Method and system for controlling voltage of direct current bus of wave power generation and transformation system

Abstract

The invention relates to the technical field of new energy power generation, and discloses a wave power generation and transformation system direct current bus voltage control method and system, and the method comprises the steps: determining a target working mode of a target system in response to a control request for the target system, obtaining the target bus voltage of the target system, and judging whether the target bus voltage is within a preset standard voltage interval or not; if the target bus voltage is not in the preset standard voltage interval, matching a corresponding control strategy according to the target working mode, and performing voltage control on the target system by adopting the control strategy until the target bus voltage is in the preset standard voltage interval; the technical problem of how to accurately control the direct current bus voltage under different working models so as to improve the stability of a wave power generation and transformation system is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of renewable energy power generation, and in particular to a method and system for controlling a DC bus voltage of a wave power generation and transformation system. Background Art

[0002] Wave energy is a renewable energy source with huge reserves and has not yet been fully developed. It has the advantages of high energy density and strong energy storage capacity. With the increasing attention paid to marine resources, the development prospects of wave energy are very broad, and wave energy power generation technology will also usher in greater development space.

[0003] Although the wave power generation device is connected to the power grid, the device platform often floats independently on the sea. Due to the complex natural conditions of the ocean and the changeable weather, people are restricted by wind and wave conditions and cannot often land on the device platform. Therefore, wave energy needs to have the ability to dynamically balance energy. Wave power generation devices are different from wind power generation platforms. They are often equipped with a variety of energy combinations, such as wind power generation, photovoltaic power generation, energy storage systems, etc. Many electrical equipment on the platform are connected and collected through the DC bus. Therefore, the stable control of the DC bus voltage of the wave power generation and transformation system is the key core. The stability of the DC bus voltage directly affects the long-term stable operation of the wave power generation and transformation system and the safety of the equipment.

[0004] At present, the existing technologies of wave power generation devices have deficiencies in safety considerations, and usually only focus on one DC bus voltage control method, lacking consideration of the combination of multiple control methods. Therefore, the DC bus voltage control strategy of wave power generation devices in the past was relatively simple. For example, it only relied on energy storage batteries to maintain the DC bus voltage. This method is difficult to meet the needs of wave power generation devices with multiple complementary energy sources. In this mode, there are many uncontrollable factors, the working mode cannot be switched quickly, and local maintenance often requires an overall power outage, which makes it impossible to provide a stable and continuous power supply to the power grid. Summary of the invention

[0005] The present invention provides a DC bus voltage control method and system for a wave power generation and transformation system, which solves the technical problem of how to achieve accurate control of the DC bus voltage under different working models, thereby improving the stability of the wave power generation and transformation system.

[0006] A first aspect of the present invention provides a method for controlling a DC bus voltage of a wave power generation and transformation system, comprising:

[0007] In response to a control request for a target system, determining a target operating mode of the target system, and acquiring a target bus voltage of the target system;

[0008] Determining whether the target bus voltage is within a preset standard voltage range;

[0009] If the target bus voltage is not within the preset standard voltage range, a corresponding control strategy is matched according to the target operating mode, and the control strategy is used to perform voltage control on the target system until the target bus voltage is within the preset standard voltage range.

[0010] Optionally, the control request includes a voltage control request and a mode switching request, and the responding to the control request for the target system to determine a target operating mode of the target system includes:

[0011] In response to the voltage control request for the target system, determining that the target system is in an operating mode in an operating state;

[0012] Receiving and reading the mode switching request, and determining the switching working mode of the target system;

[0013] comparing the running working mode with the switching working mode;

[0014] If the comparison is consistent, the operating working mode is used as the target working mode;

[0015] If the comparison is inconsistent, the switching working mode is used as the target working mode.

[0016] Optionally, matching a corresponding control strategy according to the target operating mode, and using the control strategy to perform voltage control on the target system includes:

[0017] When the target operating mode is the energy storage unit control operating mode, matching a first control strategy corresponding to the energy storage unit control operating mode, and adopting the first control strategy to perform voltage control on the target system;

[0018] When the target working mode is the wave power generator set control working mode, a second control strategy corresponding to the wave power generator set control working mode is matched, and the second control strategy is used to perform voltage control on the target system;

[0019] When the target operating mode is the grid-connected unit control operating mode, a third control strategy corresponding to the grid-connected unit control operating mode is matched, and the third control strategy is used to perform voltage control on the target system.

[0020] Optionally, the first control strategy is specifically:

[0021] When the target bus voltage is in a preset overvoltage interval, performing a sectioned energy unloading operation on the target system;

[0022] Determining whether the target bus voltage after the section energy unloading is within the preset standard voltage range;

[0023] If the target bus voltage after the section unloading is not within the preset standard voltage range, a new energy power reduction operation is performed on the target system;

[0024] Determining whether the target bus voltage after the new energy power is reduced is within the preset standard voltage range;

[0025] If the target bus voltage after the power reduction of the new energy source is not within the preset standard voltage range, the power reduction operation of the generator set is performed on the target system until the target bus voltage after the power reduction of the generator set is within the preset standard voltage range;

[0026] When the target bus voltage is in a preset undervoltage interval, a generator set power boost operation is performed on the target system;

[0027] Determining whether the target bus voltage after the power of the generator set is increased is within the preset standard voltage range;

[0028] If the target bus voltage after the power of the generator set is increased is not within the preset standard voltage range, performing a new energy power increase operation on the target system;

[0029] Determining whether the target bus voltage after the new energy power is increased is within the preset standard voltage range;

[0030] If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to a grid-connected output power reduction operation until the target bus voltage after the grid-connected output power is reduced is within the preset standard voltage range.

[0031] Optionally, the second control strategy is specifically:

[0032] When the target bus voltage is in a preset overvoltage interval, energy storage charging operation is performed on the target system;

[0033] Determining whether the target bus voltage after the energy storage is charged is within the preset standard voltage range;

[0034] If the target bus voltage after the energy storage is charged is not within the preset standard voltage range, performing a sectioned energy unloading operation on the target system;

[0035] Determining whether the target bus voltage after the section energy unloading is within the preset standard voltage range;

[0036] If the target bus voltage after the section unloading is not within the preset standard voltage range, a new energy power reduction operation is performed on the target system until the target bus voltage after the new energy power reduction is within the preset standard voltage range;

[0037] When the target bus voltage is in a preset undervoltage interval, a new energy power boost operation is performed on the target system;

[0038] Determining whether the target bus voltage after the new energy power is increased is within the preset standard voltage range;

[0039] If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, performing energy storage and discharge operation on the target system;

[0040] Determining whether the target bus voltage after the energy storage is discharged is within the preset standard voltage range;

[0041] If the target bus voltage after the energy storage is discharged is not within the preset standard voltage range, the target system is subjected to a grid-connected output power reduction operation until the target bus voltage after the grid-connected output power is reduced is within the preset standard voltage range.

[0042] Optionally, the third control strategy is specifically:

[0043] When the target bus voltage is in a preset overvoltage interval, energy storage charging operation is performed on the target system;

[0044] Determining whether the target bus voltage after the energy storage is charged is within the preset standard voltage range;

[0045] If the target bus voltage after the energy storage is charged is not within the preset standard voltage range, performing a sectioned energy unloading operation on the target system;

[0046] Determining whether the target bus voltage after the section energy unloading is within the preset standard voltage range;

[0047] If the target bus voltage after the sectioned energy unloading is not within the preset standard voltage range, the target system is sequentially subjected to a new energy power reduction operation and a generator set power reduction operation until the target bus voltage after the generator set power reduction is within the preset standard voltage range;

[0048] When the target bus voltage is in a preset undervoltage interval, a generator set power boost operation is performed on the target system;

[0049] Determining whether the target bus voltage after the power of the generator set is increased is within the preset standard voltage range;

[0050] If the target bus voltage after the power of the generator set is increased is not within the preset standard voltage range, performing a new energy power increase operation on the target system;

[0051] Determining whether the target bus voltage after the new energy power is increased is within the preset standard voltage range;

[0052] If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to energy storage discharge operation until the target bus voltage after the energy storage discharge is within the preset standard voltage range.

