Recently, the draft of the national standard plan "Technical Regulations for Wind Farm Access to Power System Part II: Offshore Wind Power", drafted by China Electric Power Research Institute and under the jurisdiction of 524 (China Electricity Council), has been prepared and is now open for public comment.
On January 1, 2006, GB Z 19963-2005 "Technical Regulations on Wind Farm Access to Power System" was implemented, which refers to the industry or enterprise standards of Denmark, Germany, the United Kingdom and other countries on wind farm access to power system, considering the development of wind power and the actual situation of the power system in China at that time, and put forward some principled provisions on the technical requirements for wind farm access to power system. In order to adapt to and support the national demand for the construction of million kilowatts and tens of millions of kilowatts of wind power bases, the revision of the GB Z 19963-2005 guiding document was launched in 2009, and on December 30, 2011, GB T 19963-2011 "Technical Regulations for Wind Farm Access to Power System" was approved and issued, and was officially implemented on June 1, 2012. and dispatching and operation, which supports the export and international standardization of China's wind power equipment.
During the 14th Five-Year Plan period, China's installed offshore wind power capacity grew rapidly, and by the end of 2022, the cumulative installed capacity of offshore wind power was 30.51 million kilowatts, ranking first in the world. According to the 14th Five-Year Plan for Modern Energy System released by the National Energy Administration, the installed capacity of offshore wind power will reach 71 million kilowatts by 2035. The "14th Five-Year Plan" will focus on the construction of five 10 million kilowatt offshore wind power bases in the Shandong Peninsula, the Yangtze River Delta, southern Fujian, eastern Guangdong and the Beibu Gulf, and promote the centralized and contiguous development of a number of key projects of the million kilowatt level. According to the current situation of China's offshore wind power development and the specific problems of grid-connected operation, in order to further adapt to the friendly grid-connected wind power under the new situation, ensure the safe and stable operation of large-scale offshore wind power access to the power system, and support the sustainable development of offshore wind power in China, the National Electric Power Regulatory Standardization Technical Committee organized China Electric Power Research Institute and other units to compile the technical specifications of "Technical Regulations for Wind Farm Access to Power System Part II: Offshore Wind Power", which provides a technical specification for the large-scale development of offshore wind power. Grid connection provides design guidance and technical specifications.
This standard aims at the challenges of large-scale offshore wind power grid connection, according to the current status of offshore wind power development in China and the specific problems of grid-connected operation, combined with GB T 199631 Technical Regulations for Wind Farms Connected to Power System Part I: Onshore Wind Power, which puts forward the technical requirements for active power, reactive power, inertia response and primary frequency modulation, reactive voltage control, fault ride-through, black start, operation adaptability, power, power quality, model and parameters, secondary system, test evaluation and system for offshore wind farms.
The subject chapter of this standard is divided into 16 chapters: it is composed of scope, normative reference documents, terms and definitions, general requirements, active power, inertia response and primary frequency modulation, reactive capacity, reactive voltage control, AC fault ride-through, DC transmission line fault response, black start, operation adaptability, power, power quality, model and parameters, secondary system, test evaluation and system, etc. There are 3 chapters of appendices, Appendix A: Description of Response Performance Indicators of Control System;Appendix B: Recommended Control Mode for Active Power in Offshore Wind Farms;Appendix C: Example curves of offshore wind power through primary frequency modulation through a flexible DC grid-connected system.
1) Chapter 1 is the object and scope of the standard. GB T 19963-2011 stipulates the technical requirements for wind farms to connect to the power system, and according to the standard formulation and revision plan issued by the Standardization Administration of the People's Republic of China in 2018, the revised GB T 19963 will be divided into two standards: "Technical Regulations for Wind Farms Connected to Power System Part I: Onshore Wind Power" and "Technical Regulations for Wind Farms Connected to Power System Part II: Offshore Wind Power". This standard specifies the technical requirements for the connection of offshore wind farms to the power system.
This document applies to new construction or renovation (expansion) of offshore wind farms connected to the power system through flexible DC transmission. For offshore wind farms connected to the power system via AC transmission, GB T 199631.
