KR101076774B1 - Submergence sensing device and method for submergence sensing using the same - Google Patents

Abstract

The present invention is to provide a reliable and corrosion-resistant immersion detection device and a immersion detection method using the same by applying electromotive force between two metal electrodes with different ionization tendency by applying the voltaic battery principle, the immersion of the present invention The sensing device includes a sensor unit including first and second electrodes spaced apart from each other and having different ionization tendencies in the product apparatus; A comparator comprising a reference threshold voltage Vth setting unit and a low power operational amplifier for receiving and outputting a voltage difference between the first and second electrodes; And a control unit configured to receive the output of the comparison unit as an interrupt terminal (Int) or an input / output terminal (GPIO) to control the immersion detection. The present invention described above is resistant to corrosion and contamination of the sensor unit using a voltaic battery principle. In addition, it is possible to implement an inexpensive and stable immersion detection device, and it is possible to miniaturize because it can detect the immersion and level of water except pure water (distilled water) only by using the sensor unit, the comparison unit, and the controller using the voltaic battery principle.

Description

Submersion detection device and submersion detection method using the same {SUBMERGENCE SENSING DEVICE AND METHOD FOR SUBMERGENCE SENSING USING THE SAME}

The present invention relates to an inundation and water level detection device, and in particular, the corrosion caused by long-term immersion in a variety of devices, including a metering system installed and operated in the outdoor, outdoor and specific site inundation area and the place where the inundation occurs due to rainy rainfall The present invention relates to an immersion detection device capable of detecting immersion without contamination and a immersion detection method using the same.

In general, electric power facilities in urban areas are gradually becoming underground due to urban aesthetics, safety, and high-rise buildings, and their weight is increasing day by day.

However, research and development is underway in the joint districts where underground lines are installed along with other facilities, but manholes, etc., still have to rely on manpower. Because it does not.

Therefore, the manhole has a feature that can not be immediately confirmed even in case of emergency, such as intrusion or accident of outsiders. In order to overcome this difficulty and easily manage the manhole at a remote location, a sensor is installed to obtain the necessary information inside the manhole, and a remote alarm system of the manhole is provided so that the information detected by the sensor can be delivered to a point of interest. It is essential to develop a system that can easily check the current detection information of the manhole.

In addition, a conventional water meter is used to mechanically measure the flow of water and convert it to a meter scale. The mechanical meter has to be individually read by a meter reader. Electronic meters with means to enable this have been developed.

In the case of an electronic water meter, the problem of excessive manpower operation due to individual meter reading can be solved. However, since the metering manpower is not directly read, the water meter can lose the advantage of regularly checking the situation of the water meter. For this reason, there has been a continuous demand for a system or method for allowing a manager to grasp not only the meter reading of the remote water meter but also the surrounding situation. In the case of an electronic water meter, a plan for remote managers to recognize the situation of flooding in real time was required, because there is a risk of damage to the device and electric shock due to leakage when the electronic water meter is flooded.

As described above, since corrosion and contamination problems may occur due to prolonged immersion of a device for wirelessly reading a manhole and a water meter, development of a device capable of detecting immersion is required.

Accordingly, in the related art, the following two methods have been proposed as devices capable of sensing inundation.

First, as shown in FIG. 1, the conventional first method receives the state of the first and second electrodes 11 and 12 and the first electrode 11 spaced apart from each other in the product appliance. It consists of the MCU (13) for detecting the. Reference numeral '10' is a drawing of water (electrolyte solution) for easy understanding of the immersion state and is not an essential component.

The first electrode 11 is connected to an input / output terminal (GPIO) or an interrupt (Int) terminal of the MCU 13, a pull-up resistor is disposed between the first electrode 11 and the power supply terminal (VCC), The second electrode 12 is grounded.

The immersion detection apparatus according to the first method of the related art is a technology using a current supply or resistance change between two electrodes of the same type, that is, the first and second electrodes 11 and 12. The immersion furnace first and second electrodes 11, When 12) is submerged in water, the resistance value between the electrodes is lowered, so that the general purpose input output (GPIO) of the control unit, that is, MCU 13, becomes "low" to detect whether or not it is flooded.

