Hydroelectric power generation system and method for designing same

Abstract

A method for designing a hydroelectric power generation system comprises the steps of: determining an initial head and an initial flow rate of a stream of water; selecting a target number of rotations of a turbine by inputting the initial head and the initial flow rate into a waterwheel model for calculating the number of rotations of the turbine from the head and the flow rate of the water flow, the waterwheel model including waterwheel design factors; calculating a computed number of rotations of the turbine according to the head and the flow rate of the water flow by computational fluid dynamics; comparing the target number of rotations and the computed number of rotations; changing the flow rate when the target number of rotations and the computed number of rotations do not match; when the target number of rotations and the computed number of rotations match, determining a final number of rotations of the turbine as the matching value; and calculating a power generation output by computing the output of the hydroelectric power system from the final number of rotations.

Description

Hydroelectric power generation system and its design method

[0001] The following description relates to hydroelectric power generation systems and their design methods.

[0002] As environmentally friendly demands for power generation increase, the demand for diverse power generation systems is also increasing. Hydroelectric power systems generate electricity by utilizing the flow of fluids (or "water currents").

[0003] For example, a hydroelectric power system includes a turbine, whose blades are moved by the current of water, such as an ocean, river, or stream, and can rotate the turbine. A hydroelectric power system can then use a generator (or permanent magnet generator) to convert the kinetic energy of the turbine's rotation into electrical energy, generating electricity.

[0004] The background technology described above is something that the inventor possessed or acquired in the process of deriving the disclosure of the present application, and cannot necessarily be said to be a publicly known technology disclosed to the general public prior to the present application.

[0005] Hydroelectric power systems require turbine diameter, number of turbine blades, blade engagement angle, and flow path design based on water flow characteristics such as head and flow rate. Consequently, individual manufacturing of turbines and other components was required, limiting the versatility of the device.

[0006] In addition, the hydroelectric power generation system using a generator (or permanent magnet generator) had a limited range of AC power frequency and voltage, so there was a limit to the number of rotations per unit time of the turbine, and if the number of rotations exceeded the limited range, the rotation of the turbine had to be stopped by applying a reverse current to the generator. However, there was a loss of power due to the reverse current, and furthermore, a problem occurred in which the turbine rotated in reverse due to the reverse current, consuming current instead of generating electricity.

[0007] The purpose of the various embodiments of this document is to provide a hydroelectric power generation system and its design method that address the aforementioned issues. However, the purpose of the hydroelectric power generation system and its design method according to the various embodiments of this document is not limited thereto.

[0008] According to one embodiment, a design method of a hydroelectric power generation system may include the steps of: determining an initial head and an initial flow rate of a water flow; inputting the initial head and the initial flow rate into a turbine model that calculates a rotational speed of a turbine from the head and flow rate of the water flow, including a turbine design factor, to select a target rotational speed of the turbine; calculating a flow rate and a computed rotational speed at the head of the water flow by computational fluid dynamics; comparing the target rotational speed and the computed rotational speed; changing the flow rate if the target rotational speed and the computed rotational speed do not match; determining a final rotational speed of the turbine as a matching value if the target rotational speed and the computed rotational speed match; and calculating an output of the hydroelectric power generation system from the final rotational speed to calculate a power generation output. In one embodiment, after the step of changing the flow rate, the step of resetting the target rotational speed by inputting the changed flow rate into the water wheel model, recalculating the computed rotational speed according to the changed flow rate, and comparing the target rotational speed and the computed rotational speed may be returned to the step.

[0009] In one embodiment, the step of selecting the target rotational speed of the turbine may further include the step of calculating a frictional loss occurring when the turbine rotates due to the water flow, the step of calculating an unrestrained speed of the turbine due to the water flow, the step of calculating an expected rotational speed of the turbine from the frictional loss and the unrestrained speed, and the step of comparing the expected rotational speed with the target rotational speed.

[0010] In one embodiment, the step of selecting the target rotational speed of the turbine may further include, after the step of comparing the expected rotational speed with the target rotational speed, a step of changing the target rotational speed by changing the design factor if the expected rotational speed and the target rotational speed do not match, and a step of determining the design factor if the expected rotational speed and the target rotational speed match.

[0011] In one embodiment, the step of selecting the target rotational speed of the turbine may return to the step of changing the design factor based on the changed target rotational speed after the step of changing the target rotational speed, and comparing the expected rotational speed with the target rotational speed.

