KR102204239B1 - Intrinsic safety wireless communication device for use in explosive atmospheres - Google Patents

Abstract

The present specification relates to a wireless communication device for intrinsically safe explosion protection. This specification relates to a wireless communication unit for performing wireless transmission/reception, a super capacitor connected between an external power source and the wireless communication unit, receiving power from the external power source, charging electric charges, and outputting a voltage required for wireless transmission and reception to the wireless communication unit, and It provides a wireless communication device including a voltage measuring unit that measures the voltage of the super capacitor and controls to apply the output voltage of the super capacitor to the wireless communication unit for a predetermined time when the measured voltage is within a preset reference range.

Description

Intrinsically safe explosion-proof wireless communication devices used in explosive places {INTRINSIC SAFETY WIRELESS COMMUNICATION DEVICE FOR USE IN EXPLOSIVE ATMOSPHERES}

The present invention relates to a wireless communication device, and more particularly, to a wireless communication device for intrinsically safe explosion protection.

Today's wireless communication (CDMA, WCDMA, LTE, etc.)modem systems provide sensors and communication functions to objects around us to collect and share information like living organisms, allowing them to interact with intelligent networking technologies (e.g., M2M). (machine to machine), IOT (internet of things)) is considered one of the key elements.

Accordingly, a modem, which is a wireless communication unit, is attached to equipment required for control, smart grid, method, etc. and connected to the network.

In general, in places where there is a risk of explosion due to combustible materials such as industrial sites or laboratories, explosion-proof regulations must be satisfied so that electrical and electronic equipment such as wireless communication modem systems do not become ignition sources.

In general, one of the methods of implementing the intrinsically safe explosion-proof function is to limit the total amount of energy supplied to the wireless communication unit. In this case, the method of limiting the total amount of energy in a circuit with a fixed driving voltage is to limit the current consumption. will be.

Patent Publication No. 10-2015-0110248 relates to a wireless communication modem system, in which a voltage output from a power supply is lowered and applied to a capacitor, and the capacitor reduces the amount of current consumption below a set current limit, thereby providing an intrinsically safe explosion-proof function. I tried to implement it. However, if the current value for driving the wireless communication unit, that is, the RF chip or the RF module, has a value higher than the intrinsically safe explosion-proof current limit, there is a limit that wireless transmission/reception does not operate normally.

Therefore, in the present technical field, a communication system capable of stably driving a modem is required even when the current value for driving the RF chip or RF module is higher than the intrinsically safe explosion-proof current limit.

Patent Document 1: Korean Patent Application Publication No. 10-2015-0110248

An object of the present invention is to provide a wireless communication circuit that satisfies intrinsically safe explosion-proof regulations.

Another technical problem of the present invention is to improve the satisfaction of users and manufacturers by providing an intrinsically safe explosion-proof function to the wireless communication circuit to expand the area of use of the wireless communication circuit.

Another technical object of the present invention is to provide a wireless communication circuit capable of stably transmitting and receiving wirelessly even when the current value for stably driving the RF chip or RF module is higher than the limit current reference value for implementing intrinsically safe explosion protection. .

According to an aspect of the present invention, a wireless communication system for intrinsically safe explosion protection is provided. The wireless communication device includes a wireless communication unit that performs wireless transmission and reception, a super capacitor that charges power until a predetermined voltage is reached, and supplies power required for wireless transmission and reception to the wireless communication unit, and a voltage of the super capacitor is measured at a predetermined period. When the measured voltage is within a preset reference range, it is implemented including a voltage measuring unit that controls to apply the output voltage of the super capacitor to the wireless communication unit for a predetermined time.

According to another aspect of the present invention, the wireless communication system selectively receives a high-frequency signal according to a specific frequency band and transmits it to the wireless communication unit, or receives a signal transmitted from the wireless communication unit to provide a high-frequency signal according to a specific frequency band. It is implemented by further comprising an antenna unit radiating into the air and a blocking capacitor unit including at least one capacitor connected in series between the wireless communication unit and the antenna unit.

According to another aspect of the invention, the at least one capacitor is configured to have a fault-free rating and a spacing distance.

According to another aspect of the present invention, the wireless communication device is provided between the wireless communication unit and the connector, and a connector providing a terminal that can be connected by wire so that the wireless communication unit and the external device transmit and receive signals to each other. It is implemented by further including a current limiting resistor that reduces the amount of current applied to an external device connected through the connector to be less than a preset current limit.

According to another aspect of the present invention, the wireless communication device further comprises a power supply unit for supplying power to the super capacitor, and a reverse current prevention unit composed of at least one diode connected in series and parallel between the power supply unit and the super capacitor. Included and implemented.

