New energy primary frequency modulation control system

Abstract

The invention discloses a new energy primary frequency modulation control system, and relates to the field of new energy, and the system comprises a frequency measurement device and a frequency modulation control device. The frequency measuring device is used for collecting the electrical quantity of a grid-connected point; the electrical quantity comprises a power grid frequency; the frequency modulation control device is connected with the frequency measurement device, the wind turbine generator / photovoltaic inverter and the dispatching center, and is used for acquiring operation data of the wind turbine generator / photovoltaic inverter, receiving a target instruction of the dispatching center, performing frequency modulation control according to the power grid frequency, the operation data and the target instruction, and performing AGC control according to the target instruction; and the AGC control comprises AGC active control and start / stop control. The system can be matched with a wind turbine generator / photovoltaic inverter, a booster station integrated automation system, an AGC system and the like of a new energy station to complete a fast frequency response function of the new energy station.

Description

Technical Field

[0001] The present application relates to the field of new energy, and in particular to a new energy primary frequency modulation control system. Background Art

[0002] Frequency is one of the most critical operating parameters of a power system, and frequency fluctuations have a significant impact on its safe and stable operation. While interconnected power systems enhance their ability to withstand active power surges, they also increase the potential for active power imbalances, further posing challenges in maintaining grid and frequency stability. Maintaining grid frequency within the required range under the influence of disturbances is one of the primary objectives for safe and stable power system operation.

[0003] The rapid development of new energy stations in recent years has squeezed the space for conventional power units with rotational inertia, the power grid's primary frequency regulation resource reserves have declined, and the power grid's anti-disturbance ability has been greatly reduced. Against the special background of the current ultra-high voltage AC / DC hybrid and the continuous expansion of DC transmission scale, new energy units do not have primary frequency regulation capabilities, resulting in the increasingly apparent structural dilemma of power grid frequency control. There is an urgent need for new energy units to participate in the rapid response control of large power grid frequencies and improve the power grid's safe and stable operation capabilities. Summary of the Invention

[0004] The purpose of this application is to provide a new energy primary frequency regulation control system that can cooperate with the wind turbine / photovoltaic inverter, booster station integrated automatic system and AGC system of the new energy station to complete the rapid frequency response function of the new energy station.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] A new energy primary frequency modulation control system, comprising: a frequency measuring device and a frequency modulation control device;

[0007] The frequency measuring device is used to collect electrical quantities at the grid connection point; the electrical quantities include the grid frequency;

[0008] The frequency modulation control device is connected to the frequency measuring device, the wind turbine generator set / photovoltaic inverter and the dispatching center, and is used to obtain the operating data of the wind turbine generator set / photovoltaic inverter, receive the target instructions from the dispatching center, perform frequency modulation control according to the grid frequency, the operating data and the target instructions, and perform AGC control according to the target instructions; the AGC control includes AGC active power control and start / stop control.

[0009] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0010] The present application provides a new energy primary frequency regulation control system, which collects the electrical quantity of the grid connection point in real time through a high-precision frequency measuring device, monitors the grid frequency in the electrical quantity in real time through a frequency regulation control device, cooperates with wind turbines / photovoltaic inverters, booster station integrated automatic systems, etc., to complete unified coordinated control with the AGC function and realize a fast frequency response function. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. 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 creative work.

[0012] Figure 1 A schematic diagram of a module of a new energy primary frequency modulation control system provided in one embodiment of the present application;

[0013] Figure 2 This is an application diagram of a new energy primary frequency modulation control system;

[0014] Figure 3 This is another application diagram of the new energy primary frequency modulation control system;

[0015] Figure 4 This is the principle block diagram of the main control module in the frequency measurement device;

[0016] Figure 5 This is the principle block diagram of the telemetry module;

[0017] Figure 6 This is a schematic diagram of the active power-frequency droop characteristic curve of the wind farm's fast frequency response;

[0018] Figure 7 This is a schematic diagram of the active power-frequency droop characteristic curve of a photovoltaic power station with fast frequency response;

[0019] Figure 8 Schematic diagram of the frequency step disturbance adjustment process for fast frequency response of new energy stations. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described 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 efforts are within the scope of protection of this application.

