A primary frequency regulation load shedding operation topology

Abstract

The present invention belongs to the technical field of primary frequency regulation of photovoltaic power stations, and in particular, relates to a primary frequency regulation load reduction operation topology structure. Specifically, it is a primary frequency regulation locked operation topology structure formed by the setting of a dedicated channel for primary frequency regulation, a load reduction energy storage device, and a frequency detection module. The present invention conducts an in-depth analysis of the technical solution for realizing the primary frequency regulation function of a photovoltaic power station, and optimizes the topological structure and corresponding hardware equipment of the photovoltaic power station. The present invention is aimed at the power control method of the photovoltaic power station, enhances the load reduction level of the photovoltaic power station, enables the photovoltaic power station to participate in the primary frequency regulation of the system, reduces the change in the system frequency, and improves the stability of the power output; shortens the time loss caused by the data transmission volume, and effectively improves the system response adjustment time.

Description

Technical Field

[0001] The present invention belongs to the field of primary frequency regulation technology of photovoltaic power station, and in particular relates to a primary frequency regulation load shedding operation topology structure, specifically a primary frequency regulation locking operation topology structure formed by setting a primary frequency regulation dedicated channel, a load shedding energy storage device, and a frequency detection module. Background Art

[0002] The setting of load shedding level will affect the effect of PV power station participating in primary frequency regulation. When the light becomes weaker, the load shedding level of PV power station decreases, reducing the spare capacity participating in primary frequency regulation, and its ability to participate in primary frequency regulation will be weakened. When the light becomes stronger, the load shedding level of PV power station increases, increasing the spare capacity participating in primary frequency regulation, and its ability to participate in primary frequency regulation will also become stronger. When large-scale PV power stations are connected to isolated power grids, the system inertia will be reduced, the frequency regulation capacity will be insufficient, and the safe and stable operation of the power grid will be affected.

[0003] There are many defects in the existing photovoltaic power station topology and participation in primary frequency regulation. Some boxes have slow refresh rates for measurement and control feedback values, or are not equipped with frequency detection modules, and the load can hardly meet the needs of primary frequency regulation. There are also many topologies that are connected to the remote control through the data acquisition and measurement and control device and then transmitted back to the receiving frequency modulation device or AGC system. Due to the large amount of uploaded data and the long feedback time, the adjustment time is far from meeting the goal of participating in primary frequency regulation. Summary of the invention

[0004] In view of the shortcomings of the above-mentioned prior art, the present invention provides a primary frequency modulation load reduction operation topology structure. Its purpose is to realize the power control mode for photovoltaic power stations, enhance the load reduction level of photovoltaic power stations, enable photovoltaic power stations to participate in the primary frequency modulation of the system, reduce the change of system frequency, improve the stability of power output; shorten the time loss caused by data transmission, and effectively improve the system response adjustment time.

[0005] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0006] A primary frequency regulation and load shedding operation topology structure includes a host, a frequency monitoring module is connected between the host and a remote control device, the output end of the frequency monitoring module is connected to the input end of a trigger-type fault recording device through a current input mode, and the triggering action process is fed back to the fault recording device through TCP104; the end of the host is coupled to a cache unit of an energy storage device through a dedicated channel, and the output end of the energy storage device is connected to a load and a power grid.

[0007] The topological structure is also provided with a measurement, control and data acquisition device, which has a reserved port for connecting to the control system; the measurement, control and data acquisition device is provided with a dedicated channel trigger judgment program to judge whether the power grid frequency reaches the primary frequency regulation range as a basis for starting the dedicated channel.

[0008] The dedicated channel is a single frequency modulation dedicated channel, which optimizes the message polling mechanism and uploads real-time active power when triggered.

[0009] The frequency monitoring module includes a system primary frequency regulation function locking / superposition logic algorithm. When it is detected that the grid frequency exceeds the primary frequency regulation threshold, the frequency regulation amount and the active power regulation value are superimposed, and the reverse active power regulation instruction is locked at the same time.

[0010] The primary frequency modulation function locking / superposition logic algorithm sets the system primary frequency modulation dead zone, adjustment difference parameters, channel opening logic algorithm and response amplitude.

[0011] The frequency monitoring module is used to monitor the real-time frequency of the power grid. 104+ is connected to the input port of the remote control device, and 104- is connected to the input port of the host. The frequency monitoring module is equipped with a fault recording device to record the number of actions, response time and modulation error waveform of a frequency modulation response action event. The recorded data content includes the current system frequency, total active power and other related information.

[0012] The fault recording device is a triggered fault recording device, including a frequency modulation trigger memory to record the number of response event actions; after the dedicated channel is started, the first adjustment feedback value received by the measurement and control data acquisition device is the number of actions, threshold value and reported active power curve prediction data.

[0013] The energy storage device is connected between the host output port and the dedicated channel, and corrects the host point table and uploads the real-time active value; a frequency modulation determination logic is added, and the dedicated channel point table reception is closed during normal operation, and the dedicated channel is enabled when the frequency monitoring module detects that the system frequency reaches the action threshold.

