The integration of the various types of distributed generators in low-voltage (LV) distribution networks becomes a great concern, especially the rooftop photovoltaic (PV) systems. The negative impacts of the rooftop PVs on the distribution feeder buses’ voltage include voltage rise and voltage unbalance (VU). Such a voltage-violation condition depends mainly on the PVs ratings and the network unbalance percentage. This study presents a review for different techniques used to mitigate the voltage violation resulting from PVs integration in a typical three-phase four-wire LV distribution network case study. The voltage-violation mitigation techniques studied in this study are enhancement of the feeder, on-load tap changer, demand-side management, active power curtailment, a reactive power control, static transfer switch, energy storage systems and hybrid strategies. The LV distribution network case study was modelled based on constant power model method using MATLAB software environment. The simulation results demonstrate both voltage regulation and alleviating VU capabilities of each technique.

Efficiency and reliability have been essential requirements for energy generation in smart cities. This study presents the design and development of dependable control schemes for microgrid management, which can be seamlessly integrated into the management system of smart buildings. Here, to recover from failures in the solar energy system of a building microgrid, dependable controllers are proposed along with their hardware implementation. The system features the use of Internet of Things (IoT) as its core to coordinate the operation of multiple subsystems in a scalable manner. The control scheme uses a number of controllers cooperatively functioning via a token-based mechanism within the network to provide redundancy and thus reliability in solar tracking. The system exploits data from not only local in-situ sensors but also online sources via IoT networks for fault-tolerant control. Experiments conducted in a 12-storey building indicate that the harvested solar energy meets the design requirement while the control reliability is maintained in face of communication or hardware disruptions. The results confirmed the validity of the proposed approach and its applicability to energy management in smart buildings.

Temperature and humidity play an extremely important role in indoor thermal comfort and industrial production. To achieve precise control of temperature and humidity in the building space environment and reduce energy consumption, it is necessary to analyse turbulence from the perspective of energy. On the basis of the basic principle of building energy enthalpy, under the premise of reasonable assumptions of various boundary conditions, four turbulence models were established for simulation. The basic characteristics, overall distribution and local characteristics of the interior energy enthalpy were compared and analysed. The theory of building energy enthalpy not only can effectively solve the influence of latent heat on the building environment, but also can provide guidance on the selection strategy of turbulence models. The proposed theory can improve the accuracy and credibility of the simulation data of building space.

The number of electric vehicles (EVs) is expected to increase significantly in the future to combat air pollution and reduce reliance on fossil fuels. This will impact the power system. However, with appropriate charging and discharging through vehicle-to-grid (V2G) operation, EV batteries could replace some stationary energy storage to provide support for the power system and benefit EV owners. This raises the questions of when and how EV battery storage should be dispatched, taking into account both vehicle users' and power system requirements and priorities, as well as the constraints of the battery system. This chapter proposes a decentralized dispatch strategy based on the analytic hierarchy process (AHP) taking into account the relative importance of the different criteria such as cost, battery state of charge (SOC), power system contingency and load levelling. The proposed ARP -based dispatch strategy is tested on an IEEE Reliability Test System (RTS) with different EV numbers and capacities to investigate the efficacy of such an approach. The simulation results demonstrate the feasibility and benefits of the strategy.

Commercial fleet of electric vehicles (EV) is serving clients for different purposes, but each of those services is requiring some time to be fulfilled. When the vehicle is charging or discharging using the vehicle-to-grid (V2G) concept, the waiting time to service increases, and the vehicle owner is suffering losses due to the reduced service quality. In this chapter, we are exploring the scheduling optimization problem of an EV fleet controlled by the aggregator. The optimization of vehicle daily scheduling is needed in order to increase the revenues from offering ancillary services and reduce costs of service quality loss. New, practical multi-criteria decision-making methodologies for the daily scheduling of EV fleet are proposed. Criteria that have to be fulfilled simultaneously are the minimization of the service waiting time (SWT), maximization of the revenues coming from the frequency regulation services and the minimization of the costs incurred by the vehicle charging, including the costs of battery degradation. The stochastic nature of vehicles driving patterns (time the car owner has to calculate for the service provision) is considered using the queuing theory. The proposed methodology has been successfully implemented on two cases of EV commercial fleet daily scheduling.