[0021] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0022] like Figure 1 As shown, in an exemplary embodiment, a new energy primary frequency modulation control system is provided, including: a frequency measuring device 1 and a frequency modulation control device 2. Figure 1 As shown, the system further includes a monitoring workstation 3. The frequency measuring device 1 and the monitoring workstation 3 are both connected to the frequency modulation control device 2.

[0023] The frequency measuring device 1 is used to collect electrical quantities at the grid connection point; the electrical quantities include the grid frequency.

[0024] The frequency modulation control device 2 is connected to the wind turbine / photovoltaic inverter and the dispatching center, and is used to obtain the operating data of the wind turbine / photovoltaic inverter, receive the target instructions of the dispatching center, and perform frequency modulation control and AGC control based on the target instructions according to the grid frequency and the operating data; the AGC control includes AGC active power control and start / stop control.

[0025] The monitoring workstation 3 is used to monitor, configure and maintain the new energy primary frequency modulation control system.

[0026] The new energy primary frequency regulation control system software integrates the AGC active power automatic control function, and cooperates with the wind turbine / photovoltaic inverter, booster station integrated system and automatic generation control (AGC) system of the new energy station to complete the unified coordinated control with the AGC function and realize the fast frequency response function. In order to meet the access requirements of the power grid dispatching master station, typical application solutions are as follows Figure 2-Figure 3 shown.

[0027] Furthermore, the frequency measuring device 1 is used to collect various electrical quantities including the grid frequency at the grid connection point. In order to ensure the real-time data refresh, the relevant electrical quantity data is directly calculated by sampling the PT and CT AC signals at the grid connection point. At the same time, the data is sent to the frequency modulation control device to ensure transmission without dead zone changes.

[0028] Specifically, the high-precision frequency measurement device 1 is a new generation of high-precision electrical quantity measurement and recording devices. It enables high-precision measurement and complete recording over the entire time period, without missing any data points. It displays the full range of measured and recorded parameters, including current, voltage, and frequency, as well as derived electrical quantities like power and related non-electrical quantities. Adapting to the evolving needs of power systems and meeting the technical requirements for transient fault recording and steady-state recording devices, the device provides data in the standard COMTRADE format specified in IEC60255-24:2001, facilitating data exchange with other devices.

[0029] The frequency measuring device 1 adopts a 19-inch 2U aluminum alloy chassis and consists of a main control module, a measurement module (standard 6-channel voltage and 6-channel current measurement, expandable) and a dual-channel power supply module.

[0030] The measuring module is used to collect the electrical quantity of the grid-connected point; the main control module is connected to the measuring module and the frequency modulation control device, and is used to send the electrical quantity to the frequency modulation control device; the dual-channel power supply module is connected to the measuring module and the main control module, and is used to supply power to the measuring module and the main control module.

[0031] The main control module uses FPGA high-speed chip processing to achieve high-precision data collection and real-time time-stamped transmission. The coefficients and power synthesis of electrical quantity data can be freely combined. It communicates with the frequency modulation control device 2 through 1000M Ethernet. The frequency modulation control device 2 compresses and stores the collected data throughout the process and performs corresponding recording analysis. Figure 4 This is the principle block diagram of the main control module. Figure 5 This is the principle block diagram of the telemetry module.

[0032] The information collected by the frequency measuring device 1 includes:

[0033] Telemetry: grid frequency, grid connection point power, voltage, current, etc.

[0034] The performance of the frequency measuring device shall meet the following requirements:

[0035] Supports 6-channel voltage (rated 100V) and 6-channel current (rated 5A) signal input; power and other electrical quantity calculations can be freely combined according to the connection channels;

[0036] Sampling rate 10,000 times / second;

[0037] Frequency detection accuracy: 0.003Hz;

[0038] Frequency measurement resolution: 0.002Hz;

[0039] Frequency measurement period: 10ms.

[0040] Furthermore, the frequency control device 2 realizes the data acquisition and control interface with the frequency measuring device 1, wind turbines / photovoltaic inverters, booster station integrated automatic system and AGC function and other related systems, receives the grid frequency and other electrical quantities of the grid connection point; collects the operating data of the wind turbines / photovoltaic inverters, receives the control target instructions of the dispatching center, and executes frequency control, AGC active power control and start / stop control.

