Power generation system, control device, and control method

Abstract

The present invention comprises: a generator (12) that generates power using the rotation of a motor (22) that drives a rotating body; a transmission (11) that is interposed between the motor (22) and the generator (12) and adjusts a transmission ratio between the motor (22) and the generator (12); and a control unit (15) that controls the transmission ratio to be adjusted by the transmission (11). The control unit (15) adjusts the transmission ratio so that the rotation speed of the generator (15) decreases when at least one of the rotation speed of the motor and a sensor value obtained by a sensor that detects the operating state of the rotating body is less than a preset threshold value.

Description

Power generation system, control device, and control method

[0001] The present invention relates to a power generation system, a control device, and a control method.

[0002] A power generation system that converts the driving force of a rotating body into electric power is known. Japanese Unexamined Patent Publication No. 2022-182811 (JP2022-182811A) discloses an assisted bicycle including a generator that meshes with a bicycle chain and a power storage means that stores electric power generated by the generator.

[0003] On the other hand, in facilities such as factories, there has been a demand for effectively utilizing surplus electric power. However, there has been a problem that if the amount of generated power is too large, it hinders the necessary power supply in the facility.

[0004] The present disclosure has been made in consideration of such points, and an object of the present disclosure is to provide a power generation system, a control device, and a control method capable of effectively utilizing surplus power while ensuring necessary power supply.

[0005] The power generation system of the present invention includes: a generator that generates power using power of rotation of a driving body that drives a rotating body; a transmission that is interposed between the driving body and the generator and adjusts a gear ratio between the driving body and the generator; and a control unit that controls the gear ratio by the transmission, wherein the control unit adjusts the gear ratio such that the rotation speed of the generator decreases when at least one of a sensor value obtained by a sensor that detects an operating state of the rotating body and the rotation speed of the driving body is less than a preset threshold value.

[0006] In the power generation system of the present invention, the transmission is a multi-stage gear, and the control unit may shift down the gear of the transmission by one stage when at least one of the sensor value and the rotation speed is less than the threshold value.

[0007] In the power generation system of the present invention, the control unit may adjust the gear ratio such that the rotation speed of the generator decreases when the sensor value is less than a sensor threshold value and the rotation speed is less than a rotation speed threshold value.

[0008] The power generation system of the present invention may further include a setting unit that sets the threshold value in response to user operation.

[0009] In the power generation system of the present invention, the threshold value may be set according to the operating schedule of the rotating body.

[0010] In the power generation system of the present invention, the rotating body may be a pump, conveyor, agitator, or fan.

[0011] The control device of the present invention is a control device that controls the gear ratio by a transmission that interposes between a generator that generates electricity using the rotational power of a drive body that drives a rotating body and the drive body, and adjusts the gear ratio between the drive body and the generator, characterized in that when at least one of a sensor value obtained by a sensor that detects the operating state of the rotating body and the rotational speed of the drive body is less than a preset threshold, the gear ratio is adjusted so that the rotational speed of the generator decreases.

[0012] The control method of the present invention is an information processing method performed by a control unit that controls the gear ratio by a transmission that interposes between a generator that generates electricity using the rotation of a motor that drives a rotating body and the drive body, and adjusts the gear ratio between the drive body and the generator, characterized in that it includes a step of adjusting the gear ratio so that the rotation speed of the generator decreases when at least one of a sensor value obtained by a sensor that detects the operating state of the rotating body and the rotation speed of the drive body is less than a preset threshold.

[0013] This is an overall configuration diagram of the power generation system according to the first embodiment. This is a side view of the motor, transmission, and generator. This is a perspective view of the motor, transmission, and generator. This is an internal configuration diagram of the transmission. This is a flowchart showing the control of the transmission. This is an overall configuration diagram of the power generation system according to the second embodiment. This is an overall configuration diagram of the power generation system according to the third embodiment. This is an overall configuration diagram of the power generation system according to the fourth embodiment.

[0014] Embodiments of the present invention will be described below with reference to the drawings.

[0015] (First Embodiment) Figure 1 is an overall configuration diagram of the power generation system 1 according to the first embodiment. The power generation system 1 is a system that generates electricity by utilizing the rotation of a motor 22, which is a drive unit that drives a pump 21, which is a rotating body. The pump 21 is used, for example, to drain water in a factory or other facility. Pumps 21 in such facilities are often designed to have a higher operating capacity than that required for normal operation. In other words, pumps 21 in such facilities are often designed to be supplied with more power than is required for normal operation. As a result, surplus power is generated during normal operation. The power generation system 1 of this embodiment generates electricity using this surplus power.

