KR101325994B1 - Apparatus and Method for Controlling Electric Conductivity Sensor - Google Patents

Abstract

An apparatus and method for controlling an conductivity sensor is disclosed. Electrical conductivity sensor control device according to an aspect of the present invention, the input terminal for supplying power to the control device, the electrode unit for measuring the electrical conductivity and temperature, the measured electrical conductivity and temperature signal data corresponding to the CAN communication protocol And an output terminal for outputting the converted output circuit, wherein the input terminal and the output terminal have a structure in a state of being electrically insulated from the electrode unit.
Here, the electrode unit AC signal generating unit for generating an AC signal for measuring the conductivity, an electrical conductivity signal output measuring unit for detecting the electrical conductivity by flowing the AC signal to the coolant, a temperature signal measuring unit for detecting the temperature of the cooling water Include.

Description

Apparatus and Method for Controlling Electric Conductivity Sensor

The present invention relates to an electrical conductivity sensor, and more particularly to an apparatus and a control method for controlling the electrical conductivity sensor for measuring the electrical conductivity of the coolant for cooling the fuel cell stack.

In general, the fuel cell vehicle drives the vehicle by converting chemical energy of the fuel into electrical energy, so that heat is generated in the fuel cell stack. Thus, the fuel cell vehicle uses cooling water to cool the fuel cell stack.

However, since the fuel cell stack is deteriorated in durability and performance due to metal ions, the coolant of the fuel cell vehicle should use distilled water having a constant electrical conductivity of which metal ions have been removed. Therefore, the fuel cell vehicle uses a conductivity sensor to measure and manage the electrical conductivity of the cooling water flowing in the cooling water pipe.

Conventional industrial conductivity sensor was configured by connecting the electrode and the transmitter (Transmitter) provided with each wire, and transmitted the electrical conductivity measured through the transmitter to a computer.

As described above, the conventional industrial conductivity sensor is an electrode and a transmitter separated type, which makes the manufacturing process cumbersome, and in terms of structure, leakage occurs easily in the fuel rod portion of the cooling water pipe, thereby causing a breakdown.

SUMMARY OF THE INVENTION The present invention has been made in the technical background as described above, and an object thereof is to provide an electrical conductivity measuring apparatus which can be integrally configured in one housing.

Another object of the present invention is to provide an electrical conductivity measuring device capable of electrically connecting each electrode and the control unit by a spring.

It is still another object of the present invention to provide a control device and a control method of a conductivity sensor for transmitting measured temperature and conductivity signals as digital signals through a CAN interface.

Electrical conductivity sensor control device according to an aspect of the present invention, the input terminal for supplying power to the control device, the electrode unit for measuring the electrical conductivity and temperature, the measured electrical conductivity and temperature signal data corresponding to the CAN communication protocol And an output terminal for outputting the converted output circuit, wherein the input terminal and the output terminal have a structure in a state of being electrically insulated from the electrode unit.

Here, the electrode unit AC signal generating unit for generating an AC signal for measuring the conductivity, an electrical conductivity signal output measuring unit for detecting the electrical conductivity by flowing the AC signal to the coolant, a temperature signal measuring unit for detecting the temperature of the cooling water Include.

The conductivity signal output measurement unit performs calibration on the detected conductivity using a dry correction algorithm.

In addition, the conductivity sensor control apparatus according to the present invention may further include a self-diagnostic unit for detecting the abnormality of the AC signal generator, the conductivity signal output measurement unit and the temperature signal measurement unit.

The self-diagnosis unit transmits a self-diagnosis message to each of the AC signal generator, the electric conductivity signal output measuring unit, and the temperature signal measuring unit, and performs a self-diagnosis by counting the number of reply messages to the transmitted message.

According to the present invention, the electrode, the control unit and the transmission unit are included in one mechanism, and the electrode and the control unit can be electrically connected by a spring, thereby improving the inconvenience and the defective rate of the conventional assembly / manufacturing process that performed the soldering and cable process. Can reduce the size of the product, reduce the cost of implementation.

