Hydroelectric power generation apparatus, hydroelectric power supply system, hydroelectric power supply method, and program

Abstract

To provide a hydroelectric power generation device, a hydroelectric power supply system, a hydroelectric power supply method, and a program that can stably supply DC power while keeping costs down. [Solution] The hydroelectric power generation device according to the present disclosure comprises a water turbine that converts the potential energy of water into kinetic energy, a rotating shaft connected to the water turbine, a generator that converts the kinetic energy from the rotation of a rotor connected to the rotating shaft into DC power, a dummy load section equipped with a resistor that consumes power, and a dummy load control section that controls the connection of the dummy load section to the output of the generator so that the rotational speed of the rotating shaft is within a predetermined range.

Description

Technical Field

[0001] The present disclosure relates to a hydroelectric power generation device, a hydroelectric power supply system, a hydroelectric power supply method, and a program.

Background Art

[0002] Small-scale hydroelectric power generation systems with a power generation capacity of 10,000 kW or less are known. Since small-scale hydroelectric power generation systems generate electricity using agricultural or industrial water, the amount of power generated is small. In order to recover the investment through the revenue from selling the generated electricity, a reduction in the overall cost of small-scale hydroelectric power generation systems has been demanded.

[0003] In addition, the opening degree of mechanisms such as mechanical guide vanes and needle valves that adjust the amount of fluid flowing into the waterwheel of a small-scale hydroelectric power generation system changes depending on the effective head (the position energy on the fluid side). Therefore, it is difficult to theoretically predict the setting of the opening degree according to the variation of the effective head.

[0004] Therefore, Patent Document 1 below discloses a control device for a power generation waterwheel equipped with a dummy load governor that can control the waterwheel rotation speed by adjusting the power generation amount with an electrical mechanism (dummy load) and automatically absorb the variation of the effective head.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the hydroelectric power grid connection system described in Patent Document 1 above connects to the existing AC power grid and could not charge batteries or other storage devices with the electricity generated by hydroelectric power. Furthermore, in order to promote the introduction of renewable energy with a view to future carbon neutrality, it was necessary to reduce the cost of hydroelectric power systems.

[0007] In light of the above issues, this disclosure aims to provide a hydroelectric power generation device, a hydroelectric power supply system, a hydroelectric power supply method, and a program that can stably supply DC power while keeping costs down. [Means for solving the problem]

[0008] To solve the above-mentioned problems and achieve the objectives, the hydroelectric power supply system according to this disclosure comprises a water turbine that converts the potential energy of water into kinetic energy, a rotating shaft connected to the water turbine, a generator that converts the kinetic energy from the rotation of a rotor connected to the rotating shaft into DC power, a dummy load section equipped with a resistor that consumes power, and a dummy load control section that controls the connection of the dummy load section to the output of the generator so that the rotational speed of the rotating shaft is within a predetermined range.

[0009] To solve the above-mentioned problems and achieve the objectives, the hydroelectric power supply system according to this disclosure comprises a hydroelectric power generator, an outlet electrically connected to a power grid, a transformer that changes the voltage of AC power from the power grid, a rectifier that rectifies the AC current from the power grid into a DC current of a predetermined voltage or less, and a load that consumes power, the load being electrically connected to the output of the generator.

[0010] To solve the above-mentioned problems and achieve the objectives, the hydroelectric power supply method according to this disclosure is a hydroelectric power supply method using a hydroelectric power supply system, and includes the steps of: acquiring the rotational speed of the rotating shaft; and controlling the connection of the dummy load to the output of the generator so that the rotational speed of the rotating shaft is within a predetermined range.

[0011] To solve the above-mentioned problems and achieve the objectives, the program relating to this disclosure is a program that causes a computer of a hydroelectric power supply system to execute processing, and includes the steps of: acquiring the rotational speed of the rotating shaft; and controlling the connection of the dummy load to the output of the generator so that the rotational speed of the rotating shaft is within a predetermined range. [Effects of the Invention]

[0012] According to this disclosure, it is possible to provide a hydroelectric power generation apparatus, a hydroelectric power supply system, a hydroelectric power supply method, and a program that can stably supply DC power while keeping costs down. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a diagram illustrating the overview of the hydroelectric power supply system related to this disclosure. [Figure 2] Figure 2 shows an example of the configuration of a hydroelectric power supply system related to this disclosure. [Figure 3] Figure 3 is a diagram showing an example configuration of a first embodiment of the control device for a hydroelectric power supply system according to this disclosure. [Figure 4] Figure 4 shows an example of information stored in the measurement value storage unit of the control device for the hydroelectric power supply system according to this disclosure. [Figure 5] Figure 5 is a diagram illustrating the control of a second embodiment of the control device for a hydroelectric power supply system according to this disclosure. [Figure 6] Figure 6 is a flowchart showing the control flow of a second embodiment of the control device for a hydroelectric power supply system according to this disclosure. [Figure 7] Figure 7 shows an example of the configuration of the dummy load section of the third embodiment of the control device for a hydroelectric power supply system according to this disclosure. [Figure 8] Figure 8 shows an example of the configuration of a power supply device for a hydroelectric power supply system according to this disclosure.

