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With growing applications for protection, control, monitoring and measurement systems for power system applications, the necessity for very reliable and accurate frequency and phase angle measurement of the power system voltage is also growing. This paper describes a linear phase locked loop for three phase systems for precise measurement of the frequency and phase angle of the line voltage. However,...
The paper provides an overview of global activities associated with harnessing ocean renewable energy resources for generating electricity as well as for other utilizations. Developmental status and maturity of various conversion technologies to harness energy from tides, waves, tidal stream, ocean currents, temperature gradient, and salinity gradients are presented.
Currently, the New England power system is highly dependent on fossil fueled generating units. The region has a significant potential for developing renewable sources of energy, including substantial inland and offshore wind resources within the region as well as in neighboring areas. ISO New England (ISO-NE) has identified the potential for up to 12,000 megawatts of wind resources within New England...
This paper presents both quantitative and qualitative analysis of several polarization based measurements, which include frequency domain spectroscopy (FDS) and polarization depolarization current (PDC) measurements on four different field transformers. The X-Y model and the RC circuit model are mainly used in the analyses. In this study sequential FDS/PDC measurements on the same unit are used to...
This paper describes research in progress for a panel session presentation on how phasor measurement unit (PMU) values can be used to improve power system operations beyond their use in state estimation.
Summary form only given. Alabama Power Company has an ongoing program to improve the voltage profile of the 115 kV transmission system. This program includes the installation of a large number of distribution line capacitors. Initially, the distribution line capacitors were installed in the traditional fashion as fixed installations. However, with the wide spread deployment of Distribution Automation,...
The strive for sustainable energy systems will most likely lead to an increased use of renewable energy sources which to a large extent are fluctuating. Therefore, a larger demand for balancing capacity will be required to maintain system security. Plug-in Hybrid Electric Vehicles (PHEV) represent a potential storage which could offer additional balancing power. Here, the applicability of PHEVs for...
A methodology to solve the network expansion planning problem considering N-1 security criterion is proposed. The main idea to achieve the desired results is to separate the whole problem into two subproblems and solve them iteratively. The aim of upper level problem is to solve the mixed-integer programming model with all identified constraints. For the lower level problem, all N-1 contingencies...
This paper presents the analysis of unique features and classification method for identifying the root cause of overhead distribution fault events. In particular, the paper focuses on faults caused by animal contacts, tree contacts and lightning-induced disturbances. The proposed methodology is implemented and tested using 148 real-world fault events. The methodology has a classification rate of 90%,...
This article discusses the impact that communication will have on the electric power grid in the future. Recent efforts, such as UCA 2.0 and IEC 61850, are establishing a standard way for electric power substations, intelligent electronic devices, and other apparatus to communicate over data networks. These efforts pave the way to a future where protection and control of the electric power grid will...
In this paper, a dynamic power limiter at the point of common coupling (PCC) of a micro-grid is proposed. A 60Hz, step-down transformer is generally used at the PCC to connect the micro-grid to the power system grid. Substitution of the conventional 60Hz transformer by a dynamic power limiter has the following advantages: 1) Bi-directional active-power control capability at the PCC which results in...
Squirrel-cage induction motors are replacing DC motors in variable speed applications due to the availability of advanced control techniques such as Direct Torque Control and Field Oriented Control. At part-load operation of an induction machine, the core losses and, to some extent, copper losses can be minimized, if the machine is operated at a reduced value of flux rather than at the rated value...
This paper reviews six IVGTF tasks related to interconnection and operating requirements, and provides a report on their objectives, milestones and status. The three interconnection tasks are: Interconnection Requirements Enhancement (Task 1.3); Low Voltage Ride-Through (LVRT) Requirements (Task 1.7); and Balancing Authority (BA) Communications (Task 2.2). The three operating tasks are: Incorporating...
This paper discusses a study funded the California Energy Commission (CEC), performed by New Power Technologies with Southern California Edison to validate a system-wide, distribution element-level (high definition) power system simulation using field measurements. Comparisons of system simulation results and field measurements showed that the simulation is a statistically significant predictor of...
The outage of a line due to a fault can be expensive, hence the fault has to be cleared as fast as possible. Digital protection relays consist of fault locators based on several methods. Due to the availability of highly accurate GPS based time references the investigation of two-terminal methods combined with signal analysis tools makes sense in the first place. The aim of this paper is to develop...
This paper presents a comprehensive optimization method for the diagnosis of large substation steel grounding grid integrity status, and the detection and location of any corrosion spot before digging out the grounding grid. A grounding grid is modeled as a circuit network, and fault diagnosis equations are derived by applying Tellegen's theorem, optimization theory and fault diagnosis theory for...
This paper proposes an approach for the control and optimization of power flow by integrating Plug-In Hybrid Vehicles (PHEV) to an existing residential photovoltaic system. Optimization of Power flow reduces the dependency for electric power from the grid and control involves determining the source from which residential load will be catered. The system built to achieve the goal is a combination of...
Improvements in transmission and distribution networks can be noticed in most countries that had their system architecture changed by the deregulation process. In this new environment one of the biggest challenges is the transmission and distribution open access. In Brazil, the National Electricity Regulatory Agency has established that the monthly amount of transmission system usage contracted by...
Demand response (DR), coupled with smart-grid technologies, will be a big initiative for energy companies in the US for the next 3-5 years. This paper summarizes the key technical and IT challenges that will need to be solved to properly deploy DR at the wholesale and retail levels.
Ensuring system reliability and security while operating electricity markets is the primary responsibility of independent system operators. Maintaining system security in real-time is a significant challenge due to limited time frame permitted for analyzing and responding to security issues. This paper focuses on the applications designed to address static security in the real-time operations of ERCOT...
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