Water electrolysis hydrogen production system adaptive to high-voltage power supply

Abstract

The utility model belongs to the technical field of water electrolysis hydrogen production, and discloses a water electrolysis hydrogen production system matched with a high-voltage power supply. The water electrolysis hydrogen production system mainly comprises a power grid, a transformer, a rectifying unit, a power supply unit, an electrolytic bath and other structural units. The output end of the transformer is connected with the rectification unit; the positive electrode of the power supply unit is connected with the positive electrode of the electrolytic cell, and the negative electrode of the power supply unit is connected with the negative electrode of the electrolytic cell; the negative electrode output end of the electrolytic cell is used for performing hydrogen gas-liquid separation and purifying each module unit of the hydrogen; the positive electrode output end of the electrolytic bath is connected with each module unit for oxygen side gas-liquid separation and oxygen purification; according to the water electrolysis hydrogen production system provided by the utility model, the rectification unit, the power supply unit and the electrolytic bath are matched, so that electric power can be efficiently transmitted between the power supply and the electrolytic bath, stable and efficient operation of the hydrogen production device can be realized, and meanwhile, the system cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of water electrolysis hydrogen production system, in particular to a water electrolysis hydrogen production system adapted to a high-voltage power supply. Background Art

[0002] The alkaline water electrolysis hydrogen production technology widely used in industrial applications refers to the process of electrolyzing water in an alkaline solution to generate hydrogen. Generally, a strong alkaline solution such as potassium hydroxide is used as an electrolyte. After direct current is passed between the two electrodes of the electrolyzer, water molecules are decomposed into hydrogen and oxygen under electrochemical reactions. For the cost of the water electrolysis hydrogen production system, the cost of the power module is relatively high.

[0003] Traditional alkaline water electrolysis hydrogen production systems mostly use low-voltage, high-current power supplies. This low-voltage, high-current power supply method has complex lines, large line losses, and high costs. The high-voltage, low-current power supply system uses a single-stage conversion structure, which is simple in structure and low in cost. Existing high-voltage power supply technologies mostly use transformers and thyristors, which are prone to generate a large amount of harmonic pollution during operation, and cannot control the power factor of the power supply, resulting in low system efficiency and energy waste. Therefore, it is of great significance to develop a simple, efficient and stable power supply and a low-cost water electrolysis hydrogen production system that is compatible with it.

[0004] To this end, the utility model proposes a water electrolysis hydrogen production system adapted to a high-voltage power supply. Utility Model Content

[0005] The utility model aims to provide a water electrolysis hydrogen production system adapted to a high-voltage power supply, which can reduce costs and realize stable, continuous and efficient water electrolysis hydrogen production.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A water electrolysis hydrogen production system adapted to a high-voltage power supply, comprising a power grid, a transformer, a rectifier unit, a power supply unit and an electrolyzer;

[0008] The power grid is connected to the input end of the transformer, and the output end of the transformer is connected to the input end of the rectifier unit;

[0009] The output end of the rectifier unit is connected to a power supply unit, and the power supply unit includes a positive bus filter capacitor, a negative bus filter capacitor, a Boost conversion circuit and an output filter capacitor;

[0010] The input end of the positive bus filter capacitor and the input end of the negative bus filter capacitor are both connected to the output end of the rectifier unit, the output end of the positive bus filter capacitor and the output end of the negative bus filter capacitor are both connected to the Boost conversion circuit, the Boost conversion circuit is connected to the output filter capacitor, and the output filter capacitor is connected to the electrolytic cell.

