Voltage compensator based on a direct matrix converter without energy storage

The objective of this study is to present a voltage compensator based on a matrix converter without energy storage, which can cope with common power quality problems presented in power distribution systems. The proposed scheme acquires from the grid the necessary energy during the disturbance, which eliminates the drawbacks imposed by the use of a dc-link and the need of energy storage components. A matrix converter study under unbalanced input voltage conditions is exposed, as well as a detailed explanation of the proposed modified direct space vector modulation (MDSVM). It has been verified that even when the supply voltage exhibits unbalanced conditions and harmonic distortion, the control strategy does not exhibit difficulties to synthesise the compensation voltages, provided the restrictions imposed by the formulation are fulfilled. Numerical simulations and experimental results from a laboratory scale prototype are presented to validate the performance of the compensator.