An Injected Impedance Measurement Based on Noninjected a Priori Results

In recent years, the deepening of China’s energy system reform has led to an increasingly severe problem of harmonic pollution, exacerbated by the integration of highpenetration power electronic devices and nonlinear loads. To tackle this challenge, this research proposes a novel dual-channel impedance measurement method that incorporates mutual correction. The methodology involves a two-stage measurement process. Initially, a non-injected method is employed to obtain a preliminary estimate of the harmonic impedance on the system side. Subsequently, an injection method is applied for precise measurement and mutual correction of specific harmonics. Simulation results validate the effectiveness of the proposed method in enhancing the accuracy of impedance measurements.