According to another aspect of the invention, the at least one diode is configured to have a fault-free rating and a spacing distance.

According to another aspect of the present invention, the wireless communication device includes an IC-type E-SIM chip on the substrate of the wireless communication circuit. It is implemented by molding together with the substrate.

The wireless communication device according to the present invention may satisfy intrinsically safe explosion-proof regulations. In addition, a wireless communication device capable of stably performing wireless transmission/reception may be provided even when a current value for stably driving an RF chip or an RF module is higher than an intrinsically safe explosion-proof current reference value.

1 shows a schematic structure of a wireless communication device according to an embodiment of the present invention.
2 shows an example of current values that can be consumed to drive the wireless communication unit of the present invention.
3 shows characteristics of current consumption that may appear when a super capacitor, a voltage measuring unit, and a switch unit according to the present invention are not applied.
4 shows a change over time of a voltage that can be measured at a super capacitor in a wireless communication device according to the present invention.
5 and 6 show an arrangement relationship between a substrate and a core of a wireless communication modem according to the prior art.
7 shows an arrangement relationship between a substrate and an e-core of a wireless communication modem according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments disclosed below. In addition, parts irrelevant to the present invention are omitted in the drawings in order to clearly disclose the present invention, and the same or similar reference numerals denote the same or similar components.

Objects and effects of the present invention may be naturally understood or more apparent by the following description, and the objects and effects of the present invention are not limited only by the following description.

Objects, features and advantages of the present invention will become more apparent through the following detailed description. In addition, in describing the present invention, when it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 shows a schematic structure of a wireless communication device according to an embodiment of the present invention.

Referring to FIG. 1, a wireless communication system 100 according to the present invention includes a wireless communication device 170 having a power supply unit 110, a connector 150, and an antenna unit 130.

The power supply unit 110 generates a DC voltage of about 5 to 12V and supplies it to the wireless communication device 170, and provides a voltage required for driving the wireless communication device 170. The power supply unit 110 may be located outside the wireless communication device 170 and may be located inside the wireless communication device 170 in some cases. In addition, the power supply unit 110 generates and provides a DC voltage that satisfies the intrinsically safe explosion-proof standard. The power supply unit 110 may be a constant power source, a battery, or a gas-related device connected to the wireless communication device 170.

The antenna unit 130 is connected to the blocking capacitor unit 179, and radiates the signal of the specific frequency band input from the other end of the blocking capacitor unit 179 to the outside or transmits a radio signal received from the outside to the blocking capacitor unit. Output as (179). In this case, the antenna unit 130 may be implemented as a so-called “antenna” mounted on the substrate of the wireless communication device 170. Alternatively, the antenna unit 110 may be implemented as an external antenna.

The connector 150 has one end connected to the current limiting resistor 180 of the wireless communication device 170, and the other end providing a terminal for connecting an external device to receive a signal received from the current limiting resistor 180. It transmits to an external device or a signal received from an external device to the current limiting resistor.

The wireless communication device 170 is connected to the power supply unit 110 and the connector 150, and the circuit input voltage limiting unit 171, the regulator 172, the reverse current prevention unit 173, the super capacitor 174, A voltage measurement unit 175, a switch unit 176, a wireless communication unit 177, an E core 178, a blocking capacitor unit 179, and a current limiting resistor 180 may be included.

The input voltage limiting unit 171 includes at least one Zener diode D1 and D2 connected in parallel between the power supply unit 110 and the regulator 172 when there is a concern that the input power exceeds the intrinsically safe voltage required. can do. The input voltage limiting unit 171 is configured to have a failure-free rating, a separation distance, and a structure according to related regulations.

The regulator 172 converts the voltage (eg, 5V to 12V) of the power supply unit 110 applied through the input voltage limiting unit 171 into a predetermined size (eg, 3.3V) and outputs it.

The reverse current prevention unit 173 includes at least one diode D3, D4, D5, D6, D7, and D8 connected in series and parallel between the regulator 172 and the super capacitor 174. The at least one diode D3, D4, D5, D6, D7, D8 is configured to have a fault-free rating and a separation distance.

The reverse current prevention unit 173 prevents the output current from flowing in the reverse direction, that is, the direction of the regulator 172 by increasing the voltage of the super capacitor 174 as charges are accumulated in the super capacitor 174.

On the other hand, when the reverse current prevention unit 173 has a structure in which the at least one diode (D3, D4, D5, D6, D7, D8) is connected only in series, a voltage drop at the rear end occurs due to a resistance component, and the wireless communication unit In order to satisfy the operating voltage of, there is a problem that the input voltage must be compensated for and applied as much as the drop voltage. This requires high energy in the explosion-proof design of the host side to which the wireless communication modem is applied, so the design is limited.

