Abstract:
Currently, the PV power generation is rapidly expanding worldwide; therefore, the PV power plants have been installed widely including in Thailand. To install the PV power plants, there are two designed systems used 1) the central inverters and 2) the string inverters. This thesis presented the comparison analysis of PV power plants performance between central inverters and string inverters with the installed capacity higher than 1 MW.
The thesis aimed to analyze and compare the central inverters and string inverters installed at the PV power plants in Thailand. The observed 4 PV power plants using central inverters were Ubonratchathani project, Ayutthaya (1) project, Ayutthaya (2) project, and Lopburi (6) project, while the observed 4 PV power plants using the string inverter installed in Phetchaburi province were BSP FOUR project, BSP FIVE project, BSP SEVEN (1) project, and BSP SEVEN (2) project. All monitored data of the PV power plants and solar radiation of central inverters and string inverters were collected from January to December 2017.
The results revealed that the performance value of PV power plants using the central inverters were Ubonratchathani project 81.17%, Ayutthaya (1) project 76.10%, Ayutthaya (2) project 77.08%, and Lopburi (6) project 77.49%. The performance value of 4 PV power plants using string inverters were BSP FOUR project 83.43%, BSP FIVE project 83.61%, BSP SEVEN (1) project 82.62%, and BSP SEVEN (2) project 85.11%. The data analysis showed that the performance value of PV power plants using string inverters was higher than the performance value of PV power plants using central inverters at the average of 5.72%.