Control device and status monitoring device

Abstract

To provide a control device and a condition monitoring apparatus, capable of suppressing power consumption in a device.SOLUTION: In a condition monitoring system 100, a control device 120 in a condition monitoring apparatus 110 controls a sensor 130 that operates by power supplied from a generator via an electric circuit including a rectifying and smoothing circuit 114 for converting alternating current power output from the generator 102 into direct current power and a converter 116 for transforming an output voltage of the rectifying and smoothing circuit. The control device includes: a first generation unit 122 for generating a first trigger signal on the basis of the output voltage of the rectifying and smoothing circuit; a second generation unit 124 for generating a second trigger signal on the basis of the output voltage of the converter; and a controller 126 that switches an operation mode of the sensor between a sleep mode and an active mode on the basis of the first trigger signal and the second trigger signal.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to a control device and a status monitoring device. [Background technology]

[0002] Vibration power generators generate electricity by utilizing environmental vibrations (e.g., vibrations from cars or trains, or vibrations from rain hitting the ground). Electricity generated by vibration power generators is expected to replace power sources (e.g., batteries) used in sensor devices such as condition monitoring devices.

[0003] In a system in which a vibration power generator and a condition monitoring device are connected, in order to operate the condition monitoring device stably, the average power generated by the vibration power generator needs to be greater than the average power consumption of the condition monitoring device. Therefore, it is important to reduce the average power consumption of the condition monitoring device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6193322 Summary of the Invention [Problem to be solved by the invention]

[0005] The problem to be solved by the present invention is to provide a technique capable of reducing power consumption in an apparatus. [Means for solving the problem]

[0006] A control device according to one embodiment controls a sensor that operates with power supplied by a generator via an electric circuit that includes a rectifying and smoothing circuit that converts AC power output from the generator into DC power and a converter that transforms the output voltage of the rectifying and smoothing circuit, and includes a first generating unit that generates a first trigger signal based on the output voltage of the rectifying and smoothing circuit, a second generating unit that generates a second trigger signal based on the output voltage of the converter, and a controller that switches the operation mode of the sensor between a sleep mode and an active mode based on the first trigger signal and the second trigger signal. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a condition monitoring system according to an embodiment. [Diagram 2] FIG. 2 is a diagram illustrating the operation of the control device shown in FIG. [Diagram 3] FIG. 3 is a diagram illustrating an example of the configuration of the controller illustrated in FIG. [Figure 4] FIG. 4 is a diagram illustrating an example of the configuration of the D-type flip-flop illustrated in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment will be described with reference to the drawings. Throughout the embodiments described below, the same components are denoted by the same reference numerals, and repeated description will be omitted. Note that the drawings are schematic or conceptual.

[0009] Fig. 1 illustrates a schematic diagram of a condition monitoring system 100 according to an embodiment. As illustrated in Fig. 1, the condition monitoring system 100 includes a vibration power generator 102 and a condition monitoring device 110 as a sensor device. The vibration power generator 102 is connected to the condition monitoring device 110 and supplies power to the condition monitoring device 110. The condition monitoring device 110 operates on the power supplied by the vibration power generator 102.

[0010] The vibration generator 102 converts environmental vibration energy into electrical energy. Specifically, the vibration generator 102 converts mechanical energy due to mechanical vibrations caused by environmental vibrations into AC power. The AC power can be single-phase AC power. In one structural example, the vibration generator 102 includes a movable part and a stationary part that movably supports the movable part. The movable part includes a coil, and the stationary part includes a magnet disposed inside the coil. The relationship between the coil and the magnet may be reversed. Specifically, the movable part may be provided with a magnet, and the stationary part may be provided with a coil. When vibration is applied to the vibration generator 102, the movable part vibrates. As a result, the magnet and the coil move relative to each other, and the magnetic flux interlinked with the coil changes over time. As a result, an electromotive force is generated by electromagnetic induction. In this way, the vibration applied to the vibration generator 102 is converted into AC power. The vibration generator 102 is an example of a generator that generates AC power.

