From quantitative change to qualitative change: the development prospect of power system and integrated energy disciplines

On January 3, 2020, the "7th Electrical Engineering Young Scholars' Disciplinary Frontier Seminar" was held in Hefei. The conference was co-sponsored by the China Electrotechnical Society and the National Natural Science Foundation of China's Electrical Engineering Discipline, and hosted by Hefei University of Technology. At this conference, experts from relevant project teams shared the latest results of the discipline development plan that the National Natural Science Foundation of China is organizing and writing in the field of power systems and integrated energy, and had in-depth exchanges on discipline development.

The study pointed out that achieving energy transformation and building a new generation of clean, low-carbon, safe and efficient energy system is the core strategic goal of my country's energy revolution. Continuously increasing the proportion of non-fossil energy in primary energy consumption is the main way to achieve energy transformation. More than 90% of non-fossil energy must be converted into electricity, and increasing the proportion of non-fossil energy in electricity is the main support for achieving energy transformation.

In this context, the form and characteristics of the power system are undergoing a process of qualitative change from quantitative change. The main trends in the development of the power system are the increasing proportion of renewable energy, the increasing proportion of power electronic devices, the continuous integration of information and physics, the increasing proportion of terminal power consumption, and the development from integrated energy to energy Internet.

The study believes that the priority development areas of the power system are the evolution and challenges of the power system, smart grid research, and transformative and disruptive technologies. The future power system faces many challenges in planning, operation, new transmission and distribution, and power market. In order to meet the challenges and achieve energy transformation, major countries in the world have taken smart grids as an important entry point and formulated national strategies in order to gain an advantageous position in the new round of energy revolution and the world's competitive landscape.

Smart grid is a new generation of power system built on the basis of high-speed two-way communication network, integrating new energy, new materials, new equipment and advanced sensing technology, information technology, control technology, energy storage technology, etc. It can better realize the reliable, safe, economical and efficient operation of the power grid.

China has established key projects on smart grids in the 973 and 863 programs of the 12th Five-Year Plan and the 13th Five-Year Plan. The National Natural Science Foundation of China has established a joint fund for smart grids and is planning to establish a major project on smart grids by 2030.

The study divides the development strategy of the power system into three stages: short-term, medium-term and long-term. The short-term (2021-2025) goal is to accumulate major smart grid technologies and equipment in the quantitative change process; the medium-term (2026-2035) is to achieve qualitative change and safe and efficient operation of the power system dominated by renewable energy; the long-term (2036-2050) is to achieve a 100% renewable energy power system (zero-carbon power system) and explore the energy Internet.

The research topics of the discipline's strategic planning are: power system planning; power system control and protection (transient); power system operation, dispatching and demand-side response (steady state); power market (energy trading mechanism); integrated energy system (microgrid, VPP, energy Internet, electrified transportation); new power transmission and distribution technology (UHV, DC grid, active distribution network); power storage and conversion; new smart grid technologies (cloud, big data, Internet of Things, mobile Internet, intelligence chain, cyber-physical system).

The study concludes by emphasizing that the power systems discipline will continue to evolve and become increasingly important.

Building a new generation of clean, low-carbon, safe and efficient energy system and achieving energy transformation is a major national need and a world technological frontier;

Vigorously developing and utilizing renewable energy sources such as wind and light is the main path to achieving energy transformation;

Renewable energy can only be used on a large scale if it is converted into electrical energy. The power system will become the core platform of the new generation of energy systems.

The installed capacity and electricity share of renewable energy are the core indicators for achieving energy transformation;

As the proportion increases, the form and characteristics of the power system will gradually evolve from quantitative change to qualitative change;

The scientific mechanisms, theoretical methods, engineering technologies and even knowledge systems of the power system discipline will also undergo a qualitative change from quantitative change, and textbooks will be rewritten.