Vector Control System of Self-Excited Induction Generator Including Iron Losses

Abstract

In this doctoral dissertation, a new dynamic model of an asynchronous machine with iron losses included is proposed. Within the proposed model, iron losses are represented by an equivalent resistance whose value depends on the stator frequency and the magnetic flux in the air gap. The proposed model was first applied at the simulation level to analyze the operation of an unregulated self-excited asynchronous generator. The validity of the simulation model was confirmed based on comparison with experimental results. The proposed model was then used to develop a new vector control system. Within the developed system, the calculation of the equivalent resistance of iron losses and inter-inductance is performed in real time using the corresponding characteristics, which were previously determined as part of the no-load test. Testing of the developed vector control system was performed at the simulation and experimental levels. After the validity of the proposed approach was confirmed, two new algorithms were developed to optimize the efficiency of the control system. The algorithms were tested at both simulation and experimental levels and a significant increase in system efficiency was found due to the application of the algorithms. In addition, the calculated amount of total control system losses was corrected for the estimated losses of the routers in the system.

Mateo Bašić

Full Professor | Department of Power Electronics and Control

Full professor at the Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture in Split, with recent research interests related to the fields of power electronics and renewable energy sources, with a special focus on energy-efficient control of inverters, battery systems, wind turbines, photovoltaic sources and self-excited induction generators in microgrids - both in island operation and in grid-tie operation.