KR102481988B1 - Method for detecting height of sediment in a pipe, method and apparatus for calculating flow rate using the same - Google Patents

Abstract

Disclosed are a method for detecting height of sediment in a pipe, and a method and a device for calculating a flow rate using the same. The device for calculating a flow rate comprises: an RF transmission and reception unit transmitting an RF (radio frequency) signal to the inside of the pipe and receiving the RF signals at different height; a sensor unit transmitting an ultrasonic signal or a radar signal into the pipe to measure a water level and flow speed of fluid flowing inside the pipe; and a control unit calculating height of the sediment deposited inside the pipe by using the RF signal and calculating a flow rate of the fluid flowing inside the pipe by using the height and flow speed of the sediment.

Description

Method for detecting height of sediment in a pipe, method and apparatus for calculating flow rate using the same}

The present invention relates to a technology for calculating the flow rate in a pipe, and more particularly, detects the height of the sediment in the pipe, detects the height of the sediment in the pipe, reflects the height of the detected sediment, and calculates the flow rate of the pipe. It relates to a method, a flow rate calculation method and apparatus using the same.

Pipes, such as drains or sewers, accumulate sediment over time.

Conventional systems for measuring flow rate measure flow rate by using both an ultrasonic sensor and a radar sensor. However, this system has a problem in that it cannot measure the height of the precipitate deposited in the pipe, thereby generating an error as much as the deposited precipitate, thereby generating an error in flow rate measurement.

Accordingly, a method in which a plurality of ultrasonic sensors are installed at different heights is used as a method for minimizing errors, but this also has a problem in that a large number of expensive ultrasonic sensors must be used.

Korea Patent Registration No. 10-0791319 (2008.01.03.)

The problem to be solved by the present invention is to determine the presence or absence of precipitate deposited inside the pipe, calculate the height of the precipitate if the precipitate exists, and then calculate the flow rate of the pipe by reflecting the calculated height of the precipitate. It is to provide a method for detecting the height of sediment in a pipe, a flow rate calculation method and device using the same.

In order to solve the above problems, the flow rate calculation device according to the present invention transmits a radio frequency (RF) signal to the inside of the pipe, and an RF transceiver for receiving the RF signal at different heights, and an ultrasonic signal to the inside of the pipe. Alternatively, the height of the precipitate deposited in the pipe is calculated using a sensor unit that transmits a radar signal to measure the level and flow rate of the fluid flowing inside the pipe and the RF signal, and the height of the precipitate and the flow rate are used to calculate the height of the precipitate. and a control unit for calculating the flow rate of the fluid flowing in the pipe.

In addition, the RF transceiver is installed at the top of the pipe and has a different distance from the RF transmitter for transmitting the RF signal to the inside of the pipe and the RF transmitter along the circumferential surface of the pipe, and the RF signal It includes a plurality of RF receivers individually receiving.

In addition, each of the plurality of RF receivers is characterized in that a path loss value, which is a loss value lost according to a transmission distance of the RF signal, increases by a predetermined ratio based on when the fluid is at a full water level.

In addition, each of the plurality of RF receivers is characterized in that the distance from the RF transmitter is increased in a zigzag order based on the center of the pipe.

In addition, the controller controls only the RF receiver receiving the RF signal to be in an on state and controls the remaining RF receivers to be in an off state so that signal interference between the plurality of RF receivers does not occur. do.

In addition, the control unit calculates path loss values for the plurality of RF receivers, respectively, when the pipe is full of the fluid, and a graph connecting the calculated path loss values forms one constant slope value. It is characterized in that it is determined that the precipitate does not exist when the branch includes a straight line.

In addition, the control unit calculates path loss values for the plurality of RF receivers, respectively, when the pipe is full of the fluid, and a graph connecting the calculated path loss values forms one constant slope value. It is characterized in that it is determined that the precipitate exists when a first straight line and a second straight line having a slope value smaller than the slope value of the first straight line are included.

In addition, the controller determines that the precipitate exists from the point where the first straight line and the second straight line intersect, and calculates the height of the precipitate using the determined result.

In addition, the control unit calculates path loss values for the plurality of RF receivers, respectively, when only a portion of the pipe is filled with the fluid and the fluid level is higher than the height at which the plurality of RF receivers are installed, It is characterized in that it is determined that the precipitate does not exist when the graph connecting the average values of the calculated path loss values includes a straight line having a constant slope value.

In addition, the control unit determines a path to the plurality of RF receivers when only a portion of the pipe is filled with the fluid and the level of the fluid is lower than the height at which at least one RF receiver among the plurality of RF receivers is installed. If the loss values are calculated, and the graph connecting the average values of the calculated path loss values includes a third straight line having a constant slope value and a fourth straight line having a slope value smaller than the slope value of the third straight line It is characterized in that it is determined that the precipitate does not exist.

In addition, the control unit calculates path loss values for the plurality of RF receivers, respectively, when only a portion of the pipe is filled with the fluid and the fluid level is higher than the height at which the plurality of RF receivers are installed, If the graph connecting the average values of the calculated path loss values includes a fifth straight line having a constant slope value and a sixth straight line having a slope value smaller than the slope value of the fifth straight line, it is determined that the precipitate exists. It is characterized by doing.

In addition, the controller determines that the precipitate exists from a point where the fifth straight line and the sixth straight line intersect, and calculates the height of the precipitate using the determined result.