[0053] A second aspect of the present invention provides a DC bus voltage control system for a wave power generation and transformation system, comprising:

[0054] A response module, used to respond to a control request for a target system, determine a target operating mode of the target system, and obtain a target bus voltage of the target system;

[0055] A comparison module, used to determine whether the target bus voltage is within a preset standard voltage range;

[0056] A control module is used to match a corresponding control strategy according to the target operating mode if the target bus voltage is not in the preset standard voltage range, and adopt the control strategy to perform voltage control on the target system until the target bus voltage is in the preset standard voltage range.

[0057] A third aspect of the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the DC bus voltage control method of the wave power generation and transformation system as described in any one of the above items.

[0058] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed, the DC bus voltage control method of the wave power generation and transformation system as described in any one of the above items is implemented.

[0059] A fifth aspect of the present invention provides a computer program product, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, wherein when the program instructions are executed by a computer, the computer executes the DC bus voltage control method for a wave power generation and transformation system as described in any one of the above items.

[0060] It can be seen from the above technical solutions that the present invention has the following advantages:

[0061] In the present invention, a control request for a target system is responded to, a target working mode of the target system is determined, and a target bus voltage of the target system is obtained, and it is determined whether the target bus voltage is in a preset standard voltage interval. If the target bus voltage is not in the preset standard voltage interval, a corresponding control strategy is matched according to the target working mode, and the control strategy is used to control the voltage of the target system until the target bus voltage is in the preset standard voltage interval; the present invention detects whether the bus voltage of a wave power generation and transformation system in a working mode exceeds the limit. When the limit is exceeded, the corresponding control strategy is matched according to the current working mode, and the control strategy is executed to accurately control the DC bus voltage, so that flexible switching of work and stable grid-connected output can be achieved, and the entire wave power generation and transformation system can be stabilized, thereby achieving the goal of continuous and stable power generation of the wave power generation and transformation system; and solves the technical problem of how to achieve accurate control of the DC bus voltage under different working models, thereby improving the stability of the wave power generation and transformation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0063] Figure 1 A flowchart of a method for controlling a DC bus voltage of a wave power generation and transformation system provided in Embodiment 1 of the present invention;

[0064] Figure 2 A flow chart of the steps of a DC bus voltage control method for a wave power generation and transformation system provided in Embodiment 2 of the present invention;

[0065] Figure 3 This is the DC bus structure diagram of the wave power generation and transformation system;

[0066] Figure 4 It is the DC bus voltage control flow chart;

[0067] Figure 5 A structural block diagram of a DC bus voltage control system for a wave power generation and transformation system provided in Embodiment 3 of the present invention;

[0068] Figure 6 This is a structural block diagram of a computer device provided in Embodiment 4 of the present invention. DETAILED DESCRIPTION

[0069] The embodiments of the present invention provide a method and system for controlling a DC bus voltage of a wave power generation and transformation system, which are used to solve the technical problem of how to achieve accurate control of the DC bus voltage under different working modes, thereby improving the stability of the wave power generation and transformation system.

[0070] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0071] Aiming at the characteristics of power conversion and power delivery of large-scale wave power generation devices, the present invention proposes a DC bus voltage control method for a wave power generation and transformation system in order to stabilize the DC bus voltage, provide a stable and continuous power supply to the power grid, support multi-group mode switching, improve system safety, and realize unattended operation. By analyzing the current operating status of the system, the working mode and working parameters of subsystems such as the wave power generator set and the energy storage unit, photovoltaic unit, wind power unit, and other new energy units are automatically controlled in real time, thereby meeting the power demand of the station equipment of the wave power generation device, maintaining the stability of the DC bus voltage, and making the system continuously and stably operate automatically.

[0072] It should be noted that the present invention provides a variety of combined DC bus voltage control methods, which can achieve full automatic control, flexible switching, no need for manual intervention, time-saving and labor-saving, safe and reliable. The present invention can meet the current needs of wave energy power generation devices with multiple energy complementary combinations, can achieve precise control of bus voltage, is conducive to flexible switching under system operation, inspection, maintenance and other working conditions, can maintain DC bus voltage stability for a long time, and can achieve unmanned operation, providing a stable and continuous power supply for the power grid.

[0073] See also Figure 1 , Figure 1 A flowchart of the steps of a DC bus voltage control method for a wave power generation and transformation system provided in Embodiment 1 of the present invention.

[0074] The present invention provides a DC bus voltage control method for a wave power generation and transformation system, comprising:

[0075] Step 101 : responding to a control request for a target system, determining a target operating mode of the target system, and acquiring a target bus voltage of the target system.

[0076] The target system refers to the wave power generation and transformation system. The wave power generation and transformation system is a power generation system that uses a DC bus for energy exchange. The various units in the wave power generation and transformation system are connected through a DC bus, and energy is exchanged on this basis to achieve a dynamic balance of the power generation and transformation system.

[0077] Control request, control request includes voltage control request and mode switching request, wherein the voltage control request refers to a request instruction for DC bus voltage control for the target system, and the mode switching request refers to a request instruction for switching the working mode received by the target system from external transmission.

[0078] DC bus voltage control refers to controlling the bus voltage of the target system to fluctuate within a certain range to prevent the units connected to the DC bus from failing to operate normally or being disconnected due to the DC bus voltage being too high or too low. At the same time, the equipment of each unit works under rated electrical conditions to increase the service life of the equipment.

[0079] The target working mode refers to the working mode in which the target system will run.

[0080] The target bus voltage refers to the bus voltage of the target system when it is in the target working mode at the current moment.

[0081] In an embodiment of the present invention, a request instruction for controlling the DC bus voltage of a target system is responded to, the current operating mode of the target system is determined, and a request instruction for switching the operating mode transmitted externally is received and read to determine the switching operating mode to be switched by the target system. A comprehensive analysis and judgment is performed based on the operating mode and the switching mode to determine the target operating mode to be operated by the target system, and the bus voltage of the target system in the target operating mode at the current moment is obtained.

[0082] Step 102: Determine whether the target bus voltage is within a preset standard voltage range.

[0083] The preset standard voltage range refers to a preset system steady-state voltage range, within which the target system can operate safely, stably and efficiently.

[0084] In an embodiment of the present invention, it is determined whether the target bus voltage of the target system is within a preset standard voltage range.

[0085] Step 103: If the target bus voltage is not within the preset standard voltage range, a corresponding control strategy is matched according to the target working mode, and the control strategy is used to control the voltage of the target system until the target bus voltage is within the preset standard voltage range.

[0086] In an embodiment of the present invention, if the target bus voltage is not in the preset standard voltage range, the corresponding control strategy is matched according to the target operating mode, and the control strategy is used to control the voltage of the target system until the target bus voltage is in the preset standard voltage range.

[0087] In the present invention, a control request for a target system is responded to, a target working mode of the target system is determined, and a target bus voltage of the target system is obtained, and it is determined whether the target bus voltage is in a preset standard voltage interval. If the target bus voltage is not in the preset standard voltage interval, a corresponding control strategy is matched according to the target working mode, and the control strategy is used to control the voltage of the target system until the target bus voltage is in the preset standard voltage interval; the present invention detects whether the bus voltage of a wave power generation and transformation system in a working mode exceeds the limit. When the limit is exceeded, the corresponding control strategy is matched according to the current working mode, and the control strategy is executed to accurately control the DC bus voltage, so that flexible switching of work and stable grid-connected output can be achieved, and the entire wave power generation and transformation system can be stabilized, thereby achieving the goal of continuous and stable power generation of the wave power generation and transformation system; and solves the technical problem of how to achieve accurate control of the DC bus voltage under different working models, thereby improving the stability of the wave power generation and transformation system.

[0088] See also Figure 2 , Figure 2 A flowchart of the steps of a DC bus voltage control method for a wave power generation and transformation system provided in Embodiment 2 of the present invention.

