This paper proposes a method for designing a robust full-order observer for vector-controlled induction motors taking core loss into account. Although conventional research focuses on parameter identification, global stability of the identification remains questionable. Therefore, robustness against some parameters is required. This paper describes the design of a robust full-order observer which takes core loss into account, using both the gain-scheduled H/sub /spl infin// control and the linear matrix inequality technique. This design always results in a stable controller. The robustness of the proposed method against variations of resistances is evaluated by experiments. 相似文献
We propose a dynamic mobility management framework for Internet Protocol version 6 (IPv6) and policy enforcement enabled heterogenous
wireless networks. Policies and policy rules are defined depending on network infrastructure facilities, service agreements
and negotiation results. Each traffic is coupled with an identifiable traffic flow while the heterogenous interface flow bindings
are regulated by polices. The network selection, flow distribution, handovers and mobility procedures are flexible and we
propose to improve the decision making via Multiple Attributes Decision Making (MADM). Techniques considered in the framework
include the IPv6 based Network Mobility (NEMO), multihoming capability, transparent vertical handovers, horizontal handovers
and dynamic policy enforcement matching process to improve the Quality of Service (QoS), Quality of Experience (QoE) and ubiquitous
connectivity. A experiment testbed and simulation models have been constructed to verify the mobility framework performance
in a heterogeneous WiFi, WiMax and UMTS hybrid environment. 相似文献
Recovered carbon black (rCB), a very economical and abundance source of material, is transformed into dazzling multicolour fluorescence and visual display for the first time by way of a scanning focused laser treatment. This laser-initiated process is both straightforward and versatile, catering to both micro- and macro-scopic patterning with the sample in ambient or helium environment. The observed phenomenon is attributed to both chemical and structural induced colouration of rCB powder. Chemically, carbon infusion of oxidised metal occurs when photothermal reaction takes place in ambient. After laser modification with the sample in helium environment, the powder not only fluoresces due to sulphur impurities, control annealing of these powders results in formation of periodic arrangements of carbon nanoparticles. The periodicity of these arrangement falls within the range of visible wavelength, hence contributing to the visually observable rainbow coloured rCB flakes. The patterned sample is also transferrable using PDMS stamps. This in turn broadens the application of this material in flexible electronic devices/displays. Photocurrent measurements show most significant enhancement under yellow light illumination. Furthermore, in the presence of an applied potential, the fluorescence detected from the sample can easily be switched off. All in all, we present a simple process to add multiple functionalities to a material that is both inexpensive and sustainable.
In this paper, we evaluate the difference between the slip-frequency type and the flux-feedback type in discrete time. Both vector control systems in discrete time, designed equivalently in continuous time, have different discretization errors. In a large sampling time region, the slip-frequency type (using the induction motor rotor-flux frame model) is less influenced by the discretization error than the flux-feedback type (using the stator frame model). In this sense, the slip-frequency type is superior to the flux-feedback type, but the stator frame model is linear and the rotor-flux frame model is nonlinear. With the flux-feedback type using the stator frame, it is easier to design the controller and the observer. Therefore, we believe that the vector controller and the observer should be designed using the stator frame model and that, after it is transformed to the rotor-flux frame model, it should be implemented 相似文献