PhD Thesis Defence: Elena Santasheva, "Quasi-Z-Source Based String Inverter for Residential Photovoltaic Application"
- Place: NRG-422
27.06.2019, 11:00 AM
Elena Santasheva, "Quasi-Z-Source Based String Inverter for Residential Photovoltaic Application"
- Dr. Oleksandr Husev, Department of Electrical Power Engineering and Mechatronics, Tallinn University of Technology, Estonia
- Prof. Enrique Romero-Cadaval, School of Industrial Engineering, University of Extremadura, Spain
- Prof Ilya Galkin, Faculty of Power and Electrical Engineering, Riga Technical University, Latvia
- Prof Jose I. Leon, University of Sevilla, Spain
Nowadays the industrial Power Electronic Converters (PEC) for residential Photovoltaic (PV) application is based on the well-known DC-DC boost converter and DC-AC inverter. The solar PEC has the PV system in the input side, which leads to the following: the PEC should be able to regulate the input voltage in a wide range, provide Continuous Input Current (CIC) and have battery storage especially for residential application.
This work is dedicated to the novel concept of the PEC based on the impedance-source network. The PEC has benefited from quasi-Z-Source Network (qZSN) through such positive properties as shout-through immunity, CIC. To provide the required power to the grid the Battery Interface Converter (BIC) is proposed, which is able to provide the power even without the input source. To achieve the required quality of the grid current, the damped Proportional Resonant (dPR) controller with the harmonic compensation circuit are selected; to avoid the current spike during the start-up period, which may cause the current trigger protection, the optimization process of the dPR controller is proposed. To stabilize the dc-link voltage during the boost mode, the proportional integer derivative controller is used. To compensate the additional power losses caused by BIC, the active power decoupling approach realized by means of the specific control strategy of the BIC is proposed.
The theoretical results were confirmed by experimental results that were achieved by building up the solar inverter based on qZSN with a BIC prototype. The tests showed that the designed qZSI with BIC can be applied for residential PV application.