Energy Cooperative Control Method, Device and Equipment for New Energy Island Sending System

Abstract

The present application relates to a method, device and equipment for coordinated energy control of a new energy island transmission system. The method for coordinated energy control of the new energy island transmission system uses a V / f control mode as the outer loop control link of a double closed loop at the sending end to control the operation of a flexible direct current transmission system according to a DC side fault signal, thereby providing a stable AC voltage for the new energy island transmission system. The DC current output by the flexible direct current transmission system is controlled to be 0, and the full-bridge module in the flexible direct current transmission system is controlled to output a negative voltage, so as to achieve the goal of discharging the DC side energy of the flexible direct current transmission system and realize the clearing of DC faults; the AC energy consumption device is controlled according to the number of groups put into operation to achieve the purpose of absorbing surplus power, avoiding overvoltage and overcurrent phenomena in the new energy island transmission system, and realizing rapid balance of transient process energy, thereby solving the problems of difficult clearing of DC side faults and transient energy imbalance during faults in existing new energy island transmission systems.

Description

Technical Field

[0001] The present application relates to the technical field of new energy power systems, and in particular to an energy collaborative control method, device and equipment for a new energy island transmission system. Background Art

[0002] Guided by the goals of achieving carbon peak and carbon neutrality, the development of wind and solar energy resources will be further unlocked. In particular, large-scale new energy bases in deserts, Gobi deserts, and other desolate areas will be further developed. Furthermore, because new energy resources and load centers are significantly inversely distributed, the power grids where these bases are located are generally weak. Therefore, the use of flexible direct current (HVDC) to transmit 100% of the new energy to the load centers for consumption is a key technical solution for large-scale wind and solar power bases.

[0003] In islanding scenarios, the Flexible DC transmission system replaces traditional rotating equipment to provide stable AC voltage for the renewable energy transmission system. It is also the sole channel for renewable energy transmission in isolated islands. Therefore, faults on the DC side of the Flexible DC transmission system pose a significant challenge to the stability of the renewable energy transmission system. On the one hand, if the Flexible DC transmission system is unable to provide stable AC voltage due to a DC fault, the renewable energy station at the sending end of the renewable energy transmission system will not be able to maintain stable operation. On the other hand, during the fault, renewable energy power will continue to be fed into the Flexible DC transmission system, generating a large amount of surplus power, which may cause overvoltage and overcurrent in the Flexible DC transmission system, further paralyzing the Flexible DC transmission system and disconnecting renewable energy from the grid. If the cross-regional DC transmission line is long and has a large amount of energy storage, clearing the overhead line fault in the renewable energy transmission system will be more difficult. Summary of the Invention

[0004] The embodiments of the present application provide a method, device and equipment for energy collaborative control of a new energy island transmission system, which is used to solve the technical problems of the existing new energy island transmission system in which DC side faults are difficult to clear and transient energy imbalance occurs during faults.

[0005] In order to achieve the above objectives, the embodiments of the present application provide the following technical solutions:

[0006] A method for collaborative energy control of a new energy island transmission system, the new energy island transmission system comprising a new energy station and a flexible direct current transmission system connected to the new energy station via an alternating current line, wherein an alternating current energy consuming device is provided on the alternating current line between the new energy station and the flexible direct current transmission system. The method for collaborative energy control comprises the following steps:

[0007] Obtain DC side fault signals and power surplus signals of the flexible DC transmission system, and obtain the rated capacity of a single group of AC energy consumption devices;

[0008] According to the DC side fault signal, a V / f control mode is adopted as an outer loop control link of the sending-end double closed loop of the flexible DC transmission system to control the full-bridge module of the flexible DC transmission system to output a negative voltage and a DC current of zero; and power transmission of the fault pole in the flexible DC transmission system is interrupted and the power of the fault pole is transferred to a non-fault pole of the flexible DC transmission system;

[0009] According to the power surplus signal, the fault pole output power and the fault pole rated output power of the flexible direct current transmission system are obtained; and according to the fault pole output power, the fault pole rated output power and the rated capacity of a single group, the number of groups of AC energy consuming devices put into operation is determined;

[0010] The operation of the AC energy consumption device of the new energy island transmission system is controlled according to the number of groups put into operation to absorb the surplus power of the flexible direct current transmission system.

