Prevent Power Outages: South Network Builds a Strong Grid

Since October 25, after receiving the State Electricity Regulatory Commission issued the "Opinions on Strengthening Power Safety Work to Prevent Large-scale Power Outages in the Power Grid" (hereinafter referred to as "Opinions"), the China Southern Power Grid Corporation, which regards the safety and stability of the power grid as its lifeline, will In less than 10 days, it promptly organized the interpretation of the 26 items listed in the Opinions concerning its own work, combined with the “Opinions” requirement to conduct in-depth analysis of potential large-scale power outages from 11 aspects. 36 measures to prevent and control large-scale blackouts were carried out.

In addition, in addition to collating the implementation of various work and measures, China Southern Power Grid Company, in accordance with the combination of the recent and long-term plans, made overall arrangements and adopted effective measures to ensure the effective implementation of all work.

"We will establish a sound long-term mechanism to prevent large-scale power outages in accordance with the requirements of the "Opinions" and resolutely put an end to the large-scale power outages in the power grid," said the person in charge of the Safety Supervision Department of the China Southern Power Grid Corporation.

Comprehensive analysis of risks

In July, two major power outages in India not only caused global hot debate, but also caused serious concern for China Southern Power Grid Corporation. With the issuance of the "Opinions," China Southern Power Grid attaches great importance to the rapid organization, deployment, and orderly implementation and promotion of various tasks.

In accordance with the Opinions requirements, China Southern Power Grid first comprehensively reviewed the risks faced by China Southern Power Grid in terms of structure, energy and load distribution, and grid operation modes. The comprehensive analysis makes South Net clearly identify the six types of AC and DC systems they face, the risk of the receiving end of the grid, equipment overload or failure, secondary systems, severe natural disasters, and six types of urban areas in key urban centers and regional power grid structure. risk.

"Through comprehensive risk assessment, according to the principle of stratification, classification, classification, and professionalism, we have formulated targeted control measures to ensure the safe and stable operation of the power grid," said the person in charge of the Safety Supervision Department of China Southern Power Grid Corporation.

The above-mentioned person in charge said that the targeted control measures are in fact the construction of the “three lines of defense” for dispatching operation management, risk management and control, and safety management of primary equipment and secondary systems and grid security.

Enhancing dispatch operation control management is the key to ensuring the safe operation of the power grid. With regard to the status of many heavy-loaded equipment, especially the full transmission of the West-to-East power transmission channel, China Southern Power Grid emphasizes that it must strictly comply with the requirements of the Guidelines for Safety and Stability of Electric Power Systems. From the refinement of measures, training of personnel, to the discipline of disciplines, strict measures have been formulated.

The construction of the “three lines of defense” for the safe and stable operation of primary equipment and secondary systems and grid security concerns the overall situation of the power grid. For this reason, China Southern Power Grid Company not only carried out special patrols on important equipment and access roads, but also increased power facilities. The protection against external force damage has led to the breakdown of important lines, and the specification for secondary network entry detection has also been developed, and network detection has been carried out. More importantly, the third line of defense has been established on the basis of real-time monitoring of the first and second lines of defense. The daily reporting mechanism of the situation monitors and sends the daily “three defense lines” operation status and promotes the “three defense lines” for real-time monitoring.

After conducting a comprehensive analysis, combing, and formulating measures for its own risks, China Southern Power Grid has strengthened its safety operation management and emergency management at the power-use side and power-generation side, and at the same time, it has completed the preparation of an orderly power utilization plan to further improve the treatment of hidden troubles. The quality of work puts forward more stringent requirements for itself.

In-depth study of fearless AC-DC hybrid operation

The “eight-to-five-straight” West-to-East power transmission channel has a maximum transmission capacity of 24,550 megawatts. The main grid uses AC-DC hybrid operation. China Southern Power Grid has become one of the most complex grids in the world.

The complex nature of the South China Power Grid is accompanied by the risk of a large-scale blackout. “Southern China Power Grid feeds multiple DCs into the Pearl River Delta region. Because of the electrical distance at the end point, serious failure of the AC power system at the receiving end may result in the failure of multiple DC commutation failures or even blocking at the same time,” said the person in charge of the China Southern Power Grid Safety Supervision Department.

