Three Phase Power Detection

Project Team:

Chris Cundy

Tim Locke

Braden Olson

Faculty Advisor:

Dr. Nehrir

EE492 Senior Design Project Montana State University

Abstract:  The power line phase matching system is being developed to correctly and quickly identify the phase of a three phase power system.  It will aid workers during new installs and rebuilds of existing power service.  It can also be useful in load balancing on each phase.  The basic goal of the project is to detect and compute the phase of a line relative to a reference.  The reference will be at the substation for a given area and a utility worker will have a portable device to detect the phase of a certain line. 

The project is broken down into four parts:

1. Two computers must have their system clocks synchronized.  This is to allow a time reference for the phase computations that will follow.  Millisecond accuracy is needed in the synchronization so Network Time Protocol software with GPS clock reference will be necessary.

2.   Data acquisition will be accomplished with a USB A/D made by Measurement Computing.  A sample rate of 10kHz will be used.  Each DAQ will be running with the two synchronized computers.  Once a common start time is set the two DAQ�s can sample the voltage of the lines with enough accuracy to perform phase calculations.

Measurement Computing 1208-FS

3.         Communication from the PC in the field and the PC at the substation is necessary.  This can be accomplished by using cell phone technology.  Using a simple internet connection provided by a cell phone, the transmission of the data files from the DAQ is possible.

4.         Now that one PC has the sample information from both the field PC and the substation PC it is possible to perform the proper algorithm to find the phase difference of the two lines.  This will be done using MATLAB.