Engineering Commons^™

Protection Of Microgrids: A Scalable And Topology Agnostic Scheme With Self-Healing Dynamic Reconfiguration, Phani Harsha Gadde

All Dissertations

Momentum towards realizing the smart grid will continue to result in high penetration of renewable fed Distributed Energy Resources (DERs) in the Electric Power System (EPS). These DERs will most likely be Inverter Based Resources(IBRs) and will be an integral part of the distribution system in the near future. The drive towards resiliency with these IBRs will enable a modular topology where several microgrids are tied together, operating synchronously to form the future EPS at the distribution level.

Since the microgrids can evolve from existing distribution feeders, they will be unbalanced in load, phases, and feeder impedances. A typical control …

Power Line Coupling Power Supply Design, Janine Gian Christii C. Darato, Jeni K. Kawate, Nicholas A. Marta

Electrical Engineering

In this project, a power supply was designed for a startup company, Perch Sensing, to detect wildfires with the use of distributed sensors across power lines. The purpose of the power supply is to provide 15W of power to a microcontroller, which controls the sensor nodes. The power supply hangs from power lines and draws energy by inductively coupling to these lines. Our design starts with a current transformer that steps down the current from the power line, which is fed into a shunting mechanism as a safety precaution when the load is absent, then to the power supply itself. …

Cal Poly Ee 518 Electric Power Protection Laboratory, Richard Terre, Vincent Tham, Austin Kurth

Electrical Engineering

Facing a rapidly-changing power industry, the electrical engineering department at Cal Poly San Luis Obispo proposed Advanced Power Systems Initiatives to better prepare its students for entering the power industry. These initiatives call for the creation of a new laboratory curriculum that utilizes microprocessor-based relays to reinforce the fundamental concepts of power system protection.

The electric power protection laboratory (EPPL) senior project is the validation of lab manuals written for the planned EE-518 power system protections laboratory looking to be offered in Spring 2020 alongside the current lecture class under the same designation. This report evaluates the lab manual, verifies …

Microgrid Protection Student Laboratory, Ian Hellman-Wylie, Joey Navarro

Electrical Engineering

To better prepare students for careers in the electric power industry, specifically in the discipline of power system protection, the Electrical Engineering Department at Cal Poly San Luis Obispo proposed an initiative calling for the creation of new laboratory curriculum that uses microprocessor-based relays to give students hands-on experience in the application of protection theory. This report describes the creation of a system that meets this need by providing a laboratory-scale power system that demonstrates the use of common protective relays and protection schemes. This system provides a platform for laboratory coursework using protective relays for transmission line, transformer, and …

Power Distribution:Protection Analysis, Avneet S. Samra

Electrical Engineering

The objective of this project is to build a radial distribution system that operates on a lower voltage. The system consists of a transmission line protected by a SEL-351 Relay, a three- phase transformer protected by a SEL-587 Relay, and a three-phase induction motor protected by a Cooper Form 6 Controller. The SEL-351, SEL-587, and the Cooper Form 6 Controller are microprocessor-based relays that are used to provide protection under faulted conditions. When a fault is detected in the system, the closest upstream relay sends a trip signal to its assigned local breaker. The SEL-351 provides overcurrent protection for the …

Transformer And Motor Protection Scheme, Bijan Vakilifathi

Electrical Engineering

No abstract provided.

Integration Of Sel Relays To Provide Motor, Transmission Line, And Transformer Protection, Christopher Ewing, Bryce Keefer

Electrical Engineering

The objective of this project is to familiarize the performers with the principles of operation of the Schweitzer Engineering Laboratories (SEL) protective relays in both normal and fault conditions. The SEL-587, SEL-311L and SEL-710 microprocessor-based relays are used to provide protection for a system composed of transformers, simulated transmission lines and a 3-phase induction motor. Each of these relays provides protection by sending a trip signal to local breakers upon sensing a fault condition. The SEL-587 provides overcurrent and differential protection for a 3-phase transformer, while the SEL-311L provides differential and distance protection for a transmission line, and negative sequence. …

Power Protection Analysis For A Ten Bus System, Sean Hanna

Electrical Engineering

Each power system built in the industry requires a protection plan. Undetected faults in a power system can contribute to hazardous conditions, overheating of power devices, low or high system voltages, unbalanced conditions, and blackouts. This senior project is the design of a protection plan for a power system using the software Electric Transient Analyzer Program (ETAP). With ten buses, five transformers, two generators, two motors, and six transmission lines, there are many possibilities for a fault to occur. The Load flow and fault analysis are studied before the system is protected. All components of the system are protected using …

Real Time Testing And Validation Of A Novel Short Circuit Current (Scc) Controller For A Photovoltaic Inverter, Vishwajitsinh H. Atodaria

Electronic Thesis and Dissertation Repository

About 45% applications from PV solar farm developers seeking connections to the distribution grids in Ontario were denied in 2011-13 as the short circuit current (SCC) capacity of several distribution substations had already been reached. PV solar system inverters typically contribute 1.2 p.u. to 1.8 p.u. fault current which was not considered acceptable by utility companies due to the need for very expensive protective breaker upgrades. Since then, this cause has become a major impediment in the growth of PV based renewable systems in Ontario.

