The Application Of Medium Voltage Low Power Electronic Transformer In Digital Substation

This thesis analyzes the limitations of digital technology applied in traditional substations. Then puts forward the definition and characteristics of digital substation by summarizing relevant research conclusion, and discusses the model and function of stratification of digital substation. Digital substation core technology, communication network construction and implementation are preliminarily studied. After that the thesis studies the components, principle and use of the status quo of electronic transformer. Focus on researching the principle, characteristics and advantages of low power electronic transformer, put forward the innovative practical solutions in view of the low power electronic transformer partial pressure problem. Finally, the thesis Originally designs specific applications in the low voltage network ,according to the characteristics of Shanghai power network.Digital substation Based on IEC61850 standard, refers to electrical equipments in substation realizing digital communication, digital primary equipment and the Secondary intelligent device modeling and communicating on total station unified platform, and Achieving interoperability between each other in this platform. In digital substations the equipments are divided into three layers logically -- substation level, bay level and process level, according to the two functions of monitoring and protection.Low power electronic current transducer is based on the traditional electromagnetic induction principle, with stable performance, wide measurement range and high precision, meeting the practical requirement of the engineering. Compared to the traditional electromagnetic transformer, protection and measurement can be achieved in a single transformer, which reducing transformer combination type, showing convenience to the power grid companies and manufacturers. And compared to the Rogowski air-core coil current transformer, integral circuit is no needed, primary and secondary voltage phases are the same, t the secondary load impedance requirement is low, and practicability is better and more flexible.Low-power electronic voltage transformer has simple structure, process maturity, product versatility, small volume and light weight, the use of flexible and strong adaptability, wide frequency response range and Non ferromagnetic resonance problems, its secondary side can be short-circuited, protection and measurement can be achieved in a single transformer.Low power electronic transformer is of products mature and flexible application, particularly suitable for use in low voltage network in combination with combined switch device. After problems in Practical engineering applications are well resolved, it will be more widely applied In the future power grid construction...