[0011] Preferably, the negative electrode output end of the electrolyzer is connected to the input end of the hydrogen side gas-liquid separator, the gas output end of the hydrogen side gas-liquid separator is connected to the input end of the hydrogen side washing and cooling tower, the output end of the hydrogen side washing and cooling tower is connected to the input end of the compression unit, and the compression unit can compress the hydrogen to be purified; the output end of the compression unit is connected to the input end of the hydrogen deoxygenation tower, the output end of the hydrogen deoxygenation tower is connected to a drying unit, the drying unit can remove residual moisture in the hydrogen, and the output end of the drying unit outputs hydrogen;

[0012] The positive electrode output end of the electrolytic cell is connected to the input end of the oxygen side gas-liquid separator, the gas output end of the oxygen side gas-liquid separator is connected to the input end of the oxygen side washing and cooling tower, and the output end of the oxygen side washing and cooling tower is connected to an oxygen storage unit, which is used to store oxygen.

[0013] Preferably, the liquid output end of the hydrogen-side gas-liquid separator and the liquid output end of the oxygen-side gas-liquid separator are both connected to the input end of an alkali liquid circulation pump, and the output end of the alkali liquid circulation pump is connected to the electrolytic cell.

[0014] Preferably, a condensation water unit is also provided, the output end of the condensation water unit is connected to the input end of a water replenishment pump, the output end of the water replenishment pump is connected to a hydrogen side gas-liquid separator, and the hydrogen side gas-liquid separator is connected to the electrolytic cell through a pipeline, and can be used to replenish water consumed in the electrolysis reaction.

[0015] Preferably, the rectifier unit includes an IGBT switch tube capable of converting a three-phase AC voltage into a DC voltage.

[0016] Preferably, at least two groups of electrolytic cells are provided, and the multiple electrolytic cells are connected in series.

[0017] Preferably, the drying unit includes a hydrogen adsorption drying tower and a hydrogen adsorption regeneration tower, which can remove residual moisture in the hydrogen by cyclic operation.

[0018] The beneficial effects of the utility model are as follows:

[0019] The water electrolysis hydrogen production system provided by the utility model adopts a high-voltage power supply, which can significantly reduce the amount of electricity required for electrolysis under the same current conditions, improve the current efficiency and improve the energy utilization efficiency; at the same time, by adding a rectifier unit and a power supply unit, a stable DC high-voltage power supply that meets the electrolysis conditions is generated by the control means of electronic devices, and efficient power supply for the water electrolysis hydrogen production process is achieved; through the cooperation of the rectifier unit, the power supply unit and the electrolyzer, it can be ensured that the power is efficiently transmitted between the power supply and the electrolyzer, and the stable and efficient operation of the hydrogen production device can be achieved, and the system material manufacturing cost is reduced at the same time; by arranging a hydrogen side washing and cooling tower, a compression unit, a hydrogen deoxygenation tower and a drying unit at the output end of the hydrogen side gas-liquid separator to purify the hydrogen, and finally dry and pure hydrogen can be obtained; at the same time, by arranging an alkali liquid circulation pump to send the alkali liquid separated in the hydrogen side gas-liquid separator and the oxygen side gas-liquid separator back to the electrolyzer for continuous recycling to provide an alkaline environment, it can be relatively cost-saving; the water electrolysis hydrogen production system provided by the utility model has a simple structure and is easy to operate, use and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure is a schematic diagram of the connection relationship of each module unit of the utility model, wherein the arrow indicates the flow direction of gas or liquid, "+" represents the positive electrode, and "-" represents the negative electrode;

[0021] Among them, 1-grid, 2-transformer, 3-rectifier unit, 4-power supply unit, 5-electrolyzer;

[0022] H 2 : 61-hydrogen side gas-liquid separator, 62-hydrogen side washing and cooling tower, 63-compression unit, 64-hydrogen deoxygenation tower, 65-drying unit;

[0023] O 2 : 71- oxygen side gas-liquid separator, 72- hydrogen side washing and cooling tower, 73- oxygen storage unit;

[0024] 8-Alkali solution circulation pump. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0026] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Combination Figure 1 As shown, the utility model proposes a water electrolysis hydrogen production system adapted to a high-voltage power supply, which can realize stable, continuous and efficient water electrolysis hydrogen production. The water electrolysis hydrogen production system mainly includes a power grid 1, a transformer 2, a rectifier unit 3, a power supply unit 4 and an electrolyzer 5 and other structural units.