[0014] A primary frequency modulation load shedding operation topology device, comprising:

[0015] a memory storing a computer program;

[0016] A processor executes the computer program.

[0017] Wherein, when executing the computer program, the processor implements the steps of any topological structure.

[0018] A computer storage medium stores a computer program, and when the computer program is executed by a processor, the steps of a primary frequency modulation and load reduction operation topology structure are implemented.

[0019] The present invention has the following beneficial effects and advantages:

[0020] According to the national standard requirements, the present invention conducts an in-depth analysis of the technical solution for realizing the primary frequency modulation function of the photovoltaic power station, and optimizes the topological structure and corresponding hardware equipment of the photovoltaic power station. The present invention is aimed at the power control mode of the photovoltaic power station, enhances the load reduction level of the photovoltaic power station, enables the photovoltaic power station to participate in the primary frequency modulation of the system, reduces the change of the system frequency, and improves the stability of the power output; shortens the time loss caused by the data transmission volume, effectively improves the system response adjustment time, and has strong practicality.

[0021] The present invention also has the following functions and effects:

[0022] 1. The primary frequency modulation active power-frequency characteristics adjust the active power output value of the photovoltaic power station to achieve a fast frequency response function. The dead zone, modulation rate and power response amplitude during the primary frequency modulation are adjustable.

[0023] 2. When the frequency modulation is triggered once, it is in full lock operation.

[0024] 3. One-step frequency modulation for quick response.

[0025] 4. It has data monitoring and wave recording functions, which can record the grid connection point information of the photovoltaic power station and the operating status and feedback of the inverter during the primary frequency modulation in real time.

[0026] 5. Monitor the grid frequency.

[0027] 6. Determine whether the grid frequency has reached the frequency regulation range and whether the system frequency has reached the action threshold.

[0028] 7. Recording function: record the total number of actions, total action time and other information of fast frequency response.

[0029] 8.Simulation test function: It has fast frequency response simulation test function, simulates the frequency change of power grid, and tests the fast response function of primary frequency modulation.

[0030] 9. Data upload function: The number of rapid frequency response actions, action data and related telemetry, telesignaling and fault information should be uploaded to the upper level system. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0032] Figure 1 This is a topological diagram of the primary frequency modulation locking operation of the present invention;

[0033] Figure 2 This is the input and output wiring diagram of the frequency monitoring module of the present invention. DETAILED DESCRIPTION

[0034] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0035] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0036] Refer to the following Figure 1 and Figure 2 The technical solutions of some embodiments of the present invention are described.

[0037] Example 1

[0038] The present invention is a primary frequency regulation load shedding operation topology structure, such as Figure 1 As shown, Figure 1 This is a topological diagram of the primary frequency modulation interlocking operation of the present invention, as shown by the bold arrow part in the figure.

[0039] The primary frequency modulation and load reduction operation topology structure of the present invention is applied to a photovoltaic power station, and comprises: a frequency monitoring module, a primary frequency modulation and recording module, a dedicated channel and an energy storage device.

[0040] Specifically, the present invention connects a frequency monitoring module between the remote control device and the host, the output end of the frequency monitoring module is connected to the input end of the trigger fault recording device through a current input mode, and the triggering action process is fed back to the fault recording device through TCP104.

[0041] The end of the host is connected to the energy storage device cache unit through a dedicated channel, and the output end of the energy storage device is connected to the load and the power grid.

[0042] The present invention has a primary frequency modulation channel trigger mechanism, a primary frequency modulation locking operation function, a load reduction operation function, a primary frequency modulation frequency detection and judgment trigger and a primary frequency modulation fast response adjustment channel, which can improve the primary frequency modulation load reduction level and static characteristic output.

[0043] Compared with the traditional topology structure, the present invention adds a frequency monitoring module and a system primary frequency regulation locking / superposition logic algorithm. When it is detected that the grid frequency exceeds the primary frequency regulation threshold, the frequency regulation amount and the active power regulation value are superimposed, and the reverse active power regulation instruction is locked at the same time.

[0044] The present invention reserves a dedicated channel for primary frequency modulation, optimizes the message polling mechanism, and only uploads real-time active power when triggered, coexists with the original upload channel. The measurement and control data acquisition device has a reserved port that can be directly connected to the control system, and no CPU and connection port are reserved. A dedicated channel trigger judgment program is added to judge whether the power grid frequency reaches the primary frequency modulation range as the basis for starting the dedicated channel.

[0045] The present invention also adds a primary frequency modulation recording module to improve the related telemetry and telesignaling. A primary frequency modulation trigger memory is added to record the number of response event actions. After the dedicated channel is started, the first adjustment feedback value received by the measurement and control data acquisition device is the number of primary actions, threshold value, and reported active power curve prediction and other related data.

[0046] The present invention also adds an energy storage device, and uses a frequency modulation module. When the grid frequency increases, the electric energy of the limited inverter unit is stored in the energy storage device. Of course, the increase in system frequency is only a small probability event, and other storage methods can be set. When the grid frequency decreases, energy is released and the active power output capacity is quickly increased.

