TY - JFULL AU - Ali M. Eltamaly and A. I. Alolah and R. Hamouda and M. Y. Abdulghany PY - 2009/7/ TI - A Novel Digital Implementation of AC Voltage Controller for Speed Control of Induction Motor T2 - International Journal of Mechanical and Mechatronics Engineering SP - 677 EP - 683 VL - 3 SN - 1307-6892 UR - https://publications.waset.org/pdf/13788 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 30, 2009 N2 - In this paper a novel, simple and reliable digital firing scheme has been implemented for speed control of three-phase induction motor using ac voltage controller. The system consists of three-phase supply connected to the three-phase induction motor via three triacs and its control circuit. The ac voltage controller has three modes of operation depending on the shape of supply current. The performance of the induction motor differs in each mode where the speed is directly proportional with firing angle in two modes and inversely in the third one. So, the control system has to detect the current mode of operation to choose the correct firing angle of triacs. Three sensors are used to feed the line currents to control system to detect the mode of operation. The control strategy is implemented using a low cost Xilinx Spartan-3E field programmable gate array (FPGA) device. Three PI-controllers are designed on FPGA to control the system in the three-modes. Simulation of the system is carried out using PSIM computer program. The simulation results show stable operation for different loading conditions especially in mode 2/3. The simulation results have been compared with the experimental results from laboratory prototype. ER -