In addition, the present invention can be connected to the coupling hole to prevent the leakage of the coolant through the coupling hole by adding an O-ring made of a rubber material blocking the gap of the coupling hole.

In addition, the present invention does not need to be equipped with a temperature sensor by applying the temperature of the cooling water together, and transmit electrical conductivity to the vehicle through the vehicle network to be robust to noise, and easily transmit and receive diagnostic information (Diagnosis) can do.

In addition, by transmitting the measured temperature and conductivity as a digital signal through the CAN interface, noise immunity is increased, and a separate circuit configuration for analog current measurement in the ECU is not required, thereby reducing system production costs. It works.

1 is a block diagram showing an electrical conductivity measuring apparatus according to an embodiment of the present invention.
2 is a cross-sectional view of an electrical conductivity measurement apparatus according to an embodiment of the present invention.
3 is a perspective view of an electrical conductivity measuring apparatus according to an embodiment of the present invention.
4 is a mounting example of the conductivity measurement device according to an embodiment of the present invention.
Figure 5 is a block diagram showing a control device of the conductivity sensor according to another embodiment of the present invention.
6 is a flow chart showing a control method of the conductivity sensor according to another embodiment of the present invention.
7 is a view showing an example of a method for extracting a representative characteristic curve of the conductivity sensor in the present invention.
8 is a view showing an example of a trimming process in the present invention.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. As used herein, the terms " comprises, " and / or "comprising" refer to the presence or absence of one or more other components, steps, operations, and / Or additions.

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. 1 is a block diagram showing an electrical conductivity measuring apparatus according to an embodiment of the present invention.

As shown in FIG. 1, the conductivity measuring apparatus 10 according to an exemplary embodiment of the present invention includes first and second electrodes 111 and 112, first and second springs 121 and 122, and first and second electrodes. The second connector 131 and 132, the controller 140, the temperature sensor 150, the transmitter 160, and the connector 170 are included. In this case, the first and second connectors 131 and 132, the controller 140, the temperature sensor 150, the transmitter 160, and the connector 170 may be components mounted on the printed circuit board 180.

The first and second electrode rods 111 and 112 are immersed in the cooling water of the cooling water pipe, and are provided through the control unit 140, the first and second springs 121 and 122, and the first and second connecting portions 131 and 132. Electrically connected.

One end of the first and second springs 121 and 122 is in contact with the other end of the first and second electrode bars 111 and 112 respectively corresponding to one end contained in the cooling water of the first and second electrode bars 111 and 112. The other ends of the first and second springs 121 and 122 contact the first and second connecting portions 131 and 132, respectively.

The first and second springs 121 and 122 may be annular springs made of a conductive material, and contact the other ends of the first and second electrode rods 111 and 112 and the first and second connecting portions 131 and 132, respectively. The interface between the first and second electrode rods 111 and 112 and the controller 140 is electrically connected to each other.

The first and second connectors 131 and 132 may be pads PAD of the printed circuit board 180 and are electrically connected to the first and second electrode interfaces of the controller 140.

The controller 140 supplies an AC voltage to the first and second electrode rods 111 and 112 through the first and second connectors 131 and 132 and the first and second springs 121 and 122, thereby providing resistance of the cooling water. The value R is measured, and the electrical conductivity L of the coolant is measured and transmitted to the transmitter 160 according to Equation 1 below.

Where ρ [Ωm] is the specific resistance (intrinsic resistance), l is the spacing [m] of the first and second electrode bars 111 and 112, and S is the cross-sectional area of the first and second electrode bars 111 and 112 [ M 2].

The transmitter 160 is, for example, a controller area network (CAN) transceiver. The transmitter 160 converts electrical conductivity of the coolant received from the controller 140 into data for a vehicle network and transmits the data to the vehicle network through the connector 170.

The connector 170 is mounted on the printed circuit board 180 to connect the vehicle network to the transmitter 160 via a cable.