[0011] The condition monitoring device 110 monitors the condition of an object. The condition monitoring device 110 includes a rectifying and smoothing circuit 114, a converter 116, a power storage circuit 118, a control circuit 120, and a sensor 130.

[0012] The sensor 130 is used to monitor the condition of an object. In an example in which the condition monitoring device 110 monitors the crack condition of a structure, the sensor 130 may be an acoustic emission (AE) sensor that detects AE waves. AE waves are sound waves emitted from inside a solid material when the solid material is deformed or destroyed. The condition monitoring device 110 detects the occurrence of a crack in the structure by measuring the AE waves with the sensor 130.

[0013] The rectifying and smoothing circuit 114 is connected to the vibration generator 102 and converts the AC power output from the vibration generator 102 into DC power. As an example, the rectifying and smoothing circuit 114 includes a rectifying circuit and a smoothing circuit. The rectifying circuit converts the AC power output from the vibration generator 102 into DC power. In an example where the generator is the vibration generator 102, the DC power output from the rectifying circuit is usually pulsating. The rectifying circuit includes, for example, one or more diodes. For example, the rectifying circuit may be a full-wave rectifier in which four diodes are bridge-connected. The smoothing circuit smoothes the DC power output from the rectifying circuit. The smoothing circuit includes, for example, one capacitor. The smoothing circuit may also include multiple capacitors. The smoothing circuit may also include a combination of a capacitor and an inductor. The smoothing circuit temporarily stores the current as an electric charge and smoothes the voltage by releasing the stored electric charge. In other words, the smoothing circuit is a kind of storage circuit that stores power.

[0014] The converter 116 is connected to the rectifying and smoothing circuit 114, and transforms the voltage output from the rectifying and smoothing circuit 114. As an example, the converter 116 is a DC / DC converter such as a buck-boost converter.

[0015] The storage circuit 118 is connected to the converter 116 and temporarily stores the voltage output from the converter 116. The storage circuit 118 may include one or more capacitors. The storage circuit 118 may also include a combination of a capacitor and a coil.

[0016] The converter 116 and the storage circuit 118 are connected to the sensor 130 , and the sum of the output voltage of the converter 116 and the output voltage of the storage circuit 118 is applied to the sensor 130 .

[0017] The sensor 130 operates with power supplied by the vibration power generator 102 via an electric circuit including a rectifier / smoothing circuit 114 , a converter 116 , and a power storage circuit 118 .

[0018] The control circuit 120 controls the operation mode of the sensor 130 based on the power output from the vibration power generator 102. The operation modes include an active mode and a sleep mode. The active mode is a mode in which the sensor 130 performs a predetermined measurement operation. The sleep mode is a mode in which the sensor 130 stops operating. The control circuit 120 includes a first comparator 122, a second comparator 124, and a controller 126.

[0019] The first comparator 122 is connected to the rectifying and smoothing circuit 114. The first comparator 122 generates a first trigger signal based on the rectified and smoothed voltage (the voltage output from the rectifying and smoothing circuit 114) and outputs the first trigger signal to the controller 126. The first comparator 122 is also called a first generating unit.

[0020] The first comparator 122 may have a hysteresis characteristic. Specifically, the first comparator 122 may be configured to compare the rectified and smoothed voltage with a first reference voltage and a second reference voltage, and to output a High to the controller 126 when the rectified and smoothed voltage becomes equal to or greater than the first reference voltage, and to output a Low to the controller 126 when the rectified and smoothed voltage becomes equal to or less than the second reference voltage. The second reference voltage is lower than the first reference voltage.

