Tidal current energy power generation load working condition self-adaptive operation control method

Abstract

The invention provides a tidal current energy power generation load working condition self-adaptive operation control method which comprises the following steps: when a tidal current flow rate is increased and a fixed-pitch propeller generator set meets an adjustment condition, adjusting a current control mode according to the following strategy; specifically, when the current control mode is a torque mode, the next control mode is a rated rotating speed mode, when the current control mode is the rated rotating speed mode, the next control mode is a low rated rotating speed mode, and when the current control mode is the low rated rotating speed mode, the next control mode is a shutdown mode; when the tidal current flow velocity is reduced and the fixed-pitch propeller generator set meets the adjusting condition, the current control mode is adjusted according to the following strategy; specifically, when the current control mode is the torque mode, the next control mode is the shutdown mode, when the current control mode is the rated rotation speed mode, the next control mode is the torque mode, and when the current control mode is the low rated rotation speed mode, the next control mode is the rated rotation speed mode. The operation safety of the generator set is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of ocean energy power generation, and in particular to a load condition adaptive operation control method for tidal energy power generation. Background Art

[0002] Tidal energy is a type of ocean energy that uses the energy of water flow generated by the ebb and flow of the tide to generate electricity. It is a green and clean energy source. During the ebb and flow of the tide, the flow velocity of a tidal segment gradually increases to a maximum value, then decreases to a minimum value. The tide then turns, and the flow velocity repeats this process of increasing and then decreasing. The direction of the tidal flow is opposite to that of the ebb and flow, but theoretically, the direction of the tidal flow is consistent within the same tidal segment.

[0003] Since my country's tidal energy-rich sea areas are located near the coast and have complex underwater terrain, in open waters, due to the mutual interference of waterways, the actual tidal flow conditions faced by tidal energy generators are very different from the theoretical ones. At certain critical points, the flow rate will fluctuate repeatedly. In a short period of time, the flow rate of the tide will suddenly increase or decrease, or suddenly increase and suddenly decrease, suddenly decrease or suddenly increase due to flow interference and turbulence. For generators with fixed-pitch propellers, the pitch is fixed and the unloading capacity is relatively weak. When its control mode is only a single mode, the control strategy will not be able to follow up and match the processing in time, and abnormal conditions such as overpower, overspeed, excessive vibration, and passive disconnection will occur, causing the unit to shut down or fail, greatly increasing the unit's failure time and maintenance costs.

[0004] Therefore, it is urgent to provide an adaptive operation control method for tidal energy power generation load conditions. By adding control modes and setting switching strategies between control modes, the method solves the safety problems caused by repeated changes in tidal energy or sudden load changes caused by sudden increases and decreases during operation of fixed-pitch propeller units, as well as the safety problems caused by overspeed and overload, or shutdown problems caused by the need for emergency shutdown, thereby avoiding unit failures and reducing the unit's failure time and maintenance costs. Summary of the Invention

[0005] In view of this, it is necessary to provide a tidal energy power generation load condition adaptive operation control method to solve the technical problem that the control mode of the fixed-pitch propeller generator set in the prior art is single, which leads to abnormal conditions such as overpower, overspeed, and excessive vibration during the operation of the fixed-pitch propeller generator set, resulting in unit failure, and further increasing the unit's failure time and maintenance cost.

[0006] The present invention provides a method for adaptively controlling operation of a tidal energy power generation load condition, which is used to control the control mode of a fixed-pitch propeller generator set when encountering tidal energy during operation. The control modes include a torque mode, a rated speed mode, a low-rated speed mode, and a shutdown mode. The speeds of the torque mode, the rated speed mode, and the low-rated speed mode decrease in sequence. The method comprises: When the tidal flow velocity increases, resulting in an increase in load, the power and / or speed of the fixed-pitch propeller generator set is obtained, and when the power and / or speed exceeds a first set value and the duration of the excess is greater than the first duration, the current control mode is adjusted to the next control mode according to a first preset adjustment strategy; the first preset adjustment strategy is: when the current control mode is the torque mode, the next control mode is the rated speed mode, when the current control mode is the rated speed mode, the next control mode is the low rated speed mode, and when the current control mode is the low rated speed mode, the next control mode is the shutdown mode; When the tidal flow velocity decreases, resulting in a decrease in load, the power and / or speed of the fixed-pitch propeller generator set is obtained. When the power and / or speed is less than a second set value, and the time length is greater than the second time length, the current control mode is adjusted to the next control mode according to the second preset adjustment strategy; the second preset adjustment strategy is: when the current control mode is the torque mode, the next control mode is the shutdown mode, when the current control mode is the rated speed mode, the next control mode is the torque mode, and when the current control mode is the low rated speed mode, the next control mode is the rated speed mode.

