I. What is a smart substation?
Substations that automatically complete basic functions such as information collection, measurement, control, protection, metering, and detection, while also possessing advanced functions such as supporting real-time automatic control, intelligent regulation, online analysis and decision-making, and collaborative interaction of the power grid.
A smart substation mainly consists of two parts: intelligent high-voltage equipment and a unified information platform. Intelligent high-voltage equipment primarily includes intelligent transformers, intelligent high-voltage switchgear, and electronic instrument transformers. The intelligent transformer is connected to the control system via optical fiber, allowing for timely monitoring of transformer status parameters and operating data. When the operating mode changes, the equipment determines whether to adjust the tap changer based on the system's voltage and power conditions; when equipment malfunctions, it issues warnings and provides status parameters, thus reducing operating and management costs, minimizing potential risks, and improving transformer reliability to some extent. Intelligent high-voltage switchgear is high-performance switching and control equipment, equipped with electronic devices, sensors, and actuators, and possesses monitoring and diagnostic functions. Electronic instrument transformers, such as pure fiber optic transformers and magneto-optical glass transformers, effectively overcome the shortcomings of traditional electromagnetic transformers. The unified information platform for the substation has two functions: first, horizontal information sharing, mainly manifested in the unified information acquisition by various upper-level applications within the management system; and second, vertical information standardization, mainly manifested in the transparency of each layer's support for its upper-level applications.
Intelligent means human-centered, which means making the substation like a human adjusting it. When the low-voltage load increases, the substation sends out enough electricity to meet the increased load. When the low-voltage load decreases, the substation sends out less electricity to ensure energy conservation.
II. Technologies Related to Intelligent Substations
Smart substations are the physical foundation of smart grids, and their core technologies are intelligent primary equipment and networked secondary equipment. Research on technologies related to smart substations should include the following aspects.
(1) Intelligent substation technology system and related standards and specifications: study the architecture and technology system of intelligent substation, clarify the definition and positioning of intelligent substation, formulate corresponding standards and specifications, guide the construction and operation of intelligent substation in the future, and improve the standardization, openness and interoperability of intelligent substation.
(2) Dynamic Data Processing of Smart Substations: By developing an open smart substation system and improving communication equipment to achieve faster data acquisition rates, or by storing online measurement data in a local smart substation and then exchanging relevant data between various smart substations, treating each smart substation as an agent, a fully digital real-time decision-making application based on MulTI-Agent can be realized. On the advanced dispatch center side, a wide-area, panoramic, distributed, integrated EMS/WAMS technical support system needs to be developed.
(3) Automatic reconfiguration technology for intelligent substation systems and equipment: Establish a model self-description specification for intelligent devices to realize automatic modeling and model reconfiguration of systems and equipment in intelligent substations. During system expansion, upgrade and transformation, realize intelligent and rapid system deployment, testing, verification and error correction, improve the security of intelligent substation automation system and reduce system construction and debugging cycle.
(4) Intelligent substation distributed coordination/adaptive control technology: Develop distributed coordination/adaptive control technology and methods to solve the adaptive modification of relay protection, stability compensation and reactive power compensation device settings caused by flexible partitioning, and realize distributed intelligent control of microgrids and substations including power generation after disconnection.
