JP2023013335A - Power generation control device - Google Patents

Abstract

To provide a power generation control device capable of obtaining power generation characteristics capable of efficiently generating power while stably supplying power.SOLUTION: A power generation control device 1 controls driving of a power generation device which generates power by using sound waves having a natural frequency. The power generation control device 1 includes: a power generation characteristic change detecting portion 11 for detecting whether or not the power generation characteristic of the power generation device S has changed; and a power generation characteristic acquisition portion 12 for acquiring a power generation characteristic of the power generation device S when the power generation characteristic change detection portion 11 detects that the power generation characteristic of the power generation device S has changed.SELECTED DRAWING: Figure 1

Description

The present invention relates to a power generation control device that controls driving of a power generation device.

A power generation control device that controls driving of a power generation device is known. As such a power generation control device, for example, Patent Document 1 discloses a power generation control device that changes the load based on the result of comparing the power before changing the load and the power after changing the load. It is

The power generation control device has a load changing section, a power comparing section, and a load determining section. The load changer changes the load associated with the power generated by the generator. The power comparison unit compares power before the load is changed by the load changer and power after the load is changed by the load changer. The load determination unit determines whether or not to cause the load change unit to change the load based on the result of comparison by the power comparison unit.

The power generation control device automatically changes the load associated with the power generated by the wind power generator while the wind power generator is in operation, and detects the control characteristics of the wind power generator with which high power can be obtained. As a result, high power can be extracted according to the characteristic curve indicating the control characteristics detected by the power generation control device during operation without designing a power generation control device dedicated to each wind power generator.

JP 2016-19351 A

By the way, in the configuration disclosed in the above-mentioned Patent Document 1, the control characteristic of the wind power generator is detected by changing the load related to the electric power generated by the wind power generator. However, in such a configuration, the load associated with the power generated by the wind power generator is frequently changed, which may cause a problem of unstable power supply.

On the other hand, there is a demand for a power generation control device that can stably supply power and obtain power generation characteristics that enable efficient power generation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a power generation control device capable of stably supplying power and obtaining power generation characteristics that enable efficient power generation.

A power generation control device according to an embodiment of the present invention is a power generation control device that controls driving of a power generation device that generates power using an energy wave having a natural frequency. The power generation control device includes a power generation characteristic change detection unit that detects whether the power generation characteristics of the power generation device have changed, and when the power generation characteristic change detection unit detects that the power generation characteristics of the power generation device have changed includes a power generation characteristic acquisition unit that acquires the power generation characteristic of the power generation device (first configuration).

In this way, in the case of a power generator that generates power using an energy wave having a natural frequency, the power generation control device drives the generator or the like of the power generator in accordance with the natural frequency of the energy wave. Therefore, when the power generation device is driven to obtain power, the power generation control device grasps the power that can be output from the power generation device from the power generation characteristics of the power generation device that match the natural frequency of the energy wave. .

By the way, if the natural frequency of at least one of the device that generates the energy wave and the generator changes due to aging of the power generation device, the power generation characteristics of the power generation device will change. As a result, the power that can be output from the power generator also changes.

On the other hand, as in the above-described configuration, when the power generation characteristics of the power generation device change, the power generation control device obtains the power generation characteristics of the power generation device, thereby preventing the power generation from changing over time as described above. Even if the power generation characteristics of the power generation device change due to the change in the natural frequency of the device that constitutes the device, the power generation characteristics of the power generation device after the change can be grasped and the drive of the power generation device can be controlled. .

Moreover, when the power generation characteristics change detection unit detects that the power generation characteristics of the power generation device have changed, the power generation characteristics acquisition unit acquires the power generation characteristics of the power generation device. There is no need to frequently change the power generation characteristics of

Therefore, it is possible to obtain a power generation control device that can stably supply power and obtain power generation characteristics that enable efficient power generation.

A said 1st structure WHEREIN: The said electric power generating apparatus has a linear generator which generates electric power using the vibration produced by the said energy wave. The power generation characteristic change detection unit detects that the power generation characteristic of the power generation device has changed based on the vibration frequency and the reference vibration frequency when the linear generator is operating (second configuration).

