Cai Taoyuan: After the goal of building a new type of power system was put forward, leading enterprises and experts in the industry made exploratory interpretations one after another, and its connotation has been constantly improved. According to the current research progress, green and efficient, flexible and open, widely interconnected, safe and controllable are the main characteristics of the new power system, which represents the evolution of the power grid to a highly digital, clean and intelligent direction.

Power equipment is an important part of power system. The R&D layout of power transmission and transformation enterprises should fully consider the requirements of new power system construction in order to adapt to the development of power grid. At the same time, the general thought and layout of power transmission and transformation enterprises must also change according to user requirements.

In the past, power transmission and transformation enterprises generally centred their layout on component manufacturing, and manufacturers such as high-voltage switches, transformers and power electronics paid more attention to the reliability of components and lacked attention to the overall demand and safety of the power grid. Therefore, the green and low-carbon characteristics of the new power system require transmission and transformation enterprises to consider the carbon emissions of the whole life cycle of the equipment; the safety and controllable goal of the new power system requires transmission and transformation enterprises to pay attention to the equipment with faster response speed and predict its performance in advance.

Cai Taoyuan:According to the "14th Five-Year Plan" for science and technology innovation in the energy field, in combination with the requirements of new power system and technological development at home and abroad, we will deeply participate in the Innovation Technology Alliance for New Power System(hereinafter referred to as the "Alliance") while adhering to the iterative upgrading of conventional products. We will take the technical key projects proposed by the Alliance as the carrier, combine the company's early technical advantages in DC distribution network and user side energy storage, and coordinate with various special plans to further develop the market demand of new power system distribution network.

For example, nuclear power, as a conventional inertia power source, is of great significance to stabilizing the quality of the power grid and supporting the realization of the "carbon peaking and carbon neutrality" goal. Among them, the localization of nuclear safety grade switching electrical equipment and core components is the focus of our research and development. We are continuously increasing investment in R&D to contribute to realizing the localization of nuclear power equipment and constructing a stable new power grid. At the same time, relying on our engineering advantages and practical experience in technology research and development, scenario application and subject research, we actively participate in the formulation of relevant standards and provide cases and experience for the construction of key technical standards.

In the future, the new power system will present a trend of deep integration of digital and physical systems, deep collaboration and interaction among various links and multi-elements of Source-Grid-Load-Storage. Power transmission and transformation enterprises will carry out research in green manufacturing, equipment environmental protection, equipment status perception and digitization, and continuously create information-based, intensive and green products and services to create value for users. At the same time, power transmission and transformation enterprises should take the overall planning of energy, science and technology as the key link, coordinate with special research topics, continuously improve their understanding of the characteristics and operation mechanism of new power systems, and do a good job in the upstream and downstream joint work of industrial chain and innovation chain, promote technological development and industrial upgrading, and realize comprehensive docking with new power systems.

Cai Taoyuan:The high-proportion new energy power system presents two main characteristics changes: on the one hand, the new energy power generation has characteristics of intermittency and uncertainty ; on the other hand, the grid-connected control characteristics of new energy are greatly different from those of conventional power supply, requiring a large number of power electronic devices to be continuously connected, which makes the operation characteristics of the power grid change. Intermittency and uncertainty of power generation, as well as the gradual electrification of power, are new challenges for the safe operation of power grid.

To realize stable operation of power grid, the key is to depend on the performance improvement of various power transmission and transformation equipment and the application of innovative technology. Therefore, it is a common task and challenge for the power transmission and transformation industry to quickly adapt to the new technical requirements proposed by the power grid changes and change the previous working ideas of passively meeting the requirements of the power grid.

Power transmission and transformation enterprises should grasp the rare development opportunity, follow the national strategic orientation, and constantly explore and practice in technology research and development, talent introduction, management mode, production organization, etc. At the same time, they need to strengthen the technical accumulation in the direction of power electronics, persevere and practice internal skills and take steps towards the power electronics transformation bravely on the basis of traditional equipment technology.

In terms of power electronic equipment, our current industrial layout is mainly concentrated in the fields of power quality management, energy storage, DC, etc. In the face of the requirements of new power system construction, we will focus on friendly grid-connection technology and transform grid-connection equipment from "Grid-following" to "Grid-forming". Energy storage is an important role in the future power system, so it is necessary to focus on the next generation of safe, efficient and green energy storage, which plays a role in various fields of Source-Grid-Load-Storage. In terms of DC,
DC distribution network is the research focus, including converter valves, power electronic transformers, circuit breakers, load balancing, etc., aiming at establishing a comprehensive "DC ecology." In addition, Taikai Group is actively carrying out intelligent and digital transformation research, integrating equipment and services into the information network to provide users with all-round services.

Cai Taoyuan:Large-scale access of new energy will lead to the increased risk of frequency exceeding limit, prominent system voltage stability problems, serious transient overvoltage in high-proportion areas, complex power angle stability characteristics, frequent broadband oscillation phenomenon and other problems. Therefore, the stability, flexibility and controllability of new power system will be the basic requirements.

Among them, flexible and controllable are based on the state perception of power grid system. Traditional equipment needs intelligent upgrading, and intelligent control is finally realized by using all-round digital technology such as equipment state perception, coupled with analysis and judgement such as edge calculation. This requires power transmission and transformation enterprises to carry out a full series of digital transformation, realize all-round digital upgrading from design, manufacturing, operation and maintenance, establish digital factories, and meet the flexible requirements of power system.

Specifically speaking, in terms of products, it is necessary to digitally upgrade traditional power equipment, implant sensors and intelligent monitoring units into traditional high-voltage power transmission and transformation equipment, develop fast switches with shorter opening time, stepless voltage regulation multifunctional flexible transformers, and cooperate with SVG (static var generator) and other equipment to realize flexibility of AC power transmission and transformation system. We will step up the development of flexible DC power transmission and distribution equipment, including DC circuit breakers, DC transformers, converter valves, power routers, etc., to build AC-DC hybrid flexible interconnected transmission and distribution system.

Cai Taoyuan:According to the Alliance's major technology joint innovation framework, 33 of them are related to electric power equipment manufacturing, which are the directions we need to focus on and lay out. Among them, in the field of power generation, it is necessary to study key technologies such as new energy DC convergence and direct-hanging energy storage support. At present, the new direct-hanging energy storage equipment has been safely operated in Zhuhai Triangle Island offshore wind power storage project. In the field of power transmission and transformation,we have studied high-voltage and large-capacity DC breaking technology and domestic power semiconductor device replacement technology. The 500kV DC circuit breaker developed by us has been applied to Zhangbei Flexible DC Transmission Demonstration Project. In the field of power distribution, we have studied key technologies such as DC transformation, high-efficiency power conversion and medium voltage flexible interconnection. The multi-port power router equipment developed by us has been applied to Dongguan Data Center Demonstration Project of National Key R&D Plan, and the three-port DC fault current control system has been applied to Zhuhai Tangjiawan Medium-Voltage Flexible Power Distribution Demonstration Project.

Relevant intelligent, digital,primary and secondary integration and other equipment will develop iteratively with the construction of new power system, and energy system digital technology will digitally empower new power system and assist in the construction of smart grid. At the same time, the improvement of power electrification level makes protection, secondary system, dispatching and other links change greatly compared with traditional power grid, especially large-scale new energy grid connection and AC/DC hybrid increase the complexity and uncertainty of power system. In this regard, relying on advanced online simulation platform, we will cooperate with China Electric Power Research Institute and provincial electric power research institutes and universities to carry out research on new power system simulation technology and explore equipment and system solutions.