Power System State Estimation: Practical Considerations

The current Power System State Estimator algorithm being used at Wisconsin Electric was installed in the summer of 1975. The purpose of this program was to constantly monitor system steady state security and provide system data where metering was unavailable. The solution method is a full gain matrix least-squares fit algorithm which provides line flows, voltage magnitudes and phase angles to system operators and security software modules. The purpose of this paper will be to discuss the implementation of this algorithm and the benefits and problems associated with it.