Yangtze River Delta power integration accelerated

Electricity comes first for urban development. Since the integrated development of the Yangtze River Delta region has become a national strategy, the integration of power in the Yangtze River Delta region has also been accelerated. Recently, State Grid Shanghai Qingpu Power Supply Company, State Grid Jiangsu Suzhou Wujiang District Power Supply Branch, and State Grid Zhejiang Jiashan County Power Supply Co., Ltd. jointly issued the "Yangtze River Delta Integrated Development Demonstration Zone Electricity Action White Paper (2020)" (hereinafter referred to as the "White Paper"), which is a further implementation of the Yangtze River Delta power integration.

It is understood that in July 2019, the central government clearly designated Wujiang, Suzhou, Jiashan, Jiaxing and Qingpu, Shanghai as the Yangtze River Delta Ecological Green Integrated Development Demonstration Zone (hereinafter referred to as the "Demonstration Zone"), and unveiled it in Shanghai on November 1, 2019. The white paper defines the "roadmap" for the demonstration zone's power integration action and lists a detailed "task book". In the future, power companies in Shanghai, Jiangsu and Zhejiang will jointly create an energy ecology of consultation, co-construction, co-management, sharing and win-win, and serve the energy transformation and upgrading of the demonstration zone.

Promote 110 kV cross-regional chain

It is understood that the power companies in the three places focus on the two key points of "integration" and "high quality", promote the safe, reliable and intelligent interconnection of the demonstration area's energy system, promote the green upgrade of regional energy production and consumption, and create a model for power companies to fully integrate into the integrated development of the Yangtze River Delta.

In fact, as early as May last year, State Grid Shanghai Electric Power, together with State Grid Jiangsu Electric Power and State Grid Zhejiang Electric Power, jointly launched the preliminary work of integrated power in the Yangtze River Delta and issued the "Yangtze River Delta Integrated Power Development Action Plan (2019)". After nearly a year of exploration, power companies in Shanghai, Jiangsu and Zhejiang have innovatively practiced the cross-provincial distribution network "mutual assistance, mutual protection, interconnection, mutual supply and mutual backup". At present, the Qingpu-Jiashan and Qingpu-Wujiang 10kV interconnection projects have been completed and connected, opening up the "dead end" of power, and realizing the power supply support of the Qingpu distribution network to Jiashan customers in the fight against Typhoon "Taba".

According to the white paper, the power companies in the three places will accelerate the coordinated planning of power grids, promote the research and construction of inter-provincial power grid interconnection, further optimize the grid structure, and carefully polish the "diamond-shaped" distribution network in Hongqiao Business District. "In the future, the power companies in the three places will pay attention to the construction progress and needs of key areas such as the Water Village Living Room, Xicen Science and Technology Innovation Center, Wujiang High-speed Railway Science and Technology Innovation City, and Sino-Singapore Jiashan Industrial Park, optimize the grid structure, and build an internationally leading urban distribution network." An insider told reporters that at the same time, research on the technical principles and operation and management models of inter-provincial (prefectural) distribution network interconnection and supply will be carried out, and the construction of distribution network liaison projects in the demonstration area will be expanded to create an integrated distribution network in the demonstration area with sufficient line liaison, flexible load transfer, and strong grid structure, so as to help build a world-class urban agglomeration in the Yangtze River Delta with high-quality development of the distribution network.

Ma Xiaoli, director of the Development Department of State Grid Shanghai Qingpu Power Supply Company, told reporters that at present, Xihongqiao has initially formed a "diamond-shaped" distribution network connection, with 10 10kV switch stations forming 4 double-ring networks and equipped with self-healing systems; in 2020, after the implementation of relevant projects, 13 10kV switch stations will be connected in series to the double-ring network, and a total of 8 double-ring networks will be formed; in the long term, all 45 or so switch stations in the power supply area of ​​the CIIE will form a "diamond-shaped" power grid with 13 double-ring networks.

