Design Of Traveling Wave Ranging Card In Power Network Fault Wave Recorder Based On Boundary Scan Technology

This paper mainly presents the design and realization traveling wave ranging card of fault wave recorder based on boundary scan technology.Traveling wave ranging card, which is the signal acquisition module of fault wave recorder, can parallelly sample 16-channel signal at a rate of 650ksps when some fault occurs in the power network, providing a scientific basis for fault analysis and fault location of power lines. When boundary scan technology is applied to the card, we can properly solve the complex problems of connectivity tests for it.The paper first introduces the technology in the development of testing circuit boards, the components of fault wave recorder and the principle of fault ranging. On this basis, we analyse the functional requirements of the traveling raging card, and design the card with the ADC of serial AD, the core of DSP and FPGA, the supplementary of SDRAM memory and other function modules. According to the chip packaging and the density of circuit connectivity, we give the circuits to be tested.Combining boundary scan structure, test methods and boundary scan description language and other technical standards, the paper presents the boundary scan test system based on PC's parallel port, analyses the structure and function of the test system, and gives a method on how to design a testable cuicuit. Finally, the paper presents parallel port driver and the design of the main moule of the test software.The traveling wave ranging card discussed in the paper has been finished, and the design for testability has also been completed. Software test for the circuit yields good results.