[0047] Example 2

[0048] This embodiment provides a primary frequency modulation and load reduction operation topology structure. In addition to the technical features of the above embodiments, this embodiment further includes the following technical features.

[0049] 1. A frequency monitoring module is installed between the telecontrol device and the host to monitor the real-time frequency of the power grid. 104+ is directly connected to the input port of the telecontrol device and 104- is connected to the input port of the host.

[0050] 2. The host adds the primary frequency modulation function blocking / superposition logic algorithm, sets the system primary frequency modulation dead zone, adjustment difference parameters, channel opening logic algorithm and response amplitude.

[0051] 3. The frequency monitoring module is equipped with a triggered fault recording device to record the number of actions, response time and modulation error waveform of a frequency modulation response action event. The recorded data includes the current system frequency, total active power and other related information.

[0052] 4. Add an energy storage device at the end of the host, connect the host output port to the dedicated channel, and modify the host point table to only upload the real-time active value, and add a frequency modulation judgment logic. During normal operation, close the dedicated channel point table reception, and enable the dedicated channel when the frequency monitoring module detects that the system frequency reaches the action threshold.

[0053] 5. Add protection and alarm functions to provide necessary protection alarm signals for rapid response to primary frequency modulation to prevent false operation caused by instantaneous frequency mutations due to sampling abnormalities, voltage fluctuations, single short circuits, etc.

[0054] Example 3

[0055] This embodiment provides a primary frequency regulation and load reduction operation topology structure, which is applicable to the primary frequency regulation of a photovoltaic power station. Specifically, it includes the following steps:

[0056] Step 1. Add frequency monitoring module;

[0057] Step 2. Add switches and connection ports, and modify the point table to real-time active power;

[0058] Step 3. Add energy storage device;

[0059] Step 4. Add a fault recording device;

[0060] Step 5. The communication method between the energy storage device and the host may be inconsistent with the original communication method.

[0061] The topological method of this embodiment adopts the primary frequency modulation and load reduction operation topological structure as described in any embodiment of the present invention, which has all the beneficial effects as described in any embodiment of the present invention.

[0062] Example 4

[0063] This embodiment provides a topology device, including: a memory storing a computer program; and a processor executing the computer program.

[0064] Wherein, when executing the computer program, the processor implements the steps of the topological method as described in any embodiment of the present invention.

[0065] The topological device of this embodiment adopts the topological method as described in any embodiment of the present invention, and has all the beneficial effects as described in any embodiment of the present invention.

[0066] Example 5

[0067] Based on the same inventive concept, an embodiment of the present invention further provides a computer storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of a primary frequency modulation and load reduction operation topology method described in Example 3 are implemented.

[0068] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0069] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0070] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0071] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A primary frequency modulation load shedding operation topology structure, comprising a host, characterized in that: A frequency monitoring module is connected between the host and the telecontrol device, and the output end of the frequency monitoring module is connected to the input end of the trigger-type fault recording device through a current input mode, and the triggering action process is fed back to the fault recording device through TCP104; the end of the host is coupled to the energy storage device cache unit through a dedicated channel, and the output end of the energy storage device is connected to the load and the power grid; the topological structure is also provided with a measurement and control digital acquisition device, and the measurement and control digital acquisition device is provided with a reserved port to connect the control system; the measurement and control digital acquisition device is provided with a dedicated channel trigger judgment program to judge whether the power grid frequency reaches the primary frequency modulation range as a basis for judging the start of the dedicated channel; the dedicated channel is a dedicated channel for primary frequency modulation, which optimizes the message polling mechanism and uploads real-time active power when triggered; the frequency monitoring module includes a system primary frequency modulation function blocking / superposition logic algorithm, when it is detected that the power grid frequency exceeds the primary frequency modulation threshold, the frequency adjustment amount and the active power adjustment value are superimposed, and the reverse active power adjustment instruction is locked at the same time; the primary frequency modulation function blocking / superposition logic algorithm sets the system primary frequency modulation dead zone, adjustment difference parameter, channel opening logic algorithm and response amplitude; The frequency monitoring module is used to monitor the real-time frequency of the power grid, connect 104+ to the input port of the telecontrol device, and connect 104- to the input port of the host; The frequency monitoring module is equipped with a fault recording device to record the number of actions, response time and adjustment difference waveform of a frequency modulation response action event, and the recorded data content includes the current system frequency and total active power information; the fault recording device is a trigger-type fault recording device, including a frequency modulation trigger memory, which records the number of response event actions; after the dedicated channel is started, the first adjustment feedback value received by the measurement and control data acquisition device is the number of actions, threshold and reported active power curve prediction data; The energy storage device is connected between the host output port and the dedicated channel, and corrects the host point table and uploads the real-time active value; a frequency modulation determination logic is added, and the dedicated channel point table reception is closed during normal operation, and the dedicated channel is enabled when the frequency monitoring module detects that the system frequency reaches the action threshold.

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