[0021] The first comparator 122 may be configured to compare the rectified and smoothed voltage with a single reference voltage, and output a High to the controller 126 when the rectified and smoothed voltage is equal to or greater than the reference voltage, and output a Low to the controller 126 when the rectified and smoothed voltage is less than the reference voltage. However, in order to ensure stable operation of the sensor 130, it is desirable for the first comparator 122 to be a comparator circuit having a hysteresis characteristic.

[0022] The second comparator 124 is connected to the converter 116. The second comparator 124 generates a second trigger signal based on the converter output voltage (the voltage output from the converter 116) and outputs the second trigger signal to the controller 126. The second comparator 124 is also called a second generating unit.

[0023] The second comparator 124 may have a hysteresis characteristic. Specifically, the second comparator 124 may be configured to compare the converter output voltage with a third reference voltage and a fourth reference voltage, and to output a High signal to the controller 126 when the converter output voltage becomes equal to or greater than the third reference voltage, and to output a Low signal to the controller 126 when the converter output voltage becomes equal to or less than the fourth reference voltage. The fourth reference voltage is lower than the third reference voltage.

[0024] The third reference voltage is set to a value equal to or less than the allowable voltage of the sensor 130. The allowable voltage of the sensor 130 refers to the upper limit of the voltage that can be applied to the sensor 130. By setting the third reference voltage to a value equal to or less than the allowable voltage, a voltage exceeding the allowable voltage is prevented from being applied to the sensor 130. The fourth reference voltage is set to a value equal to or more than the drive voltage of the sensor 130. The drive voltage of the sensor 130 refers to the lower limit of the voltage required for the sensor 130 to operate. By setting the fourth reference voltage to a value equal to or more than the drive voltage, the voltage applied to the sensor 130 when the sensor 130 is in the active mode is prevented from falling below the drive voltage.

[0025] The second comparator 124 may be configured to compare the converter output voltage with a single reference voltage, and output a High to the controller 126 when the converter output voltage is equal to or greater than the reference voltage, and output a Low to the controller 126 when the converter output voltage is less than the reference voltage. However, in order to ensure stable operation of the sensor 130, it is desirable for the second comparator 124 to be a comparator circuit having a hysteresis characteristic.

[0026] The controller 126 is connected to the first comparator 122 and the second comparator 124. The controller 126 switches the operation mode of the sensor 130 between an active mode and a sleep mode based on a first trigger signal output from the first comparator 122 and a second trigger signal output from the second comparator 124.

[0027] The controller 126 generates a wake-up signal based on the first trigger signal and the second trigger signal, and outputs the wake-up signal to the sensor 130. The wake-up signal is a control signal that controls the operation mode of the sensor 130. For example, when the wake-up signal is in a low state, the sensor 130 is in a sleep mode, and when the wake-up signal is in a high state, the sensor 130 is in an active mode.

[0028] The controller 126 sets the wake-up signal to High when the first trigger signal switches to High while the second trigger signal is High. When the wake-up signal switches to High, the sensor 130 transitions to an active mode and performs a predetermined measurement operation. When at least one of the first trigger signal and the second trigger signal becomes Low, the controller 126 sets the wake-up signal to Low. When the wake-up signal switches to Low, the sensor 130 transitions to a sleep mode.

[0029] Next, an example of the operation of the control circuit 120 will be described with reference to FIG.

[0030] 2 shows the environmental acceleration, the rectified and smoothed voltage, the converter output voltage, the first trigger signal, the second trigger signal, and the wake-up signal, which change over time. The environmental acceleration is the acceleration of the environmental vibration applied to the vibration power generator 102.

[0031] As shown in FIG. 2, initially, the first trigger signal, the second trigger signal, and the wake-up signal are all at a low signal level. The rectified and smoothed voltage changes according to the environmental acceleration. Electric power is generated by the vibration power generator 102 based on the environmental vibration. This causes the power to be gradually stored in the storage circuit 118, i.e., the converter output voltage gradually increases. Then, the converter output voltage increases relative to the third reference voltage V R3 When the voltage reaches the first reference voltage V, the second trigger signal switches to high. R1When the second trigger signal reaches the first trigger signal, the first trigger signal switches to High. When the first trigger signal switches to High while the second trigger signal is High, the wake-up signal switches to High. As a result, the sensor 130 wakes up and performs a predetermined measurement operation.