Accordingly, when the power generation device has a linear generator, the power generation characteristic change detection unit detects changes in the power generation characteristics of the power generation device based on the vibration frequency and the reference vibration frequency when the linear power generator is operating. can be detected. Therefore, the power generation control device can easily detect changes in the power generation characteristics of the power generation device.

In the second configuration, when the difference between the vibration frequency and the reference vibration frequency when the linear generator is operating exceeds a threshold, the power generation characteristic change detection unit detects the power generation of the power generation device. Detect when a property has changed. The threshold is determined based on the reference vibration frequency and a drive stop frequency for stopping the drive of the linear generator (third configuration).

Thus, even if the vibration frequency of the linear generator is different from the reference vibration frequency, the power generation characteristic change detector does not detect the change in the power generation characteristic of the power generator until the difference between them exceeds the threshold value. Therefore, it is possible to prevent the power generation control device from frequently acquiring the power generation characteristics of the power generation device due to changes in the vibration frequency of the linear power generator.

Moreover, the threshold value is determined based on the reference vibration frequency and the drive stop frequency for stopping the drive of the linear generator. Therefore, the threshold value can be determined within a range in which the driving of the linear generator does not stop, and in consideration of disturbances and the like.

Therefore, the power generation control device prevents the power generation control device from frequently acquiring the power generation characteristics of the power generation device within a range in which the drive of the linear generator is not stopped, and also considers disturbances, etc., and determines the power generation characteristics of the power generation device. can be obtained.

In the second or third configuration, when the power generation characteristics acquisition unit acquires the power generation characteristics of the power generation device, the reference vibration is set to the vibration frequency when the linear generator is driven. A frequency updating unit is further provided (fourth configuration).

Thereby, when the power generation characteristic of the power generation device changes and the power generation characteristic acquisition unit acquires the power generation characteristic after the change, the reference vibration frequency can be changed. Therefore, it is possible to change the criteria for acquiring the power generation characteristics in accordance with aging of the power generation device. Therefore, the power generation characteristics of the power generation device grasped by the power generation control device can be changed at appropriate timing.

In any one of the first to fourth configurations, the energy wave is a sound wave obtained by a thermoacoustic phenomenon (fifth configuration).

As a result, when the power generation characteristics of the power generation device that generates power using sound waves change, the power generation control device can grasp the power generation characteristics of the power generation device after the change and control the driving of the power generation device. can.

According to the power generation control device according to one embodiment of the present invention, the power generation characteristic change detection section that detects a change in the power generation characteristic of the power generation device, and the power generation characteristic change detection section detect that the power generation characteristic of the power generation device has changed. and a power generation characteristic acquisition unit that acquires the power generation characteristic of the power generation device when the power generation characteristic is detected. As a result, it is possible to obtain a power generation control device capable of stably supplying power and obtaining power generation characteristics that enable efficient power generation.

FIG. 1 is a block diagram showing a schematic configuration of a power generator including a power generation control device according to an embodiment. FIG. 2 is a circuit diagram showing a schematic configuration of the power converter. FIG. 3 is a diagram showing an example of how the relationship between the moving speed of the mover of the linear generator and the generated power changes with temperature. FIG. 4 is a diagram showing an example of the relationship between the moving speed of the mover of the linear generator and the generated power at a predetermined temperature. FIG. 5 is a diagram schematically showing a method of obtaining the maximum power point. FIG. 6 is a diagram schematically showing a method of obtaining a power generation characteristic curve. FIG. 7 is a flow chart showing the operation of the power generation control device to acquire the power generation characteristics of the linear generator.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The same reference numerals are given to the same or corresponding parts in the drawings, and the description thereof will not be repeated.

(power generator)
FIG. 1 is a block diagram showing a schematic configuration of a power generator S including a power generation control device 1 according to an embodiment of the present invention. This generator S obtains electric power by driving a linear generator with vibrations obtained by using thermoacoustic phenomena. Specifically, the power generator S includes a power generation control device 1 , a sound wave converter 2 , a vibration converter 3 , a linear generator 4 and a power converter 5 .

