阅读说明：本技术 一种带能量回收功能的燃料电池罗茨式空压机 (Take fuel cell roots formula air compressor machine of energy recuperation function ) 是由 钱星 徐明星 陈雷雷 易正根 于 2019-03-25 设计创作，主要内容包括：本发明提供了一种带能量回收功能的燃料电池罗茨式空压机,以克服目前燃料电池用空压机存在的加工成本高、电机转速要求高、存在喘振堵塞风险、效率低下等问题；本发明所述的一种带能量回收功能的燃料电池罗茨式空压机,采用罗茨式空压机作为压缩核心部件,罗茨式空压机的优点在于加工工艺要求低,但是单独采用罗茨式空压机存在效率不高的问题,因此本发明配合罗茨式膨胀机,水冷直流电机连接罗茨式空压机和罗茨式膨胀机,可回收电堆排气的能量,进一步提高效率,克服了单独使用罗茨式空压机低效的缺点。(The invention provides a Roots type air compressor with an energy recovery function for a fuel cell, which aims to solve the problems of high processing cost, high requirement on the rotating speed of a motor, surging and blocking risks, low efficiency and the like of the conventional air compressor for the fuel cell; the Roots-type air compressor with the energy recovery function for the fuel cell has the advantages that the Roots-type air compressor is adopted as a compression core component, the Roots-type air compressor is low in processing requirement, but the problem of low efficiency exists when the Roots-type air compressor is adopted independently, so that the Roots-type air compressor is matched with the Roots-type expander, the water-cooling direct-current motor is connected with the Roots-type air compressor and the Roots-type expander, the energy of stack exhaust can be recovered, the efficiency is further improved, and the defect of low efficiency when the Roots-type air compressor is used.)

1. A fuel cell Roots air compressor with an energy recovery function is characterized by comprising a water-cooling direct current motor (12) with adjustable rotating speed, wherein an output shaft at the front part of the water-cooling direct current motor (12) is connected with an air compressor (5) through a gear box (10) with a transmission gear (20), and an input shaft at the rear part of the water-cooling direct current motor (12) is connected with an expander (13) through the gear box (10) with the transmission gear (20);

the structure of the air compressor (5) and the structure of the expander (13) are completely the same, and the air compressor and the expander both comprise a hollow shell (4) with an opening at the front end and a closed rear end, the rear end surface of the shell (4) is fixedly connected with the front end surface of a box body of the gear box (10), the opening at the front end of the shell (4) is covered by an end cover (16), the front part of the end cover (16) is fixedly connected with a hollow gear box cover cap (1) with an opening at the front end and a closed rear end, a No. 1 rotor (6) is arranged above an internal cavity of the shell (4), a No. 2 rotor (17) is arranged below the internal cavity of the shell (4), the shapes and the structures of the No. 1 rotor (6) and the No. 2 rotor (17) are completely the same, and the gaps of the two rotors are arranged in the internal cavity of the shell (4), the rear end of a No. 1 rotor shaft (8) of the No. 1 rotor (6) is, the front part of a No. 1 rotor shaft (8) is supported in a through hole at the upper part of an end cover (16) through a No. 1 rotor front end bearing (3), the front end of the No. 1 rotor shaft (8) passes through the end cover (16) and is connected with a No. 1 helical gear (2) arranged in a gearbox cover (1), the rear part of a No. 2 rotor shaft (19) of a No. 2 rotor (17) is supported in a through hole at the lower part of the rear wall of a shell (4) through a No. 2 rotor rear end bearing (18), the rear end of the No. 2 rotor shaft (19) passes through a through hole at the lower part of the rear wall of the shell (4) and is connected with a gear (20) in the gearbox (10) after a through hole at the lower part of the front wall of a box body of the gearbox (10), the front part of the No. 2 rotor shaft (19) is supported in a through hole at the lower part of the end cover (16) through a No. 2 rotor front end bearing (15), and the front end of the No. 2 rotor shaft (19), the No. 1 helical gear (2) is meshed with the No. 2 helical gear (14), the middle part of the right side wall of the shell (4) is provided with an air inlet (42) communicated with the inner cavity of the shell (4), and the middle part of the left side wall of the shell (4) is provided with an air outlet (41) communicated with the inner cavity of the shell (4);