[0007] In some possible implementations, the first duration includes a first increase duration, a second increase duration, and a third increase duration. When the tidal flow velocity increases, resulting in an increase in load, the power and / or speed of the fixed-pitch propeller generator set is obtained. When the power and / or speed exceeds a first set value and the duration of the excess is greater than the first duration, the current control mode is adjusted to the next control mode using a first preset adjustment strategy, including: When the current control mode is the torque mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and / or the speed is greater than the first speed setting value, and the time period for which the power is greater than the first power setting value and / or the speed is greater than the first speed setting value is greater than the first increase time period, the current control mode is adjusted to the rated speed mode; When the current control mode is the rated speed mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and greater than the second power setting value, and the time duration for which the power is greater than the second power setting value is greater than the second increased time duration, the current control mode is adjusted to the low rated speed mode; When the current control mode is the low rated speed mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and greater than the third power setting value, and the time duration for which the power is greater than the third power setting value is greater than the third increased time duration, the current control mode is adjusted to the shutdown mode.

[0008] In some possible implementations, the method further includes: When the tidal flow velocity increases, resulting in an increase in load, it is determined whether the power of the fixed-pitch propeller generator set exceeds the maximum power upper limit and whether the time period for exceeding the maximum power upper limit is greater than the first limit time period. If so, the current control mode is adjusted to a low rated speed mode, and the current control mode is a torque mode or a rated speed mode.

[0009] In some possible implementations, the first power setting value and the second power setting value are 1.02-1.08 times the rated power, the first speed setting value is 1.02-1.08 times the rated speed, the third power setting value is 1.09-1.11 times the rated power, and the limit power upper limit is 1.1-1.2 times the rated power; The first increase duration and the second increase duration are 3S-7S, the third increase duration is 9S-11S, and the first limit duration is 1.5S-2.5S.

[0010] In some possible implementations, the second duration includes a first reduction duration, a second reduction duration, and a third reduction duration. When the tidal flow velocity decreases, resulting in a load reduction, the power and / or speed of the fixed-pitch propeller generator set is obtained. When the power and / or speed is less than a second set value and the duration is less than or equal to the second duration, the current control mode is adjusted to the next control mode using a second preset adjustment strategy, including: When the current control mode is the torque mode, and the power of the fixed-pitch propeller generator set is less than a fourth power setting value, and the duration for which the power is less than the fourth power setting value is greater than the first reduction duration, the current control mode is adjusted to the shutdown mode; When the current control mode is the rated speed mode, and the power of the fixed-pitch propeller generator set is less than the fifth power setting value, and the time duration for which the power is less than the fifth power setting value is greater than the second reduction time duration, the current control mode is adjusted to the torque mode; When the current control mode is the low rated speed mode, and the power of the fixed-pitch propeller generator set is less than the sixth power setting value, and the time when the power is less than the sixth power setting value is greater than the third reduction time, the current control mode is adjusted to the rated speed mode.

[0011] In some possible implementations, the method further includes: When the tidal flow velocity decreases, resulting in a decrease in load, it is determined whether the power of the fixed-pitch propeller generator set is less than the lower limit of the power limit and whether the time period less than the lower limit of the power limit is greater than the second limit time period. If so, the current control mode is adjusted to the torque mode, and the current control mode is the low rated speed mode or the rated speed mode.