The sound wave converter 2 generates sound waves using the thermoacoustic phenomenon. In the thermoacoustic phenomenon, one of the tubes is heated to a predetermined temperature or higher and the other is cooled, so that the gas in the tube becomes unstable and starts to vibrate, and this vibration acts as a substitute for the piston. It is generated by the energy conversion of heat and work. The principle of generating sound waves using the thermoacoustic phenomenon is the same as the principle of a generally known thermoacoustic engine, so detailed description will be omitted.

The sound wave converter 2 is a device that converts thermal energy into acoustic energy. Although not shown, the sound wave converter 2 includes a plurality of thin tubes, a heating section that heats the plurality of thin tubes, and a cooling section that cools the plurality of thin tubes. The configuration of the sound wave conversion unit 2 is the same as the conventional configuration capable of realizing the thermoacoustic phenomenon. Therefore, detailed description of the configuration of the sound wave conversion unit 2 is omitted.

The vibration converter 3 generates vibration from the sound waves generated by the sound wave converter 2 . The vibration converting section 3 has a vibration driving section (not shown) that vibrates by the sound wave. The vibration drive section vibrates by reciprocating upon receiving the acoustic energy.

The linear power generator 4 utilizes the vibration generated by the vibration converter 3 to generate power. Although not shown, the linear generator 4 has, for example, a mover having magnets and a cylindrical stator having coils. The mover is positioned within the cylindrical stator and reciprocates in the axial direction within the stator by the vibration. As a result, the magnetic field generated by the magnet of the mover moves with respect to the coil of the stator, so that an induced current flows through the coil and the linear generator 4 outputs electric power.

The power conversion unit 5 converts the AC power generated by the linear generator 4 into predetermined power, and outputs the power to the power system. Specifically, the power converter 5 converts the AC power output from the linear generator 4 into DC power, and then converts the DC power into predetermined AC power.

FIG. 2 is a circuit diagram showing a schematic configuration of the power converter 5. As shown in FIG. As shown in FIG. 2 , power converter 5 includes DC converter 51 , smoothing capacitor 52 , and AC converter 53 . The DC converter 51 converts AC power output from the linear generator 4 into DC power. Smoothing capacitor 52 smoothes the DC power output from DC converter 51 . The AC converter 53 converts the DC power output from the DC converter 51 into AC power. The DC converter 51 and AC converter 53 each have a plurality of switching elements SW.

In this embodiment, the DC converter 51 has, for example, four switching elements SW that constitute a single-phase bridge circuit. The AC converter 53 has, for example, six switching elements SW that form a three-phase bridge circuit.

In response to a request from the power system, the AC converter 53 converts the DC power output from the DC converter 51 into AC power having the requested frequency and power, and outputs the AC power.

(Generation control device)
Next, the configuration of the power generation control device 1 will be described below.

The power generation control device 1 controls driving of the power conversion unit 5 . Specifically, the power generation control device 1 controls driving of the DC converter 51 and the AC converter 53 of the power converter 5 in response to a request from the power system.

By the way, the characteristics of at least part of the sound wave converter 2, the vibration converter 3, and the linear generator 4 in the power generator S change over time. Therefore, the power generation characteristics of the power generation device S may change gradually.

FIG. 3 is a diagram showing an example of how the relationship between the moving speed of the mover of the linear generator 4 and the generated power changes with temperature. As shown in FIG. 3 , the power generated by the linear generator 4 changes according to the moving speed of the mover of the linear generator 4 . At each temperature, there is a moving speed of the mover of the linear generator 4 that maximizes the power generated by the linear generator 4 . By connecting such maximum power points, a power generation characteristic curve of the linear generator 4 as shown in FIG. 3 is obtained.

FIG. 4 is a diagram showing an example of the relationship between the moving speed of the mover of the linear generator 4 and the generated power at a predetermined temperature. At the initial stage of operation of the power generator S, the power generation characteristic curve of the linear power generator 4 is an initial power generation characteristic curve as indicated by the solid line. When the relationship between the moving speed of the mover of the linear generator 4 and the generated power at the predetermined temperature changes as shown by the dashed line due to aging of the power generator S, the generator characteristic curve of the linear generator 4 also changes to the dashed line. After the change as shown, the power generation characteristic curve changes.