More specifically, when no immersion is made, the first electrode 11 is pulled up through the resistor and the second electrode 12 is grounded, so that the first and second electrodes 11 and 12 have a VCC potential difference. Have

On the other hand, when submerged, electric current flows through the first and second electrodes 11 and 12, so that electrolysis occurs at the first and second electrodes 11 and 12, and thus, the first and second electrodes. Severe corrosion occurs at (11, 12), and a "low" signal is detected at the GPIO (General Purpose Input Output) of the MCU 13.

When the immersion detection device according to the first method is applied to a device that requires perfect waterproof for a long time as described above, water penetrates into the device due to electrode corrosion, causing an error in the device, and causing damage to the device. Will be raised.

Next, the water immersion detection apparatus according to the second method is composed of a humidity sensor 21 disposed in the product appliance, and the MCU 22 for controlling the humidity sensor 21, as shown in FIG. do. The humidity sensor 21 has a first end connected to the input terminal of the MCU 22, and the second end is grounded. Reference numeral '20' is a drawing of water (electrolyte solution) for easy understanding of the immersion state and is not an essential component.

The conventional second method is to detect the inundation by using the humidity sensor 21, such a method, there is a risk of detection error due to the high humidity in the air during the summer rainy season, the external dependence because the commercial humidity sensor is applied There is a problem that the increase in the design and manufacturing of the mechanism, which leads to a rise in manufacturing cost and a large development cost.

The present invention has been proposed to solve the above problems according to the prior art, by applying the electromotive force between two metal electrodes having different ionization tendency by applying the voltaic battery principle, the immersion detection device having high reliability and corrosion resistance when immersion detection; The purpose is to provide a method for detecting flooding using the same.

Immersion detection apparatus of the present invention for achieving the above object is a sensor unit consisting of first and second electrodes spaced apart from each other and having a different ionization tendency in the product appliance; A comparator comprising a reference threshold voltage Vth setting unit and a low power operational amplifier for receiving and outputting a voltage difference between the first and second electrodes; And a controller configured to control the flooding detection by receiving the output of the comparison unit as an interrupt terminal Int or an input / output terminal GPIO.

In this case, among the first and second electrodes, a metal having a high ionization tendency is used as a (-) electrode and a small metal as a (+) electrode, and the first and second electrodes are K, Ca, Na, Mg, Al And Zn, Fe, Ni, Sn, Pb, Cu, Hg, Ag, Pt and Au, respectively, and are composed of metals having different ionization tendencies.

The first input terminal IN + of the low power operational amplifier is connected to the first electrode, and the second input terminal IN− is connected to the reference threshold voltage Vth setting unit.

The reference threshold voltage Vth setting unit is configured by connecting a first resistor, a variable resistor, and a second resistor in series between the power supply voltage terminal VCC and the ground voltage terminal VSS. It is characterized in that the two electrodes are connected.

In addition, the immersion detection method using the immersion detection device of the present invention, the step of initializing the immersion detection device; Determining whether to detect by an interrupt method or a polling method in order to determine whether the water is flooded and an efficient detection method; If it is determined that the interrupt method is the interrupt method, registering, enabling, and returning a flood detection interrupt interrupt service routine (ISR); And if it is determined that the polling method is the polling method, after setting a polling enable and polling period and an average number, the sensor unit of the immersion sensing device is read and an average accumulation is performed. After determining whether the number, the average of the cumulative sensor sampling value, and whether the immersion has occurred, if it is determined that the immersion occurs, it is characterized by repeating the operation of sequentially informing the detection of the immersion detection and the lead again.

In this case, the immersion detection interrupt ISR reads the immersion detection signal of the sensor unit for immersion detection and sampling the output value of the comparator by the number of moving averages; Calculating an average of the sampled values of the moving average number; Determining whether an immersion is detected; If it is determined that the immersion has occurred, returning to the interrupt method after notifying that the immersion has been detected; And if it is determined that the immersion has not occurred, the method returns to the interrupt method.

In addition, the polling method determines whether the immersion detection signal of the led sensor unit is an average cumulative number, and if it is determined that the average cumulative number is not the average cumulative number, the sensor unit re-enters the sensor unit of the immersion sensing apparatus.