[0028] The grid 1 outputs a high-voltage power supply, which is connected to the input end of the transformer 2, and the output end of the transformer 2 is connected to the rectifier unit 3. The transformer 2 is used to adjust the voltage parameters and provide a stable, isolated, and safe power input. It is a key device for connecting the water electrolysis hydrogen production system with the grid 1.

[0029] The rectifier unit 3 includes an IGBT switch tube, which can convert the three-phase AC voltage into a DC voltage. By controlling the conduction angle and cut-off angle of the IGBT switch tube, the power factor of the rectifier circuit can be adjusted. By detecting the input voltage and current parameters, using power factor calculation and closed-loop control, the trigger control signal of the IGBT switch tube is adjusted in real time to achieve an input end power factor close to 1, which is conducive to the stable and efficient operation of the hydrogen production system.

[0030] The rectifier unit 3 is connected to the power supply unit 4, which mainly includes components such as a positive bus filter capacitor, a negative bus filter capacitor, a Boost conversion circuit, and an output filter capacitor. The input end of the positive bus filter capacitor and the input end of the negative bus filter capacitor are both connected to the rectifier unit to suppress the pulsating voltage on the DC bus and smooth the DC voltage. When the IGBT switch tube is turned on, the positive bus filter capacitor and the negative bus filter capacitor are charged, and the voltage across the filter capacitor increases. When the IGBT switch tube is turned off, the positive bus filter capacitor and the negative bus filter capacitor are discharged to supply power to the load, and the voltage across the capacitor decreases. The voltage fluctuation is balanced by charging and discharging, thereby obtaining a smooth DC bus output voltage.

[0031] The output end of the positive bus filter capacitor and the output end of the negative bus filter capacitor are both connected to the Boost conversion circuit. By controlling the on and off states of the switch tube, energy transfer and amplification are achieved. Specifically, when the switch tube is turned on, the inductor stores energy, the capacitor releases energy, and the output voltage rises; when the switch tube is turned off, the inductor releases energy, the capacitor stores energy, and the output voltage drops. Such operations are performed periodically, thereby converting the input voltage into the output voltage and amplifying the output voltage.

[0032] The boost conversion circuit is connected to the output filter capacitor, which includes a positive output filter capacitor and a negative output filter capacitor, and is used to suppress the pulsating voltage at the output end and make the output voltage smooth. When the switch tube in the boost conversion circuit is turned on, the positive output filter capacitor is charged and the output voltage rises; when the switch tube is turned off, the negative output filter capacitor is discharged and the output voltage drops. Through the charging and discharging process, the output filter capacitor suppresses the pulsation of the output voltage and achieves a smooth DC output.

[0033] Combination Figure 1 As shown, by adopting a high-voltage power supply, the amount of electricity required for electrolysis can be significantly reduced under the same current conditions, thereby improving the current efficiency and the energy utilization efficiency; by adopting a rectifier unit 3 and a power supply unit 4, a stable DC high-voltage power supply that meets the electrolysis conditions is generated through the control means of electronic devices, thereby achieving efficient power supply for the process of hydrogen production by electrolysis of water; at the same time, the output voltage of this high-voltage power supply is strictly matched with the input end of the electrolyzer 5, thereby ensuring that electricity can be efficiently transmitted between the power supply unit 4 and the electrolyzer 5.

[0034] The output filter capacitor is connected to the electrolytic cell 5, the positive output filter capacitor is connected to the positive electrode of the electrolytic cell 5, and the negative output filter capacitor is connected to the negative electrode of the electrolytic cell 5. There are at least two groups of electrolytic cells 5, and in this embodiment, four groups of electrolytic cells 5 are provided, and the four electrolytic cells 5 are connected in series.