A novel predictive technique has been patented in our research group for management of short …

Current Protection For The Energy Harvesting From Exercise Machines (Ehfem) Project, Colton Crivelli

Electrical Engineering

The Energy Harvesting from Exercise Machines (EHFEM) project intends to create an exercise machine that recycles the energy expended by an athlete operating the machine by sending it to the electric grid. The work done by the user goes through a DC-DC converter and an inverter in order to prepare it for delivery to the grid. A protection circuit ensures that the inverter does not try to pull too much current from the DC-DC converter. The project implements a current protection system that ensures the system doesn’t experience an overcurrent condition.

Sel-311l Overreaching Impedance Pilot Protection Laboratory, Brandon Van Loon

Electrical Engineering

The objective of this senior project is to protect a three terminal transmission line during fault conditions using the SEL-311L microprocessor based relay and communication assisted permissive over-reaching transfer trip protection (POTT). The SEL-311L’s directional distance elements are programmed to trip on internal faults while faults external to the zones of protection are ignored. Upon sensing a fault condition, the relay issues a trip command to the local breaker and a permissive key for tripping to the remote relay via fiber optic communication. When a permissive key is received and all other permissive conditions have been satisfied, the remote relay …

Hardware-In-Loop Evaluation Of Microgrid Protection Schemes, Kevin Michael Dowling

Masters Theses

Distributed energy resources are becoming more common in distribution systems. Higher energy prices and increased interest in alternative energy sources are two of the driving forces behind this trend. Local utilities, however, anticipate very serious distribution system protection problems resulting from high penetration of these resources.

The microgrid concept has been proposed as a possible solution to integrating distributed energy resources without adversely impacting the distribution system. Protection schemes have been proposed to work within this microgrid structure, but very little testing with real hardware is available. Without a practical solution for microgrid protection, backed by extensive studies, microgrids are …

Investigation Of Protection Issues And Method For The Distribution System With Distributed Generations, Ke Xu

Theses and Dissertations--Electrical and Computer Engineering

Because DGs are introduced into distribution systems, the coordination of fuses and reclosers doesn’t work well. It means the original protection schemes are not available for the distribution systems with DGs. This thesis paper presents the study on the impacts of DGs on the fault current and voltage in the distribution system by the simulation of a model distribution system. After we study the impacts of DG on distribution systems, there is an introduction of current several current protection schemes and fault locations methods. At last, an adaptive protection scheme with a more efficient fault location method for the distribution …

Motor Protection Lab Experiment Using Sel-710, Ozro Corulli

Electrical Engineering

Advancements in microprocessor based relay technology for power protection applications provide quicker response times and new methods of mitigation. This project develops a lab experiment for Cal Poly class EE444 - Power Systems Laboratory based on the Schweitzer SEL-710 motor protection relay. Learning objectives for this lab include relay setup, programming, and protection schemes for the following conditions: undervoltage, loss of phase, fault, locked rotor, and thermal overload. Today, utility companies across the globe use SEL relays for primary system protection, putting engineers familiar with their operation in high demand.

Dc-Dc Converter Input Protection System For The Energy Harvesting From Exercise Machines (Ehfem) Project, Ryan Turner, Zack Weiler

Electrical Engineering

The ongoing Energy Harvesting from Exercise Machines (EHFEM) project at Cal Poly San Luis Obispo seeks to provide renewable energy without the high cost of implementation by harvesting DC power generated on machines used for physical exercise. The EHFEM project consists of numerous subprojects that involve converting different types of exercise machines for power generation. This project specifically works by scaling the output voltage from an elliptical machine using a DC-DC converter and sending it through an Enphase Micro-inverter to feed AC power back to the power grid and minimize energy spending. As a subset of the much larger project, …

A Study Into The Use Of Microprocessor Relays For Motor Operated Valve (Mov) Electrical Protection In Nuclear Power Plants, James Andrew Tuccillo

Master's Theses

Motor Operated Valves (MOVs) are electro-mechanical components used to isolate, divert, or introduce fluid flow. The use of microprocessor relays for actuator motor electrical protection within nuclear power plants is the focus of this thesis and is implemented by providing a new and enhanced protection scheme that provides the adequate conservatism necessary to ensure valve operation while still maintaining electrical safety and continued operational availability. The comprehensive protection scheme is designed around an advanced microprocessor relay that has the ability to simulate the thermal overload conditions of a motor operating into a destructive thermal region. Through laboratory testing, the validity …