Polyether‐based polyurethane/poly (methyl methacrylate‐co‐ethyleneglycol dimethacrylate) interpenetrating polymer networks [PU/P (MMA–co–EGDMA)‐IPNs] were synthesized and used as adhesives to adhere vulcanized natural rubber (NR) and soft polyvinyl chloride (PVC). The structure and morphology of the IPN adhesives in bulk and near the adhesive/substrate interfaces were investigated. A new mechanism of adhesion called conjugate interpenetration of networks across interfaces, which is suitable for IPN adhesives and polymer substrates, was put forward. According to this mechanism, while forming simultaneous interpenetrating networks in the adhesive, the monomers in the IPN adhesive can permeate polymer substrates and polymerize in situ to form gradient IPNs, thereby producing conjugate three‐component IPNs near the adhesive/substrate interfaces. It is the conjugate interpenetration of the networks across the interfaces that strengthens interfacial combination remarkably and results in high bond strength of IPN adhesives. © 1994 John Wiley & Sons, Inc.

Commutation failure (CF) is one of the common faults in HVDC system, a new issue arising in multi-infeed HVDC systems is whether all the inverters will suffer from commutation failures concurrently, and the interaction between AC and DC systems is much more complicated. According to the mechanism of commutation failure, influencing factors and judgment basis, this paper proposed a commutation failure detection method based on the critical multi-infeed interaction factor (CMIIF). A three-infeed HVDC system was modeled in PSACD/EMTDC, The simulation results of the test system and an actual system proved the accuracy and validity of the proposed method.

Bearingless motorized spindle is a kind of spindle structure that combines a bearingless motor with a motorized spindle. It has the advantages of a motorized spindle and a bearingless motor, which can further improve the speed of the machine tool spindle. However, its complex electromechanical structure and the coupling relationship between the subsystems make it difficult to control its operation process accurately. In this paper, the voltage control decoupling method is used to decouple the torque and suspension system of a bearingless motorized spindle with an independent inverse system, then control the systems. Finally, the control of decoupled bearingless motorized spindle is simulated. The results show that when the speed, rotor radial displacement, and rotor flux change respectively, they will not influence each other. The speed and radial displacement are unaffected after the sudden load is applied. It proves the effectiveness of the decoupling control method.

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