Digital real-time simulation of a four-quadrant DC drive for static transfer switch testing

This paper presents a digital real-time simulation of a four-quadrant DC motor drive used in a manufacturing plant subjected to operation of a solid-state transfer switch. The objective of the simulation is to allow laboratory evaluation of the performance of a DC drive controller under realistic operating conditions. A real-time model of an industrial 200-hp DC drive including a 12-thyristor reversible converter and a DC motor has been developed to run on a parallel processor system. The model has been first developed and tested offline using the Simulink Power System Blockset. Real-time parallel code is then generated and distributed to six DEC Alpha processors operating at 300 MHz. The simulator was designed in order to allow interfacing of actual controllers of motor drives and solid-state power transfer switch. Experimental results including real-time simulation waveforms illustrating the operation of DC drive and transfer switch are presented to demonstrate the feasibility and the usefulness of such a simulator in closed loop testing of industrial controllers