KR101934574B1 - Sensor flow control unit and flow measurement device using the same - Google Patents

Abstract

The present invention relates to a sensor flow rate control unit capable of controlling the flow rate of fuel or gas moving to a bypass pipe for measuring the flow rate of fuel or gas for the operation of the fuel cell system and a flow rate measuring device using the same .
The present invention relates to a sensor flow rate control unit for regulating the flow rate of a flow of a fluid that is branched and flows into and out of a mass flow rate sensor, the sensor flow rate control unit comprising: a main body; A sensor flow rate outlet formed to penetrate the main body and configured to guide the flow of the fluid, and at least one of the sensor flow rate inlet and the sensor flow rate outlet, Accordingly, it is an object of the present invention to provide a sensor flow rate control unit including a flow rate control channel in which the flow rate of the fluid is controlled.

Description

A sensor flow control unit and a flow measurement device using the same,

The present invention relates to a sensor flow rate control unit and a flow rate measuring apparatus using the same. More particularly, the present invention relates to a fuel flow meter for measuring a flow rate of fuel or gas for operation of a fuel cell system, To a sensor flow rate control unit capable of controlling the flow rate of a gas and a flow rate measuring apparatus using the same.

The PEMFC (Proton Exchange Membrane Fuel Cell) system uses a polymer membrane with hydrogen ion exchange properties as an electrolyte, and uses an oxidant gas containing hydrogen and a fuel gas containing air or oxygen to perform an electrochemical reaction To generate electricity and heat.

Therefore, in principle, since the thermo-mechanical limit of the heat engine is not limited, the power generation efficiency is higher than that of the conventional power generation device, and the environmental problem is relatively low due to no pollution and no noise. In addition, the fuel cell can be manufactured in various capacities, and the fuel cell can be easily installed in the power demand site, thereby reducing the initial investment cost of the power transmission /

The flow rate of fuel or gas is measured to control the flow rate of the fuel or gas for driving the fuel cell system in the course of driving the fuel cell system.

In order to achieve this, a bypass channel is formed instead of a main flow channel to which fuel or gas is supplied, and a sensor for measuring a flow rate is disposed in the bypass channel. The inlet and outlet ends of the bypass channel are connected to the main flow channel .

This is because the mass flow rate that can be measured by the sensor is physically fixed, so that the flow rate can not be measured by the sensor.

In the conventional production method, the control of the fuel or gas, which is branched from the main flow channel to the bypass channel, is performed by adjusting the diameter of the bypass channel. However, in the above method, the diameter of the bypass channel must be adjusted for each branching flow rate, and the product must be manufactured separately.

Korean Patent Laid-Open Publication No. 10-2014-0029883 (entitled Integrated Control System for Fuel Cell Vehicle, published on Mar. 11, 2014)

The object of the present invention is to provide a fuel cell system including a flow control unit capable of controlling a flow rate of a fuel or a gas moving to a bypass pipe for measuring the flow rate of fuel or gas for the operation of the fuel cell system And to provide a flow rate measuring apparatus.

According to an aspect of the present invention, there is provided a sensor flow rate control unit for controlling a flow rate of a flow that flows into and flows out of a mass flow rate sensor, the flow rate control unit comprising: a body; A sensor flow rate inflow portion formed to penetrate the main body and guiding the outflow of the fluid and a sensor flow rate inflow portion penetratingly inserted into at least one of the sensor flow rate inflow portion and the sensor flow rate outflow portion, And a flow rate control line through which the fluid moves, the flow rate of the fluid being controlled according to the length.

Here, the sensor flow rate inflow portion and the sensor flow rate outflow portion are formed at a predetermined depth from the lower end of the main body, and include at least a first hole in which at least a part of the flow rate control pipe is located, A second hole through which the lower end surface is fixedly coupled to the end of the flow rate control conduit and a lower end surface of the second hole from the upper surface of the first hole, And may include a third hole.

Here, the longer the length of the flow rate control pipe located in the first hole, the more the fluid flowing from the flow channel to the bypass pipe can be reduced.

According to another aspect of the present invention, there is provided an apparatus for supplying a fluid, comprising: a pump for supplying a fluid; a flow channel block having a flow channel for receiving fluid output from the pump; And a bypass block disposed between the flow channel block and the bypass block and adapted to control a flow rate of a fluid flowing in the bypass pipe among the fluids moving in the flow channel block, A mass flow rate sensor for measuring a flow rate of the fluid moving in the bypass pipe and located inside the bypass pipe; and a flow rate sensor for measuring a flow rate of the fluid, based on the flow rate measured from the MEMS mass flow rate sensor, And a controller for controlling the output of the flow rate measuring device.