[0011] Preferably, determining the number of groups of AC energy consuming devices put into operation based on the fault pole output power, the fault pole rated output power and the single group rated capacity includes: calculating the number of groups of AC energy consuming devices put into operation based on the fault pole output power, the fault pole rated output power and the single group rated capacity in combination with a formula for calculating the number of groups put into operation; the formula for calculating the number of groups put into operation is: A=(BC) / D, where A is the number of groups put into operation, B is the fault pole output power, C is the fault pole rated output power, and D is the single group rated capacity.

[0012] Preferably, the energy coordinated control method of the new energy island transmission system includes: according to the power surplus signal, increasing the AC voltage amplitude of the outer loop control link of the sending-end double closed loop of the flexible direct current transmission system to a first voltage.

[0013] Preferably, the first voltage is 525KV or 550KV.

[0014] Preferably, the step of obtaining the DC side fault signal and the power surplus signal of the flexible DC transmission system includes:

[0015] Real-time acquisition of electrical quantity data of the flexible DC transmission system, including DC voltage, DC current, and bus AC voltage of the DC converter station at different times;

[0016] Determine a voltage drop rate and a current increase rate according to the DC voltage and the DC current at two adjacent moments;

[0017] If the values of the voltage drop rate and the current increase rate are both greater than the value of the rate threshold, a DC side fault occurs in the flexible DC transmission system and a DC side fault signal is output;

[0018] If the bus AC voltage is greater than the voltage threshold, the flexible DC transmission system outputs a power surplus signal.

[0019] Preferably, the value of the rate threshold is 5, and the voltage threshold is 600KV.

[0020] The present application also provides an energy collaborative control device for a new energy island transmission system, the new energy island transmission system comprising a new energy station and a flexible direct current transmission system connected to the new energy station via an alternating current line, an alternating current energy consumption device being provided on the alternating current line between the new energy station and the flexible direct current transmission system, the energy collaborative control device comprising: a data acquisition module, a control module, a calculation module, and an input execution module;

[0021] The data acquisition module is used to obtain the DC side fault signal and power surplus signal of the flexible DC transmission system, and obtain the rated capacity of a single group of AC energy consuming devices;

[0022] The control module is configured to, based on the DC side fault signal, adopt a V / f control mode as an outer loop control link of the sending-end double closed loop of the flexible DC transmission system to control the full-bridge module of the flexible DC transmission system to output a negative voltage and a DC current of zero; and interrupt the transmission of power from the fault pole in the flexible DC transmission system and transfer the power from the fault pole to a non-fault pole in the flexible DC transmission system;

[0023] The calculation module is configured to obtain the fault pole output power and the fault pole rated output power of the flexible HVDC transmission system according to the power surplus signal; and determine the number of groups of AC energy consuming devices put into operation according to the fault pole output power, the fault pole rated output power, and the rated capacity of a single group;

[0024] The startup execution module is used to control the operation of the AC energy consumption device of the new energy island transmission system according to the number of startup groups, so as to absorb the surplus power of the flexible direct current transmission system.

[0025] Preferably, the calculation module is further used to calculate the number of groups put into operation of the AC energy consuming device based on the fault pole output power, the fault pole rated output power and the single group rated capacity, combined with the input group number calculation formula; the input group number calculation formula is: A=(BC) / D, where A is the number of groups put into operation, B is the fault pole output power, C is the fault pole rated output power, and D is the single group rated capacity.

[0026] Preferably, the control module is further configured to increase the AC voltage amplitude of the outer loop control link of the sending-end double closed loop of the flexible DC transmission system to a first voltage according to the power surplus signal.

[0027] The present application also provides a terminal device, including a processor and a memory;

[0028] The memory is used to store program code and transmit the program code to the processor;

[0029] The processor is used to execute the energy collaborative control method of the new energy island transmission system described above according to the instructions in the program code.