[0016] The power generation system 1 mainly comprises a transmission 11, a generator 12, a power control unit 13, a storage battery 14, a control unit 15, and a generator sensor 33. The transmission 11 is installed between the motor 22 and the generator 12, and the generator 12 changes the rotational driving force of the motor 22 and transmits it to the generator 12. The electricity generated by the generator 12 is stored in the storage battery 14 under the control of the power control unit 13.

[0017] A lithium battery is used as the storage battery 14. Other examples include a capacitor, a supercapacitor, etc., for the storage battery 14.

[0018] Furthermore, a water pressure sensor 31 is provided near the pump 21, a motor sensor 32 is provided near the motor 22, and a generator sensor 33 is provided near the generator 12. The water pressure sensor 31 is a pressure sensor that detects water pressure as its sensor value. The motor sensor 32 and the generator sensor 33 are rotation sensors that both detect rotational speed (rpm).

[0019] The control unit 15 controls the gear ratio in the transmission 11 based on the detection results of the water pressure sensor 31 and the motor sensor 32. The control unit 15 also controls the amount of power generated based on the detection results of the generator sensor 33. The control unit 15 may be provided integrally with other components of the power generation system such as the transmission 11, or, in another example, it may be provided as a standalone device.

[0020] Figure 2 is a side view of the area around the motor 22, transmission 11, and generator 12. Figure 3 is a perspective view of the area around the motor 22, transmission 11, and generator 12.

[0021] The motor shaft 41 of the motor 22 is connected to the transmission 11. The output shaft 42 of the transmission 11 is connected to the generator 12. A motor sensor 32 is provided near the motor shaft 41, and a generator sensor 33 is provided near the generator 12.

[0022] Figure 4 is an internal diagram of the transmission 11. The gear 410 on the motor shaft 41 meshes with the gear 410 on the input shaft 43 of the transmission 11. In the transmission 11, the gear ratio is changed by the meshing of the input shaft 43 and the output shaft 42 with their respective gears. For example, as shown in Figure 4, the gear 431 on the input shaft 43 meshes with the gear 421 on the output shaft 42 to set the gear to the first stage. Also, the gear 432 on the input shaft meshes with the gear 422 on the output shaft 42 to set the gear to the second stage. Thus, the transmission 11 of this embodiment is a multi-stage gear that can set six gear ratios by the meshing of the gears 431 to 436 on the input shaft 43 with the gears 421 to 426 on the output shaft 42.

[0023] Figure 5 is a flowchart showing the control of the transmission 11 by the control unit 15. The control unit 15 acquires water pressure as a detection result from the water pressure sensor 31 (step S100). The control unit 15 further acquires motor rotation speed as a detection result from the motor sensor 32 (step S102). Next, the control unit 15 determines whether the water pressure acquired in step S100 and the motor rotation speed acquired in step S102 satisfy preset conditions (step S104). Here, the conditions are that the detected water pressure is less than the water pressure threshold and the detected motor rotation speed is less than the rotation speed threshold. Here, the water pressure threshold and rotation speed threshold are assumed to be preset. The water pressure threshold is an example of a sensor threshold.

[0024] For example, suppose it is possible to drain wastewater from a factory using 80% of the motor's maximum output. In this case, the remaining 20% ​​can be used for power generation. Therefore, values ​​corresponding to 80% of the motor's maximum output are set as the water pressure threshold and rotational speed threshold. By maintaining the water pressure and motor rotational speed above these thresholds, it is possible to generate electricity while preventing a shortage of power needed for normal drainage.

[0025] If the water pressure and motor rotation speed meet the conditions (Y in step S104), the control unit 15 controls the transmission 11 to downshift by one gear (step S106), and then proceeds to step S100. By downshifting the gear in this way, the amount of power generated is reduced, and it is expected that the water pressure and motor rotation speed will increase.

[0026] On the other hand, if the condition is not met (N in step S104), the control unit 15 proceeds to step S100 without changing the gear. Then, the control unit 15 periodically repeats the process from step S100 onward.

[0027] As described above, in the power generation system 1 of this embodiment, when the water pressure is below the water pressure threshold and the motor rotation speed is below the motor rotation speed threshold, the rotation speed of the generator 12 is reduced. This makes it possible to generate power while preventing a shortage of power for drainage by the pump 21. In other words, the power generation system 1 of this embodiment can effectively utilize surplus power while ensuring the necessary power supply to the pump 21. In facilities such as factories, equipment equipped with motors with ample specifications is often introduced to prevent factory operations from stopping and to accommodate larger equipment. In such cases, there was a problem that power was wasted when the equipment was in operation. In contrast, in the power generation system 1 of this embodiment, surplus power can be effectively utilized by generating power with the generator 12 using surplus power as described above.

