The Theory And Practice Research Of GIS Intelligent Measurement System

With the development of power system, the demand on the reliability and the automatism of Gas Insulted Switchgear (GIS) is increasing. Especially, it is demanded that GIS should be automatic and intelligent entirely in measurement, control and protection to the greatest extent because of the implement of unattended substation automation system. At the same time, as the development of the microelectronics technology, power electronics technique, electrical technology, computer control technology and network communication technology, SMART GIS which takes the digital processing technique as the core appears. The paper establishes SMART-GIS intelligent measurement system in theory and practice research aspect systemically, which focuses on the current and voltage measurement, including sensor design, circuit project choice, model parameter analysis, error compensates method, etc., based on the analyses of SMART GIS's project on abroad.The integral and the periphery design of the system are solved. Firstly, the paper establishes the framework of GIS intelligent measurement system consisting of measurement item choice, measurement means, target system and circumstance by having researched the design task. The system adopts modularization design which comprises density monitoring and switch appliance monitoring. Furthermore, this paper discusses structure and model between electronic transducer and its standard interface, summarizes the design method of standard interface by analyzing IEC61850. Then in the electromagnetic compatible aspect, it also analyses the electromagnetic characteristic and transmit route in GIS and puts forward the restrain method in hardware and software.Rogowski coil is the current sensor. On the basis of theory, it analyses the electromagnetism disturb of contiguous GIS buses and brings forward the notice items of Rogowski coil design. By using ANSYS, it has done the simulate research of its electric field. Coaxial capacitance is the voltage sensor which makes full use of the axisymmetric feature of GIS's structure. The basic principles of coaxial capacitance are summarized which includes the equivalent circuit and the phasor diagram of coaxial capacitance, the analysis to static characteristic and transient characteristic, particularly short circuit on the primary and reclosing on a line with trapped charges. On the basis of theory, a prototype of coaxial capacitive voltage sensor for 220kV GIS is considered in the design of the voltage sensor such as the diameter; length and edge effect which are described in details. It is analyzed that the impacts of error factors and the compensating measures to improve the performance of the...