Best Mode for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present disclosure will be described in detail based on the drawings. Note that the present disclosure is not limited by the embodiments described below.

[0015] (Overview of Hydroelectric Power Supply System) First, the hydroelectric power supply system 1 according to the present disclosure will be described with reference to FIG. 1. FIG. 1 is a diagram for explaining the overview of the hydroelectric power supply system according to the present disclosure. As shown in FIG. 1, the hydroelectric power supply system 1 according to the present disclosure includes a hydroelectric power generation device 10 provided beside a waterway R such as a river.

[0016] The hydroelectric power generation device 10 takes in water from an agricultural waterway, an industrial waterway, or a water supply and sewerage system, etc., rotates the waterwheel 12 by the potential energy of the water, converts it into kinetic energy by the rotation of the waterwheel 12, and then generates electricity by rotating the generator 14 by the rotating shaft 16 connected to the waterwheel 12. Note that a mechanism for inhibiting the inflow of fallen leaves such as plants, driftwood, and aquatic organisms may be provided in the water distribution path through which water passes from a waterway such as a river leading to the hydroelectric power generation device 10.

[0017] As shown in FIG. 1, water is taken in from the water intake WI provided in a waterway R such as a river, passes through a pipeline WP1, etc., and is supplied to the hydroelectric power generation device 10. The water after rotating the waterwheel 12 of the hydroelectric power generation device 10 flows back to the waterway through the pipeline WP2 from the water discharge WO connected to the waterway such as a river. Thus, even when not consuming the flowing water of the river, when using the flowing water of the river, procedures under the River Law are required. Note that the arrangement and structure of pipelines for supplying water to the hydroelectric power generation device 10 are not limited to those shown in FIG. 1 and may be any other arbitrary arrangement and structure.

[0018] In addition, the effective head that determines the amount of kinetic energy generated by the waterwheel 12 is the total pressure difference of the water immediately before and immediately after the waterwheel 12. This is obtained by subtracting the flow loss in the pipeline from the static head, which is the water level difference when the waterwheel 12 in the water channel is stopped. However, since the flow loss in the pipeline varies depending on the water flow rate, it changes depending on the operating state of the waterwheel 12.

[0019] Here, small-scale hydropower generation installed beside a river or the like as shown in Fig. 1 refers to those with a power generation capacity of 10,000 kW or less. For example, it may be a 50 kW one equipped with a set of hydropower generation devices 10 in a container installed beside a river. Small-scale hydropower generation aims to achieve a zero balance of primary energy consumption from the perspective of carbon neutrality. When it becomes a target for assistance such as ZEH (Net Zero Energy House) or ZEB (Net Zero Energy Building), it can be expected to gain momentum for future demand expansion.

[0020] In addition, the hydropower generation power supply system 1 creates renewable energy and has the potential to effectively utilize unused resources, so an increase in future demand is expected. However, due to the complexity of the application procedures of the above-mentioned River Law and the need to improve the profitability of projects using small-scale hydropower generation, reducing the cost of the entire business activity has been an issue.

[0021] (Configuration of Hydropower Generation Power Supply System) Next, the configuration of the hydropower generation power supply system 1 according to the present disclosure will be described using Fig. 2. Fig. 2 is a diagram showing a configuration example of the hydropower generation power supply system according to the present disclosure. As shown in Fig. 2, the hydropower generation power supply system 1 according to the present disclosure includes a hydropower generation device 10 and a power supply device 200.

[0022] The hydropower generation device 10 includes a waterwheel 12, a rotating shaft 16, and a generator 14. The power supply device 200 includes an inverter 20, a secondary battery 30, and a load 40. These configurations will be described in order below.

[0023] The turbine 12 is an impeller that rotates using water power. The turbine 12 may be an impulse turbine such as a Pelton turbine, Turgo impulse turbine, or cross-flow turbine, which rotates the turbine by forcefully striking the blades with a stream of water. Alternatively, the turbine 12 may be a reaction turbine such as a Francis turbine or propeller turbine, which rotates the turbine by the water pressure of the flowing water, with the turbine placed in the water flow. In other words, the turbine 12 rotates when water strikes the impeller, thereby rotating the generator 14 connected to the rotating shaft 16 connected to the turbine 12. As will be explained later, since the generator 14 converts the generated AC power into DC power for output, the rotational speed of the turbine 12 is not restricted by the load or the frequency conditions of the power system, and a certain degree of fluctuation is permitted.

[0024] The generator 14 converts the kinetic energy from the rotation of the rotor into DC power. The generator 14 may be, for example, an alternator, which is a generator used in automobiles. An alternator is a permanent magnet synchronous generator in which a coil is the armature and a permanent magnet is the field. In a permanent magnet synchronous generator, one of the coils or permanent magnets is the rotor and the other is the stator, and by moving the distance between the coil and the permanent magnet closer or further away, the magnetic flux density passing through the coil is changed, and the current generated in the coil by electromagnetic induction is output as AC current. The generator 14 may be equipped with a rectifier using a diode, which converts the AC power of the alternator into DC power. By using a general-purpose alternator for automobiles as the generator 14, the cost of the hydroelectric power generation device 10 can be reduced.