[0032] The environmental vibration becomes smaller, so that the rectified and smoothed voltage becomes equal to the second reference voltage V R2 Below this, the first trigger signal switches low.

[0033] As the sensor 130 operates, the stored power is consumed. Therefore, the converter output voltage gradually decreases. Then, when the converter output voltage reaches the fourth reference voltage V R4 Below this, the second trigger signal switches low, which causes the wake-up signal to switch low, causing the sensor 130 to sleep.

[0034] In addition, the wake-up signal may be switched to Low when the first trigger signal is switched to Low. In other words, when the rectified and smoothed voltage is lower than the second reference voltage V R2 The wake-up signal may be switched low when:

[0035] The converter output voltage is the third reference voltage V R3 When the rectified and smoothed voltage is equal to or lower than the first reference voltage V R1 , the wake-up signal is maintained at Low. This makes it possible to maintain the converter output voltage at or above the drive voltage of the sensor 130.

[0036] The above-mentioned algorithm may be implemented in software or hardware. For example, a processor (circuit) such as a microprocessor may execute a software program to execute the processes described with respect to the controller 126. An example in which the controller 126 is realized by an electric circuit, which is hardware, will be described with reference to Figs. 3 and 4.

[0037] Fig. 3 shows an example of an electric circuit that realizes the controller 126. In the example shown in Fig. 3, the controller 126 includes a delay (D) flip-flop circuit 302, a NOT circuit 304, an AND circuit 306, input terminals 312 and 314, and an output terminal 316.

[0038] A general D-type flip-flop circuit can be used as the D-type flip-flop circuit 302. For example, a D-type flip-flop circuit in which six 3-input NAND gates 402, 404, 406, 408, 410, and 412 shown in FIG. 4 are combined can be used.

[0039] 3, the input terminal 312 is connected to the first comparator 122 shown in FIG. 1, the input terminal 314 is connected to the second comparator 124 shown in FIG. 1, and the output terminal 316 is connected to the sensor 130 shown in FIG. 1. The input terminal 312 is connected to a CLK (clock) terminal of a D-type flip-flop circuit 302. The input terminal 314 is connected to a D (delay) terminal of the D-type flip-flop circuit 302, an input terminal of a NOT circuit 304, and a first input terminal of an AND circuit 306. The output terminal of the NOT circuit 304 is connected to a CLR (clear) terminal of the D-type flip-flop circuit 302. The Q terminal of the D-type flip-flop circuit 302 is connected to a second input terminal of the AND circuit 306. The output terminal of the AND circuit 306 is connected to the output terminal 316.

[0040] The first trigger signal is input to a CLK terminal of a D-type flip-flop circuit 302, the second trigger signal is input to a D terminal of the D-type flip-flop circuit 302, and a NOT operation output of the second trigger signal is input to a D terminal of the D-type flip-flop circuit 302. The first trigger signal and the Q output of the D-type flip-flop circuit 302 are input to an AND circuit 306. The AND circuit 306 generates an AND operation output of the first trigger signal and the Q output. This AND operation output becomes a wake-up signal.

[0041] 3 is an example of the configuration of the controller 126, and the controller may have other configurations. For example, the controller 126 may be configured with a trigger signal detection circuit and a flip-flop circuit.

[0042] As described above, the control circuit 120 controls the operation mode of the sensor 130 based on the power output from the vibration power generator 102. Specifically, the control circuit 120 is configured to generate a first trigger signal based on the output voltage of the rectifier / smoothing circuit 114, generate a second trigger signal based on the output voltage of the converter 116, and switch the operation mode of the sensor 130 between a sleep mode and an active mode based on the first trigger signal and the second trigger signal. Therefore, the state monitoring device 110 does not need another sensor (e.g., an acceleration sensor) to be used to wake up the sensor 130. This makes it possible to reduce power consumption in the state monitoring device 110.