[0041] When the grid frequency is normal, the frequency control device 2 calculates the frequency regulation power target value for each renewable energy generator based on the AGC command target value and issues the command to the generator communication unit via the integrated automation system and the AGC system. While responding to the AGC command, the frequency control device locks control and sends a reverse lock signal to the AGC system when the system frequency approaches the frequency limit to a certain level (with a configurable dead zone).

[0042] When the grid frequency exceeds the limit, the primary frequency regulation control system activates frequency response mode, calculates the current power increase or decrease based on the active power-frequency droop characteristic curve, and then superimposes the AGC command (algebraic sum) to obtain the overall regulated power. The power distribution model then determines the active power target value for each inverter, issues a command to the unit communication unit, and monitors the power regulation results within a specified time, forming a closed-loop control system. If the AGC command is inconsistent with the frequency regulation direction, a reverse blocking signal is sent to the AGC system.

[0043] Based on this, the frequency modulation control device 2 includes: a data acquisition unit, a frequency modulation control unit and an AGC control unit.

[0044] a data acquisition unit connected to the main control module, the wind turbine generator set / photovoltaic inverter, and the dispatching center, for acquiring operating data of the wind turbine generator set / photovoltaic inverter, receiving target instructions from the dispatching center, and for acquiring the electrical quantity of the grid connection point collected by the frequency measuring device;

[0045] a frequency modulation control unit, connected to the data acquisition unit, and configured to perform frequency modulation control according to the grid frequency, the operating data, and the target instruction;

[0046] An AGC control unit is connected to the data acquisition unit and is used to perform AGC control according to the target instruction.

[0047] Furthermore, the frequency modulation control unit includes:

[0048] A power target value calculation subunit for regulating power, configured to calculate the frequency regulation power target value of a single new energy generator set according to the target instruction when the power of the power grid is normal;

[0049] A first regulating subunit, connected to the regulating power target value calculating subunit, is used to regulate a single new energy generator set according to the frequency regulation power target value and send a reverse blocking signal to the AGC system;

[0050] The overall regulated power calculation subunit is used to calculate the current power increase or decrease according to the active power-frequency droop characteristic curve when the grid power exceeds the limit, and then add the target instruction to obtain the overall regulated power;

[0051] an active power target value determining subunit, connected to the overall regulated power calculating subunit, and configured to determine the active power target value of a single inverter based on the overall regulated power through a power allocation model;

[0052] The second regulating subunit is connected to the active power target value determining subunit, and is used to regulate the single inverter according to the active power target value and send a reverse blocking signal to the AGC system.

[0053] Furthermore, the FM control device 2 is based on a fully enclosed, fanless, embedded hardware platform running the Linux operating system, ensuring stable and reliable operation and incorporating hardware watchdog technology. Data storage utilizes a large-capacity storage disk, which, without the rotating parts of a mechanical hard drive, makes data storage more reliable.

[0054] To ensure reliable operation of the frequency modulation control device 2 and truly achieve disturbance-free switching between dual power supplies, a dual redundant power supply design is employed. Each power supply can operate independently or together, and each power supply can be either DC or AC. Isolation technology is employed to completely isolate the weak current system from the strong current system. High-performance EMI filters and a well-designed structure significantly enhance the device's electromagnetic compatibility.

[0055] In terms of software design, the running status monitoring and guarding functions of key processes are provided. In the case of abnormal running of the process, the software program can be automatically restarted to ensure the continuous and uninterrupted operation of the software program. The basic configuration of the frequency modulation control device 2 is shown in Table 1.

[0056] Table 1 Basic configuration of the device

[0057]

[0058]

[0059] like Figure 2-Figure 3 As shown, the frequency modulation control device 2 obtains the operating data of the wind turbine generator set through the energy management platform; the frequency modulation control device 2 obtains the operating data of the photovoltaic inverter through the communication unit.

[0060] The collected real-time operating data and control quantities of wind turbines / photovoltaic inverters include at least:

[0061] Telemetry: active power, reactive power, terminal voltage, current, power factor, wind speed, wind direction, converter temperature, etc.