[0089] A DC bus voltage control method for a wave power generation and transformation system provided by the present invention is applied to a wave power generation and transformation system;

[0090] See also Figure 3 , Figure 3 The DC bus structure diagram of the wave power generation and transformation system. The wave power generation and transformation system includes a wave power generator set, a grid-connected unit, a power consumption unit, an energy unloading unit, an energy storage unit and a new energy power generation unit. The wave power generator set, the grid-connected unit, the power consumption unit, the energy unloading unit, the energy storage unit and the new energy power generation unit are all connected to the DC bus.

[0091] It should be noted that each component unit in the wave power generation and transformation system is controlled by a controller, and the DC bus voltage control method of the wave power generation and transformation system is mainly implemented by a hierarchical control system composed of controllers of each unit.

[0092] The main controller is the top-level control of the control system, and exchanges information and controls with the power unit controller, grid-connected unit controller, wave generator controller, photovoltaic unit controller, energy storage unit controller, and new energy unit controller through the switch.

[0093] The main controller mainly performs advanced functions of energy management, obtains all operating status and operating data of the current system, coordinates the control sequence and methods between units, and realizes advanced functions such as data integration, comprehensive judgment, and parameter command issuance between units.

[0094] The unit controller mainly coordinates and controls the equipment of the unit, collects the operating status data of the unit and uploads it to the central controller. At the same time, the unit controller executes the control and parameter instructions of the main controller, controls the equipment of the unit or changes the operating parameters.

[0095] The wave power generator set is composed of multiple wave power generator sets. Under certain wave conditions, the wave power generator set can realize generator speed control through accumulators, hydraulic proportional valves, inverter equipment, etc., thereby realizing stable control of bus voltage. In the power generation state, the generator's electric energy is collected by the inverter to the DC bus and enters the system.

[0096] The grid-connected unit is mainly composed of a frequency converter. The grid-connected unit controller can achieve stable control of the DC bus voltage through the stable voltage of the large power grid by controlling the working mode of the frequency converter.

[0097] The power-consuming unit, mainly composed of the frequency converter, continuously consumes electric energy as the load of the system; the inverter works in the voltage-frequency mode, controls the output voltage and frequency, and provides a stable 380V / 50Hz power supply, but cannot provide support for the stability of the DC bus voltage.

[0098] The energy unloading unit is mainly composed of one or more groups of resistors or other energy storage and power consumption units, which can consume the excess power on the system or store it in other forms. When the bus voltage is too high, this unit can be put into use to quickly reduce the bus voltage.

[0099] Energy storage unit, the energy storage unit controller controls its charging current and discharging current, controls the battery to perform periodic charging and discharging cycles according to the charging and discharging parameters, and can also support the bus voltage.

[0100] The new energy unit can be composed of one or more new energy units, such as photovoltaic units and wind units. Its power generation unit controller controls the start and stop of the new energy power generation unit and the limit of its maximum output power by sending control parameters to the corresponding unit controller.

[0101] In order to avoid large fluctuations in the DC bus voltage and control confusion during the normal operation of the wave power generation and transformation system, there is only one type of sub-unit that performs the main control of the bus voltage, and other sub-units mainly perform auxiliary control to cooperate in completing the precise control of the voltage and maintain system stability.

[0102] In the normal operation mode of the wave power generation and transformation system, the energy storage unit and the power consumption unit work fixedly; the wave power generator set, the grid-connected unit, the energy unloading unit, the photovoltaic, wind power and other new energy units work on demand. The working modes of each unit are as follows:

[0103] (1) The grid-connected unit can be used as the main control source for balancing the DC bus voltage. When necessary, the inverter of the grid-connected unit can be switched to the AFE mode, using the grid voltage to stabilize the DC bus voltage in a reasonable range, providing a stable DC bus voltage to the wave power generation device. If the grid-connected unit is not required to balance the DC bus voltage, the grid-connected unit can operate in the PQ mode. The grid-connected unit continuously transmits the electricity produced by the device to the large grid according to the grid dispatch requirements.

[0104] (2) The energy storage unit can be used as the main control source for balancing the DC bus voltage. The energy storage unit works in voltage control mode to stabilize the DC bus voltage and stabilize the DC bus voltage in a reasonable range. In voltage control mode, if the power supply power in the system is lower than the load power, the energy storage unit will discharge, thereby increasing the bus voltage; if the power supply power in the wave power generation device is higher than the load power, the energy storage unit will charge, thereby reducing the bus voltage. When the energy storage battery is full or discharged, it can no longer provide voltage support. If the energy storage unit is not needed to balance the DC bus voltage, the energy storage unit can be controlled to cycle periodically at a slow rate to increase the battery life.

[0105] (3) The wave generator set can be used as the main control source for balancing the DC bus voltage under a certain range of wave conditions. Under a certain range of wave conditions, the wave generator set can support the DC bus voltage by adjusting the proportional valve to control the speed. When the DC bus voltage is low, the wave generator set increases the speed to increase the power generation, thereby increasing the bus voltage; when the DC bus voltage is high, the wave generator set appropriately reduces the speed to reduce the power generation, thereby reducing the bus voltage.

[0106] (4) The new energy unit can also assist in controlling the DC bus voltage balance. When the DC bus voltage is too high, the output of the new energy unit can be limited to assist in reducing the bus voltage. In other cases, the new energy unit generates electricity according to actual demand.

[0107] (5) The energy unloading unit mainly plays a role in reducing the balance of the DC bus voltage. When the DC bus voltage rises above the target value, the energy unloading unit can be put into operation step by step to discharge the excess energy until the bus voltage falls back to the normal range.

[0108] The DC bus voltage control method mainly selects one of the units to control the DC bus voltage according to the current working mode of the system, and controls the working mode or working parameters of the unit to maintain the bus voltage stability. At the same time, other units of the control system assist and cooperate to jointly maintain the long-term stability of the bus voltage. Combined with the characteristics of wave power generation devices, it is generally carried out in accordance with the principle that wave power generation and new energy power generation can be fully developed when power is insufficient, and energy storage is charged first when power is surplus to improve system stability.

[0109] Step 201 : responding to a voltage control request for a target system, determining that the target system is in an operating mode in an operating state.

[0110] In the embodiment of the present invention, in response to the voltage control request for the target system, the central controller first checks the current operating state of the wave power generation and transformation system, and then confirms the current operating mode of the system.

[0111] It should be noted that here the central controller is used to check the working status of the current target system, and confirm the current operating mode of the system based on the working status, which specifically refers to the historical settings or script settings or the backup status before the last central controller was shut down. The target system runs according to the historical settings or script settings or the backup status before the last central controller was shut down, which can be understood as the working status maintained before new human intervention.

[0112] Step 202: Receive and read a mode switching request, and determine a switching working mode of the target system.

[0113] In the embodiment of the present invention, at the same time, whether there is an external request instruction for switching the working mode is detected through the communication network. When the request instruction is detected, the request instruction is read to determine the working mode to be switched by the target system, that is, the working mode is switched.

[0114] It is worth mentioning that when no request instruction is detected, that is, when a mode switching request is received, the running working mode is directly used as the target working mode.

[0115] It should be noted that the mode switching request is an instruction from the system to actively execute the dispatch or on-site operator (i.e., external request instruction). The number of external instructions is much larger than the number of working modes. That is, it is possible that the A, B, and C external request instructions are all operated in the working mode where the energy storage unit controls the bus voltage, and the current operating mode of the target system is also the working mode where the energy storage unit controls the bus voltage. The two are the same, and the system does not need to switch the working mode. The corresponding instruction operations are executed in the same mode, but the execution of some instructions will involve the switching of working modes.

[0116] Step 203: Compare the running working mode with the switching working mode.

[0117] In the embodiment of the present invention, the running working mode and the switching working mode are compared.

[0118] Step 204: If the comparison is consistent, the running working mode is used as the target working mode.