[0012] In some possible implementations, the fourth power setting value and the fifth power setting value are 0.75-0.85 times the rated power, the sixth power setting value is 0.9-0.95 times the rated power, and the lower limit of the extreme power is 0.65-0.7 times the rated power; The first reduction time length, the second reduction time length and the third reduction time length are 3S-7S, and the second limit time length is 2.5S-3.5S.

[0013] In some possible implementations, before executing the first preset adjustment strategy or the second preset adjustment strategy, the control mode allocation strategy is: When the power of the fixed-pitch propeller generator set is less than the rated power, determining that the control mode is the torque mode; When the power of the fixed-pitch propeller generator set is greater than the power setting value, determining that the control mode is the low rated speed mode, and the power setting value is a preset multiple of the rated power; When the power of the fixed-pitch propeller generator set is greater than or equal to the rated power and less than or equal to the power setting value, the control mode is determined to be the rated speed mode.

[0014] In some possible implementations, the control mode further includes an ultra-low rated speed mode, and the speed of the ultra-low rated speed mode is lower than the speed of the low rated speed mode. In this case, the first preset adjustment strategy is: When the current control mode is torque mode, the next control mode is rated speed mode; when the current control mode is rated speed mode, the next control mode is low rated speed mode; when the current control mode is low rated speed mode, the next control mode is ultra-low rated speed mode; when the current control mode is ultra-low rated speed mode, the next control mode is shutdown mode.

[0015] In some possible implementations, the second preset adjustment strategy is: When the current control mode is torque mode, the next control mode is shutdown mode; when the current control mode is rated speed mode, the next control mode is torque mode; when the current control mode is low rated speed mode, the next control mode is rated speed mode; when the current control mode is ultra-low rated speed mode, the next control mode is low rated speed mode.

[0016] The beneficial effect of adopting the above-mentioned implementation method is: the adaptive operation control method for tidal energy power generation load conditions provided by the present invention introduces three control modes in non-shutdown states, namely torque mode, rated speed mode, and low rated speed mode. It can switch between multiple control modes based on power and / or speed, so that the switched control mode matches the actual scenario of sudden increase or decrease in tidal current, that is: the control strategy can follow the actual scenario in time to avoid generator set failures caused by overpower, overspeed, etc., significantly reduce the failure time and maintenance cost of the set, and improve the operation safety of the fixed-pitch propeller generator set. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 A schematic flow chart of an embodiment of the method for adaptively controlling the load condition of tidal energy generation provided by the present invention; Figure 2 A flow chart of another embodiment of the method for adaptively controlling the load conditions of tidal energy generation provided by the present invention. DETAILED DESCRIPTION

[0019] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0020] It should be understood that the schematic drawings are not drawn to scale. The flowcharts used in the present invention illustrate operations implemented according to some embodiments of the present invention. It should be understood that the operations of the flowcharts can be implemented out of sequence, and steps that have no logical contextual relationship can be reversed in order or implemented simultaneously. In addition, those skilled in the art, guided by the content of the present invention, can add one or more other operations to the flowcharts or remove one or more operations from the flowcharts. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different networks and / or processor systems and / or microcontroller systems.

[0021] The terms "first" and "second" in the embodiments of the present invention are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a technical feature designated as "first" or "second" may explicitly or implicitly include at least one such feature.

[0022] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0023] The present invention provides an adaptive operation control method for tidal energy power generation load conditions, which is used to control the control mode of a fixed-pitch propeller generator set when it encounters tidal energy during operation, wherein the control modes include a torque mode, a rated speed mode, a low rated speed mode and a shutdown mode. Specifically, the speed of the torque mode, the speed of the rated speed mode and the speed of the low rated speed mode decrease in sequence.

[0024] It should be noted that torque mode refers to controlling the speed and power of the generator set based on a pre-set power and speed curve. Rated speed mode controls the generator set to operate at a fixed rated speed. Underrated speed mode controls the generator set to operate at a speed lower than the rated speed.