[0025] The rotating shaft 16 connects the water turbine 12 and the generator 14, and the rotation of the water turbine 12 rotates the rotor of the generator 14. The rotating shaft 16 may be fastened to the rotor of the generator 14 by, for example, a coupling (shaft joint). In addition, a speed increaser may be provided between the rotating shaft 16 and the generator 14, if necessary, to rapidly convert the rotational speed transmitted from the water turbine 12 using a planetary gear mechanism or the like, thereby increasing the power generation efficiency of the generator 14. The rotational speed of the rotating shaft 16 is measured by a rotation sensor unit 150, which will be described later.

[0026] The inverter 20 converts the DC power output from the generator 14 into AC power. As shown in Figure 2, the inverter 20 is connected to the output of the generator 14 via the control device 100. The inverter 20 may be implemented by an inverter circuit. The inverter circuit includes a switching element and converts DC power into AC power by generating positive and negative voltages by changing the direction of the current by switching the switching element on and off.

[0027] The secondary battery 30 is a battery that can be repeatedly discharged by charging. As shown in Figure 2, the secondary battery 30 is connected between the control device 100 and the inverter 20, and DC power is supplied from the generator 14 via the control device 100. This allows the secondary battery 30 to be properly charged by the DC power output by the generator 14. The secondary battery 30 may be, for example, a lithium-ion battery, a lead-acid battery, a nickel-metal hydride battery, or a nickel-cadmium battery.

[0028] Load 40 is the object to which power is supplied after the DC power from the generator 14 has been converted to AC power. As shown in Figure 2, load 40 is connected to the generator 14 via an inverter 20 and a control device 100. That is, power converted to AC by the inverter 20 is supplied to load 40. Load 40 may be, for example, various electrical appliances or machinery used outdoors. Load 40 operates on power supplied from the hydroelectric power generation device 10.

[0029] As described above, the hydroelectric power supply system 1 rotates a turbine 12 using the potential energy of water, which in turn rotates a generator 14 connected to the turbine 12 via a rotating shaft 16. The AC power generated is converted to DC power and then supplied to a secondary battery 30. Therefore, the power generated by the turbine 12 can be stored appropriately.

[0030] (Control device configuration) (First Embodiment) Next, the configuration of the first embodiment of the control device 100 of the hydroelectric power supply system 1 according to this disclosure will be described with reference to Figure 3. Figure 3 is a diagram showing an example of the configuration of the first embodiment of the control device of the hydroelectric power supply system according to this disclosure. As shown in Figure 3, the first embodiment of the control device 100 of the hydroelectric power supply system 1 according to this disclosure comprises a dummy load unit 110, a storage unit 120, a control unit 130, an automatic voltage adjustment unit 140, a rotation sensor unit 150, a switching element unit 160, and a control signal transmission unit 170. These configurations will be described in order below.

[0031] The dummy load section 110 is a device that provides a load that simulates power consumption. The dummy load section 110 is connected to the output of the generator 14, with its connection controlled by the switching element section 160, which will be described later. The dummy load section 110 may be connected in parallel to the output of the generator 14. For example, the dummy load section 110 may be a resistor with a fixed electrical resistance value. Alternatively, the dummy load section 110 may be a variable resistor with a changeable electrical resistance value. For example, the resistance value can be changed by providing multiple resistors and changing the connection point of the wires connected to the resistors.

[0032] The memory unit 120 is a storage device that stores various types of information. The memory unit 120 comprises a main memory and an auxiliary storage device. The main memory may be implemented using semiconductor memory elements such as RAM (Random Access Memory), ROM (Read Only Memory), or flash memory. The auxiliary storage device may be implemented using a hard disk or an SSD (Solid State Drive), for example.

[0033] As shown in Figure 3, the storage unit 120 includes a measured value storage unit 121. The information stored in this configuration will be described in detail below.

[0034] The measurement value storage unit 121 stores the measurement values ​​of various measuring instruments. An example of the information stored in the measurement value storage unit 121 will be explained using Figure 4. Figure 4 is a diagram showing an example of the information stored in the measurement value storage unit of the control device for a hydroelectric power supply system according to this disclosure.

[0035] As shown in Figure 4, the measurement value storage unit 121 stores information related to items such as "time," "first measurement value," "second measurement value," and "third measurement value."

[0036] "Time" is information indicating the time when the measured values ​​such as the "first measured value," "second measured value," and "third measured value," which will be described later, were measured, and is expressed, for example, by year, month, day, hour, minute, and second. "First measured value," "second measured value," and "third measured value" are measurement data measured by the rotation speed sensor unit, etc., and may be, for example, the rotation speed measured by the rotation sensor unit 150 or the current value of the output of the generator 14.

[0037] In other words, Figure 4 shows an example in which the first measurement value "MDT#1-1", the second measurement value "MDT#2-1", and the third measurement value "MDT#3-1", measured at time "TM#1", are stored.

[0038] Furthermore, the information stored in the measurement value storage unit 121 is not limited to information relating to the items "time," "first measurement value," "second measurement value," and "third measurement value," but may also store other information related to arbitrary measurement values.

