Design Of Data Acquisition Station For New Type Generator-Transformer Unit Fault Recording

Large scale Generator-Transformer Unit (GTU) has been widely used in modern power system. Once fault happens, serious damage will be done. Fault recorders provide direct basis to analyze the origin and character of faults, and study countermeasures for anti-accidents. Therefore, it is especially necessary to study fault recording for GTU presently.Firstly, the thesis introduces the framework and working flow of fault recorders for GTU. It analyzes some defects exiting in current recorders such as few channels, low sampling rate, low speed of data transmission, poor compatibility of software in collection point and so on, according to DL/T 873-2004 Specification of Microprocessor-based Generator-Transformer Unit Dynamic Recorder. Finally, a new Data Acquisition Station (DAS) design is presented for fault recording.The concentrated architecture is adopted in the new DAS to replace modularization. Its analog channels are sampled under the control of DSP and CPLD. Sampled data with precise GPS time tag is transmitted through PCI bus. DAS software accomplishes fault algorithm, system memory management, and CPU mode transition from real to protected mode. Fault date is sent to Analysis Station (ANS) via network.At last, process and experience of system debugging are summarized and a series of tests are implemented to evaluate the DAS performance. Test results reveal that the design is in conformity with new power system specification, with high sampling rate and large data transmission capability, and helpful to improve the whole performance of GTU fault recorders.