Improvements on “A new framework of consensus protocol design for complex multi-agent systems”

In the aforementioned paper Li et al. (2010) [6], a novel framework for consensus protocol design is developed, which can handle both homogeneous and heterogeneous subsystems in the frequency domain. In this article, the original problem setup is reformulated in the framework of decentralized stabilization for multi-input–multi-output (MIMO) system. It can be shown that the consensus protocol designs in Li et al. (2010) [6] are insufficient to guarantee the overall system stability. Then, a sufficient stability condition is presented. As an example, a PI controller is adopted to stabilize the overall system. The sufficient stability region of the PI controller is explicitly calculated for each subsystem. In addition, a consensus protocol is proposed by incorporating the internal model principle, which enables the multi-agent systems (MASs) to track general elementary signals.