Mengxuan Shi¹, Lintao Li², Dejun Shao¹, Xiaojie Pan¹, Xingyu Shi^2,*, Yuxun Wang²

Energy Engineering, Vol.123, No.1, 2026, DOI:10.32604/ee.2025.069915 - 27 December 2025

Abstract In wind power transmission via modular multilevel converter based high voltage direct current (MMC-HVDC) systems, under traditional control strategies, MMC-HVDC cannot provide inertia support to the receiving-end grid (REG) during disturbances. Moreover, due to the frequency decoupling between the two ends of the MMC-HVDC, the sending-end wind farm (SEWF) cannot obtain the frequency variation information of the REG to provide inertia response. Therefore, this paper proposes a novel coordinated source-network-storage inertia control strategy based on wind power transmission via MMC-HVDC system. First, the grid-side MMC station (GS-MMC) maps the frequency variations of the REG to… More >

Yechun Xin¹, Xinyuan Zhao¹, Dong Ding², Shuyu Chen², Chuanjie Wang², Tuo Wang^1,*

Energy Engineering, Vol.123, No.1, 2026, DOI:10.32604/ee.2025.069748 - 27 December 2025

Abstract To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current (HVDC) links and multi-infeed DC systems in load-center regions, this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter (MMC-CLCC) HVDC transmission system and its corresponding control strategy. First, the system topology is constructed, and a submodule configuration method for the MMC—combining full-bridge submodules (FBSMs) and half-bridge submodules (HBSMs)—is proposed to enable direct power flow reversal. Second, a hierarchical control strategy is introduced, including MMC voltage control, CLCC current control, and a coordination mechanism, along with the derivation of… More >

Hui Fang¹, Jingsen Zhou¹, Haozheng Wang^2,*, Yanxu Wang², Hongji Xiang¹, Yechun Xin²

Energy Engineering, Vol.120, No.4, pp. 831-850, 2023, DOI:10.32604/ee.2023.025171 - 13 February 2023

Abstract Recently, high-frequency oscillation of the modular multilevel converter (MMC) based high-voltage direct current (HVDC) projects has attracted great attentions. In order to analyze the small-signal stability, this paper uses the harmonic state-space (HSS) method to establish a detailed frequency domain impedance model of the AC-side of the HVDC transmission system, which considers the internal dynamic characteristics. In addition, the suggested model is also used to assess the system's high-frequency oscillation mechanism, and the effects of the MMC current inner loop control, feedforward voltage links, and control delay on the high-frequency impedance characteristics and the effect More >

Mingwan Mei¹, Ping Wang¹, Yanbo Che^1,*, Zihan Lv¹, Zmarrak Wali Khanand¹, Chao Xing^1,2

Energy Engineering, Vol.119, No.2, pp. 591-607, 2022, DOI:10.32604/ee.2022.016585 - 24 January 2022

Abstract

In the medium voltage direct current (MVDC) transmission system, a small number of MMC sub modules will reduce the power quality. In this paper, based on the research background of Photovoltaic Medium Voltage Direct Current (PV-MVDC) system, a Hybrid Modulation Strategy based on the Decoupled Double Synchronous Reference Frame (DDSRF) control strategy is proposed. The dual arm complementary hybrid modulation combining nearest-level-SPWM (NL-SPWM) can keep the number of SMs in the ON state constant. Then, the corresponding voltage sharing control algorithm of sub module (SM) is introduced. Through theoretical calculation, the modulation strategy can be found

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