"The demonstration area has a relatively strong power grid structure. The 110 kV power grids in the key areas of the three places have formed a double-sided power supply chain structure. However, the 110 kV power grids in the border areas have not yet formed a chain. Some 110 (35) kV substations are powered by the same 220 kV substation." Ma Xiaoli revealed that for this reason, the power companies in the three places will explore the cross-regional chaining of 110 kV substations that share 220 kV power points to form a highly reliable double-sided power supply chain connection. For example, the 110 kV Ludong substation in Wujiang Fenhu High-tech Zone and the 110 kV Shengdong substation in Shengze Town can explore the 110 kV cross-provincial chaining with the adjacent substations in Jiashan.

The regional power supply reliability rate is expected to reach "four nines"

Many interviewees believe that the integrated power construction in the Yangtze River Delta will enhance the power supply capabilities of the demonstration zone.

On December 1, 2019, the Central Committee of the Communist Party of China and the State Council issued the "Outline of the Regional Integrated Development Plan for the Yangtze River Delta" (hereinafter referred to as the "Yangtze River Delta Planning Outline"), which pointed out that it is necessary to accelerate the construction of regional power grids and improve regional power exchange and supply guarantee capabilities.

It is understood that after the East China UHV AC ring network was put into operation, the power exchange capacity, the ability to receive power from outside the region and the stability of the power grid in the Yangtze River Delta region were effectively improved. The Xiangjiaba-Shanghai, Jinping-Southern Jiangsu, Ningdong-Zhejiang, Northern Shanxi-Jiangsu, Ximeng-Taizhou, Zhundong-Southern Anhui and other UHV DC projects respectively transported hydropower in the southwest and thermal power, photovoltaic power and wind power in the northeast, north China and northwest to the Yangtze River Delta region, realizing the complementarity of water, fire, wind and light. In addition, the planned Baihetan-Jiangsu and Baihetan-Zhejiang UHV DC projects will also be located in the East China UHV ring network area, further improving the level of clean electricity in the Yangtze River Delta region.

Specifically in the demonstration area, there is still an unbalanced situation of low capacity-load ratio in some local areas and excess capacity in adjacent areas, especially in some border areas, the inter-station connection rate of 10 kV lines is low, and some lines have no connection or only the first section is connected, which affects the load transfer capacity and increases the number of customers during power outages. The regional power supply reliability needs to be further improved. In this regard, after the integration of power in the Yangtze River Delta, the role of the main grid hub will be more prominent, and the overall power supply reliability rate of the region may reach "four nines", and the power supply reliability rate of key areas is expected to reach "five nines".

The Outline of the Yangtze River Delta Plan also points out the need to promote the construction, transformation and intelligent application of power grids, optimize the construction of the Anhui power transmission to the east and the Three Gorges hydropower transmission channel along the river, and carry out key technology research on regional large-capacity flexible power transmission, regional smart energy networks, etc.

To this end, the power companies in the three places will promote the construction of 500 kV Wujiang South and 220 kV Fenhu, Xinze, Lvzhou and 110 kV Hongtang power transmission and transformation projects. "We will study and promote the unification of technical standards in the demonstration area, carry out technical transformation and equipment operation management mode upgrade work, build smart substations, realize fault prediction and rapid repair; establish a power dispatching sharing service platform to realize dispatching data intercommunication and efficient collaborative office." The above-mentioned person revealed that at the same time, the three places will innovate and practice cross-regional emergency rescue and disposal, fully integrate and utilize the emergency repair resources of the three places, and optimize the layout of emergency material storage and emergency rescue bases.

Create a first-class cross-regional business environment

In addition to improving power supply reliability, power companies in the three locations will continue to deepen the application of the integrated electricity service platform, focusing on improving service efficiency and customers' "access to electricity" levels.

The white paper requires that the power grids in the three places will form a seamless integrated service model, so that the total power connection time for low-voltage small and micro enterprises will not exceed 10 days, and the total power connection time for 10 kV business expansion will be reduced by 20%, further enhancing customers' "sense of gain" and achieving a world-class business environment. "The highest standards of China's power supply services were born here." An unnamed insider told reporters that power companies in Shanghai, Jiangsu and Zhejiang will establish an online and offline integrated service system, take the lead in building a website platform, customer mobile terminal, and business hall experience terminal covering the demonstration area, so that small and micro enterprise customers "don't have to run once."