To this end, China Southern Power Grid has conducted in-depth studies on the operational characteristics of AC-DC power transmission systems, and has carried out a lot of meticulous work from the following three aspects: strengthening the operation and maintenance of key plant stations, optimizing the coordination logic of AC-DC control protection systems, and improving the dynamic support capability of the receiving end voltage.

In the aspect of strengthening the operation and maintenance of key plant stations, China Southern Power Grid has established special dimension plans for DC converter stations and transmission lines to reduce the probability of equipment failures; at the same time, it has sorted out the sites where failures in the receiving end AC system may lead to multiple DC commutation failures. Teve measures for protection and switching ensure that the protection and switch can be quickly and reliably cut off.

On the other hand, the logic of AC/DC control and protection system coordination has been optimized. Optimize the control logic and parameters of the DC control system to reduce the chance of DC commutation failure at the same time, prevent DC protection from malfunctioning in the transient process of AC faults; comprehensively sizing and optimizing AC line distance from the protection action time of segment II to shorten backup protection removal faults time.

In order to improve the dynamic support capability of the receiving end voltage, China Southern Power Grid vigorously carried out trial application and promotion of the new type of dynamic reactive power supplement device (STATCOM) to improve the voltage support capability during faults.

According to reports, the 200 kilovolt STATCOM device at 500 kV Dongguan station has been put into formal operation. In 2013, STATCOM devices will be installed at 500 kV water town, kapok and northern suburbs to further improve the failure of the receiving end AC system. Voltage support capability.

Strengthen the strong base construction and strengthen the South

While implementing the "Opinions," China Southern Power Grid Corporation has comprehensively reviewed its work in the responsibility system for production safety, power grid structure, dispatch management, hidden trouble management, and emergency management. In accordance with the principle of checking missing defects and deepening management, China Southern Power Grid has identified each The objectives and requirements of the project also propose a mid- and long-term measures plan.

In respect of safety production, the person in charge of the Safety Supervision Department of China Southern Power Grid Company stated that it will unremittingly focus on the basic work of safety production as a key point for preventing power outages in large areas of the power grid, and through integrated management work, improve the mechanism, and implement it well. Improve safety production management.

In terms of power grid structure, in addition to including the demonstration of energy grid resilience analysis into the feasibility study of power transmission and transformation projects, the company will implement a power grid plan to guide the rational distribution of power supplies and improve the resilience of the power grids. It also addresses the characteristics of natural disasters with different typhoons and ice disasters. Improve the anti-platform and anti-icing design standards for the line; focus on accelerating the research and development of the electromagnetic ring network and promote the power supply in the load center area; study and formulate line design standards for multi-circuit lines on the same tower and the same corridor; and prevent voltage collapse and chain tripping accidents. And other issues.

“We will start at the source, work on prevention, adjust ideas especially on planning, increase research on technology, and strive to build a strong grid,” said the person in charge.

While building a strong power grid, China Southern Power Grid Corporation will strive to increase the risk management and control of power grids, and comprehensively improve the ability to control AC-DC hybrid operation and large-capacity transmission grids in terms of risk assessment and control, improvement of dispatching control capabilities, and research on islanding operation technologies. .

To this end, China Southern Power Grid has formulated a comprehensive and detailed mid- and long-term plan, including: continue to optimize the risk assessment mechanism of the power grid, improve the functions of the integrated defense system and basic data management, and improve the analysis and control of the dispatcher on the real-time security and stability of the power grid operation. Ability to speed up the research and development or the introduction of medium and long-term process analysis, electromechanical electromagnetic transient hybrid simulation, and voltage stability analysis tools applicable to the China Southern Power Grid, study of the medium- and long-term development of the power grid partition scheme and target grid, in-depth study of DC islanding technology, and new construction DC system islanding operation.

"In the future, we will do a good job in the implementation of various tasks and ensure the quality of work. We will integrate all work into the systems, standards, and processes for work safety, and further standardize the work safety management of the company's systems. Further deepen the construction and promotion of safety production risk management systems, strengthen advance prevention and control of safety risks, and do a good job in pre-event, post-event, post-event safety management, and strengthen safety control of the power grid.” Indicated.