An experimental study for the real scale impulse measurement setup of overhead distribution lines

In good conditioned laboratory, measurement of impulse voltage and current was not so complicate. But in field or real scale outdoor demonstrated overhead lines, it is not so easy, because induced high voltage shock to ground connection of instrument, distributed measuring device like HV divider and others. Also control of impulse current generator is one of the problems to get like a standard waveform. Most of all, the hardest problem is economical limitation. To get a economical measuring system, in the middle of concrete pole near to bottom but separate from ground plane, a measuring system combined with normal digital oscilloscope and ups with backup battery were installed using double shielded metallic box. And HV dividers and Rogowski coils installed and connected to oscilloscope through a hole of double shield box. And three measuring points were connected with normal control cable for connection of serial communication system. Communication structure were combined several RS485 modules and main desktop computer. To avoid HV shock from impulse current, simple switching circuit was assembled with control relays. With simple communication program and manual synchronized switching action, the measuring system was well done but data transfer speed was limited at 9600. The advantage of this measuring system is economic aspect and can be operated only 1 person minimum. This system was make good result in field condition with real scale demonstration system.