[0119] In an embodiment of the present invention, if the running working mode is consistent with the switching working mode, for example, taking the instruction number of the request instruction carried by the mode switching request as one, the running working mode of the current target system is the energy storage unit control working mode, and the request instruction carried by the externally transmitted mode switching request is to switch the working mode of the target system to the energy storage unit control working mode, then the two modes are consistent, and the energy storage unit control working mode is directly used as the target working mode.

[0120] It should be noted that when there are multiple request instructions, the one with the larger number shall prevail. For example, when three external request instructions are received, external request instructions A and B are for operation in the working mode of the energy storage unit controlling the bus voltage, and external request instruction C is for operation in the working mode of the grid-connected unit controlling the bus voltage, the target working mode that needs to be switched is to operate in the working mode of the energy storage unit controlling the bus voltage.

[0121] Step 205: If the comparison is inconsistent, the switching working mode is used as the target working mode.

[0122] In an embodiment of the present invention, if the operating working mode is inconsistent with the switching working mode, for example, the operating working mode of the current target system is the energy storage unit control working mode, and the request instruction carried by the externally transmitted mode switching request is to switch the working mode of the target system to the grid-connected unit control working mode, then the two modes are inconsistent, and the grid-connected unit control working mode is directly used as the target working mode.

[0123] Step 206: Obtain the target bus voltage of the target system.

[0124] In an embodiment of the present invention, a target bus voltage of a target system is acquired.

[0125] Step 207: Determine whether the target bus voltage is within a preset standard voltage range.

[0126] In the embodiment of the present invention, it is determined whether the target bus voltage of the target system is within a preset standard voltage range, that is, it is determined whether the target bus voltage of the target system is out of limit.

[0127] Step 208: If the target bus voltage is not within the preset standard voltage range, a corresponding control strategy is matched according to the target working mode, and the control strategy is used to control the voltage of the target system until the target bus voltage is within the preset standard voltage range.

[0128] See also Figure 4 , Figure 4 It is the DC bus voltage control flow chart;

[0129] In the present invention, three working modes are set, one of the three working modes is selected, and one type of unit is selected to directly control the DC bus voltage, while the remaining units perform auxiliary control or no control.

[0130] Further, step 208 may include the following sub-steps:

[0131] S11, if the target bus voltage is not within the preset standard voltage range;

[0132] S12. Match the corresponding control strategy according to the target working mode, and use the control strategy to control the voltage of the target system until the target bus voltage is in a preset standard voltage range.

[0133] Further, S12 may include the following sub-steps:

[0134] S121. When the target operating mode is the energy storage unit control operating mode, a first control strategy corresponding to the energy storage unit control operating mode is matched, and the first control strategy is used to perform voltage control on the target system.

[0135] In an embodiment of the present invention, when the target operating mode of the target system is the energy storage unit control operating mode, the energy storage unit control operating mode is used to retrieve the preset control strategy database, match the corresponding first control strategy, and use the first control strategy to control the voltage of the target system. The first control strategy is controlled by the energy storage unit.

[0136] It is worth mentioning that the preset control strategy database is a key-value pair database, which refers to a key-value pair database established according to the association between the target working mode of the target system and the control strategy, wherein the target working mode is used as the key and the control strategy is used as the value.

[0137] Furthermore, the first control strategy is specifically:

[0138] A11. When the target bus voltage is in the preset overvoltage range, the target system is subjected to a section-by-section energy unloading operation;

[0139] The preset overvoltage range refers to the voltage range in which the current bus voltage and development trend are too high, exceeding the preset standard voltage range, and reaching a voltage range that may cause harm to the insulation performance of electrical equipment, normal operating status and stability of the power system.

[0140] The staged energy unloading operation refers to the step-by-step operation of unloading energy by putting the energy unloading unit into operation. The energy unloading unit is a device or equipment combination specially used to consume excess energy. The energy unloading unit is put into operation in stages according to a certain order and steps.

[0141] In an embodiment of the present invention, an energy storage unit is selected to directly control the DC bus voltage, and the central controller sends a voltage working mode instruction to the energy storage unit BMS, and at the same time sends corresponding parameters such as charge and discharge current limits, and the energy storage unit is responsible for completing the main control of the DC bus voltage. Then the central controller makes a comprehensive judgment to determine whether the current bus voltage and development trend are too low or too high. When the target bus voltage of the target system is in the preset overvoltage interval, that is, the central controller calculates and determines that the target system is in the energy storage unit control working mode, the target bus voltage development trend after adjustment by the energy storage unit will be too high, then the central controller sends instructions to the energy unloading unit controller, and gradually puts the energy unloading unit into operation in sections for energy unloading.

[0142] A12. Determine whether the target bus voltage after section energy unloading is within the preset standard voltage range.

[0143] In an embodiment of the present invention, it is determined whether the target bus voltage after section energy unloading is within a preset standard voltage range.

[0144] A13. If the target bus voltage after section unloading is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0145] In an embodiment of the present invention, if the target bus voltage after segmented energy unloading is within a preset standard voltage range, that is, the central controller calculates and determines that the bus voltage meets the standard after adjustment by the energy unloading unit, the target system is maintained in the target operating mode at the current moment and the control process is terminated.

[0146] A14. If the target bus voltage after section unloading is not within the preset standard voltage range, the target system is subjected to a new energy power reduction operation.

[0147] Renewable energy power reduction operation refers to the gradual reduction of the output of new energy units such as photovoltaic and wind power.

[0148] In an embodiment of the present invention, if the target bus voltage after section energy unloading is not within the preset standard voltage range, the target system is subjected to a new energy power reduction operation, that is, the central controller continues to issue instructions to the controllers of new energy units such as photovoltaic and wind power to gradually reduce the output of new energy units such as photovoltaic and wind power.

[0149] A15. Determine whether the target bus voltage after the new energy power is reduced is within the preset standard voltage range.

[0150] In an embodiment of the present invention, it is determined whether the target bus voltage after the new energy power is reduced is within a preset standard voltage range.

[0151] A16. If the target bus voltage after the new energy power is reduced is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0152] In an embodiment of the present invention, if the target bus voltage after the new energy power is reduced is within a preset standard voltage range, that is, the central controller calculates and determines that the bus voltage meets the standard after adjustment by the new energy unit, the target system is maintained in the target operating mode at the current moment and continues to operate, and the control process ends.

[0153] A17. If the target bus voltage after the new energy power is reduced is not within the preset standard voltage range, the generator power is reduced on the target system until the target bus voltage after the generator power is reduced is within the preset standard voltage range.

[0154] Generator set power reduction operation refers to reducing the output power of the generator set.

[0155] In the embodiment of the present invention, if the target bus voltage after the new energy power is reduced is not within the preset standard voltage range, the generator power reduction operation is performed on the target system, that is, the central controller sends an instruction to the wave generator controller, and the wave generator controller adjusts the output power, reduces the output power of the generator to adjust the voltage, until the stable control of the DC bus voltage is finally completed.

[0156] A18. When the target bus voltage is in the preset undervoltage range, the generator set power is increased for the target system.

[0157] The preset undervoltage range refers to the voltage range in which the current bus voltage and development trend are low and lower than the preset standard voltage range, which may affect the normal operation of electrical equipment, reduce equipment performance, or even cause equipment damage.

[0158] Generator set power boost operation refers to increasing the output power of the generator set.

[0159] In an embodiment of the present invention, when the target bus voltage is in a preset undervoltage interval, that is, the central controller calculates and determines that the target system is in the energy storage unit control working mode, the current bus voltage or development trend after adjustment by the energy storage unit will be low, then the central controller first sends an instruction to the wave power generator set controller to increase the output power of the generator set for voltage regulation.

[0160] A19. Determine whether the target bus voltage after the generator set power is increased is within the preset standard voltage range.

[0161] In an embodiment of the present invention, it is determined whether the target bus voltage after the power of the generator set is increased is within a preset standard voltage range.

[0162] A110. If the target bus voltage after the generator set power is increased is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0163] In the embodiment of the present invention, if the target bus voltage after the power of the generator set is increased is within the preset standard voltage range, that is, the central controller calculates and determines that the bus voltage after adjustment by the wave power generator set meets the standard, the target system is maintained in the target working mode at the current moment and continues to operate, and the control process ends.