the rear wall of a shell (4) of an air compressor (5) is fixedly connected with the front part of a shell of a water-cooling direct current motor (12) through a box body of a gear box (10), a transmission gear (20) in the air compressor (5) is meshed with a shaft gear (11) on an output shaft of the water-cooling direct current motor (12), the rear wall of the shell (4) of an expander (13) positioned at the rear part of the water-cooling direct current motor (12) is fixedly connected with the rear part of the shell of the water-cooling direct current motor (12) through the box body of the gear box (10), and the transmission gear (20) in the expander (13) is meshed with the shaft gear (11) on an input shaft of the water-cooling direct current motor (12).

2. The roots-type air compressor with energy recovery function for fuel cell as claimed in claim 1, wherein the longitudinal section of the cavity inside the housing (4) is elliptical, and the longitudinal sections of the rotors No. 1 (6) and No. 2 (17) are elliptical.

3. The Roots-type air compressor with the energy recovery function for the fuel cell as recited in claim 1, wherein the air inlet (42) of the air compressor (5) is connected to the air outlet of an air filter (23) through a pipe, the air inlet of the air filter (23) is communicated with the outside atmosphere, the air outlet (41) of the air compressor (5) is communicated to the air inlet of an intercooler (24) through a pipe, the air outlet of the intercooler (24) is communicated to the air inlet of a first air passage of a humidifier (21) through a pipe, the air outlet of the first air passage of the humidifier (21) is communicated to the air inlet of a fuel cell stack (22) through a pipe, the air outlet of the fuel cell stack (22) is communicated to the air inlet of a second air passage of the humidifier (21) through a pipe, and the air outlet of the second air passage of the humidifier (21) is communicated to the air inlet (42) of the expander (13) through a pipe, the air outlet of the expander (13) is communicated with the outside atmosphere.

4. The roots-type air compressor with energy recovery function for fuel cell as claimed in claim 1, wherein the shaft gear (11) and the transmission gear (20) are helical gears to reduce the meshing noise.

5. The roots-type air compressor with energy recovery function for fuel cell as claimed in claim 1, wherein the gear box (10) contains lubricating oil, and an oil seal (9) is installed between the No. 2 rotor shaft (19) and the through hole of the front wall of the casing of the gear box (10).

6. The roots-type air compressor with the energy recovery function for the fuel cell as claimed in claim 1, 2, 3, 4 or 5, wherein the rotor cavity (61) is axially opened at the position above and below the rotor shaft (8) No. 1 in the rotor (6) No. 1, and the rotor cavity (61) is axially opened at the position above and below the rotor shaft (19) No. 2 in the rotor (17) No. 2, so as to reduce the weight of the rotor (6) No. 1 and the rotor (17) No. 2.

Technical Field

The invention belongs to the field of fuel cell engines, relates to an air compressor for a proton exchange membrane fuel cell, and particularly relates to a Roots type air compressor for a fuel cell with an energy recovery function.

Background

For Proton Exchange Membrane Fuel Cells (PEMFCs), it is necessary to pressurize the air as needed. On the one hand, the power density of the fuel cell can be increased, and on the other hand, the oxygen partial pressure influences the gibbs free energy in the chemical reaction, thereby influencing the efficiency limit of the fuel cell. Relevant research shows that the consumed power of the fuel cell air pressure pump is about 20-30% of the output power, and is a large energy consumer in a fuel cell auxiliary system. Increasing the efficiency of the air compressor can improve the efficiency of the entire fuel cell system.

There are three main types of air compressors for fuel cells: roots, twin screw and centrifugal.

The invention relates to a sealed compressor for a fuel cell (publication number: CN208330739A), belonging to a double-screw air compressor, wherein the double-screw compressor is used as an air compression part, and a motor is connected with the double-screw air compressor in a gear transmission way; the invention discloses a screw compression-expansion unit for a fuel cell automobile (publication number: CN1702899A), which belongs to a double-screw air compressor. The double-screw air compressor has the disadvantages of high process requirement, special machine tool machining, high cost and heavy weight.