[0039] The control unit 130 is a controller that performs various calculations and functions. The control unit 130 is implemented by a CPU (Central Processing Unit) or MPU (Micro Processing Unit), etc., which executes various programs stored in the memory unit 120 using RAM as the working area. Alternatively, the control unit 130 may be implemented by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0040] As shown in Figure 3, the control unit 130 includes an acquisition unit 131, a dummy load control unit 132, an automatic voltage control unit 133, and a control signal output unit 134. The control unit 130 realizes these functions and performs these processes by reading and executing a program (software) from the storage unit 120. At least some of these functions of the control unit 130 may be realized by various electronic circuits. Furthermore, the control unit 130 may execute these processes with a single CPU, or it may have multiple CPUs and execute these processes with multiple CPUs. These configurations will be described in detail below.

[0041] The acquisition unit 131 acquires various types of information. For example, the acquisition unit 131 acquires the measured value of the rotation speed measured by the rotation sensor unit 150. Once the acquisition unit 131 has acquired the measured rotation speed from the rotation sensor unit 150, it stores the acquired rotation speed value along with the measurement date and time in the measurement value storage unit 121. Alternatively, the acquisition unit 131 may acquire the measured value of the output voltage of the generator 14 from a voltage measuring instrument that measures the output voltage of the generator 14. Once the acquisition unit 131 has acquired the measured value of the output voltage of the generator 14, it stores the acquired output voltage value along with the measurement date and time in the measurement value storage unit 121.

[0042] The dummy load control unit 132 controls the connection of the dummy load unit 110 to the output of the generator 14 based on the rotational speed of the rotating shaft connecting the turbine 12 and the generator 14. In other words, the dummy load control unit 132 adjusts the rotational speed of the turbine 12 by controlling the connection of the dummy load unit 110.

[0043] The dummy load control unit 132 may, for example, control the rotational speed of the rotating shaft to a predetermined value by PID (Proportional Integral Differential) control. PID control is a combination of proportional control, differential control, and integral control. Proportional control is used to control the system in accordance with the target value, integral control is used to reduce the deviation between the output value and the target value, and differential control is used to control the system in accordance with fluctuations caused by disturbances.

[0044] Here, in order to efficiently convert the potential energy of the water into kinetic energy using the water turbine 12, it is desirable to operate the water turbine 12 at a predetermined rotational speed that is highly efficient relative to the effective head described above. For this reason, the dummy load control unit 132 uses PID control to switch the connection of the dummy load unit 110 on and off based on the deviation between the predetermined rotational speed determined from the effective head and the measured rotational speed of the rotating shaft 16 by the rotation sensor unit 150. In other words, a predetermined rotational speed at which the water turbine 12 is highly efficient relative to the effective head is determined in advance, and this predetermined rotational speed is used as the target value for control. Note that the manipulated variable in PID control may take a continuous value from 0 to 1, and this value may be considered as a ratio to determine the on time within a certain period of time.

[0045] This allows for improved efficiency and control of the rotational speed of the rotating shaft for equipment protection by adjusting the amount of DC electricity flowing through the dummy load section 110 by switching the switching element on and off, similar to the charge level control of a secondary battery.

[0046] The automatic voltage control unit 133 controls the automatic voltage adjustment unit 140. Specifically, the automatic voltage control unit 133 monitors voltage fluctuations at the output of the generator 14 and, if the voltage value deviates from a predetermined range, generates a control signal to control the switching elements of the automatic voltage adjustment unit 140 so that the voltage value at the output of the generator 14 falls within the predetermined range. The automatic voltage control unit 133 may control the voltage, for example, by PID control.

[0047] The control signal output unit 134 outputs the generated control signals to the target equipment or device. That is, the control signal output unit 134 outputs the generated control signals to the control signal transmission unit, which then outputs them to the target equipment or device. The control signal output unit 134 outputs the generated control signals to the dummy load unit 110, the automatic voltage adjustment unit 140, etc.

[0048] The automatic voltage regulating unit 140 automatically stabilizes the output voltage of the generator 14. The automatic voltage regulating unit 140 is connected to the output of the generator 14. The automatic voltage regulating unit 140 may be an automatic voltage regulator (AVR). The automatic voltage regulator maintains a constant output voltage even if the input voltage fluctuates or the current flowing to the output side of the automatic voltage regulator fluctuates. The automatic voltage regulator may be implemented by, for example, a linear amplifier or a switching method. Based on the control commands of the automatic voltage control unit 133 described above, the automatic voltage regulating unit 140 automatically stabilizes the output voltage of the generator 14 so that the value of the output voltage of the generator 14 falls within a predetermined range.

[0049] The rotation sensor unit 150 is a measuring instrument that measures the rotational speed of the rotating shaft 16. The rotation sensor unit 150 may be implemented by, for example, an eddy current displacement sensor, which measures the rotational speed by detecting the change in displacement as the rotating shaft 16 passes over a gear-shaped target, keyway, etc., as a rotational pulse. Alternatively, the rotation sensor unit 150 may be a tachogenerator (tachometer generator). A tachogenerator is a DC generator that generates a DC current proportional to the rotational speed.

