Sensorless Controller of Permanent Magnet Linear Generator For Wave Energy Systems

Abstract

In this paper structure and control method used in the power converter device for a low-speed permanent magnet linear generator (PMLG) is described. PMLG are widely used in wave energy converters, because they can be used with simple direct drive wave power take-off devices. One of main disadvantages of PMLG is high inner inductance, thus, PMLG has low output power without matching devices. Proposed control system utilizes physical parameters of PMLG to calculate its electromotive force (EMF) without EMF sensor. The method for the calculation of the main parameters of the control system and power conversion unit is presented. In order to proof the performance of proposed control method the simulation of the single-phase power electronic converter is carried on. The simulation results show that the proposed solution allowing to extract about 75% of the theoretical maximum power from the generator.