The invention discloses an air compressor for a fuel cell (publication number: CN106837789A), which belongs to a Roots type air compressor, wherein the Roots type air compressor is used as an air compression part, and a motor is connected with the Roots type air compressor in a gear transmission mode. The Roots air compressor has the advantages of low processing technology requirement, low cost, low rotating speed, low motor response requirement and low total cost. But the problem of low efficiency exists in the roots type air compressor of adopting alone.

The centrifugal air compressor has the defects of high rotating speed, generally more than one hundred thousand revolutions per minute and high technical requirement on a motor. At present, the technology of the ultra-high speed motor is not mature at home, foreign countries are needed, and meanwhile, the control of the centrifugal air compressor is relatively complex, so that the overall cost is very high, meanwhile, the centrifugal air compressor has the risks of surging and blocking, the flow range is narrow, and the running is risky.

Disclosure of Invention

In order to overcome the problems in the prior art and solve the problems of high processing cost, high requirement on the rotating speed of a motor, risk of surging and blockage, low efficiency and the like of the conventional air compressor for the fuel cell, the invention provides the roots type air compressor for the fuel cell with the energy recovery function, wherein the roots type compressor is used as an air compression part, the motor is connected with the roots type air compressor in a gear transmission mode and matched with the roots type expander to recover the energy exhausted by a stack, the efficiency is further improved, and the defect of low efficiency of the roots type air compressor which is used independently is overcome.

The invention is realized by adopting the following technical scheme:

a fuel cell Roots air compressor with an energy recovery function is characterized by comprising a water-cooling direct current motor with adjustable rotating speed, wherein an output shaft at the front part of the water-cooling direct current motor is connected with an air compressor through a gear box with a transmission gear, and an input shaft at the rear part of the water-cooling direct current motor is connected with an expander through a gear box with a transmission gear;

the structure of the air compressor and the expander is completely the same, the air compressor and the expander both comprise a hollow shell with an opening at the front end and a closed rear end, the rear end surface of the shell is fixedly connected with the front end surface of a box body of the gear box, the opening at the front end of the shell is covered by an end cover, the front part of the end cover is fixedly connected with a hollow gear box cover with an opening at the front end and a closed rear end, a No. 1 rotor is arranged above the inner cavity of the shell, a No. 2 rotor is arranged below the inner cavity of the shell, the shape and the structure of the No. 1 rotor and the No. 2 rotor are completely the same, the No. 1 rotor and the No. 2 rotor are arranged in the inner cavity of the shell in a clearance manner, the rear end of a No. 1 rotor shaft of the No. 1 rotor is supported in a through hole at the upper part of the rear wall of the shell by a No. 1 rotor front end bearing, the front end of the No., the rear part of a No. 2 rotor shaft of a No. 2 rotor is supported in a through hole at the lower part of the rear wall of a shell through a No. 2 rotor rear end bearing, the rear end of the No. 2 rotor shaft passes through the through hole at the lower part of the rear wall of the shell and the through hole at the lower part of the front wall of a box body of a gear box and then is connected with a gear in the gear box, the front part of the No. 2 rotor shaft is supported in the through hole at the lower part of an end cover through a No. 2 rotor front end bearing, the front end of the No. 2 rotor shaft passes through the through hole at the lower part of the end cover and is connected with a No. 2 helical gear arranged in a cover cap of the gear box, the No. 1 helical gear is meshed with the No. 2;

the rear wall of the shell of the air compressor is fixedly connected with the front part of the shell of the water-cooling direct current motor through a box body of a gear box, a transmission gear in the air compressor is meshed with a shaft gear on an output shaft of the water-cooling direct current motor, the rear wall of the shell of the expansion machine positioned at the rear part of the water-cooling direct current motor is fixedly connected with the rear part of the shell of the water-cooling direct current motor through the box body of the gear box, and the transmission gear in the expansion machine is meshed with the shaft gear on an input shaft of the.

The further technical scheme comprises the following steps:

the longitudinal section of the cavity in the shell is oval, and the longitudinal sections of the No. 1 rotor and the No. 2 rotor are oval.