[0050] The switching element 160 is an element that switches the connection of the dummy load 110 to the output of the generator 14. The switching element 160 may be implemented, for example, by a relay that switches the on / off state of its contacts by the electromagnetic force generated by passing current through a coil, or by a MOSFET (Metal-Oxide Semiconductor Field-Effect Transistor). The switching element 160 switches the connection of the dummy load 110 to the output of the generator 14 based on the control signal generated by the dummy load control unit 132 and output from the control signal output unit 134.

[0051] The control signal transmission unit 170 transmits control signals to the target equipment or device. The control signal transmission unit 170 may be implemented by various electrical wiring connected to a control electronic circuit board, for example, by bundling multiple wires, each with an insulator covering a conductor such as copper, and covering them with an electrically insulating polyvinyl chloride (PVC) sheath to form a control signal cable. That is, the control signal transmission unit 170 may be connected to the dummy load unit 110, the automatic voltage adjustment unit 140, etc., by a control signal cable.

[0052] As described above, according to the first embodiment of the control device 100 of the hydroelectric power supply system 1 according to this disclosure, the rotational speed of the turbine 12 and the rotating shaft 16 connected to the generator 14 can be kept within a predetermined range. Therefore, the turbine 12 can be operated at a predetermined rotational speed that is highly efficient with respect to the effective head, and thus the conversion of the potential energy of the water into kinetic energy by the turbine 12 can be efficiently performed. Accordingly, it is possible to provide a hydroelectric power supply system 1 that can stably supply DC power.

[0053] (Control device configuration) (Second embodiment) Next, a second embodiment of the control device 100 of the hydroelectric power supply system 1 according to this disclosure will be described. In the second embodiment of the control device 100 of the hydroelectric power supply system 1 according to this disclosure, the processing of the dummy load control unit 132 of the control unit 130 differs from that of the first embodiment. As the other configurations are the same as those of the first embodiment of the control device 100 of the hydroelectric power supply system 1, the explanation of the same configurations as the first embodiment of the control device 100 of the hydroelectric power supply system 1 will be omitted below, and the processing of the dummy load control unit 132 of the control unit 130 will be described.

[0054] The dummy load control unit 132 controls the on / off state of the switching element unit 160 that switches the connection of the dummy load unit 110 to the output of the generator 14. When using the PID control described above, if the specifications of the turbine 12 and generator 14 or their application (fluid conditions) change, it is necessary to adjust the parameters used for PID control. With on / off control, the cost of adjusting parameters can be reduced. Specifically, the dummy load control unit 132 turns on the switching element unit 160 that switches the connection of the dummy load unit 110 to the output of the generator 14 when the rotational speed of the rotating shaft 16 exceeds the upper limit, and turns off the switching element unit 160 that switches the connection of the dummy load unit 110 to the output of the generator 14 when the rotational speed of the rotating shaft 16 exceeds the lower limit.

[0055] Here, using Figure 5, the control of the dummy load control unit 132 according to a second embodiment of the control device 100 according to the present disclosure will be explained. Figure 5 is a diagram illustrating the control of a second embodiment of the control device for a hydroelectric power supply system according to the present disclosure. As shown in Figure 5, the dummy load control unit 132 turns on the switching element unit 160 when the rotational speed (rotational speed) reaches an upper limit or a lower limit. In Figure 5, it is shown that the switching element unit 160 is turned on when the rotational speed (rotational speed) reaches an upper limit, causing the rotational speed (rotational speed) to start to decrease, and when the rotational speed (rotational speed) reaches a lower limit, the switching element unit 160 is turned off, and the rotational speed (rotational speed) increases, reaches an upper limit, and the switching element unit 160 is turned on, and this process is repeated.

[0056] Next, the flow of the control method according to the second embodiment of the control device 100 according to the present disclosure will be described using Figure 6. Figure 6 is a flowchart showing the flow of the control method according to the second embodiment of the control device for a hydroelectric power supply system according to the present disclosure.

[0057] First, the control device 100 acquires the rotational speed of the rotating shaft (step S101). Next, the control device 100 determines whether the rotational speed has reached the upper limit (step S102). If the rotational speed has reached the upper limit (step S102: Yes), the control device 100 turns on the connection to the dummy load unit 110 (step S103). Next, the control device 100 acquires the rotational speed of the rotating shaft (step S104). Next, the control device 100 determines whether the rotational speed has reached the lower limit (step S105). If the rotational speed has reached the lower limit (step S105: Yes), the control device 100 turns off the connection to the dummy load unit 110 (step S106). Next, the control device 100 returns to step S101 and executes the subsequent processing.

[0058] If, in step S102, the rotational speed has not reached the upper limit (step S102: No), the control device 100 returns to step S101 and executes the subsequent processes.

[0059] Furthermore, if the rotational speed has not reached the lower limit in step S105 (step S105: No), the control device 100 returns to step S104 and executes the subsequent processes.

[0060] This allows the rotational speed of the rotating shaft 16 connected to the turbine 12 and generator 14 to be appropriately controlled to a value between the upper and lower limits. The PID control used in the control device 100 described above requires adjustment of the control parameters when the turbine, generator, and their application (fluid conditions) change. With on / off control as in the second embodiment of the control device 100, the cost of adjusting the control parameters can be reduced. Therefore, it is possible to provide a hydroelectric power supply system 1 that can stably supply DC power.