In addition, the control unit determines a path to the plurality of RF receivers when only a portion of the pipe is filled with the fluid and the level of the fluid is lower than the height at which at least one RF receiver among the plurality of RF receivers is installed. A graph obtained by calculating loss values and connecting average values of the calculated path loss values is a seventh straight line having a constant slope value, an eighth straight line having a slope value smaller than the slope value of the seventh straight line, and It is characterized in that it is determined that the precipitate exists when a ninth straight line having a slope value smaller than the slope value of the eighth straight line is included.

In addition, the control unit determines that the fluid flows from a point where the seventh straight line and the eighth straight line intersect, and that the precipitate exists from a point where the eighth straight line and the ninth straight line intersect, and as a result of the determination It is characterized in that the height of the precipitate is calculated using.

In addition, the control unit calculates the volume of the precipitate using the height of the precipitate, and calculates the volume of the calculated precipitate reflected in the volume of the pipe when the pipe is full of the fluid. , It is characterized in that the flow rate is calculated using the calculated volume and the flow rate measured using the ultrasonic signal.

In addition, if only a part of the pipe is at the rainwater level in a state filled with the fluid, the volume of the precipitate is calculated using the height of the precipitate, and a volume obtained by reflecting the calculated volume of the precipitate to the volume of the pipe is calculated. It is characterized in that the flow rate is calculated using the measured volume and the flow rate measured using the radar signal.

The flow rate calculation method according to the present invention determines whether a precipitate deposited in a pipe is present or not using an RF signal by a flow rate calculation device, and if the precipitate exists, calculating a height of the precipitate, and the flow rate calculation device measures the precipitate and calculating the flow rate of the fluid using the height of the pipe and the flow rate of the fluid flowing inside the pipe.

According to an embodiment of the present invention, by determining the presence or absence of precipitate deposited inside the pipe using an RF signal and calculating the height of the precipitate when the precipitate exists, installation cost can be reduced because a large number of expensive ultrasonic sensors are not installed. savings can be made

In addition, according to an embodiment of the present invention, the user can check the accurate flow rate by calculating the flow rate of the fluid flowing in the pipe in which the volume of the precipitate is reflected using an ultrasonic signal or a radar signal.

1 is a configuration diagram for explaining a flow rate calculation system according to an embodiment of the present invention.
2 is a block diagram for explaining a flow rate calculating device according to an embodiment of the present invention.
3, 4, 5, and 6 are perspective views for explaining how an RF transceiver and a sensor unit are installed in a pipe according to an embodiment of the present invention.
7 is a diagram for explaining a process of measuring a fluid level by a sensor unit using an ultrasonic sensor according to an embodiment of the present invention.
8 is a diagram for explaining a process of measuring a flow rate at a full water level using an ultrasonic sensor by a sensor unit according to an embodiment of the present invention.
9 is a diagram for explaining a process of measuring a flow rate at a water level by a sensor unit using a radar sensor according to an embodiment of the present invention.
10 and 11 are diagrams for explaining a process of calculating the height of precipitate at the full water level using an RF transceiver by the flow rate calculating device according to an embodiment of the present invention.
12 and 13 are diagrams for explaining a process of calculating the height of precipitate from a rainwater level by using an RF transceiver by the flow rate calculating device according to an embodiment of the present invention.
14 is a flowchart for explaining a flow rate calculation method according to an embodiment of the present invention.
15 is a flowchart for explaining step S100 of FIG. 14 in detail.
16 is a flowchart for explaining step S200 of FIG. 14 in detail.
17 is a block diagram illustrating a computing device according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

In the present specification and drawings (hereinafter referred to as 'this specification'), redundant descriptions of the same components are omitted.

In addition, in this specification, when a component is referred to as being 'connected' or 'connected' to another component, it may be directly connected or connected to the other component, but another component in the middle It should be understood that may exist. On the other hand, in this specification, when a component is referred to as 'directly connected' or 'directly connected' to another component, it should be understood that no other component exists in the middle.

In addition, terms used in this specification are only used to describe specific embodiments and are not intended to limit the present invention.

Also, in this specification, a singular expression may include a plurality of expressions unless the context clearly indicates otherwise.

In addition, in this specification, terms such as 'include' or 'having' are only intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more It should be understood that the presence or addition of other features, numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Also in this specification, the term 'and/or' includes a combination of a plurality of listed items or any item among a plurality of listed items. In this specification, 'A or B' may include 'A', 'B', or 'both A and B'.

Also, in this specification, detailed descriptions of well-known functions and configurations that may obscure the subject matter of the present invention will be omitted.

1 is a configuration diagram for explaining a flow rate calculation system according to an embodiment of the present invention.

Referring to FIG. 1 , the flow rate calculation system 300 determines the presence or absence of precipitate deposited inside the pipe, and calculates the height of the precipitate when the precipitate is present. The flow rate calculation system 300 accurately calculates the flow rate of the corresponding pipe using the calculated height of the precipitate. Here, the pipe is a pipe through which the fluid flows, and includes a drain pipe, a sewage pipe, and the like, and the precipitate refers to a material included in the fluid and deposited on the lower part of the pipe. The flow rate calculation system 300 includes a flow rate calculation device 100 and a user terminal 200 .

The flow rate calculating device 100 calculates the height of the precipitate deposited in the pipe using a radio frequency (RF) signal. The flow rate calculating device 100 may calculate the height of the precipitate in different ways by distinguishing between a full water level in which the pipe is filled with fluid or an empty water level in which only a part of the pipe is filled with fluid. When the calculation of the height of the precipitate is completed, the flow rate calculating device 100 calculates the volume of the precipitate using the height of the precipitate and the volume of the pipe. At this time, the flow rate calculating device 100 may pre-store the volume of the pipe. The flow rate calculating device 100 calculates the flow rate by using the flow rate of the fluid and the volume of the pipe in which the volume of the precipitate is reflected. At this time, the flow rate calculating device 100 may measure the flow speed using an ultrasonic signal when the water level is full, and measure the flow speed using a radar signal when the water level is full.