The temperature sensor 150 measures the temperature of the coolant and transmits the temperature to the vehicle network through the controller 140 or the transmitter 160. Here, when the electrical conductivity measuring device 10 is configured to measure only the electrical conductivity, the temperature sensor 150 may be omitted.

Meanwhile, when the vehicle receives the electrical conductivity or temperature of the coolant and deviates from the preset reference, the vehicle may perform predetermined control (eg, supply of new coolant).

Hereinafter, the structure of an electrical conductivity measuring apparatus according to an exemplary embodiment of the present invention will be described with reference to FIGS. 2 to 4. 2 is a cross-sectional view of the electrical conductivity measuring apparatus according to an embodiment of the present invention, Figure 3 is a perspective view of the electrical conductivity measuring apparatus according to an embodiment of the present invention, Figure 4 is an electrical conductivity measuring apparatus according to an embodiment of the present invention Is an example of mounting.

As shown in Figures 2 to 4, the electrical conductivity measuring apparatus 10 according to an embodiment of the present invention is the first and second electrode (111, 112), the fixing portion 210, the first and second spring ( 121, 122, a printed circuit board 180, an O-ring 230, a mechanism 220, and a fastening part 240.

The first and second electrode rods 111 and 112 may have a vertical cross section and may have a cylindrical shape, a square shape, a polygon shape, and the like.

The first and second electrode rods 111 and 112 have upper portions thereof seated on the mechanism 220 by cross transverse, and are in contact with the first and second springs 121 and 122 to contact the first and second springs 121 and 122. ) Is electrically connected. At this time, it is assumed that the upper portions of the first and second electrode rods 111 and 112 are upper portions of the cross lateral cross and the lateral cross, and the lower portions of the first and second electrode rods 111 and 112 are lower portions of the cross lateral cross.

At least a portion of the lower part of the first and second electrode rods 111 and 112 is surrounded by the fixing part 210, and the rest of the lower part is positioned at the lower part of the fixing part 210 to pipe together with a part of the fixing part 210. Submerged in my coolant.

The fixing part 210 wraps around at least a portion of the first and second electrode rods 111 and 112, and passes through the coupling hole of the pipe together with the first and second electrode rods 111 and 112 to be inserted into the pipe. Lose. At this time, the coupling hole 250 may be configured in a shape corresponding to the circumference of the fixing portion 210 to reduce the gap when the fixing portion 210 is fitted.

The fixing part 210 is fixed to the device 220 and may be made of the same material as the device 220. As shown in FIG. 2, the fixing part 210 may include a groove for fixing the O-ring 230.

O-ring 230 is a member (for example, rubber ring) of a rubber material surrounding the circumference of the fixing portion 210, and prevents the gap between the fixing portion 210 and the coupling hole 250, so that the coolant does not leak through the gap Defend At this time, the O-ring 230 is inserted into a groove for fixing the O-ring 230 of the fixing portion 210 is fixed.

The first and second springs 121 and 122 are elastic members made of a conductive material, one end of which is fitted to the upper portions of the first and second electrode bars 111 and 112, and the other end of the first and second springs 121 and 122. ) To electrically connect the first and second electrode rods 111 and 112 to the controller 140.

The printed circuit board 180 includes first and second connectors 131 and 132, a controller 140, a transmitter 160, and a connector 170 (see FIG. 1).

In detail, the controller 140 is connected to the first and second electrode rods 111 and 112 through the first and second connectors 131 and 132 and the first and second springs 121 and 122. By supplying alternating current to the first and second electrode rods (111, 112) to measure the electrical conductivity of the cooling water, and converts the data of the vehicle network protocol through the transmitter 160, and transmits to the vehicle network connected by the connector 170 .

The mechanism 220 is coupled to the fixing unit 210 to fix the first and second electrode rods 111 and 112 together with the fixing unit 210, and the printed circuit board 180, the first and second springs 121. , 122) inside and protected from dust and the like. In this case, the mechanism 220 and the fixing part 210 may be one component.

