Control device and communication system

Abstract

A control device is provided that has a simple configuration and is capable of appropriately detecting an abnormality in a system in which power supplies are superimposed. [Solution] The control device 100 includes a communication control unit 110 that processes communication data transmitted from a terminal 200 via a communication cable 300, and a switch unit 124 that controls the power supply to the terminal 200. The control device 100 acquires the communication data via the communication cable 300 and includes a power supply monitoring unit 121 that transmits a detection voltage of passband data obtained by filtering out from the communication data, using a filter 122, a signal in a first frequency band used for processing the communication data in the communication control unit 110. The control device 100 further includes a power supply control unit 123 that determines an abnormality in the power supply based on the detection voltage transmitted from the power supply monitoring unit 121, and controls the switch unit 124 when an abnormality is detected.

Description

[Technical Field]

[0001] The present invention relates to a control device and a communication system. [Background technology]

[0002] Conventionally, in a system that supplies power by superimposing it on a communication cable with the aim of reducing the number and weight of cables in the communication system, a technique for detecting an abnormality in the communication system has been proposed. Patent Document 1 discloses a system related to detecting a fault state in a system for providing power through a communication link. The system related to fault detection disclosed in Patent Document 1 detects an abnormal state of the communication system using a current detection circuit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4790729 Summary of the Invention [Problem to be solved by the invention]

[0004] The system for detecting fault conditions disclosed in Patent Document 1 measures high-side and low-side currents using a high-side current sensing circuit that detects the high-side current and a low-side current sensing circuit that detects the low-side current. Furthermore, the system detects system faults from the difference between the measured high-side and low-side current values. Therefore, voltage drops and power consumption occur due to the sense resistors used in the current sensing circuits, and two highly accurate current sensing circuits are required.

[0005] The present invention has been made in view of the problems inherent in the conventional technology, and an object of the present invention is to provide a control device that has a simple configuration and is capable of appropriately detecting an abnormality in a system in which power supplies are superimposed. [Means for solving the problem]

[0006] A control device according to an embodiment of the present invention includes a communication control unit that processes communication data transmitted from a terminal via a communication cable, a switch unit that controls the power supply to the terminal, a power monitoring unit that acquires the communication data via the communication cable and transmits a detection voltage of passband data obtained by filtering out from the communication data a signal of a first frequency band used for processing the communication data in the communication control unit, and a power control unit that determines an abnormality in the power supply based on the detection voltage transmitted from the power monitoring unit and controls the switch unit if an abnormality is detected.

[0007] A communication system according to another aspect of the present invention includes the above-described control device, a communication cable connected to the control device, and a terminal connected to the communication cable and transmitting communication data to the control device. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a control device that has a simple configuration and is capable of appropriately detecting an abnormality in a system in which power supplies are superimposed. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating a configuration of a communication system according to an embodiment of the present invention. [Figure 2] FIG. 4 is a diagram for explaining a filter function of the control device according to the embodiment. [Figure 3] 3A and 3B are diagrams for explaining signal waveforms of a communication system according to the present embodiment. [Figure 4] 5 is a diagram for explaining abnormality detection in the control device according to the present embodiment. FIG. [Figure 5] 5 is a diagram for explaining abnormality detection in the control device according to the present embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] The communication system 10 and the control device 100 according to this embodiment will be described in detail below with reference to the drawings. Note that the dimensional proportions in the drawings are exaggerated for the sake of explanation and may differ from the actual proportions. In addition, in the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

[0011] (Configuration of communication system 10) 1 is a diagram showing the configuration of a communication system 10 according to this embodiment. The communication system 10 includes a control device 100, a terminal 200, and a communication cable 300 that connects the control device 100 and the terminal 200.

[0012] The control device 100 corresponds to, for example, a control ECU (Electronic Control Unit), and collects communication data sent from the terminals 200 and executes predetermined processing.

[0013] The terminal 200 corresponds to a device that exchanges high-speed communication data, such as a camera or a display. For example, in the case of a camera, the terminal 200 converts a captured image into serial data (serializer) in the communication control unit 210 and transmits it to the control device 100 via the communication cable 300. The power supply device 220 generates power for operating the terminal 200. The terminal 200 also includes a capacitor C2 that has the function of superimposing the communication signal to be transmitted as an AC component onto the power supply voltage.