[0061] (Control device configuration) (Third embodiment) Next, a third embodiment of the control device 100 for the hydroelectric power supply system 1 according to this disclosure will be described. The third embodiment of the control device 100 for the hydroelectric power supply system 1 according to this disclosure differs from the first embodiment in the configuration of the dummy load section 110. As the other configurations are the same as those of the first embodiment of the control device 100 for the hydroelectric power supply system 1, the following description will omit the explanation of the same configurations as the first embodiment of the control device 100 for the hydroelectric power supply system 1 and will instead describe the configuration of the dummy load section 110.

[0062] The dummy load section 110 will be described with reference to Figure 6. Figure 6 is a diagram showing an example of the configuration of the dummy load section of the third embodiment of the control device for the hydroelectric power supply system according to the present disclosure. As shown in Figure 6, the dummy load section 110 of the third embodiment of the control device 100 of the hydroelectric power supply system 1 according to the present disclosure comprises a resistor 111 and a fan 112. These configurations will be described in order below.

[0063] Resistor 111 is a resistor that consumes power. Resistor 111 does not need to be a variable resistor whose electrical resistance value can be changed; it may be a resistor whose resistance value is set to a predetermined value.

[0064] The fan 112 blows air by rotating an impeller with an electric motor. The generator 14 and the resistors in the dummy load section 110 mentioned above have parts that generate heat due to Joule heating. Therefore, in the third embodiment of the control device 100 of the hydroelectric power supply system 1 according to this disclosure, instead of making the entire dummy load section 110 a resistor, a part of it is made into an impeller connected to an electric motor to cool the generator 14 and the resistors 111 of the dummy load section 110.

[0065] The fan 112 may also control its rotation speed based on the temperature measured by a thermometer such as a thermocouple at the temperature of the heat-generating parts such as the generator 14 and the resistors of the dummy load section 110. For example, the fan 112 may be operated when the temperature of the heat-generating parts such as the generator 14 and the resistors of the dummy load section 110 exceeds a predetermined temperature, or the fan 112 may be operated so that the temperature of the heat-generating parts such as the generator 14 and the resistors of the dummy load section 110 remains within a predetermined range.

[0066] As a result, a fan 112 is provided in the dummy load section 110 used to adjust the rotational speed of the rotating shaft 16 connecting the water turbine 12 and the generator 14. This allows for proper cooling by blowing air onto the heat-generating parts of the generator 14 and resistor 111, in addition to adjusting the rotational speed of the rotating shaft 16. Therefore, power generation by the generator 14 can be performed efficiently. Consequently, a hydroelectric power supply system 1 that can stably supply DC power can be provided.

[0067] (Control device configuration) (Fourth embodiment) Next, a fourth embodiment of the control device 100 of the hydroelectric power supply system 1 according to this disclosure will be described. Figure 8 is a diagram showing an example of the configuration of the power supply device of the hydroelectric power supply system according to this disclosure. As shown in Figure 8, the power supply device of the hydroelectric power supply system includes an inverter 20, a secondary battery 30, a load 40, a reverse current prevention diode 50, a rectifier 60, a transformer 70, and an outlet 80. These configurations will be described in order below.

[0068] The inverter 20 converts direct current to alternating current. As shown in Figure 8, the inverter 20 is configured to be connectable to both the direct current from the generator 14 and the direct current converted from the alternating current from the power grid.

[0069] The secondary battery 30 is a battery that can be repeatedly discharged by charging. The secondary battery 30 may be connected in parallel to the output of the generator 14. The secondary battery 30 is the same as described above, so its explanation will be omitted.

[0070] The reverse current blocking diode 50 allows the DC power supplied from the generator 14 to flow in only one direction. The reverse current blocking diode 50 may be implemented using a semiconductor diode. As shown in Figure 8, the reverse current blocking diode 50 may be installed between the control device 100 and the load 40 provided via the inverter 20. The polarity of the reverse current blocking diode 50 is such that the anode faces the generator 14.

[0071] The rectifier 60 allows current to flow in only one direction, that is, it rectifies alternating current and converts it into direct current. The rectifier 60 may be implemented by, for example, a semiconductor diode. The semiconductor diode may be, for example, a pn junction diode to achieve current rectification. As shown in Figure 8, the rectifier 60 is electrically connected to the power system via the outlet 80 and rectifies the alternating current power supplied from the power system and converts it into direct current power.

[0072] The transformer 70 changes the voltage of the input alternating current. For example, the transformer 70 may be a transformer comprising a plurality of magnetically coupled coils and magnetic circuits provided inside and outside the coils. The transformer passes an alternating current through the primary coil to generate a fluctuating magnetic field, which is transmitted to a secondary coil coupled by mutual inductance, and the secondary coil converts it into an alternating current with a changed voltage. The transformer 70 reduces the voltage of the DC power output from the rectifier 60 to a predetermined voltage or less (for example, 12V or less).

