阅读说明：本技术 一种燃料电池电堆供气系统 (Fuel cell stack gas supply system ) 是由 高勇 陈斌 张选高 张海波 徐增师 于 2019-08-02 设计创作，主要内容包括：本发明公开了一种提升发电效率的燃料电池电堆供气系统,包括空气供给单元、氧气供给单元和混配气体供给单元；空气供给单元包括空滤、空压机和中冷器；氧气供给单元包括氧气储罐、电动调压阀和流量控制器；混配气体供给单元包括混配罐、气液分离器和循环泵,气液分离器对燃料电池电堆电化学反应产生的尾气进行气液分离,经循环泵增压后送入混配罐,与压缩空气和氧气完成均匀混合。本发明设计科学合理,利用气体混配技术有效提升供给燃料电池电堆气体中氧气浓度,利用气体循环技术使燃料电池电堆尾气形成循环达到未反应氧气循环利用和混配气增湿目的,最终实现燃料电池电堆发电效率的提升,具有结构简单、技术难度低、安全可靠和经济效益良好等优点。(The invention discloses a fuel cell stack gas supply system for improving power generation efficiency, which comprises an air supply unit, an oxygen supply unit and a mixed gas supply unit; the air supply unit comprises an air filter, an air compressor and a intercooler; the oxygen supply unit comprises an oxygen storage tank, an electric pressure regulating valve and a flow controller; the mixed gas supply unit comprises a mixing tank, a gas-liquid separator and a circulating pump, wherein the gas-liquid separator is used for carrying out gas-liquid separation on tail gas generated by the electrochemical reaction of the fuel cell stack, and the tail gas is pressurized by the circulating pump and then sent into the mixing tank to be uniformly mixed with compressed air and oxygen. The invention has scientific and reasonable design, effectively improves the concentration of oxygen in the gas supplied to the fuel cell stack by utilizing the gas mixing technology, forms circulation of the tail gas of the fuel cell stack by utilizing the gas circulation technology to achieve the purposes of recycling unreacted oxygen and humidifying mixed gas, and finally realizes the improvement of the power generation efficiency of the fuel cell stack, and has the advantages of simple structure, low technical difficulty, safety, reliability, good economic benefit and the like.)

1. A fuel cell stack gas supply system, characterized by: comprises an air supply unit (1), an oxygen supply unit (2) and a mixed gas supply unit (3); the air supply unit (1) comprises an air filter (11), an air compressor (12) and a intercooler (13) which are sequentially connected through pipelines; the oxygen supply unit (2) comprises an oxygen storage tank (21), an electric pressure regulating valve (22) and a flow controller (23) which are sequentially connected through pipelines; the mixed gas supply unit (3) comprises a mixed tank (3-1) which is respectively connected with an intercooler (13), a flow controller (23) and a fuel cell stack, compressed air generated by an air compressor (12) is cooled by the intercooler (13) and then enters the mixed tank (3-1), and high-pressure oxygen stored in an oxygen tank (21) enters the mixed tank (3-1) through an electric pressure regulating valve (22) and the flow controller (23); the mixed gas supply unit (3) further comprises a gas-liquid separator (32) and a circulating pump (34) which are sequentially connected through a pipeline, wherein the gas-liquid separator (32) is used for carrying out gas-liquid separation on tail gas generated by the electrochemical reaction of the fuel cell stack, and the tail gas is pressurized by the circulating pump (34) and then sent into the mixing tank (3-1) to be uniformly mixed with compressed air and oxygen.

2. A fuel cell stack gas supply system as claimed in claim 1, wherein: the mixed gas supply unit (3) also comprises a pulse electromagnetic valve (33) connected with the gas-liquid separator (32), and discharges fuel cell stack tail gas through pulses with the period of 50 ms.

3. A fuel cell stack gas supply system according to claim 2, wherein: the mixing tank (3-1) is also provided with an overpressure automatic emptying valve for realizing pressure relief and discharge of gas in the tank and a mechanical automatic drain valve for realizing automatic discharge of accumulated liquid in the tank, and the tank body is made of 304 stainless steel.

4. A fuel cell stack gas supply system according to claim 3, wherein: the mixed gas supply unit (3) further comprises an oxygen concentration sensor (a) for analyzing the oxygen concentration in the mixed gas and feeding back a concentration value signal to the air compressor (12), the flow controller (23) and the circulating pump (34) to realize the adjustment of the oxygen concentration value in the gas in the mixed gas tank (3-1).

5. A fuel cell stack gas supply system according to claim 3, wherein: the mixed gas supply unit (3) further comprises a pressure sensor (b) for analyzing the mixed gas pressure and feeding a pressure value signal back to the air compressor (12) and the electric pressure regulating valve (22) to realize the adjustment of the gas pressure value in the mixed tank (3-1).