[0030] As can be seen from the above technical solutions, the embodiments of the present application have the following advantages: the energy coordinated control method, device, and equipment of the new energy island transmission system include obtaining a DC side fault signal and a power surplus signal of the flexible DC transmission system, and obtaining the rated capacity of a single group of AC energy consumption devices; based on the DC side fault signal, using a V / f control mode as the outer loop control link of the sending-end double closed loop of the flexible DC transmission system to control the full-bridge module of the flexible DC transmission system to output a negative voltage and a DC current of zero; and interrupting the transmission of the fault pole power in the flexible DC transmission system and transferring the power of the fault pole to the non-fault pole of the flexible DC transmission system; based on the power surplus signal, obtaining the fault pole output power and the fault pole rated output power of the flexible DC transmission system; determining the number of AC energy consumption device groups put into operation based on the fault pole output power, the fault pole rated output power, and the rated capacity of the single group; and controlling the operation of the AC energy consumption devices of the new energy island transmission system based on the number of groups put into operation to absorb the surplus power of the flexible DC transmission system. This energy collaborative control method for a new energy island transmission system uses a V / f control mode as the outer loop of a double closed-loop control scheme at the sending end to control the operation of the flexible direct current transmission system based on DC-side fault signals, providing a stable AC voltage for the new energy island transmission system. The DC current output by the flexible direct current transmission system is controlled to zero, and the full-bridge module in the flexible direct current transmission system is controlled to output a negative voltage to discharge the DC-side energy of the flexible direct current transmission system and clear the DC fault. The AC energy-consuming devices are controlled based on the number of groups in operation to absorb surplus power, avoid overvoltage and overcurrent in the new energy island transmission system, and achieve rapid energy balance during transient processes. This method solves the technical problems of existing new energy island transmission systems, such as the difficulty in clearing DC-side faults and the transient energy imbalance during faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0032] Figure 1 This is a flowchart of the steps of the energy collaborative control method of the new energy island transmission system according to an embodiment of the present application;

[0033] Figure 2 This is a framework diagram of the new energy island transmission system in the energy collaborative control method of the new energy island transmission system described in an embodiment of the present application;

[0034] Figure 3 This is a framework diagram of the energy collaborative control device of the new energy island transmission system in an embodiment of the present application. DETAILED DESCRIPTION

[0035] In order to make the purpose, features, and advantages of the invention of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described below are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0036] The embodiments of the present application provide a method, device and equipment for energy collaborative control of a new energy island transmission system, which is used to solve the technical problems of the existing new energy island transmission system in which DC side faults are difficult to clear and transient energy imbalance occurs during faults.

[0037] Example 1:

[0038] Figure 1 This is a flowchart of the steps of the energy collaborative control method of the new energy island transmission system described in an embodiment of the present application. Figure 2 This is a framework diagram of the new energy island transmission system in the energy collaborative control method of the new energy island transmission system described in an embodiment of the present application.

[0039] like Figure 2 As shown, in this embodiment of the present application, the isolated new energy transmission system includes a new energy station and a flexible direct current (HVDC) transmission system connected to the new energy station via an AC line. An AC energy consumption device is installed on the AC line between the new energy station and the flexible HVDC transmission system. A flexible direct current (HVDC) control module for controlling the operation of the flexible HVDC transmission system is also connected between the AC energy consumption device and the flexible HVDC transmission system.

[0040] like Figure 1 As shown, the embodiment of the present application provides an energy collaborative control method for a new energy island transmission system, comprising the following steps:

[0041] S1. Obtain a DC side fault signal and a power surplus signal of the flexible DC transmission system, and obtain a single group rated capacity of an AC energy consumption device.

[0042] It should be noted that obtaining the DC side fault signal and power surplus signal of the flexible DC transmission system in step S1, as well as obtaining the rated capacity of a single group of AC energy consumption devices, provides a data basis for energy coordination of the new energy island transmission system in subsequent steps.

[0043] In the embodiment of the present application, the step of obtaining a DC side fault signal and a power surplus signal of the flexible DC transmission system includes:

[0044] Real-time acquisition of electrical quantity data of the flexible DC transmission system, including DC voltage, DC current, and bus AC voltage of the DC converter station at different times;

[0045] Determine the voltage drop rate and current increase rate according to the DC voltage and DC current at two adjacent moments;

[0046] If the values of the voltage drop rate and the current increase rate are both greater than the value of the rate threshold, a DC side fault occurs in the flexible DC transmission system and a DC side fault signal is output;

[0047] If the bus AC voltage is greater than the voltage threshold, the flexible DC transmission system outputs a power surplus signal.