However, since the at least one diamond (D3, D4, D5, D6, D7, D8) of the reverse current preventing unit 173 is connected in series and parallel, the voltage drop is reduced, thereby solving the above problem.

The super capacitor 174 includes at least one capacitor C1 and C2 connected in parallel between the reverse current prevention unit 173 and the ground.

The super capacitor 174 receives power to stably operate the wireless communication unit 177, charges electric charges, and outputs a voltage required for wireless transmission/reception to the wireless communication unit 177. That is, the super capacitor 174 receives power provided from the power supply unit 110 through the power regulator 172 and charges the electric charge until it reaches a predetermined voltage for driving the wireless communication unit 177, and the constant When the voltage is reached, current is supplied to the wireless communication unit 177. A determination as to whether the super capacitor 174 has reached a certain voltage for driving the wireless communication unit 177 is performed by the voltage measurement unit 175 described below.

The voltage and/or current input to the wireless communication device 170 may be limited to less than or equal to the voltage and/or current limit required by regulations related to intrinsically safe explosion protection. For this reason, when the minimum voltage and/or current required for driving the wireless communication unit 177 is not supplied, the wireless communication unit 177 may not operate normally. Therefore, the super capacitor 174 capable of operating the wireless communication unit 177 normally even when voltage and/or current is input to the wireless communication device 170 within a range not exceeding the allowable reference value for the intrinsically safe explosion protection. It is equipped. The super capacitor 174 accumulates charge by receiving a voltage and/or current below the threshold for implementing the intrinsically safe explosion-proof reference voltage and/or current for a certain period of time, and then accumulating the voltage and the voltage required for driving the wireless communication unit 177 /Or supply current.

Voltage and/or current may be stably supplied to the wireless communication unit 177 by the super capacitor 174. In addition, even if the output voltage and/or current of the voltage regulator 172 is low, the voltage and/or current applied to the wireless communication unit 177 is reduced below the minimum operating voltage and/or current required for the operation of the wireless communication unit 177 Because it prevents the stable operation of the wireless communication unit 177 is guaranteed.

The voltage measurement unit 175 measures the voltage output from the super capacitor 174 at a certain period and compares it with a preset reference voltage (that is, the rated driving voltage of the wireless communication unit 177), when the output voltage is within the reference range. A control signal (for example, a high level signal H) for operating the switch unit 176 is output to the switch unit 176 for a certain period of time, and the operation of the switch unit 176 is stopped when the certain time has elapsed. A signal to be stopped (for example, a low level signal L) is output to the switch unit 176.

In this voltage measurement unit 175, the output voltage of the super capacitor 174 is applied to one of the two input terminals (for example, a non-inverting input terminal), and a reference voltage is applied to the other input terminal (for example, an inverting input terminal). May be an applied comparator.

The switch unit 176 is a switching element that is turned on or off in a state of a control signal output from the voltage measuring unit 175, for example, a metal oxide semiconductor field effect transistor (MOSFET, metal). oxide semiconductor field effect transistor), but is not limited thereto.

The switch unit 176 has a control terminal (eg, a gate terminal) connected to the output terminal of the voltage measuring unit 175 and an input terminal (eg, a source terminal) connected to the output terminal of the super capacitor 174 Is connected, and an output terminal (eg, a drain terminal) is connected to an input terminal of the wireless communication unit 177.

The switch unit 176 is turned on when a control signal in a high level state is input from the voltage measurement unit 175 to the control terminal, and transmits the output voltage of the super capacitor 174 to the wireless communication unit 177, and conversely, the voltage measurement unit 175 When the control signal in the low level state is input from) to the control terminal, it is turned off and the output voltage of the super capacitor 174 transmitted to the wireless communication unit 177 is cut off.

By the operation of the switch unit 176, since the output voltage from the super capacitor 174 is supplied to the wireless communication unit 177 only in a safe state, that is, greater than the reference voltage, the wireless communication unit 177 is supplied with a stable voltage. Operation is also performed stably.

Meanwhile, a timing or period in which the voltage measurement unit 175 measures a voltage and turns on the switch unit 176 may be set in consideration of a timing or period at which the wireless communication unit 177 transmits and receives a signal. For example, a period in which the energy stored in the super capacitor 174 is supplied by turning on the switch unit 176 may be set to coincide with a period in which the wireless communication unit 177 performs signal transmission/reception. Accordingly, the super capacitor 174 can provide energy (or power) continuously accumulated at a low current to the wireless communication unit 177 at the timing, whereby the wireless communication unit 177 consumes power required for wireless transmission/reception. can do. However, since the energy stored in the supercapacitor 174 is temporarily discharged after the above timing, the supercapacitor 174 needs to accumulate charge again until it can supply power required for driving the wireless communication unit 177. .