[0043] For example, the condition monitoring device 110 uses the sensor 130 to monitor the crack condition of the object. When the object vibrates greatly, a large AE wave is output. When the object vibrates greatly, the control circuit 120 wakes up the sensor 130. Specifically, when the object vibrates greatly, the rectified and smoothed voltage becomes large. This causes the first comparator 122 to output a first trigger signal with a high signal level. The controller 126 wakes up the sensor 130 in response to the first trigger signal with a high signal level. In this way, the sensor 130 can be activated when a large AE wave is output. The condition monitoring device 110 can monitor the crack condition of the object without other sensors such as an acceleration sensor.

[0044] In the embodiments described above, the vibration power generator 102 is shown as a separate device from the condition monitoring device 110. Alternatively, the condition monitoring device 110 may comprise the vibration power generator 102.

[0045] At least one of the rectifying and smoothing circuit 114, the converter 116, the storage circuit 118, and the control circuit 120 may be provided outside the condition monitoring device 110. In one example, the control circuit 120 may be realized as a separate control device. The control device may be incorporated into the condition monitoring device 110 when the condition monitoring device 110 is manufactured. In another example, the vibration power generator 102, the rectifying and smoothing circuit 114, the converter 116, the storage circuit 118, and the control circuit 120 may be realized as separate power supply devices. The condition monitoring device 110 may be formed by connecting the power supply device to the sensor 130. The power supply device may be built into the condition monitoring device 110. The condition monitoring device 110 may be operated by a combination of power supplied from the power supply device and power supplied from another power source.

[0046] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0047] 100...condition monitoring system, 102...vibration power generator, 110...condition monitoring device, 114...rectifier / smoothing circuit, 116...converter, 118...storage circuit, 120...control circuit, 122...first comparator, 124...second comparator, 126...controller, 130...sensor, 302...D-type flip-flop circuit, 304...NOT circuit, 306...AND circuit, 312, 314...input terminal, 316...output terminal, 402, 404, 406, 408, 410, 412...NAND gates.

Claims

1. A control device for controlling an operation mode of a sensor that operates with power supplied from a generator via an electric circuit including a rectifying and smoothing circuit that converts AC power output from the generator into DC power and a converter that transforms an output voltage of the rectifying and smoothing circuit, a first generating unit that generates a first trigger signal based on the output voltage of the rectifying and smoothing circuit; a second generating unit configured to generate a second trigger signal based on an output voltage of the converter; a controller that is determined based on the first trigger signal and the second trigger signal, and that outputs a signal including information regarding an operation mode of the sensor to the sensor, thereby switching the operation mode of the sensor between a sleep mode in which the sensor stops operating and a state in which charge can be accumulated in a capacitor included in the rectifying and smoothing circuit, and an active mode in which the sensor can perform measurement and accumulate charge in the capacitor; Equipped with A control device, wherein switching an operational mode of the sensor between the sleep mode and the active mode includes switching an operational mode of the sensor from the active mode to the sleep mode.

2. the first generating unit outputs the first trigger signal at a first signal level in response to the output voltage of the rectifying and smoothing circuit becoming equal to or higher than a first reference voltage, and outputs the first trigger signal at a second signal level different from the first signal level in response to the output voltage of the rectifying and smoothing circuit becoming equal to or lower than a second reference voltage that is equal to or lower than the first reference voltage. The control device according to claim 1 .

3. the second generating unit outputs the second trigger signal at a third signal level in response to the output voltage of the converter becoming equal to or higher than a third reference voltage, and outputs the second trigger signal at a fourth signal level different from the third signal level in response to the output voltage of the converter becoming equal to or lower than a fourth reference voltage that is equal to or lower than the third reference voltage. The control device according to claim 1 or 2.

