Visvakumar Aravinthan

Wireless AMI application and security for controlled home area networks

Compared to the conventional grid, the smart grid requires active participation of consumers to improve the quality and reliability of power delivery. Advanced metering infrastructure (AMI), commonly known as the smart meter, which has the capability of supporting various functions beyond that of recording energy usage, will facilitate this expected increase in consumer participation. Another primary benefit of AMI is load and cost management for the utility. AMI requires a reliable communication system between the smart meter and consumer equipment. This paper identifies wireless networking solutions such as ZigBee as the best mode for such communication. Due to the shared nature of the wireless medium, however, these deployments face security challenges and interference issues. These must be addressed, taking into account the interests of both the utility and the consumer. This paper takes a comprehensive look at wireless security in the AMI based home-area network by identifying a wide range of possible vulnerabilities. Countermeasures that can be used by both the utility company as well as the customer are developed.

Wireless communication for smart grid applications at distribution level — Feasibility and requirements

Smart grid technology places greater demands for reliability on communications infrastructure. This work focuses on identifying requirements for distribution feeder level communications. Due to the large number of distribution components connected to the distribution level feeders, a massively deployed wireless communication network is identified as the potential technology for this application. This network would allow prioritized communication: high priority for abnormal events and system control operations, and low priority communication for asset management tasks. A three-layer wireless communication architecture is proposed in this work to increase the reliability and reduce the latency of event notification. Fault location is considered as an example application to illustrate the proposed architecture.

Toward a Secure Wireless-Based Home Area Network for Metering in Smart Grids

Compared to the conventional grid, the smart grid requires active participation of consumers to improve the quality and reliability of power delivery. The increase in consumer participation is expected from the advanced metering infrastructure (AMI), commonly known as the smart meter, which has the capability of supporting various functions beyond that of recording energy usage. One of the primary objectives of the AMI is to allow load and cost management for the utility. This is envisioned partly through a communication system implemented between the smart meter and consumer equipment, currently deployed using wireless networking solutions such as ZigBee. Due to the shared nature of the wireless medium, however, these deployments face security challenges and interference issues, which must be addressed, taking into account the interests of both the utility company and the consumer. This work takes a comprehensive look at wireless security in the smart-meter-based home area network scenario and identifies possible vulnerabilities. Subsequently, some countermeasures are developed that can be used by both the utility company and the customer and are integrated into a common framework called SecureHAN that can be agreed to by both. In addition, the experiences from implementing the SecureHAN framework using commercial off-the-shelf hardware are described, including possible challenges.

Probabilistic modeling of EV charging and its impact on distribution transformer loss of life

The effect of uncontrolled electric vehicle (EV) charging on the distribution side is considerable and has the potential to affect the life of distribution components. This especially has significant impact on secondary-distribution transformers in residential zones. With smart grid implementation, assessment for reliability of feeder-level components becomes more crucial. This work analyzes the distribution-level secondary transformer loss of life as the result of EV charging. Different charging patterns are developed using a probabilistic model for vehicle arrival time and charge left at arrival. A number of different scenarios, such as residential loading, weather patterns, and geographical locations, are considered in analyzing the effects.

Distributed Estimation in a Power Constrained Sensor Network

This paper derives the optimum non-uniform quantization scheme for a distributed estimation problem based on noisy observations in a wireless sensor network. The optimal quantization scheme minimizes the mean squared estimation error subjected simultaneously to both a total system power as well as individual node power constraints. According to the derived optimal scheme, sensors with poor signal-to-noise ratios (SNR) refrain from transmitting their observations. The rest of the sensors transmit their quantized observations. The number of quantized bits depends on the SNR and the maximum power constraint at each node. The numerical results show that compared to a uniform power allocation scheme, the proposed scheme achieves significantly smaller mean squared error (MSE) for the same average power consumption

Controlled Electric Vehicle Charging for Mitigating Impacts on Distribution Assets

This paper proposes a two-step methodology for scheduling electric vehicle (EV) charging, which limits the burden on distribution and transmission assets while ensuring all the vehicles are charged. In the first step, the number of vehicles to be charged during each hour is optimized based on day-ahead requests for charging. The second step determines the maximum number of vehicles that can be charged based on operating conditions during the next hour to ensure distribution reliability requirements are met. A numerical example is given to illustrate the EV charging management scheme. This technique will limit the effects of EV charging on distribution assets.

Feeder level power loss reduction through reactive power control with presence of distributed generation

Distributed generation is one of the biggest changes that the power industry is facing with the mitigation of greenhouse gases and the smart grid initiative. With the presence of a communication infrastructure, it is expected that distributed generators could be more efficiently operated. This work focuses on developing a power loss minimization technique while allowing distributed resources to supply reactive power. The proposed technique is tested using IEEE 13- and 34-node test feeders, and results show that the proposed technique will minimize real power loss in radial distribution feeders.

Electric vehicles as configurable distributed energy storage in the smart grid

Studying the impact of PHEVs/BEVs is quite complex since no other approach before had the unique capability of acting as dispersed and yet mobile energy storage that may be aggregated at different scales. This paper aims at demonstrating the potential benefits of using electrical vehicles (EVs) as distributed energy storage systems in smart grid. It discusses the options of grid-to-vehicle (G2V) and vehicle-to-grid (V2G) operating modes that might be used to support the power grid through demand side management (DSM) program. The battery charging performance, implementation and benefits of using EVs as distributed energy storages for demand-side management are discussed and demonstrated with test cases.

Integration of asset and outage management tasks for distribution systems

Integration of asset management and outage management tasks for distribution system is proposed and discussed. The necessity of integration is presented, followed by a description of the concept of integration. The optimization of asset and outage management tasks based on the integrated processing and evaluation of the influence of optimization on the cost of system outage is elaborated. Potential benefit of integration in distribution system is analyzed in terms of system reliability and return of investment for utilities.

Strategies of residential peak shaving with integration of demand response and V2H

Plug-in electric vehicles (PEVs) have the potential to be used as storage devices to mitigate some of the grid level impacts, especially at the residential level. Since primary usage of electric vehicle battery is for transportation, it is important to optimize the life of the battery and energy discharge to the grid (V2G). The smart grid initiative requires active consumer participation through demand side management. Proper V2G application combined with demand response (DR) could improve some of the system level concerns such as peak shaving and flexible loading. This work proposes a vehicle-to-house (V2H) charge management based on demand side management scheme to minimize the peak loading at each individual house using a model based control design. GridLab-D is used to evaluate the model which shows such a scheme has the potential to reduce the peak.