[0028] As a first modification of the first embodiment, the sensor provided on the pump 21 can be any sensor capable of detecting the operating state of the pump 21, and is not limited to a water pressure sensor. Another example of a sensor provided on the pump 21 is a flow sensor that detects the flow rate.

[0029] As a second variation, the control unit 15 may only require that the water pressure be below a water pressure threshold, and if this condition is met, it may downshift by one gear. Another example is that the control unit 15 may only require that the motor rotation speed be below a rotation speed threshold, and if this condition is met, it may downshift by one gear. Thus, the condition for lowering the gear ratio may be that at least one of the water pressure and motor rotation speed is below a threshold.

[0030] As a third modification, the transmission 11 may be a continuously variable transmission. Furthermore, the control unit 15 only needs to control the transmission 11 so that the rotational speed of the generator 12 decreases when the water pressure and motor rotational speed meet the conditions, and the specific control for this purpose is not limited to the embodiment. In addition, the control unit 15 may set the rotational speed of the generator 12 to zero, that is, stop the generator 12, when the water pressure and motor rotational speed meet the conditions.

[0031] As a fourth variation, the water pressure threshold and rotation speed threshold may be set according to user operation. In this case, the power generation system 1 further includes a setting unit for receiving user operation. This makes it possible, for example, to set according to the operating schedule of the pump 21 as a rotating body. Here, the operating schedule is assumed to specify the amount of electricity required by the pump 21 in each time period.

[0032] As a fifth variation, the water pressure threshold and rotational speed threshold may be set in advance according to the operating schedule of the pump 21 as a rotating body. This makes it possible to generate electricity according to the amount of power required to operate the pump 21.

[0033] As a sixth variation, the drive unit that drives the rotating body is not limited to a motor. Other examples include an engine or the like. Furthermore, the generator only needs to utilize the rotational power of the drive unit, and can generate electricity by directly utilizing the rotational power of the motor or by utilizing it indirectly through other components.

[0034] (Second Embodiment) Next, the differences between the second embodiment and the first embodiment will be mainly described. Figure 6 is a diagram of the configuration of the power generation system 1 of the second embodiment. The power generation system 1 of the second embodiment generates electricity by utilizing the rotation of the motor 24 of the conveyor 23. The conveyor 23 is used, for example, to transport goods in a factory or other facility. A torque sensor 34 is provided near the rotation axis of the conveyor 23, and torque is obtained from the torque sensor 34 as a detection result indicating the operating state of the conveyor 23 as a rotating body.

[0035] In this case, the control unit 15 lowers the gear of the transmission 11 by one step if the torque and motor rotation speed meet the conditions. The conditions are that the torque is less than the torque threshold and the motor rotation speed is less than the motor rotation speed threshold. The torque threshold is assumed to be a preset value. The configuration of the power generation system 1 in the second embodiment is the same as that of the power generation system in the first embodiment.

[0036] (Third Embodiment) Next, the differences between the third embodiment and the other embodiments will be mainly described. Figure 7 is a diagram of the power generation system 1 of the third embodiment. The power generation system 1 of the third embodiment generates electricity by utilizing the rotation of the motor 26 of the fan 25. The fan 25 is, for example, a fan of a ventilation fan or air conditioner installed in a facility such as a factory. An airflow sensor 35 is provided near the fan 25, and the airflow sensor 35 detects the wind speed. The wind speed is obtained from the airflow sensor 35 as a detection result indicating the operating state of the fan 25 as a rotating body. Thus, the operating state includes not only the state of the rotating body itself, but also the surrounding state caused by the operation of the rotating body.

[0037] In this case, the control unit 15 lowers the gear of the transmission 11 by one step if the wind speed and motor rotation speed meet the conditions. The conditions are that the wind speed is less than the wind speed threshold and the motor rotation speed is less than the motor rotation speed threshold. The airflow threshold is assumed to be a preset value. The other configurations of the power generation system 1 of the third embodiment are the same as those of the power generation systems of the other embodiments.

[0038] (Fourth Embodiment) Next, the fourth embodiment will be described, mainly focusing on the differences from the other embodiments. Figure 8 is a diagram of the power generation system 1 of the fourth embodiment. The power generation system 1 of the fourth embodiment generates electricity by utilizing the rotation of the motor 28 of the agitator 27. The agitator 27 is used, for example, in facilities such as factories to stir liquids.

[0039] In this case, the control unit 15 lowers the gear of the transmission 11 by one step if the motor speed is below the motor speed threshold. The other configurations of the power generation system 1 of the fourth embodiment are the same as those of the power generation systems of the other embodiments.