[0164] A111. If the target bus voltage after the generator set power is increased is not within the preset standard voltage range, the target system is operated to increase the power of new energy.

[0165] The new energy power boost operation refers to gradually increasing the output of new energy units such as photovoltaics and wind power, such as adjusting between the maximum power and 0, especially when the new energy is not working at full power at the beginning. For example, the MPPT of photovoltaics is the control method of photovoltaic inverters. In fact, the output power of photovoltaic panels can be directly changed through the inverter, and adjusted between 0 and the maximum. Wind power can be controlled by blade pitch angle, generator rotor speed, etc., so as to gradually increase the output of new energy units such as photovoltaics and wind power.

[0166] In an embodiment of the present invention, if the target bus voltage after the power of the generator set is increased is not within the preset standard voltage range, a new energy power increase operation is performed on the target system, that is, the central controller continues to issue instructions to the controllers of new energy units such as photovoltaics and wind power, and gradually increases the output of new energy units such as photovoltaics and wind power.

[0167] A112. Determine whether the target bus voltage after the new energy power is increased is within the preset standard voltage range.

[0168] In an embodiment of the present invention, it is determined whether the target bus voltage after the new energy power is increased is within a preset standard voltage range.

[0169] A113. If the target bus voltage after the new energy power is increased is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0170] In an embodiment of the present invention, if the target bus voltage after the new energy power is increased is within the preset standard voltage range, that is, the central controller calculates and determines that the bus voltage meets the standard after adjustment by the new energy unit, the target system is maintained in the target working mode at the current moment and continues to operate, and the control process ends.

[0171] A114. If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system will be connected to the grid and the output power will be reduced until the target bus voltage after the grid-connected output power is reduced is within the preset standard voltage range.

[0172] The grid-connected output power reduction operation refers to the output power adjustment of the grid-connected unit, which increases the DC bus voltage by reducing the output power to the grid, and at the same time informs the dispatcher of the grid-connected output power reduction.

[0173] In an embodiment of the present invention, if the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to a grid-connected output power reduction operation, that is, the central controller sends a control instruction to the grid-connected unit to adjust the output power of the grid-connected inverter, thereby increasing the DC bus voltage in turn by reducing the output power to the grid. At the same time, the dispatcher is informed of the reduction in grid-connected output power through the communication network until the stable control of the DC bus voltage is finally completed.

[0174] S122: When the target working mode is the wave power generator set control working mode, a second control strategy corresponding to the wave power generator set control working mode is matched, and the second control strategy is used to perform voltage control on the target system.

[0175] In the embodiment of the present invention, when the target working mode of the target system is the wave power generator set control working mode, the wave power generator set control working mode is used to retrieve the preset control strategy database, match the corresponding second control strategy, and use the second control strategy to control the voltage of the target system. The second control strategy is controlled by the wave power generator set.

[0176] Furthermore, the second control strategy is specifically as follows:

[0177] A21. When the target bus voltage is in the preset overvoltage range, the target system is charged with energy storage.

[0178] Energy storage charging operation refers to adjusting the energy storage to charging mode to gradually absorb excess electrical energy.

[0179] In the embodiment of the present invention, if the wave power generator set is selected to directly control the DC bus voltage, the central controller sends a control instruction to the hydraulic system, and controls the speed and torque of the generator through the proportional valve, thereby controlling the output of the generator set, thereby completing the main control of the DC bus voltage. Then the central controller makes a comprehensive judgment to determine whether the current bus voltage and development trend are too low or too high. When the target bus voltage is in the preset overvoltage interval, that is, the central controller calculates and determines that the current bus voltage or development trend after adjustment by the wave power generator set is too high, the central controller sends parameters and control instructions to the energy storage unit BMS to adjust the energy storage to the charging mode and gradually absorb the excess electric energy.

[0180] A22. Determine whether the target bus voltage after energy storage charging is within the preset standard voltage range.

[0181] In an embodiment of the present invention, it is determined whether the target bus voltage after energy storage charging is within a preset standard voltage range.

[0182] A23. If the target bus voltage after energy storage charging is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0183] In an embodiment of the present invention, if the target bus voltage after energy storage charging is within a preset standard voltage range, that is, the central controller calculates and determines that the bus voltage after adjustment by the energy storage unit meets the standard, the target system is maintained in the target operating mode at the current moment and continues to operate, and the control process ends.

[0184] A24. If the target bus voltage after energy storage charging is not within the preset standard voltage range, the target system is subjected to section energy unloading operation.

[0185] In an embodiment of the present invention, if the target bus voltage after energy storage charging is not within the preset standard voltage range, that is, the central controller sends instructions to the energy unloading unit controller to gradually put the energy unloading unit into operation in sections for energy unloading.

[0186] A25. Determine whether the target bus voltage after section unloading is within the preset standard voltage range.

[0187] In an embodiment of the present invention, it is determined whether the target bus voltage after section energy unloading is within a preset standard voltage range.

[0188] A26. If the target bus voltage after section unloading is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0189] In an embodiment of the present invention, if the target bus voltage after segmented energy unloading is within a preset standard voltage range, that is, the central controller calculates and determines that the bus voltage meets the standard after adjustment by the energy unloading unit, the target system is maintained in the target operating mode at the current moment and the control process is terminated.

[0190] A27. If the target bus voltage after section unloading is not within the preset standard voltage range, the target system is subjected to a new energy power reduction operation until the target bus voltage after the new energy power reduction is within the preset standard voltage range.

[0191] Renewable energy power reduction operation refers to the gradual reduction of the output of new energy units such as photovoltaic and wind power.

[0192] In an embodiment of the present invention, if the target bus voltage after section energy unloading is not within the preset standard voltage range, the target system is subjected to a new energy power reduction operation, that is, the central controller continues to issue instructions to the controllers of new energy units such as photovoltaic and wind power, gradually reducing the output of new energy units such as photovoltaic and wind power, until the stable control of the DC bus voltage is finally completed.

[0193] A28. When the target bus voltage is in the preset undervoltage range, the target system is operated to increase the power of new energy.

[0194] In an embodiment of the present invention, when the target bus voltage is in a preset undervoltage interval, that is, the central controller calculates and determines that the current bus voltage or development trend after adjustment by the wave power generator set will be low, the central controller first sends instructions to the controllers of new energy units such as photovoltaic and wind power to gradually increase the output of new energy units such as photovoltaic and wind power.

[0195] A29. Determine whether the target bus voltage after the new energy power is increased is within the preset standard voltage range.

[0196] In an embodiment of the present invention, it is determined whether the target bus voltage after the new energy power is increased is within a preset standard voltage range.

[0197] A210. If the target bus voltage after the new energy power is increased is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0198] In an embodiment of the present invention, if the target bus voltage after the new energy power is increased is within the preset standard voltage range, that is, the central controller calculates and determines that the bus voltage meets the standard after adjustment by the new energy unit, the target system is maintained in the target working mode at the current moment and continues to operate, and the control process ends.

[0199] A211. If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to energy storage discharge operation.

[0200] Energy storage discharge operation refers to adjusting the energy storage to discharge mode.

[0201] In an embodiment of the present invention, if the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to energy storage discharge operation, that is, the central controller sends parameters and control instructions to the energy storage unit BMS to adjust the energy storage to the discharge mode and provide part of the electric energy.

[0202] A212. Determine whether the target bus voltage after energy storage discharge is within the preset standard voltage range.

[0203] In an embodiment of the present invention, it is determined whether the target bus voltage after the energy storage is discharged is within a preset standard voltage range.

[0204] A213. If the target bus voltage after energy storage discharge is within the preset standard voltage range, the target system is kept running in the target operating mode at the current moment.

[0205] In an embodiment of the present invention, if the target bus voltage after energy storage discharge is within a preset standard voltage range, that is, the central controller calculates and determines that the bus voltage meets the standard after adjustment by the energy storage unit, the target system is maintained in the target operating mode at the current moment and continues to operate, and the control process ends.

