High performance DC motor drive using a PWM rectifier with power transistors

This work presents a new rectifier connected in the bridge configuration, which uses six bidirectional switches to connect the 3-phase source to the load. Each bidirectional switch comprises two power MOSFET transistors working in the switching mode. A simple pulse-width modulation strategy is developed using the ficticious source concept. The convertor works at a high switching frequency and for this reason it does not need large storage elements. In addition, the simple control strategy and the high controllability of the power elements produce a dramatic simplification of the control and logic circuits. The convertor accepts regenerative power and for this reason it is well suited for use in the 4-quadrant speed control of DC machines. The performance of the convertor was experimentally investigated in the speed control of a 0.6 kW DC servomotor.