[0035] Combination Figure 1As shown, the negative electrode output end of the electrolyzer 5 is connected to the input end of the hydrogen side gas-liquid separator 61, and the hydrogen side gas-liquid separator 61 is used to separate the hydrogen produced by electrolysis from the alkali liquid. The gas output end of the hydrogen side gas-liquid separator 61 is connected to the input end of the hydrogen side washing and cooling tower 62, and the hydrogen side washing and cooling tower 62 can further wash the small amount of alkali liquid remaining in the hydrogen. The output end of the hydrogen side washing and cooling tower 62 is connected to the input end of the compression unit 63, and the compression unit 63 can compress the hydrogen to be purified. The output end of the compression unit 63 is connected to the input end of the hydrogen deoxygenation tower 64, and the hydrogen deoxygenation tower 64 can purify the compressed hydrogen and remove some mixed oxygen in the hydrogen produced by water electrolysis. The output end of the hydrogen deoxygenation tower 64 is connected to the drying unit 65, and the drying unit 65 can remove the residual moisture in the hydrogen. The drying unit 65 mainly includes a hydrogen adsorption drying tower and a hydrogen adsorption regeneration tower, and removes the residual moisture in the hydrogen through the circulating working depth. The output end of the drying unit 65 outputs dry and pure hydrogen.

[0036] Combination Figure 1 As shown, the positive electrode output end of the electrolytic cell 5 is connected to the input end of the oxygen side gas-liquid separator 71, and the oxygen side gas-liquid separator 71 is used to separate the oxygen generated by electrolysis from the alkali liquid. The gas output end of the oxygen side gas-liquid separator 71 is connected to the input end of the oxygen side washing and cooling tower 72, and the oxygen side washing and cooling tower 72 can further wash the small amount of alkali liquid remaining in the oxygen. The output end of the oxygen side washing and cooling tower 72 is connected to the oxygen storage unit 73, which is used to store the oxygen obtained from the oxygen side washing and cooling tower 72 for subsequent comprehensive utilization.

[0037] Combination Figure 1 As shown, the liquid output end of the hydrogen-side gas-liquid separator 61 and the liquid output end of the oxygen-side gas-liquid separator 71 are both connected to the input end of the alkali liquid circulation pump 8, and the output end of the alkali liquid circulation pump 8 is connected to the electrolytic cell 5. The alkali liquid circulation pump 8 can be used to return the alkali liquid separated in the hydrogen-side gas-liquid separator 61 and the oxygen-side gas-liquid separator 71 to the electrolytic cell 5 for continuous recycling, thereby providing an alkaline environment.

[0038] Combination Figure 1 As shown, the water electrolysis hydrogen production system is also provided with a condensed water unit 66, the output end of the condensed water unit 66 is connected to the input end of the water replenishment pump 67, the output end of the water replenishment pump 67 is connected to the hydrogen side gas-liquid separator 61, the hydrogen side gas-liquid separator 61 enters the electrolytic cell 5 through a pipeline, and can replenish the water consumed by the electrolysis reaction.

[0039] The utility model can significantly reduce the amount of electricity required for electrolysis under the same current conditions through the high-voltage power supply provided by the power grid 1, thereby improving the current efficiency and the energy utilization efficiency; at the same time, by adopting the rectifier unit 3 and the power supply unit 4, a stable DC high-voltage power supply that meets the electrolysis conditions is generated through the control means of electronic devices, thereby realizing efficient power supply for the process of hydrogen production by electrolysis of water; by arranging a hydrogen side washing and cooling tower 62, a compression unit 63, a hydrogen deoxygenation tower 64 and a drying unit 65 at the output end of the hydrogen side gas-liquid separator 61 to purify the hydrogen, and finally obtain dry and pure hydrogen; at the same time, by adding an alkali liquid circulation pump 8, the alkali liquid separated in the hydrogen side gas-liquid separator 61 and the oxygen side gas-liquid separator 62 is returned to the electrolytic cell 5 for continuous recycling to provide an alkaline environment, which can relatively save costs; the water electrolysis hydrogen production system provided by the utility model has a simple structure and is easy to operate, use and maintain.

