[Show abstract][Hide abstract] ABSTRACT: A sensorless control strategy is proposed based on a novel topology for the rectification of the permanent magnetic synchronous generator (PMSG) in the wind generation system. Three one-phase power factor correction (PFC) circuits for each phase of PMSG, called three-phase PFC rectifier, are employed in this topology. Every stator current is controlled in phase with the corresponding electromotive force (EMF) of the PMSG. Based on the models of the PMSG and the PFC circuits, the EMF is reconstructed and the rotor flux linkage is observed. The phase angle for the current control is derived from the flux linkage using a phase locked loop (PLL). Results of both simulations and experiments verify that sinusoidal AC currents are in phase with the fundamental voltages of the EMFs of PMSG with the proposed sensorless control strategy.
[Show abstract][Hide abstract] ABSTRACT: For rectification of the three-phase AC voltages of permanent magnetic synchronous generator (PMSG) applied to variable speed constant frequency wind generation, a synchronous PI current control technique is proposed based on a novel topology called three-phase PFC rectifier. It consists of three single-phase power factor correction (PFC) circuits, each of which is for one phase of PMSG. The stator alternating currents, transformed to direct currents in the synchronously rotating reference frame, are controlled by PI regulators, and zero steady-state error of fundamental currents can be achieved and harmonics suppressed. Considering the specialties of the PFC circuit and the behavior of the PMSG, the current control is aimed to keep the stator phase current and voltage being in phase and the corresponding control structure is developed. Results of simulation and experiments on a 1kW prototype platform verify that the steady DC output voltage and low THD of AC currents which are in phase with the fundamental voltages of PMSG can be achieved by the proposed control technique.
[Show abstract][Hide abstract] ABSTRACT: In order to overcome the problems such as heavy distortion of winding current, low power factor and high cost of DC inductor met in the traditional rectified permanent magnet (PM) wind generation system, a circuit of cascaded single phase power factor correction (PFC) rectifier pair is proposed and discussed. In the new scheme, proper designed armature inductor of the generator is used as boost inductor, and the winding current is controlled by PWM to approach a sinusoidal waveform aligned with the back EMF in the winding. The DC ports of two such PFC rectifiers linked to a pair of windings placed perpendicularly are then connected in cascade that avoids the voltage ripple at DC link. Simulation and experiments have been performed to validate the new scheme.