Stability analysis and experimental evaluation of a matrix converter drive system

The interest in using the matrix converter (MC) technology for motor drive applications is steadily increasing due to its advantages: high quality of the input currents, regeneration capability and high power density but a few unsolved issues delays its industrial use. This paper deals with one of them: the stability of a MC drive caused by using the voltage across the input filter capacitor in the control scheme. First, a small-signal model of the matrix converter is carried out for two load types: a passive RL-load and an induction motor, which is helping to assess the stability of the whole system. Based on this model, the factors that influence the stability are analyzed and design guidelines to improve the system stability are given and verified by simulations. Experimental results are carried out on an 8.5 kVA MC prototype, which show some disagreements with the theory but reasons for these are identified.