[0025] In some embodiments of the present invention, the method for adaptively controlling operation of tidal energy generation load conditions includes: When the tidal flow velocity increases, resulting in an increase in load, the power and / or speed of the fixed-pitch propeller generator set is obtained. When the power and / or speed exceeds a first set value and the duration of the excess is greater than the first duration, the current control mode is adjusted to the next control mode using a first preset adjustment strategy; the first preset adjustment strategy is: when the current control mode is the torque mode, the next control mode is the rated speed mode; when the current control mode is the rated speed mode, the next control mode is the low rated speed mode; when the current control mode is the low rated speed mode, the next control mode is the shutdown mode; When the tidal flow velocity decreases, resulting in a decrease in load, the power and / or speed of the fixed-pitch propeller generator set is obtained. When the power and / or speed is less than the second set value, and the time length is greater than the second time length, the current control mode is adjusted to the next control mode according to the second preset adjustment strategy; the second preset adjustment strategy is: when the current control mode is the torque mode, the next control mode is the shutdown mode, when the current control mode is the rated speed mode, the next control mode is the torque mode, and when the current control mode is the low rated speed mode, the next control mode is the rated speed mode.

[0026] Specifically, the first setting value is greater than the second setting value.

[0027] Among them, the above-mentioned entire control steps are controlled by PLC program, and the duration and set value can be set or adjusted according to the actual application scenario, and can be modified and optimized according to the operating conditions.

[0028] It should be noted that: when the tidal flow velocity increases, the power and the speed may be the maximum power and the maximum speed, and when the tidal flow velocity decreases, the power and the speed may be the minimum power and the minimum speed.

[0029] It should also be noted that: in order to improve the safety of the generator set during the adjustment process, when the speed or power is greater than the first set value and the exceeding time is greater than the first time, the inverter is first used to apply reverse torque to stop the generator, and then the mechanical brake is applied. If the inverter fails, the generator is directly stopped by the mechanical brake to avoid dangerous situations.

[0030] It should be understood that the tidal energy power generation load condition adaptive operation control method in the embodiments of the present invention can be implemented in any device based on the tidal energy power generation load condition adaptive operation control method, such as a generator set control device. Specifically, the tidal energy power generation load condition adaptive operation control method is stored in the aforementioned device in the form of a pre-programmed program. When the device is started, the program is called and the tidal energy power generation load condition adaptive operation control method is implemented.

[0031] Compared with the prior art, the embodiment of the present invention provides an adaptive operation control method for tidal energy power generation load conditions, which introduces three control modes in non-shutdown states: torque mode, rated speed mode, and low rated speed mode. It can switch between multiple control modes based on power and / or speed, so that the switched control mode matches the actual scenario of sudden increase or decrease in tidal current, that is, the control strategy can keep up with the actual scenario in a timely manner, avoiding generator set failures caused by overpower, overspeed, etc., significantly reducing the failure time and maintenance cost of the set, and improving the operation safety of the fixed-pitch propeller generator set.

[0032] In some embodiments of the present invention, the first duration includes a first increased duration, a second increased duration, and a third increased duration. Figure 1 As shown, the first preset adjustment strategy when the tidal flow velocity increases and the load increases is specifically: When the current control mode is the torque mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and / or the speed is greater than the first speed setting value, and the time when the power is greater than the first power setting value and / or the speed is greater than the first speed setting value is greater than the first increase time, the current control mode is adjusted to the rated speed mode.

[0033] Among them, power and / or speed refers to power, speed, and power and speed. In other words, when at least one of the power or speed exceeds the first power setting value and the first speed setting value, the condition for adjusting the current control mode from the speed mode to the rated speed mode is met.

[0034] When the current control mode is the rated speed mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and greater than the second power setting value, and the time duration for which the power is greater than the second power setting value is greater than the second increased time duration, the current control mode is adjusted to the low rated speed mode; When the current control mode is the low rated speed mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and greater than the third power setting value, and the time when the power is greater than the third power setting value is greater than the third increased time, the current control mode is adjusted to the shutdown mode.

[0035] The embodiment of the present invention can avoid overload by adjusting the current control mode to the next control mode with lower speed as the power and / or speed increase, thereby ensuring that the generator set does not overspeed or overload.