[0062] Remote signaling: grid connection status, fault signal;

[0063] Remote control quantity: active power target value, reactive power target value.

[0064] The collected real-time operation data of the booster station shall include at least:

[0065] Telemetering: active power, reactive power, current, power factor, grid frequency at the grid connection point, bus voltage on the high and low voltage sides of the main transformer, active power, reactive power, current, power factor, tap position of the main transformer, active power, reactive power, current, power factor of the collector line;

[0066] Telesignal: switch and knife switch position signal.

[0067] Furthermore, the new energy primary frequency regulation control system has two control modes, namely AGC control mode and frequency regulation mode. In AGC mode, the dispatching instructions are executed to ensure that the active power output meets the dispatching requirements. In frequency regulation mode, the new energy primary frequency regulation control system automatically increases or decreases the active power output of the grid connection point according to the preset active power-frequency droop characteristic curve to achieve fast frequency response. The wind farm fast frequency response active power-frequency droop characteristic curve is as follows Figure 6 As shown, the fast frequency response active power-frequency droop characteristic curve of the photovoltaic power station is as follows Figure 7 shown.

[0068] Specific features include:

[0069] 1) According to the real-time operating status, the real-time power generation capacity of a single unit is adaptively calculated to obtain the real-time power generation capacity Pcap.

[0070] 2) The grid frequency changes beyond the set range, and the active output is greater than 10% P N When the active power is adjusted quickly, the fast frequency response is started.

[0071] 3) When the grid frequency is within the control dead zone, f d -~f d + (Wind farms can be set to 49.9-50.1Hz, and photovoltaic power plants can be set to 49.94-50.06Hz). Normal operation does not participate in frequency regulation, and a reserve capacity of 10% of the current generating capacity is reserved. Table 2 shows the fast frequency response parameters for new energy stations.

[0072] Table 2 New energy station fast frequency response parameters

[0073] parameter Fast frequency response dead zone (Hz) Fast frequency response limiting Adjustment rate photovoltaic power station ±0.06 ≥10%Pn 3％ wind farm ±0.1 ≥10%Pn 2％

[0074] In the event of a high-frequency disturbance in the power grid, the active power of the renewable energy station will no longer be adjusted downward when it drops to 10% of the rated load. When the grid frequency exceeds 50±0.1Hz, the renewable energy fast frequency response function will block the AGC reverse adjustment command.

[0075] 4) When the frequency exceeds the dead zone, f d -~f d +, the system calculates the active power target value based on the fast frequency response active power-frequency droop characteristic curve function:

[0076]

[0077] Where: f d For fast frequency response dead zone, P N Rated power, δ% new energy fast frequency response modulation rate; P0 initial value of active power.

[0078] 5) New energy stations shall be limited to no less than 10% of the rated load, and wind turbines shall not be disconnected from the grid or shut down due to rapid frequency response.

[0079] 6) The system integrates AGC automatic active power control function, fast frequency response and AGC unified coordinated control.

[0080] 7) The total active power control target value should be the algebraic sum of the AGC command value and the fast frequency response adjustment value. When the grid frequency exceeds 50±0.1Hz, the fast frequency response function blocks the AGC reverse adjustment command.

[0081] 8) Using a power allocation optimization algorithm that considers comprehensive factors such as the unit's real-time operating conditions, control characteristics, health status, and the on-grid electricity price of the unit at different times, the power target value P is allocated to a single inverter to obtain the power target value of a single unit.

[0082] 9) The system adopts direct communication with a single unit and uses multi-threaded parallel acquisition and parallel control technology to ensure the real-time refresh of operating data and active power control response.

[0083] The fast frequency response technical indicators of the new energy primary frequency modulation control system provided in this application are as follows:

[0084] like Figure 8 As shown in the figure, for a frequency step disturbance with a regulation change of not less than 10% of the rated output, the response process meets the following requirements:

[0085] Response delay time t hx: The time from when the frequency crosses the frequency regulation dead zone to when the power generation output starts to reliably change in the frequency regulation direction. For both wind power and photovoltaic power generation, this value should not exceed 2 seconds.