[0048] It should be noted that the voltage drop rate is the ratio of the DC voltage difference between two adjacent moments to the time difference between the two corresponding moments. Similarly, the current increase rate is the ratio of the DC current difference between two adjacent moments to the time difference between the two corresponding moments. In this embodiment, the rate threshold value can be selected as 5, and the voltage threshold value can be selected as 600 kV. In other embodiments, the rate threshold value and voltage threshold value can be set as required.

[0049] S2. Based on the DC side fault signal, the V / f control mode is adopted as the outer loop control link of the sending-end double closed loop of the flexible DC transmission system to control the full-bridge module of the flexible DC transmission system to output negative voltage and DC current to zero; and the power transmission of the fault pole in the flexible DC transmission system is interrupted and the power of the fault pole is transferred to the non-fault pole of the flexible DC transmission system.

[0050] It should be noted that in step S2, based on the DC side fault signal, the V / f control mode is used as the outer loop control link of the sending-end double closed loop to control the operation of the flexible DC transmission system, providing a stable AC voltage for the new energy island transmission system. The DC current output by the flexible DC transmission system is controlled to be 0, and the full-bridge module in the flexible DC transmission system is controlled to output a negative voltage to achieve the goal of discharging the DC side energy of the flexible DC transmission system and realize the DC fault clearing. At the same time, the transmission of the power of the fault pole in the flexible DC transmission system is also interrupted and all the power of the fault pole is transferred to the non-fault pole of the flexible DC transmission system. In this embodiment, the full-bridge module of the flexible DC transmission system is common knowledge in the field and will not be described in detail here. The division of the fault pole and non-fault pole of the flexible DC transmission system is also a relatively mature technology in the field and will not be described in detail here.

[0051] S3. Obtain the fault pole output power and the fault pole rated output power of the flexible DC transmission system based on the power surplus signal; determine the number of AC energy consumption devices put into operation based on the fault pole output power, the fault pole rated output power, and the rated capacity of a single group.

[0052] It should be noted that in step S3 , the number of groups of AC energy consuming devices put into operation is calculated based on the power surplus signal, and a pulse signal for controlling the operation of the AC energy consuming devices is generated and output to the AC energy consuming devices.

[0053] In an embodiment of the present application, the energy collaborative control method of the new energy island transmission system further includes increasing the AC voltage amplitude of the outer loop control link of the sending-end double closed loop of the flexible direct current transmission system to a first voltage according to the power surplus signal.

[0054] It should be noted that the first voltage can be selected as 550 kV. Specifically, when the new energy island transmission system is in a steady-state operation scenario, the first voltage can be selected as 525 kV.

[0055] Furthermore, the number of groups put into operation of the AC energy consuming device is calculated based on the fault pole output power, the fault pole rated output power and the rated capacity of a single group, in combination with the calculation formula for the number of groups put into operation; the calculation formula for the number of groups put into operation is: A = (BC) / D, where A is the number of groups put into operation, B is the fault pole output power, C is the fault pole rated output power, and D is the rated capacity of a single group.

[0056] S4. Control the operation of the AC energy consumption devices of the renewable energy island transmission system according to the number of groups put into operation to absorb the surplus power of the flexible DC transmission system.

[0057] It should be noted that the AC energy consumption device receives the pulse signal, controls the input of the AC energy consumption device according to the number of groups put into operation, and cooperates to increase the AC voltage amplitude of the V / f control mode to the first voltage to achieve the purpose of absorbing surplus power, avoiding overvoltage and overcurrent in the new energy island transmission system, and realizing rapid balance of energy in the transient process.