[0206] It is worth mentioning that the target system is kept running in the target working mode at the current moment, that is, no other units are required to assist in adjustment, maintain the current mode and parameters, and end the control process.

[0207] A214. If the target bus voltage after energy storage discharge is not within the preset standard voltage range, the target system is subjected to a grid-connected output power reduction operation until the target bus voltage after the grid-connected output power reduction is within the preset standard voltage range.

[0208] In an embodiment of the present invention, if the target bus voltage after energy storage discharge is not within a preset standard voltage range, the target system is subjected to a grid-connected output power reduction operation, that is, the central controller sends a control instruction to the grid-connected unit to adjust the output power of the grid-connected inverter, thereby increasing the DC bus voltage in turn by reducing the output power to the grid, and at the same time notifying the dispatcher of the grid-connected output power reduction through the communication network until the target bus voltage after the grid-connected output power reduction is within the preset standard voltage range.

[0209] S123. When the target operating mode is the grid-connected unit control operating mode, a third control strategy corresponding to the grid-connected unit control operating mode is matched, and the third control strategy is used to perform voltage control on the target system.

[0210] In an embodiment of the present invention, when the target operating mode of the target system is the grid-connected unit control operating mode, the grid-connected unit control operating mode is used to retrieve the preset control strategy database, match the corresponding third control strategy, and use the third control strategy to control the voltage of the target system. The third control strategy is controlled by the grid-connected unit.

[0211] Furthermore, the third control strategy is specifically as follows:

[0212] A31. When the target bus voltage is in the preset overvoltage range, the target system is charged with energy storage.

[0213] In the embodiment of the present invention, if the grid-connected unit is selected to directly control the DC bus voltage, the central controller sends a mode instruction to the grid-connected unit controller, and the grid-connected unit switches to the grid voltage tracking mode to complete the main control of the DC bus voltage. Then the central controller makes a comprehensive judgment to determine whether the current bus voltage and development trend are too low or too high. When the target bus voltage is in the preset overvoltage range, that is, the central controller calculates and determines that the current bus voltage or development trend after adjustment by the grid-connected unit is too high, the central controller first sends parameters and control instructions to the energy storage unit BMS to adjust the energy storage to the charging mode and gradually absorb the excess electric energy.

[0214] A32. Determine whether the target bus voltage after energy storage charging is within the preset standard voltage range.

[0215] In an embodiment of the present invention, it is determined whether the target bus voltage after energy storage charging is within a preset standard voltage range.

[0216] A33. If the target bus voltage after energy storage charging is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0217] In an embodiment of the present invention, if the target bus voltage after energy storage charging is within a preset standard voltage range, that is, the central controller calculates and determines that the bus voltage after adjustment by the energy storage unit meets the standard, the target system is maintained in the target operating mode at the current moment and continues to operate, and the control process ends.

[0218] A34. If the target bus voltage after energy storage charging is not within the preset standard voltage range, the target system is subjected to section energy unloading operation.

[0219] In an embodiment of the present invention, if the target bus voltage after energy storage charging is not within the preset standard voltage range, a segmented energy unloading operation is performed on the target system, that is, the central controller sends instructions to the energy unloading unit controller to gradually and segmentally put the energy unloading unit into operation for energy unloading.

[0220] A35. Determine whether the target bus voltage after section unloading is within the preset standard voltage range.

[0221] In an embodiment of the present invention, it is determined whether the target bus voltage after section energy unloading is within a preset standard voltage range.

[0222] A36. If the target bus voltage after section unloading is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0223] In an embodiment of the present invention, if the target bus voltage after section energy unloading is within a preset standard voltage range, that is, the central controller calculates and determines that the bus voltage after adjustment by the energy unloading unit meets the standard, the control process ends.

[0224] A37. If the target bus voltage after section unloading is not within the preset standard voltage range, the target system will be subjected to the new energy power reduction operation and the generator set power reduction operation in sequence until the target bus voltage after the generator set power reduction is within the preset standard voltage range.

[0225] In an embodiment of the present invention, if the target bus voltage after the sectioned energy unloading is not within the preset standard voltage range, the target system is first subjected to a new energy power reduction operation, that is, the central controller continues to issue instructions to the controllers of new energy units such as photovoltaics and wind power, and gradually increases the output of new energy units such as photovoltaics and wind power. If the target bus voltage after the new energy power reduction does not meet the standard, the target system continues to be subjected to a generator set power reduction operation, that is, the central controller continues to issue instructions to the wave power generator set controller, and the wave power generator set controller adjusts the output power to reduce the output power of the generator set until the target bus voltage after the generator set power reduction is within the preset standard voltage range.

[0226] A38. When the target bus voltage is in the preset undervoltage range, the generator set power is increased for the target system.

[0227] In an embodiment of the present invention, when the target bus voltage is in a preset undervoltage interval, that is, the central controller calculates and determines that the current bus voltage or development trend after adjustment by the grid-connected unit is low, the target system performs a generator set power boost operation, and the central controller sends an instruction to the wave power generator set controller to increase the output power of the generator set for voltage regulation.

[0228] A39. Determine whether the target bus voltage after the generator set power is increased is within the preset standard voltage range.

[0229] In an embodiment of the present invention, it is determined whether the target bus voltage after the power of the generator set is increased is within a preset standard voltage range.

[0230] A310. If the target bus voltage after the generator set power is increased is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0231] In the embodiment of the present invention, if the target bus voltage after the power of the generator set is increased is within the preset standard voltage range, that is, the central controller calculates and determines that the bus voltage after adjustment by the wave power generator set meets the standard, the target system is maintained in the target working mode at the current moment and continues to operate, and the control process ends.

[0232] A311. If the target bus voltage after the generator set power is increased is not within the preset standard voltage range, the target system will be operated to increase the power of new energy.

[0233] In an embodiment of the present invention, if the target bus voltage after the power of the generator set is increased is not within the preset standard voltage range, a new energy power increase operation is performed on the target system, that is, the central controller sends instructions to the controllers of new energy units such as photovoltaics and wind power to gradually increase the output of new energy units such as photovoltaics and wind power.

[0234] A312. Determine whether the target bus voltage after the new energy power is increased is within the preset standard voltage range.

[0235] In an embodiment of the present invention, it is determined whether the target bus voltage after the new energy power is increased is within a preset standard voltage range.

[0236] A313. If the target bus voltage after the new energy power is increased is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0237] In an embodiment of the present invention, if the target bus voltage after the new energy power is increased is within the preset standard voltage range, that is, the central controller calculates and determines that the bus voltage meets the standard after adjustment by the new energy unit, the target system is maintained in the target working mode at the current moment and continues to operate, and the control process ends.

[0238] A314. If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to energy storage discharge operation until the target bus voltage after energy storage discharge is within the preset standard voltage range.

[0239] In an embodiment of the present invention, if the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to energy storage discharge operation, that is, the central controller sends parameters and control instructions to the energy storage unit BMS to adjust the energy storage to the discharge mode and provide a portion of electric energy until the bus voltage reaches the standard. At the same time, the dispatching network is informed through the communication network that the grid voltage is low and the device has provided maximum support until the stable control of the DC bus voltage is finally completed.

[0240] Furthermore, the following steps may be included:

[0241] Step 209: If the target bus voltage is within the preset standard voltage range, the target system is kept running in the target working mode at the current moment.

[0242] In an embodiment of the present invention, if the target bus voltage is within a preset standard voltage range, the target system is kept running in the target operating mode at the current moment without the need for auxiliary adjustment by other units, the current target operating mode and parameters are maintained, and the control process is terminated.