The instrument 220 includes a fastening part 240 (for example, a bush) for fastening a fixing member (for example, a bolt) for fixing the conductivity measuring device 10 from the outside.

For example, as shown in FIG. 3, when the mechanism 220 is generally rectangular in shape and includes a portion extending outwardly in the shape of a wing at the side of the square, the fastening part 240 penetrates up and down the portion extending outwardly in the shape of a wing. Is the nut in the hole. Therefore, the conductivity measuring apparatus 10 may be fixed to one region of the fuel cell vehicle by a bolt fastened to the nut.

As described above, the present invention includes an electrode, a controller, and a transmitter in one mechanism, and electrically connects the electrode and the controller by a spring, thereby reducing the inconvenience and failure rate of the conventional assembly / manufacturing process in which the soldering and cable processes are performed. It can be improved, the product size can be reduced, and the implementation cost can be reduced.

In addition, the present invention can be connected to the coupling hole to prevent the leakage of the coolant through the coupling hole by adding an O-ring made of a rubber material blocking the gap of the coupling hole.

In addition, the present invention does not need to be equipped with a temperature sensor by applying the temperature of the cooling water together, and transmit electrical conductivity to the vehicle through the vehicle network to be robust to noise, and easily transmit and receive diagnostic information (Diagnosis) can do.

An apparatus and method for controlling the electroconductive device (or electroconductive sensor) having the above configuration will be described in detail with reference to FIGS. 5 and 6. 5 is a block diagram showing a control device of the conductivity sensor according to another embodiment of the present invention, Figure 6 is a flow chart illustrating a control method of the conductivity sensor according to another embodiment of the present invention.

It will be understood that the control device of the conductivity sensor described below shows a specific configuration of the controller 140 shown in FIG. 1. As shown in FIG. 5, the control device according to another embodiment of the present invention includes an AC signal generator 141, an electrical conductivity output measurer 142, a temperature signal measurer 143, and a self-diagnostic unit 144. , CAN communication conversion unit 145 is configured.

An input terminal (DC / DC converter) for supplying power to the control device, and an output terminal for converting the measured electrical conductivity and temperature signal into data corresponding to the CAN communication protocol and outputting the electrode unit (for example, AC It is insulated from the signal generator 141, the electrical conductivity signal output measuring unit 142, and the temperature signal measuring unit 143. As a result, the electrode unit may obtain a high quality and stable measuring signal.

The AC signal generator 141 generates an AC signal for measuring electrical conductivity and supplies the generated AC signal to the first and second electrode rods 111 and 112 (S610). The AC signal supplied to the electrode periodically changes the polarity of the two electrodes, thereby preventing the cooling water from being electrolyzed and preventing the surface of both electrodes from being deposited with decomposed ions or the like.

In the first and second electrode rods 111 and 112 receiving the AC signal, an AC signal flows to the coolant passing between the two electrode rods, and the electric conductivity signal output measuring unit 142 detects the electric conductivity by using the AC signal. S620). Since the method of detecting electrical conductivity has been described above with reference to Equation 1, a detailed description thereof will be omitted.

The electrical conductivity signal output measuring unit 142 performs a trimming process in order to reduce an error in manufacturing error of a single product, an error in assembly of a product, and an output characteristic deviation (S630). At this time, the electrical conductivity signal output measuring unit 142 uses the raw data of the digital signal for the electrical conductivity obtained by the AC signal at both electrodes.

 The trimming process for the measured conductivity uses the characteristic curve of the conductivity sensor used. As shown in FIG. 7, the representative characteristic curve is a characteristic curve calculated by averaging raw data measured for each conductivity solution of a specified conductivity value for a plurality of specific conductivity sensors. It is representative and used as a basic characteristic curve for mass production.

