Multi-port Power Electronic Interface Research Articles

Investigating and Analyzing the Impact of a Bidirectional Multiport Power Electronic Transformer Interface on the Power Quality and Stability of Interconnected Microgrids

Investigating and Analyzing the Impact of a Bidirectional Multiport Power Electronic Transformer Interface on the Power Quality and Stability of Interconnected Microgrids

Critical Reliability Improvement Using Q-Learning-Based Energy Management System for Microgrids

This paper presents a power distribution system that prioritizes the reliability of power to critical loads within a community. The proposed system utilizes reinforcement learning methods (Q-learning) to train multi-port power electronic interface (MPEI) systems within a community of microgrids. The primary contributions of this article are to present a system where Q-learning is successfully integrated with MPEI to reduce the impact of power contingencies on critical loads and to explore the effectiveness of the subsequent system. The feasibility of the proposed method has been proven through simulation and experiments. It has been demonstrated that the proposed method can effectively improve the reliability of the local power system—for a case study where 20% of the total loads are classified as critical loads, the system average interruption duration index (SAIDI) has been improved by 75% compared to traditional microgrids with no load schedule.

Control and management of hybrid AC/DC microgrid based on Γ‐Z‐source converter

This article studies a hybrid AC/DC microgrid with bidirectional Γ-Z-source inverter as an interlinking converter (IC). The Γ-Z-source inverter is capable of providing high-voltage gainand it does not have the drawbacks of the conventional inverters. In this hybrid microgrid, DC-type energy sources and loads are connected in DC sub-grid and AC-type energy sources and loads are connected in AC sub-grid to reduce the extra power conversion stages in both AC and DC sub-grids. Therefore system volume and cost decreases and system reliability and efficiency increases. In DC sub-grid, the advantages of multi-port power electronic interface (MPEI) are utilised. The individual DC–DC power converter, a MPEI, is used for interconnecting DC distributed generators. Photovoltaic system and battery unit are used as DC distributed generators. The article presents the control of three operation modes including grid-connected mode, islanded mode and islanded mode with power flow management and the IC and distributed generators. For power sharing management, droop strategy is used. The performance of the proposed IC in all three operation modes is evaluated by time domain simulations in MATLAB/Simulink.

Integration of Inductively Coupled Power Transfer and Hybrid Energy Storage System: A Multiport Power Electronics Interface for Battery-Powered Electric Vehicles

Detailed in this paper is a multiport power electronics interface which serves as an energy router for on-board electric and plug-in hybrid electric vehicles with inductively coupled power transfer (ICPT) and hybrid energy storage systems (HESS). The existing body of literature on HESSs lacks a unified controller and modular, flexible structure as well as integration of ICPT. In battery/ultracapacitor systems, this leads to piece-meal control of sources resulting in battery currents which are not fully decoupled from high-frequency/high-magnitude current and ultra-capacitor (UC) state of charge (SoC) not being properly controlled. A central controller is proposed in this paper which completely decouples the battery from both high-frequency and high-magnitude current, controls the SoC of the UCs, and models the SoC of the UCs in the stability analysis of the system. This system is particularly useful for online charging of HEVs in highway-type applications where ICPT pulse charging will be present. Solving the challenges of pulse charging will bring ICPT technology one step closer to widespread integration which has the potential to greatly reduce societies' dependence on fossil fuel. Simulation and experimental results verify the feasibility of the proposed techniques.

Dynamic Behavior of Multiport Power Electronic Interface Under Source/Load Disturbances

This paper presents the dynamic behavior of multiport power electronic interface (MPEI) under load/source disturbances. A cascaded topology for MPEI is considered. This system is capable of power management for local generations, loads, and storage systems. Large-signal and small-signal models for MPEI are developed. These models are combined with corresponding control algorithms. Simulated and experimental transient responses to disturbances on each port are presented. The behavior of MPEI in response to each disturbance is analyzed. Simulation and experimental results are compared in order to verify the model.

Multiport Power Electronic Interface—Concept, Modeling, and Design

The continuous effort to improve efficiency, reduce particle, and greenhouse gase emissions leads to the emergence of the concept “more electric.” This concept helps to boost the performance as well as the flexibility of the domestic and vehicular applications; however, on the other hand, it excessively burdens current power networks (including vehicle power systems). In order to remedy this problem, simultaneous usage of renewable sources and energy storages is encouraged. A multiconverter system is commonly adopted to process the renewable power in form of distributed generation. However, due to the discrete structure of such systems, power flow and load regulation are coordinated via communication channel, which inevitably reduces the reliability and dynamic response of the system. This paper presents the concept of multiport power electronic interface (MPEI) for renewable energy sources and storages. With a unified modular topology and highly integrated digital control system, controlled quasi-current source is achieved for each input port in both steady-state and transient power-sharing modes. MPEI analysis, modeling, design, and system operation are treated in a systematic manner in this paper. Both power stages and digital control system are implemented for a five-port MPEI. Experiments are conducted under meaningful operation scenarios. The results are presented to prove the feasibility of MPEI concept and system design methodology.