[0036] In some embodiments of the present invention, the first power setting value and the second power setting value are 1.02-1.08 times the rated power, the first speed setting value is 1.02-1.08 times the rated speed, and the third power setting value is 1.09-1.11 times the rated power; the first increase time and the second increase time are 3S-7S, and the third increase time is 9S-11S.

[0037] In a specific embodiment of the present invention, the first power setting value and the second power setting value are 1.05 times the rated power, the first speed setting value is 1.05 times the rated speed, the third power setting value is 1.01 times the rated power, the first increase time and the second increase time are 5S, and the third increase time is 10S.

[0038] The embodiment of the present invention can optimize the adjustment timing by setting specific adjustment conditions for mode adjustment / switching, avoid the adverse effects caused by drastic changes in the unit's speed and power due to too fast switching, and avoid the problem that the unit's speed and power will immediately overload when the switching is not timely, thereby triggering an emergency shutdown, and realize accurate switching of the control mode.

[0039] In some embodiments of the present invention, the second duration includes a first reduced duration, a second reduced duration, and a third reduced duration. Figure 1 As shown in FIG, when the tidal flow velocity decreases, resulting in a decrease in load, the second preset adjustment strategy is: When the current control mode is the torque mode, and the power of the fixed-pitch propeller generator set is less than the fourth power setting value, and the time duration for which the power is less than the fourth power setting value is greater than the first reduction time duration, the current control mode is adjusted to the shutdown mode; When the current control mode is the rated speed mode, and the power of the fixed-pitch propeller generator set is less than the fifth power setting value, and the time duration for which the power is less than the fifth power setting value is greater than the second reduction time duration, the current control mode is adjusted to the torque mode; When the current control mode is the low rated speed mode, and the power of the fixed-pitch propeller generator set is less than the sixth power setting value, and the time when the power is less than the sixth power setting value is greater than the third reduction time, the current control mode is adjusted to the rated speed mode.

[0040] The embodiment of the present invention adjusts the current control mode to the next control mode with higher speed as the power decreases, thereby avoiding the normal operation of the generator set without shutdown, and further avoiding the maintenance time of the generator set.

[0041] In some embodiments of the present invention, the fourth power setting value and the fifth power setting value are 0.75-0.85 times the rated power, and the sixth power setting value is 0.9-0.95 times the rated power; the first reduction time, the second reduction time and the third reduction time are 3S-7S.

[0042] Specifically, the fourth power setting value and the fifth power setting value are 0.8 times the rated power, and the sixth power setting value is 0.95 times the rated power; the first reduction time length, the second reduction time length, and the third reduction time length are 5S.

[0043] In the actual operation environment of the fixed-pitch propeller generator, there is also a situation where the tidal flow rate suddenly increases or decreases particularly sharply. If the control mode is adjusted by the first preset adjustment strategy and the second preset adjustment strategy at this time, the adjustment force is not enough, and the risk of overload or shutdown will still occur. In order to deal with these two special situations, in some embodiments of the present invention, such as Figure 1 As shown, the tidal energy power generation load condition adaptive operation control method also includes: When the tidal flow velocity increases, resulting in an increase in load, it is determined whether the power of the fixed-pitch propeller generator set exceeds the upper limit of the power limit and whether the duration of exceeding the upper limit of the power limit is greater than the first limit duration. If so, the current control mode is adjusted to the low rated speed mode. The current control mode is the torque mode or the rated speed mode. When the tidal flow velocity decreases, resulting in a decrease in load, it is determined whether the power of the fixed-pitch propeller generator set is less than the lower limit of the power limit and whether the time period less than the lower limit of the power limit is greater than the second limit time period. If so, the current control mode is adjusted to the torque mode, and the current control mode is the low rated speed mode or the rated speed mode.

[0044] The embodiment of the present invention introduces an upper limit power limit and a lower limit power limit to determine whether the load suddenly increases or decreases dramatically. When the load suddenly increases dramatically, the current control mode is directly adjusted to the low rated speed mode. Specifically, the torque mode can be directly adjusted to the low rated speed mode without first converting to the rated speed mode, thereby improving the response speed and load adjustment. Similarly, when the load suddenly decreases dramatically, the current control mode is directly adjusted to the torque mode. Specifically, the low rated speed mode can be directly adjusted to the torque mode without first converting to the rated speed mode. This also improves the response speed of the speed and load, improves the adaptability of the control mode, and further ensures the working safety of the generator set.