If the wireless communication unit 177 transmits a signal in a state in which energy is not sufficiently stored in the super capacitor 174, the signal may be transmitted with a power lower than the normal standard, and eventually communication may fail. In this case, the wireless communication unit 177 attempts to retransmit the signal by a retransmission algorithm according to the wireless communication standard. At this time, the wireless communication unit 177 uses the residual energy of the super capacitor 174 again, so in the end, the super capacitor 174 ) Is unable to continuously supply power required for communication of the wireless communication unit 177, and the wireless communication unit 177 continues to fall into an irrecoverable state in which the vicious cycle of failure of communication is repeated.

Therefore, at the timing at which the wireless communication unit 177 transmits and receives the next signal, if the supercapacitor 174 is measured to be less than the reference voltage as a result of the measurement by the voltage measurement unit 175, the switch unit 176 is turned off and the supercapacitor The output of the voltage and/or current of 174 is cut off, and the wireless communication unit 177 waits until the super capacitor 174 reaches the reference voltage or higher in the next voltage measurement period without performing transmission and reception. Accordingly, a problem in which the super capacitor 174 and the wireless communication unit 177 fall into an irrecoverable state can be prevented.

2 to 4 are graphs showing characteristics of current consumption consumed at the rear end of the power supply unit, and FIG. 2 illustrates an example of current values that can be consumed to drive the wireless communication unit 177 of the present invention, 3 shows characteristics of current consumption that may appear when the super capacitor 174, the voltage measurement unit 175, and the switch unit 176 according to the present invention are not applied. 2 and 3, a low level of current is supplied from the regulator 172 in order to meet the intrinsically safe explosion-proof standards, but current for stably driving the wireless communication unit 177 of the peak current level of FIG. Since the value is not satisfied, the wireless transmission/reception operation of the wireless communication unit 177 may not be normally performed.

4 shows a change over time of a voltage that can be measured by a super capacitor 174 in a wireless communication device according to the present invention. Referring to FIG. 4, the super capacitor 174 is charged by the current supplied from the regulator 172, and after a certain period of time, the super capacitor is charged above a predetermined voltage set by the voltage measuring unit 175. Accordingly, the switch is turned on so that the output voltage of the super capacitor 174 is transmitted to the wireless communication unit 177, and the wireless communication unit 177 stably performs communication.

Referring back to FIG. 1, the wireless communication unit 177 is composed of an RF chip or an RF module, and performs wireless transmission/reception using power applied from the super capacitor 174. The wireless communication unit 177 includes Internet of Things (IoT) such as Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE) or Long Range (LoRa), NB-IoT (Narrowband-IoT). ) Wireless transmission and reception can be performed in a wireless communication method.

In the E-core 178, an e-core (eSIM) chip in the form of an IC is soldered onto the substrate of the wireless communication device 170 and molded together with the substrate.

5 and 6 show an arrangement relationship between the substrate and the core of the wireless communication modem according to the prior art, and FIG. 7 shows the arrangement relationship between the substrate and the e-core of the wireless communication modem according to the present invention.

Referring to FIG. 5, in the conventional wireless communication modem system, in order not to mold a USIM socket, the conventional wireless communication modem system molds between the PCB of the modem and the SIM socket by spaced apart from the outside. However, in this case, in order to satisfy the intrinsically safe explosion-proof regulations, an additional protection circuit is required to limit the risk of explosion due to failure of the SIM circuit exposed outside the molding.

Meanwhile, referring to FIG. 6, according to another prior art, in order to meet the intrinsically safe explosion-proof regulations without an additional protection circuit, the SIM socket is brought into contact with the modem PCB and molded together. However, in this case, the molding liquid penetrates into the contact surface of the SIM socket and the SIM chip, causing unstable contact of the contact point, causing a defect in which the SIM is not recognized. Therefore, in order to prevent this, there is a problem in that the SIM socket must be first coated with a coating solution having low penetration and then molded.

In the present invention for solving these problems, referring to FIG. 7, when an IC-type eSIM chip is soldered to a board and molded instead of a SIM socket and a SIM chip, the above-described problems can be solved. The factor of decreases.