As shown in FIG. 4, when the movable element of the linear generator 4 has a speed of V1, the linear generator 4 can generate power up to P1 at the initial stage of operation of the power generation device S. When the power generation characteristic curve changes, the linear power generator 4 can generate power only up to power P2. That is, the power generation capacity of the linear power generator 4 is degraded due to aging of the power generation device S or the like.

The power generation control device 1 assumes that the linear generator 4 can output the power of the initial power generation characteristic curve shown in FIG. If the generated power of 4 is converted into power, there is a possibility that an excessive load will be applied to the linear generator 4 .

On the other hand, the power generation control device 1 of the present embodiment also has a function of grasping the power generation characteristics of the power generation device S, including changes in the power generation characteristic curve of the linear generator 4 as described above. Specifically, the power generation control device 1 detects changes in the power generation characteristics of the power generation device S, and acquires the power generation characteristics when the power generation characteristics have changed by a predetermined amount or more. In addition, when acquiring new power generation characteristics, the power generation control device 1 updates the reference vibration frequency used when determining whether the power generation characteristics have changed.

Specifically, the power generation control device 1 includes a power generation characteristic change detection unit 11 , a power generation characteristic acquisition unit 12 , and a reference vibration frequency update unit 13 .

The power generation characteristic change detection unit 11 detects a change in the power generation characteristic of the power generation device S. FIG. The power generation characteristic change detection unit 11 detects a change in the power generation characteristic by comparing the vibration frequency of the linear generator 4 with a reference vibration frequency. Specifically, the power generation characteristic change detection unit 11 detects that the power generation characteristic of the power generation device S has changed when the difference between the vibration frequency and the reference vibration frequency is greater than a frequency threshold (threshold value). That is, the power generation characteristic change detection unit 11 detects that the power generation characteristic of the power generation device S has changed when the following expression is satisfied.
Δfth<Δf=f−fr

Here, Δfth is the frequency threshold, and Δf is the difference between the vibration frequency f of the linear generator 4 and the reference vibration frequency fr.

The frequency threshold Δfth is determined based on the reference vibration frequency fr and the drive stop frequency fc at which the drive of the linear generator 4 stops. Specifically, the lower limit of the frequency threshold Δfth is determined by considering the range f1, which is susceptible to detection errors, disturbances, and the like, with respect to the reference vibration frequency fr. Further, the upper limit value of the frequency threshold Δfth is determined by taking into account the range f2 in which the drive of the linear generator 4 may stop due to a detection error, disturbance, or the like with respect to the driving stop frequency fc of the linear generator 4. be. The frequency threshold Δfth is set, for example, so as to satisfy the following relationship.
(fr+f1)<(Δf+fr)<(fc−f2)

Here, the reference vibration frequency fr is set to the vibration frequency of the linear generator 4 when the initial power generation characteristic curve is acquired. The vibration frequency is a theoretical value including a design value or the like, or a measured value including the vibration frequency or the like when adjusting the acoustic impedance when the power generation device S is installed.

The power generation characteristic acquisition unit 12 reacquires the power generation characteristics of the power generation device S when the power generation characteristic change detection unit 11 detects that the power generation characteristics of the power generation device S have changed. Specifically, the power generation characteristic acquisition unit 12 reacquires the power generation characteristic curve of the linear generator 4 when the power generation characteristic change detection unit 11 detects that the power generation characteristic of the power generation device S has changed. Reacquisition of the power generation characteristic curve by the power generation characteristic acquisition unit 12 is performed, for example, as follows.

FIG. 5 is a diagram schematically showing a method of obtaining the maximum power point. The power generation characteristic acquisition unit 12 changes the output current of the linear generator 4 within a range R as shown in FIG. Find the maximum power point PA. At this time, the power generation characteristic acquisition unit 12 detects, for example, the current input to the DC conversion unit 51 of the power conversion unit 5 as the output current, and increases or decreases the output current of the linear generator 4 by the hill-climbing method.