2) Chapter 2 is a normative reference document, citing a total of 17 relevant regulations and standards, and clearly defining the relevant references in the following text to avoid confusion.
3) Chapter 3 contains terms and definitions.
4) Chapter 4 stipulates the active power regulation function that offshore wind power should have through the flexible DC grid-connected system, and the offshore wind power through the flexible DC grid-connected system should be able to realize the continuous smooth adjustment of active power and participate in the active power control of the power system.
5) Chapter 5 stipulates that offshore wind power should have the inertia response and primary frequency modulation functions that the flexible DC grid-connected system should have, and the inertia response and primary frequency modulation functions can be enabled and disabled according to the actual needs of the power system, and the enabling and deactivating functions can be switched remotely and locally. This article stipulates that the inertia response and primary frequency modulation activation status signal and action status signal shall be set up for the offshore wind power grid-connected system through flexible DC, and the signal shall be uploaded to the dispatching and monitoring system.
6) Chapter 6 stipulates the reactive capacity requirements for offshore wind power through flexible DC grid-connected systems, including technical requirements such as reactive capacity configuration and adaptability of onshore flexible DC converters, offshore flexible DC converters, wind turbines in offshore wind farms, shunt capacitors, shunt reactors, static reactive power compensators, and static var generators.
7) Chapter 7 stipulates that the onshore converter station of offshore wind power through the flexible DC grid-connected system shall be equipped with a reactive voltage control system, which shall have the ability of reactive power regulation and voltage control.
8) Chapter 8 stipulates the fault ride-through capacity requirements for onshore converter stations, offshore converter stations, and offshore wind farms through flexible DC grid-connected systems, including low-voltage ride-through capacity and high-voltage ride-through capacity. When the voltage of the grid-connected point is within the specified range, the offshore wind power should be able to operate continuously through the flexible DC grid-connected system without going off the grid, and when the voltage of the grid-connected point is outside the specified range, the offshore wind power can stop running through the flexible DC grid-connected system.
9) Chapter 9 stipulates the DC line fault response requirements and treatment strategies for offshore wind power through the flexible DC grid-connected system, and the DC transmission cable faults are treated as permanent faults, and the treatment strategies are different according to the different DC wiring methods.
10) Chapter 10 stipulates the requirements for the ability of offshore wind power to start through the black start of the flexible DC grid-connected system, and realize the self-start of the offshore side system through the onshore side.
11) Chapter 11 stipulates the voltage adaptability, frequency adaptability and broadband oscillation technical requirements of onshore converter stations, offshore converter stations and offshore wind farms of offshore wind power through flexible DC grid-connected systems.
12) Chapter 12 specifies the technical requirements for the power of offshore wind farms.
13) Chapter 13 stipulates the power quality requirements for onshore converter stations, offshore converter stations, and offshore wind farms of offshore wind power through flexible DC grid-connected systems, including voltage deviation, flicker, harmonics, voltage imbalance, monitoring and governance, etc.
14) Chapter 14 stipulates the electromechanical transient and electromagnetic transient models and parameter requirements for offshore wind power through flexible DC grid-connected systems, and the model shall be verified, and the accuracy of the model shall be verified and evaluated.
15) Chapter 15 specifies the technical requirements for the secondary system of offshore wind power through flexible DC grid-connected systems.
16) Chapter 16 stipulates that a test and evaluation report shall be provided before offshore wind power is connected to the power system through a flexible DC grid-connected system.
This standard unifies the technical requirements for offshore wind power access to the power system, which is conducive to improving the safe and stable operation of the offshore wind power grid-connected system in the temporary steady state, and is of great significance for large-scale offshore wind power development, reliable power supply in the eastern coastal area, and improving economic benefits.
This standard helps the implementation of the "double carbon" goal, improves the overall energy efficiency level of the society, and promotes energy conservation and emission reduction in the whole societyImproving the safety and economy of power grid operation will help ensure the safe and efficient operation of the power system.