The number of photovoltaic (PV) generators has been significantly increased worldwide as a main renewable energy resource. The output power of PV generators mainly depends on the solar irradiance, module temperature, and field conditions. Therefore, the maintenance of the PV system is necessary to improve the reliability in its use. In this paper, a novel method to diagnose output power lowering in a PV array is proposed to keep the good performance of its output power based on the relationships between PV module temperature, current, and voltage under maximum power point conditions. In particular, the proposed method does not require the accurate information in specification on PV module and sensors for measuring irradiation levels, which are required in conventional monitoring systems. This results in the reduction of cost. Then, it is effectively applied to a practical PV system by using the Kalman-filter algorithm. The performances of the proposed diagnosis method are evaluated and verified with the laboratory experiment and field tests as well as the PSCAD/EMTDC-based simulation test.
Bibliographical noteFunding Information:
Manuscript received November 20, 2011; revised May 8, 2012 and July 26, 2012; accepted August 29, 2012. Date of publication September 19, 2012; date of current version November 16, 2012. This work was supported by the National Research Foundation of Korea Grant funded by the Ministry of Education, Science and Technology (MEST) (No. 2012-0008741). Paper no. TEC-00619-2011.
All Science Journal Classification (ASJC) codes
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering