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This paper presents a novel fault ride-through (FRT) capability with the use of active converters (Vienna rectifier-I and five-level three-phase modular multilevel converter (MMC)) integrated with permanent magnet synchronous generator (PMSG) supplying AC load. The DC-link fault is controlled with the use of fault blocking diode and MMC sub-module (SM) based wind power plant (WPP). A 16 kW, 60 Hz, PMSG and wind turbine (WT) integrated with the machine-side converter (MSC), and grid-side converter (GSC) are utilized as wind farm components, along with direct current (DC) transmission grid. This topology contributes to the stability and reliability of the system by ensuring continuous output power under transient fault conditions. The functional response of the system is presented using power simulator (The PowerSim, Rockville, USA) software to demonstrate the performance of the proposed controller. [ABSTRACT FROM AUTHOR]

The paper deals with the accomplishment of a FPGA-based dynamic model of a three-phase Vienna rectifier controlled in order to feature unity power factor operations. Such a model has been developed for the Hardware In the Loop (HIL) implementation of a test rig in which the power converter is replaced with an embedded system using a FPGA board. The proposed approach has been fostered mainly to test different converter control algorithms in a fast and safe way. Such solution is based on a software platform environment with a high-level abstraction that ensures a good trade-off between accuracy and hardware resources, also allowing a fast prototyping procedure. The results obtained by the HIL implementation have been compared with those of a fully hardware experimental rig, confirming a very good agreement in terms of accuracy and dynamic behavior. [ABSTRACT FROM AUTHOR]

This paper proposes the predictive control with the discrete space-vector modulation (DSVM) for Vienna rectifier connecting to the permanent magnet synchronous generator (PMSG) of the wind turbine system (WTS). Since Vienna rectifier has the special operation principle, Vienna rectifier generates only the feasible eight voltage vectors, which can be a candidate vector for the predictive control, depending on the sign of the input currents. In the proposed predictive control, the feasible voltage vectors are extended from 8 to 19 consisting the 8 original voltage vectors and 11 virtual voltage vectors by using the DSVM for improving the current quality related to the torque ripple, vibration, and noise, and the neutral-point voltage balance with low voltage ripple is guaranteed by using the offset value calculated based on the model of two dc-link capacitors in Vienna rectifier. The scheme for reducing calculation burden is applied in selecting the candidate vector. In addition, the limited operation range for the maximum torque per ampere control of PMSG connected to Vienna rectifier is analyzed. The performance of the proposed predictive control with DSVM for Vienna rectifier with PMSGs is verified in simulation and experiment. [ABSTRACT FROM AUTHOR]

This paper proposes a generalized design framework for three-phase Vienna rectifiers to handle the neutral point voltage balance issue. On the basis of the design framework, it is convenient to construct various neutral point voltage balancing methods with the guarantee of stability. As demonstration, three representative neutral point voltage balance approaches are presented by choosing different zero-sequence voltages. A comprehensive comparison among the three approaches is given in the aspects of input current quality, capacitor voltage fluctuation, and system efficiency. The comparison results provide guidance for constructing the most appropriate approach based on the specific requirement. Finally, simulation and experimental results verify the correctness and effectiveness of the presented approaches and the related performance analysis. [ABSTRACT FROM AUTHOR]

The VIENNA rectifier is increasingly being considered as the active front-end converter in many applications that do not require regeneration or controllable input reactive power. In such applications, this rectifier is normally operated at unity source displacement factor, which derates its nominal voltampere (VA) rating. Moreover, in the “source voltage oriented” reference frame that is normally used for control, this rectifier has complex operating limits on the rectifier terminal voltage (imposed by the operating conditions), which needs to be computed online to avoid the line currents from going through zero-crossing distortions. Also, the source voltage has to be either measured or estimated, which further increases the cost and/or computational burden. This paper proposes a control method that eliminates the requirement of the input voltage sensors (or estimators) and makes the limits on the rectifier terminal voltage far simpler to compute. The control method is implemented in the input line current oriented reference frame, considering unity displacement factor at the rectifier input terminals, which minimizes the VA rating of the rectifier (for a given rated load power). The proposed sensorless current-oriented control approach is compared with the conventional voltage-oriented control strategy through experimental results. [ABSTRACT FROM AUTHOR]

This paper studies the inherent relationship between currents and zero-sequence components. Then a precise algorithm is proposed to calculate the injected zero-sequence component to control the DC-Link neutral-point voltage balance, which can result in a more efficient and flexible neutral point voltage balance with a desirable performance. In addition, it is shown that carriedbased PWM with the calculated zero-sequence component scheme can be equivalent to space-vector pulse-width modulation (SVPWM). Based on the proposed method, the optimal zero-sequence component of the feasible modulation indices is analyzed. In addition, the unbalanced load limitation of the DC-Link neutral-point voltage balance control is also revealed. Simulation and experimental results are shown to verify the validity and practicality of the proposed algorithm. [ABSTRACT FROM AUTHOR]