[0086] Response time t 0.9 : The time from when the frequency exceeds the frequency regulation dead zone until the active power regulation reaches 90% of the difference between the frequency regulation target value and the initial power. For wind power, this should not exceed 12 seconds; for photovoltaic power, this should not exceed 5 seconds.

[0087] Adjustment time t s : The minimum time from when the frequency exceeds the frequency regulation dead zone to when the active power reaches stability (power fluctuation does not exceed ±2% (wind power) or ±1% (photovoltaic) of the rated output). For both wind power and photovoltaic power, it should not exceed 15 seconds.

[0088] Furthermore, to ensure the safe and stable operation of the new energy station, a safety constraint check is performed during the primary frequency regulation operation, taking into account two sets of limit values: the lockout value and the limit value. If the safety check fails, the lockout control will be implemented and can only be released manually. The main safety constraints are:

[0089] Equipment failure or abnormality, communication failure or abnormality, system grounding failure, etc.

[0090] Voltage limit constraints for busbars at all levels in new energy stations;

[0091] Voltage mutation constraints on busbars at all levels in new energy stations;

[0092] Terminal voltage constraints for each unit;

[0093] The maximum active capacity and available active capacity constraints of each unit;

[0094] Temperature constraints for each unit converter.

[0095] The new energy primary frequency modulation control system provided in this application supports timed sampling and storage of historical data of telemetry, electric energy, etc. with time stamps. The data storage period is adjustable from 1 to 60 minutes and supports 3 different storage periods.

[0096] Frequency modulation control device 2 stores historical data on a high-capacity storage disk, ensuring data loss during power outages for at least 10 years. The storage capacity is at least 500GB and can be expanded as needed. Based on 4,000 telemetry measurements, 2,000 energy measurements, and a one-minute data storage cycle, the device can store at least 60 days of data.

[0097] On the monitoring workstation 3, historical data is stored on a hard disk. The storage capacity depends on the hard disk capacity. The high-speed sampling and recording data of the high-precision frequency measuring device are configured to support at least two years of historical data storage on the workstation's hard disk capacity.

[0098] The communication interfaces of the new energy primary frequency modulation control system provided in this application include:

[0099] 1) The network communication interface is used for communication with the unit, and the communication protocol uses MODBUS / TCP, IEC60870-5-104 protocol or PLC private protocol.

[0100] 2) Communication with the booster station integrated automatic system adopts serial port or network communication interface, and the communication protocol uses CDT, IEC60870-5-101 or IEC60870-5-104 protocol.

[0101] 3) Communication with the dynamic reactive power compensation device adopts a serial port or a network communication interface, and the communication protocol uses MODBUSTCP / RTU, CDT, IEC60870-5-101 or IEC60870-5-104 protocol.

[0102] 4) Use network communication interface with AGC system, and the communication protocol uses MODBUS TCP and IEC60870-5-104 protocol.

[0103] The new energy primary frequency modulation control system provided in this application can also perform image monitoring.

[0104] 1) The system can display data changes through curves, bar graphs, pie charts, and other display methods. Multiple curves can be drawn in different colors in the same window, and all curves are integrated into one chart. Various statistical values (average value, maximum value and occurrence time, minimum value and occurrence time, etc.) are also displayed. Real-time output, target value, power forecast value comparison, real-time and historical comparison curves, real-time and historical trend curves of collected data are provided.

[0105] 2) The collected power and frequency can be displayed as recorded waveforms, and the waveform display is consistent with the time-scale queue issued by the control command. The waveform can be synthesized from the control command with the consistent waveform to reflect the entire frequency modulation process.

[0106] 3) The system can realize manual switching of control modes through the human-machine interface provided by the monitoring workstation.

[0107] 4) The system has permission control function, and all manual operations have operation logs for reference.

[0108] 5) The system provides an interface to support the reading, modification and updating of system parameter configurations, including communication parameters, information point tables, safety constraints, dead zone ranges, timeout periods, etc.

[0109] 6) The system provides communication monitoring function for all communication interfaces (serial port, Ethernet port) of the device.