[0012] In one embodiment, after the step of calculating the power generation output, the step of calculating the initial frequency and voltage of the AC electricity generated according to the final rotation speed may be further included.

[0013] In one embodiment, after the step of calculating the initial frequency and voltage, the step of converting the AC electricity into DC electricity may be included; and the step of converting the DC electricity back into AC electricity having a target frequency and voltage may be included.

[0014] A hydroelectric power generation system and its design method according to one embodiment can accurately predict the rotational speed of a turbine according to the characteristics of the water flow when using a permanent magnet generator whose rotational speed varies proportionally depending on the size of the water flow (head or flow rate). Accordingly, the hydroelectric power generation system can calculate the power generation output based on the rotational speed of the turbine to generate AC electricity of an appropriate frequency, and can be operated according to various water flow characteristics, thereby providing the versatility of the hydroelectric power generation system.

[0015] A hydroelectric power generation system and its design method according to one embodiment can convert the frequency of alternating current power to set a wider range of rotational speed per unit time of a turbine and overcome limitations caused by conventional reverse current.

[0016] The effects of the hydroelectric power generation system and its design method according to one embodiment are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

[0017] The following drawings attached to this specification illustrate a preferred embodiment of the present invention and, together with the detailed description of the invention, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0018] Figure 1 is a schematic diagram of a hydroelectric power generation system according to one embodiment.

[0019] Figure 2 is a perspective view of a hydroelectric power plant according to one embodiment.

[0020] Figure 3 is a flowchart of a design method of a hydroelectric power generation system according to one embodiment.

[0021] Figure 4 is an estimated graph for predicting the number of revolutions per unit time of a turbine for a flow rate.

[0022] Hereinafter, embodiments are described in detail with reference to the attached drawings. However, the embodiments may be modified in various ways, and the scope of the invention is not limited or restricted by these embodiments. It should be understood that all modifications, equivalents, or alternatives to the embodiments are included within the scope of the invention.

[0023] The terms used in the examples are for illustrative purposes only and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but should be understood to not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0024] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiments pertain. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0025] In addition, when describing with reference to the attached drawings, identical components will be assigned the same reference numerals regardless of the drawing numbers, and redundant descriptions thereof will be omitted. When describing embodiments, if a detailed description of a related known technology is judged to unnecessarily obscure the gist of the embodiment, the detailed description will be omitted.

[0026] Additionally, terms such as first, second, A, B, (a), (b), etc. may be used to describe components of the embodiments. These terms are only intended to distinguish the components from other components, and the nature, order, or sequence of the components are not limited by the terms. When it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the component may be directly connected or connected to the other component, but another component may also be "connected," "coupled," or "connected" between each component.

[0027] Components included in one embodiment and components with common functions will be described using the same names in other embodiments. Unless otherwise stated, the descriptions given in one embodiment may also apply to other embodiments, and detailed descriptions will be omitted to the extent of overlap.

[0028] FIG. 1 is a schematic diagram of a hydroelectric power generation system (10) according to one embodiment, and FIG. 2 is a perspective view of a hydroelectric power generation device (100) according to one embodiment.

[0029] Referring to FIGS. 1 and 2, a hydroelectric power generation system (10) according to one embodiment may include at least some of a turbine (103), a power generation unit (110), a processor (150), and a memory (155).

[0030] In one embodiment, a hydroelectric power generation system (10) can generate electricity by means of a fluid flow (hereinafter referred to as “fluid flow”). The hydroelectric power generation system (10) can be installed in a water channel (25) through which fluid flows from an upstream water channel (11) to a lower water channel (15).

[0031] In one embodiment, the hydroelectric power generation system (10) may refer to a hydroelectric power generation device (100) installed in a waterway (25). Alternatively, the hydroelectric power generation system (10) may further include, in addition to the hydroelectric power generation device (100), a sluice gate (or valve) (20) for controlling water flow, a sensor unit (not shown) for checking the status of the upstream waterway (11), the downstream waterway (15), and the waterway (25), or a communication device (not shown) for communicating with the outside.

[0032] In one embodiment, a hydroelectric power generation device (100) may be installed in a water channel (25). The hydroelectric power generation device (100) may include a housing (101) and a flow path (102). The housing (101) may form the exterior of the hydroelectric power generation device (100), and the electrical components of the hydroelectric power generation system (10) may be accommodated inside the housing (101). A turbine (103) may be installed in the flow path (102).