[0040] As described above, in all embodiments of the power generation system 1, when the operating conditions of the rotating body are met, the rotational speed of the generator can be reduced to ensure the necessary power supply to the rotating body while effectively utilizing surplus power.

[0041] The embodiments described above are merely examples for carrying out the present invention, and various other embodiments can be adopted. For example, various modifications and changes are possible within the scope of the gist of the present invention as described in the claims, such as applying one modification to another. For example, some of the components of the above embodiments may be omitted, or the order of processing may be changed or omitted.

[0042] In the power generation system, control device, and control method of the present embodiment configured as described above, the power generation system includes: a generator 12 that generates power using rotational power of a driving body that drives a rotating body; a transmission 11 interposed between the driving body and the generator 12 for adjusting a gear ratio between the driving body and the generator 12; and a control unit 15 that controls the gear ratio of the transmission 11. When at least one of a sensor value obtained by a sensor that detects an operating state of the rotating body and the rotation speed of the driving body is less than a preset threshold, the control unit 15 adjusts the gear ratio such that the rotation speed of the generator 12 decreases. Therefore, surplus power can be effectively utilized while ensuring necessary power supply to the rotating body.

[0043] Further, in the power generation system, control device, and control method of the present embodiment, the transmission 11 is a multi-stage gear, and the control unit 15 may shift down the gear of the transmission 11 by one stage when at least one of the sensor value and the rotation speed is less than the threshold. Thereby, the rotation speed of the generator 12 can be gradually reduced.

[0044] Further, in the power generation system, control device, and control method of the present embodiment, when the sensor value is less than a sensor threshold and the rotation speed is less than a rotation speed threshold, the control unit 15 may adjust the gear ratio such that the rotation speed of the generator 12 decreases. Thereby, the operating state of the rotating body can be determined according to the sensor value and the rotation speed.

[0045] Further, in the power generation system, control device, and control method of the present embodiment, a setting unit that sets the threshold in accordance with a user operation may be further provided. Thereby, the threshold can be set by a user operation.

[0046] Further, in the power generation system, control device, and control method of the present embodiment, the threshold may be set according to an operation schedule of the rotating body. Thereby, surplus power can be effectively utilized in accordance with the operation schedule.

[0047] Furthermore, in the power generation system, control device, and control method of this embodiment, the rotating body may be a pump 21. Alternatively, the rotating body may be a conveyor 23, a stirrer 27, or a fan 25. Even in the operation of these rotating bodies, it is possible to effectively utilize surplus power while ensuring the necessary power supply to the rotating body.

Claims

1. A power generation system comprising: a generator that generates electricity using the rotational power of a drive unit that drives a rotating body; a transmission that interposes between the drive unit and the generator and adjusts the gear ratio between the drive unit and the generator; and a control unit that controls the gear ratio by the transmission, wherein the control unit adjusts the gear ratio so that the rotation speed of the generator decreases when at least one of a sensor value obtained by a sensor that detects the operating state of the rotating body and the rotation speed of the drive unit is below a preset threshold.

2. The power generation system according to claim 1, wherein the transmission is a multi-stage gear, and the control unit lowers the gear of the transmission by one step when at least one of the sensor value and the rotational speed is less than the threshold.

3. The power generation system according to claim 1 or 2, wherein the control unit adjusts the gear ratio so that the rotational speed of the generator decreases when the sensor value is less than a sensor threshold and the rotational speed is less than a rotational speed threshold.

4. The power generation system according to any one of claims 1 to 3, further comprising a setting unit for setting the threshold in response to user operation.

5. The power generation system according to any one of claims 1 to 3, wherein the threshold is set according to the operating schedule of the rotating body.

6. The power generation system according to any one of claims 1 to 5, wherein the rotating body is a pump, conveyor, agitator, or fan.

7. A control device that controls the gear ratio of a drive unit and a generator, which generates electricity using the rotational power of a drive unit that drives a rotating body, and a transmission that interposes between the drive unit and the generator, wherein the control device adjusts the gear ratio so that the rotational speed of the generator decreases when at least one of a sensor value obtained by a sensor that detects the operating state of the rotating body and the rotational speed of the drive unit is less than a preset threshold.

8. An information processing method performed by a control unit that controls the gear ratio by a transmission that interposes between a generator that generates electricity using the rotational power of a drive unit that drives a rotating body and the drive unit, the control method comprising the step of adjusting the gear ratio so that the rotational speed of the generator decreases when at least one of a sensor value obtained by a sensor that detects the operating state of the rotating body and the rotational speed of the drive unit is less than a preset threshold.

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