The user terminal 200 is a terminal used by a user and monitors the flow rate of a pipe in conjunction with the flow rate calculating device 100 . The user terminal 200 monitors the sediment-related information (eg, sediment height, volume, etc.) and fluid-related information (eg, fluid type, flow rate, flow rate, etc.) from the flow rate calculation device 100. It can receive information and output the received information. At this time, the user terminal 200 may output a notification message when the flow rate of the fluid decreases below a preset standard so that the user can intuitively recognize the corresponding content. The user terminal 200 may include a smart phone, desktop, laptop, tablet PC, handheld computer, etc., but is not limited thereto.

Meanwhile, the flow rate calculation system 300 establishes a communication network 350 between the flow rate calculation device 100 and the user terminal 200 to allow communication between them. The communication network 350 may be composed of a backbone network and a subscriber network. The backbone network may be composed of one or a plurality of integrated networks among an X.25 network, a Frame Relay network, an ATM network, a Multi Protocol Label Switching (MPLS) network, and a Generalized Multi Protocol Label Switching (GMPLS) network. Subscriber networks include FTTH (Fiber To The Home), ADSL (Asymmetric Digital Subscriber Line), cable network, zigbee, Bluetooth, and wireless LAN (IEEE 802.11b, IEEE 802.11a, IEEE 802.11g, IEEE 802.11n ), Wireless Hart (ISO/IEC62591-1), ISA100.11a (ISO/IEC 62734), CoAP (Constrained Application Protocol), MQTT (Message Queuing Telemetry Transport), WIBro (Wireless Broadband), Wimax, 3G, HSDPA (High Speed Downlink Packet Access), 4G and 5G. In some embodiments, the communication network 350 may be an internet network or a mobile communication network. In addition, the communication network 350 may include all other well-known wireless communication or wired communication methods to be developed in the future.

2 is a block diagram for explaining a flow rate calculation device according to an embodiment of the present invention, and FIGS. 3 to 6 are perspective views for explaining how an RF transceiver and a sensor unit are installed in a pipe according to an embodiment of the present invention. 7 is a view for explaining a process of measuring the water level of a fluid using an ultrasonic sensor by a sensor unit according to an embodiment of the present invention, and FIG. 8 is a full water level by a sensor unit according to an embodiment of the present invention using an ultrasonic sensor. 9 is a view for explaining a process of measuring the flow rate at the obesity level using a radar sensor by the sensor unit according to an embodiment of the present invention, FIGS. 10 and 11 is a diagram for explaining a process of calculating the height of precipitate at the full water level by the flow rate calculation device according to an embodiment of the present invention using an RF transceiver, and FIGS. 12 and 13 are flow rate calculation devices according to an embodiment of the present invention It is a diagram for explaining the process of calculating the height of the precipitate at the rain level using the RF transceiver.

Here, Figure 3 is a view of the RF transceiver and the sensor unit installed in the pipe viewed from one side, Figure 4 is a view showing the RF transceiver and the sensor unit installed in the pipe viewed from the other side, Figure 5 is the RF transceiver and It is a view of the sensor unit installed in the pipe viewed from the top, and FIG. 6 is a view of the RF transceiver and the sensor unit installed in the pipe viewed from the bottom.

1 to 13, the flow rate calculation device 100 includes an RF transceiver 10, a sensor unit 20, and a control unit 30, and further includes an interface unit 40 and a storage unit 50. can include

The RF transceiver 10 transmits and receives RF signals. To this end, the RF transceiver 10 includes an RF transmitter 11 and a plurality of RF receivers 13 .

The RF transmitter 11 is installed on top of the pipe 400. Preferably, the RF transmitter 11 may be installed at the top of the pipe 400. The RF transmitter 11 transmits an RF signal toward the inside of the pipe 400. Here, the RF transmitter 11 may transmit an RF signal having a constant frequency.

A plurality of RF receivers 13 are installed in the lower part of the pipe 400, and each of the RF receivers 13a, 13b, 13c, and 13d are installed at different distances from the RF transmitter 11 along the circumferential surface. That is, each of the RF receivers 13a, 13b, 13c, and 13d are installed at different heights. For example, the plurality of RF receivers 13 may include n RF receivers, and each RF receiver 13a, 13b, 13c, 13d is spaced apart from the RF transmitter 11 in a zigzag order. installed That is, in the plurality of RF receivers 13, the first RF receiver 13a, which is the highest RF receiver, is placed on the left side of the center of the pipe 400, and the second RF receiver, which is the next highest RF receiver, is placed. The RF receiver 13b is disposed on the right side with respect to the center of the pipe 400, and the third RF receiver 13c, which is an RF receiver disposed at a higher position next to the pipe 400, may be disposed on the left side with respect to the center of the pipe 400. . In addition, among the plurality of RF receivers 13, the n-th receiver 13d, which is an RF receiver disposed at the lowest position, may be disposed at the lowermost central position. Preferably, each of the plurality of RF receivers 13 may be installed at a position where a path loss value, which is a loss value according to a transmission distance of an RF signal, increases by a predetermined ratio based on when the fluid is full. .

