Distribution System Monitoring for Smart Power Grids with Distributed Generation Using Artificial Neural Networks

The increasing number of distributed generators connected to the distribution system at the low and medium voltage level requires a reliable monitoring of distribution grids. Economic considerations prevent a full observation of distribution grids with direct measurements. First state-of-the-art approaches using artificial neural networks (ANN) for monitoring distribution grids with a limited amount of measurements exist. These approaches, however, have strong limitations. We develop a new solution for distribution system monitoring overcoming these limitations by 1. presenting a novel training procedure for the ANN, enabling its use in distribution grids with a high amount of distributed generation and a very limited amount of measurements, far less than is traditionally required by the state-of-the-art Weighted Least Squares (WLS) state estimation (SE), 2. using mutliple hidden layers in the ANN, increasing the estimation accuracy, 3. including switch statuses as inputs to the ANN, eliminating the need for individual ANN for each switching state, 4. estimating line current magnitudes additionally to voltage magnitudes. Simulations performed with an elaborate evaluation approach on a real and a benchmark grid demonstrate that the proposed ANN scheme clearly outperforms state-of-the-art ANN schemes and WLS SE under normal operating conditions and different situations such as gross measurement errors.