When detecting the maximum power point PA, the power generation characteristic acquisition unit 12 obtains the maximum power point PA using a moving average or obtains the maximum power point PA multiple times so as not to be affected by instantaneous fluctuations due to detection errors or disturbances. The maximum power point PA may be obtained using the detection result of .

The method of detecting the maximum power point PA of the linear generator 4 by the power generation characteristic acquisition unit 12 may be a method other than the above.

FIG. 6 is a diagram schematically showing a method of obtaining a power generation characteristic curve. The power generation characteristic acquisition unit 12 obtains a new power generation characteristic curve (broken line in FIG. 6) from the known power generation characteristic curve (solid line in FIG. 6) using the maximum power point PA detected as described above. . For example, when the moving speed of the mover of the linear generator 4 is B, the power generation characteristic acquisition unit 12 calculates the ratio between the power P obtained from the known power generation characteristic curve and the maximum power point PA detected as described above. may be used to obtain a proportionality constant, and a new power generation characteristic curve may be obtained by correcting the known power generation characteristic curve with this proportionality constant.

Note that the power generation characteristic acquisition unit 12 may obtain a new power generation characteristic curve by obtaining the maximum power point in a plurality of operating states of the linear generator 4 .

The reference vibration frequency update unit 13 updates the reference vibration frequency when the power generation characteristic change detection unit 11 detects a change in the power generation characteristic of the power generation device S. As a result, when the power generation characteristics of the power generation device S change, it is possible to change the reference for detecting the change in the power generation characteristics of the power generation device S thereafter. Therefore, the power generation characteristics of the power generation device S can be changed according to aging of the power generation device S or the like.

(How to acquire power generation characteristics)
Next, the operation of acquiring the power generation characteristics of the linear generator 4 by the power generation control device 1 having the above configuration will be described with reference to FIG. FIG. 7 is a flow chart showing the operation of the power generation control device 1 acquiring the power generation characteristics of the linear generator 4 .

When the flow shown in FIG. 7 starts (START), first, in step S1, the power generation control device 1 drives and controls the power generation device S according to the power required from the power system. At this time, the power generation control device 1 drives the power generation device S so that the power generated by the power generation device S becomes an optimum value according to the power generation characteristic curve stored in the storage unit (not shown).

In subsequent step S<b>2 , the power generation characteristic change detection unit 11 of the power generation control device 1 acquires the vibration frequency of the linear generator 4 . The power generation characteristic change detection unit 11 measures the vibration frequency using a position sensor or the like (not shown) provided in the linear power generator 4 . In step S3, the power generation characteristic change detection unit 11 determines whether the difference Δf between the vibration frequency f of the linear generator 4 and the reference vibration frequency fr is greater than a frequency threshold (threshold) Δfth.

In step S3, when the power generation characteristic change detection unit 11 determines that Δf>Δfth (if YES), the process proceeds to step S4, where the power generation characteristic acquisition unit 12 acquires the power generation characteristic curve of the linear generator 4. do. On the other hand, if the power generation characteristic change detection unit 11 determines that Δf>Δfth in step S3 (NO), the process returns to step S2 to acquire the vibration frequency of the linear generator 4 again.

In step S4, after detecting the maximum power point, the power generation characteristic acquiring unit 12 obtains a new power generation characteristic curve using the maximum power point for the known power generation characteristic curve. After that, in step S5, the reference vibration frequency update unit 13 updates the vibration frequency f of the linear generator 4 to a new reference vibration frequency fr.

After that, this flow ends (END).

As described above, the power generation control device 1 of the present embodiment controls driving of a power generation device that generates power using sound waves having a natural frequency. The power generation control device 1 includes a power generation characteristic change detection unit 11 that detects whether or not the power generation characteristics of the power generation device S have changed, and when the power generation characteristic change detection unit 11 detects that the power generation characteristics of the power generation device S have changed. includes a power generation characteristic acquiring unit 12 that acquires the power generation characteristic of the power generation device S.