[0014] The communication cable 300 corresponds to a coaxial cable or twisted pair cable that is generally used in high-speed communication.

[0015] (Configuration of control device 100) The control device 100 includes a communication control unit 110, a power supply device 120, and a power supply Vb. The control device 100 may also include a capacitor C1 between the communication control unit 110 and the communication cable 300, which has the function of removing the DC component of the power supply voltage from the signal (communication data) on the communication cable 300 and extracting only the communication signal.

[0016] The communication control unit 110 processes communication data transmitted from the terminal 200 via the communication cable 300. Specifically, when the terminal 200 is a camera, for example, the communication control unit 110 restores (deserializes) the serial data transmitted from the communication cable 300.

[0017] The power supply device 120 includes a power supply monitor 121 having a filter 122, a power supply control unit 123, and a switch unit .

[0018] The power supply monitoring unit 121 acquires communication data via the communication cable 300, and transmits to the power supply control unit 123 the detected voltage of the passband data obtained by filtering out from the communication data a signal of the first frequency band used for processing the communication data in the communication control unit 110 using a filter 122.

[0019] In the communication system 10 according to this embodiment, the passband data includes a second frequency band having a lower frequency than the first frequency band, and a third frequency band having a higher frequency than the first frequency band.

[0020] 2 is a diagram for explaining the filter function of the communication system 10 according to this embodiment. In the example shown in FIG. 2, the "frequency band handled by the communication control unit" corresponds to the first frequency band used for processing communication data in the communication control unit 110.

[0021] 2, the frequency band of "passband A" corresponds to a second frequency band that is lower in frequency than the first frequency band, and in the example shown in FIG. 2, "passband B" corresponds to a third frequency band that is higher in frequency than the first frequency band.

[0022] The power supply control unit 123 performs control via the switch unit 124 to superimpose the power supplied from the power supply Vb onto the communication cable 300. The switch unit 124 may be configured to include, for example, a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor). The switch unit 124 may also be configured to have a step-up / step-down function (switching power supply).

[0023] 3 is a diagram for explaining signal waveforms in the communication system 10 according to this embodiment. P1 to P3 shown in Fig. 3 correspond to P1 in the terminal 200, P2 of the power supply Vb, and P3 of the communication cable 300 shown in Fig. 1, respectively.

[0024] In the example shown in FIG. 3, a power supply voltage indicated by P2 is superimposed on a communication signal indicated by P1, and is shown as communication data on the communication cable 300 at P3.

[0025] Furthermore, in the communication system 10 according to this embodiment, the power supply control unit 123 determines whether there is an abnormality in the power supply based on the detected voltage transmitted from the power supply monitoring unit 121, and controls the switch unit 124 if it detects that there is an abnormality.

[0026] Specifically, when the power supply control unit 123 determines that the value of the detected voltage in the second frequency band is higher than a predetermined first threshold, it determines that an overvoltage abnormality has occurred and controls the switch unit 124 to stabilize the power supply voltage. In the communication system 10 according to this embodiment, the control to stabilize the power supply voltage is performed, for example, by adjusting (reducing) the gate voltage of the MOSFET of the switch unit 124 to throttle the output and stabilize the voltage at a constant value.

[0027] In addition, in a configuration in which the switch unit 124 is provided with a step-up / step-down function (switching power supply), the power supply control unit 123 may perform control to stabilize the power supply voltage by controlling the step-up / step-down function to maintain the output at a constant voltage in response to an increase or decrease in voltage.

[0028] 4 is a diagram for explaining anomaly detection in the communication system 10 according to the present embodiment. As shown in FIG. 4, when an overvoltage (load dump) occurs in the detection voltage, a gradual voltage fluctuation occurs in the second frequency band, and the detection voltage exceeds the first threshold value.

[0029] In this way, the control device 100 of this embodiment can stabilize the communication system 10 by performing control to stabilize the power supply voltage when there is an abnormality in the second frequency band (passband A) which has a frequency lower than that of the first frequency band.

[0030] Furthermore, when the power supply control unit 123 determines that the value of the detected voltage in the third frequency band is lower than a predetermined second threshold, it determines that an abnormality in the generation of an overcurrent has occurred, and controls the switch unit 124 to turn off and stop the supply of power to the terminal 200.

