Abstract Hydraulic impedance, as an efficient frequency-domain analysis alternative, has been widely utilized in hydraulic transient for decades. Since the mathematical expressions of systems with complicated pipe networks are usually rather complex, it is difficult traditional continuous impedance method to obtain analytical solutions system’s frequency responses directly. Therefore, equivalen...

This letter presents two frequency-domain modal analysis methods, “peak-picking” and “circle fit” used for current control interactions of grid-connected voltage-source converters (VSCs). Differing from the conventional resonance mode analysis, impedances are analyzed with their Nyquist plots, instead magnitude-frequency response, which leads to an accurate prediction on damping behavior system...