A new three-phase active rectifier topology is proposed for bipolar dc distribution, which can achieve the independent dc-pole control, with only one two-level voltage source converter and an ac-side grounding inductor. The averaged large-signal model and linearized small-signal model of the rectifier are derived in the stationary reference frame. Moreover, a control system is proposed with proper controller parameters. Besides, the rectifier is tested on an experiment platform. Comprehensive experiment results are given and analyzed to validate the function of the proposed rectifier under different operation conditions, including the rectifier start-up performance, rectifier dynamics with unbalanced dc loads for two poles, and rectifier dynamics with asymmetrical dc voltages for two poles. Finally, the proposed rectifier is compared with other two existing ac-dc conversion approaches, in terms of required number and rating of components as well as power losses with different load imbalance levels, which further highlight some potential benefits of the proposed topology.

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The Modular Multilevel Converter (MMC) is the state-of-the-art topology for Voltage Source Converter HVDC (VSC-HVDC). Despite its advantages, this converter handles large internal low-frequency energy ripples and the capacitance that supports these dynamics is a key design parameter that affects the operating region of the converter. Different strategies can be found in literature to increase the feasible region of operation of the converter. Nevertheless, they are typically openloop in nature and use pre-calculated control references. This paper presents an alternative based on Model Predictive Control (MPC) that steers the system through optimal control trajectories that are calculated online. This provides feedback and corrective control action in real time. The predictive controller used for this purpose is presented and a Linear Time-Varying (LTV) approximation is used to reduce the computational burden of the algorithm. The feasible boundaries of the converter are sought and the final performance of the control algorithm is evaluated through detailed simulations using a switching model of the converter.

This paper proposes an innovative distribution network structure and functionality, based on the intelligent power router concept. The intelligent power router is a device that controls the power flow by the means of power converters. The operation of such a system is analyzed. Moreover this concept is validated through simulation and experimental validation.

This paper describes a model predictive strategy to reduce the sub-module voltage oscillation in a single-phase modular multilevel converter. This task is accomplished by a predictive controller which solves an optimal control problem sequentially. By choosing the objective function weights appropriately, this controller can naturally trade-off sub-modules voltage ripple and recirculating current. It is shown that the sub-module voltage oscillation can be reduced without degrading the efficiency excessively, enhancing the performance of the overall converter. Additionally, it is guaranteed that the recirculating current can be regulated without exceeding the physical limitations of the device.