© The Institution of Engineers, Sri Lanka ENGINEER Developing a Test Bench to Test Grid Tie Inverters

Abstract: The need of electricity through-out the world is growing day by day at a considerable rate. The electricity demand of its consumers has already exceeded the supply. Hence, switching towards green energy is a must to remove this imbalance conditions between the electricity supply and demand. At this particular point, there is a higher tendency of the electricity consumers for moving towards domestic solar power. The grid tie inverters are the main building. So, the proper operation of an inverter is highly important. Although there exists an already provided data sheet by the manufactures along with the inverters, sometimes we can identify mal-operation conditions of these inverters irrespective of the data sheet provided and therefore, many complaints are aroused by the solar consumers. The issue is that there does not exist proper equipment to engage with all types of inverter testing schemes that had been listed in the IEEE 1547 standard; which is the relevant safety standard for interconnecting distributed resources with electric power systems. So, a test bench to test the grid tie inverters was developed according to IEEE 1547 standard. Tests that are stated in the standard were conducted with a higher accuracy data acquisition system and the relevant results were analyzed to determine whether a particular inverter operates within the limits at abnormal situations as described in the standard. Finally, a test report was generated to provide the solar power consumer informing the operation status of the inverter. This paper elucidates relevant inverter tests, the proposed methodologies to conduct the tests, the logic behind those tests for analysing purposes and the test results obtained for the calculations of the necessary test parameters, thus, the entire outcome will be highly important for the industry