Microperturbation Method for Power System Online Model Identification

The microperturbation method (MPM) is an advanced online model identification technique for power systems, which utilizes some specifically designed multisine signal to perturb the system and to consequently stimulate amplitude-limited probing response that has desirable signal-to-noise ratio (SNR). The MPM removes the ambient noise from the contaminated probing response using statistical signal processing techniques and identifies system models by orthogonal decomposition-based subspace identification method (ORT). The capability to identify the precise system model at a low cost without impacting the system security gains the MPM tremendous application potentials. In this paper, we present an overview of the MPM, as well as its critical techniques and implementation procedures, and also shed lights on its potentials in real-time online applications in the power industry. The proposed approach is validated in an actual power system where the system dynamic model is successfully identified.