Distributed control of reactive power flow in a radial distribution circuit with high photovoltaic penetration

We show how distributed control of reactive power can serve to regulate voltage and minimize resistive losses in a distribution circuit that includes a significant level of photovoltaic (PV) generation. To demonstrate the technique, we consider a radial distribution circuit with a single branch consisting of sequentially-arranged residential-scale loads that consume both real and reactive power. In parallel, some loads also have PV generation capability. We postulate that the inverters associated with each PV system are also capable of limited reactive power generation or consumption, and we seek to find the optimal dispatch of each inverter's reactive power to both maintain the voltage within an acceptable range and minimize the resistive losses over the entire circuit. We assume the complex impedance of the distribution circuit links and the instantaneous load and PV generation at each load are known. We compare the results of the optimal dispatch with a suboptimal local scheme that does not require any communication. On our model distribution circuit, we illustrate the feasibility of high levels of PV penetration and a significant (20% or higher) reduction in losses.Comment: 6 pages, 5 figures

Integrating Low Voltage Distribution Systems to Distribution Automation

The aim of this thesis is to define and study the key elements and the main characteris-tics of the integration of the low voltage (LV) distribution systems to distribution auto-mation (DA). The key elements are defined by studying the development of essential systems in LV distribution networks as well as by studying the development of the net-works by way of evolution phases. The key elements and the main characteristics of the integration to DA are illustrated by a certain model of a LV distribution network under its development. For a start DA is reviewed by generally used functions and by technologies. The review includes the data and the information systems and in addition the communication net-works are studied generally. Thereafter the main elements of LV distribution networks are presented and their evolution visions are introduced. The main elements comprises of the distribution network, distributed generation, smart energy metering, electric vehicles and energy storages. The approach to the integration is the evolution of LV distribution networks, so four main evolution phases are introduced; traditional, boom of distributed generation, mi-crogrid and intelligent microgrid. The evolution phases bases on general research publi-cations and visions of Smart Grids. Management architectures for the networks are pre-sented. Also requirements for communication are evaluated by studying the number of nodes, capacity requirements for transferred data types and fault and event frequencies. In order to define a proposal for integrating LV distribution networks to DA, the man-agement architectures and the studied requirements are compared to produce functions for DA. As a result, the proposal is presented based on the studied architectures and re-quirements. In addition considerable issues are introduced relating to the functions in devices or sub-systems, which are needed for DA applications. This thesis indicates the need for further studies, such as: Which are the desired DA functions to be extended to LV distribution networks? Which device or system should offer the desired functions? How well the potential protocols using some media type serves the functions?fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

Open-Source, Open-Architecture SoftwarePlatform for Plug-InElectric Vehicle SmartCharging in California

This interdisciplinary eXtensible Building Operating System–Vehicles project focuses on controlling plug-in electric vehicle charging at residential and small commercial settings using a novel and flexible open-source, open-architecture charge communication and control platform. The platform provides smart charging functionalities and benefits to the utility, homes, and businesses.This project investigates four important areas of vehicle-grid integration research, integrating technical as well as social and behavioral dimensions: smart charging user needs assessment, advanced load control platform development and testing, smart charging impacts, benefits to the power grid, and smart charging ratepayer benefits

ANOMALY INFERENCE BASED ON HETEROGENEOUS DATA SOURCES IN AN ELECTRICAL DISTRIBUTION SYSTEM

Harnessing the heterogeneous data sets would improve system observability. While the current metering infrastructure in distribution network has been utilized for the operational purpose to tackle abnormal events, such as weather-related disturbance, the new normal we face today can be at a greater magnitude. Strengthening the inter-dependencies as well as incorporating new crowd-sourced information can enhance operational aspects such as system reconfigurability under extreme conditions. Such resilience is crucial to the recovery of any catastrophic events. In this dissertation, it is focused on the anomaly of potential foul play within an electrical distribution system, both primary and secondary networks as well as its potential to relate to other feeders from other utilities. The distributed generation has been part of the smart grid mission, the addition can be prone to electronic manipulation. This dissertation provides a comprehensive establishment in the emerging platform where the computing resources have been ubiquitous in the electrical distribution network. The topics covered in this thesis is wide-ranging where the anomaly inference includes load modeling and profile enhancement from other sources to infer of topological changes in the primary distribution network. While metering infrastructure has been the technological deployment to enable remote-controlled capability on the dis-connectors, this scholarly contribution represents the critical knowledge of new paradigm to address security-related issues, such as, irregularity (tampering by individuals) as well as potential malware (a large-scale form) that can massively manipulate the existing network control variables, resulting into large impact to the power grid