[0058] The present application provides an energy collaborative control method for a new energy island transmission system, the method comprising obtaining a DC side fault signal and a power surplus signal of a flexible direct current transmission system, and obtaining a single group rated capacity of an AC energy consumption device; based on the DC side fault signal, adopting a V / f control mode as an outer loop control link of a sending-end double closed loop of the flexible direct current transmission system to control the full-bridge module output negative voltage and DC current of the flexible direct current transmission system to be zero; and interrupting the transmission of power at a fault pole in the flexible direct current transmission system and transferring the power of the fault pole to a non-fault pole of the flexible direct current transmission system; based on the power surplus signal, obtaining the fault pole output power and the fault pole rated output power of the flexible direct current transmission system; determining the number of AC energy consumption device groups put into operation based on the fault pole output power, the fault pole rated output power and the single group rated capacity; and controlling the operation of the AC energy consumption devices of the new energy island transmission system based on the number of groups put into operation to absorb the surplus power of the flexible direct current transmission system. This energy collaborative control method for a new energy island transmission system uses a V / f control mode as the outer loop of a double closed-loop control scheme at the sending end to control the operation of the flexible direct current transmission system based on DC-side fault signals, providing a stable AC voltage for the new energy island transmission system. The DC current output by the flexible direct current transmission system is controlled to zero, and the full-bridge module in the flexible direct current transmission system is controlled to output a negative voltage to discharge the DC-side energy of the flexible direct current transmission system and clear the DC fault. The AC energy-consuming devices are controlled based on the number of groups in operation to absorb surplus power, avoid overvoltage and overcurrent in the new energy island transmission system, and achieve rapid energy balance during transient processes. This method solves the technical problems of existing new energy island transmission systems, such as the difficulty in clearing DC-side faults and the transient energy imbalance during faults.

[0059] In one embodiment of the present application, the energy collaborative control method of the new energy island transmission system also includes: after de-ionization is completed, restoring the normal control strategy of the new energy island transmission system, re-establishing the DC voltage, and obtaining the electrical quantity data of the flexible DC transmission system in real time to determine whether the flexible DC transmission system has resumed normal operation. If not, determining whether a DC side fault has occurred based on the content of the step of obtaining the DC side fault signal and power surplus signal of the flexible DC transmission system.

[0060] In an embodiment of the present application, the energy coordinated control method for the new energy island transmission system is capable of, first, controlling the flexible DC transmission system to maintain a V / f control mode during a DC side fault, and controlling the full-bridge module to output a negative voltage and zero DC current, thereby providing a stable AC voltage for the new energy island transmission system, while simultaneously achieving the purpose of arc extinguishing and deionizing, and discharging DC side energy. Second, during a DC side fault, if there is surplus power at the sending-end converter station of the flexible DC transmission system, it will quickly input AC energy consumption, while increasing the AC voltage amplitude of the V / f control mode of the flexible DC transmission system to absorb the surplus power, avoid overvoltage and overcurrent in the new energy island transmission system, and achieve rapid energy balance in the transient process. Thus, through the coordinated control of the flexible DC transmission system and the AC energy consumption device, the transient energy balance problem during the DC side fault of the flexible DC transmission system is solved, the AC voltage and frequency of the new energy island transmission system are maintained stable, the DC side fault of the flexible DC transmission system is quickly cleared, and the safe and stable operation of the new energy island transmission system after being disturbed by the DC fault is ensured.

[0061] Example 2:

[0062] Figure 3 This is a framework flow chart of the energy collaborative control device of the new energy island transmission system described in an embodiment of the present application.

[0063] like Figure 3 As shown, an embodiment of the present application provides an energy collaborative control device for a new energy island transmission system. The new energy island transmission system includes a new energy station and a flexible direct current transmission system connected to the new energy station via an AC line. An AC energy consumption device is provided on the AC line between the new energy station and the flexible direct current transmission system. The energy collaborative control device includes: a data acquisition module 10, a control module 20, a calculation module 30, and an input execution module 40;

[0064] The data acquisition module 10 is used to obtain the DC side fault signal and power surplus signal of the flexible DC transmission system, and obtain the rated capacity of a single group of AC energy consumption devices;

[0065] The control module 20 is configured to, based on a DC side fault signal, employ a V / f control mode as an outer loop control link of a sending-end double closed loop in the flexible DC transmission system to control the full-bridge module of the flexible DC transmission system to output a negative voltage and a DC current of zero; and to interrupt power transmission at the fault pole in the flexible DC transmission system and transfer the power at the fault pole to a non-fault pole in the flexible DC transmission system.

[0066] The calculation module 30 is configured to obtain the fault pole output power and the fault pole rated output power of the flexible HVDC transmission system according to the power surplus signal; and determine the number of AC energy consumption devices put into operation according to the fault pole output power, the fault pole rated output power, and the rated capacity of each group.

