Smart energy and electricity networks are a crucial component in building smart city architectures; their consistent and harmonized inclusion in the smart city design should be carefully considered through a detailed analysis of the impacts (environmental, energy, economic, societal) and the implementation of cost benefit analysis (CBA), not only in terms of managing the grid itself but also in a wider perspective that includes environmental, security, and social aspects. This paper first discusses the main impact that smart grid deployment has, in different respects, in smart cities and then presents a methodology for an extended CBA, able to go beyond the strictly financial aspects. It is based on previous developments at the European level. The methodology conceptually illustrated can naturally be extended to the assessment of proposals for the development of smart cities.
Two basic schemes of synchronized pulsewidth modulation (PWM) have been disseminated for control of dual inverter-fed open-end winding induction motor drives with full elimination of the common-mode voltages. The algorithms of synchronized PWM provide symmetry of the phase voltage of the system during the whole control range including the zone of overmodulation. Spectra of the motor phase voltage of dual inverter-fed drives do not contain even harmonics and sub-harmonics (combined harmonics), which is especially important for the systems with increased power rating. Analysis of processes in drive systems with two schemes of synchronized PWM, based on the modelling and simulations, has been done
1 October 2006 in 2007 IEEE Industry Applications Annual Meeting
Novel method of synchronized pulse width modulation (PWM) has been disseminated for control of cascaded neutral-point-clamped inverters feeding open-end winding induction motor drive with single dc voltage source. Control algorithms provide in this case full elimination of the common-mode voltages both in each inverter and in the load. Phase voltages of the drive system are characterised by quarter-wave symmetry during the whole control range including the zone of overmodulation, and its spectra do not contain even harmonics and sub-harmonics. Simulations give the behaviour of the systems with synchronized PWM in both undermodulation and overmodulation zones. Continuous, discontinuous and "direct-direct" schemes of synchronized PWM, applied for control of cascaded three-level converters, have been analyzed and compared
The challenge of worldwide energy decarbonization is crucial to ensure sustainable development. The achievement of decarbonization encompasses not only a considerable exploitation of renewable energy sources, but also a paradigm shift in final energy uses towards their massive electrification. Electrification based on Global Energy Interconnections (GEI) is one of the possible pathways towards decarbonization in energy systems. In this paper, we critically discuss the idea of decarbonization through global interconnections in an ‘electricity based’ world, contrasting it against the typically desirable attributes for energy in terms of security, efficiency, sustainability, and affordability. We provide a comparative analysis of global interconnection with other internationally proposed visions of future energy scenarios. The analysis shows that the GEI option could be particularly beneficial from an environmental point of view; however, it requests deep and relevant modifications in the energy markets and regulations, in which a common framework based on the cooperation among different countries is needed.