[0033] In one embodiment, the turbine (103) may include turbine blades and a rotor. The turbine blades may be rotated by a water flow. The turbine blades may be formed in multiples and surround the outer periphery of the turbine (103). The rotor may be rotated by the turbine blades. The rotor may include permanent magnets.

[0034] In one embodiment, the power generation unit (110) can generate power by the rotation of the turbine (103). The power generation unit (110) can include a stator. The stator can electrically interact with the rotor. The rotor can rotate about its axis of rotation, and the stator can be fixed and separated from the rotor.

[0035] In one embodiment, the power generation unit (110) includes a coil surrounding a stator, and the coil can generate power by electromagnetically interacting with a permanent magnet of the rotor. For example, as the rotor rotates, the permanent magnet rotates, and the coil wound around the stator electromagnetically interacts with the permanent magnet, so that a current can flow within the coil.

[0036] In one embodiment, each of the converter (120) and the inverter (130) can convert power generated by the power generation unit (110). For example, the converter (120) can convert alternating current electricity generated by the power generation unit (110) into direct current electricity. The inverter (130) can convert the direct current electricity converted by the converter (120) back into alternating current electricity.

[0037] In one embodiment, the converter (120) and the inverter (130) can convert AC electricity having an arbitrary frequency generated by the power generation unit (110) to have a frequency suitable for sending to an external power receiver (50). The inverter (130) can convert the DC electricity converted by the converter (120) into AC electricity, thereby converting the DC electricity into AC electricity having a target frequency.

[0038] In one embodiment, the distribution panel (140) may be branched from inside the hydroelectric power generation system (10) to outside. For example, power generated in the hydroelectric power generation system (10) may be transmitted to an external power receiving source (50).

[0039] In one embodiment, the processor (150) can control the operation of the hydroelectric power generation system (10). For example, the processor (150) can control the operation of at least some of the sluice gate (or valve) (20), the power generation unit (110), the converter (120), the inverter (130), and the distribution panel (140).

[0040] In one embodiment, the processor (150) may be coupled to a memory. The memory may be operatively coupled to the processor (150) and may store executable instructions.

[0041] For example, the processor (150) may call and execute at least one command among one or more commands stored from a storage medium such as memory. Accordingly, the processor (150) enables the device to operate to perform at least one function according to the command. The one or more commands may include code generated by a compiler or code executable by an interpreter.

[0042] In one embodiment, the monitoring unit (160) can monitor the operating status of the hydroelectric power generation system (10). The monitoring unit (160) can provide the monitoring results to the processor (150). The processor (150) can control the operation of the hydroelectric power generation system (10) based on the monitoring results.

[0043] Hereinafter, a design method (500) of a hydroelectric power generation system (10) by a processor (150) will be described with reference to the components of the hydroelectric power generation system (10) described above. However, the control target of the design method (500) of the hydroelectric power generation system (10) is not limited to the hydroelectric power generation system (10) described above.

[0044] In one embodiment, the design method (500) may be implemented as software (e.g., a program) including one or more instructions stored in a storage medium (e.g., memory) readable by a user, designer, or device.

[0045] For example, the design method (500) may be provided as a computer program product. The computer program product may be traded between sellers and buyers as a product.

[0046] In one embodiment, one or more components or steps of the components may be omitted, or one or more other components or steps may be added. Alternatively or additionally, multiple components (e.g., modules or programs) may be integrated into a single component. In this case, the integrated component may perform one or more functions of each of the multiple components identically or similarly to those performed by the corresponding component of the multiple components prior to integration.

[0047] In one embodiment, the actions or steps performed by a module, program, designer or other component may be performed sequentially, in parallel, iteratively, or heuristically, or one or more of the steps may be performed in a different order, omitted, or one or more other steps may be added.

[0048] FIG. 3 is a flowchart of a design method (500) of a hydroelectric power generation system (10) according to one embodiment, and FIG. 4 is an estimation graph for predicting the number of rotations per unit time of a turbine (103) for a flow rate.

[0049] In one embodiment, the step of determining the initial head and initial flow rate (510) may determine the initial conditions of the water flow provided to the hydroelectric power generation system (10) by taking into account the conditions of the water channel (25) in which the hydroelectric power generation system (10) is installed and the characteristics of the water flow. The initial head and initial flow rate may be determined empirically, measured, or calculated.

[0050] In one embodiment, the water model determination step (515) may design or determine the water model by considering the initial drop and initial flow rate of the determination step (510).