Data Driven Synthetic Load Modeling for Smart City Energy Management Studies

The primary aim of this dissertation is to provide synthetic residential load models with granular level information on the customers having information about the appliances that constitute each individual residential customer through time. The synthetic load model is capable of being widely utilized by the power system research community since only publicly available data is utilized for its generation. This gives researcher’s access to how the synthetic load was made and also how accurate the model is in representing real power system regions. As the title of the dissertation suggests, the synthetic residential load models are intended for smart city energy management studies. Smart city energy management studies have the ability to control tens of thousands of electricity customers in a coordinated manner to enact system-wide electric load changes. Such load changes have the potential to reduce congestion (i.e. stress on power system components) and peak demand (i.e. the need for peaking generation), among other benefits. For smart city energy management studies to have the capability of evaluating how their strategies would impact the actual power system, datasets that accurately characterize the system load are required that also contain individual loads of all buildings in a given area. Currently, such data is publicly unavailable due to privacy concerns. This dissertation’s synthetic residential load model combines a top down and bottom up approach for modeling individual residential customers and their individual electric assets, each possessing their own characteristics, using time-varying queueing models. The aggregation of all customer loads created by the queueing models represents a known city-sized load curve to be used in smart city energy management studies. The dissertation presents three queueing residential load models that make use of only publicly available data to alleviate privacy concerns. The proposed approach is mainly driven by the aggregated distribution companies load. An open-source Python tool to allow researchers to generate residential load data for their studies is also provided. The simulation results comparing the three queueing synthetic load models consider the ComEd region (utility company from Chicago, IL) to demonstrate the model’s characteristics, impact of the choice of model parameters, and scalability performance of the Python tool. The developed residential synthetic queueing load models are utilized to create the Midwest 240-Node distribution test case system, which generates appliance-level synthetic residential load for 1,120 homes for the Iowa State distribution system test case with 193 load nodes over three feeders. The Midwest 240-Node is a real distribution system from the Midwest region of the U.S. with real one-year smart meter data at the hourly aggregated node level resolution for 2017 available in an OpenDSS model. The synthetic residential queueing load model generated for the Midwest 240-Node one-year date has a mean absolute percentage error of 2.5828% in relation to the real smart meter data. The Midwest 240-Node distribution system OpenDSS model was converted to GridLAB-D to enable smart grid and transactive energy studies. The percentage of maximum error observed on voltage magnitude from the OpenDSS to GridLAB-D model is below 0.0009%. The GridLAB-D model and the generated synthetic residential load is made publicly available. The Midwest 240-Node real distribution system with the synthetic residential load that follows the real data from smart meters is intended to be a distributed energy active consumer test system network. The focus of the developed synthetic residential load models is smart city energy management studies; however, they can be utilized in many power systems studies to evaluate economic and technical impacts of distributed energy resources. For example, this dissertation also presents the utilization of the synthetic models for a PV rich low voltage network. The main component of the smart grid is demand response. Demand response, or energy management, utilizes commonly passive load in to active power system resources. Residential demand response, when aggregated, is capable of performing system-wide changes that enable its participation in the power system markets. This dissertation developed residential synthetic models to enable the standardization of approaches and allow different approaches to be compared under the same environment

Distributed resource integration analysis and network design of electric power distribution systems

The integration of high percentages of distributed energy resources and controllable loads into the distribution system coupled with the strict power quality and service reliability requirements at the power distribution level are necessitating a significant change in the planning, operation and control of the traditional power distribution system. The future power distribution circuits should be able to accommodate the new technologies while simultaneously providing a desired level of power quality and service reliability to the customers. This thesis aims to address the current and future grid requirements of both existing as well as new distribution systems with regard to power quality and service reliability issues. Several methods are proposed to evaluate and mitigate power quality and service reliability concerns due to the integration of smart grid technologies into both existing and new distribution circuits. Notably, for the existing distribution circuits, integration studies are simulated to analyze and mitigate the impacts of electric vehicle loads and photovoltaic generation on the distribution voltages. Furthermore, the problem of siting, sizing and deployment of distributed energy storage systems in meeting distribution planning requirements with regard to integrating distributed generation and providing contingency requirements is also addressed. A new distribution system both grid-connected and operating in islanded mode, however, could be designed to the new requirements. The new distribution circuit could be designed to meet the power quality and service reliability standards directly, thus more efficiently mitigating the concerns. In the thesis, the new distribution circuit design is approached from the perspective of maximizing the service reliability. For the new distribution circuit, approaches to reliability based distribution circuit design are proposed.Electrical and Computer Engineerin

Hardware Prototype for a Multi Agent Grid Management System

There is great effort in the power industry to incorporate Smart Grid functionalities to existing power systems. Distributed generation and the hardware necessary to interface the existing grid, as well as control algorithms to efficiently couple and operate these systems are being researched and implemented extensively. However, the added complexity of such components results in greater opportunities for failure in a system which is already challenging to protect.;There is great effort in the power industry to incorporate Smart Grid functionalities to existing power systems. Distributed generation and the hardware necessary to interface the existing grid, as well as control algorithms to efficiently couple and operate these systems are being researched and implemented extensively. However, the added complexity of such components results in greater opportunities for failure in a system which is already challenging to protect.;There is great effort in the power industry to incorporate Smart Grid functionalities to existing power systems. Distributed generation and the hardware necessary to interface the existing grid, as well as control algorithms to efficiently couple and operate these systems are being researched and implemented extensively. However, the added complexity of such components results in greater opportunities for failure in a system which is already challenging to protect.;There is great effort in the power industry to incorporate Smart Grid functionalities to existing power systems. Distributed generation and the hardware necessary to interface the existing grid, as well as control algorithms to efficiently couple and operate these systems are being researched and implemented extensively. However, the added complexity of such components results in greater opportunities for failure in a system which is already challenging to protect