Engineering Commons^™

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 …

Electric Smart Load Meter, Johnny Tran

Electrical Engineering

This project details the design of an electric meter that reads the signals of any device plugged into an outlet and displays cost readings that may potentially reduce power consumption. The sensor monitors whether a plugged in device continuously consumes power after completely charging up. For a charging device, the current remains constant until the device reaches 100% charge. Once the device becomes fully charged, the current discontinues for proper power usage. A unique aspect of the meter is that it displays cost per hour, day, and year. Displaying the cost per unit of time creates awareness for customers, potentially …

Designing A Power Distribution System For The Arce 257 Revit Structural Model, Reid Wilhelm

Electrical Engineering

The construction industry needs engineers. Mechanical, electrical, and plumbing engineers, better known as MEPs, comprise a large number of employees who design and assist in the building of commercial structures. In particular, electrical engineers design power distribution systems for these buildings, including the power, lighting, low voltage, and fire protection subsystems.

Here at Cal Poly, architectural engineers enrolled in ARCE 257 create authentic structural plans for a fictitious two-story structure. This senior project transforms these structural plans into an architectural model and creates a power distribution system for the entire building. This is done through a building information modeling (BIM) …

Solar Generation's Impact On Fault Current, Kody Heppner

Electrical Engineering

California is paving the road for other states with the capacity of solar installations for residential and commercial entities. The added capacity of solar generation to the state's electric grid has an impact on power flow and fault currents. This project looks at the impact of solar installations on fault currents. Feeders with added residential rooftop solar and larger commercial solar installations may impact the system differently than a large, utility-sized solar installation. This project looks at the impact of both cases on the magnitude of fault current during many different fault types and locations that can occur within a …

Energy Harvesting From Exercise Machines Buck-Boost Dc Dc Converter With The Lt8705 Controller, Ryan Matteo

Electrical Engineering

In order to increase sustainability and save money, the Energy Harvesting from Exercise Machines (EHFEM) system uses human supplied energy to self-power exercise equipment such as spin bikes, elliptical trainers, ergometers, etc. This document covers the design and implementation of a Buck-Boost DC-DC converter using the LT8705 controller into the EHFEM system. This project improves upon the overall efficiency of the Buck-Boost Converter designed by past groups working on the EHFEM system.

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. …

Automatic Water Pump Controller, Alam D. Salguero, Kyle Russell Marquez Weeks

Electrical Engineering

In countries including Indonesia, Mexico, Guatemala, and El Salvador, a city water authority supplies the clean water and pumps it into large ground-level storage tanks. A resident’s water pump then pumps the water to a water tank on top of his/her house. When the water level in the ground-level storage tank becomes too low, the pump siphons air and shuts down, requiring a resident to manually prime the water pump to get it running again. Residents struggle to monitor the water level of the tanks effectively and keep the pump running properly. To remedy the issue, the Automatic Water Pump …

Micro-Inverter Improvement For The Energy Harvesting From Exercise Machine Project, James Ralston

Electrical Engineering

The Energy Harvesting from Exercise Machines (EHFEM) project at California Polytechnic State University consists of several different projects coming together to add human generated power to the grid. This project focuses on implementing a more efficient micro-inverter. The micro-inverter used to convert DC to AC voltage requires up to 5 minutes before the conversion process begins. This time lag significantly diminishes the power produced from an exercising individual. Research of micro-inverters approved by the CEC introduces desirable micro-inverters, available for use in California, to the EHFEM project. Testing the two most desirable micro-inverters found from research allows for quantifying of …

Rf Power Harvesting Rectenna, Jimmy Tang, Raymond Phu, Tom Geranios, Benjamin Muñoz

Electrical Engineering

Sustainability is one of today's primary engineering objectives. This principle involves system design that minimizes environmentally harmful energy emissions and resource consumption, and maximizes renewable energy practices [1]. Communication antennas transmit wireless signals that can be converted into usable energy. The Rectenna system described in this report, shown in Figure 1, was designed to accomplish this energy conversion, with -5dBm (316µW) minimum power at the rectifier input. Since typical ambient signal power is in the -70dBm (0.1nW) range, the proposed system could only convert passive, relatively high-power microwave band AC signals to DC. The Rectenna system was designed for 1.9GHz …

Solar-Powered Hot Tub, Jonathan Peterson, Anthony Zepeda

Electrical Engineering

This paper discusses the design and implementation of a solar-powered hot tub. The concept of this project was to design an independently-operated hot tub powered by a 12V rechargeable battery, charged during the day by a single 400W solar panel. For this purpose, a twenty-year-old name-brand hot tub was purchased, in used condition. The plumbing, AC electrical wiring, and mechanical pumps were all removed and replaced with new components to meet our design specifications. Additionally, a solar water-heater was designed and integrated into the system to directly apply the sun’s heat to water pumped in and out of the tub, …

Faraday Rechargeable Battery System, Alex Gasper, Bret Omsberg

Electrical Engineering

The modern electronic age has given birth to a variety of innovative and hand-held devices that are carried with the consumer nearly 24 hours a day, seven days a week. The one shortfall of these devices is their energy storage, or in most cases, a battery. The Faraday Rechargeable Battery System is a unique system that will generate electricity through rotational movement of a tire. This can be a bike, a car, or any other transportation vehicle that uses wheels for movement. The kinetic energy that is engendered either by the user or an engine can then be converted into …