RMS-energy filter design for real-time oscillation detection

Real-time monitoring of power-system oscillations is a concern in the operation and control of synchronous power systems. A simple and powerful approach is to use an RMS energy filter. As defined in this paper, an RMS energy filter estimates the total RMS energy of a signal in a defined frequency band. This approach has been implemented in the operation control center at the Bonneville Power Administration for the past year, and it is being implemented in a DC modulation damping control monitoring system. This paper describes RMS energy filter design requirements, approaches, and alternatives. Simulation examples demonstrate the performance.