The sensor unit 20 transmits an ultrasonic signal or a radar signal to the inside of the pipe 400 to measure the level and velocity of the fluid A flowing inside the pipe 400 . The fluid A means a liquid, and may include, for example, tap water, rainwater, sewage, and the like. The sensor unit 20 includes a plurality of ultrasonic sensors 21 and a radar sensor 23 .

The plurality of ultrasonic sensors 21 include a first ultrasonic sensor 21a for measuring the level of the fluid A, a second ultrasonic sensor 21b for measuring the flow rate of the fluid A, and a third ultrasonic sensor 21c. include The first ultrasonic sensor 21a is installed at the top of the pipe 400, transmits an ultrasonic signal in the direction of the surface of the fluid A, passes through the air space B of the pipe 400, and returns the ultrasonic wave. The signal is received to measure the level of the fluid (A). The second ultrasonic sensor 21b and the third ultrasonic sensor 21c are installed at the top of the pipe 400 and measure the flow rate of the fluid A using the transmission time difference value of the ultrasonic signal according to the flow rate measurement principle. That is, the second ultrasonic sensor 21b and the third ultrasonic sensor 21c may transmit ultrasonic signals in the direction of the precipitate C and receive the returned ultrasonic signals to measure the flow rate of the fluid A. The second ultrasonic sensor 21b and the third ultrasonic sensor 21c may measure the flow rate when the water level of the fluid A is full.

The radar sensor 23 is installed at the top of the pipe 400 and measures the flow rate of the fluid A based on the Doppler effect. That is, the radar sensor 23 transmits a radar signal in the direction of the surface of the fluid A, passes through the air space B of the pipe 400, and uses the value provided by the returned Doppler radar signal to transmit the fluid ( The flow rate of A) can be measured. The radar sensor 23 may measure the flow velocity when the water level of the fluid A is the obesity level.

The controller 30 performs overall control of the flow rate calculating device 100 . The control unit 30 includes a sediment height calculating unit 31 and a flow rate calculating unit 33 .

The precipitate height calculator 31 calculates the height of the precipitate C deposited in the pipe using the RF signal. The precipitate height calculation unit 31 may calculate the height of the precipitate (C) in a customized manner suitable for the water level state of the fluid (A). Here, when the precipitate height calculation unit 31 transmits the RF signal into the pipe 400, it uses the path loss value of the signal that varies through different media (fluid (A), air space (B) and sediment (C)) The height of the precipitate (C) can be calculated. That is, in the precipitate height calculation unit 31, the received signal strength of the RF receiver fluctuates greatly due to the multipath signal in the air, but the multipath signal is rapidly attenuated in the fluid, so that the received signal strength value of the RF receiver is very high for the distance. The property of having a stable constant value can be used. In addition, the precipitate height calculation unit 31 may use a characteristic that a path loss value is smaller when the multi-path signal passes through the fluid and the precipitate than when the multi-path signal passes through the fluid only.

According to one embodiment, the RF transmitter 11 is installed at the top of the pipe 400, and a plurality of RF receivers 13, a first RF receiver (Rx_1) (13a) and a second RF receiver (Rx_2) (13b) ), under the condition that the third RF receiver (Rx_3) 13c to the nth RF receiver (Rx_n) 13d are installed at different heights along the circumferential surface, the precipitate height calculator 31 flows the fluid into the pipe 400 If (A) is full water level, the height of sediment (C) can be calculated in the following way.

The precipitate height calculator 31 transmits an RF signal into the pipe 400 through the RF transmitter 11 . At this time, the precipitate height calculation unit 31 controls only the RF receiver receiving the RF signal to be in an on state so that radio interference between the plurality of RF receivers 13 does not occur, and the remaining RF receivers are turned off. Control. The precipitate height calculator 31 calculates a path loss value using received signal strength values of RF signals received from a plurality of RF receivers 13 . The precipitate height calculation unit 31 may generate a graph by connecting the calculated path loss value, and calculate the height of the precipitate (C) using the generated graph.

The sediment height calculation unit 31 may calculate the path loss value using [Equation 1].

The transmitted signal strength is the signal strength transmitted from the RF transmitter 11, and may be transmitted at a constant strength, and the received signal strength refers to the signal strength received by each RF receiver 13.

At this time, when the precipitate C does not exist (FIG. 10(a)), the path loss value for each RF receiver can be expressed as [Equation 2], and the graph connecting the path loss values is shown in FIG. It can be shown as (b).

Rx_i means the path loss value (dB) from the RF transmitter to the i-th located RF receiver, La means the path loss value (dB) from the RF transmitter to the first RF receiver (Rx_1), and ΔL is the unit It means the path loss value (dB).

That is, the precipitate height calculation unit 31 determines that the precipitate C does not exist by determining that there is no change in the medium when the graph connecting the calculated path loss values includes an X straight line having one constant slope value.

In addition, when precipitate (C) exists (FIG. 11(a)), the path loss value for each RF receiver can be expressed as [Equation 3], and the graph connecting the path loss values is shown in FIG. It can be shown as b).

Rx_i means the path loss value (dB) from the RF transmitter to the i-th located RF receiver, La means the path loss value (dB) from the RF transmitter to the first RF receiver (Rx_1), and ΔL is the unit It means the path loss value (dB), and a means the path loss correction value for sediment.

That is, the precipitate height calculation unit 31 determines that if the graph connecting the calculated path loss values includes an X line having a constant slope value and a Y line having a slope value smaller than the slope value of the X line, the medium is deposited in the fluid. It can be determined that the precipitate (C) exists by determining that it has been changed to . The precipitate height calculation unit 31 may determine that the precipitate (C) exists from the point where the X straight line and the Y straight line intersect, and calculate the height of the precipitate (C) using the determined result.