[0031] 5 is a diagram for explaining abnormality detection in the communication system 10 according to the present embodiment. As shown in FIG. 5, when an overcurrent (dead short) occurs in the detection voltage, a sudden voltage fluctuation occurs, and the detection voltage becomes lower than the second threshold value.

[0032] In this way, the control device 100 according to this embodiment controls to turn off the switch unit 124 when an abnormality is detected in the third frequency band (passband B) that is higher in frequency than the first frequency band. This enables the communication system 10 to prevent the communication cable 300 and the terminal 200 from emitting smoke or catching fire due to an overcurrent (dead short).

[0033] As described above, the power supply control unit 123 determines whether there is an abnormality in voltage fluctuations in both the second frequency band (pass band A) whose frequency is lower than the first frequency band and the third frequency band (pass band B) whose frequency is higher than the first frequency band. This allows the control device 100 according to this embodiment to stabilize the power supply caused by both low frequencies and high frequencies, and to prevent smoke and fire from occurring in the communication cable 300 and the terminal 200.

[0034] The switch unit 124 controls the power supply to the terminal 200 in accordance with a control instruction from the power control unit 123. Specifically, the switch unit 124 performs control to stabilize the power supply and control to turn off the power supply to the terminal 200 based on the control instruction from the power control unit 123.

[0035] As described above, the control device 100 includes a communication control unit 110 that processes communication data transmitted from the terminal 200 via the communication cable 300, and a switch unit 124 that controls the power supply to the terminal 200. The control device 100 acquires the communication data via the communication cable 300 and includes a power supply monitoring unit 121 that transmits a detection voltage of passband data obtained by filtering out from the communication data, using a filter 122, a signal in a first frequency band used for processing the communication data in the communication control unit 110. The control device 100 further includes a power supply control unit 123 that determines an abnormality in the power supply based on the detection voltage transmitted from the power supply monitoring unit 121, and controls the switch unit 124 when an abnormality is detected.

[0036] As a result, the control device 100 according to this embodiment does not need to have two highly accurate current detection circuits, one for the high side and one for the low side, and can appropriately detect abnormalities in the system when power supplies are superimposed with a simple configuration.

[0037] Furthermore, the passband data of the control device 100 may include a second frequency band having a lower frequency than the first frequency band and a third frequency band having a higher frequency than the first frequency band. That is, the power supply control unit 123 determines whether there is an abnormality in voltage fluctuations in both the second frequency band (passband A) having a lower frequency than the first frequency band and the third frequency band (passband B) having a higher frequency than the first frequency band. This enables the control device 100 according to this embodiment to stabilize the power supply due to both low frequencies and high frequencies and to prevent smoke and fire from occurring in the communication cable 300 and the terminal 200.

[0038] Furthermore, when it is determined that the value of the detected voltage in the second frequency band is higher than a predetermined first threshold, the power supply control unit 123 of the control device 100 may determine that an overvoltage abnormality has occurred and control the switch unit 124 to stabilize the power supply voltage. As a result, when an abnormality has occurred in the second frequency band (passband A) whose frequency is lower than that of the first frequency band, the communication system 10 can stabilize the communication system 10 by performing control to stabilize the power supply voltage.

[0039] Furthermore, when the power supply control unit 123 of the control device 100 determines that the value of the detected voltage in the third frequency band is lower than a predetermined second threshold, it may determine that an abnormality in the form of an overcurrent has occurred, and may control the switch unit 124 to turn off and stop the supply of power to the terminal 200. That is, when an abnormality has occurred in the third frequency band (passband B) that has a higher frequency than the first frequency band, the power supply control unit 123 controls to turn off the switch unit 124. This enables the communication system 10 to prevent smoke or fire from occurring in the communication cable 300 or the terminal 200.

[0040] (Other embodiments) Although the embodiments have been described in detail with reference to the drawings, the present embodiments are not limited to the contents described in the above embodiments. Furthermore, the components described above include those that can be easily imagined by a person skilled in the art and those that are substantially the same. Furthermore, the configurations described above can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the configurations can be made without departing from the spirit of the embodiments.

[0041] The features of the control device 100 and the communication system 10 will be described below.