[0051] In one embodiment, the target rotational speed selection step (520) may select the target rotational speed of the turbine (103) by inputting the initial head and initial flow rate into a turbine model that calculates the rotational speed of the turbine (103) from the head and flow rate of the water flow, including the turbine design factors. The target rotational speed by the initial head and initial flow rate may be modified as an initial value through a feedback process described later.

[0052] In one embodiment, the turbine model may be a model that calculates the number of rotations per unit time of the turbine (103) according to empirically modeled water flow conditions. The turbine model may be set, changed, or supplemented by the implementer of the design method (500) or through communication, and is not limited to a specific equation or calculation model.

[0053] In one embodiment, the computational rotational speed calculation step (530) may calculate the computational rotational speed of the turbine (103) according to the head and flow rate of the water flow by computational fluid dynamics. Computational fluid dynamics may mean equations that simulate the movement and effects of fluids and mathematically express them.

[0054] For example, the governing equations of computational fluid dynamics (CFD) are the Navier-Stokes equations. Because their solutions are not readily available, solutions can be obtained by limiting certain conditions or making certain assumptions. However, these CFD methods can incur errors due to the aforementioned conditions and assumptions. Therefore, the error range can be reduced by referencing results from other methods.

[0055] In one embodiment, the step (540) of comparing the target rotation speed and the computed rotation speed may be a part of a feedback step of finding the final rotation speed by changing the flow conditions of the water flow by comparing the computed result value and the result value by the water wheel model.

[0056] In one embodiment, the flow rate change step (543) may change the initial flow rate or the flow rate if the target rotation speed and the computed rotation speed do not match. The flow rate change step (543) may change the flow rate and return to the target rotation speed selection step (520).

[0057] For example, the target rotational speed selection step (520) after the flow rate change step (543) can input the changed flow rate into the water turbine model to reset the target rotational speed, and the computed rotational speed calculation step (530) can then recalculate the computed rotational speed according to the changed flow rate. Then, based on the reset target rotational speed and computed rotational speed, the process returns to the step (540) of comparing the target rotational speed and the computed rotational speed to determine whether the target rotational speed and the computed rotational speed match. If the target rotational speed and the computed rotational speed do not match, the flow rate change step (543) can be performed again, and the above-described steps can be repeated. These repeating steps can be performed until the target rotational speed and the computed rotational speed match.

[0058] In one embodiment, the final rotation speed determination step (545) can determine the final rotation speed of the turbine (103) as a matching value if the target rotation speed and the computed rotation speed match.

[0059] For example, in FIG. 4, L1 is a line that virtually depicts the number of rotations per unit time of the turbine (103) according to the flow rate by the water turbine model, and L2 is a line that virtually depicts the number of rotations per unit time of the turbine (103) according to the flow rate by computational fluid dynamics. As shown in the drawing, even if L1 and L2 may have similar tendencies, the expected number of rotations for the same flow rate may be different.

[0060] In one embodiment, the intersection point (A) of L1 and L2 may be the actual operating point. That is, the intersection point (A) may be the final rotational speed per unit time of the turbine (103).

[0061] A design method (500) according to one embodiment of this document can derive an initial result value through a water model having water design factors, and compare it with a computational result value of computational fluid dynamics to derive a final result value that minimizes the error range.

[0062] In one embodiment, the turbine efficiency / power calculation step (549) can calculate the turbine efficiency and power output of the hydroelectric power generation system (10) from the final rotational speed. The power generation output calculation step (550) can calculate the power generation output of the hydroelectric power generation system (10) based on the turbine efficiency and power output. The hydroelectric power generation system (10) can design the drive and operation of the power generation system based on the calculated power generation output.

[0063] In one embodiment of this document, the design method (500) can be universally used in various installation environments by calculating and driving the power generation output of a hydroelectric power generation system (10).

[0064] In one embodiment, the step (520) of selecting a target rotational speed of the turbine (103) may include multiple steps for calculating a specific turbine model.

[0065] In one embodiment, the friction loss calculation step (521) can calculate the friction loss that occurs when the turbine (103) rotates due to the water flow. The unrestrained speed calculation step (522) can calculate the unrestrained speed of the turbine (103) due to the water flow. The expected rotational speed calculation step (523) can calculate the expected rotational speed of the turbine (103) from the friction loss and the unrestrained speed.

[0066] In one embodiment, after the step (520) of selecting the target rotation speed of the turbine (103), a step (524) of comparing the expected rotation speed with the target rotation speed may be performed.

[0067] The step (524) of comparing the expected rotation speed with the target rotation speed may be a part of a feedback step of finding design factors suitable for the environment in which the hydroelectric power generation system (10) is installed by changing the target rotation speed and design factors.

