Testing and Evaluation of Smart Substations

Smart substations (including power plant step-up substations and AGC) are an important foundation and support for smart grids. Smart substation equipment has key technical characteristics such as information digitization, functional integration, compact structure, and status visualization. The smart substation system should establish a unified information platform for panoramic data within the station, allowing for standardized and regulated access to data by various subsystems and standardized interaction with other systems such as smart grid dispatching.
The construction of smart substations should be standardized to ensure they meet the requirements of industrial applications, such as easy expansion, upgrading, modification, and maintenance. The communication network and system of smart substations should be built based on the DL/T 860 standard. A standardized information model should be established, including various data such as real-time grid synchronization information, protection information, equipment status, and power quality, to meet the requirements of data integrity and consistency of the communication network and system.
Intelligent substations should be able to easily connect to new energy sources, monitor and manage the operating status of secondary equipment, and support the safe, stable, and economical operation of power grids at all levels.
Intelligent substations should meet the requirements for information acquisition and measurement functions, control functions, status monitoring functions, protection functions, metering functions, communication functions, system functions, performance requirements, and auxiliary facility functions.
Intelligent substations should realize a unified world, unified data, synchronized data profiles, plug-and-play functionality, intelligent distribution, centralized management, interconnectedness, and a safe and reliable automated system.
Intelligentization is a transformation, and transformation requires design and research. The results of this design and research are verified through experimentation to ensure their conformity with the design and research objectives. The effectiveness, reliability, applicability, and economy of the experimental results are evaluated. After optimization and improvement, industrial production commences. Product quality is inspected before engineering application, and the completeness of the product design, the production process, and the integrity and consistency of quality control are evaluated through product quality inspection of the production results. To ensure the construction of intelligent substations meets the requirements, an evaluation and inspection platform must be established to study the needs and implementation pathways of intelligentization, research testing methods and tools, and the scope of evaluation. This will serve to promote the application of intelligent substations. The effectiveness of research results is assessed through experimentation, the degree of completion is evaluated, and the feasibility of implementation and promotion is assessed.
The evaluation and testing of intelligent devices and components, compared to previous testing activities, simply adds the requirement for intelligence and increases the types of equipment. It still involves commissioned testing to assess the conformity of the designed prototype with the design objectives, preparing for trial production. It still uses type testing to verify the quality level of the trial production prototype, preparing for mass production. It still uses sampling inspection to evaluate the product quality level, preparing for widespread application. To ensure the smooth development of intelligent substations, the guidelines for intelligent substations require that intelligent devices and components undergo periodic sampling inspections before being promoted and applied in intelligent substations. In other words, the performance indicators of equipment or components after intelligent design cannot be lower than the requirements of relevant standards and applications. Because the information processing method of individual devices has changed, both hardware and software have been redesigned. Certification of the performance indicators of new equipment and sampling inspections are necessary before widespread application.
The evaluation and testing of intelligent substation automation systems differs from previous testing activities only in that it incorporates the added requirements of intelligence and changes in system structure. These structural changes alter data flow, introducing uncertainties due to insufficient application maturity. Therefore, testing is necessary to verify and evaluate the design and research. Testing must ensure the system's performance indicators meet or exceed relevant standards and application requirements. Testing should be conducted in typical operating system environments to verify system functionality and performance, guaranteeing application quality and standards before engineering application.
To meet the needs of smart substation development, a platform (simulation system) for testing, evaluation, and verification needs to be built. This platform would implement a smart device or component (bay layer, process layer), and test the system's functionality and performance after integration. A smart substation backend (station control layer) would also be implemented, and its functionality and performance would be tested within the simulation system. The Telemetry and Substation Automation Research Laboratory of the China Electric Power Research Institute, commissioned by the State Grid Corporation of China, is currently building such a simulation system, which is expected to be operational within the year.
The construction of smart substations requires addressing the methods and testing equipment for value transfer and traceability, the testing methods and equipment for merged units (MUs), intelligent devices and components, and intelligent systems and remote control equipment. These testing devices and tools should be adaptable to flexible configuration, functional sharing, modeling, and standardization, enabling qualitative and quantitative reproduction of the operating environment. Only then can simulation testing of smart substation research results be conducted, serving as an evaluation and verification platform for research findings, and as a research platform for smart substation scientific research.
The construction and development of smart substations is progressing rapidly, and current evaluation and testing cannot keep up with the needs of this development. Currently, transmission protocol conformance testing includes client-side and server-side testing of remote control equipment, measurement and control units, merging units, electronic instrument transformers, protection devices, signaling substations, fault recording devices, fault recording systems, power systems, environmental monitoring systems, online switch monitoring, online transformer monitoring, online temperature monitoring, online motor monitoring, switches, and testing equipment. Engineering application testing is also underway, but qualitative and quantitative testing is not yet complete, introducing some uncertainties to its widespread application. Through everyone's joint efforts, strengthening evaluation and inspection work, and improving supervision and services for smart substation construction, the construction of smart substations will surely achieve better development.