[0040] Of course, the above description is only a preferred embodiment of the utility model, and does not limit the patent scope of the utility model. All equivalent structural changes made by using the contents of the utility model specification and drawings under the utility model concept of the utility model, or direct / indirect application in other related technical fields are included in the patent protection scope of the utility model and should be protected by the utility model.

Claims

1. A water electrolysis hydrogen production system adapted to a high voltage power supply, characterized in that: It includes a power grid, a transformer, a rectifier unit, a power supply unit and an electrolyzer; The power grid is connected to the input end of the transformer, and the output end of the transformer is connected to the input end of the rectifier unit; The output end of the rectifier unit is connected to a power supply unit, and the power supply unit includes a positive bus filter capacitor, a negative bus filter capacitor, a Boost conversion circuit and an output filter capacitor; The input end of the positive bus filter capacitor and the input end of the negative bus filter capacitor are both connected to the output end of the rectifier unit, the output end of the positive bus filter capacitor and the output end of the negative bus filter capacitor are both connected to the Boost conversion circuit, the Boost conversion circuit is connected to the output filter capacitor, and the output filter capacitor is connected to the electrolytic cell.

2. A water electrolysis hydrogen production system adapted to a high voltage power supply according to claim 1, characterized in that: The negative electrode output end of the electrolyzer is connected to the input end of the hydrogen-side gas-liquid separator, the gas output end of the hydrogen-side gas-liquid separator is connected to the input end of the hydrogen-side washing and cooling tower, the output end of the hydrogen-side washing and cooling tower is connected to the input end of the compression unit, and the compression unit can compress the hydrogen to be purified; the output end of the compression unit is connected to the input end of the hydrogen deoxygenation tower, the output end of the hydrogen deoxygenation tower is connected to the drying unit, the drying unit can remove residual moisture in the hydrogen, and the output end of the drying unit outputs hydrogen; The positive electrode output end of the electrolytic cell is connected to the input end of the oxygen side gas-liquid separator, the gas output end of the oxygen side gas-liquid separator is connected to the input end of the oxygen side washing and cooling tower, and the output end of the oxygen side washing and cooling tower is connected to an oxygen storage unit, which is used to store oxygen.

3. A water electrolysis hydrogen production system adapted to a high voltage power supply according to claim 2, characterized in that: The liquid output end of the hydrogen-side gas-liquid separator and the liquid output end of the oxygen-side gas-liquid separator are both connected to the input end of the alkali liquid circulation pump, and the output end of the alkali liquid circulation pump is connected to the electrolytic cell.

4. A water electrolysis hydrogen production system adapted to a high voltage power supply according to claim 2, characterized in that: A condensation water unit is also provided, the output end of the condensation water unit is connected to the input end of a water replenishment pump, the output end of the water replenishment pump is connected to a hydrogen side gas-liquid separator, and the hydrogen side gas-liquid separator is connected to the electrolytic cell through a pipeline, which can be used to replenish the water consumed by the electrolysis reaction.

5. The water electrolysis hydrogen production system adapted to a high-voltage power supply according to claim 1, characterized in that: The rectifier unit includes an IGBT switch tube, which can convert a three-phase AC voltage into a DC voltage.

6. A water electrolysis hydrogen production system adapted to a high voltage power supply according to claim 1, characterized in that: The electrolytic cells are arranged in at least two groups, and the multiple electrolytic cells are connected in series.

7. A water electrolysis hydrogen production system adapted to a high voltage power supply according to claim 2, characterized in that: The drying unit comprises a hydrogen adsorption drying tower and a hydrogen adsorption regeneration tower, which can remove residual moisture in the hydrogen by cyclic operation.

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