Control of Pmsg Wecs with Back‐to‐Back Connected Converters

This chapter discusses the predictive control of full‐scale low‐voltage (LV) and medium voltage (MV) voltage source converters (VSCs) employed in permanent magnet synchronous generator (PMSG) wind energy conversion systems (WECS). The variable voltage and frequency output of PMSG is first rectified to DC by using the generator‐side 2L‐VSR. An imbalance between DC‐link capacitors voltage is undesirable because it can cause high stress and damage to semiconductor devices. Digital control systems play an important role in the power conversion of WECS. They enable the safe, reliable, and efficient operation of power converters to ensure maximum energy capture and compatibility to the grid integration requirements. After initializing the digital controller and calculating the reference generator and grid currents, the PCC algorithm enters an iterative loop where the generator and grid currents are predicted and cost function minimization is performed. The control objectives of PMSG WECS can be achieved by regulating the stator currents, torque and flux, active and reactive powers, and rotor speed.