M.Sc. Tezi Görüntüleme
In this study, the effect of the closing angle on starting moments and dynamic behavior of the induction machine fed by three phase system is investigated.
As the switching elements of the machine with direct started or controlled systems has mechanical contacts, the closing angle of every phase can be different due to disorder or any reason, phase voltages are applied in different angle for the faulty contact.
Therefore, a power circuit, which closes every phase to be independent in different angles, with PIC 16F877A microcontroller having manual inputs, is implemented. Highspeed diodes with bridge connection, which gives permission for current passing with two directions in the power circuit, and IGBT are used. There is also TLP2200- IGBT and MOSFET driver as insulation and driver circuit in microcontroller output.
Mathematical model of the system is formed in VISSIM software, and the effect of different closing angles on dynamic behavior of induction machine is investigated with computer simulations. Experimental results are obtained with performed switching circuit with microcontroller and supported with simulation results.
In the simulation and experimental study, the optimum closing angles which form the lowest moment response in opposite direction and soft starting are determined.
Key words:Closing angle, Induction Machine, PIC 16F877A, Microcontroller