Mobile communication systems rely on radiofrequency waves to operate. Given the popularity and ubiquity of mobile communication devices as well as network densification, the level of Electromagnetic Field (EMF) exposure to the public is expected to rise significantly over the next few years. Although there is no clear evidence linking short-term exposure to EMF emission from wireless communication systems with adverse health effects, the International Agency for Research on Cancer (IARC) has concluded that EMF radiation is possibly carcinogenic. To cope with the concerns of the general public, the European Environmental Agency has recommended non-technical precautionary approaches to minimize exposure to EMF emissions. Rather than relying on these non-technical approaches, EMF, latency, network resilience and connection density, alongside traditional criteria such as spectral efficiency and energy efficiency are expected to take centre stage in the development of 5G systems. This book focuses on innovative EMF exposure research for future generations of mobile and wireless communications. This timely publication highlights the novel work done on reducing EMF emissions in future mobile communication systems and how to develop smart integrated technical solutions.

This study presents a new energy-efficient design for static random access memory (SRAM) using a low-power input data encoding and output data decoding stages. A data bit reordering algorithm is applied to the input data to increase the number of 0s that are going to be written into the SRAM array. Using SRAM cells which are more energy-efficient in writing a ‘0’ than a ‘1’ benefits from this, resulting in a reduction in the total power and energy consumptions of the whole memory. The input data encoding is performed using a simple circuit, which is built of multiplexers and inverters. After the read operation, data will be returned back to its initial form using a low-power data decoding circuit. Simulation results in an industrial and a predictive CMOS technology show that the proposed design for SRAM reduces the energy consumption of read and write operations considerably for some standard test images as input data to the memory. For instance, in writing pixels of Lenna test image into this SRAM and reading them back, 15 and 20% savings are observed for the energy consumption of write and read operations, respectively, compared with the normal write and read operations in standard SRAMs.

Design of a novel phase frequency detector (PFD) has been presented here. The innovative advantage of the proposed structure is its improved dead zone performance due to the architectural simplicity which is a combination of static and pass transistor logic (PTL)-based latch configuration. Due to low latency from inputs to the outputs, the operating frequency of the proposed circuit is high while its power consumption is very low. Analytics along with simulations have confirmed the correct behaviour of the designed circuit. For better evaluation of designed architecture advantages, two of the last reported works have been redesigned and simulated along with the proposed PFD. The post-layout simulation results using HSPICE with TSMC 0.18 µm CMOS technology and 1.8 V power supply demonstrate the operating frequency of 1 GHz for the designed circuitry while the power dissipation is 277 µW and the measured dead zone is as an enormous enhancement over previous works.

The effect of radiation on digital circuits in particularly complementary metal oxide semiconductor (CMOS) technology has been known since many years. The two most important radiation effects are total ionisation dose and single-event effects (SEEs). The complexity of circuit will increase depends on the number of gate inputs, which degrades the radiation to accelerate the total dose levels. The incremental dose level affects the circuit parameter failure, which affects the functionality of logic design. Many authors focus to reduce radiation effects with avoid function loss, but those extra efforts consume more power. In this study, a low power radiation aware circuit design is proposed. First, the physics-based modelling approach is used for compute radiation response of each component in the circuit. Tri-state inverter embedded non-clocked gating technique is proposed to eliminate unwanted latches and disables the inverter chain when the input data are kept unchanged, so redundant transitions of delayed clock signals. For simulation purpose, the authors applied their proposed technique in flip–flops and make it as more aware of radiation effects and power consumption. The performance of the proposed circuit design is analysed at 16 nm CMOS predictive technology model in terms of power delay product using HSPICE tool.

Using conventional memory technologies, for example, static random access memory (RAM) (SRAM), dynamic RAM (DRAM) and flash memory, it is difficult to fulfill the market requirements for higher density and lower power dissipation [1]. Therefore, semiconductor organizations are thinking that it is difficult to supply the expanding market interest for the higher density and lower power nonvolatile memories [2]. The recent invention of memristor device has given hope to semiconductor organizations by offering a less demanding approach to expand the density by utilizing the current fabrication technology [3]. This is conceivable on the grounds that memristor devices just require two terminals to work, which utilize less wafer space, reduce the complexity of circuit interconnections and encourage highdensity integration when used as a part of crossbar structures [4-7]. Besides all these features of memristor, it also has some additional characteristics like low power and non-volatility [8]. But the main limitation of the memristor-based memory cell is its slow write time access [9]. Transmission gate is capable of providing rail-to-rail swing and can easily pass both logic “0” and logic “1” [10]. These advantages help to overcome the problem of slow write time access of memristor. The objective of this chapter is to understand what a memristor is and how can a memristor be modeled for its current-voltage (I-V) characteristics. Further, this chapter deals with the concepts of transmission gates, then using the designed memristor and transmission gates, a DRAM cell was designed. The designed memory cell was simulated using HSPICE tool. The result shows that the memristor-based DRAM cell can replace the conventional memory cell in future to achieve higher density and lower power dissipation.