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Precursor-derived silicoboron carbonitride ceramic (PDC-SiBCN) has attracted significant attention as an advanced electromagnetic (EM) wave-absorbing material. However, the inherent porous and brittle characteristics limit its application as a structural load component in an EM interference environment. In this study, phase-transformation HfO2 nanoparticles were incorporated into PDC-SiBCN to reduce volume shrinkage, improve bonding interactions, and control structural defects, simultaneously boosting the plastic deformation and EM performance of brittle ceramics. The obtained HfO2/SiBCN ceramic showed enhanced flexural strength of up to 430.1% compared with that of the pure SiBCN ceramic. Furthermore, the HfO2/SiBCN ceramic also demonstrated excellent high-temperature EM absorption. The minimum reflection coefficient (RCmin) could reach −45.26 dB, and the effective absorption bandwidth (EAB) covered 2.80 GHz of the X band at 2.28 mm thickness at room temperature. Furthermore, the RCmin can still reach −44.83 dB, and the EAB can cover 2.4 GHz at 1.58 mm even at 1073 K. This work shows that phase-transformation nanoparticles could simultaneously improve the deformation ability and EM wave absorption properties of SiBCN ceramics. The results could guide the design and preparation of PDCs with strong carrying capacity and excellent EM absorption, even in harsh environments.

In this paper, a small signal model based on droop controller is established for the self-synchronous voltage source parallel system. The influence of droop coefficient on system stability is analysed, and the constraint conditions of droop coefficient are given. Based on the analysis of the parallel system of self-synchronous voltage source inverter, a multi-machines parallel control scheme of self-synchronous voltage source inverter is formulated. The model and test platform are built to carry out the parallel simulation and experimental verification of distributed line impedance parameters. Simulation and experimental results show that the proposed control strategy can achieve good dynamic and steady-state power sharing.