A fault ride through, power management and control method for grid integrated photovoltaic (PV) system with supercapacitor energy storage system (SCESS) is given in this paper. During normal operation the SCESS will be used to minimize the short term variation as it has high power density and during fault at the grid side it will be used to store the generated power from the PV array for later use and for fault ride through.
To capture the maximum available solar power, Incremental Conductance (IC) method is used for maximum power point tracking (MPPT). An independent P-Q control is realize to transfer the produce power to the grid using a Voltage source inverter (VSI). The SCESS is connected to the system using a bi-directional buck boost converter. The system model has been grown that consists of PV module.
buck converter for MPPT, buck-boost converter to connect the SCESS to the DC link. Three free controllers are realize for each power electronics block. The effectiveness of the planned controller is checked on Real Time Digital Simulator (RTDS) and the results verify the perfection of the planned approach.
- Active and reactive power control
- Fault ride through
- Photovoltaic system
- RTDS Supercapacitor
- Energy storage
Fig.1. Grid connected PV system with energy storage
EXPECTED SIMULATION RESULTS:
Fig.2. Grid voltage after three phase fault is applied
Fig.3. PV array power PPV with SCESS and with no energy storage
Fig.4. Grid active power Pg for a three phase fault with and without energy storage
Fig.5.SCESS power PSC for the applied fault on the grid side
Fig.6. Grid reactive power Qg during three phase fault
Fig.7. DC link voltage for the applied fault
Fig.8. PV array voltage VPV during three phase fault
Fig.9. MPPT output voltage Vref for the applied fault
This paper now grid connected PV system with supercapacitor energy storage system (SCESS) for fault ride through and to minimize the power variation. Incremental conductance based MPPT is realize to track the maximum power from the PV array.
The generated DC power is connected to the grid using a buck converter, VSI, buck-boost converter with SCESS. The SCESS which is connected to the DC link controls the DC link voltage by charging and discharging process. A P-Q controller is realize to transfer the DC link power to the grid.
During normal operation the SCESS minimizes the variattion caused by change in glow and temperature. During a grid fault the power produce from the PV array will be stored in the SCESS. The SCESS supplies both active and reactive power to ride through the fault. RTDS based results have shown the validity of the planned controller.
 T. Esram, P.L. Chapman, “Comparison of Photovoltaic Array Maximum Power Point Tracking Techniques,” IEEE Transaction on Energy Conversion, vol.22, no.2, pp.439-449, June 2007
 J. M. Enrique, E. Durán, M. Sidrach-de-Cardona, and J. M. Andújar,“Theoretical assessment of the maximum power point tracking efficiency of photovoltaic facilities with different converter topologies,” Sol. Energy, vol. 81, no. 1, pp. 31–38, Jan. 2007.
 W. Xiao, N. Ozog, and W. G. Dunford, “Topology study of photovoltaic interface for maximum power point tracking,” IEEE Trans. Ind. Electron., vol. 54, no. 3, pp. 1696–1704, Jun. 2007.
 J. L. Agorreta, L. Reinaldos, R. González, M. Borrega, J. Balda, and L. Marroyo, “Fuzzy switching technique applied to PWM boost converter operating in mixed conduction mode for PV systems,” IEEE Trans. Ind. Electron., vol. 56, no. 11, pp. 4363– 4373, Nov. 2009.
 A.Schneuwly, “Charge ahead [ultracapacitor technology and applications]”, IET Power Engineering Journal, vol.19, 34-37, 2005.