[0110] 7) The system provides alarm functions for the following events and exceptions, and provides storage and query functions for historical events:

[0111] Automatically issue a circular queue of control orders to increase, decrease or maintain holdings;

[0112] communication failure;

[0113] Device operating conditions, including restart, power failure, shutdown, etc.;

[0114] Device power supply failure information;

[0115] Device configuration changes;

[0116] Important events or abnormalities in the operation of the booster station related to AGC;

[0117] Important events or abnormalities in the operation of AGC-related equipment;

[0118] Automatic switching of control modes;

[0119] Control lockout and reasons;

[0120] Various manual operations.

[0121] The new energy primary frequency modulation control system provided in this application has the following characteristics:

[0122] 1) High reliability.

[0123] Both the frequency modulation control device 2 and the frequency measurement device 1 feature an embedded, low-power, fanless design. The frequency modulation control device utilizes a large-capacity storage disk, and the entire system has no rotating equipment. This system supports active / standby, dual-machine, dual-network redundancy, and power supply redundancy, resulting in high reliability. Communication between the frequency modulation control device 2 and the frequency measurement device 1 supports a dual-network architecture.

[0124] 2) High security.

[0125] The frequency modulation control device 2 based on the Linux operating system and the frequency measuring device 1 based on the single chip embedded system make the system powerful and reliable without worrying about virus attack.

[0126] 3) Provide multiple modes and user-customizable protection methods.

[0127] The system features multiple safety protections, including lockout alarms for communication interruptions, command deviations, voltage limits exceeding the machine end, bus voltage limits exceeding the bus limit, and relay control anomalies. The safety protection logic is well-designed and operates correctly, and its types can be increased, decreased, and customized based on user needs.

[0128] 4) Actively warn and detect abnormal situations as early as possible.

[0129] 5) High flexibility and high compatibility.

[0130] 6) Support mature and reliable communication protocols and good compatibility.

[0131] 7) The frequency measuring device 1 has a high-precision measurement function.

[0132] The frequency measuring device 1 is an intelligent device developed using FPGA high-speed chips (with receiving clock B code synchronization), which has high-precision voltage and power measurement and high-precision frequency measurement of n lines.

[0133] 8) Full raw data waveform recording

[0134] The system continuously records important electrical quantities such as voltage, current, and frequency, enabling comprehensive analysis. Data recording methods include full waveform recording, steady-state data recording, and transient data recording. The data files generated by these three types of recording can be named and stored separately, and all can be analyzed using device analysis software. Both steady-state and transient data are time-stamped. Raw data, acquired at a high-speed 10k sampling rate, is compressed and stored using a specialized high-compression algorithm.

[0135] 9) The system is highly intelligent.

[0136] Adopt intelligent adjustment strategy to prevent over-adjustment and reduce the impact on the unit.

[0137] Adopt intelligent precision adjustment strategy to achieve maximum adjustment accuracy.

[0138] A variety of intelligent power distribution strategies ensure regulation accuracy and optimal unit operation mode.

[0139] The self-learning method is used to dynamically correct the relationship between the frequency regulation target value and the active power output.

[0140] The performance indicators of the new energy primary frequency modulation control system provided in this application include:

[0141] (1) System reference specifications

[0142] DL / T 478—2001: General technical requirements for static relay protection and safety automatic devices;

[0143] DL / T 630—1997: Technical requirements for AC sampling telecontrol terminals;

[0144] DL 5003—2005: Design specification for power system dispatching automation;

[0145] DL / T 5226—2005: Technical regulations for the design of computer monitoring systems for power networks in thermal power plants;

[0146] GB / T 7261-2008: Basic test methods for relay protection and automatic safety devices;

[0147] GB / T 14598.301-2010: Technical requirements for microcomputer-based generator and transformer dynamic recording devices;

[0148] GB / T 19520.12-2009: Mechanical dimensions of electronic equipment, 482.6 mm (19 in) series;

[0149] GB / T 22386-2008: Common format for the exchange of transient data in power systems (IDT IEC 60255-22-6:2001);

[0150] GB / T 26864: Dynamic test of relay protection products for power systems;

[0151] DLT 553-2013: General technical requirements for power system dynamic recording devices;

[0152] DL / T 873-2004: Technical requirements for microcomputer-based dynamic recording devices for generator transformer groups;

[0153] DL / T 478-2001: General technical requirements for static relay protection and safety automatic devices;

[0154] DL / T 860: Substation communication networks and systems;

[0155] DL / T 995: Inspection procedures for relay protection and power grid safety automatic devices;

[0156] DL / T 1870: Technical Specification for Power System Grid-Source Coordination;

[0157] GB / T 19963: Technical regulations for wind farm integration into power systems;

[0158] GB / T 19964: Technical regulations for the connection of photovoltaic power stations to the power system.

