The DC back-to-back power grid project in the Guangdong-Hong Kong-Macao Greater Bay Area was put into operation

On May 25, the DC back-to-back power grid project in the Guangdong-Hong Kong-Macao Greater Bay Area was officially put into operation
.
The project applies the world's most advanced flexible DC technology to decompose the originally connected large power grid in the Guangdong-Hong Kong-Macao Greater Bay Area into multiple asynchronous small regional power grids, which can not only operate in different areas, but also support each other, which can not only prevent the "fire of the company" in the event of an accident, cause large-scale power outages in the power grid, but also absorb and utilize clean energy
such as wind and solar on a larger scale.

To grasp projects is to grasp development, and to seek projects is to seek the future
.
After the completion of the Guangdong-Hong Kong-Macao Greater Bay Area DC back-to-back power grid project, the Guangdong target grid project will fundamentally resolve the extreme situations that may occur such as excessive short-circuit current in Guangdong power grid, risk of multiple DC landing points, and large-scale power outages, and significantly improve the power supply and allocation capacity
of Guangdong power grid.
It is expected that in 2022, the power transmission from west to east will not be less than 188.
3 billion kilowatt hours, and the power exchange capacity of the east and west of Guangdong Province will be increased from 4.
1 million kilowatts to 10 million kilowatts
.

"This is a grid project
with an internationally leading level.
For the first time in the world, reasonable zoning and flexible interconnection of the complex structure of the power grid have been carried out, which has greatly improved the security and stability of
the power grid in the Guangdong-Hong Kong-Macao Greater Bay Area.
Rao Hong, academician of the Chinese Academy of Engineering and chief scientist of China Southern Power Grid Corporation, said
.

The "stabilizer" of grid security

Guangdong-Hong Kong-Macao Greater Bay Area will increase power supply capacity by 80%

The Guangdong-Hong Kong-Macao Greater Bay Area is the region with the highest concentration of electricity load in South China, with the Pearl River Delta region accounting for 77%
of the province's load.

Guangdong is developing offshore wind power on a large scale, promoting the concentrated continuous development and utilization of projects, and building a 10-million-kilowatt-level offshore wind power base in eastern and western Guangdong to support the rapid development of
renewable energy.
The extensive access of interactive energy facilities such as large-scale grid integration of new energy, distributed energy systems, electric vehicles, and energy storage will profoundly affect the operation
of the power system from all links of generation, transmission and distribution.
At the same time, the construction of flexible DC back-to-back projects connecting different regional power grids provides important support
for the safe and stable operation of Guangdong power grid.

The DC back-to-back power grid project in the Guangdong-Hong Kong-Macao Greater Bay Area is mainly divided into two parts: one is the Guangzhou project, which connects the northwest Zhuhai regional power grid and the northeast Zhuhai regional power grid; The second is the Dongguan Project, which connects the southwest Zhuhai regional power grid and the southeast Zhuhai regional power grid
.

After the completion of the project, within the Greater Bay Area, the originally connected large power grid will be decomposed into multiple unsynchronized small regional power grids, with "firewalls" between each other to avoid "fire and camp": a small area can be quickly isolated to control the power outage in a small area
.
Outside the Greater Bay Area, flexible DC back-to-back projects will be built between eastern Guangdong and western Guangdong to realize east-west interconnection in Guangdong, and then divide the power grid in the Greater Bay Area, eastern Guangdong and western Guangdong into three interconnected but not mutually affecting regional power grids
.

"It is to realize the independent networking of the AC power system through direct current, just like two people 'back to back' usually 'support each other', and 'let go at any time' when encountering faults that cannot be eliminated to avoid large-scale power
outages.
" Pang Peng, general manager of the infrastructure department of Guangdong Power Grid Corporation, said that it is estimated that after the series of projects marked by the DC back-to-back power grid project in the Guangdong-Hong Kong-Macao Greater Bay Area are put into operation, the power supply capacity of the Guangdong-Hong Kong-Macao Greater Bay Area will be increased by 80%.

The "arena" made in China

The localization ratio of IGBT devices has been greatly increased to 50%

The project has achieved a series of technological breakthroughs and innovations, and also applied a variety of new equipment
.

"The DC back-to-back power grid project in the Guangdong-Hong Kong-Macao Greater Bay Area involves nearly 200 upstream and downstream enterprises in the industry, and in the field of power grid equipment alone, the project construction will drive about 8 billion yuan
in the upstream and downstream supply chain.
" Wang Liuhuo, manager of the project management department of the infrastructure department of Guangdong Power Grid Corporation, introduced
.

It is worth mentioning that for the first time, the localization ratio of insulated-gate bipolar transistor (IGBT) devices in engineering applications has been greatly increased to 50%, which completely solves the problem
of IGBT import dependence in previous projects.
IGBT is the core device of energy conversion and transmission, and is known as the CPU
of power electronic devices.

The technical research team of China Southern Power Grid Corporation has developed a national flexible DC converter valve section for the first time in China, realizing the complete autonomy and control of the core components of flexible DC converter valve, including IGBT, capacitor, IG-BT driver board and secondary board chip, and achieved the first trial
in this project.

The successful development and innovative application of this product solves the "stuck neck" problem of key components and components of flexible DC converter valves dependent on imports, achieves a breakthrough of "0 to 1", promotes the independent and controllable leapfrog development of flexible DC technology, and improves the core competitiveness
of China's electrical equipment manufacturing industry.

A "testing ground" for green technology

Create an eco-friendly and intelligent converter station

Guangzhou project is located in Zengcheng District, Guangzhou, adjacent to residential areas, the design scheme of flexible direct transformer water cooling and indoor layout is adopted for the first time in the project construction, which reduces energy consumption and achieves a noise of less than 48.
5 dB
in the whole station.
"One flexible transformer is the size of three large trucks, and we have 12 running them, and the sound is only equivalent to the volume of a normal conversation between two people, which is comparable
to the sound of an air conditioner when it is turned on.
" Zhu Bo, project manager of Guangzhou Engineering, introduced that the main appearance of the engineering building was designed by Chen Xiong, the designer of Guangzhou Baiyun Airport, and was naturally integrated with the surrounding environment
.

The Dongguan project has achieved the world's largest flexible DC transmission transformer with "low loss and high energy efficiency"
.
It is understood that the capacity of a single flexible transformer in the whole project reaches 575 megavolt-amperes, and the load loss of Dongguan engineering equipment is less than 760 kilowatts, and the full load loss is 1.
55‰, reaching the first-class energy efficiency level
of equivalent capacity.
"The 12 transformers in the whole project can save 30 million kWh of electricity a year, which is equivalent to reducing 30,000 tons of carbon dioxide emissions per year, contributing to the realization of the 'dual carbon' goal
.
" Wu Ke, project manager of Dongguan Engineering, introduced
.

Compared with Guangzhou Engineering, Dongguan Engineering also has some innovations
in the method of noise reduction.
"In addition to adding sound barriers on the fence, we also installed sound insulation and noise reduction devices on all 12 flex transformers
.
" Wu Ke said
.

The DC back-to-back power grid project in the Guangdong-Hong Kong-Macao Greater Bay Area has also made some useful explorations
in digitalization.
During the infrastructure construction process, the first 3D scene intelligent O&M converter station throughout the whole life cycle in China was built, and the system will integrate key infrastructure data and real-time O&M data at the converter station to realize intelligent operation, intelligent inspection, intelligent safety, intelligent maintenance and other applications
of 3D space scenes.

This series of innovations will turn the DC back-to-back power grid project in the Guangdong-Hong Kong-Macao Greater Bay Area into an ecologically environmentally friendly and intelligent converter station
.