Three‐phase multi‐level converter equivalent circuit topology. SM, submodule

Three‐phase multi‐level converter equivalent circuit topology. SM, submodule

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Abstract In recent years, the modular multi‐level converter (MMC) has been widely used in high and medium voltage DC transmission systems because of its topological advantages. However, for an MMC with a two‐stage model predictive control (TSMPC) method, it is difficult to precisely and reasonably design the weighting factor in the cost function. H...

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... To solve the issue of slow dynamic response when using a PI current controller, in recent years, there has been an increasing number of researchers delving into predictive control methods and applying them to PFC converters [13][14][15][16]. A model predictive control (MPC) method in ref. [17] is applied, compared to the PI controller, MPC demonstrates superior performance and has garnered widespread attention. ...
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A novel predictive control method with conduction mode detection is proposed to suppress input current distortion of three‐level power factor correction (PFC) converters. In PFC converter, the input current is mostly distorted in continuous conduction mode (CCM) with conventional control methods. The proposed predictive control method comprises of a predictive CCM algorithm, a predictive discontinuous conduction mode (DCM) algorithm, and a conduction mode detection technique. By analysing four switching states of PFC converter and based on the inductor current ripple, predictive control duty cycles in CCM and DCM are derived, and the optimal duty cycle is determined by forecasting the next cycle current. According to the duty cycle characteristics, the conduction mode is detected without additional detection algorithms and circuits, achieving the input current tracking the input voltage. Finally, the effectiveness and correctness of the proposed predictive control method are validated through simulation and experiment.
... The International Thermonuclear Experimental Reactor (ITER) facility under construction aims to build a sustainable combustion Tokamak fusion experimental reactor to verify the technical feasibility of a nuclear fusion reactor [2]. The ITER Pulsed Power Network adopting similar topology has done a variety of research on the overall control scheme, cooperative control scheme and energy management mechanism of the system [7][8][9]. However, there is a lack of detailed research on the startup strategy of E-STATCOM. ...
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... In this highly complex converter, these strategies aim to fulfill several control objectives, namely HVAC bus current reference tracking, cell capacitor voltage balancing and minimization of circulating currents (between converter legs and the HVDC bus). Over recent years, several strategies based on FCS-MPC approach have been proposed for the MMC [76][77][78][79][80][81], and, more recently, CCS-MPC strategies have also been investigated [82][83][84][85][86][87][88][89][90] for this converter. ...
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Due to its high functionality, the solid state transformer (SST) represents an emerging technology with huge potential to replace the conventional low-frequency transformer (LFT) in a wide range of applications, including railway traction, smart grids, and others. On the other hand, model predictive control (MPC) has proven to be a highly promising control approach for several power electronics systems, especially those based on multiple power converters. Considering these facts, over recent years, different MPC techniques have been proposed for different types of SSTs. In addition to that, numerous MPC strategies have also been investigated for various power converters topologies that can be used in SSTs. However, a paper summarizing and discussing MPC strategies in the framework of SSTs has not yet been proposed in the literature, being the main goal of this work. In this paper, all the existing MPC techniques in complete SST topologies will be presented and discussed. In addition, for the sake of the example, an overview of MPC strategies in converter topologies typically used in SSTs will also be presented.
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