Here, the pump is constituted by a diaphragm pump, the fluid is fuel or air, and the fuel may be liquid natural gas.

Here, the controller is configured as a PID controller, and can perform a digital signal processing process for stabilizing a pulsating flow.

The present invention has the following effects.

First, the sensor flow rate control unit includes a sensor flow rate inlet formed in the body of the sensor flow rate control unit and a flow rate control pipe fixedly coupled to the sensor flow rate outlet. The length of the flow rate control pipe located inside the sensor flow rate inlet and the sensor flow rate outlet is adjusted There is an advantage in that the flow rate of the fluid that is branched from the flow channel and moves to the bypass pipe can be adjusted.

Secondly, since it is possible to omit production of a separate block for controlling the flow rate, the production cost can be lowered, the production efficiency can be increased, the flow rate of the fluid according to the sensor can be finely adjusted, and more accurate measurement becomes possible.

1 is a view showing a sensor flow rate control unit according to the present invention.
FIG. 2 is a view showing various embodiments of the sensor flow rate control unit of FIG. 1. FIG.
3 is a view showing a flow rate measuring apparatus according to the present invention.
Fig. 4 is a schematic view of the flow measurement device of Fig. 1. Fig.
FIG. 5 is a view showing flow data measured by the measuring unit of the flow measuring apparatus of FIG. 4 and flow data measured by the signal processing unit by the digital processing of the flow measured by the measuring unit.

Hereinafter, preferred embodiments of the present invention in which the above-mentioned problems to be solved can be specifically realized will be described with reference to the accompanying drawings. In describing the embodiments, the same names and the same symbols are used for the same configurations, and additional description thereof will be omitted in the following.

The sensor flow rate control unit according to the present invention will now be described with reference to FIGS. 1 and 2. FIG.

1 and 2, the sensor flow rate control unit according to the present invention includes a main body 110, a sensor flow rate inlet 110a, a sensor flow rate outlet 110b, and a flow rate control channel 120 .

The body 110 guides the flow of fluid diverted from the flow channel (320 in FIG. 4) to the bypass tube (220 in FIG. 4), and the sensor flow inlet 110a and the sensor flow outlet 110b are formed in the main body 110. [

The sensor flow inlet 110a is formed through the main body 110 and guides the fluid flowing from the flow channel 320 among the fluid. Wherein the fluid may be fuel or air, and the fuel may be liquid natural gas.

The sensor flow outlet 110b is formed through the main body 110 and flows through the bypass pipe 220 to the flow channel 320 through the sensor flow outlet 110b. do.

The flow rate control line 120 is inserted into at least one of the sensor flow rate inlet 110a and the sensor flow rate outlet 110b, and the flow rate of the fluid is adjusted according to the length.

Specifically, the sensor flow rate inflow portion 110a and the sensor flow rate outflow portion 110b include a first hole 111, a second hole 112, and a third hole 113.

The first hole 111 is formed at a predetermined depth from the lower end of the main body 110. At least a part of the flow control pipe 120 is located inside the first hole 111, 111 do not penetrate the whole of the main body 110. The diameter of the first hole 111 corresponds to the diameter of the inlet port 321 and the outlet port 322 formed in the flow channel block 310 (310 of FIG. 3) in which the flow channel 320 is formed.

The second hole 112 is formed at a predetermined depth from the upper end of the main body 110 and the lower end surface of the second hole 112 is fixedly coupled to one end of the flow control pipe 120. The lower end surface of the second hole 112 and the outer surface or the end of the one end of the flow control pipe 120 may be fixedly welded.

Of course, the method of fixedly connecting the lower end surface of the second hole 112 to one end of the flow control pipe 120 is not limited to welding, and the fluid for moving the sensor flow control unit according to the present invention may be connected to the flow control pipe It is possible to freely apply the method as long as it does not leak to a path other than the inside of the housing 120.

The predetermined depth of the second hole 112 is determined by the size of the O-ring mounted inside the second hole 112 after the lower end surface of the second hole 112 and the flow control pipe 120 are fixedly coupled And the sensor flow rate control unit according to the present invention can be freely changed according to the environment and the size in which it is used.

The third hole 113 is formed to penetrate from the upper end surface of the first hole 111 to the lower end surface of the second hole 112. At least a part of the flow control pipe 120 is connected to the third hole 113, (113) passes through. That is, one end of the flow control pipe 120 is fixedly coupled to the lower end surface of the second hole 112, and the other end of the flow control pipe 120 is positioned in the first hole 111, So that the regulating conduit 120 passes through the third hole 113.