Thus, in the case of a power generator that generates power using a sound wave having a natural frequency, the power generation control device drives the generator or the like of the power generator in accordance with the natural frequency of the sound wave. Therefore, when the power generation control device drives the power generation device to obtain power, the power generation control device grasps the power that can be output from the power generation device from the power generation characteristics of the power generation device S that match the natural frequency of the sound wave.

By the way, if the natural frequency of at least one of the sound wave conversion unit 2, the vibration conversion unit 3, and the linear generator 4 that generate sound waves changes in the power generation device S due to secular change of the power generation device S, the power generation device S will change. As the power generation characteristics change, the power that can be output from the power generation device S also changes.

On the other hand, as in the configuration described above, when the power generation characteristics of the power generation device S change, the power generation control device 1 acquires the power generation characteristics of the power generation device S, thereby causing To control the driving of a power generator S by grasping the power generation characteristics of the power generator S after the change, even when the natural frequency of the devices constituting the power generator S changes and the power generation characteristics of the power generator S change. can be done.

Moreover, when the power generation characteristic change detection unit 11 detects that the power generation characteristics of the power generation device S have changed, the power generation characteristic acquisition unit 12 acquires the power generation characteristics of the power generation device S. There is no need to frequently change the power generation characteristics of the device S.

Therefore, it is possible to obtain the power generation control device 1 that can stably supply power and obtain power generation characteristics that enable efficient power generation.

In this embodiment, the power generation device S has a linear power generator 4 that generates power using vibrations caused by the sound waves. The power generation characteristic change detection unit 11 detects that the power generation characteristic of the power generator S has changed based on the vibration frequency f and the reference vibration frequency fr when the linear generator 4 is operating.

Thereby, the power generation characteristic change detection unit 11 can detect a change in the power generation characteristic of the power generation device S based on the vibration frequency f and the reference vibration frequency fr when the linear generator 4 is operating. Therefore, the power generation control device 1 can easily detect changes in the power generation characteristics of the power generation device S. FIG.

In this embodiment, when the difference Δf between the vibration frequency f when the linear generator 4 is operating and the reference vibration frequency fr exceeds the frequency threshold Δfth, the power generation characteristic change detection unit 11 Detects changes in power generation characteristics. The frequency threshold Δfth is determined based on the reference vibration frequency fr and the drive stop frequency fc for stopping the driving of the linear generator 4 .

As a result, even if the vibration frequency of the linear generator 4 differs from the reference vibration frequency fr, the power generation characteristic change detection unit 11 detects the change in the power generation characteristic of the power generation device S until the difference exceeds the frequency threshold value Δfth. Not detected. Therefore, it is possible to prevent the power generation control device 1 from frequently acquiring the power generation characteristics of the power generation device S due to changes in the vibration frequency of the linear generator 4 .

Moreover, the frequency threshold Δfth is determined based on the reference vibration frequency fr and the drive stop frequency for stopping the driving of the linear generator 4 . Therefore, the frequency threshold value Δfth can be determined within a range in which the driving of the linear generator 4 does not stop, and in consideration of disturbances and the like.

Therefore, while preventing the power generation control device 1 from frequently acquiring the power generation characteristics of the power generation device S within a range in which the driving of the linear generator 4 is not stopped, the power generation characteristics of the power generation device S can be determined in consideration of disturbances and the like. can be obtained.

In the present embodiment, when the power generation characteristic acquisition unit 12 acquires the power generation characteristics of the power generation device S, the power generation control device 1 sets the vibration frequency f when the linear generator 4 is driving as the reference vibration frequency fr. A reference vibration frequency updating unit 13 is further provided.

Thereby, when the power generation characteristic of the power generation device S changes and the power generation characteristic acquisition unit 12 acquires the power generation characteristic after the change, the reference vibration frequency fr can be changed. Therefore, it is possible to change the criteria for obtaining the power generation characteristics in accordance with aging of the power generation device S or the like. Therefore, the power generation characteristics of the power generation device S grasped by the power generation control device 1 can be changed at appropriate timing.

(Other embodiments)
Although the embodiments of the present invention have been described above, the above-described embodiments are merely examples for carrying out the present invention. Therefore, without being limited to the above-described embodiment, it is possible to modify the above-described embodiment as appropriate without departing from the spirit thereof.

