skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Network Reduction Algorithm for Developing Distribution Feeders for Real-Time Simulators: Preprint

Abstract

As advanced grid-support functions (AGF) become more widely used in grid-connected photovoltaic (PV) inverters, utilities are increasingly interested in their impacts when implemented in the field. These effects can be understood by modeling feeders in real-time systems and testing PV inverters using power hardware-in-the-loop (PHIL) techniques. This paper presents a novel feeder model reduction algorithm using a Monte Carlo method that enables large feeders to be solved and operated on real-time computing platforms. Two Hawaiian Electric feeder models in Synergi Electric's load flow software were converted to reduced order models in OpenDSS, and subsequently implemented in the OPAL-RT real-time digital testing platform. Smart PV inverters were added to the real-time model with AGF responses modeled after characterizing commercially available hardware inverters. Finally, hardware inverters were tested in conjunction with the real-time model using PHIL techniques so that the effects of AGFs on the choice feeders could be analyzed.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Grid Modernization Laboratory Consortium
OSTI Identifier:
1364143
Report Number(s):
NREL/CP-5D00-67400
DOE Contract Number:
AC36-08GO28308
Resource Type:
Conference
Resource Relation:
Conference: To be presented at the 2017 IEEE Power and Energy Society General Meeting, Chicago, Illinois, 16-20 July 2017
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 24 POWER TRANSMISSION AND DISTRIBUTION; advanced grid-support functions; power hardware-in-the-loop simulation; network reduction; real-time simulator; smart PV inverter

Citation Formats

Nagarajan, Adarsh, Nelson, Austin, Prabakar, Kumaraguru, Hoke, Andy, Asano, Marc, Ueda, Reid, and Nepal, Shaili. Network Reduction Algorithm for Developing Distribution Feeders for Real-Time Simulators: Preprint. United States: N. p., 2017. Web.
Nagarajan, Adarsh, Nelson, Austin, Prabakar, Kumaraguru, Hoke, Andy, Asano, Marc, Ueda, Reid, & Nepal, Shaili. Network Reduction Algorithm for Developing Distribution Feeders for Real-Time Simulators: Preprint. United States.
Nagarajan, Adarsh, Nelson, Austin, Prabakar, Kumaraguru, Hoke, Andy, Asano, Marc, Ueda, Reid, and Nepal, Shaili. Thu . "Network Reduction Algorithm for Developing Distribution Feeders for Real-Time Simulators: Preprint". United States. doi:. https://www.osti.gov/servlets/purl/1364143.
@article{osti_1364143,
title = {Network Reduction Algorithm for Developing Distribution Feeders for Real-Time Simulators: Preprint},
author = {Nagarajan, Adarsh and Nelson, Austin and Prabakar, Kumaraguru and Hoke, Andy and Asano, Marc and Ueda, Reid and Nepal, Shaili},
abstractNote = {As advanced grid-support functions (AGF) become more widely used in grid-connected photovoltaic (PV) inverters, utilities are increasingly interested in their impacts when implemented in the field. These effects can be understood by modeling feeders in real-time systems and testing PV inverters using power hardware-in-the-loop (PHIL) techniques. This paper presents a novel feeder model reduction algorithm using a Monte Carlo method that enables large feeders to be solved and operated on real-time computing platforms. Two Hawaiian Electric feeder models in Synergi Electric's load flow software were converted to reduced order models in OpenDSS, and subsequently implemented in the OPAL-RT real-time digital testing platform. Smart PV inverters were added to the real-time model with AGF responses modeled after characterizing commercially available hardware inverters. Finally, hardware inverters were tested in conjunction with the real-time model using PHIL techniques so that the effects of AGFs on the choice feeders could be analyzed.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jun 15 00:00:00 EDT 2017},
month = {Thu Jun 15 00:00:00 EDT 2017}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share:
  • Real-time applications demand fast computation, this paper proposes an efficient algorithm for real-time network reconfiguration on large unbalanced distribution networks. A novel formulation of the network reconfiguration to achieve loss minimization and load balancing is given. To reduce computational requirements for the solution algorithm, well justified power flow and loss reduction formulas in terms of the on/off status of network switches are proposed for efficient system updating. The algorithm relies only a few full power flow studies based on system states attained by explicit expressions using backward-forward sweeps for efficient computation of system`s states at the critical system operating points.more » The solution algorithm runs in an amount of time linearly proportional to the number of tie switches and the number of sectionalizing switches in the system. The solution algorithm has been implemented into a software package and tested on unbalanced distribution systems including a system with 292-buses, 76-laterals, 7 transformers, 45 switches and 255 lines sections under diverse system conditions.« less
  • This paper identifies the data requirements for real-time monitoring and control of distribution systems. It points out that in addition to having supervisory control and data acquisition on switches and control equipment, methods are needed to obtain an accurate estimation of data needed for feeder automation functions. A meter placement method is proposed for this purpose. It is shown that the measurements from such a metering scheme can be used with a state estimator to provide the real-time data needed for real-time monitoring of distribution system.
  • The work developed here proposes a methodology for calculating switching angles for varying DC sources in a multilevel cascaded H-bridges converter. In this approach the required fundamental is achieved, the lower harmonics are minimized, and the system can be implemented in real time with low memory requirements. Genetic algorithm (GA) is the stochastic search method to find the solution for the set of equations where the input voltages are the known variables and the switching angles are the unknown variables. With the dataset generated by GA, an artificial neural network (ANN) is trained to store the solutions without excessive memorymore » storage requirements. This trained ANN then senses the voltage of each cell and produces the switching angles in order to regulate the fundamental at 120 V and eliminate or minimize the low order harmonics while operating in real time.« less
  • In order to support the ongoing Maui Smart Grid demonstration project advanced metering has been deployed at the distribution transformer level in Maui Electric Company's Kihei Circuit on the Island of Maui. This equipment has been custom designed to provide accurately time-stamped Phasor and Power Quality data in real time. Additionally, irradiance sensors have been deployed at a few selected locations in proximity to photovoltaic (PV) installations. The received data is being used for validation of existing system models and for impact studies of future system hardware. Descriptions of the hardware and its installation, and some preliminary metering results aremore » presented. Real-time circuit visualization applications for the data are also under development.« less