[0073] The outlet 80 is electrically connected to a power system not shown in Figure 8. For example, the outlet 80 may be connected to the power lines of a power system installed on a utility pole. In other words, the outlet 80 is electrically connected to the power system and receives AC power from the power system.

[0074] As described above, according to the hydroelectric power supply system 1 of this disclosure, when the output voltage of the generator 14 exceeds a predetermined voltage value (e.g., 12V) during the operation of the generator 14 or when the secondary battery 30 is outputting power, power from the power grid is not supplied to the load 40. When the generator 14 is stopped or the secondary battery 30 is not sufficiently charged, and the output voltage of the generator 14 falls below the DC output voltage of the rectifier 60 (e.g., 12V), power is supplied to the load 40 from the power grid. These functions enable the supply of power to the load 40 without interruption, regardless of the operation of the turbine 12. Therefore, it is possible to provide a hydroelectric power supply system 1 that can stably supply DC power.

[0075] (Structure and effect) The hydroelectric power generation device 10 according to the first embodiment comprises a water turbine 12 that converts the potential energy of water into kinetic energy, a rotating shaft 16 connected to the water turbine 12, a generator 14 that converts the kinetic energy from the rotation of a rotor connected to the rotating shaft 16 into electrical energy, a dummy load unit 110 equipped with a resistor that consumes power, and a dummy load control unit 132 that controls the connection of the dummy load unit 110 to the output of the generator 14 so that the rotational speed of the rotating shaft 16 is within a predetermined range.

[0076] This configuration allows the rotational speed of the rotating shafts connected to the turbine 12 and generator 14 to be kept within a predetermined range. Therefore, the turbine 12 can be operated at a specific rotational speed that is highly efficient with respect to the effective head, thereby enabling efficient conversion of water into kinetic energy by the turbine 12. Consequently, a hydroelectric power generation device 10 that can stably supply DC power can be provided.

[0077] The hydroelectric power generation apparatus 10 according to the second embodiment is the same as the hydroelectric power generation apparatus 10 according to the first embodiment, wherein the dummy load control unit 132 controls the on / off connection of the dummy load unit 110 to the output of the generator 14 by PID control so that the rotational speed of the rotating shaft 16 is within a predetermined range.

[0078] With this configuration, the rotational speed of the turbine 12 and the rotating shaft connected to the generator 14 can be appropriately controlled by PID control to stay within a predetermined range. As a result, the turbine 12 can be operated at a specific rotational speed that is highly efficient with respect to the effective head, thereby enabling efficient conversion of kinetic energy by the turbine 12. Consequently, a hydroelectric power generation device 10 that can stably supply DC power can be provided.

[0079] The hydroelectric power generation apparatus 10 according to the third embodiment is the hydroelectric power generation apparatus 10 according to the first or second embodiment, wherein the dummy load control unit 132 turns on the connection of the dummy load unit 110 to the output of the generator 14 when the rotational speed of the rotating shaft 16 exceeds a predetermined upper limit, and turns off the connection of the dummy load unit 110 to the output of the generator 14 when the rotational speed of the rotating shaft 16 falls below a predetermined lower limit.

[0080] With this configuration, the rotational speed of the rotating shaft 16 connected to the turbine 12 and generator 14 can be appropriately controlled between an upper and lower limit by on / off control. On / off control reduces the cost of adjusting control parameters that would be required in the case of PID control. Therefore, it is possible to provide a hydroelectric power generation device 10 that can stably supply DC power.

[0081] The hydroelectric power generation apparatus 10 according to the fourth embodiment is a hydroelectric power generation apparatus 10 according to any one of the first to third embodiments, wherein the dummy load section 110 includes a generator 14 and a fan 112 for cooling the heat-generating parts of the resistor 111, in addition to the resistor 111.

[0082] With this configuration, a fan 112 is provided in the dummy load section 110 used to adjust the rotational speed of the rotating shaft 16 connecting the water turbine 12 and the generator 14. In addition to adjusting the rotational speed of the rotating shaft 16, the fan 112 can blow air onto the heat-generating parts of the generator 14 and resistor 111, allowing for proper cooling. As a result, power generation by the generator 14 can be performed efficiently. Therefore, a hydroelectric power generation device 10 that can stably supply DC power can be provided.

[0083] The hydroelectric power supply system 1 according to the fifth embodiment comprises a hydroelectric power generation device 10 according to any one of the first to fourth embodiments, an outlet 80 electrically connected to a power grid, a transformer 70 that changes the voltage of AC power from the power grid, a rectifier 60 that rectifies the AC current from the power grid into a DC current of a predetermined voltage or less, and a load 40 that consumes power, the load 40 being electrically connected to the output of the generator 14.

[0084] This configuration allows for a stable supply of DC power to the load 40 without interruption, regardless of the operation of the turbine 12. Therefore, it is possible to provide a hydroelectric power supply system 1 that can stably supply DC power.

[0085] The hydroelectric power supply system 1 according to the sixth embodiment comprises a hydroelectric power generation device 10 according to any one of the first to fourth embodiments, and a secondary battery 30 connected to the output of the generator 14 and capable of repeatedly discharging by being charged.

