A Remote Area Power Supply (RAPS) Training Facility utilising SMA Sunny Island Inverter technology and National Instruments measurement package

摘要

RAPS systems can sometimes be a cheaper alternative for supplying power than connection to a distant utility. Most assuredly it is a cleaner method of producing electricity than coal or gas constituents, provided the diesel generator is used minimally. A modern RAPS system will generally have several sources of generation, typically they might be; solar, wind and a diesel/petrol generator coupled with a battery to store excess power. The RAPS 2 system at Murdoch University was selected for an overhaul early in 2010. The system was redesigned to include new inverter technology from SMA. The new system relies on 3 separate inverters to convert the sources directly into grid quality electricity, as opposed to some traditional RAPS systems that would have most of its elements feed a DC bus that connected to a single inverter. This novel way of setting up a mini grid finds its niche in situations when the terrain or meteorological conditions make it impractical to have generation equipment all localised and a DC bus would have higher associated cable losses. ududFor such a system to be of educational benefit to tertiary students, the variables within the system must be able to be monitored. To this end an advanced measurement system has been designed and procured so that every measurable point in the upgraded system is available for display. ududThe measurement system was designed using National Instruments compact DAQ (data acquisition) hardware, one of the first of its type to be introduced to the university. The compact DAQ unit has been coupled with isolation equipment supplied by Dataforth, which already has an existing prevalence throughout the engineering department. The subsequent measurement program monitors 31 system variables at a high sampling rate to provide real time information on the state of the system. The measurement program also monitors relevant meteorological aspects such as the solar irradiance and local wind speed. udThis report documents and details the steps taken to set up a new and novel RAPS system. Discussed are the approaches taken throughout the semester to project manage and facilitate progress. A detailed description is also given of the measurement and protection system that has been designed to allow students and the general public to get a good grasp on the performance of the system.