According to another embodiment, the RF transmitter 11 is installed at the top of the pipe 400, and the plurality of RF receivers 13 are a first RF receiver (Rx_1) (13a) and a second RF receiver (Rx_2) (13b). ), under the condition that the third RF receiver (Rx_3) 13c to the nth RF receiver (Rx_n) 13d are installed at different heights along the circumferential surface, the precipitate height calculator 31 only partially extends the pipe 400 When the fluid (A) is in a cold state, the height of the precipitate (C) can be calculated in the following way.

The precipitate height calculator 31 transmits an RF signal into the pipe 400 through the RF transmitter 11 . At this time, the precipitate height calculation unit 31 controls only the RF receiver receiving the RF signal to be in an on state, and controls the remaining RF receivers to be in an off state so that radio interference between the plurality of RF receivers 13 does not occur. The precipitate height calculator 31 calculates a path loss value using received signal strength values of RF signals received from a plurality of RF receivers 13 . The precipitate height calculation unit 31 may generate a graph by connecting the average values of the calculated path loss values, and calculate the height of the precipitate (C) using the generated graph.

At this time, when the water level of the fluid A is higher than the height at which the plurality of RF receivers 13 are installed without precipitate C being present (Fig. 12(a)), the path loss value for each RF receiver is [mathematics Equation 4], and a graph connecting the average value of path loss values can be shown as shown in FIG. 12(b). In (b) of FIG. 12, different colors represent cases in which the measured times are different. Here, as shown in (b) of FIG. 12, the reason why several path loss values exist even in the same RF receiver may be a phenomenon caused by interference caused by multi-paths generated while passing through the air.

Rx_i means the path loss value (dB) from the RF transmitter to the i-th located RF receiver, Lb means the path loss value (dB) from the RF transmitter to the first RF receiver (Rx_1), and ΔL is the unit It means the path loss value (dB). At this time, since the path loss of water is relatively smaller than the path loss in air, the Lb value is smaller than the La value.

That is, the precipitate height calculation unit 31 determines that there is no change in the medium when the graph connecting the average values of the calculated path loss values includes an X straight line having one constant slope value, and the precipitate C does not exist. can be judged to be

In addition, without precipitate (C) (Fig. 12 (a)), the water level of the fluid (A) is lower than the height at which the first RF receiver 13a is installed and higher than the height at which the second RF receiver 13b is installed. When the water level of the fluid A is high, the path loss value for each RF receiver can be expressed as in [Equation 5], and the graph connecting the average value of the path loss values is as shown in (c) of FIG. can be shown In (c) of FIG. 12, different colors represent cases in which the measured times are different. Here, as shown in (c) of FIG. 12, the reason why several path loss values exist even in the same RF receiver may be a phenomenon caused by interference caused by multipath generated while passing through the air.

Rx_i denotes a path loss value (dB) from the RF transmitter to the ith positioned RF receiver, Lc denotes a path loss value (dB) occurring in the air from the RF transmitter to the first RF receiver, and Ld denotes the RF It means a path loss value (dB) generated in air and fluid from a transmitter to a second RF receiver, and ΔL means a unit path loss value (dB). At this time, the Lc value is relatively small because it exists only in air, and the Ld value is relatively large because it includes air and fluid. Therefore, as shown in FIG. 12(c), the path loss slope between the value in air and the fluid is relatively steeper, and the slope in the fluid shows a stable slope with a smaller slope.

That is, the precipitate height calculation unit 31 determines that if the graph connecting the average values of the calculated path loss values includes an X line having a constant slope value and a Y line having a slope value smaller than the slope value of the X line, the medium It can be determined that the precipitate (C) does not exist by determining that only the fluid has been changed from the air.

In addition, when the water level of the fluid A is higher than the height at which the plurality of RF receivers 13 are installed while the precipitate C exists (FIG. 13 (a)), the path loss value for each RF receiver is [Equation 6 ], and a graph in which the average value of the path loss values is connected can be shown as shown in (b) of FIG. 13. In (b) of FIG. 13, different colors represent cases in which the measured times are different. Here, as shown in (b) of FIG. 13, the reason why several path loss values exist even in the same RF receiver may be a phenomenon caused by interference caused by multi-paths generated while passing through the air.

Rx_i means the path loss value (dB) from the RF transmitter to the i-th located RF receiver, Lb means the path loss value (dB) from the RF transmitter to the first RF receiver, and ΔL is the unit path loss value (dB), and a means the path loss correction value for sediment.

That is, the precipitate height calculation unit 31 determines that if the graph connecting the average values of the calculated path loss values includes an X line having a constant slope value and a Y line having a slope value smaller than the slope value of the X line, the medium It can be determined that the precipitate (C) exists by determining that the fluid has been changed to the precipitate. The precipitate height calculation unit 31 may determine that the precipitate (C) exists from the point where the X straight line and the Y straight line intersect, and calculate the height of the precipitate (C) using the determined result.

In addition, while the precipitate (C) exists (Fig. 13 (a)), the water level of the fluid (A) is lower than the height at which the first RF receiver 13a is installed, and the fluid (A) is lower than the height at which the second RF receiver 13b is installed. When the level of A) is high, the path loss value for each RF receiver can be expressed as in [Equation 7], and a graph connecting the average value of the path loss values is shown as in (c) of FIG. can In (c) of FIG. 13, different colors represent cases in which the measured times are different. Here, the reason why several path loss values exist even in the same RF receiver as shown in (c) of FIG. 13 may be a phenomenon caused by interference caused by multi-paths generated while passing through the air.