[0067] The activation execution module 40 is used to control the operation of the AC energy consumption devices of the new energy island transmission system according to the number of groups activated for operation, so as to absorb the surplus power of the flexible DC transmission system.

[0068] In the embodiment of the present application, the calculation module 30 is further used to calculate the number of groups put into operation of the AC energy consuming device based on the fault pole output power, the fault pole rated output power and the single group rated capacity, combined with the input group number calculation formula; the input group number calculation formula is: A = (BC) / D, where A is the number of groups put into operation, B is the fault pole output power, C is the fault pole rated output power, and D is the single group rated capacity.

[0069] In the embodiment of the present application, the control module 20 is further configured to increase the AC voltage amplitude of the outer loop control link of the sending-end double closed loop of the flexible DC transmission system to a first voltage according to the power surplus signal.

[0070] It should be noted that the modules in the device of Example 2 correspond to the steps in the method of Example 1. The content of the energy collaborative control method of the new energy island transmission system has been elaborated in detail in Example 1, and the content of the modules in the device will no longer be elaborated in this Example 2.

[0071] Example 3:

[0072] An embodiment of the present application provides a terminal device, including a processor and a memory;

[0073] A memory, configured to store program codes and transmit the program codes to a processor;

[0074] The processor is used to execute the above-mentioned energy coordinated control method of the new energy island transmission system according to the instructions in the program code.

[0075] It should be noted that the processor is configured to execute the steps of the aforementioned embodiment of the energy coordinated control method for a new energy island transmission system according to the instructions in the program code. Alternatively, the processor implements the functions of the modules / units in the aforementioned system / device embodiments when executing the computer program.

[0076] For example, a computer program may be divided into one or more modules / units, one or more of which are stored in a memory and executed by a processor to complete the present application. One or more modules / units may be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer program in a terminal device.

[0077] Terminal devices can be computing devices such as desktop computers, laptops, PDAs, and cloud servers. Terminal devices may include, but are not limited to, processors and memory. Those skilled in the art will appreciate that this does not constitute a limitation on terminal devices and may include more or fewer components than shown, or a combination of certain components, or different components. For example, terminal devices may also include input / output devices, network access devices, buses, and the like.

[0078] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0079] The memory can be an internal storage unit of a terminal device, such as a hard drive or memory. It can also be an external storage device, such as a plug-in hard drive, a SmartMedia Card (SMC), a Secure Digital (SD) card, or a flash memory card. Furthermore, the memory can include both the internal storage unit and external storage devices of the terminal device. The memory is used to store computer programs and other programs and data required by the terminal device. The memory can also be used to temporarily store data that has been output or is about to be output.

[0080] Those skilled in the art will 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.

[0081] In the several embodiments provided in this 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 merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as 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.

[0082] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0083] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0084] 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 application is essentially 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, and the computer software product is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0085] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. 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 application.

Claims

1. A method for energy collaborative control of a new energy island transmission system, the new energy island transmission system comprising a new energy station and a flexible direct current transmission system connected to the new energy station via an alternating current line, wherein an AC energy consuming device is provided on the AC line between the new energy station and the flexible direct current transmission system, characterized in that: The energy coordinated control method comprises the following steps: Obtain DC side fault signals and power surplus signals of the flexible DC transmission system, and obtain the rated capacity of a single group of AC energy consumption devices; According to the DC side fault signal, a V / f control mode is adopted as an outer loop control link of the sending-end double closed loop of the flexible DC transmission system to control the full-bridge module of the flexible DC transmission system to output a negative voltage and a DC current of zero; and power transmission of the fault pole in the flexible DC transmission system is interrupted and the power of the fault pole is transferred to a non-fault pole of the flexible DC transmission system; According to the power surplus signal, the fault pole output power and the fault pole rated output power of the flexible direct current transmission system are obtained; and according to the fault pole output power, the fault pole rated output power and the rated capacity of a single group, the number of groups of AC energy consuming devices put into operation is determined; Controlling the operation of the AC energy consumption devices of the new energy island transmission system according to the number of groups put into operation to absorb the surplus power of the flexible direct current transmission system; Determining the number of groups of AC energy consuming devices put into operation based on the fault pole output power, the fault pole rated output power, and the single group rated capacity includes: calculating the number of groups of AC energy consuming devices put into operation based on the fault pole output power, the fault pole rated output power, and the single group rated capacity in combination with a formula for calculating the number of groups put into operation; the formula for calculating the number of groups put into operation is: A=(BC) / D, where A is the number of groups put into operation, B is the fault pole output power, C is the fault pole rated output power, and D is the single group rated capacity. The steps of obtaining a DC side fault signal and a power surplus signal of the flexible DC transmission system include: Real-time acquisition of electrical quantity data of the flexible DC transmission system, including DC voltage, DC current, and bus AC voltage of the DC converter station at different times; Determine a voltage drop rate and a current increase rate according to the DC voltage and the DC current at two adjacent moments; If the values of the voltage drop rate and the current increase rate are both greater than the value of the rate threshold, a DC side fault occurs in the flexible DC transmission system and a DC side fault signal is output; If the bus AC voltage is greater than the voltage threshold, the flexible DC transmission system outputs a power surplus signal.