[0159] (2) Control performance indicators

[0160] Fast FM response delay time: ≤2 seconds;

[0161] Fast frequency modulation control response time: wind power ≤ 12 seconds, photovoltaic ≤ 5 seconds;

[0162] Fast frequency adjustment completion time: ≤15 seconds;

[0163] Fast frequency modulation active power control deviation: wind power ≤ 2% Pn, photovoltaic ≤ 1% Pn;

[0164] Fast frequency modulation control cycle: ≤1s;

[0165] Frequency sampling period: 10ms;

[0166] Frequency detection accuracy: 0.003Hz;

[0167] Frequency measurement resolution: 0.002Hz.

[0168] (3) Measurement loop indicators

[0169] 1) Rated electrical parameters

[0170] Frequency FN: 50Hz;

[0171] AC current IN: 5A, 1A;

[0172] AC voltage UN: 57.7V, 100V.

[0173] 2) Accuracy

[0174] AC voltage loop accuracy, ≤0.2% at rated voltage;

[0175] AC current loop accuracy, ≤0.2% at rated current;

[0176] Frequency measurement accuracy: Under rated voltage, when the frequency is 40-55Hz, the measurement error does not exceed ±0.003Hz;

[0177] Power measurement accuracy: The power measurement error when rated voltage and rated current are applied is not greater than 0.5% of apparent power.

[0178] 3) Power consumption

[0179] AC current loop: when IN = 5A, each phase ≤ 1VA; when IN = 1A, each phase ≤ 0.5VA;

[0180] AC voltage circuit: at rated voltage, each phase shall not exceed 1VA;

[0181] 4) Sampling indicators

[0182] Sampling resolution: 16bit;

[0183] Sampling rate: 10kHz.

[0184] (4) Electrical indicators of the device

[0185] 1) Working power supply

[0186] AC and DC power supplies can achieve seamless switching and provide power supply status monitoring function;

[0187] AC power supply: AC220V±20%V, 50Hz; DC power supply: DC110 / DC220±20%V;

[0188] The power supply voltage range is 176-253V (Ui×%80~Ui×%115) without affecting the correctness of data transmission;

[0189] Power consumption of the whole machine: ≤100W.

[0190] 2) Device time synchronization

[0191] Support GPS and Beidou time synchronization;

[0192] Support IRIG-B code time synchronization;

[0193] Timing accuracy: ≤1uS.

[0194] 3) System load rate

[0195] CPU load rate (normal state) ≤ 25%;

[0196] CPU load rate (fault state) ≤ 50%;

[0197] LAN load rate ≤25%.

[0198] 4) Operational reliability

[0199] MTBF: >50,000 hours;

[0200] Maintenance MTTR: <0.5 hours;

[0201] Annual availability: ≥99.99%;

[0202] Service life: >15 years.

[0203] 5) Insulation performance

[0204] Insulation resistance:

[0205] The insulation resistance of the communication port to ground is ≥5MΩ;

[0206] The insulation resistance of the power port to ground is ≥5MΩ.

[0207] Dielectric strength:

[0208] Insulation strength of communication port to ground: no breakdown or flashover when 500V is applied;

[0209] Insulation strength of power port to ground: no breakdown or flashover when applying 1500V.

[0210] 6) Electromagnetic compatibility

[0211] Fast transient interference test: The device should be able to withstand the fast transient interference test with severity level IV specified in 4.1 of GB / T 14598.10-1996;

[0212] Electrostatic discharge test: The device can withstand the electrostatic discharge test of severity level IV specified in 4.2 of GB / T 14598.14-1998;

[0213] Pulse group interference test: The device can withstand the 1MHz and 100kHz pulse group interference test with a severity level of III as specified in 3.1.1 of GB / T 14598.13-1998;

[0214] Radio frequency electromagnetic field radiation immunity test: The device should be able to withstand the radio frequency electromagnetic field radiation immunity test with a severity level of III as specified in 4.1.1 of GB / T 14598.9-2002.