[0068] In one embodiment, the target rotation speed changing step (526) and the design factor changing step (526) may change the target rotation speed and the design factor if the expected rotation speed and the target rotation speed do not match after the step (524) of comparing the expected rotation speed and the target rotation speed. The target rotation speed changing step (526) and the design factor changing step (526) may change the target rotation speed and the design factor and return to the friction loss calculation step (521).

[0069] For example, the friction loss calculation step (521) and the free speed calculation step (522) following the target rotation speed change step (526) and the design factor change step (526) can recalculate the friction loss and free speed based on the changed target rotation speed. In addition, the expected rotation speed calculation step (523) can recalculate the expected rotation speed based on the recalculated friction loss and free speed.

[0070] In one embodiment, the step (420) of selecting the target rotation speed of the turbine (103) may return to the step (524) of comparing the recalculated predicted rotation speed with the target rotation speed and the predicted rotation speed to determine whether the target rotation speed and the predicted rotation speed match. If the target rotation speed and the predicted rotation speed do not match, the step (526) of changing the target rotation speed and the step (526) of changing the design factors may be performed again, thereby repeating the above-described steps. These repeating steps may be performed until the target rotation speed and the predicted rotation speed match.

[0071] In one embodiment, the design factor determination step (527) can determine the design factor if the expected rotational speed and the target rotational speed match. Accordingly, the design method (500) can establish a turbine model having design factors that take into account environmental factors in which the hydroelectric power generation system (10) is installed.

[0072] Although the embodiments described above have been described with limited drawings, those skilled in the art will appreciate that various technical modifications and variations can be applied based on the above. For example, appropriate results can still be achieved even if the described techniques are performed in a different order than described, and / or components of the described systems, structures, devices, circuits, etc. are combined or combined in a different manner than described, or are replaced or substituted with other components or equivalents.

[0073] Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the claims set forth below.

Claims

1. In the design method of a hydroelectric power generation system, A step of determining the initial head and initial flow rate of the water stream; A step of selecting a target rotational speed of the turbine by inputting the initial head and the initial flow rate into a turbine model that calculates the rotational speed of the turbine from the head and flow rate of the water flow including the turbine design factors; A step of calculating the computational rotational speed of the turbine according to the head and flow rate of the water flow by computational fluid dynamics; A step of comparing the target rotation speed and the computed rotation speed; A step of changing the flow rate when the target rotation speed and the computed rotation speed do not match; If the target rotation speed and the computed rotation speed match, a step of determining the final rotation speed of the turbine as the matching value; and Comprising a step of calculating the power generation output by calculating the output of the hydroelectric power generation system from the final rotational speed, After the step of changing the above flow rate, A design method for a hydroelectric power generation system, wherein the method returns to the step of inputting the changed flow rate into the water turbine model to reset the target rotational speed, recalculating the computed rotational speed according to the changed flow rate, and comparing the target rotational speed and the computed rotational speed.

2. In paragraph 1, After the step of selecting the target rotation speed of the turbine, A step of calculating the friction loss that occurs when the turbine rotates due to the water flow; A step of calculating the unrestrained speed of the turbine by the above water flow; A step of calculating the expected rotational speed of the turbine from the friction loss and the unrestrained speed; and A design method of a hydroelectric power generation system, further comprising a step of comparing the expected rotational speed with the target rotational speed.

3. In paragraph 2, The step of selecting the target rotational speed of the above turbine is: After the step of comparing the above expected rotation speed and the above target rotation speed, If the expected rotation speed and the target rotation speed do not match, a step of changing the design factor to change the target rotation speed; and A design method for a hydroelectric power generation system, further comprising a step of determining the design factor if the expected rotational speed and the target rotational speed match.

4. In paragraph 3, The step of selecting the target rotational speed of the above turbine is: A design method for a hydroelectric power generation system, wherein after the step of changing the target rotational speed, the design factor is changed based on the changed target rotational speed, and the method returns to the step of comparing the expected rotational speed with the target rotational speed.

5. In paragraph 1, After the step of calculating the above development output, A design method of a hydroelectric power generation system, further comprising the step of calculating the initial frequency and voltage of the AC electricity generated according to the final rotational speed.

6. In paragraph 5, After the step of calculating the initial frequency above, A step of converting the above AC electricity into DC electricity; and A method for designing a hydroelectric power generation system, comprising the step of reconverting the direct current into alternating current having a target frequency.

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