Rx_i means the path loss value (dB) from the RF transmitter to the i-th located RF receiver, Lc means the path loss value (dB) occurring in the air from the RF transmitter to the first RF receiver, and Ld is the RF It means the path loss value (dB) generated in air and fluid from the transmitter to the second RF receiver, ΔL means the unit path loss value (dB), and a means the path loss correction value for sediment .

That is, the sediment height calculating unit 31 calculates that the graph connecting the average values of the calculated path loss values is an X line having a constant slope value, a Y line having a slope value smaller than the slope value of the X line, and a Y straight line. If a Z straight line having a slope value smaller than the slope value is included, it can be determined that the medium is changed from air to fluid and then from fluid to sediment, and thus, it can be determined that the precipitate (C) exists. The precipitate height calculation unit 31 determines that the fluid (A) flows from the point where the X straight line and the Y straight line intersect, and the precipitate (C) exists from the point where the Y straight line and the Z straight line intersect, and uses the determined result. Thus, the height of the precipitate can be calculated.

The flow rate calculation unit 33 calculates the flow rate of the fluid A flowing in the pipe 400 using the calculated precipitate height and the flow rate of the fluid A. The flow rate calculation unit 33 may calculate the flow rate using [Equation 8].

In detail, the flow rate calculation unit 33 calculates the volume of the precipitate (C) using the height of the precipitate (C) when the fluid (A) is full water level, and calculates the volume of the precipitate (C) in the pipe (400). ) Calculate the volume reflected in the volume of At this time, the flow rate calculator 33 controls the ultrasonic sensor 21 to measure the flow rate of the fluid A through the ultrasonic signal. The flow rate calculation unit 33 may calculate the flow rate using the calculated volume and the measured flow rate. The flow rate calculation unit 33 calculates the volume of the precipitate (C) using the height of the precipitate (C) when the fluid (A) is at the non-water level, and calculates the volume of the precipitate (C) of the pipe 400. Calculate the volume reflected in the volume. At this time, the flow rate calculator 33 controls the radar sensor 23 to measure the flow rate of the fluid A through the radar signal. The flow rate calculation unit 33 may calculate the flow rate using the calculated volume and the measured flow rate.

The flow rate calculation unit 33 may generate monitoring information including information on the calculated flow rate and transmit the generated monitoring information to the user terminal 200 . The monitoring information may include the height of the precipitate, the volume of the precipitate, the flow rate of the fluid, and the flow rate of the fluid.

The interface unit 40 performs communication with the user terminal 200 . The interface unit 40 transmits monitoring information to the user terminal 200 . The interface unit 40 may transmit the corresponding information at predetermined intervals or transmit the corresponding information in real time.

The storage unit 50 stores a program or algorithm for driving the flow rate calculating device 100 . The storage unit 50 stores location information of the plurality of RF receivers 13 and the volume of the pipe 400 . The storage unit 50 stores the height of the precipitate (C), the water level, flow rate and flow rate of the fluid (A). The storage unit 50 stores monitoring information. The storage unit 50 may be a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (eg SD or XD memory, etc.), RAM (Random Access Memory, RAM), SRAM (Static Random Access Memory), ROM (Read-Only Memory, ROM), EEPROM (Electrically Erasable Programmable Read-Only Memory), PROM (Programmable Read-Only Memory), magnetic memory, It may include at least one storage medium of a magnetic disk and an optical disk.

14 is a flowchart for explaining a flow rate calculation method according to an embodiment of the present invention.

Referring to FIGS. 1 and 14, the flow rate calculation method uses an RF signal to determine the presence or absence of precipitates deposited inside the pipe, and if there are precipitates, by calculating the height of the precipitates, a number of expensive ultrasonic sensors are installed. This can save installation cost. The flow rate calculation method uses an ultrasonic signal or a radar signal to calculate the flow rate of the fluid flowing in the pipe in which the volume of the precipitate is reflected, so that the user can check the accurate flow rate.

In step S100, the flow rate calculating device 100 calculates the height of the sediment in the pipe 400. The flow rate calculating device 100 may calculate the height of the precipitate using the RF signal. At this time, the flow rate calculating device 100 may calculate the height of the precipitate using the path loss value of the signal received for each of the plurality of RF receivers.

In step S200, the flow rate calculating device 100 calculates the flow rate of the fluid. The flow rate calculating device 100 calculates the volume of the precipitate using the calculated height of the precipitate, and calculates the volume of the space through which the actual fluid flows by reflecting the calculated volume of the precipitate to the volume of the pipe. The flow rate calculating device 100 calculates the flow rate using the calculated volume of the space and the flow velocity of the fluid. The flow rate calculating device 100 generates monitoring information including information on the calculated flow rate and transmits the generated monitoring information to the user terminal 200 .

15 is a flowchart for explaining step S100 of FIG. 14 in detail.

1 and 15, the flow rate calculation method distinguishes between a full water level in which the pipe is filled with fluid and an empty water level in which only part of the pipe is filled with fluid, and the height of the sediment in a manner suitable for each situation. yields

In step S101, the flow rate calculating device 100 measures the level of the fluid. The flow rate calculating device 100 measures the level of fluid currently flowing in a pipe using an ultrasonic sensor.

In step S103, the flow rate calculating device 100 determines whether the water level is full by using the measured result. The flow rate calculating device 100 performs step S105 when the fluid level is full, and performs step S113 when the fluid level is empty.

