A Port-Hamiltonian Control Framework to Render a Power Electronic System Passive

In this article, a control framework is proposed to render a power electronic system passive by adopting the port-Hamiltonian (pH) systems theory. The system has a power electronic converter, either grid-tied or islanded. The control framework consists of a lossless interconnection block and three control channels. It makes the power converter behave as a virtual synchronous machine (VSM). The three channels are designed to, respectively, generate the frequency and the flux of the VSM and a third quantity that is necessary for forming the lossless interconnection. It is proven that the closed-loop system is passive without the need of assuming constant frequency, constant voltage, and/or constant loads. It is sufficient to only assume that the load can be described as a passive pH model. Hence, the proposed control framework is very generic.