Specifically, measurements were made on 25 pcs of product and 10 points (3, 6, 10, 15, 20, 25, 30, 35, 40, 50 uS / cm) solutions for initial sample fabrication and evaluation of conductivity sensors. The characteristic curve obtained by averaging the original raw data is extracted as a representative characteristic curve, and the verification is performed by additionally measuring the original data and checking the variation of the characteristic curve in order to verify the representative characteristic curve.

As shown in FIG. 8, the trimming process for the measured electrical conductivity measures the electrical conductivity raw data for a representative conductivity solution (eg, 3 points) selected at the time of manufacture of each product against the measured representative characteristic curve. After calculating the trimming factor for the representative characteristic curve, a specific trimming value corresponding to the characteristic curve is programmed into each conductivity sensor to complete an output signal for compensating the deviation of the product. .

The temperature signal measuring unit 143 measures the temperature of the cooling water passing between the two electrodes 111 and 112 (S640).

The self-diagnostic unit 144 detects abnormal operation of the AC signal generator 141, the electrical conductivity signal output measuring unit 142, and the temperature signal measuring unit 143. After transmitting, the number of reply messages to the transmitted message is counted, and self-diagnosis is performed (S650).

The detected electrical conductivity signal, the temperature signal and the self-diagnosis signal are converted into protocol data for CAN communication by the CAN communication converter 145 (S660). The converted data is transmitted to the vehicle network connected to the connector 170 through the transmitter 160.

While the present invention has been described in detail with reference to the accompanying drawings, it is to be understood that the invention is not limited to the above-described embodiments. Those skilled in the art will appreciate that various modifications, Of course, this is possible. Accordingly, the scope of protection of the present invention should not be limited to the above-described embodiments, but should be determined by the description of the following claims.

Claims (7)

delete And an input terminal for supplying power to the control device, an electrode unit for measuring electrical conductivity and temperature, and an output terminal for converting the measured electrical conductivity and temperature signal into data corresponding to a CAN communication protocol and outputting the data. And the output terminal is a device for controlling an conductivity sensor having a structure in a state of being electrically insulated from the electrode portion,
The electrode unit AC signal generating unit for generating an AC signal for measuring the electrical conductivity, an electrical conductivity signal output measuring unit for detecting the electrical conductivity by flowing the AC signal to the cooling water, a temperature signal measuring unit for detecting the temperature of the cooling water and And a self-diagnostic unit for detecting an abnormality of the AC signal generator, the electric conductivity signal output measuring unit, and the temperature signal measuring unit.
The self-diagnostic unit transmits a self-diagnosis message to each of the AC signal generator, the electric conductivity signal output measuring unit, and the temperature signal measuring unit, and performs self-diagnosis by counting the number of reply messages to the transmitted message. that
Conductivity sensor control device. The method of claim 2, wherein the electrical conductivity signal output measuring unit,
Performing calibration on the detected conductivity using a specific curve correction value for a built-in representative characteristic curve representing the representative characteristic of the conductivity sensor.
Conductivity sensor control device. delete Generating, by the AC signal generator, an AC signal for measuring electric conductivity; detecting, by the AC signal output measuring unit, the electric conductivity with respect to the coolant using the AC signal; and measuring the temperature of the coolant by the temperature signal measuring unit. A method for controlling an conductivity sensor, comprising: correcting the detected conductivity using the temperature detected by the conductivity signal output measuring unit;
Further comprising a self-diagnosis step for detecting whether the AC signal generating unit, the electric conductivity signal output measuring unit and the temperature signal measuring unit abnormality,
In the self-diagnosis step, a self-diagnosis message is transmitted to each of the AC signal generator, the electric conductivity signal output measuring unit, and the temperature signal measuring unit, and the self-diagnosis is performed by counting the number of reply messages to the transmitted message. To do
Phosphorous conductivity sensor control method. delete The method according to claim 6,
Converting the detected conductivity, temperature signal and self-diagnosis signal into data corresponding to the CAN communication protocol
Electrical conductivity sensor control method further comprising.

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