Power management algorithms necessary for voltage and frequency regulations and coordination logic among power converters are currently hot research topics, being fundamental for AC grid stability. However, inner controllers driving voltages and currents are essential for safe and reliable interfaces between AC and DC systems, since they actuate effective P, Q trackings. Indeed, converters may suffer from stability issues even at unit level, being them inherently nonlinear switching devices and connected to power grids with time-varying configurations. Due to deep penetration of power electronics, renewable sources and storage systems interfaced into AC grids, converters need often to work bidirectionally, further increasing challenges for stability. Thus, this paper shows robust control syntheses for voltage and current loops, trying to bridge the gaps and clarify open points left by the existing literature, as well as comparing the behaviors of tuned control schemes.
Toscani et al. (2025) studied this question.