2. The energy collaborative control method of the new energy island transmission system according to claim 1 is characterized in that: include: According to the power surplus signal, the AC voltage amplitude of the outer loop control link of the sending-end double closed loop of the flexible direct current transmission system is increased to a first voltage.

3. The energy collaborative control method of the new energy island transmission system according to claim 2 is characterized in that: The first voltage is 525KV or 550KV.

4. The energy collaborative control method of the new energy island transmission system according to claim 1 is characterized in that: The value of the rate threshold is 5, and the voltage threshold is 600KV.

5. An energy collaborative control device for a new energy island transmission system, the new energy island transmission system comprising a new energy station and a flexible direct current transmission system connected to the new energy station via an AC line, an AC energy consumption device being provided on the AC line between the new energy station and the flexible direct current transmission system, characterized in that: The energy collaborative control device includes: a data acquisition module, a control module, a calculation module and an input execution module; The data acquisition module is used to obtain the DC side fault signal and power surplus signal of the flexible DC transmission system, and obtain the rated capacity of a single group of AC energy consuming devices; The control module is configured to, based on the DC side fault signal, adopt a V / f control mode as an outer loop control link of the sending-end double closed loop of the flexible DC transmission system to control the full-bridge module of the flexible DC transmission system to output a negative voltage and a DC current of zero; and interrupt the transmission of power from the fault pole in the flexible DC transmission system and transfer the power from the fault pole to a non-fault pole in the flexible DC transmission system; The calculation module is configured to obtain the fault pole output power and the fault pole rated output power of the flexible HVDC transmission system according to the power surplus signal; and determine the number of groups of AC energy consuming devices put into operation according to the fault pole output power, the fault pole rated output power, and the rated capacity of a single group; The activation execution module is configured to control the operation of the AC energy consumption devices of the new energy island transmission system according to the number of activation groups, so as to absorb the surplus power of the flexible direct current transmission system; The calculation module is further configured to calculate the number of groups of AC energy consuming devices put into operation based on the fault pole output power, the fault pole rated output power, and the single group rated capacity, in combination with a formula for calculating the number of groups put into operation; the formula for calculating the number of groups put into operation is: A=(BC) / D, where A is the number of groups put into operation, B is the fault pole output power, C is the fault pole rated output power, and D is the single group rated capacity; The steps of obtaining a DC side fault signal and a power surplus signal of the flexible DC transmission system include: Real-time acquisition of electrical quantity data of the flexible DC transmission system, including DC voltage, DC current, and bus AC voltage of the DC converter station at different times; Determine a voltage drop rate and a current increase rate according to the DC voltage and the DC current at two adjacent moments; If the values of the voltage drop rate and the current increase rate are both greater than the value of the rate threshold, a DC side fault occurs in the flexible DC transmission system and a DC side fault signal is output; If the bus AC voltage is greater than the voltage threshold, the flexible DC transmission system outputs a power surplus signal.

6. The energy cooperative control device for the new energy island transmission system according to claim 5 is characterized in that: The control module is further configured to increase the AC voltage amplitude of the outer loop control link of the sending-end double closed loop of the flexible DC transmission system to a first voltage according to the power surplus signal.

7. A terminal device, characterized in that: including a processor and a memory; The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the energy collaborative control method of the new energy island transmission system as described in any one of claims 1 to 4 according to the instructions in the program code.

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