If it is determined that the immersion has occurred and it is determined that the immersion has not occurred, the process re-enters the operation to lead the sensor unit of the immersion sensing apparatus.

The present invention described above has the effect of being resistant to corrosion and contamination of the sensor unit using a voltaic battery principle, and implementing an inexpensive and stable immersion sensing device.

In addition, since the sensor unit, the comparison unit, and the control unit using the voltaic battery principle can detect water ingress and water level except pure water (distilled water), miniaturization is possible.

1 is a block diagram showing an inundation detection apparatus according to the first method.
2 is a block diagram showing an inundation detection apparatus according to a second method.
3 is a block diagram showing an inundation detection apparatus according to an embodiment of the present invention.
4 is a conceptual diagram in which a plurality of metals are arranged according to the magnitude of the ionization tendency.
5 is a flowchart illustrating a flooding detection method according to an embodiment of the present invention.

The present invention can be applied to the detection of the flooding state of the wireless metering terminal installed in the manhole and water meter protection tube in the wireless remote meter reading system, the flooding detection of the device installed in the flooded or flooded area outdoors, the river or river water level detection The present invention relates to a submerged sensing device and a submerged sensing method using the same.

Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. .

As shown in FIG. 3, the immersion detection apparatus according to the present invention includes a sensor unit 30, a comparison unit 40, and a control unit 50.

The sensor unit 30 includes first and second electrodes 32 and 33 spaced apart from each other and having different ionization tendencies in the product appliance. Reference numeral '31' represents water (electrolyte solution), which is only a drawing for easy understanding of the immersion state in the installation environment, and is not an essential component of the present invention.

In this case, the first and second electrodes 32 and 33 are made of metals having different ionization tendencies, and the metal having a high ionization tendency is used as the negative electrode and the small metal is used as the positive electrode. The electromotive force (potential difference) between the first and second electrodes 32 and 33 is generated differently.

The metals used as the first and second electrodes 32 and 33 are formed of metals having different ionization tendencies.

Among the metals that can be used for the first and second electrodes 32 and 33, metals having a high ionization tendency are sequentially presented, and as shown in FIG. 4, K> Ca> Na> Mg> Al> Zn> Fe> Ni> Sn> Pb> Cu> Hg> Ag, Pt> Au.

For example, when Cu and Sn metals are used, Cu is used as a positive electrode and Sn is used as a negative electrode. In this case, the first electrode 32 uses Cu and the second electrode 33 Sn can be used. When the first and second electrodes 32 and 33 composed of Cu and Sn are immersed in an electrolyte solution (water), an electromotive force is generated about 0.8 to 1.8 [V] between the electrodes.

As described above, the sensor unit 30 including the first and second electrodes 32 and 33 is configured using the principle of the voltaic battery, and the first and second electrodes 32 and 33 are the Sn and Cu described above. In addition to metals, metals with different ionization tendencies may be used.

The comparator 40 includes a low power operational amplifier 41 that receives and outputs a voltage difference between the first and second electrodes 32 and 33, and a reference threshold voltage Vth setting unit 42.

The first input terminal IN + of the low power operational amplifier 41 is connected to the first electrode 32, and the second input terminal IN− is connected to the reference threshold voltage Vth setting unit 42.

The reference threshold voltage Vth setting unit 42 connects a first resistor R1, a variable resistor RV and a second resistor R2 between a power supply voltage terminal VCC and a ground voltage terminal VSS. The second electrode 33 is connected to the ground voltage terminal.

In order to determine whether the immersion is in the above, the reference threshold voltage Vth of the stable comparator 40 should be determined by referring to the generation potential difference between the first and second electrodes 32 and 33. For example, when the potential difference is about 0.8V when the first and second electrodes 32 and 33, which are the sensor electrodes of the sensor unit 30, are immersed in the electrolyte solution, the threshold voltage Vth is set to about 0.5V. Can be detected.

Next, the controller 50 is composed of an MCU 50 that receives the output of the comparator 40 as an interrupt terminal Int or an input / output terminal GPIO and drives the same.