[0045] In a specific embodiment of the present invention, the upper limit of the limit power is 1.1-1.2 times the rated power, the first limit time is 1.5S-2.5S, the lower limit of the limit power is 0.65-0.7 times the rated power, and the second limit time is 2.5S-3.5S.

[0046] Specifically, the upper limit of the limit power is 1.1 times the rated power, the first limit time is 2 seconds, the lower limit of the limit power is 0.7 times the rated power, and the second limit time is 3 seconds.

[0047] It should be understood that: when the tidal flow rate and load suddenly increase, suddenly decrease, suddenly decrease and then suddenly increase, or suddenly increase and then suddenly decrease, the process can be switched according to the current mode and power / speed judgment conditions, and the first preset adjustment strategy and the second preset adjustment strategy are followed during switching.

[0048] It should be noted that: in order to further ensure the safety of the generator set, in some embodiments of the present invention, such as Figure 1 As shown, no matter what the current control mode is, when the power, speed or vibration value of the generator set exceeds the safety upper limit, it is directly adjusted to the shutdown mode.

[0049] Since the above processes are all adjusted based on the current control mode, before executing the first preset adjustment strategy or the second preset adjustment strategy, such as Figure 1 As shown in Figure 2, the control mode allocation strategy is: When the power of the fixed-pitch propeller generator set is less than the rated power, the control mode is determined to be the torque mode; When the power of the fixed-pitch propeller generator set is greater than the power setting value, the control mode is determined to be the low rated speed mode, and the power setting value is a preset multiple of the rated power; When the power of the fixed-pitch propeller generator set is greater than or equal to the rated power and less than or equal to the power setting value, the control mode is determined to be the rated speed mode.

[0050] Among them, the preset multiple can be set or adjusted according to the actual application scenario and is not specifically limited here.

[0051] In order to further improve the degree of refinement of the adjustment of the fixed-pitch propeller generator set, in some embodiments of the present invention, such as Figure 2 As shown, the control mode also includes an ultra-low rated speed mode, and the speed of the ultra-low rated speed mode is lower than the speed of the low rated speed mode. The first preset adjustment strategy is: When the current control mode is the torque mode, the next control mode is the rated speed mode; when the current control mode is the rated speed mode, the next control mode is the low rated speed mode; when the current control mode is the low rated speed mode, the next control mode is the ultra-low rated speed mode; when the current control mode is the ultra-low rated speed mode, the next control mode is the shutdown mode; The second preset adjustment strategy is: When the current control mode is torque mode, the next control mode is shutdown mode; when the current control mode is rated speed mode, the next control mode is torque mode; when the current control mode is low rated speed mode, the next control mode is rated speed mode; when the current control mode is ultra-low rated speed mode, the next control mode is low rated speed mode.

[0052] In other words, the introduction of the ultra-low rated speed mode, in addition to the low rated speed mode, allows for lower speeds than the low rated speed mode, allowing for better power reduction. This addresses the issue of overload and shutdowns caused by using the low rated speed mode even when the load increases. Similarly, when the load decreases, the number of mode adjustments is increased, improving the refinement of the adjustments.

[0053] Specifically, the ultra-low rated speed adjustment process is as follows: When the power of the fixed-pitch propeller generator set exceeds the set power (for example, 1.1 times the rated power) and lasts for a period of time (for example, 3 seconds or longer), the low rated speed mode currently in operation is switched to an even lower rated speed mode. This lowers the generator set's operating speed, reduces its power generation, mitigates overload, and further reduces the probability of shutdown. Once the power falls below the set power (for example, 1.05 times the rated power) and lasts for a period of time (for example, 60 seconds or longer), the even lower rated speed mode is switched back to the low rated speed mode.