In step S105, the flow rate calculating device 100 measures the strength of the received signal for each of the plurality of RF receivers. The flow rate calculating device 100 receives a received signal for each RF receiver installed at different heights and measures the strength of each received signal.

In step S107, the flow rate calculating device 100 calculates a path loss value for each receiver. The flow rate calculating device 100 may calculate the path loss value using [Equation 1] described above.

In step S109, the flow rate calculating device 100 calculates the slope of the path loss value between adjacent points. The flow rate calculating device 100 arranges the path loss values in the order of the height at which the RF receiver is installed, and calculates the slope of a straight line connecting the aligned path loss values.

In step S111, the flow rate calculating device 100 calculates the height of the precipitate. The flow rate calculating device 100 calculates the height of the precipitate using the calculated slope. For example, the flow rate calculating device 100 determines that a phenomenon in which the slope is changed is a phenomenon in which the medium is changed, identifies a point at which the slope is lowered, and calculates the height of the precipitate using the corresponding point.

In step S113, the flow rate calculating device 100 measures the strength of the received signal for each of the plurality of RF receivers. The flow rate calculating device 100 receives a received signal for each RF receiver installed at different heights and measures the strength of each received signal.

In step S115, the flow rate calculating device 100 calculates the path loss value for each receiver m times. The flow rate calculating device 100 may repeatedly calculate the path loss value m times using [Equation 1] described above. That is, the flow rate calculating device 100 calculates the path loss value while minimizing the effect of multi-path interference that may occur while the RF signal passes through the air by repeating the calculation of the path loss value m times.

In step S117, the flow rate calculating device 100 calculates the slope of each group of path loss values. The flow rate calculating device 100 arranges the path loss values in the order of the height of the RF receiver, and groups adjacent path loss values among the aligned path loss values. The flow rate calculating device 100 calculates the slope of a straight line connecting the average values of the grouped path loss values.

In step S119, the flow rate calculating device 100 calculates the height of the precipitate. The flow rate calculating device 100 calculates the height of the precipitate using the calculated slope. For example, the flow rate calculating device 100 determines that a phenomenon in which the slope is changed is a phenomenon in which the medium is changed, identifies a point at which the slope is lowered, and calculates the height of the precipitate using the corresponding point.

16 is a flowchart for explaining step S200 of FIG. 14 in detail.

Referring to FIGS. 1 and 16, the flow rate calculation method distinguishes between a full water level in which the pipe is filled with fluid and an empty water level in which only a part of the pipe is filled with fluid, and the flow rate of the fluid in a manner suitable for each situation. yields

In step S201, the flow rate calculating device 100 determines whether the water level is full. The flow rate calculating device 100 performs step S203 when the fluid level is full, and performs step S207 when the fluid level is empty.

In step S203, the flow rate calculating device 100 measures the flow rate of the fluid using a plurality of ultrasonic sensors. The flow rate calculating device 100 transmits an ultrasonic signal in the direction of the sediment and measures the flow rate of the fluid through a time difference in receiving the returned ultrasonic signal.

In step S205, the flow rate calculating device 100 calculates the flow rate of the fluid. The flow rate calculating device 100 calculates the volume of the precipitate using the height of the precipitate, and calculates a volume obtained by reflecting the calculated volume of the precipitate to the volume of the pipe. The flow rate calculating device 100 calculates the flow rate by using the pipe volume and flow velocity in which the volume of the precipitate is reflected. That is, the flow rate calculating device 100 may calculate the flow rate using [Equation 8] described above.

In step S207, the flow rate calculating device 100 measures the flow rate of the fluid using the radar sensor. The flow rate calculating device 100 transmits a radar signal in the direction of the sediment and measures the flow rate of the fluid using a value provided by the returned Doppler radar signal.

In step S209, the flow rate calculating device 100 calculates the flow rate of the fluid. The flow rate calculating device 100 calculates the volume of the precipitate using the height of the precipitate, and calculates a volume obtained by reflecting the calculated volume of the precipitate to the volume of the pipe. The flow rate calculating device 100 calculates the flow rate by using the pipe volume and flow velocity in which the volume of the precipitate is reflected. That is, the flow rate calculating device 100 may calculate the flow rate using [Equation 8] described above.

17 is a block diagram illustrating a computing device according to an embodiment of the present invention.

Referring to FIG. 17 , the computing device TN100 may be a device described in this specification (eg, a flow rate calculating device, a user terminal, etc.).

The computing device TN100 may include at least one processor TN110, a transceiver TN120, and a memory TN130. In addition, the computing device TN100 may further include a storage device TN140, an input interface device TN150, and an output interface device TN160. Elements included in the computing device TN100 may communicate with each other by being connected by a bus TN170.

The processor TN110 may execute program commands stored in at least one of the memory TN130 and the storage device TN140. The processor TN110 may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. Processor TN110 may be configured to implement procedures, functions, methods, and the like described in relation to embodiments of the present invention. The processor TN110 may control each component of the computing device TN100.

Each of the memory TN130 and the storage device TN140 may store various information related to the operation of the processor TN110. Each of the memory TN130 and the storage device TN140 may include at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory TN130 may include at least one of read only memory (ROM) and random access memory (RAM).

The transmitting/receiving device TN120 may transmit or receive a wired signal or a wireless signal. The transmitting/receiving device TN120 may perform communication by being connected to a network.

Meanwhile, the embodiments of the present invention are not implemented only through the devices and/or methods described so far, and may be implemented through a program that realizes functions corresponding to the configuration of the embodiments of the present invention or a recording medium in which the program is recorded. And, such implementation can be easily implemented by those skilled in the art from the description of the above-described embodiment.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also provided. belong to the scope of the invention.