6. A fuel cell stack gas supply system according to claim 1 or 2 or 3 or 4 or 5, characterized in that: the cooling type of the air compressor (12) and the intercooler (13) is air cooling.

7. A fuel cell stack gas supply system according to claim 1 or 2 or 3 or 4 or 5, characterized in that: the gas-liquid separator (32) is provided with a filter and a mechanical automatic drain valve.

Technical Field

The invention belongs to the technical field of fuel cells, and particularly relates to an air supply system for improving the power generation efficiency of a fuel cell stack.

Background

A fuel cell is a power generation device that directly converts chemical energy existing in a fuel and an oxidant into electric energy through an electrochemical reaction, and has the advantages of high energy conversion efficiency, high energy density, low vibration noise, zero emission, and the like. In addition, hydrogen is a renewable energy source and can be obtained by preparing hydrogen from green energy sources such as solar energy, wind energy, water potential energy, biological energy and the like. Therefore, the fuel cell is regarded as a clean and efficient ideal power device in the 21 st century, is an important way for solving the two problems of resource shortage and pollution deterioration, and has wide development and application prospects in the fields of automobiles, ships, distributed power generation and the like.

The fuel cell stack is a core component of a fuel cell power generation device, and a high power generation efficiency index is always sought. At present, the main technical approaches taken by experts and scholars at home and abroad are to improve the fuel cell stack body, such as the optimization of the bipolar plate structure, the optimization of the membrane electrode material and the like, but the requirements on professional quality, process equipment parameters and the advancement of the material of designers are higher, and the technical difficulty is higher.

Disclosure of Invention

Based on the gas supply system, the gas supply system for improving the power generation efficiency of the fuel cell stack is designed, the system realizes the improvement of the power generation efficiency of the fuel cell stack by utilizing a gas mixing technology, and has the advantages of simple structure, low technical difficulty, safety, reliability, good economic benefit and the like.

The technical scheme adopted by the invention for solving the technical problems is as follows: a fuel cell stack gas supply system comprises an air supply unit, an oxygen supply unit and a mixed gas supply unit; the air supply unit comprises an air filter, an air compressor and a intercooler which are sequentially connected through pipelines; the oxygen supply unit comprises an oxygen storage tank, an electric pressure regulating valve and a flow controller which are sequentially connected through pipelines; the mixed gas supply unit comprises a mixed tank respectively connected with an intercooler, a flow controller and a fuel cell stack, compressed air generated by an air compressor is cooled by the intercooler and then enters the mixed tank, and high-pressure oxygen stored in an oxygen tank enters the mixed tank through an electric pressure regulating valve and the flow controller; the mixed gas supply unit also comprises a gas-liquid separator and a circulating pump which are sequentially connected through a pipeline, wherein the gas-liquid separator is used for carrying out gas-liquid separation on tail gas generated by the electrochemical reaction of the fuel cell stack, and the tail gas is pressurized by the circulating pump and then sent into the mixed tank to be uniformly mixed with compressed air and oxygen.

The mixed gas supply unit of the fuel cell stack gas supply system further comprises a pulse electromagnetic valve connected with the gas-liquid separator, and tail gas of the fuel cell stack is discharged through pulses with the period of 50 ms.

The fuel cell stack gas supply system is characterized in that the mixing tank is also provided with an overpressure automatic emptying valve for realizing pressure relief and discharge of gas in the tank and a mechanical automatic drain valve for realizing automatic discharge of accumulated liquid in the tank, and the tank body is made of 304 stainless steel.

The mixed gas supply unit of the fuel cell stack gas supply system further comprises an oxygen concentration sensor, and the oxygen concentration sensor is used for analyzing the oxygen concentration in the mixed gas and feeding a concentration value signal back to the air compressor, the flow controller and the circulating pump, so that the adjustment of the oxygen concentration value in the gas in the mixed tank is realized.

The mixed gas supply unit of the fuel cell stack gas supply system further comprises a pressure sensor, and the pressure sensor is used for analyzing the mixed gas pressure and feeding a pressure value signal back to the air compressor and the electric pressure regulating valve, so that the adjustment of the gas pressure value in the mixed tank is realized.

The air compressor and the intercooler of the fuel cell stack air supply system are cooled by air.

The gas-liquid separator of the fuel cell stack gas supply system is provided with a filter and a mechanical automatic drain valve.

The invention has the beneficial effects that:

the invention adopts a gas mixing technical scheme, effectively improves the concentration of oxygen in the gas supplied to the fuel cell stack, and realizes the improvement of the power generation efficiency of the fuel cell stack;

2, the invention adopts the gas circulation technical scheme to circulate the tail gas of the fuel cell stack, thereby achieving the purposes of recycling unreacted oxygen and humidifying mixed gas, and realizing the improvement of the utilization rate of the oxygen and the reduction and distribution of the humidifier.

