inlet of the first flow path; or, The exhaust gas recirculation unit includes a second hydrogen pressure reducing valve, a flow meter, and an ejector. The hydrogen storage tank, the second hydrogen pressure reducing valve, the flow meter, and the ejector are connected in sequence. The ejector is also connected between the outlet of the third flow path and the inlet of the first flow path. The hydrogen flowing out of the hydrogen storage tank can cause the ejector to operate so as to introduce the gas flowing out of the third flow path into the inlet of the first flow path.

4. A control method for a reversible solid oxide battery system, characterized in that, Applied to the reversible solid oxide battery system according to any one of claims 1-3; The method includes: Obtain the required load P of the external load; Determine whether the demand load P is greater than 0; If the demand load P > 0, the reversible solid oxide battery system is controlled to operate in power generation mode, and the rated power generation P of the reversible solid oxide battery cell is determined. fc Based on the demand load P and the rated power generation P fc Determine the water / hydrogen ratio and oxygen / nitrogen ratio of the gases supplied to the reversible solid oxide battery unit by the fuel processing unit and the air processing unit; If the required load P ≤ 0, the reversible solid oxide battery system is controlled to operate in electrolysis mode, and the rated electrolysis power P of the reversible solid oxide battery cell is determined. el Based on the required load P and the rated electrolysis power P el The water / hydrogen ratio and oxygen / nitrogen ratio of the gases supplied to the reversible solid oxide battery unit by the fuel processing unit and the air processing unit are determined.

5. The control method for a reversible solid oxide battery system according to claim 4, characterized in that, Based on the demand load P and the rated power generation P fc The steps for determining the water-to-hydrogen ratio and the oxygen-to-nitrogen ratio of the gases supplied to the reversible solid oxide battery unit by the fuel processing unit and the air processing unit include: The air handling unit is controlled to supply an oxygen-nitrogen mixture with an oxygen / nitrogen ratio of 0.5 to the air side of the reversible solid oxide battery cell; Determine the absolute value of the demand load P and the rated power generation P. fc Relationship; If |P|≥0.5*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen, so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0; wherein, a water / hydrogen ratio of 0 indicates that the supply of water vapor is stopped. If 0.4 * P fc ≤|P|<0.5*P fc When the amount of hydrogen is calculated, the amount of water vapor is adjusted so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

1. If 0.3* fc ≤|P|<0.4*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

2. If 0.2*P fc ≤|P|<0.3*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

3. If 0.1*P fc ≤|P|<0.2*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

4. If |P| < 0.1*P fc The amount of water vapor is adjusted based on the calculated amount of hydrogen so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

5.

6. The control method for a reversible solid oxide battery system according to claim 5, characterized in that, The steps for calculating the amount of hydrogen and the total flow rate of oxygen / nitrogen gas include: The efficiency of the reversible solid oxide battery system in power generation mode is used as the optimization target; The fuel utilization rate, oxygen / nitrogen ratio, and output current of the reversible solid oxide battery cell in power generation mode are selected as decision variables in the optimization process. Inequality constraints are constructed by selecting the operating temperature and temperature gradient of the stack in the reversible solid oxide battery cell. Select the demand load, and construct equation constraints using the input oxygen / nitrogen ratio and the input water / hydrogen ratio; The optimal decision variable values ​​are obtained using the least squares method so that the reversible solid oxide battery system achieves the highest efficiency. Based on the fuel utilization rate and the oxygen-nitrogen ratio after the reaction, the corresponding hydrogen reference flow rate and total oxygen / nitrogen gas flow rate are calculated.

7. The control method for a reversible solid oxide battery system according to any one of claims 4-6, characterized in that, Based on the demand load P and the rated electrolysis power P el The steps of determining the water / hydrogen ratio and oxygen / nitrogen ratio of the gases supplied to the reversible solid oxide battery unit by the fuel processing unit and the air processing unit include: The air handling unit is controlled to stop supplying oxygen-enriched gas to the reversible solid oxide battery unit and supply air to make the oxygen / nitrogen ratio 0.

21. Determine the absolute value of the demand load P and the rated electrolysis power P. el Relationship; If |P|≥0.5*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor, so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

95. If 0.4 * P el ≤|P|<0.5*P el When the amount of water vapor is calculated, the amount of hydrogen is adjusted so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

9. If 0.3*P el ≤|P|<0.4*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor, so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

8. If 0.2*P el ≤|P|<0.3*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor, so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

7. If 0.1*P el ≤|P|<0.2*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

6. If |P| < 0.1*P el The amount of hydrogen is then adjusted based on the calculated amount of water vapor, so that the water / hydrogen ratio of the mixed gas supplied by the fuel processing unit to the fuel side of the reversible solid oxide battery unit is 0.

5.

8. The control method for a reversible solid oxide battery system according to claim 7, characterized in that, The steps for calculating the amount of water vapor and the total flow rate of oxygen / nitrogen gas include: The efficiency of the reversible solid oxide battery system in electrolysis mode is used as the optimization target; The water vapor utilization rate, oxygen / nitrogen ratio, and input current of the reversible solid oxide battery cell in electrolysis mode were selected as decision variables in the optimization process. Inequality constraints are constructed by selecting the stack operating temperature and temperature gradient in the reversible solid oxide battery cell. Select the demand load, and construct equation constraints using the input oxygen / nitrogen ratio and the input water / hydrogen ratio; The optimal decision variable values ​​are obtained using the least squares method so that the reversible solid oxide battery system achieves the highest efficiency. Based on the steam utilization rate and the oxygen-nitrogen ratio after the reaction, calculate the steam reference flow rate and the total oxygen / nitrogen gas flow rate.

9. The control method for a reversible solid oxide battery system according to claim 7, characterized in that, The method further includes: In electrolysis mode, the exhaust gas from the fuel side of the reversible solid oxide battery cell is stored after heat exchange. The exhaust gas from the air side of the reversible solid oxide battery cell is stored after heat exchange.

10. The control method for a reversible solid oxide battery system according to any one of claims 4-6, characterized in that, The control method further includes: When multiple actuators control the corresponding flow loop simultaneously, the first and second flow meters are controlled first to respond to load changes, and then the first circulating pump and the blower are controlled to adjust the flow in the opposite direction. The hydrogen flow rate can be controlled by one or both of the first flow meter and the second circulation pump simultaneously; the oxygen flow rate can be controlled by one or both of the second flow meter and the blower simultaneously.

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