[0054] In summary, the adaptive operation control method for tidal energy power generation load conditions proposed in the embodiment of the present invention first divides the control modes of the unit during operation into three types according to the main power segment of the unit, namely torque mode, rated speed mode, and low rated speed mode, to match the main working conditions of the unit. Then, by introducing a criterion combination consisting of pre-set adjustable key parameters and duration, when certain conditions are met, the mutual switching of the three control modes is flexibly adjusted according to the actual situation to ensure the normal operation of the unit without shutdown, while ensuring the safety of the unit operation to the greatest extent. Furthermore, the problem of instantaneous load changes is also taken into consideration to further ensure the safety of the generator set operation.

[0055] Those skilled in the art will appreciate that all or part of the process flow of the above-described method embodiment can be implemented by instructing related hardware (such as a processor, controller, etc.) through a computer program, and the computer program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a magnetic disk, an optical disk, a read-only memory, or a random access memory.

[0056] The above is a detailed introduction to the adaptive operation control method for tidal energy power generation load conditions provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A method for adaptive operation control of tidal energy power generation load conditions, characterized in that: The method is used to control a control mode when a fixed-pitch propeller generator set encounters tidal energy during operation, wherein the control modes include a torque mode, a rated speed mode, a low-rated speed mode, and a shutdown mode, wherein the speeds of the torque mode, the rated speed mode, and the low-rated speed mode decrease in sequence; the method comprises: When the tidal flow velocity increases, resulting in an increase in load, the power and / or speed of the fixed-pitch propeller generator set is obtained, and when the power and / or speed exceeds a first set value and the duration of the excess is greater than the first duration, the current control mode is adjusted to the next control mode according to a first preset adjustment strategy; the first preset adjustment strategy is: when the current control mode is the torque mode, the next control mode is the rated speed mode, when the current control mode is the rated speed mode, the next control mode is the low rated speed mode, and when the current control mode is the low rated speed mode, the next control mode is the shutdown mode; When the tidal flow velocity decreases, resulting in a decrease in load, the power and / or speed of the fixed-pitch propeller generator set is obtained. When the power and / or speed is less than a second set value, and the time length is greater than the second time length, the current control mode is adjusted to the next control mode according to the second preset adjustment strategy; the second preset adjustment strategy is: when the current control mode is the torque mode, the next control mode is the shutdown mode, when the current control mode is the rated speed mode, the next control mode is the torque mode, and when the current control mode is the low rated speed mode, the next control mode is the rated speed mode.

2. The method for adaptive operation control of tidal energy power generation load conditions according to claim 1 is characterized in that: The first duration includes a first increase duration, a second increase duration, and a third increase duration. When the tidal flow velocity increases, resulting in an increase in load, the power and / or speed of the fixed-pitch propeller generator set is obtained. When the power and / or speed exceeds a first set value and the exceeding duration is greater than the first duration, the current control mode is adjusted to the next control mode using a first preset adjustment strategy, including: When the current control mode is the torque mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and / or the speed is greater than the first speed setting value, and the time period for which the power is greater than the first power setting value and / or the speed is greater than the first speed setting value is greater than the first increase time period, the current control mode is adjusted to the rated speed mode; When the current control mode is the rated speed mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and greater than the second power setting value, and the time duration for which the power is greater than the second power setting value is greater than the second increased time duration, the current control mode is adjusted to the low rated speed mode; When the current control mode is the low rated speed mode, and the power of the fixed-pitch propeller generator set is greater than the first power setting value and greater than the third power setting value, and the time duration for which the power is greater than the third power setting value is greater than the third increased time duration, the current control mode is adjusted to the shutdown mode.

3. The method for adaptive operation control of tidal energy generation load conditions according to claim 2, characterized in that: The method further comprises: When the tidal flow velocity increases, resulting in an increase in load, it is determined whether the power of the fixed-pitch propeller generator set exceeds the maximum power upper limit and whether the time period for exceeding the maximum power upper limit is greater than the first limit time period. If so, the current control mode is adjusted to a low rated speed mode, and the current control mode is a torque mode or a rated speed mode.