[0243] In the present invention, the DC bus voltage is precisely controlled by combining a variety of control methods to achieve long-term stability of the DC bus voltage, thereby achieving long-term stability and unattended operation of the system. The wave power generation and transformation system is often composed of a variety of energy sources connected by a DC bus. The stability of the DC bus voltage determines the stability of the power generation and grid-connected output of the wave power generation and transformation system. Over-limit of the DC bus voltage will lead to system collapse or shutdown of some subsystems. In various working modes, the wave power generation and transformation system often requires different objects to stabilize the DC bus voltage. A variety of working modes can make system operation, inspection, maintenance and other work more flexible. By combining a variety of control methods to precisely control the DC bus voltage, it is possible to achieve flexible switching of work while stabilizing the grid-connected output and stabilizing the entire power generation and transformation system, thereby achieving the goal of continuous and stable power generation of the wave power generation device.

[0244] In the present invention, a control request for a target system is responded to, a target working mode of the target system is determined, and a target bus voltage of the target system is obtained, and it is determined whether the target bus voltage is in a preset standard voltage interval. If the target bus voltage is not in the preset standard voltage interval, a corresponding control strategy is matched according to the target working mode, and the control strategy is used to control the voltage of the target system until the target bus voltage is in the preset standard voltage interval; the present invention detects whether the bus voltage of a wave power generation and transformation system in a working mode exceeds the limit. When the limit is exceeded, the corresponding control strategy is matched according to the current working mode, and the control strategy is executed to accurately control the DC bus voltage, so that flexible switching of work and stable grid-connected output can be achieved, and the entire wave power generation and transformation system can be stabilized, thereby achieving the goal of continuous and stable power generation of the wave power generation and transformation system; and solves the technical problem of how to achieve accurate control of the DC bus voltage under different working models, thereby improving the stability of the wave power generation and transformation system.

[0245] See also Figure 5 , Figure 5 This is a structural block diagram of a DC bus voltage control system of a wave power generation and transformation system provided in Embodiment 3 of the present invention.

[0246] The present invention provides a DC bus voltage control system for a wave power generation and transformation system, comprising:

[0247] A response module 301 is used to respond to a control request for a target system, determine a target operating mode of the target system, and obtain a target bus voltage of the target system;

[0248] Comparison module 302, used to determine whether the target bus voltage is within a preset standard voltage range;

[0249] The control module 303 is used to match the corresponding control strategy according to the target working mode if the target bus voltage is not in the preset standard voltage range, and use the control strategy to control the voltage of the target system until the target bus voltage is in the preset standard voltage range.

[0250] Furthermore, the response module 301 includes:

[0251] The operation mode submodule is used to respond to the voltage control request of the target system and determine the operation mode in which the target system is in the operation state;

[0252] The switching working mode submodule is used to receive and read the mode switching request and determine the switching working mode of the target system;

[0253] The mode comparison submodule is used to compare the running working mode and switch the working mode;

[0254] A first processing submodule is used to set the running working mode as the target working mode if the comparison is consistent;

[0255] The second processing submodule is used to switch the working mode as the target working mode if the comparison is inconsistent.

[0256] Furthermore, the control module 303 includes:

[0257] A first control strategy submodule, for matching a first control strategy corresponding to the energy storage unit control working mode when the target working mode is the energy storage unit control working mode, and adopting the first control strategy to perform voltage control on the target system;

[0258] The second control strategy submodule is used to match the second control strategy corresponding to the wave power generator control working mode when the target working mode is the wave power generator control working mode, and adopt the second control strategy to perform voltage control on the target system;

[0259] The third control strategy submodule is used to match the third control strategy corresponding to the grid-connected unit control working mode when the target working mode is the grid-connected unit control working mode, and adopt the third control strategy to perform voltage control on the target system.

[0260] Furthermore, the first control strategy is specifically:

[0261] When the target bus voltage is in the preset overvoltage range, the target system is subjected to section-by-section energy unloading operation;

[0262] Determine whether the target bus voltage after section energy unloading is within the preset standard voltage range;

[0263] If the target bus voltage after section unloading is not within the preset standard voltage range, the target system is subjected to a new energy power reduction operation;

[0264] Determine whether the target bus voltage after the new energy power is reduced is within the preset standard voltage range;

[0265] If the target bus voltage after the power reduction of the new energy source is not within the preset standard voltage range, the power reduction operation of the generator set is performed on the target system until the target bus voltage after the power reduction of the generator set is within the preset standard voltage range;

[0266] When the target bus voltage is in the preset undervoltage range, the target system is subjected to a generator power boost operation;

[0267] Determine whether the target bus voltage after the generator set power is increased is within the preset standard voltage range;

[0268] If the target bus voltage after the power of the generator set is increased is not within the preset standard voltage range, the target system is operated to increase the power of new energy;

[0269] Determine whether the target bus voltage after the new energy power is increased is within the preset standard voltage range;

[0270] If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the grid-connected output power reduction operation is performed on the target system until the target bus voltage after the grid-connected output power is reduced is within the preset standard voltage range.

[0271] Furthermore, the second control strategy is specifically as follows:

[0272] When the target bus voltage is in the preset overvoltage range, the target system is charged with energy storage;

[0273] Determine whether the target bus voltage after energy storage charging is within a preset standard voltage range;

[0274] If the target bus voltage after energy storage charging is not within the preset standard voltage range, the target system is subjected to section energy unloading operation;

[0275] Determine whether the target bus voltage after section energy unloading is within the preset standard voltage range;

[0276] If the target bus voltage after the section unloading is not within the preset standard voltage range, the target system is operated to reduce the power of the new energy until the target bus voltage after the new energy power is reduced is within the preset standard voltage range;

[0277] When the target bus voltage is in the preset undervoltage range, the target system is operated to increase the power of new energy;

[0278] Determine whether the target bus voltage after the new energy power is increased is within the preset standard voltage range;

[0279] If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is discharged by energy storage;

[0280] Determine whether the target bus voltage after energy storage discharge is within a preset standard voltage range;

[0281] If the target bus voltage after energy storage discharge is not within the preset standard voltage range, the target system is subjected to a grid-connected output power reduction operation until the target bus voltage after the grid-connected output power reduction is within the preset standard voltage range.

[0282] Furthermore, the third control strategy is specifically as follows:

[0283] When the target bus voltage is in the preset overvoltage range, the target system is charged with energy storage;

[0284] Determine whether the target bus voltage after energy storage charging is within a preset standard voltage range;

[0285] If the target bus voltage after energy storage charging is not within the preset standard voltage range, the target system is subjected to section energy unloading operation;

[0286] Determine whether the target bus voltage after section energy unloading is within the preset standard voltage range;

[0287] If the target bus voltage after the section unloading is not within the preset standard voltage range, the target system is sequentially subjected to the new energy power reduction operation and the generator set power reduction operation until the target bus voltage after the generator set power reduction is within the preset standard voltage range;

[0288] When the target bus voltage is in the preset undervoltage range, the target system is subjected to a generator power boost operation;

[0289] Determine whether the target bus voltage after the generator set power is increased is within the preset standard voltage range;

[0290] If the target bus voltage after the power of the generator set is increased is not within the preset standard voltage range, the target system is operated to increase the power of new energy;

[0291] Determine whether the target bus voltage after the new energy power is increased is within the preset standard voltage range;

[0292] If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to energy storage discharge operation until the target bus voltage after the energy storage discharge is within the preset standard voltage range.

[0293] In the present invention, a control request for a target system is responded to, a target working mode of the target system is determined, and a target bus voltage of the target system is obtained, and it is determined whether the target bus voltage is in a preset standard voltage interval. If the target bus voltage is not in the preset standard voltage interval, a corresponding control strategy is matched according to the target working mode, and the control strategy is used to control the voltage of the target system until the target bus voltage is in the preset standard voltage interval; the present invention detects whether the bus voltage of a wave power generation and transformation system in a working mode exceeds the limit. When the limit is exceeded, the corresponding control strategy is matched according to the current working mode, and the control strategy is executed to accurately control the DC bus voltage, so that flexible switching of work and stable grid-connected output can be achieved, and the entire wave power generation and transformation system can be stabilized, thereby achieving the goal of continuous and stable power generation of the wave power generation and transformation system; and solves the technical problem of how to achieve accurate control of the DC bus voltage under different working models, thereby improving the stability of the wave power generation and transformation system.