The air inlet of an air compressor is connected with the air outlet of an air filter through a pipeline, the air inlet of the air filter is communicated with the external atmosphere, the air outlet of the air compressor is communicated with the air inlet of an intercooler through a pipeline, the air outlet of the intercooler is communicated with the air inlet of a first air passage of a humidifier through a pipeline, the air outlet of the first air passage of the humidifier is communicated with the air inlet of a fuel cell stack through a pipeline, the air outlet of the fuel cell stack is communicated with the air inlet of a second air passage of the humidifier through a pipeline, the air outlet of the second air passage of the humidifier is communicated with the air inlet of an expander through a pipeline, and the air outlet of the expander is communicated with.

The shaft gear and the transmission gear are both helical gears to reduce meshing noise.

Lubricating oil is arranged in the gear box, and an oil seal is arranged between the No. 2 rotor shaft and a through hole in the front wall of the box body of the gear box.

The part of the No. 1 rotor above and below the No. 1 rotor shaft is provided with a rotor cavity along the axial direction, and the part of the No. 2 rotor above and below the No. 2 rotor shaft is provided with a rotor cavity along the axial direction, so that the weight of the No. 1 rotor and the No. 2 rotor is reduced.

Compared with the prior art, the invention has the beneficial effects that:

1. the roots type air compressor with the energy recovery function for the fuel cell provided by the invention adopts the roots type air compressor, and solves the problems of high processing cost, high requirement on the rotating speed of a motor, risk of surge and blockage, low efficiency and the like of the conventional air compressor for the fuel cell.

2. Compared with a single Roots air compressor and a Roots expander, the Roots air compressor with the energy recovery function for the fuel cell provided by the invention has the advantages that the waste gas energy of the electric pile is recovered, and the efficiency is improved.

Drawings

The invention is further described with reference to the accompanying drawings in which:

fig. 1 is a schematic structural sectional view of a roots-type air compressor with an energy recovery function for a fuel cell according to the present invention;

fig. 2 is a schematic structural cross-sectional view of a housing and rotors 1 and 2 in the housing of a roots-type air compressor with an energy recovery function for a fuel cell according to the present invention;

FIG. 3 is a schematic structural diagram of a Roots-type air compressor with an energy recovery function for a fuel cell applied to an air system of the fuel cell according to the present invention;

in the figure: 1. the motor comprises a gear box cover, a No. 2.1 helical gear, a No. 3.1 rotor front end bearing, a No. 4 shell, a No. 5 air compressor, a No. 6.1 rotor, a No. 7.1 rotor rear end bearing, a No. 8.1 rotor rotating shaft, a No. 9 oil seal, a No. 10 gear box, a No. 11 shaft gear, a No. 12 water-cooled direct current motor, a No. 13 expander, a No. 14.2 helical gear, a No. 15.2 rotor front end bearing, a No. 16 end cover, a No. 17.2 rotor, a No. 18.2 rotor rear end bearing, a No. 19.2 rotor rotating shaft, a No. 20 transmission gear, a No. 21 humidifier, a No. 22 fuel cell pile, a No. 23 air filter, a No. 24 intercooler, a No. 41 exhaust.

Detailed Description

The invention is described in detail below with reference to the attached drawing figures:

the invention provides a fuel cell roots type air compressor with an energy recovery function, which comprises a water-cooling direct current motor 12 with adjustable rotating speed, wherein an output shaft at the front part of the water-cooling direct current motor 12 is connected with an air compressor 5 through a gear box 10 with a transmission gear 20, and an input shaft at the rear part of the water-cooling direct current motor 12 is connected with an expander 13 through the gear box 10 with the transmission gear 20;

the air compressor 5 and the expander 13 have the same structure, and both comprise a hollow shell 4 with an opening at the front end and a closed rear end, the rear end surface of the shell 4 is fixedly connected with the front end surface of the box body of the gear box 10, the opening at the front end of the shell 4 is covered by an end cover 16, and the hollow gear box cover 1 with a closed front end and a closed rear end is fixedly connected in front of the end cover 16.

As shown in fig. 1 and 2, a rotor No. 1 is arranged above the cavity in the housing 4, a rotor No. 2 is arranged below the cavity in the housing 4, the rotor No. 1 and the rotor No. 2 are identical in shape and structure and are arranged in the cavity in the housing 4 with a gap therebetween, the longitudinal section of the cavity in the housing 4 is oval, and the longitudinal sections of the rotor No. 1 and the rotor No. 2 17 are oval. The parts of the No. 1 rotor 6 above and below the No. 1 rotor shaft 8 are provided with rotor cavities 61 along the axial direction, and the parts of the No. 2 rotor 17 above and below the No. 2 rotor shaft 19 are provided with rotor cavities 61 along the axial direction, so that the weight of the No. 1 rotor 6 and the weight of the No. 2 rotor 17 are reduced.