[0042] The control device 100 according to the first aspect includes a communication control unit 110 that processes communication data transmitted from a terminal 200 via a communication cable 300, and a switch unit 124 that controls the supply of power to the terminal 200. The control device 100 acquires the communication data via the communication cable 300 and includes a power supply monitoring unit 121 that transmits a detection voltage of passband data obtained by filtering out from the communication data, using a filter 122, a signal in a first frequency band used for processing the communication data in the communication control unit 110. The control device 100 further includes a power supply control unit 123 that determines an abnormality in the power supply based on the detection voltage transmitted from the power supply monitoring unit 121 and controls the switch unit 124 when an abnormality is detected.

[0043] According to the above configuration, the control device 100 does not need to be provided with two highly accurate current detection circuits for the high side and the low side, and can appropriately detect an abnormality in the system in power supply superposition with a simple configuration.

[0044] The passband data of the control device 100 according to the second embodiment may include a second frequency band having a lower frequency than the first frequency band, and a third frequency band having a higher frequency than the first frequency band.

[0045] According to the above configuration, the power supply control unit 123 determines whether there is an abnormality in voltage fluctuations in both the second frequency band (pass band A) whose frequency is lower than the first frequency band and the third frequency band (pass band B) whose frequency is higher than the first frequency band. This enables the control device 100 according to this embodiment to stabilize the power supply caused by both low frequencies and high frequencies, and to prevent smoke and fire from occurring in the communication cable 300 and the terminal 200.

[0046] When the power supply control unit 123 of the control device 100 according to the third aspect determines that the value of the detected voltage in the second frequency band is higher than a predetermined first threshold, it may determine that an overvoltage abnormality exists and control the switch unit 124 to stabilize the power supply voltage.

[0047] According to the above configuration, when an abnormality occurs in the second frequency band (passband A) that has a lower frequency than the first frequency band, the control device 100 can stabilize the communication system 10 by performing control to stabilize the power supply voltage.

[0048] When the power supply control unit 123 of the control device 100 according to the fourth aspect determines that the value of the detected voltage in the third frequency band is lower than a predetermined second threshold, it may determine that an abnormality in the generation of an overcurrent has occurred, and may control the switch unit 124 to turn off and stop the supply of power to the terminal 200.

[0049] According to the above configuration, the power supply control unit 123 performs control to turn off the switch unit 124 when an abnormality occurs in the third frequency band (passband B) that is higher in frequency than the first frequency band. This enables the communication system 10 to prevent the communication cable 300 and the terminal 200 from emitting smoke or catching fire.

[0050] The communication system 10 according to the fifth aspect includes the above-mentioned control device 100, a communication cable 300 connected to the control device 100, and a terminal 200 connected to the communication cable 300 and transmitting communication data to the control device 100.

[0051] According to the above configuration, the communication system 10 does not need to have two highly accurate current detection circuits for the high side and the low side, and can appropriately detect an abnormality in the system when power is superimposed with a simple configuration. [Explanation of symbols]

[0052] 10. Communication Systems 100 control device 110, 210 Communication control unit 120, 220 power supply 121 Power supply monitoring section 122 filters 123 Power supply control unit 124 Switch section 200 devices 300 Communication Cable C1, C2 capacitors

Claims

1. a communication control unit that processes communication data transmitted from the terminal via a communication cable; a switch unit for controlling power supply to the terminal; a power supply monitoring unit that acquires the communication data via the communication cable and transmits a detection voltage of passband data obtained by filtering out, from the communication data, a signal of a first frequency band used for processing the communication data in the communication control unit using a filter; a power supply control unit that determines an abnormality in the power supply based on the detected voltage transmitted from the power supply monitoring unit, and controls the switch unit when an abnormality is detected; A control device comprising:

2. The control device according to claim 1 , wherein the passband data includes a second frequency band having a lower frequency than the first frequency band and a third frequency band having a higher frequency than the first frequency band.

3. 3. The control device according to claim 2, wherein the power supply control unit determines that an overvoltage abnormality exists when it determines that the value of the detected voltage in the second frequency band is higher than a predetermined first threshold, and controls the switch unit to stabilize the power supply voltage.

4. 3. The control device according to claim 2, wherein when the power supply control unit determines that the value of the detected voltage in the third frequency band is lower than a predetermined second threshold, the power supply control unit determines that an abnormality has occurred due to an overcurrent, and controls the switch unit to turn off and stop power supply to the terminal.

5. The control device according to any one of claims 1 to 3; the communication cable connected to the control device; a terminal connected to the communication cable and transmitting the communication data to the control device; A communication system comprising:

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