In this paper, a voltage modulated direct power control for three-phase pulsewidth modulated rectifier is proposed. With the suggested method, the differential equations describing the rectifier dynamics are changing from a linear time-varying system into a linear time-invariant one. In this way, conventional feedback and feedforward controllers are applicable for the independent control of active and reactive powers. The proposed method has guaranteed that the closed system is globally exponentially stable. A feedback linearization method is also employed for generating the active power reference of inner loops. Finally, some experimental tests are conducted to verify its effectiveness.
9 February 2021 in IEEE Transactions on Industrial Electronics
For several reasons, particularly due to the mismatch in the feeder impedance, accurate power sharing in islanded microgrids is a challenging task. To get around this problem, a distributed event-triggered power sharing control strategy is proposed in this article. The suggested technique adaptively regulates the virtual impedances at both fundamental positive/negative sequence and harmonic frequencies and, therefore, accurately share the reactive, unbalanced, and harmonics powers among distributed generation units. The proposed method requires no information of feeder impedance and involves exchanging information among units at only event-triggered times, which reduces the communication burden without affecting the system performance. The stability and interevent interval are analyzed in this article. Finally, experimental results are presented to validate the effectiveness of the proposed scheme.
4 June 2020 in IEEE Transactions on Industrial Electronics
This article presents a reduced-order generalized proportional-integral observer based resonant super-twisting sliding mode controller (RST-SMC) for the three-phase ac-dc converters. On the contrary to utilizing the proportional-integral controller in regulating the dc-link voltage, which may cause large undershoot/overshoot under the disturbance, the proposed voltage control strategy for the dc-link has high disturbance rejection ability and the settling time has been greatly reduced. In addition, the proposed RST-SMC in the current control loop not only preserve the merits of the sliding mode controller but also achieve the current tracking without steady-state error in the stationary α- β frame. The effectiveness of the proposed method has been verified by a lab-constructed experimental prototype.
12 July 2017 in IEEE Transactions on Power Electronics
To regulate the dc-link voltage of three-phase ac/dc converters, an enhanced state observer-based controller is presented in this letter. The proposed controller, contrary to the traditional ones, does not require the dc-link current measurement and offers a “plug and play” capability, a rather high disturbance rejection ability and robustness against the dc-link capacitance parameter variation. The design procedure of the suggested controller is discussed, and its effectiveness is verified using experimental results.
27 October 2021 in IEEE Transactions on Sustainable Energy
Due to the droop control applied in islanded DC microgrids, DC bus voltage recovery, and current sharing cannot be guaranteed simultaneously. To solve this problem, a distributed dynamic event-triggered control method is proposed in this paper. The presented control scheme can remove DC bus voltage deviation while achieving the current sharing among distributed generation (DG) units. In addition, the proposed method requires no global information, and only the DC bus voltage from the physical network is needed. Moreover, the data of neighboring DGs at only event-triggered times are involved, which greatly reduces the communication burden of the DC microgrid communication network. The stability of the proposed method is demonstrated through the Lyapunov function, and Zeno behavior can be excluded as well. Finally, the experimental results with four case studies are presented to validate the effectiveness of the proposed method.