[0294] See also Figure 6 , Figure 6 This is a structural block diagram of a computer device provided in Embodiment 4 of the present invention.

[0295] An electronic device according to an embodiment of the present invention includes: a memory 401 and a processor 402, wherein the memory 402 stores a computer program; when the computer program is executed by the processor 402, the processor 402 executes a DC bus voltage control method for a wave power generation and transformation system according to any of the above embodiments.

[0296] The memory 401 may be an electronic memory such as a flash memory, an EEPROM (electrically erasable programmable read-only memory), an EPROM, a hard disk or a ROM. The memory 401 has a storage space 403 for a program code 413 for executing any method step in the above method. For example, the storage space 403 for the program code may include individual program codes 413 for implementing the various steps in the above method, respectively. These program codes may be read from or written to one or more computer program products. These computer program products include program code carriers such as hard disks, compact disks (CDs), memory cards or floppy disks. The program code may be compressed, for example, in an appropriate form. When these codes are run by a computing and processing device, the computing and processing device performs the various steps in the method described above. These program codes may be read from or written to one or more computer program products. These computer program products include program code carriers such as hard disks, compact disks (CDs), memory cards or floppy disks. The program code may be compressed, for example, in an appropriate form. When these codes are executed by a computing and processing device, the computing and processing device is caused to execute the various steps of the above-described method for controlling the DC bus voltage of a wave power generation and transformation system.

[0297] Embodiment 5 of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the DC bus voltage control method of the wave power generation and transformation system as described in any of the above embodiments is implemented.

[0298] Embodiment 6 of the present invention further provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer executes the DC bus voltage control method of the wave power generation and transformation system as described in any of the above embodiments.

[0299] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0300] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0301] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0302] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0303] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0304] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A DC bus voltage control method for a wave power generation and transformation system, characterized in that: include: In response to a control request for a target system, determining a target operating mode of the target system, and acquiring a target bus voltage of the target system; Determining whether the target bus voltage is within a preset standard voltage range; If the target bus voltage is not within the preset standard voltage range, a corresponding control strategy is matched according to the target operating mode, and the control strategy is used to perform voltage control on the target system until the target bus voltage is within the preset standard voltage range.

2. The DC bus voltage control method of the wave power generation and transformation system according to claim 1 is characterized in that: The control request includes a voltage control request and a mode switching request, and the responding to the control request to the target system to determine the target operating mode of the target system includes: In response to the voltage control request for the target system, determining that the target system is in an operating mode in an operating state; Receiving and reading the mode switching request, and determining the switching working mode of the target system; comparing the running working mode with the switching working mode; If the comparison is consistent, the operating working mode is used as the target working mode; If the comparison is inconsistent, the switching working mode is used as the target working mode.

3. The DC bus voltage control method of a wave power generation and transformation system according to any one of claims 1 or 2, characterized in that: The matching of a corresponding control strategy according to the target working mode and adopting the control strategy to perform voltage control on the target system includes: When the target operating mode is the energy storage unit control operating mode, matching a first control strategy corresponding to the energy storage unit control operating mode, and adopting the first control strategy to perform voltage control on the target system; When the target working mode is the wave power generator set control working mode, a second control strategy corresponding to the wave power generator set control working mode is matched, and the second control strategy is used to perform voltage control on the target system; When the target operating mode is the grid-connected unit control operating mode, a third control strategy corresponding to the grid-connected unit control operating mode is matched, and the third control strategy is used to perform voltage control on the target system.

4. The DC bus voltage control method of the wave power generation and transformation system according to claim 3 is characterized in that: The first control strategy is specifically: When the target bus voltage is in a preset overvoltage interval, performing a sectioned energy unloading operation on the target system; Determining whether the target bus voltage after the section energy unloading is within the preset standard voltage range; If the target bus voltage after the section unloading is not within the preset standard voltage range, a new energy power reduction operation is performed on the target system; Determining whether the target bus voltage after the new energy power is reduced is within the preset standard voltage range; If the target bus voltage after the power reduction of the new energy source is not within the preset standard voltage range, the power reduction operation of the generator set is performed on the target system until the target bus voltage after the power reduction of the generator set is within the preset standard voltage range; When the target bus voltage is in a preset undervoltage interval, a generator set power boost operation is performed on the target system; Determining whether the target bus voltage after the power of the generator set is increased is within the preset standard voltage range; If the target bus voltage after the power of the generator set is increased is not within the preset standard voltage range, performing a new energy power increase operation on the target system; Determining whether the target bus voltage after the new energy power is increased is within the preset standard voltage range; If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to a grid-connected output power reduction operation until the target bus voltage after the grid-connected output power is reduced is within the preset standard voltage range.

5. The DC bus voltage control method of the wave power generation and transformation system according to claim 3 is characterized in that: The second control strategy is specifically: When the target bus voltage is in a preset overvoltage interval, energy storage charging operation is performed on the target system; Determining whether the target bus voltage after the energy storage is charged is within the preset standard voltage range; If the target bus voltage after the energy storage is charged is not within the preset standard voltage range, performing a sectioned energy unloading operation on the target system; Determining whether the target bus voltage after the section energy unloading is within the preset standard voltage range; If the target bus voltage after the section unloading is not within the preset standard voltage range, a new energy power reduction operation is performed on the target system until the target bus voltage after the new energy power reduction is within the preset standard voltage range; When the target bus voltage is in a preset undervoltage interval, a new energy power boost operation is performed on the target system; Determining whether the target bus voltage after the new energy power is increased is within the preset standard voltage range; If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, performing energy storage and discharge operation on the target system; Determining whether the target bus voltage after the energy storage is discharged is within the preset standard voltage range; If the target bus voltage after the energy storage is discharged is not within the preset standard voltage range, the target system is subjected to a grid-connected output power reduction operation until the target bus voltage after the grid-connected output power is reduced is within the preset standard voltage range.

6. The DC bus voltage control method of the wave power generation and transformation system according to claim 3 is characterized in that: The third control strategy is specifically: When the target bus voltage is in a preset overvoltage interval, energy storage charging operation is performed on the target system; Determining whether the target bus voltage after the energy storage is charged is within the preset standard voltage range; If the target bus voltage after the energy storage is charged is not within the preset standard voltage range, performing a sectioned energy unloading operation on the target system; Determining whether the target bus voltage after the section energy unloading is within the preset standard voltage range; If the target bus voltage after the sectioned energy unloading is not within the preset standard voltage range, the target system is sequentially subjected to a new energy power reduction operation and a generator set power reduction operation until the target bus voltage after the generator set power reduction is within the preset standard voltage range; When the target bus voltage is in a preset undervoltage interval, a generator set power boost operation is performed on the target system; Determining whether the target bus voltage after the power of the generator set is increased is within the preset standard voltage range; If the target bus voltage after the power of the generator set is increased is not within the preset standard voltage range, performing a new energy power increase operation on the target system; Determining whether the target bus voltage after the new energy power is increased is within the preset standard voltage range; If the target bus voltage after the new energy power is increased is not within the preset standard voltage range, the target system is subjected to energy storage discharge operation until the target bus voltage after the energy storage discharge is within the preset standard voltage range.

7. A DC bus voltage control system for a wave power generation and transformation system, characterized in that: include: A response module, used to respond to a control request for a target system, determine a target operating mode of the target system, and obtain a target bus voltage of the target system; A comparison module, used to determine whether the target bus voltage is within a preset standard voltage range; A control module is used to match a corresponding control strategy according to the target operating mode if the target bus voltage is not in the preset standard voltage range, and adopt the control strategy to perform voltage control on the target system until the target bus voltage is in the preset standard voltage range.

8. An electronic device, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the DC bus voltage control method of the wave power generation and transformation system as described in any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the DC bus voltage control method of the wave power generation and transformation system as described in any one of claims 1 to 6 is implemented.

10. A computer program product, characterized in that The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, wherein the computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer is enabled to execute the DC bus voltage control method for a wave power generation and transformation system according to any one of claims 1 to 6.

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