When the immersion detection signal is generated from the sensor electrodes, that is, the first and second electrodes 32 and 33, the controller 50 immediately detects the immersion without error and performs an appropriate function. More specifically, when the immersion detection signal is generated from the comparison unit 40, the processing method of the controller 50 may vary depending on the purpose of operation for the determination of the immersion and efficient detection method, by the interrupt There is a sensing method and a sensing method by polling to determine by polling a comparison output at a predetermined period.

In general, an interrupt means that a CPU (Central Processing Unit) itself checks a state in hardware and responds to a change when an unexpected problem occurs in a running device. When an interrupt occurs, an interrupt handling routine in the control program within the operating system is activated to resolve the emergency and return to the state before the interrupt occurred.

Generally, there are interrupt methods and polling methods, which can be used to execute two or more processors at the same time, and to make it easier to identify abnormalities. to be.

Using the interrupt-based method for the same reason, it is possible to quickly report the status and the corresponding action immediately upon the inundation occurs, it is advantageous to operate at low power.

In the polling method, the controller 50 always reads the output of the comparator at regular intervals and determines whether it is flooded. In such a case, a compromise between two factors, polling cycle and current consumption, is required. If the polling cycle is shortened and the comparison output is frequently read, the flooding can be quickly known. However, the controller 50 consumes a lot of current, and must wait for a polling period.

In order to minimize the error in detecting the flooding, the comparative output is sampled several times to several ten times and averaged. In addition, a ping-pong phenomenon occurs in which the first and second electrodes 32 and 33 move back and forth from the immersion water level threshold, which causes a burden on the MCU 50 or a detection result during the polling process. Shaking may occur. To solve this problem, a conventional Schmitt trigger (hysteresis) technique can be applied.

As described above, the present invention attaches two metal electrodes having different ionization tendencies, namely, first and second electrodes 32 and 33 to the outside of the apparatus of the application device, and connects them to the sensing circuit unit inside the apparatus. The proposed method is to apply the principle of voltaic battery in which electromotive force of a certain voltage is generated when two metal electrodes having different ionization tendency are immersed in the electrolyte solution. When the potential difference of the generated electromotive force is detected, the immersion / water level can be known.

In addition, the method of detecting the generated potential difference uses a method of detecting a submerged state when the reference voltage is higher than the reference voltage by comparing the constant reference voltage with a threshold voltage.

Subsequently, when the immersion detection signal is generated from the comparator 40, the processing method for the immersion detection of the controller 50 is as follows.

First, as shown in Figure 5, prepare an initialization step for the immersion detection function (S51) At this time, to initialize the immersion detection function is to initialize the system so that the immersion detection device is running smoothly.

After preparing the initialization step as described above, it is determined whether the detection by the interrupt (polling) method or the polling (polling) method for determining whether the flooding and efficient detection method (S52).

As a result of the determination, if it is determined that the system is an interrupt system, the flood detection interrupt ISR (Interrupt Service Routine) is registered and enabled (S53).

Thereafter, a return operation is performed (S54).

In interrupt mode, ISRs are numbered for critical and other user-defined situations in the processor. When an interrupt occurs, it interrupts the current task and takes precedence.

If the flow chart of the immersion detection ISR is further described, first, the immersion detection signal of the sensor unit 30 of the immersion detection device is read, and the output value of the comparison unit is sampled by the number of moving averages (S56).

Thereafter, the average of the sampled values of the number of moving averages is calculated (S57).

Next, it is determined whether or not flooding is detected. (S58)

As a result of the determination, if it is determined that the immersion has occurred, it is notified that the immersion has been detected (S59), and the process returns to the step before the interrupt generation (S60).

If it is determined that the immersion has not occurred, the operation immediately returns to the interrupt method. (S60)

If it is determined that the polling method is the polling method or the polling method, the polling enable and polling periods and the average number are set (S61).

Thereafter, the immersion detection signal of the sensor unit 30 of the immersion detection device is read (S62).

Next, it is determined whether or not the number of submerged detection signals of the read sensor unit 30 is an average cumulative number (S63).