In the above embodiment, the power generator S generates power using sound waves obtained by thermoacoustic phenomena. However, the power generation device may generate power using an energy wave other than the sound wave caused by the thermoacoustic phenomenon as long as the energy wave has a natural frequency.

When the power generating device generates power using energy waves other than sound waves, the power generating device has another device for transmitting the energy waves to the power generator instead of the sound wave conversion unit and the vibration conversion unit. .

In said embodiment, the generator set S has a linear generator 4 . However, the power generator may have a generator other than the linear generator as long as it is a generator capable of generating power using an energy wave having a natural frequency.

In the above-described embodiment, the power generation characteristic change detection unit 11 of the power generation control device 1 uses changes in the vibration frequency of the linear generator 4 to detect changes in the power generation characteristics of the power generation device, including the power generation characteristics of the linear generator 4. do. However, the power generation characteristic change detection unit may detect the change in the power generation characteristic of the power generation device using the frequency of the sound wave obtained by the thermoacoustic phenomenon, the frequency of the current output from the linear generator, or the like. In addition, the power generation characteristic change detection unit compares the power obtained from the power generation characteristic curve with the power actually generated by the linear generator, and if the difference exceeds a threshold, the power generation characteristic of the power generator is changed. It may be detected that it has changed.

The power generation characteristic change detection unit detects the vibration frequency of the linear generator, the sound wave frequency, the frequency of the current output from the linear generator, and the difference between the power obtained from the power generation characteristic curve and the actual generated power. At least one of them may detect a change in the power generation characteristics of the power generation device.

In the above embodiment, the power generation control device 1 has the reference vibration frequency updating unit 13 . However, the power generation control device does not have to have the reference vibration frequency updating unit. That is, the power generation control device does not have to update the reference vibration frequency. For example, the difference between the initial power generation characteristics and the power generation characteristics after the change is small, so that the power generation characteristics of the power generation device are hardly affected even if the reference oscillation frequency is not updated, or the setting range of the frequency threshold Δfth is small. Therefore, if updating the reference vibration frequency may destabilize the power generation control of the power generation device, it is not necessary to update the reference vibration frequency as described above.

INDUSTRIAL APPLICABILITY The present invention can be used for a power generation control device that controls driving of a power generation device that generates power using energy waves having a natural frequency.

1 power generation control device 2 sound wave conversion unit 3 vibration conversion unit 4 linear generator 5 power conversion unit 11 power generation characteristic change detection unit 12 power generation characteristic acquisition unit 13 reference vibration frequency update unit 51 DC conversion unit 52 smoothing capacitor 53 AC conversion unit SW switching Element S generator

Claims (5)

A power generation control device that controls driving of a power generation device that generates power using an energy wave having a natural frequency,
a power generation characteristic change detection unit that detects whether the power generation characteristic of the power generation device has changed;
a power generation characteristic acquisition unit that acquires the power generation characteristics of the power generation device when the power generation characteristics change detection unit detects that the power generation characteristics of the power generation device have changed;
comprising
Power generation controller. In the power generation control device according to claim 1,
The power generation device has a linear power generator that generates power using vibrations caused by the energy waves,
The power generation characteristic change detection unit detects that the power generation characteristic of the power generation device has changed based on the vibration frequency and the reference vibration frequency when the linear generator is driven.
Power generation controller. In the power generation control device according to claim 2,
The power generation characteristic change detection unit detects that the power generation characteristic of the power generation device has changed when a difference between the vibration frequency and the reference vibration frequency when the linear generator is driven exceeds a threshold. death,
The threshold is determined based on the reference vibration frequency and a drive stop frequency for stopping the drive of the linear generator.
Power generation controller. In the power generation control device according to claim 2 or 3,
further comprising a reference vibration frequency updating unit that sets the vibration frequency when the linear generator is driving as the reference vibration frequency when the power generation characteristic acquisition unit acquires the power generation characteristics of the power generation device,
Power generation controller. In the power generation control device according to any one of claims 1 to 4,
The power generation control device, wherein the energy wave is a sound wave obtained by a thermoacoustic phenomenon.

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