PERFORMANCE INVESTIGATION OF MATRIX 61 CONVERTER FED INDUCTION MOTOR DRIVE

Abstract

Researchers have always been improving the technology when it comes to AC to AC power conversion. Matrix converter is a 3x3 array of 9 bi-directional semiconductor switches that connects directly the three phase source to the three phase load without using any DC-link or large energy storing element. This converter has several advantages over conventional methods such as sinusoidal input and output currents, operation at unity power factor, regeneration capability, low volume and lack of bulky reactive elements. The matrix converter requires a bidirectional switch capable of blocking voltage and conducting current in both directions. Unfortunately, there are no such devices currently available, so diode bridge bidirectional switch is realized using diodes and MosFet. This thesis concerns the development of three phase matrix converter to attain output AC voltage of varying frequency. The modulation algorithms used for the matrix converter are described. The firing pulses for the switching devices are generated by FPGA which is an ISE Xilinx product. Venturini modulation strategy is implemented on FPGA. Closed loop control of the matrix converter fed induction motor drive has been demonstrated. A controller has been designed to achieve closed-loop speed control of the drive system, employing indirect vector control technique. The simulation results under various operating conditions have verified the correct operation of system. The results demonstrated the steady-state and transient performance as well as the regenerative operation of the drive system. The matrix converter is a good alternative to an inverter drive for three phase frequency control