4. The method for adaptive operation control of tidal energy generation load conditions according to claim 3 is characterized in that: The first power setting value and the second power setting value are 1.02-1.08 times the rated power, the first speed setting value is 1.02-1.08 times the rated speed, the third power setting value is 1.09-1.11 times the rated power, and the upper limit of the limit power is 1.1-1.2 times the rated power; The first increase duration and the second increase duration are 3S-7S, the third increase duration is 9S-11S, and the first limit duration is 1.5S-2.5S.

5. The method for adaptive operation control of tidal energy generation load conditions according to claim 1, characterized in that: The second duration includes a first reduction duration, a second reduction duration, and a third reduction duration. When the tidal flow velocity decreases, resulting in a load reduction, the power and / or speed of the fixed-pitch propeller generator set is obtained. When the power and / or speed is less than a second set value and the duration is less than or equal to the second duration, the current control mode is adjusted to the next control mode using a second preset adjustment strategy, including: When the current control mode is the torque mode, and the power of the fixed-pitch propeller generator set is less than a fourth power setting value, and the duration for which the power is less than the fourth power setting value is greater than the first reduction duration, the current control mode is adjusted to the shutdown mode; When the current control mode is the rated speed mode, and the power of the fixed-pitch propeller generator set is less than the fifth power setting value, and the time duration for which the power is less than the fifth power setting value is greater than the second reduction time duration, the current control mode is adjusted to the torque mode; When the current control mode is the low rated speed mode, and the power of the fixed-pitch propeller generator set is less than the sixth power setting value, and the time when the power is less than the sixth power setting value is greater than the third reduction time, the current control mode is adjusted to the rated speed mode.

6. The method for adaptive operation control of tidal energy generation load conditions according to claim 5, characterized in that: The method further comprises: When the tidal flow velocity decreases, resulting in a decrease in load, it is determined whether the power of the fixed-pitch propeller generator set is less than the lower limit of the power limit and whether the time period less than the lower limit of the power limit is greater than the second limit time period. If so, the current control mode is adjusted to the torque mode, and the current control mode is the low rated speed mode or the rated speed mode.

7. The method for adaptive operation control of tidal energy generation load conditions according to claim 6, characterized in that: The fourth power setting value and the fifth power setting value are 0.75-0.85 times the rated power, the sixth power setting value is 0.9-0.95 times the rated power, and the lower limit of the extreme power is 0.65-0.7 times the rated power; The first reduction time length, the second reduction time length and the third reduction time length are 3S-7S, and the second limit time length is 2.5S-3.5S.

8. The method for adaptive operation control of tidal energy generation load conditions according to any one of claims 1 to 7, characterized in that: Before executing the first preset adjustment strategy or the second preset adjustment strategy, the control mode allocation strategy is: When the power of the fixed-pitch propeller generator set is less than the rated power, determining that the control mode is the torque mode; When the power of the fixed-pitch propeller generator set is greater than the power setting value, determining that the control mode is the low rated speed mode, and the power setting value is a preset multiple of the rated power; When the power of the fixed-pitch propeller generator set is greater than or equal to the rated power and less than or equal to the power setting value, the control mode is determined to be the rated speed mode.

9. The method for adaptive operation control of tidal energy generation load conditions according to any one of claims 1 to 7, characterized in that: The control mode further includes an ultra-low rated speed mode, where the speed of the ultra-low rated speed mode is lower than the speed of the low rated speed mode. The first preset adjustment strategy is: When the current control mode is torque mode, the next control mode is rated speed mode; when the current control mode is rated speed mode, the next control mode is low rated speed mode; when the current control mode is low rated speed mode, the next control mode is ultra-low rated speed mode; when the current control mode is ultra-low rated speed mode, the next control mode is shutdown mode.

10. The method for adaptive operation control of tidal energy generation load conditions according to claim 9, characterized in that: The second preset adjustment strategy is: When the current control mode is torque mode, the next control mode is shutdown mode; when the current control mode is rated speed mode, the next control mode is torque mode; when the current control mode is low rated speed mode, the next control mode is rated speed mode; when the current control mode is ultra-low rated speed mode, the next control mode is low rated speed mode.

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