3, the system has simple structure, low technical difficulty, safety, reliability and good economic benefit.

Drawings

FIG. 1 is a schematic diagram of the system of the present invention.

FIG. 2 is a schematic diagram of the construction of the mixing tank of the present invention;

fig. 3 is a schematic diagram of the mixing tank of the present invention.

The figures are numbered: 1-air supply unit, 11-air filter, 12-air compressor, 13-intercooler; 2-oxygen supply unit, 21-oxygen tank, 22-electric pressure regulating valve, 23-flow controller; 3-mixed gas supply unit, 3-1-mixed tank, 1-1-upper end cover, 1-2-tank body, 1-2-1-air inlet channel, 1-2-2-oxygen inlet channel, 1-2-3-tail gas inlet channel, 1-3-lower end cover, 3-2-filter, 3-pressure sensor, 3-4-oxygen concentration sensor, 3-5-overpressure emptying valve, 3-6-liquid collector, 3-7-liquid level switch, 3-8-electromagnetic valve, 32-gas-liquid separator, 33-pulse electromagnetic valve, 34-circulating pump, a-oxygen concentration sensor and b-pressure sensor.

Detailed Description

The invention aims to provide an air supply system for improving the power generation efficiency of a fuel cell stack, aiming at solving the problems of the existing technology for improving the electrical performance index of the fuel cell stack.

The present invention will be described in detail below with reference to the drawings and examples, which are as follows.

As shown in FIG. 1, the invention discloses an air supply system for improving the power generation efficiency of a fuel cell stack, which comprises an air supply unit 1, an oxygen supply unit 2 and a mixed gas supply unit 3.

The air supply unit 1 comprises an air filter 11, an air compressor 12 and a intercooler 13 which are sequentially connected through pipelines, and the cooling type of the air compressor 12 and the intercooler 13 is air cooling.

The oxygen supply unit 2 includes an oxygen tank 21, an electric pressure regulating valve 22, and a flow controller 23 connected in this order via a pipe.

The mixed gas supply unit 3 comprises a mixed tank 3-1, a gas-liquid separator 32, a pulse electromagnetic valve 33, a circulating pump 34, an oxygen concentration sensor a and a pressure sensor b; the circulating pump 34 is used for providing power for circulating the tail gas of the fuel cell to the blending tank 3-1, so that the oxygen is recycled and the gas in the blending tank 3-1 is humidified; the oxygen concentration sensor a is used for analyzing the oxygen concentration in the mixing gas and feeding a concentration value signal back to the air compressor 12, the flow controller 23 and the circulating pump 34 to realize the adjustment of the oxygen concentration value in the gas in the mixing tank 3-1; the pressure sensor b is used for analyzing the mixed gas pressure and feeding a pressure value signal back to the air compressor 12 and the electric pressure regulating valve 22 to realize the adjustment of the gas pressure value in the mixed tank 3-1.