Referring back to FIG. 1, the blocking capacitor unit 179 has one end connected to the wireless communication unit 177 and filters a signal input from the wireless communication unit to transmit a signal of a specific frequency band to the antenna unit 130 connected to the other end. Print. The blocking capacitor unit 179 includes at least one capacitor C3 and C4 connected in series having a rated and spaced distance in a structure without failure according to related regulations. The blocking capacitor unit 179 is an electrolytic capacitor or a tantalum capacitor. It is preferably made of a solid gene having high reliability, not. An antenna having a structure that is directly connected to the wireless communication unit 177 without passing through the conventional blocking capacitor unit 179 is molded together with the communication modem circuit so that heat or spark is not radiated to the outside in order to meet the intrinsically safe explosion-proof standards. Must do. Therefore, there are many limitations in the antenna design, such as it is impossible to use a non-explosion-proof external antenna, there is a size limit for the molding structure, and the molding material becomes a radio wave interference element and performance is degraded. However, in the present invention, since the blocking capacitor 179 is provided between the antenna unit 130 and the wireless communication unit 177 as described above, since the antenna of the antenna unit 130 does not need to be molded, the product production process is efficient. And it becomes simpler. In addition, since there is no restriction on the antenna design, the housing design is easy, and an external antenna can be used, so that an antenna with high gain can be used. In addition, since the antenna does not need to be molded together with the communication modem circuit, there is no deterioration in RF performance due to the molding material.

The current limiting resistor 180 has one end connected to the wireless communication unit 177 and the other end connected to the connector 150, so that the amount of current input from the wireless communication unit 177 is limited to a preset current limit value or less, The amount of the current output to 150 or input from the connector 150 is limited to less than or equal to a preset current limit and transmitted to the wireless communication unit 177. The current limiting resistor 180 has a rating and a separation distance in a structure that does not have a fault according to related regulations. The IoT communication modem system is connected to an external device through a connector. At this time, the current limiting resistor 180 is provided in order to reduce the amount of current applied to the external device below a set current limit value to satisfy the total amount of energy required for intrinsically safe explosion protection.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains will be able to make various modifications and variations without departing from the essential characteristics of the present invention. Accordingly, the embodiments of the present invention described above may be implemented separately or in combination with each other.

Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain the technical idea, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

Claims (8)

In the wireless communication device for intrinsically safe explosion protection,
A wireless communication unit that performs wireless transmission and reception;
A super capacitor connected between an external power source and the wireless communication unit, receiving power from the external power source, charging electric charges, and outputting a voltage required for wireless transmission and reception to the wireless communication unit;
A voltage measuring unit that measures the voltage of the super capacitor and controls to apply the output voltage of the super capacitor to the wireless communication unit for a predetermined time when the measured voltage is within a preset reference range;
A power supply unit supplying power to the super capacitor; And
A reverse current prevention unit comprising a plurality of diodes connected in series and parallel to each other between the power supply unit and the super capacitor, and blocks current from moving from the super capacitor to the power supply unit
Wireless communication device comprising a.
The method of claim 1, wherein the wireless communication device,
At least one blocking capacitor unit having one end connected to the wireless communication unit and filtering a signal input from the wireless communication unit to output a signal of a specific frequency band to the other end; And
An antenna unit connected to the other end of the blocking capacitor unit and radiating a signal of the specific frequency band input from the other end of the blocking capacitor unit to the outside or outputting a radio signal received from the outside to the other end of the blocking capacitor unit
A wireless communication device, characterized in that it further comprises.
The wireless communication device of claim 2, wherein the at least one capacitor has a rating and a separation distance in a structure without failure.
The method of claim 1, wherein the wireless communication device,
Since one end is connected to the wireless communication unit, the size of the current input from the wireless communication unit is limited to less than a preset current limit and output to the other end, or by limiting the amount of current input from the other end to less than a preset current limit. A current limiting resistor transmitted to the wireless communication unit; And
One end is connected to the current limiting resistor, and the other end is provided with a terminal for connecting an external device to transmit a signal received from the current limiting resistor to the external device, or to limit the current to a signal received from the external device. Connector to transfer to resistor
A wireless communication device, characterized in that it further comprises.
delete The wireless communication device according to claim 1, wherein the at least one diode has a fault-free rating and a separation distance.
The wireless communication device according to claim 1, wherein the wireless communication device is molded together with the circuit board by soldering an E-SIM chip in the form of an IC on a circuit board.
The method of claim 1, wherein the wireless communication device,
When an input terminal is connected to the super capacitor, an output terminal is connected to the wireless communication unit, a control terminal is connected to the voltage measurement unit, and the measured voltage of the voltage measurement unit is within the preset reference range, the voltage measurement And a switch unit for applying a voltage input from the super capacitor to the wireless communication unit under negative control.

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