The diameter of the third hole 113 is easily formed to be fixedly coupled to the lower end surface of the second hole 112 by the flow control pipe 120 and is larger than the outer diameter of the flow control pipe 120 .

The flow rate of the fluid according to the length of the flow control pipe 120 is controlled as follows.

For example, as shown in FIG. 2 (a) and FIG. 4, the length of the flow rate control pipe 120a located inside the sensor flow rate inflow portion 110a and the sensor flow rate outflow portion 110b is The resistance of the flow control pipe 120a is increased, so that a small amount of fluid is branched by the bypass pipe 220 and is moved.

On the contrary, as shown in FIG. 2B and FIG. 4, the length of the flow rate control pipe 120b located inside the sensor flow rate inflow portion 110a and the sensor flow rate outflow portion 110b is relatively short The resistance due to the flow rate control pipe 120b is reduced, so that a large amount of fluid is branched and moved to the bypass pipe 220. [

That is, even if the flow control pipe 120 is composed of the body 110, the first hole 111, the second hole 112, the third hole 113, and the flow control pipe 120, The amount of the fluid flowing through the flow rate regulating conduit 120 can be controlled by adjusting the length of the first hole 111.

Accordingly, since it is possible to omit production of a separate block for controlling the flow rate, the production cost can be lowered, the production efficiency can be increased, and the flow rate of the fluid according to the sensor can be finely adjusted.

The flow measuring apparatus according to the present invention will be described with reference to FIGS. 1 to 5. FIG.

1 to 5, a flow rate measuring apparatus according to the present invention includes a pump 400, a mass flow measurement body 110, a MEMS mass flow rate sensor 600, a controller 500, and a cover 900 .

The pump 400 supplies fluid to the reformer 700 through the mass flow measurement body 110, the fluid includes fuel and air, and the fuel may be liquid natural gas.

 The mass flow measurement body 110 includes a flow channel block 310, a bypass block 210, and a sensor flow rate regulator.

The flow channel block 310 is formed with a flow channel 320 for supplying the fluid output from the pump 400 to the reformer 700. A quick fastener 800) are coupled.

The flow channel 320 is formed to penetrate the flow channel block 310 and the fluid output from the pump 400 is supplied to the reformer 700.

The bypass block 210 has an inlet end and an outlet end connected to the flow channel block 310 and a bypass pipe 220 through which a part of the fluid moving in the flow channel block 310 branches and moves And the bypass pipe 220 is formed to measure the flow rate of the fluid.

The quick-fastener 800 and the mass flow rate measurement body 110 are preferably made of a material having chemical resistance to liquid natural gas (LNG), which is one of the fuels used in polymer electrolyte membrane fuel cells (PEMFC) .

For example, the quick-fastener 800 and the mass flow rate measuring body 110 may be made of a PPS (polyphenylene sulfide) material having heat resistance and high strength of 250 ° C. . Alternatively, the quick-fastener 800 and the mass flow rate measuring body 110 may be made of POM (Poly Oxy Methylene) resin. Since the POM resin material is relatively inexpensive to manufacture and has a shorter production time than the PPS material, The time required for manufacturing the mass flow measurement body 110 can be shortened.

The MEMS mass flow sensor 600 is a thin film type hot film sensor which is disposed inside the bypass tube 220 and is manufactured by MEMS technology. The hot film sensor has a high production cost of a hot wire mass flow sensor And the heat pipe exposed to the bypass pipe 220 are contaminated and the measurement accuracy is impaired, thereby making it possible to perform more precise measurement.

That is, the MEMS mass flow sensor 600 measures the flow rate of the fluid flowing through the bypass pipe 220, thereby determining the amount of fluid supplied to the flow channel 320 as a whole.

The controller 500 controls the output of the pump 400 based on the flow rate measured from the MEMS mass flow sensor 600. Specifically, the controller 500 includes a power unit (not shown), a measuring unit 540, A signal processing unit 520, a communication unit 510, and a control unit 530.

The power unit manages the entire mass flow rate measuring apparatus for a fuel cell according to the present invention and receives power input of 15 to 24 VDC, which is generally used in a general industrial field.

The power supplied from the power supply unit cuts off the noise generated in the external power environment through a separate filter, and converts the voltage into a voltage level required by each of the devices, thereby supplying clean power.

The measuring unit 540 transmits the analog measurement signal of the MEMS flow rate sensor 600, which measures the flow rate of the fluid flowing through the bypass pipe 220, to the signal processing unit 520.

The signal processor 520 includes main components such as an ADC, a DAC, an EEPROM, and an RS 485, and peripheral circuits around the MCU.