[0215] 7) Working environment

[0216] Working temperature: -25℃~55℃;

[0217] Storage temperature: -30℃~70℃;

[0218] Humidity: <95% (no condensation);

[0219] Transport: Complies with IEC60870-2-2 Class 2K4.

[0220] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0221] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A new energy primary frequency modulation control system, characterized in that: include: Frequency measuring device and frequency modulation control device; The frequency measuring device is used to collect electrical quantities at the grid connection point; the electrical quantities include the grid frequency; The frequency modulation control device is connected to the frequency measuring device, the wind turbine generator set / photovoltaic inverter and the dispatching center, and is used to obtain the operating data of the wind turbine generator set / photovoltaic inverter, receive the target instructions from the dispatching center, perform frequency modulation control according to the grid frequency, the operating data and the target instructions, and perform AGC control according to the target instructions; the AGC control includes AGC active power control and start / stop control.

2. The new energy primary frequency modulation control system according to claim 1 is characterized in that: Also includes: A monitoring workstation is connected to the frequency modulation control device and is used to monitor, configure and maintain the new energy primary frequency modulation control system.

3. The new energy primary frequency modulation control system according to claim 1 is characterized in that: The frequency measuring device includes: a main control module, a measuring module and a dual-channel power supply module; The measuring module is used to collect the electrical quantity of the grid connection point; The main control module is connected to the measurement module and the frequency modulation control device, and is used to send the electrical quantity to the frequency modulation control device; The dual-channel power supply module is connected to the measuring module and the main control module, and is used to supply power to the measuring module and the main control module.

4. The new energy primary frequency modulation control system according to claim 3 is characterized in that: The frequency modulation control device comprises: a data acquisition unit connected to the main control module, the wind turbine generator set / photovoltaic inverter, and the dispatching center, for acquiring operating data of the wind turbine generator set / photovoltaic inverter, receiving target instructions from the dispatching center, and for acquiring the electrical quantity of the grid connection point collected by the frequency measuring device; a frequency modulation control unit, connected to the data acquisition unit, and configured to perform frequency modulation control according to the grid frequency, the operating data, and the target instruction; An AGC control unit is connected to the data acquisition unit and is used to perform AGC control according to the target instruction.

5. The new energy primary frequency modulation control system according to claim 4 is characterized in that: The frequency modulation control unit includes: A power target value calculation subunit for regulating power, configured to calculate the frequency regulation power target value of a single new energy generator set according to the target instruction when the power of the power grid is normal; A first regulating subunit, connected to the regulating power target value calculating subunit, is used to regulate a single new energy generator set according to the frequency regulation power target value and send a reverse blocking signal to the AGC system; The overall regulated power calculation subunit is used to calculate the current power increase or decrease according to the active power-frequency droop characteristic curve when the grid power exceeds the limit, and then add the target instruction to obtain the overall regulated power; an active power target value determining subunit, connected to the overall regulated power calculating subunit, and configured to determine the active power target value of a single inverter based on the overall regulated power through a power allocation model; The second regulating subunit is connected to the active power target value determining subunit, and is used to regulate the single inverter according to the active power target value and send a reverse blocking signal to the AGC system.

6. The new energy primary frequency modulation control system according to claim 1, characterized in that: The frequency modulation control device obtains the operating data of the wind turbine generator set through the energy management platform; the frequency modulation control device obtains the operating data of the photovoltaic inverter through the communication unit.

7. The new energy primary frequency modulation control system according to claim 1, characterized in that: Safety constraint checks are performed during primary frequency regulation operation; safety constraint conditions include: Equipment failure or abnormality, communication failure or abnormality, and ground fault; Voltage limit constraints for busbars at all levels in new energy stations; Voltage mutation constraints on busbars at all levels in new energy stations; Terminal voltage constraints for each unit; Constraints on the maximum active capacity and available active capacity of each unit; Temperature constraints of each unit converter.

8. The new energy primary frequency modulation control system according to claim 1, characterized in that: The frequency modulation control device and the frequency measuring device are both embedded low-power fanless designs.

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