4. the first generating unit outputs the first trigger signal at a first signal level in response to the output voltage of the rectifying and smoothing circuit becoming equal to or higher than a first reference voltage, and outputs the first trigger signal at a second signal level different from the first signal level in response to the output voltage of the rectifying and smoothing circuit becoming equal to or lower than a second reference voltage that is equal to or lower than the first reference voltage; the second generating unit outputs the second trigger signal at a third signal level in response to the output voltage of the converter becoming equal to or higher than a third reference voltage, and outputs the second trigger signal at a fourth signal level different from the third signal level in response to the output voltage of the converter becoming equal to or lower than a fourth reference voltage that is equal to or lower than the third reference voltage; The controller: when the first trigger signal switches to the first signal level while the second trigger signal is at the third signal level, switching the operation mode of the sensor based on the signal; when the first trigger signal switches to the second signal level or when the second trigger signal switches to the fourth signal level, switching the operation mode of the sensor based on the signal; The control device according to claim 1 .

5. the controller switches an operation mode of the sensor from the sleep mode to the active mode when the first trigger signal switches from the second signal level to the first signal level while the second trigger signal is at the third signal level. The control device according to claim 4.

6. the controller switches the operation mode of the sensor based on the signal when the second trigger signal switches to the fourth signal level while the first trigger signal is at the second signal level; The control device according to claim 4 or 5.

7. the controller comprises a flip-flop circuit; A control device according to any one of claims 1 to 6.

8. The flip-flop circuit is a delay type flip-flop circuit consisting of six NAND gates. The control device according to claim 7.

9. A control device according to any one of claims 1 to 8; The sensor; The electrical circuit; A condition monitoring device comprising:

10. a storage circuit capable of storing the power output from the electric circuit, the converter is electrically connected between the rectifying and smoothing circuit and the storage circuit; The condition monitoring device according to claim 9.

11. The condition monitoring device according to claim 9 or 10, further comprising the generator.

12. The sensor is an acoustic emission (AE) sensor that measures AE waves. The condition monitoring device according to any one of claims 9 to 11.

13. A control device for controlling an operation mode of a sensor that operates on power supplied from a generator via an electric circuit having a rectifying and smoothing circuit that converts AC power output from the generator into DC power and a converter that transforms an output voltage of the rectifying and smoothing circuit, comprising: a first generating unit that generates a first trigger signal based on the output voltage of the rectifying and smoothing circuit; a second generating unit configured to generate a second trigger signal based on an output voltage of the converter; a controller that is determined based on the first trigger signal and the second trigger signal, and that outputs a signal including information regarding an operation mode of the sensor to the sensor, thereby switching the operation mode of the sensor between a sleep mode in which the sensor stops operating and a state in which charge can be accumulated in a capacitor included in the rectifying and smoothing circuit, and an active mode in which the sensor can perform measurement and accumulate charge in the capacitor; Equipped with the first generating unit outputs the first trigger signal at a first signal level in response to the output voltage of the rectifying and smoothing circuit becoming equal to or higher than a first reference voltage, and outputs the first trigger signal at a second signal level different from the first signal level in response to the output voltage of the rectifying and smoothing circuit becoming equal to or lower than a second reference voltage that is equal to or lower than the first reference voltage; the second generating unit outputs the second trigger signal at a third signal level in response to the output voltage of the converter becoming equal to or higher than a third reference voltage, and outputs the second trigger signal at a fourth signal level different from the third signal level in response to the output voltage of the converter becoming equal to or lower than a fourth reference voltage that is equal to or lower than the third reference voltage; The controller: when the first trigger signal switches to the first signal level while the second trigger signal is at the third signal level, switching the operation mode of the sensor based on the signal; when the second trigger signal switches to the fourth signal level while the first trigger signal is at the second signal level, switching the operation mode of the sensor based on the signal; Control device.

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