Results 31 to 40 of about 77,102 (304)
Protection and Control of Modern Power Systems, 2023 In the presence of an MMC-HVDC system, current differential protection (CDP) has the risk of failure in operation under an internal fault. In addition, CDP may also incur security issues in the presence of current transformer (CT) saturation and outliers.
Yingyu Liang +3 more
semanticscholar +1 more source
Enhanced flat-topped modulation for MMC control in HVDC transmission systems [PDF]
, 2017 Flat-topped modulation is a member of the family of triplen-series injection techniques that have been extensively utilized in PWM inverter systems to increase the DC-link, and hence semiconductor, utilization.
Fletcher, John E. +3 more
core +1 more source
Enhanced AC voltage and frequency control on offshore MMC station for wind farm [PDF]
, 2017 For HVDC transmission systems based on modular multilevel converter (MMC) for connecting large offshore wind farms, the offshore AC voltage is regulated by the offshore MMC station and stable offshore AC voltage and frequency are important for the stable
Jing, Yiran, Li, Rui, Wang, Yi, Xu, Lie
core +1 more source
Studies of commutation failures in hybrid LCC/MMC HVDC systems [PDF]
Global Energy Interconnection, 2020 A hybrid of line commutated converters(LCCs) and modular multi-level converters(MMCs) can provide the advantages of both the technologies. However, the commutation failure still exists if the LCC operates as an inverter in a hybrid LCC/MMC system. In this paper, the system behavior during a commutation failure is investigated.
Gen Li +6 more
openaire +2 more sources
Frontiers in Energy Research, 2021 The hybrid HVDC with cascaded multi-infeed MMC inverters is proposed in recent years and it will be put into reality in near future. But the control characteristic of this hybrid HVDC have not been discussed in details.
Jingbo Zhao, Yan Tao
doaj +1 more source
Generalized Voltage-based State-Space Modelling of Modular Multilevel Converters with Constant Equilibrium in Steady-State [PDF]
, 2017 This paper demonstrates that the sum and difference of the upper and lower arm voltages are suitable variables for deriving a generalized state-space model of an MMC which settles at a constant equilibrium in steady-state operation, while including the ...
Bergna-Diaz, Gilbert +4 more
core +3 more sources
Energies, 2019 This paper determines the minimum short circuit ratio (SCR) requirement for a modular multilevel converter based high-voltage direct current (MMC-HVDC) transmission systems.
Zheren Zhang +4 more
doaj +1 more source
Stability Comparison Between Grid-forming and Grid-following Based Wind Farms Integrated MMC-HVDC
Journal of Modern Power Systems and Clean Energy, 2023 Grid-forming (GFM) control based high-voltage DC (HVDC) systems and renewable energy sources (RESs) provide support for enhancing the stability of power systems. However, the interaction and coordination of frequency support between the GFM-based modular
Rongcai Pan +5 more
doaj +1 more source
Zhongguo dianli, 2022 In MMC impedance modelling, the existing research does not take into account the influence of the capacitive voltage transformer (CVT) measurement characteristics on the mid and high frequency bands of the MMC impedance, which may reduce the accuracy of ...
Qinan LI +8 more
doaj +1 more source
The efficacy of recycled concrete aggregate for removal phosphorus in synthetic wastewater with different pH value [PDF]
, 2020 Phosphorus (P) is the main nutrient element for plant growth in the natural water system. However, unnecessary phosphorus loads in water bodies from industrial, agricultural and household wastes may cause the overgrowth of aquatic plants or algae which ...
Abd Roni, Norwardatun +3 more
core +2 more sources