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This paper presents a hierarchical control system to mitigate the variability of solar photovoltaic (PV) power plant and provide ancillary services to the electric grid without the need for additional non-solar resources. With coordinated management of each inverter in the system, the control system commands the power plant to proactively curtail a small fraction of its instantaneous maximum power potential, which gives the plant enough headroom to ramp up production from the overall power plant, for a service such as regulation reserve. This control system is practical for continuously changing cloud cover conditions in partially cloudy days. A case study from a site in Hawaii with one-second resolution solar irradiance data is used to verify the efficacy of the proposed control system. The proposed control algorithm is subsequently compared with the alternative control technology from the literature, the grouping control algorithm; the results show that the proposed hierarchical control system is over 10 times more effective in reducing generator mileage to support power fluctuations from solar PV power plants. [ABSTRACT FROM AUTHOR]

Present distribution grids generally have limited sensing capabilities and are therefore characterized by low observability. Improved observability is a prerequisite for increasing the hosting capacity of distributed energy resources such as solar photovoltaics (PV) in distribution grids. In this context, this paper presents learning-aided low-voltage estimation using untapped but readily available and widely distributed sensors from cable television (CATV) networks. The cable broadband sensors offer timely local voltage magnitude sensing with 5-minute resolution and can provide an order of magnitude more data on the time-varying state of a secondary distribution system than currently deployed utility sensors. The proposed solution incorporates voltage readings from neighboring CATV sensors, taking into account spatio-temporal aspects of the observations, and estimates single-phase voltage magnitudes at all non-monitored low-voltage buses using random forests. The effectiveness of the proposed approach was demonstrated using a multi-phase 1572-bus feeder from the SMART-DS data set for two case studies - passive distribution feeder (without PV) and active distribution feeder (with PV). The analysis was conducted on simulated data, and the results show voltage estimates with a high degree of accuracy, even at extremely low percentages of observable nodes. [ABSTRACT FROM AUTHOR]

Solar photovoltaic (PV) is a prominent technology for the generation of electricity and its utility is on the rise. The PV-based generation facilities are susceptible to faults which if mismanaged, can result in an interruption in the supply of load demand and damage to the system. Faults in PV systems are caused by a broad range of reasons and hence, it is crucial to situate a fault-tolerant system for reliable operation. This study proposes a fault-tolerant control strategy for power electronics inverters for the integration of PV systems into power systems. This is a supervisory mechanism designed to aid PV systems to continue their operation during faults. A computer simulation verifies the performance of the proposed control strategy under a series of common fault conditions assuming a wide range of configurations for the PV system and load variations. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for a small-signal stability analysis of large-scale power systems in response to variability of offshore wind power plants. This study considers the variability of wind power as the source of disturbance introduced to the system. To accomplish this goal, a singular value decomposition-total least squares extended Prony analysis is used to assess the small-signal voltage stability. In addition, a swing-based frequency response metric is used to assess the small-signal frequency stability. The case study here considers the integration of a 1000-MW offshore wind power plant, operating in Lake Erie, into the FirstEnergy/PJM service territory. This study uses a realistic model of the 63 000-bus test system that represents the U.S. Eastern Interconnection. The results verify the utility and practicality of this methodology for the integration studies of offshore wind power plants. [ABSTRACT FROM AUTHOR]

Information on the sixth annual Inter-Continental Advanced Materials for Photonics held in South Africa from June 15-29, 2014 is presented. Professor Ivan Smalyukh provides an overview of the history if soft matter. Professor Jonathan Selinger discusses the theory of nanoparticle suspensions, liquid crystals and soft material-related topics. Professor Robin Selinger explains the simulation defects and applications of soft matter.

Information on the fifth Inter-Continental Advanced Materials for Photonics (I-CAMP'13) that was held in Cambridge, England from June 26-July 6, 2013 is presented. Various issues discussed in the conference includes renewable energy, educational tools and role of chirality in liquid crystals. The conference was attended by various people including Ivan Smalyukh from the University of Colorado, Mark Warner and Timothy Wilkinson from the University of Cambridge.

This paper tackles the key challenges for dynamics, control, and automation of power systems that are imposed by the integration of renewable power plants. First, the current practice of automation and control in large‐scale power systems are reviewed. Then, dynamics and control of electrical transmission systems are discussed and the issues associated with the integration of large‐scale wind and solar power plants are exploited. The discussion carries on with a focus on control of electrical distribution systems and the key issues associated with the integration of distributed generation power plants. An emerging concern in power and energy industry is the dynamic interaction between transmission and distribution systems as a result of technological and topological changes in power systems that can put their control at risk. These topics are also covered in this paper. In terms of automation, the key challenges and opportunities for accommodation of higher penetration and share of renewable energy, as part of the vision for grid modernization, are explored in this paper. Throughout the discussion, some results from the recent studies are shown. This article is categorized under:Energy Infrastructure > Systems and Infrastructure The key challenges for dynamics, control, and automation of future power systems are explored in this paper. [ABSTRACT FROM AUTHOR]