On-Line Current Instrumentation Channel Error Correction Within Merging Units Using Constraint WLS Dynamic State Estimation Method

This paper presents an on-line current instrumentation channel error correction method. The physically-based high fidelity model of entire current instrumentation channel is developed, which consists of the current transformer (CT), the instrumentation cable, and the burden resistor. The constraint dynamic state estimation (DSE) is constructed to estimate the CT primary current, which can be directly reported in merging units (MU) as sample by sample outputs. Extensive test cases demonstrate that the proposed algorithm can accurately reconstruct the CT primary current in different saturation scenarios.