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iEnergy 2022, 1(3): 279-284 https://doi.org/10.23919/IEN.2022.0042
Letter | Open Access | Issue | Published: 20 September 2022

Equilibrium mechanism between dc voltage and ac frequency for ac–dc interlinking converters

Show Author's Information Haixu Shi1,2,  Kai Sun2( ),  Xiaochao Hou2,  Yunwei Li3,  Haihao Jiang1
Guangdong Midea Refrigeration Equipment Co., Ltd., Guangdong, Foshan 528311, China
Department of Electrical Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing 100084, China
Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
Keywords:
Virtual machine, microgrid, interlinking converter, unified control
Cite this article:
Shi H, Sun K, Hou X, et al. Equilibrium mechanism between dc voltage and ac frequency for ac–dc interlinking converters. iEnergy, 2022, 1(3): 279-284. https://doi.org/10.23919/IEN.2022.0042
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Abstract Full text About this article

The equilibrium between dc bus voltage and ac bus frequency (Udc-f equilibrium) is the algorithm core of unified control strategies for ac-dc interlinking converters (ILCs), because the equilibrium implements certain mechanism. However, what the mechanism is has not been explicitly explored, which hinders further studies on unified control. This paper reveals that the state-space model of a Udc-f equilibrium controlled ILC is highly similar to that of a shaft-to-shaft machines system. Hence a detailed mechanism is discovered and named “virtual shaft-to-shaft machine (VSSM)” mechanism. A significant feature of VSSM mechanism is self-synchronization without current sampling or ac voltage sampling.


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About this article

Equilibrium mechanism between dc voltage and ac frequency for ac–dc interlinking converters

Show Author's information Haixu Shi1,2, Kai Sun2( ), Xiaochao Hou2, Yunwei Li3, Haihao Jiang1
Guangdong Midea Refrigeration Equipment Co., Ltd., Guangdong, Foshan 528311, China
Department of Electrical Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing 100084, China
Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada

Abstract

The equilibrium between dc bus voltage and ac bus frequency (Udc-f equilibrium) is the algorithm core of unified control strategies for ac-dc interlinking converters (ILCs), because the equilibrium implements certain mechanism. However, what the mechanism is has not been explicitly explored, which hinders further studies on unified control. This paper reveals that the state-space model of a Udc-f equilibrium controlled ILC is highly similar to that of a shaft-to-shaft machines system. Hence a detailed mechanism is discovered and named “virtual shaft-to-shaft machine (VSSM)” mechanism. A significant feature of VSSM mechanism is self-synchronization without current sampling or ac voltage sampling.

Keywords: Virtual machine, microgrid, interlinking converter, unified control

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Received: 16 September 2022
Accepted: 02 October 2022
Published: 20 September 2022
Issue date: September 2022

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Copyright: by the author(s). The articles published in this open access journal are distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/).

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