10: RF transceiver
11: RF transmitter
13: RF receiver
20: sensor unit
21: ultrasonic sensor
23: radar sensor
30: control unit
31: sediment height calculation unit
33: flow calculation unit
40: interface unit
50: storage unit
100: flow calculation device
200: user terminal
300: flow calculation system
350: communication network
400: pipe

Claims (17)

RF transceivers for transmitting radio frequency (RF) signals to the inside of the pipe and receiving the RF signals at different heights;
a sensor unit configured to transmit an ultrasonic signal or a radar signal to the inside of the pipe to measure the level and velocity of the fluid flowing inside the pipe; and
A controller for calculating the height of the precipitate deposited in the pipe using the RF signal and calculating the flow rate of the fluid flowing in the pipe using the height of the precipitate and the flow rate,
The RF transceiver unit,
an RF transmitter installed at the top of the pipe and transmitting an RF signal toward the inside of the pipe; and
A plurality of RF receivers installed at different distances from the RF transmitter along the circumferential surface of the pipe and individually receiving the RF signal;
Each of the plurality of RF receivers,
The flow rate calculation device, characterized in that installed so that the distance from the RF transmitter in a zigzag order based on the pipe center. delete According to claim 1,
Each of the plurality of RF receivers,
The flow rate calculation device characterized in that installed at a position where a path loss value, which is a loss value according to the transmission distance of the RF signal, is increased by a predetermined ratio based on when the fluid is at a full water level. delete According to claim 1,
The control unit,
Flow rate calculation device, characterized in that for controlling only the RF receiver receiving the RF signal to an on state, and controlling the remaining RF receivers to an off state so that signal interference between the plurality of RF receivers does not occur. According to claim 1,
The control unit,
If the pipe is full of the fluid,
Calculating path loss values for the plurality of RF receivers, respectively, and determining that the precipitate does not exist when a graph connecting the calculated path loss values includes a straight line having one constant slope value. Characterized in that flow calculation device. According to claim 1,
The control unit,
If the pipe is full of the fluid,
Each path loss value for the plurality of RF receivers is calculated, and a graph connecting the calculated path loss values has a first straight line having a constant slope value and a slope value smaller than the slope value of the first straight line. The flow rate calculation device, characterized in that it is determined that the precipitate is present when the second straight line is included. According to claim 7,
The control unit,
The flow rate calculation device, characterized in that for determining that the precipitate exists from a point where the first straight line and the second straight line intersect, and calculating the height of the precipitate using the determined result. According to claim 1,
The control unit,
If only a part of the pipe is filled with the fluid, and the fluid level is higher than the height at which the plurality of RF receivers are installed,
Calculating path loss values for the plurality of RF receivers, respectively, and determining that the precipitate does not exist when a graph connecting the average values of the calculated path loss values includes a straight line having one constant slope value Flow calculation device characterized in that. According to claim 1,
The control unit,
When only a portion of the pipe is filled with the fluid and the fluid level is lower than the height at which at least one RF receiver among the plurality of RF receivers is installed,
Each path loss value for the plurality of RF receivers is calculated, and a graph obtained by connecting the average values of the calculated path loss values is a third straight line having a constant slope value and a slope value smaller than the slope value of the third straight line. Flow rate calculation device characterized in that it is determined that the precipitate does not exist when a fourth straight line having is included. According to claim 1,
The control unit,
If only a part of the pipe is filled with the fluid, and the fluid level is higher than the height at which the plurality of RF receivers are installed,
Each path loss value for the plurality of RF receivers is calculated, and a graph obtained by connecting the average values of the calculated path loss values is a fifth straight line having a constant slope value and a slope value smaller than the slope value of the fifth straight line. Flow rate calculation device characterized in that it is determined that the precipitate is present when a sixth straight line having is included. According to claim 11,
The control unit,
The flow rate calculation device, characterized in that for determining that the precipitate exists from a point where the fifth straight line and the sixth straight line intersect, and calculating the height of the precipitate using the determined result. According to claim 1,
The control unit,
When only a portion of the pipe is filled with the fluid and the fluid level is lower than the height at which at least one RF receiver among the plurality of RF receivers is installed,
Each path loss value for the plurality of RF receivers is calculated, and a graph obtained by connecting average values of the calculated path loss values is a seventh straight line having a constant slope value, and a slope value smaller than the slope value of the seventh straight line. The flow rate calculation device, characterized in that it is determined that the precipitate exists when an eighth straight line having a slope value and a ninth straight line having a slope value smaller than the slope value of the eighth straight line are included. According to claim 13,
The control unit,
It is determined that the fluid flows from the point where the seventh straight line and the eighth straight line intersect, and the precipitate exists from the point where the eighth straight line and the ninth straight line intersect. Flow rate calculating device, characterized in that for calculating the height of. According to claim 1,
The control unit,
If the pipe is full of the fluid,
The volume of the precipitate is calculated using the height of the precipitate, the volume of the calculated precipitate reflected in the volume of the pipe is calculated, and the flow rate measured using the calculated volume and the ultrasonic signal is calculated The flow rate calculation device characterized in that for calculating the flow rate. According to claim 1,
If only a portion of the pipe is filled with the fluid, the non-water level,
The volume of the precipitate is calculated using the height of the precipitate, the volume obtained by reflecting the calculated volume of the precipitate to the volume of the pipe is calculated, and the flow rate measured using the calculated volume and the radar signal is used The flow rate calculation device characterized in that for calculating the flow rate. delete

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