Parameter error identification method for multi-doubtful parameters of power grid

Parameter error affects the quality of state estimation and the application of other senior software in energy management system (EMS). When there are multiple bad data of remote measurement and parameter errors, it is important to ensure the effectiveness of state estimation. This paper proposes an effective and practical parameter error identification method for essential data of power grid. Firstly, percentage residuals of all measuring data are calculated to obtain the set of suspicious measuring points and further the set of suspicious branches. Then, correlation indices of suspicious branches are calculated and sorted to get a descending sequence. The suspicious parameter corresponding to a suspicious branch is adjusted based on the Newton downhill method. Case study on a simple 5-node network and a practical power grid shows that the method purposed can identify the network parameter error and the measuring data error simultaneously, thus improving the accuracy of state estimation on essential data of power grid operation.