The material of the mixing tank 3-1 is 304 stainless steel, and an overpressure automatic emptying valve and a mechanical automatic drain valve are arranged, so that the pressure relief and discharge of gas and the automatic discharge of accumulated liquid in the mixing tank 3-1 are realized. The specific structure is shown in fig. 2 and 3: comprises an upper end cover 1-1, a tank body 1-2 and a lower end cover 1-3 which are connected in sequence through bolts and are used for gas humidification, gas-liquid separation and uniform mixing. The fuel cell stack gas inlet device is characterized in that an air inlet channel 1-2-1 and an oxygen inlet channel 1-2-2 are arranged on one side of the side wall of the tank body 1-2 along the tangential direction, a fuel cell stack tail gas inlet channel 1-2-3 is arranged on one side of the side wall along the tangential direction, a filter 3-2 is made of 316 stainless steel, and a filter layer micropore diameter is 2 microns and is connected with an upper end cover 1-1 through bolts for filtering mixed gas. The pressure sensor 3-3 and the oxygen concentration sensor 3-4 are connected with the upper end cover 1-1 of the mixing tank through threads, are arranged in the drift diameter of the filter 3-2 and are used for monitoring the pressure and the concentration of the mixed gas. The overpressure evacuation valve 3-5 is a mechanical valve, is connected with the upper end cover 1-1 of the mixing tank through threads, and is used for automatically evacuating mixed gas overpressure. The liquid collector 3-6 is made of 316 stainless steel and is connected with the mixed irrigation lower end cover 1-3 through bolts. The liquid level switch 3-7 and the electromagnetic valve 3-8 are connected with the liquid collector 3-6 through threads, and the liquid level switch 3-7 feeds collected signals back to the electromagnetic valve 8 to discharge liquid water in the liquid collector 3-6. Under the working state, tail gas of electrochemical reaction at the cathode of the pile, air and oxygen enter from an air inlet channel in the tangential direction of the mixing tank 3-1, and form cyclone under the guidance of the inner wall of the tank body 1-2, so that on one hand, the tail gas, the air and the oxygen are uniformly mixed, on the other hand, liquid water in mixed gas generates centrifugal motion and falls on the inner wall of the tank body 1-2, and flows to the bottom of the mixing tank 3-1 under the action of gravity, and the gas-water separation is realized. After the liquid water deposited in the liquid collector 3-6 at the bottom of the mixing tank 3-1 is evaporated and vaporized, the mixed gas is humidified, when the liquid water deposited in the liquid collector 3-6 is excessive, the liquid level switch 3-7 is switched on, the electromagnetic valve 3-8 is opened, and the liquid water is discharged out of the liquid collector 3-6. The oxygen concentration sensor 3-4 arranged on the upper end cover 1-1 of the mixing irrigation is used for monitoring the concentration of mixed gas, and can feed collected signals back to an electric valve bank on an air and oxygen supply pipeline, so that the air inflow of air is increased when the oxygen concentration is high, the air inflow of oxygen is reduced, and vice versa when the oxygen concentration is low. The pressure sensor 3-3 arranged on the upper end cover 1-1 of the mixing tank is used for monitoring the pressure of the mixed gas, the overpressure evacuation valve 3-5 is used for automatically evacuating the mixed gas under overpressure, and the filter 3-2 filters out impurities in the mixed gas on one hand and performs secondary water diversion on liquid water in the mixed gas on the other hand.

The gas-liquid separator 32 is provided with a filter and a mechanical automatic drain valve, wherein the oxygen concentration sensor a and the oxygen concentration sensor 3-4 can be the same, and the pressure sensor b and the pressure sensor 3-3 can be the same.

The pulse opening time of the pulse electromagnetic valve 33 is 50ms, and the pulse electromagnetic valve is used for periodically discharging excessive impurity gas in the mixed gas.

The technical principle of the present invention is explained in conjunction with the system structure of the present invention as follows:

in the working state, compressed air generated by the air compressor 12 is cooled by the intercooler 13 and then enters the mixing tank 3-1; high-pressure oxygen stored in an oxygen tank 21 enters a mixing tank 3-1 through an electric pressure regulating valve 22 and a flow controller 23; the tail gas of the electrochemical reaction of the fuel cell stack is subjected to gas-liquid separation through a gas-liquid separator 32, and then is pressurized through a circulating pump 34 and enters a mixing tank 3-1; the compressed air, oxygen and the fuel cell tail gas are uniformly mixed in the blending tank 3-1.

Air compressor machine 12, circulating pump 34 adopt inverter motor to adjust the rotational speed to the flow of control air and fuel cell tail gas, oxygen flow passes through flow controller 23 and adjusts, and according to the signal that comes from oxygen concentration sensor a, the flow of adjustment air compressor machine 12, circulating pump 34 and flow controller 23 obtains the mixed gas who sets for oxygen concentration: in the operation process, once the oxygen concentration in the mixed gas deviates from the set value, the oxygen concentration sensor a immediately feeds back and adjusts the flow of the air compressor 12, the circulating pump 34 and the oxygen flow controller 23, thereby realizing the adjustment of the oxygen concentration in the mixed gas.

The pressure of the mixed gas is adjusted by the air compressor 12 and the electric pressure regulating valve 22, and the air compressor 12 and the electric pressure regulating valve 22 are adjusted according to the signal from the pressure sensor b to obtain the mixed gas with the set pressure: in the operation process, once the mixed gas pressure is deviated from the set value negatively, the pressure sensor b immediately feeds back and adjusts the air compressor 12 and the pressure regulating valve 22, thereby realizing the adjustment of the mixed gas pressure value; if overpressure occurs, the overpressure emptying valve on the mixing tank 3-1 is immediately decompressed.

After saturated water vapor in the tail gas of the fuel cell enters the mixing tank 3-1, humidifying the mixed gas, carrying out gas-water separation on liquid water in the mixed gas in the mixing tank, depositing the liquid water at the bottom of the mixing tank 3-1, and discharging the liquid water through an automatic water discharge valve arranged at the bottom of the mixing tank 3-1.

The above-described embodiments are merely illustrative of the principles and effects of the present invention, and some embodiments may be applied, and it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the inventive concept of the present invention, and these embodiments are within the scope of the present invention.