The signal processing unit 520 digitally processes the analog measurement signal of the fluid received from the measurement unit 540, and processes the signal according to the calibration value stored in the digitally processed measurement signal.

This is because it is possible to more accurately represent the dynamic change of the data by eliminating the noise of the data input to the measuring unit 540 and stabilizing the pulsating flow. In order to process the data at high speed in the signal processing unit 520, And the correction value stored in the signal processing unit 520 is as follows. ≪ tb > < TABLE >

In Equation (1), x [i] is an input signal, y [j] is an output signal, and M is a moving average number, that is,

For example, if the number of moving average M is 5 and RawData x [i] is obtained according to time, the moving average data y [i] is given as follows.

As described above, by performing the signal processing using the calibration value, the noise of the digital data transmitted from the measuring unit 540 can be removed, and the pulsation flow can be stabilized.

For example, as shown in FIG. 5A, the digitized data transmitted to the measuring unit 540 is subjected to signal processing through a method of stabilizing a pulsating flow by a method similar to the above-described process, The signal processing is performed as shown in FIG. 5 (b) when the moving average number M of the calibration values is 11. When the moving average number M of the calibration values is 51, signal processing is performed as shown in FIG. 5 (c) .

The control unit 530 controls the output of the pump 400 to control the flow rate of the fluid flowing through the flow channel 320 based on the flow rate measured from the MEMS mass flow sensor 600, The controller 530 may include a PID controller 500.

The communication unit 510 transmits a flow control command of the fluid delivered from the controller 530 from the pump 400. The communication unit 510 may be connected to the pump 400 by wire, LAN or the like.

As described above, the present invention is not limited to the above-described specific preferred embodiments, and various changes and modifications may be made by those skilled in the art without departing from the scope of the present invention as claimed in the claims. And such variations are within the scope of the present invention.

110:
110a: Sensor flow rate inlet
110b: sensor flow rate outlet
111: 1st hole
112: second hole
113: Third hole
120: Flow control pipe
210: Bypass block
220: Bypass pipe
310: Flow channel block
320: flow channel
321: Inlet
322: Outlet
400: pump
500: controller
510:
520: Signal processor
530:
540:
600: MEMS mass flow sensor
700: reformer
800: Quick fastener
900: cover

Claims (6)

A sensor flow rate adjusting unit mounted on a flow rate measuring apparatus having a flow channel and a bypass pipe and adapted to regulate a flow rate of a flow of fluid flowing into and out of a mass flow rate sensor,
A body guiding the movement of the fluid branched in the flow channel to the bypass tube;
A sensor flow rate inflow portion formed to penetrate through the main body and to guide inflow of the fluid;
A sensor flow rate outlet formed through the body to guide the fluid flow; And
And a flow rate control conduit inserted into at least one of the sensor flow rate inlet and the sensor flow rate outlet to move the fluid and adjust the flow rate of the fluid according to the length,
Wherein the sensor flow rate inflow portion and the sensor flow rate outflow portion are formed at a predetermined depth from a lower end of the main body and include at least a first hole in which at least a portion of the flow rate regulation pipe is located,
Wherein a resistance of the flow rate control conduit is increased as the length of the flow rate control conduit located in the first hole is longer and the fluid that is branched from the flow channel and moves to the bypass conduit is decreased. Control unit. The method according to claim 1,
Wherein the sensor flow rate inflow portion and the sensor flow rate outflow portion comprise:
A second hole penetrating from the upper end of the main body to a predetermined depth and having a lower end surface fixedly coupled to an end of the flow control pipe;
And a third hole penetrating from the upper end surface of the first hole to the lower end surface of the second hole, wherein at least a portion of the flow control pipe passes through the third hole. delete A pump for supplying fluid;
A flow channel block formed with a flow channel to receive the fluid output from the pump;
A bypass block in which a bypass pipe is formed in which a part of the fluid moving in the flow channel is branched and moved;
A sensor flow rate control unit according to claim 1 arranged between the flow channel block and the bypass block to adjust a flow rate of fluid flowing in the bypass pipe among the fluids moving through the flow channel block;
A MEMS mass flow rate sensor positioned inside the bypass pipe and measuring a flow rate of the fluid moving in the bypass pipe; And
And a controller for controlling an output of the pump based on a flow rate measured from the MEMS mass flow sensor. 5. The method of claim 4,
Wherein the pump comprises a diaphragm pump, the fluid is fuel or air,
Wherein the fuel is liquid natural gas. 5. The method of claim 4,
Wherein the controller comprises a PID controller and performs a digital signal processing process for stabilizing a pulsating flow.

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