A non-intrusive load decomposition algorithm for residents

In view of the large amount of data involved in the existing decomposition algorithm, which leads to low decomposition efficiency and high hardware requirements, a non-intrusive load decomposition method based on hidden Markov model (HMM) and improved Viterbi algorithm is proposed. First, the steady-state current data of the load is monitored and collected, and then the monitoring value is quantified and the probability distribution of the quantized monitoring value is created. Finally, the state of the load is identified from the probability distribution. According to the correlation of a composite state transition composed of states of multiple loads, the corresponding HMM model is created. Based on the matrix sparsity, the compression algorithm is used to reduce the amount of data stored. By using the query algorithm and the improved Viterbi algorithm, the calculation of zero probability items can be avoided, and the decomposition efficiency can be greatly improved. Results from simulation and real data have been used to verify the performance of the proposed algorithm.