Research on a Broadband Impedance Measurement Unit with Multiple Perturbation Output Modes

In power distribution networks, the penetration rate of power electronic devices has been increasing by year, leading to problems like prominent issues of stability and harmonic over-limit. As a crucial important parameter for stability analysis and harmonic responsibility attribution, accurate acquisition of system impedance becomes particularly important. Existing impedance measurement unit generally can only inject a single type of perturbation signal for impedance measurement, making it difficult to meet the perturbation output requirements in different measurement scenarios. To address this problem, this paper designs a reconfigurable distribution network impedance measurement unit with multiple perturbation output modes, which can select appropriate perturbation signal type according to different measurement requirements, thereby significantly improving impedance measurement efficiency. Furthermore, corresponding control strategies and filter configurations are specifically designed to match different perturbation output signal types. Finally, MATLAB/SIMULINK simulations validate the effectiveness of the proposed impedance measurement unit with multiple perturbation output modes topology and control strategies.