If the determination result is an average cumulative number, the average of the cumulative sampling values of the sensor unit 30 is calculated (S64). If the determination result is not the average cumulative number, the determination result is re-entry into the operation of reading the sensor unit 30 of the immersion sensing device. do.

Then, after calculating the average of the cumulative sampling values of the sensor unit 30, it is determined whether or not immersion has occurred. (S65)

Subsequently, if it is determined that immersion has occurred and it is determined that immersion has occurred, an immersion detection notification signal is output. (S66) If it is determined that immersion has not occurred, the sensor unit 30 of the immersion detection apparatus is read. Re-enter

As described above, when the first and second electrodes 32 and 33 of the sensor unit 30 are near the immersion water level threshold, the immersion state may swing back and forth until complete immersion. To filter, we accumulate several times at regular time intervals and average them to obtain stable flood information.

Although the technical idea of the present invention has been described in detail according to the above-described preferred embodiment, the above-described embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention. Accordingly, the scope of the invention should be defined by the claims rather than by the examples described.

* Explanation of symbols for the main parts of the drawings
30: sensor unit 31: water (electrolyte solution)
32: first electrode 33: second electrode
40: comparator 41: low power operational amplifier
42: reference threshold voltage (Vth) setting unit 50: control unit

Claims (9)

A sensor unit comprising first and second electrodes spaced apart from each other and having different ionization tendencies in the product appliance to apply the principle of a voltaic battery;
The first resistor, the variable resistor and the second resistor are connected in series between the power supply voltage terminal VCC and the ground voltage terminal VSS, and the reference threshold voltage Vth to which the second electrode is connected is connected to the ground voltage terminal. A comparison unit including a setting unit and a low power operational amplifier for outputting a submersion detection signal when the voltage difference between the first and second electrodes is equal to or greater than a threshold voltage Vth; And
And a control unit configured to control the flooding detection by receiving the output of the comparing unit as an interrupt terminal (Int) or an input / output terminal (GPIO). The method of claim 1,
In the first and second electrodes, a metal having a high ionization tendency is a negative electrode and a small metal is used as a positive electrode. The method of claim 1,
The first and second electrodes are made of a metal having a different ionization tendency among K, Ca, Na, Mg, Al, Zn, Fe, Ni, Sn, Pb, Cu, Hg, Ag, Pt and Au. Immersion detection device. The method of claim 1,
And a first input terminal (IN +) of the low power operational amplifier is connected to the first electrode, and a second input terminal (IN-) is connected to the reference threshold voltage (Vth) setting unit. delete In the method of detecting the immersion using the immersion detection device according to any one of claims 1 to 4,
Initializing the flood detection function;
Determining whether to detect by an interrupt method or a polling method in order to determine whether the water is flooded and an efficient detection method;
If it is determined that the interrupt method is the interrupt method, registering, enabling, and returning a flood detection interrupt interrupt service routine (ISR); And
If it is determined that the polling method is the polling method, after setting a polling enable and polling period and an average number, the sensor unit of the immersion sensing device is read and an average accumulation number is set. And determining the average of the sensor sampling cumulative values, determining whether or not the inundation occurs, and if it is determined that the inundation has occurred, informing the inundation detection and repeatedly leading the sensor unit. Immersion detection method using. The method of claim 6,
The immersion detection interrupt ISR reads the immersion detection signal of the sensor unit for immersion detection and sampling the output value of the comparator by the number of moving averages;
Calculating an average of the sampled values of the moving average number;
Determining whether an immersion is detected;
If it is determined that the immersion has occurred, returning to the interrupt method after notifying that the immersion has been detected; And
And if it is determined that the immersion has not occurred, the immersion detection method using the immersion detection apparatus, characterized in that to return to the interrupt method. The method of claim 6,
In the polling method, the immersion detection signal of the sensor part is determined as the average cumulative number, and if it is determined that it is not the average cumulative number, the immersion sensing device, characterized in that the re-entry operation to lead the sensor unit of the immersion sensing device. Immersion detection method using. The method of claim 6,
Determining whether the immersion has occurred, and if it is determined that the immersion has not occurred, the immersion detection method using the immersion detection apparatus, characterized in that the re-entry in the operation of leading the sensor unit of the immersion sensing device.

Images