Zhong Fan

Smart Grid Communications: Overview of Research Challenges, Solutions, and Standardization Activities

Optimization of energy consumption in future intelligent energy networks (or Smart Grids) will be based on grid-integrated near-real-time communications between various grid elements in generation, transmission, distribution and loads. This paper discusses some of the challenges and opportunities of communications research in the areas of smart grid and smart metering. In particular, we focus on some of the key communications challenges for realizing interoperable and future-proof smart grid/metering networks, smart grid security and privacy, and how some of the existing networking technologies can be applied to energy management. Finally, we also discuss the coordinated standardization efforts in Europe to harmonize communications standards and protocols.

A Distributed Demand Response Algorithm and Its Application to PHEV Charging in Smart Grids

This paper proposes a distributed framework for demand response and user adaptation in smart grid networks. In particular, we borrow the concept of congestion pricing in Internet traffic control and show that pricing information is very useful to regulate user demand and hence balance network load. User preference is modeled as a willingness to pay parameter which can be seen as an indicator of differential quality of service. Both analysis and simulation results are presented to demonstrate the dynamics and convergence behavior of the algorithm. Based on this algorithm, we then propose a novel charging method for plug-in hybrid electric vehicles (PHEVs) in a smart grid, where users or PHEVs can adapt their charging rates according to their preferences. Simulation results are presented to demonstrate the dynamic behavior of the charging algorithm and impact of different parameters on system performance.

Emerging technologies and research challenges for 5G wireless networks

As the take-up of Long Term Evolution (LTE)/4G cellular accelerates, there is increasing interest in technologies that will define the next generation (5G) telecommunication standard. This article identifies several emerging technologies which will change and define the future generations of telecommunication standards. Some of these technologies are already making their way into standards such as 3GPP LTE, while others are still in development. Additionally, we will look at some of the research problems that these new technologies pose.

An integer linear programming based optimization for home demand-side management in smart grid

We propose a consumption scheduling mechanism for home area load management in smart grid using integer linear programming (ILP) technique. The aim of the proposed scheduling is to minimise the peak hourly load in order to achieve an optimal (balanced) daily load schedule. The proposed mechanism is able to schedule both the optimal power and the optimal operation time for power-shiftable appliances and time-shiftable appliances respectively according to the power consumption patterns of all the individual appliances. Simulation results based on home and neighbourhood area scenarios have been presented to demonstrate the effectiveness of the proposed technique.

Overview of demand management in smart grid and enabling wireless communication technologies

There are significant challenges as well as great opportunities for research at both policy and technology levels on the efficient use of energy. Most existing power generation and distribution systems are based on a century old mechanism where power grids are managed by vertically integrated utilities. Intelligent power grids known as smart grids are required as the demand for energy continues to grow and more and more emphasis is being placed on the supply of renewable energy. The main ingredient of smart grids is the integration of information and communication technology (ICT) into the grids to monitor and regulate power generation and demand. This article provides an overview of demand management with a particular focus on the necessary enabling wireless technologies. Various mechanisms and algorithms for the optimal demand management in smart grids using these wireless technologies are also reviewed.

Reinforcement learning based spectrum-aware routing in multi-hop cognitive radio networks

Routing in multi-hop cognitive radio networks (CRN) should be spectrum-aware. In this paper, two adaptive reinforcement learning based spectrum-aware routing protocols are introduced. Q-Learning and Dual Reinforcement Learning are applied respectively for them. The cognitive nodes store a table of Q values that estimate the numbers of available channels on the routes and update them while routing. So they can adaptively learn good routes which have more available channels from just local information. Compared to the previous spectrumaware routing protocols in multi-hop cognitive radio networks, they are simpler and easier to implement, more cost-effective, and can avoid drawbacks in on-demand protocols but still keep adaptive and dynamic routing. Both of our protocols perform better than the spectrum-aware shortest path protocol when network load is not too low. In the meantime, spectrum-aware DRQ-routing learns the optimal routing policy 1.5 times as fast as the spectrum-aware Q-routing at low and medium network load. It also learns a routing policy which is more than seven times as good as that of spectrum-aware Q-routing at high network load.

The tradeoff between energy efficiency and system performance of femtocell deployment

In this paper1 we discuss some of the benefits and challenges of deploying femtocells in a cellular network. In particular, we focus on the tradeoff between energy efficiency and system performance. With realistic LTE system parameters, we have shown that femtocells can indeed improve energy efficiency of the network. However, this comes with a price — performance degradation due to interference, which is especially severe in dense deployment scenarios. Therefore, femtocell solutions are “green”, but also “noisy”. Interference mitigation mechanisms such as power control, mobility management, and resource allocation are then discussed.

An integer linear programming and game theory based optimization for demand-side management in smart grid

We propose a consumption scheduling mechanism for home and neighbourhood area load demand management in smart grid using integer linear programming (ILP) and game theory. The proposed mechanism is able to schedule both the optimal power and the optimal operation time for power-shiftable appliances and time-shiftable appliances respectively according to the power consumption patterns of all the individual appliances. Simulation results for both the centralised and the distributed management scenarios have been presented to demonstrate and verify the effectiveness of the proposed technique.

M2M Communications in the Smart Grid: Applications, Standards, Enabling Technologies, and Research Challenges

We present some of the ongoing standardisation work in M2M communications followed by the application of machine-to-machine (M2M) communications to smart grid. We analyse and discuss the enabling technologies in M2M and present an overview of the communications challenges and research opportunities with a focus on wireless sensor networks and their applications in a smart grid environment.

Access and Handover Management for Femtocell Systems

In this paper a simple and effective method has been proposed to perform access and handover management for femtocell systems. Firstly an analysis on interference impact on femtocells has been provided. Then we explore several techniques to address the interference problem between CSG (closed subscriber group) femtocell and macrocell. When a non-CSG MS comes close to the femtocell in question, the macrocell BS makes the decision (based on the CSG access list exchanged from the femtocell) that unnecessary handover will not be initiated, saving radio resource and signaling load on the network. At the same time various proactive interference mitigation mechanisms can be operated. A hybrid access mode and a femtocell-initiated handover procedure with adaptive threshold have also been discussed.