[0086] With this configuration, the DC power generated efficiently by rotating the water turbine 12 at an efficient rotational speed can be stably supplied to the secondary battery 30 from the hydroelectric power generator 10. Therefore, a hydroelectric power supply system 1 that can stably supply DC power can be provided.

[0087] The hydroelectric power supply method according to the seventh embodiment is a hydroelectric power supply method using the hydroelectric power supply system 1 according to the sixth embodiment, and includes the steps of: acquiring the rotational speed of the rotating shaft 16; and controlling the connection of the dummy load section 110 to the output of the generator 14 so that the rotational speed of the rotating shaft 16 is within a predetermined range.

[0088] This configuration allows the rotational speed of the rotating shafts connected to the turbine 12 and generator 14 to be kept within a predetermined range. As a result, the turbine 12 can be operated at a specific rotational speed that is highly efficient relative to the effective head, enabling efficient conversion of kinetic energy by the turbine 12 and supplying DC power to the secondary battery 30. Therefore, a hydroelectric power generation power supply method that can stably supply DC power can be provided.

[0089] The program according to the eighth embodiment is a program that causes the computer of the hydroelectric power supply system 1 according to the sixth embodiment to execute processing, and includes the steps of acquiring the rotational speed of the rotating shaft 16 and controlling the connection of the dummy load unit 110 to the output of the generator 14 so that the rotational speed of the rotating shaft 16 is within a predetermined range.

[0090] This configuration allows the rotational speed of the rotating shafts connected to the turbine 12 and generator 14 to be kept within a predetermined range. Therefore, the turbine 12 can be operated at a specific rotational speed that is highly efficient with respect to the effective head, enabling efficient conversion of kinetic energy by the turbine 12 and supplying DC power to the secondary battery 30. Consequently, a program that can stably supply DC power can be provided.

[0091] Although embodiments of the present disclosure have been described above, the embodiments are not limited to those described herein. Furthermore, the aforementioned components include those that can be easily conceived by those skilled in the art, those that are substantially the same, and those that fall within the so-called equivalent range. Moreover, the aforementioned components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the gist of the embodiments described above. [Explanation of Symbols]

[0092] 1. Hydroelectric power supply system 10 Hydroelectric power generation equipment 12 Waterwheels 14 Generators 16 Rotation axis 20 Inverters 30 Secondary battery 40 load 50 Reverse current protection diode 60 rectifier 70 Transformer 80 outlets 100 Control device 110 Dummy load section 111 Resistor 112 Fans 120 Storage section 121 Measurement Value Storage Unit 130 Control Unit 131 Acquisition Department 132 Dummy Load Control Unit 133 Automatic Voltage Control Unit 134 Control signal output section 140 Automatic voltage regulation unit 150 Rotation sensor section 160 Switching element section 170 Control signal transmission unit 200 Power supply equipment

Claims

1. A water turbine that converts the potential energy of water into kinetic energy, A rotating shaft connected to the aforementioned water turbine, A generator that converts the kinetic energy from the rotation of a rotor connected to the aforementioned rotating shaft into DC power, A dummy load section equipped with a resistor that consumes power, The system includes a dummy load control unit that controls the connection of the dummy load unit to the output of the generator so that the rotation speed of the rotating shaft is within a predetermined range. Hydroelectric power generation device.

2. The dummy load control unit controls the on / off connection of the dummy load unit to the generator output by PID control, thereby keeping the rotation speed of the rotating shaft within a predetermined range. The hydroelectric power generation apparatus according to claim 1.

3. The dummy load control unit turns on the connection to the generator output of the dummy load unit when the rotational speed of the rotating shaft exceeds a predetermined upper limit. When the rotational speed of the aforementioned rotating shaft falls below a predetermined lower limit, the connection to the generator output of the dummy load unit is turned off. The hydroelectric power generation apparatus according to claim 1.

4. The dummy load section includes, in addition to the resistor, the generator and a fan for cooling the heat-generating parts of the resistor. A hydroelectric power generation apparatus according to any one of claims 1 to 3.

5. A hydroelectric power generation apparatus according to any one of claims 1 to 3, An outlet that is electrically connected to the power grid, A transformer that changes the voltage of AC power from the power grid, A rectifier that rectifies AC current from the power system into DC current below a predetermined voltage, Equipped with a power-consuming load, The load is electrically connected to the output of the generator. A hydroelectric power supply system.

6. A hydroelectric power generation apparatus according to any one of claims 1 to 3, The system comprises a secondary battery that can be repeatedly discharged by being connected to the output of the generator and charged. A hydroelectric power supply system.

7. A method for supplying hydroelectric power using the hydroelectric power supply system described in claim 6, The steps include obtaining the rotational speed of the aforementioned rotating shaft, The step includes controlling the connection of the dummy load unit to the output of the generator so that the rotational speed of the rotating shaft is within a predetermined range, A method of supplying electricity from hydroelectric power.

8. A program that causes a computer in a hydroelectric power supply system according to claim 6 to perform processing, The steps include obtaining the rotational speed of the aforementioned rotating shaft, The step includes controlling the connection of the dummy load unit to the output of the generator so that the rotational speed of the rotating shaft is within a predetermined range, program.

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