Improved Predictive Direct Power Control of Doubly Fed Induction Generator During Unbalanced Grid Voltage Based on Four Vectors

A new hybrid control scheme for minimizing torque and flux ripple for DFIG‐based WES under random change in wind speed

“…The objective of this paper is to propose a hybrid controller scheme by using both DTC and VC methods . The VC is applied to the GSC, to adjust DC‐link voltage across capacitor, d‐q currents and also enhance grid power quality.…”

“…The objective of this paper is to propose a hybrid controller scheme by using both DTC and VC methods. 19,20 The VC is applied to the GSC, to adjust DC-link voltage across capacitor, d-q currents and also enhance grid power quality. The DTC technique is applied to the RSC to regulate the electromagnetic torque and rotor flux magnitude and also indirectly control of both stator active and reactive powers.…”

Modulated Model Predictive Direct Power Control of DFIM Considering Magnetic Saturation Effects

“…The application of any MPC scheme requires prediction of state variables. For this, the rotor current state equation (6) and the active and reactive power state equations (13) and (14) are discretized using Euler's approximation as follows, where k denotes current sampling instant and k + 1 the next and T s is the sampling time. Even though the grid voltagev g , the stator fluxλ s and the slip frequency ω sl do not vary much over one sampling interval, they are written with sampling instant markers k, k − 1 for correctness.…”

“…Direct power control is usually achieved the same way [2] as direct torque and flux control of an induction machine, however this leads to a non-constant converter switching frequency. Model predictive control (MPC) in its canonical finite control set (FCS) implementation also results in a variable switching frequency [8], [9], however, some authors have reported the application of prediction-based control with constant switching frequency [4]- [6] that uses a modulator.…”

“…This scheme is combined with a rotor position sensorless control. Another direct power control technique with fixed switching frequency and under unbalanced grid conditions is investigated in [6]. Here the stator active and reactive power slopes are estimated based on different inverter switching voltage vectors and four vectors that have positive durations, and that minimize a cost function of power errors, are applied to achieve power control.…”