Electric Power Quality Monitoring and Control of the SoE Clean Room

摘要

The senior design team was presented with a challenge of addressing power quality issues in the School of Engineering’s clean room. Discussion with the faculty involved in the operation of the room indicated that some power quality issues such as periodic outages and brownouts posed serious potential damage to computer equipment, and solving these issues would save the university money and lost time. The senior design team used Eagle Power Quality Meters to monitor and record voltage waveforms on multiple 120V AC phases for three months and also collected real-time data of current and consumed power from the room. Based on the collected data, the team did power quality analysis, recognized some single phase contingency conditions, and determined that isolation via a large battery backed UPS inverter would be most ideal. The biggest constraint of the design was cost. UPS inverters designed to carry a high power load such as the clean room, are highly expensive to design and build. This was countered by producing a low cost, demonstration platform that the school can use to justify expenditure to upgrade. A literature research of IEEE papers as well as observations of residential grade inverters is performed to design the circuit, and the microcontroller logic as developed by the team as an ideal, low cost control solution. The team has designed the inverter topology, programmed the logic controller, and designed a load center to test the inverter’s capabilities. However, cleaning of the fundamental frequency can still be addressed. This would require an altered topology to allow additional transistors in each phase’s network, as well as a reprogrammed microprocessor to take advantage of the change in topology. This project will not only rationalize current power quality issues faced by the SoE clean room, but it can also be used in residential applications to drive three phase equipment.