As shown in FIG. 1, the rear end of the No. 1 rotor shaft 8 of the No. 1 rotor 6 is supported in a through hole in the upper part of the rear wall of the housing 4 through a No. 1 rotor rear end bearing 7, the front part of the No. 1 rotor shaft 8 is supported in a through hole in the upper part of the end cover 16 through a No. 1 rotor front end bearing 3, the front end of the No. 1 rotor shaft 8 is connected to a No. 1 helical gear 2 provided in the gearbox cover 1 through the end cover 16, the rear part of the No. 2 rotor shaft 19 of the No. 2 rotor 17 is supported in a through hole in the lower part of the rear wall of the housing 4 through the end cover 16, the rear end of the No. 2 rotor shaft 19 is connected to a gear 20 inside the gearbox 10 after passing through a through hole in the lower part of the rear wall of the housing 4 and a through hole in the lower part of the front wall of the gearbox 10, the front part of the No. 2 rotor shaft 19 is supported in a through hole in the lower part of the end cover 16 through a No. 14, a No. 1 bevel gear 2 is meshed with a No. 2 bevel gear 14, the middle part of the right side wall of the shell 4 is provided with an air inlet 42 communicated with the inner cavity of the shell 4, and the middle part of the left side wall of the shell 4 is provided with an air outlet 41 communicated with the inner cavity of the shell 4; lubricating oil is filled in the gear box 10, and an oil seal 9 is arranged between the No. 2 rotor shaft 19 and a through hole in the front wall of the box body of the gear box 10.

The rear wall of the shell 4 of the air compressor 5 is fixedly connected with the front part of the shell of the water-cooling direct current motor 12 through a box body of a gear box 10, a transmission gear 20 in the air compressor 5 is meshed with a shaft gear 11 on an output shaft of the water-cooling direct current motor 12, the rear wall of the shell 4 of the expansion machine 13 is fixedly connected with the rear part of the shell of the water-cooling direct current motor 12 through the box body of the gear box 10, and the transmission gear 20 in the expansion machine 13 is meshed with the shaft gear 11 on an input shaft of the water-cooling direct current motor 12. The shaft gear 11 and the transmission gear 20 are helical gears to reduce meshing noise.

As shown in fig. 3, the roots-type air compressor with energy recovery function for fuel cell according to the present invention is applied to the air system of fuel cell, an air inlet 42 of the air compressor 5 is communicated with an air outlet of an air filter 23 through a pipeline, the air inlet of the air filter is communicated with the outside atmosphere, an air outlet 41 of the air compressor 5 is communicated with an air inlet of an intercooler 24 through a pipeline, an air outlet of the intercooler 24 is communicated with an air inlet of a first air passage of a humidifier 21 through a pipeline, an air outlet of the first air passage of the humidifier 21 is communicated with an air inlet of a fuel cell stack 22 through a pipeline, an air outlet of the fuel cell stack 22 is communicated with an air inlet of a second air passage of the humidifier 21 through a pipeline, an air outlet of the second air passage of the humidifier 21 is communicated with an air inlet 42 of the expander 13 through a pipeline, and an air outlet of the expander 13 is communicated with.

The water-cooled direct current motor 12 drives the air compressor 5 to operate, air enters the air compressor 5 through the air filter 23, and the air enters the intercooler 24 after being compressed by the air compressor 5 and enters the fuel cell stack 22 through the humidifier 21. Air is subjected to chemical reaction in a fuel cell stack 22 to generate electric energy and product water, the residual tail gas with certain pressure and temperature enters an expander 13 through a humidifier 21, the tail gas drives the expander 13 to recover and convert kinetic energy in the tail gas movement process into mechanical energy, and the mechanical energy is conveyed to a compressor 5 through a water-cooling direct current motor 12. The tail gas after work is done in the expander 13 is discharged to the atmosphere.